US20010015887A1 - Electronic control unit having connector positioned between two circuit substrates - Google Patents
Electronic control unit having connector positioned between two circuit substrates Download PDFInfo
- Publication number
- US20010015887A1 US20010015887A1 US09/739,961 US73996100A US2001015887A1 US 20010015887 A1 US20010015887 A1 US 20010015887A1 US 73996100 A US73996100 A US 73996100A US 2001015887 A1 US2001015887 A1 US 2001015887A1
- Authority
- US
- United States
- Prior art keywords
- circuit substrate
- control unit
- connector
- electronic control
- sheet
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 239000000758 substrate Substances 0.000 title claims abstract description 174
- 238000000034 method Methods 0.000 claims description 10
- 238000004519 manufacturing process Methods 0.000 claims description 6
- 230000017525 heat dissipation Effects 0.000 claims description 5
- 229910052751 metal Inorganic materials 0.000 abstract description 3
- 239000002184 metal Substances 0.000 abstract description 3
- 238000005476 soldering Methods 0.000 description 12
- 239000011347 resin Substances 0.000 description 4
- 229920005989 resin Polymers 0.000 description 4
- 230000008901 benefit Effects 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 229910000679 solder Inorganic materials 0.000 description 3
- 239000004593 Epoxy Substances 0.000 description 1
- 239000000853 adhesive Substances 0.000 description 1
- 230000001070 adhesive effect Effects 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 239000004744 fabric Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 239000007769 metal material Substances 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K7/00—Constructional details common to different types of electric apparatus
- H05K7/20—Modifications to facilitate cooling, ventilating, or heating
- H05K7/20845—Modifications to facilitate cooling, ventilating, or heating for automotive electronic casings
- H05K7/20854—Heat transfer by conduction from internal heat source to heat radiating structure
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K1/00—Printed circuits
- H05K1/02—Details
- H05K1/14—Structural association of two or more printed circuits
- H05K1/144—Stacked arrangements of planar printed circuit boards
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K5/00—Casings, cabinets or drawers for electric apparatus
- H05K5/0026—Casings, cabinets or drawers for electric apparatus provided with connectors and printed circuit boards [PCB], e.g. automotive electronic control units
- H05K5/0082—Casings, cabinets or drawers for electric apparatus provided with connectors and printed circuit boards [PCB], e.g. automotive electronic control units specially adapted for transmission control units, e.g. gearbox controllers
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K7/00—Constructional details common to different types of electric apparatus
- H05K7/20—Modifications to facilitate cooling, ventilating, or heating
- H05K7/2089—Modifications to facilitate cooling, ventilating, or heating for power electronics, e.g. for inverters for controlling motor
- H05K7/209—Heat transfer by conduction from internal heat source to heat radiating structure
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T29/00—Metal working
- Y10T29/49—Method of mechanical manufacture
- Y10T29/49002—Electrical device making
- Y10T29/49117—Conductor or circuit manufacturing
- Y10T29/49124—On flat or curved insulated base, e.g., printed circuit, etc.
- Y10T29/4913—Assembling to base an electrical component, e.g., capacitor, etc.
Definitions
- the present invention relates to an electronic control unit for controlling operation of actuators and to a method of manufacturing the same.
- Electronic control units for use in various controls such as automotive engine control and transmission control, are generally known.
- the electronic control unit controls operation of actuators such as electromagnetic solenoids by supplying power thereto based on signals fed to and processed in the electronic control unit.
- Recent electronic controls for an automotive vehicle are becoming more sophisticated and multi-functional.
- Electric power to be controlled by driving elements in the electronic control unit is also becoming high.
- An amount of heat generated in the driving elements such as power transistors or power ICs contained in the electronic control unit becomes high. Such heat is transferred to control elements such as microcomputers contained in the same electronic control unit.
- FIG. 1 An example of conventional electronic control units is shown in FIG. 1.
- a circuit substrate 40 on which a driving element 5 and a control element 3 are mounted is contained in a casing 7 .
- a connector 2 for electrically connecting the electronic control unit to outside sensors and actuators is also mounted in the casing.
- Heat generated in the driving element 5 such as a power transistor is transferred to the control element 3 such as a microcomputer, thereby heating the control element 3 . If the control element 3 is excessively heated, its operation stability cannot be maintained. It could be possible to enlarge the circuit substrate 40 to suppress the heat transfer from the driving element 5 to the control element 3 . However, it is not preferable, or may not be possible, to enlarge the size of the electronic control unit from viewpoints of a mounting space and a cost of the electronic control unit.
- the present invention has been made in view of the above-mentioned problem, and an object of the present invention is to provide an improved electronic control unit, in which the heat transfer from the driving elements to the control elements is suppressed without enlarging the size of the electronic control unit.
- the electronic control unit is composed of a metal casing, a driving circuit substrate, a control circuit substrate, a flexible printed-circuit sheet connecting both substrates, and a connector for connecting the electronic control unit to outside actuators and sensors.
- the control circuit substrate includes control elements such as a microcomputer for processing signals fed from the outside sensors and for supplying control signals to the driving circuit substrate.
- the driving circuit substrate includes driving elements such as power transistors for supplying electric power to the outside actuators based on the control signals fed from the control circuit substrate.
- the metal casing has a heat dissipation plate on which the driving circuit substrate generating a large amount of heat is mounted.
- the control circuit substrate that generates substantially no heat is contained in the casing apart from the driving circuit substrate.
- a separating space for suppressing heat transfer from the driving circuit substrate to the control circuit substrate is formed between both substrates.
- the connector is positioned in the separating space.
- the separating space in the casing is also utilized as a space for containing the connector.
- Both substrates are electrically connected by a flexible printed-circuit-sheet which absorbs vibration energy to protect electrical connections.
- the flexible printed-circuit-sheet is connected to the control circuit substrate at a vicinity of connector pins connecting the connector to the control circuit substrate to reduce electrical resistance in the circuit.
- the connector may be mounted on the control circuit substrate and electrically connected thereto.
- both substrates are first connected by the flexible printed-circuit-sheet, and then the connector is mounted on the control circuit substrate to simplify the manufacturing process.
- the connector may be mounted on the casing and electrically connected to the flexible printed-circuit-sheet.
- the connector is electrically connected to the flexible printed-circuit-sheet, and then the flexible sheet is electrically connected to both substrates. After that, the connector is mounted on the casing.
- Elements for absorbing noise coming into the electronic control unit may be surface-mounted on the flexible sheet.
- Components having inserting leads may also be mounted on the flexible sheet, removing such components from the control circuit board. If no such component is mounted on the control circuit substrate, electrical connections on the control circuit substrate can be carried out only by reflow-soldering.
- a portion of the flexible sheet on which electric components are mounted may be made of a hard printed-board to secure stable electrical connections against vibration.
- Components mounted on the flexible sheet may be supported by a holder formed integrally with the connector to secure a higher mechanical strength.
- the driving circuit substrate and the control circuit substrate are positioned in the casing with a separating space therebetween, and the connector is disposed within the separating space.
- the separating space for suppressing the heat transfer is also utilized as a space for containing the connector therein. Accordingly, the heat transfer is effectively suppressed without enlarging the size of the electronic control unit.
- FIG. 1 is a cross-sectional view showing a conventional electronic control unit
- FIG. 2A is a cross-sectional view showing an electronic control unit as a comparative example to embodiments of the present invention
- FIG. 2B is a plan view of the electronic control unit shown in FIG. 2A with its upper case removed;
- FIG. 3A is a cross-sectional view showing an electronic control unit as a first embodiment of the present invention
- FIG. 3B is a cross-sectional view showing one stage of assembling the electronic control unit shown in FIG. 3A;
- FIG. 3C is a perspective view showing the same assembling stage as shown in FIG. 3B;
- FIG. 4A is a cross-sectional view showing one stage of assembling an electronic control unit as a second embodiment of the present invention.
- FIG. 4B is a cross-sectional view showing the next assembling stage following the stage shown in FIG. 4A;
- FIG. 4C is a perspective view showing the same assembling stage as shown in FIG. 4A;
- FIG. 5A is a cross-sectional view showing an electronic control unit as a third embodiment of the present invention.
- FIG. 5B is a cross-sectional view showing one stage of assembling the electronic control unit shown in FIG. 5A;
- FIG. 5C is a cross-sectional view showing the next assembling stage following the stage shown in FIG. 5B;
- FIG. 5D is a perspective view showing the same assembling stage as shown in FIG. 5B;
- FIG. 6A is a cross-sectional view showing an electronic control unit as a fourth embodiment of the present invention.
- FIG. 6B is a cross-sectional view showing the electronic control unit shown in FIG. 6A, viewed from a connector side;
- FIG. 6C is a cross-sectional view showing one stage of assembling the electronic control unit shown in FIG. 6A;
- FIG. 6D is a cross-sectional view showing the next assembling stage following the stage shown in FIG. 6C;
- FIG. 7A is a cross-sectional view showing an electronic control unit as a fifth embodiment of the present invention.
- FIG. 7B is a cross-sectional view showing the electronic control unit shown in FIG. 7A, viewed from a connector side;
- FIG. 8A is a cross-sectional view showing an electronic control unit as a sixth embodiment of the present invention.
- FIG. 8B is a cross-sectional view showing the electronic control unit shown in FIG. 8A, viewed from a connector side;
- FIG. 9A is a cross-sectional view showing an electronic control unit as a seventh embodiment of the present invention.
- FIG. 9B is a cross-sectional view showing the electronic control unit shown in FIG. 9A, viewed from a connector side;
- FIG. 10 is a cross-sectional view showing an example of modified forms of the embodiments shown above.
- One solution for suppressing heat transfer from driving elements to control elements contained in the same casing is to divide the circuit substrate 40 shown in FIG. 1 into a substrate carrying only the control elements thereon and another substrate carrying the driving elements thereon.
- FIGS. 2A and 2B One example of such arrangements is shown in FIGS. 2A and 2B.
- FIG. 2A is a cross-sectional view and FIG. 2B is a plan view with an upper case removed.
- a control circuit substrate 10 carrying the control element 3 is supported in the middle portion of the casing 7 , while a driving circuit substrate 20 carrying the driving elements 5 is mounted on bottom heat dissipation plate of the casing 7 . Both substrates are electrically connected by a flexible printed-circuit-sheet 4 .
- a connector 2 for electrically connecting the electronic control unit to outside sensors and actuators is mounted on and electrically connected to the control circuit substrate 10 .
- the driving circuit substrate 20 is positioned apart from the control circuit substrate 10 with a certain space therebetween, the heat transfer from the substrate 20 to the substrate 10 can be suppressed. If it is possible to make the space between two substrates 10 , 20 sufficiently large, the heat transfer would be sufficiently suppressed. However, it is desirable to make this space smaller to make an entire control unit size smaller. The height of the upper half space in the casing 7 cannot be shortened because there is positioned the connector 2 .
- FIG. 3A A first embodiment of the present invention shown in FIG. 3A is designed to further improve the example shown in FIGS. 2A and 2B. The first embodiment of the present invention will be described in detail with reference to FIGS. 3 A- 3 C.
- the electronic control unit 1 is used for controlling operation of various actuators of an automotive engine 100 , such as ignition plugs and electromagnetic solenoids.
- the electronic control unit 1 is electrically connected to the actuators and sensors through a cable 102 .
- the electronic control unit 1 is composed of a casing 7 , a control circuit substrate 10 carrying control elements 3 thereon, a driving circuit substrate 20 carrying driving elements 5 thereon, and a connector 2 coupled to the cable 102 . Both substrates 10 and 20 are electrically connected through a flexible printed-circuit-sheet 4 .
- the casing 7 is composed of an upper case 7 a and a lower case 7 b , and both cases 7 a , 7 b are connected by screws 8 .
- the control circuit substrate 10 is mounted in the casing 7 , being inserted between the upper case 7 a and the lower case 7 b .
- the driving circuit substrate 20 is mounted on an inner wall 7 d of an upper wall 7 c of the casing 7 .
- the connector 2 is inserted through a side opening 7 e of the upper case 7 a so that its portion 2 a is positioned inside the casing 7 , and is mounted on the substrate 10 .
- the connector 2 is positioned in a space between a surface A (the inner surface 7 d of the upper wall 7 c ) and a surface B (the upper surface of the substrate 10 ), preferably in the space between a surface C (the lower surface of the substrate 20 ) and the surface B.
- a plurality of connector pins 6 extending from the connector 2 are inserted into the control circuit substrate 10 and electrically connected thereto.
- the control elements 3 consist of an one-chip microcomputer to which signals from various sensors are fed. The signals fed to the microcomputer are processed to form control signals to be supplied to the driving elements 5 .
- the control elements 3 also perform communication with various electronic components mounted on the automobile through the cable 102 .
- the control circuit substrate 10 on which the control elements 3 are mounted is made of a resin board such as an epoxy-impregnated glass-cloth, and control circuits are formed thereon. Electronic components (not shown) other than the control elements 3 are also mounted on both sides of the control circuit substrate 10 .
- the connector 2 is mounted on the control circuit substrate 10 , and the connector pins 6 are electrically connected to the control circuit substrate 10 .
- the connector pins 6 are connected to the control circuit substrate 10 at its left side end, and one end of the flexible printed-circuit sheet 4 is electrically connected to the control circuit substrate 10 by soldering at a vicinity of the position where the connector pins 6 are connected.
- the other end of the flexible printed-circuit sheet 4 is electrically connected to the driving circuit substrate 20 .
- the flexible printed-circuit sheet 4 is bent and connected to both substrates 10 , 20 with a proper allowance as shown in FIG. 3A, so that it absorbs vibration transferred from the engine and does not contacts the upper wall 7 c.
- the driving elements 5 mounted on the driving circuit substrate 20 are so-called switching elements for supplying electric power to the outside actuators.
- the electric power is supplied from an on-board battery (not shown) through the driving elements based on the control signals fed from the control elements 3 .
- the driving circuit substrate 20 is made of a heat-conductive ceramic plate on which driving circuits are formed. Components (not shown) other than the driving elements 5 are also mounted on the driving circuit substrate 20 .
- the driving circuit substrate is mounted on the inner surface 7 d of the upper wall 7 c in close contact therewith, so that heat generated in the driving elements 5 is easily transferred to the casing 7 and dissipated therefrom.
- the casing 7 is made of a metallic material such as cast aluminum, and its upper wall 7 c serves as a heat-dissipation plate.
- the driving elements 5 and other components are mounted on and connected to the driving circuit substrate 20 .
- the driving circuit substrate 20 is bonded on the inner surface 7 d of the upper wall 7 c with a heat-conductive adhesive which is cured by applying heat (e.g., 150° C.) for a certain time (e.g., 30 minutes). Heat resistance between the upper wall 7 c and the driving circuit substrate 20 is made as small as possible.
- the control elements 3 and other components are mounted on and connected to the control circuit substrate 10 .
- the connector 2 is also mounted on and connected to the control circuit substrate 10 .
- the upper case 7 a carrying the driving circuit substrate 20 thereon and the control substrate 10 are positioned as shown in FIG. 3B.
- the flexible printed-circuit-sheet 4 is placed over the both substrates 10 , 20 through the side opening 7 e of the upper case 7 a . Both ends of the flexible printed-circuit-sheet 4 are pressed down on the terminal portions of both circuit substrates 10 , 20 by jigs S.
- the flexible printed-circuit-sheets 4 is soldered to both substrates 10 , 20 , at their terminal portions under heat and pressure.
- solder is attached to the terminal portions of both substrates 10 , 20 , and then both ends of the flexible printed-circuit-sheet 4 are pressed down on the solder by heated jigs S. Since the connector 2 mounted on the control circuit substrate 10 prevents the flexible printed-circuit-sheet 4 from being extended flat, the upper case 7 a and the control circuit substrate 10 are positioned as shown in FIGS. 3B and 3C (FIG. 3C is a perspective view of FIG. 3B).
- the upper case 7 a is flipped over the control circuit substrate 10 so that the inner surface 7 d of the upper case 7 a faces the control circuit substrate 10 . Then, the control circuit substrate 10 is sandwiched between the upper case 7 a and the lower case 7 b , as shown in FIG. 3A. Screws 8 are inserted into through-holes 10 a formed on the control circuit substrate 10 and tightly fastened thereby to form a unitary casing 7 .
- the electronic control unit 1 as the first embodiment of the present invention has the following advantages. Since the connector 2 is positioned in the space between the driving circuit substrate 20 and the control circuit substrate 10 , the control substrate 10 can be placed sufficiently apart from the driving circuit 20 thereby to suppress heat transfer from the driving circuit substrate 20 to the control circuit substrate 10 . In other words, the space for containing the connector 2 in the casing 7 , is also utilized as the space for separating both substrates 10 , 20 from each other. Thus, the harmful heat transfer is effectively suppressed without enlarging an entire size of the electronic control unit 1 .
- both substrates 10 , 20 are electrically connected by the flexible printed-circuit-sheet 4 , the electrical connection is stably secured against vibration transferred to the casing 7 . Vibration caused by engine operation, for example, does not directly affect the electrical connection because it is absorbed by the flexibility of the flexible printed-circuit-sheet 4 . Since the soldering of the flexible printed-circuit-sheet 4 to both substrates 10 , 20 can be carried out at the same time, the manufacturing process of the electronic control unit 1 is simplified.
- the flexible printed-circuit-sheet 4 is soldered to the control circuit substrate 10 at a vicinity of the connector pins 6 , the soldering terminal portions of the control circuit substrate 10 can be simplified. At the same time, electrical resistance between the connector pins 6 and the circuit pattern can be reduced.
- FIGS. 4A- 4 C A second embodiment of the present invention will be described with reference to FIGS. 4 A- 4 C.
- the structure of the second embodiment is the same as that of the first embodiment.
- the assembling process is partly different. That is, the connector 2 is not yet mounted on the control circuit substrate 10 when the flexible printed-circuit-sheet 4 is soldered to both substrates 10 , 20 .
- FIGS. 4A and 4C FIGS. 4A and 4C (FIG. 4C is a perspective view of FIG. 4A)
- the upper case 7 a having the driving circuit substrate 20 mounted thereon and the control circuit substrate 10 are placed at a same level L.
- the flexible printed-circuit-sheet 4 is extended flat over both substrates 10 , 20 , and then it is soldered under heat and pressure in the same manner as in the first embodiment.
- the upper case 7 a is flipped over the control circuit substrate 10 as shown in FIG. 4B.
- the connector 2 is inserted through the side opening 7 e of the upper case 7 a and mounted on and connected to the control circuit substrate 10 .
- the flexible printed-circuit-sheet 4 is bent not to contact the connector 2 when the connector 2 is positioned below the flexible sheet 4 .
- the lower case 7 b is fastened to the upper case 7 a , sandwiching the control circuit substrate 10 , in the same manner as in the first embodiment.
- the flexible sheet 4 can be extended flat over both substrates 10 , 20 . Both substrates 10 , 20 can be positioned at the same level L to solder the flexible sheet 4 , and therefore, the soldering can be performed easier.
- FIGS. 5 A- 5 D A third embodiment of the present invention will be described with reference to FIGS. 5 A- 5 D.
- An electronic control unit 51 as the third embodiment is similar to the first embodiment, except that the connector 2 is replaced with a connector 32 which is mounted on the flexible printed-circuit-sheet 4 , and that the control circuit substrate 10 is replaced with a control circuit substrate 30 having a somewhat different shape.
- the connector 32 includes a flange 32 b having a hole 32 c .
- a screw hole 7 f is formed through the side wall of the upper case 7 a , and the connector 32 is fixed to the side wall by a screw 9 .
- the connector 32 is inserted into the casing 7 through the side opening 7 e so that it is positioned between the surfaces A and B, preferably between the surfaces C and B.
- a portion 32 a of the connector 32 is positioned inside the casing 7 .
- Connector pins 36 are inserted into a middle portion of the flexible printed-circuit-sheet 4 and electrically connected thereto.
- One end of the flexible sheet 4 is electrically connected to the driving circuit substrate 20 , while the other end is electrically connected to an end portion of the control circuit substrate 30 . Structures other than the above are the same as those of the first embodiment.
- the driving circuit substrate 20 and the control circuit substrate 30 are prepared in the same manner as in the foregoing embodiments, but the connector 32 is not mounted on the control circuit substrate 30 . Instead, the connector 32 is electrically connected to the flexible printed-circuit-sheet 4 at a middle portion thereof.
- the driving circuit substrate 20 is mounted on the inner surface 7 d of the upper case 7 a.
- FIG. 5B is a perspective view showing the same stage as shown in FIG. 5B.
- the connector 32 is mounted on and fixed to the sidewall of the upper case 7 a with the screw 9 .
- the upper case 7 a is flipped over the control circuit substrate 30 , so that the control circuit substrate 30 is positioned underneath the upper case 7 a as shown in FIG. 5A.
- the lower case 7 b is fixed to the upper case 7 a with screws 8 inserted into the through hole 30 a formed on the control circuit substrate 30 .
- the control circuit substrate 30 is sandwiched between the upper case 7 a and the lower case 7 b .
- the electronic control unit 51 is completed.
- the connector 32 is not mounted on the control circuit substrate 30 but is mounted on the sidewall of the upper case 7 a and electrically connected to the middle portion of the flexible sheet 4 , the height of the casing 7 can be made further smaller than that of the first embodiment.
- the inner space of the casing 7 where the connector 32 is located is utilized as the space separating both substrates 10 , 30 in the same manner as in the first embodiment, the heat transfer from the driving circuit substrate 20 to the control circuit substrate 30 is effectively suppressed without enlarging the size of the casing 7 .
- the connector 32 is electrically connected to the middle portion of the flexible sheet 4 , it is not necessary to form driving current paths on the control circuit substrate 30 .
- the driving current paths from the driving circuit substrate 20 to the connector 32 are shorter than those in the first embodiment. Therefore, heat generated in the driving current paths is further suppressed.
- the electronic control unit 51 as the fourth embodiment is similar to the third embodiment, except that noise-absorbing elements 13 are additionally mounted on the flexible printed-circuit-sheet 4 , and that an element 14 having inserting leads 14 a is additionally mounted on the control circuit substrate 30 .
- noise-absorbing elements both on the driving circuit substrate 20 and on the control circuit substrate 30 .
- the noise-absorbing elements have to be properly selected according to situations where the electronic control unit is used. If such noise absorbing elements are mounted on the substrates 20 , 30 , both substrates cannot be standardized because the noise-absorbing elements have to be changed according to the situations. Therefore, in this fourth embodiment, such noise-absorbing elements 13 are mounted on the flexible sheet 4 , thereby to simplify and standardize both substrates 20 , 30 and to reduce the manufacturing cost of the electronic control unit 51 .
- FIG. 6A showing a cross 25 sectional view of the electronic control unit 51 and FIG. 6B showing the same viewed from the side where the connector 32 is mounted
- the fourth embodiment will be described. Since the most structures are the same as those of the third embodiment, only the structure peculiar to this embodiment will be described below.
- the flexible printed-circuit-sheet 4 is composed of a mounting portion on which the connector pins 36 and the noise-absorbing elements 13 and connecting portions formed at both sides of the mounting portion.
- the connecting portions are electrically connected to both substrates 20 , 30 , respectively, in the same manner as in the third embodiment.
- the mounting portion includes an area P where the connector pins 36 are inserted and an outer area where the noise-absorbing elements 13 are surface-mounted (mounted on the surface without inserting leads).
- the element 14 having inserting leads is mounted on and connected to the control circuit substrate 30 by inserting its leads.
- the driving circuit substrate 20 is mounted on the inner surface 7 d of the upper case 7 a in the same manner as in the foregoing embodiments.
- the control elements 3 are surface-mounted on the control circuit substrate 30 , and the element 14 is also mounted on the same substrate 30 by inserting its leads 14 a .
- the connector pins 36 are inserted into and soldered on the mounting portion of the flexible sheet 4 , and the noise-absorbing elements 13 are surface-mounted thereon.
- the upper case 7 a having the driving circuit substrate 20 thereon and the control circuit substrate 30 having components mounted thereon are positioned at an even level L.
- the flexible printed-circuit-sheet 4 having the connector 32 and the noise-absorbing elements connected thereto is placed over both substrates 20 , 30 .
- the flexible sheet 4 is electrically connected to the terminal portions of both substrates 20 , 30 under heat and pressure in the same manner as in the foregoing embodiments.
- the connector 32 is turned by 90 degrees and mechanically fixed to the side wall of the upper case 7 a with screws 9 .
- the upper case 7 a is flipped over the control circuit substrate 30 to place the substrate 30 underneath the upper case 7 a .
- the upper case 7 a and the lower case 7 b are mechanically connected by screws 8 , sandwiching the control circuit substrate 30 between the upper case 7 a and the lower case 7 b .
- the electronic control unit 51 is completed.
- FIGS. 7A and 7B a fifth embodiment of the present invention will be described.
- This embodiment is almost the same as the fourth embodiment, except that the element 14 having inserting leads 14 a is mounted on and connected to the flexible printed-circuit-sheet 4 .
- the element 14 mounted on the control circuit substrate 30 in the fourth embodiment is moved to the flexible sheet 4 .
- the element 14 having inserting leads 14 a is positioned at the center of the mounting area of the flexible sheet 4 where the connector pins 36 are connected.
- the inserting leads 14 a are inserted into the flexible sheet 4 in the same direction as the connector pins 36 are inserted. Accordingly, the connector pins 36 and the element 14 can be soldered at the same time by flow-soldering.
- the control circuit substrate 30 in this embodiment only carries surface-mounting elements including the control element 3 . Therefore, those surface-mounting elements can be soldered only by reflow-soldering. If lead-inserting elements were also included on the same substrate, flow-soldering would be required in addition to the reflow-soldering.
- the lead-inserting element 14 is removed from the control circuit substrate 30 ,. the soldering process for the substrate 30 is simplified. Since the element 14 is mounted on the flexible printed-circuit-sheet 4 at a position between connecting pins 36 , the space on the flexible sheet 4 is effectively utilized.
- FIGS. 8A and 8B A sixth embodiment of the present invention will be described with reference to FIGS. 8A and 8B.
- the lead-inserting element 14 mounted on the flexible printed-circuit-sheet 4 is supported by a holder portion 32 d integrally formed with the connector 32 .
- Other structures are the same as those of the fifth embodiment.
- the holder portion 32 d is made of the same resin material as the connector 32 and is shaped in a cylinder which holds the outer periphery of the element 14 .
- the holding portion 32 d is formed to support the lead-inserting element 14 connected to the flexible printed-circuit-sheet 4 .
- a seventh embodiment of the present invention will be described with reference to FIGS. 9A and 9B.
- the flexible printed-circuit-sheet 4 used in the foregoing embodiments is divided into two portions, a hard printed-board 60 and flexible printed-sheets 64 .
- the mounting portion for mounting components including the noise-absorbing elements 13 and the lead-inserting element 14 is replaced with the hard printed-board 60 .
- the connecting portions for connecting the flexible printed-circuit-sheet 4 to both substrates 20 , 30 are replaced with the flexible printed-sheets 64 .
- Other structures are the same as those of the fifth embodiment.
- the hard printed-board 60 is made of a hard resin material such as glass-epoxy and is shaped into a rectangular shape.
- the hard printed-board 60 is mechanically supported by the connector pins 36 soldered thereon.
- the flexible printed-sheets 64 made of a flexible resin material electrically connect the hard printed-board 60 to both substrates 20 , 30 .
- the components such as the noise-absorbing elements 13 and the lead-inserting element 14 are mounted on and electrically connected to the hard printed-board 60 , the electrical connections of those components are more stable against vibration.
- the present invention is not limited to the foregoing embodiments, but those embodiments may be variously modified.
- the lead-inserting element 14 which is mounted in the center portion of the flexible printed-circuit-sheet 4 in the fourth embodiment may be moved to an outside of the area P where the connector pins 36 are connected.
- those components such as the noise-absorbing elements 13 and the lead-inserting element 14 may be placed both in the area P and the outside thereof.
- the electronic control unit according to the present invention is explained to be used in the automobile engine control, it may be used for other purposes.
Abstract
Description
- This application is based upon and claims benefit of priority of Japanese Patent Applications No. 2000-45907 filed on Feb. 23, 2000 and No. 2000-72356 filed on Mar. 15, 2000, the contents of which are incorporated herein by reference.
- 1. Field of the Invention
- The present invention relates to an electronic control unit for controlling operation of actuators and to a method of manufacturing the same.
- 2. Description of Related Art
- Electronic control units for use in various controls, such as automotive engine control and transmission control, are generally known. The electronic control unit controls operation of actuators such as electromagnetic solenoids by supplying power thereto based on signals fed to and processed in the electronic control unit. Recent electronic controls for an automotive vehicle are becoming more sophisticated and multi-functional. Electric power to be controlled by driving elements in the electronic control unit is also becoming high. An amount of heat generated in the driving elements such as power transistors or power ICs contained in the electronic control unit becomes high. Such heat is transferred to control elements such as microcomputers contained in the same electronic control unit.
- An example of conventional electronic control units is shown in FIG. 1. A
circuit substrate 40 on which adriving element 5 and acontrol element 3 are mounted is contained in acasing 7. Aconnector 2 for electrically connecting the electronic control unit to outside sensors and actuators is also mounted in the casing. Heat generated in thedriving element 5 such as a power transistor is transferred to thecontrol element 3 such as a microcomputer, thereby heating thecontrol element 3. If thecontrol element 3 is excessively heated, its operation stability cannot be maintained. It could be possible to enlarge thecircuit substrate 40 to suppress the heat transfer from thedriving element 5 to thecontrol element 3. However, it is not preferable, or may not be possible, to enlarge the size of the electronic control unit from viewpoints of a mounting space and a cost of the electronic control unit. - The present invention has been made in view of the above-mentioned problem, and an object of the present invention is to provide an improved electronic control unit, in which the heat transfer from the driving elements to the control elements is suppressed without enlarging the size of the electronic control unit.
- The electronic control unit according to the present invention is composed of a metal casing, a driving circuit substrate, a control circuit substrate, a flexible printed-circuit sheet connecting both substrates, and a connector for connecting the electronic control unit to outside actuators and sensors. The control circuit substrate includes control elements such as a microcomputer for processing signals fed from the outside sensors and for supplying control signals to the driving circuit substrate. The driving circuit substrate includes driving elements such as power transistors for supplying electric power to the outside actuators based on the control signals fed from the control circuit substrate.
- The metal casing has a heat dissipation plate on which the driving circuit substrate generating a large amount of heat is mounted. The control circuit substrate that generates substantially no heat is contained in the casing apart from the driving circuit substrate. A separating space for suppressing heat transfer from the driving circuit substrate to the control circuit substrate is formed between both substrates. The connector is positioned in the separating space. Thus, the separating space in the casing is also utilized as a space for containing the connector. Both substrates are electrically connected by a flexible printed-circuit-sheet which absorbs vibration energy to protect electrical connections. The flexible printed-circuit-sheet is connected to the control circuit substrate at a vicinity of connector pins connecting the connector to the control circuit substrate to reduce electrical resistance in the circuit.
- The connector may be mounted on the control circuit substrate and electrically connected thereto. In this case, preferably, both substrates are first connected by the flexible printed-circuit-sheet, and then the connector is mounted on the control circuit substrate to simplify the manufacturing process.
- Alternatively, the connector may be mounted on the casing and electrically connected to the flexible printed-circuit-sheet. In this case, preferably, the connector is electrically connected to the flexible printed-circuit-sheet, and then the flexible sheet is electrically connected to both substrates. After that, the connector is mounted on the casing. Elements for absorbing noise coming into the electronic control unit may be surface-mounted on the flexible sheet. Components having inserting leads may also be mounted on the flexible sheet, removing such components from the control circuit board. If no such component is mounted on the control circuit substrate, electrical connections on the control circuit substrate can be carried out only by reflow-soldering. Further, a portion of the flexible sheet on which electric components are mounted may be made of a hard printed-board to secure stable electrical connections against vibration. Components mounted on the flexible sheet may be supported by a holder formed integrally with the connector to secure a higher mechanical strength.
- According to the present invention, the driving circuit substrate and the control circuit substrate are positioned in the casing with a separating space therebetween, and the connector is disposed within the separating space. In other words, the separating space for suppressing the heat transfer is also utilized as a space for containing the connector therein. Accordingly, the heat transfer is effectively suppressed without enlarging the size of the electronic control unit.
- Other objects and features of the present invention will become more readily apparent from a better understanding of the preferred embodiments described below with reference to the following drawings.
- FIG. 1 is a cross-sectional view showing a conventional electronic control unit;
- FIG. 2A is a cross-sectional view showing an electronic control unit as a comparative example to embodiments of the present invention;
- FIG. 2B is a plan view of the electronic control unit shown in FIG. 2A with its upper case removed;
- FIG. 3A is a cross-sectional view showing an electronic control unit as a first embodiment of the present invention;
- FIG. 3B is a cross-sectional view showing one stage of assembling the electronic control unit shown in FIG. 3A;
- FIG. 3C is a perspective view showing the same assembling stage as shown in FIG. 3B;
- FIG. 4A is a cross-sectional view showing one stage of assembling an electronic control unit as a second embodiment of the present invention;
- FIG. 4B is a cross-sectional view showing the next assembling stage following the stage shown in FIG. 4A;
- FIG. 4C is a perspective view showing the same assembling stage as shown in FIG. 4A;
- FIG. 5A is a cross-sectional view showing an electronic control unit as a third embodiment of the present invention;
- FIG. 5B is a cross-sectional view showing one stage of assembling the electronic control unit shown in FIG. 5A;
- FIG. 5C is a cross-sectional view showing the next assembling stage following the stage shown in FIG. 5B;
- FIG. 5D is a perspective view showing the same assembling stage as shown in FIG. 5B;
- FIG. 6A is a cross-sectional view showing an electronic control unit as a fourth embodiment of the present invention;
- FIG. 6B is a cross-sectional view showing the electronic control unit shown in FIG. 6A, viewed from a connector side;
- FIG. 6C is a cross-sectional view showing one stage of assembling the electronic control unit shown in FIG. 6A;
- FIG. 6D is a cross-sectional view showing the next assembling stage following the stage shown in FIG. 6C;
- FIG. 7A is a cross-sectional view showing an electronic control unit as a fifth embodiment of the present invention;
- FIG. 7B is a cross-sectional view showing the electronic control unit shown in FIG. 7A, viewed from a connector side;
- FIG. 8A is a cross-sectional view showing an electronic control unit as a sixth embodiment of the present invention;
- FIG. 8B is a cross-sectional view showing the electronic control unit shown in FIG. 8A, viewed from a connector side;
- FIG. 9A is a cross-sectional view showing an electronic control unit as a seventh embodiment of the present invention;
- FIG. 9B is a cross-sectional view showing the electronic control unit shown in FIG. 9A, viewed from a connector side; and
- FIG. 10 is a cross-sectional view showing an example of modified forms of the embodiments shown above.
- One solution for suppressing heat transfer from driving elements to control elements contained in the same casing is to divide the
circuit substrate 40 shown in FIG. 1 into a substrate carrying only the control elements thereon and another substrate carrying the driving elements thereon. - One example of such arrangements is shown in FIGS. 2A and 2B.
- FIG. 2A is a cross-sectional view and FIG. 2B is a plan view with an upper case removed. A
control circuit substrate 10 carrying thecontrol element 3 is supported in the middle portion of thecasing 7, while adriving circuit substrate 20 carrying thedriving elements 5 is mounted on bottom heat dissipation plate of thecasing 7. Both substrates are electrically connected by a flexible printed-circuit-sheet 4. Aconnector 2 for electrically connecting the electronic control unit to outside sensors and actuators is mounted on and electrically connected to thecontrol circuit substrate 10. - Since the driving
circuit substrate 20 is positioned apart from thecontrol circuit substrate 10 with a certain space therebetween, the heat transfer from thesubstrate 20 to thesubstrate 10 can be suppressed. If it is possible to make the space between twosubstrates casing 7 cannot be shortened because there is positioned theconnector 2. - A first embodiment of the present invention shown in FIG. 3A is designed to further improve the example shown in FIGS. 2A and 2B. The first embodiment of the present invention will be described in detail with reference to FIGS.3A-3C.
- First, referring to FIG. 3A, the structure of an electronic control unit1 will be described. The electronic control unit 1 is used for controlling operation of various actuators of an
automotive engine 100, such as ignition plugs and electromagnetic solenoids. The electronic control unit 1 is electrically connected to the actuators and sensors through acable 102. The electronic control unit 1 is composed of acasing 7, acontrol circuit substrate 10 carryingcontrol elements 3 thereon, a drivingcircuit substrate 20 carryingdriving elements 5 thereon, and aconnector 2 coupled to thecable 102. Bothsubstrates sheet 4. - The
casing 7 is composed of anupper case 7 a and alower case 7 b, and bothcases screws 8. Thecontrol circuit substrate 10 is mounted in thecasing 7, being inserted between theupper case 7 a and thelower case 7 b. The drivingcircuit substrate 20 is mounted on aninner wall 7 d of anupper wall 7 c of thecasing 7. Theconnector 2 is inserted through aside opening 7 e of theupper case 7 a so that itsportion 2 a is positioned inside thecasing 7, and is mounted on thesubstrate 10. Theconnector 2 is positioned in a space between a surface A (theinner surface 7 d of theupper wall 7 c) and a surface B (the upper surface of the substrate 10), preferably in the space between a surface C (the lower surface of the substrate 20) and the surface B. A plurality ofconnector pins 6 extending from theconnector 2 are inserted into thecontrol circuit substrate 10 and electrically connected thereto. - The
control elements 3 consist of an one-chip microcomputer to which signals from various sensors are fed. The signals fed to the microcomputer are processed to form control signals to be supplied to thedriving elements 5. Thecontrol elements 3 also perform communication with various electronic components mounted on the automobile through thecable 102. Thecontrol circuit substrate 10 on which thecontrol elements 3 are mounted is made of a resin board such as an epoxy-impregnated glass-cloth, and control circuits are formed thereon. Electronic components (not shown) other than thecontrol elements 3 are also mounted on both sides of thecontrol circuit substrate 10. - The
connector 2 is mounted on thecontrol circuit substrate 10, and the connector pins 6 are electrically connected to thecontrol circuit substrate 10. As shown in FIG. 3A, the connector pins 6 are connected to thecontrol circuit substrate 10 at its left side end, and one end of the flexible printed-circuit sheet 4 is electrically connected to thecontrol circuit substrate 10 by soldering at a vicinity of the position where the connector pins 6 are connected. The other end of the flexible printed-circuit sheet 4 is electrically connected to thedriving circuit substrate 20. The flexible printed-circuit sheet 4 is bent and connected to bothsubstrates upper wall 7 c. - The
driving elements 5 mounted on thedriving circuit substrate 20 are so-called switching elements for supplying electric power to the outside actuators. The electric power is supplied from an on-board battery (not shown) through the driving elements based on the control signals fed from thecontrol elements 3. The drivingcircuit substrate 20 is made of a heat-conductive ceramic plate on which driving circuits are formed. Components (not shown) other than the drivingelements 5 are also mounted on thedriving circuit substrate 20. The driving circuit substrate is mounted on theinner surface 7 d of theupper wall 7 c in close contact therewith, so that heat generated in thedriving elements 5 is easily transferred to thecasing 7 and dissipated therefrom. Thecasing 7 is made of a metallic material such as cast aluminum, and itsupper wall 7 c serves as a heat-dissipation plate. - A process of assembling the electronic control unit1 will be described with reference to FIGS. 3B and 3C. The driving
elements 5 and other components are mounted on and connected to thedriving circuit substrate 20. The drivingcircuit substrate 20 is bonded on theinner surface 7 d of theupper wall 7 c with a heat-conductive adhesive which is cured by applying heat (e.g., 150° C.) for a certain time (e.g., 30 minutes). Heat resistance between theupper wall 7 c and thedriving circuit substrate 20 is made as small as possible. On the other hand, thecontrol elements 3 and other components are mounted on and connected to thecontrol circuit substrate 10. Theconnector 2 is also mounted on and connected to thecontrol circuit substrate 10. - Then, the
upper case 7 a carrying the drivingcircuit substrate 20 thereon and thecontrol substrate 10 are positioned as shown in FIG. 3B. The flexible printed-circuit-sheet 4 is placed over the bothsubstrates side opening 7 e of theupper case 7 a. Both ends of the flexible printed-circuit-sheet 4 are pressed down on the terminal portions of bothcircuit substrates sheets 4 is soldered to bothsubstrates substrates sheet 4 are pressed down on the solder by heated jigs S. Since theconnector 2 mounted on thecontrol circuit substrate 10 prevents the flexible printed-circuit-sheet 4 from being extended flat, theupper case 7 a and thecontrol circuit substrate 10 are positioned as shown in FIGS. 3B and 3C (FIG. 3C is a perspective view of FIG. 3B). - After the flexible printed-circuit-
sheet 4 is soldered, theupper case 7 a is flipped over thecontrol circuit substrate 10 so that theinner surface 7 d of theupper case 7 a faces thecontrol circuit substrate 10. Then, thecontrol circuit substrate 10 is sandwiched between theupper case 7 a and thelower case 7 b, as shown in FIG. 3A.Screws 8 are inserted into through-holes 10 a formed on thecontrol circuit substrate 10 and tightly fastened thereby to form aunitary casing 7. - The electronic control unit1 as the first embodiment of the present invention has the following advantages. Since the
connector 2 is positioned in the space between the drivingcircuit substrate 20 and thecontrol circuit substrate 10, thecontrol substrate 10 can be placed sufficiently apart from the drivingcircuit 20 thereby to suppress heat transfer from the drivingcircuit substrate 20 to thecontrol circuit substrate 10. In other words, the space for containing theconnector 2 in thecasing 7, is also utilized as the space for separating bothsubstrates - Since both
substrates sheet 4, the electrical connection is stably secured against vibration transferred to thecasing 7. Vibration caused by engine operation, for example, does not directly affect the electrical connection because it is absorbed by the flexibility of the flexible printed-circuit-sheet 4. Since the soldering of the flexible printed-circuit-sheet 4 to bothsubstrates - Further, since the flexible printed-circuit-
sheet 4 is soldered to thecontrol circuit substrate 10 at a vicinity of the connector pins 6, the soldering terminal portions of thecontrol circuit substrate 10 can be simplified. At the same time, electrical resistance between the connector pins 6 and the circuit pattern can be reduced. - A second embodiment of the present invention will be described with reference to FIGS.4A-4C. The structure of the second embodiment is the same as that of the first embodiment. However, the assembling process is partly different. That is, the
connector 2 is not yet mounted on thecontrol circuit substrate 10 when the flexible printed-circuit-sheet 4 is soldered to bothsubstrates upper case 7 a having the drivingcircuit substrate 20 mounted thereon and thecontrol circuit substrate 10 are placed at a same level L. The flexible printed-circuit-sheet 4 is extended flat over bothsubstrates - Then, the
upper case 7 a is flipped over thecontrol circuit substrate 10 as shown in FIG. 4B. Then, theconnector 2 is inserted through theside opening 7 e of theupper case 7 a and mounted on and connected to thecontrol circuit substrate 10. The flexible printed-circuit-sheet 4 is bent not to contact theconnector 2 when theconnector 2 is positioned below theflexible sheet 4. Then, thelower case 7 b is fastened to theupper case 7 a, sandwiching thecontrol circuit substrate 10, in the same manner as in the first embodiment. - Since, in the second embodiment, the
connector 2 is not on the way of theflexible sheet 4 in the soldering process, theflexible sheet 4 can be extended flat over bothsubstrates substrates flexible sheet 4, and therefore, the soldering can be performed easier. - A third embodiment of the present invention will be described with reference to FIGS.5A-5D. An
electronic control unit 51 as the third embodiment is similar to the first embodiment, except that theconnector 2 is replaced with aconnector 32 which is mounted on the flexible printed-circuit-sheet 4, and that thecontrol circuit substrate 10 is replaced with acontrol circuit substrate 30 having a somewhat different shape. - As shown in FIG. 5A, the
connector 32 includes aflange 32 b having ahole 32 c. Ascrew hole 7 f is formed through the side wall of theupper case 7 a, and theconnector 32 is fixed to the side wall by ascrew 9. Theconnector 32 is inserted into thecasing 7 through theside opening 7 e so that it is positioned between the surfaces A and B, preferably between the surfaces C and B. Aportion 32 a of theconnector 32 is positioned inside thecasing 7. Connector pins 36 are inserted into a middle portion of the flexible printed-circuit-sheet 4 and electrically connected thereto. One end of theflexible sheet 4 is electrically connected to thedriving circuit substrate 20, while the other end is electrically connected to an end portion of thecontrol circuit substrate 30. Structures other than the above are the same as those of the first embodiment. - Referring to FIGS.5B-5D, a process of assembling the electronic control unit S will be described. First, the driving
circuit substrate 20 and thecontrol circuit substrate 30 are prepared in the same manner as in the foregoing embodiments, but theconnector 32 is not mounted on thecontrol circuit substrate 30. Instead, theconnector 32 is electrically connected to the flexible printed-circuit-sheet 4 at a middle portion thereof. The drivingcircuit substrate 20 is mounted on theinner surface 7 d of theupper case 7 a. - Then, as shown in FIG. 5B, the
upper case 7 a and thecontrol circuit substrate 30 are positioned in the same horizontal level L. Then, theflexible sheet 4 carrying theconnector 32 thereon is placed over bothsubstrates substrates connector 32 is not an obstacle to stretch theflexible sheet 4 over bothsubstrates substrates - Then, as shown in FIG. 5C, the
connector 32 is mounted on and fixed to the sidewall of theupper case 7 a with thescrew 9. Then, theupper case 7 a is flipped over thecontrol circuit substrate 30, so that thecontrol circuit substrate 30 is positioned underneath theupper case 7 a as shown in FIG. 5A. Then, thelower case 7 b is fixed to theupper case 7 a withscrews 8 inserted into the throughhole 30 a formed on thecontrol circuit substrate 30. Thecontrol circuit substrate 30 is sandwiched between theupper case 7 a and thelower case 7 b. Thus, theelectronic control unit 51 is completed. - Since, in this third embodiment, the
connector 32 is not mounted on thecontrol circuit substrate 30 but is mounted on the sidewall of theupper case 7 a and electrically connected to the middle portion of theflexible sheet 4, the height of thecasing 7 can be made further smaller than that of the first embodiment. The inner space of thecasing 7 where theconnector 32 is located is utilized as the space separating bothsubstrates circuit substrate 20 to thecontrol circuit substrate 30 is effectively suppressed without enlarging the size of thecasing 7. Since theconnector 32 is electrically connected to the middle portion of theflexible sheet 4, it is not necessary to form driving current paths on thecontrol circuit substrate 30. In addition, the driving current paths from the drivingcircuit substrate 20 to theconnector 32 are shorter than those in the first embodiment. Therefore, heat generated in the driving current paths is further suppressed. - With reference to FIGS.6A-6D, a fourth embodiment of the present invention will be described. The
electronic control unit 51 as the fourth embodiment is similar to the third embodiment, except that noise-absorbingelements 13 are additionally mounted on the flexible printed-circuit-sheet 4, and that anelement 14 having insertingleads 14 a is additionally mounted on thecontrol circuit substrate 30. - To suppress or absorb noises entering into the
electronic control unit 51 through thecable 102 and theconnectors 32, it is often required to dispose noise-absorbing elements both on thedriving circuit substrate 20 and on thecontrol circuit substrate 30. The noise-absorbing elements have to be properly selected according to situations where the electronic control unit is used. If such noise absorbing elements are mounted on thesubstrates elements 13 are mounted on theflexible sheet 4, thereby to simplify and standardize bothsubstrates electronic control unit 51. - First, referring to FIG. 6A showing a cross25 sectional view of the
electronic control unit 51 and FIG. 6B showing the same viewed from the side where theconnector 32 is mounted, the fourth embodiment will be described. Since the most structures are the same as those of the third embodiment, only the structure peculiar to this embodiment will be described below. - The flexible printed-circuit-
sheet 4 is composed of a mounting portion on which the connector pins 36 and the noise-absorbingelements 13 and connecting portions formed at both sides of the mounting portion. The connecting portions are electrically connected to bothsubstrates elements 13 are surface-mounted (mounted on the surface without inserting leads). Theelement 14 having inserting leads is mounted on and connected to thecontrol circuit substrate 30 by inserting its leads. - A process of assembling the
electronic control unit 51 will be briefly described with reference to FIGS. 6C and 6D. The drivingcircuit substrate 20 is mounted on theinner surface 7 d of theupper case 7 a in the same manner as in the foregoing embodiments. Thecontrol elements 3 are surface-mounted on thecontrol circuit substrate 30, and theelement 14 is also mounted on thesame substrate 30 by inserting itsleads 14 a. The connector pins 36 are inserted into and soldered on the mounting portion of theflexible sheet 4, and the noise-absorbingelements 13 are surface-mounted thereon. - Then, as shown in FIG. 6C, the
upper case 7 a having the drivingcircuit substrate 20 thereon and thecontrol circuit substrate 30 having components mounted thereon are positioned at an even level L. The flexible printed-circuit-sheet 4 having theconnector 32 and the noise-absorbing elements connected thereto is placed over bothsubstrates flexible sheet 4 is electrically connected to the terminal portions of bothsubstrates connector 32 is turned by 90 degrees and mechanically fixed to the side wall of theupper case 7 a with screws 9. Then, theupper case 7 a is flipped over thecontrol circuit substrate 30 to place thesubstrate 30 underneath theupper case 7 a. Then, theupper case 7 a and thelower case 7 b are mechanically connected byscrews 8, sandwiching thecontrol circuit substrate 30 between theupper case 7 a and thelower case 7 b. Thus, theelectronic control unit 51 is completed. - The same advantages as those of the third embodiment are obtained in this embodiment, too. In addition, since the noise-absorbing
elements 13 are mounted on the flexible printed-circuit-sheet 4, noises entering into theelectronic control unit 51 are absorbed by those elements without mounting respective noise-absorbing elements on bothsubstrates flexible sheet 4 in the area P while the noise-absorbingelements 13 are mounted on the area outside the area P, the process of mounting those components on the flexible sheets is easily carried out. - Referring to FIGS. 7A and 7B, a fifth embodiment of the present invention will be described. This embodiment is almost the same as the fourth embodiment, except that the
element 14 having insertingleads 14 a is mounted on and connected to the flexible printed-circuit-sheet 4. In other words, theelement 14 mounted on thecontrol circuit substrate 30 in the fourth embodiment is moved to theflexible sheet 4. - As shown in FIG. 7B, the
element 14 having insertingleads 14 a is positioned at the center of the mounting area of theflexible sheet 4 where the connector pins 36 are connected. The inserting leads 14 a are inserted into theflexible sheet 4 in the same direction as the connector pins 36 are inserted. Accordingly, the connector pins 36 and theelement 14 can be soldered at the same time by flow-soldering. Thecontrol circuit substrate 30 in this embodiment only carries surface-mounting elements including thecontrol element 3. Therefore, those surface-mounting elements can be soldered only by reflow-soldering. If lead-inserting elements were also included on the same substrate, flow-soldering would be required in addition to the reflow-soldering. - Since, in the fifth embodiment, the lead-inserting
element 14 is removed from thecontrol circuit substrate 30,. the soldering process for thesubstrate 30 is simplified. Since theelement 14 is mounted on the flexible printed-circuit-sheet 4 at a position between connectingpins 36, the space on theflexible sheet 4 is effectively utilized. - A sixth embodiment of the present invention will be described with reference to FIGS. 8A and 8B. In this embodiment, the lead-inserting
element 14 mounted on the flexible printed-circuit-sheet 4 is supported by aholder portion 32 d integrally formed with theconnector 32. Other structures are the same as those of the fifth embodiment. Theholder portion 32 d is made of the same resin material as theconnector 32 and is shaped in a cylinder which holds the outer periphery of theelement 14. - There is a possibility that the electrical connection of the lead-inserting
element 14 carried by theflexible sheet 4 would be loosened if thecasing 7 is excessively vibrated. For avoiding such a possibility, the holdingportion 32 d is formed to support the lead-insertingelement 14 connected to the flexible printed-circuit-sheet 4. - A seventh embodiment of the present invention will be described with reference to FIGS. 9A and 9B. In this embodiment, the flexible printed-circuit-
sheet 4 used in the foregoing embodiments is divided into two portions, a hard printed-board 60 and flexible printed-sheets 64. The mounting portion for mounting components including the noise-absorbingelements 13 and the lead-insertingelement 14 is replaced with the hard printed-board 60. The connecting portions for connecting the flexible printed-circuit-sheet 4 to bothsubstrates sheets 64. Other structures are the same as those of the fifth embodiment. - The hard printed-
board 60 is made of a hard resin material such as glass-epoxy and is shaped into a rectangular shape. The hard printed-board 60 is mechanically supported by the connector pins 36 soldered thereon. The flexible printed-sheets 64 made of a flexible resin material electrically connect the hard printed-board 60 to bothsubstrates - Since, in this embodiment, the components such as the noise-absorbing
elements 13 and the lead-insertingelement 14 are mounted on and electrically connected to the hard printed-board 60, the electrical connections of those components are more stable against vibration. - The present invention is not limited to the foregoing embodiments, but those embodiments may be variously modified. For example, as shown in FIG. 10, the lead-inserting
element 14 which is mounted in the center portion of the flexible printed-circuit-sheet 4 in the fourth embodiment may be moved to an outside of the area P where the connector pins 36 are connected. Alternatively, those components such as the noise-absorbingelements 13 and the lead-insertingelement 14 may be placed both in the area P and the outside thereof. Though the electronic control unit according to the present invention is explained to be used in the automobile engine control, it may be used for other purposes. - While the present invention has been shown and described with reference to the foregoing preferred embodiments, it will be apparent to those skilled in the art that changes in form and detail may be made therein without departing from the scope of the invention as defined in the appended claims.
Claims (15)
Applications Claiming Priority (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2000-045907 | 2000-02-23 | ||
JP2000045907A JP2001237575A (en) | 2000-02-23 | 2000-02-23 | Electronic control apparatus and its manufacturing method |
JP2000-45907 | 2000-02-23 | ||
JP2000072356A JP2001267022A (en) | 2000-03-15 | 2000-03-15 | Electronic controller |
JP2000-072356 | 2000-03-15 |
Publications (2)
Publication Number | Publication Date |
---|---|
US20010015887A1 true US20010015887A1 (en) | 2001-08-23 |
US6442027B2 US6442027B2 (en) | 2002-08-27 |
Family
ID=26585908
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US09/739,961 Expired - Fee Related US6442027B2 (en) | 2000-02-23 | 2000-12-20 | Electronic control unit having connector positioned between two circuit substrates |
Country Status (2)
Country | Link |
---|---|
US (1) | US6442027B2 (en) |
DE (1) | DE10107711A1 (en) |
Cited By (16)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6802721B2 (en) | 2002-01-31 | 2004-10-12 | Denso Corporation | Electronic device in which a circuit board and an electric connector are electrically connected by a flexible printed wiring board |
US20090052139A1 (en) * | 2007-08-23 | 2009-02-26 | Kuping Lai | Heat-Dissipation Apparatus For Communication Device With Card Slot |
US20090284936A1 (en) * | 2008-05-15 | 2009-11-19 | Semikron Elektronik Gmbh & Co. Kg | Combination of a Main Carrier and a Printed Circuit Board with Components |
US20110044005A1 (en) * | 2007-12-19 | 2011-02-24 | Robert Bosch Gmbh | Control unit housing |
WO2011150874A3 (en) * | 2011-06-14 | 2012-05-10 | 华为终端有限公司 | Device with heat insulation structure |
EP2467001A1 (en) * | 2010-12-17 | 2012-06-20 | SEMIKRON Elektronik GmbH & Co. KG | Circuit assembly with at least two sub-modules |
CN102781199A (en) * | 2011-05-10 | 2012-11-14 | 华为终端有限公司 | Protective method and terminal device for electronic component |
WO2014111313A1 (en) * | 2013-01-17 | 2014-07-24 | Continental Automotive Gmbh | Device for receiving electronic components |
US20140347819A1 (en) * | 2011-12-21 | 2014-11-27 | Robert Bosch Gmbh | Electronics Module for a Vehicle |
US20150022976A1 (en) * | 2011-11-08 | 2015-01-22 | Robert Bosch Gmbh | Electronic Module for a Control Unit |
CN104620454A (en) * | 2012-09-11 | 2015-05-13 | 株式会社自动网络技术研究所 | Electrical connection box |
US20150210155A1 (en) * | 2014-01-29 | 2015-07-30 | Dr. Ing. H.C. F. Porsche Aktiengesellschaft | Cooling device for a hybrid module of a hybrid vehicle |
US20170290178A1 (en) * | 2014-09-03 | 2017-10-05 | Conti Temic Microelectronic Gmbh | Control Unit Device For A Motor Vehicle And Method For Manufacturing Such A Device |
US10424947B2 (en) | 2017-02-13 | 2019-09-24 | Yazaki Corporation | Battery monitoring device |
CN114128051A (en) * | 2019-07-19 | 2022-03-01 | 浩亭电子有限公司 | Contact element for electrically connecting circuit boards and method for assembling a circuit board assembly |
US20220360915A1 (en) * | 2021-05-04 | 2022-11-10 | Sivantos Pte. Ltd. | Charging device of a hearing aid and system with the charging device |
Families Citing this family (30)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE10110948A1 (en) * | 2001-03-07 | 2002-09-19 | Siemens Ag | Mechatronic transmission control |
US6814588B1 (en) * | 2001-12-05 | 2004-11-09 | Adaptec, Inc. | Overmold cable terminator |
US7019387B1 (en) * | 2002-02-14 | 2006-03-28 | Amkor Technology, Inc. | Lead-frame connector and circuit module assembly |
DE10220047A1 (en) * | 2002-05-04 | 2003-11-20 | Jungheinrich Ag | Drive system with converter control for low-voltage three-phase motors |
US6618261B1 (en) * | 2002-06-04 | 2003-09-09 | Ford Global Technologies, Llc | Electrical sensor mount |
JP3864873B2 (en) * | 2002-08-09 | 2007-01-10 | 株式会社デンソー | Electronic control unit |
DE10318728A1 (en) * | 2003-04-25 | 2004-11-11 | Conti Temic Microelectronic Gmbh | Electrical connection arrangement e.g. for motor vehicle door or seat, has ribbon cable with conductors stripped at two or more separate contact sections, and electrically connected to contact elements connecting conductor to circuit board |
TWM240768U (en) * | 2003-05-23 | 2004-08-11 | Lite On Technology Corp | Shell device with printing circuit unit |
DE10324047B4 (en) * | 2003-05-27 | 2013-02-28 | Continental Automotive Gmbh | Electronic unit and method for manufacturing an electronic unit |
US6894891B2 (en) * | 2003-06-30 | 2005-05-17 | Lear Corporation | Smart junction box for automobile |
JP2005166765A (en) * | 2003-11-28 | 2005-06-23 | Toshiba Corp | Electronic device and circuit module device |
DE102005006975B4 (en) * | 2005-02-16 | 2009-06-25 | Knorr-Bremse Systeme für Nutzfahrzeuge GmbH | Mechatronic assembly |
US7903417B2 (en) * | 2006-10-10 | 2011-03-08 | Deere & Company | Electrical circuit assembly for high-power electronics |
US20080084671A1 (en) * | 2006-10-10 | 2008-04-10 | Ronnie Dean Stahlhut | Electrical circuit assembly for high-power electronics |
US7291023B1 (en) * | 2006-11-21 | 2007-11-06 | Autoliv Asp, Inc. | Electric vehicle motion sensor |
US7839656B2 (en) * | 2007-06-15 | 2010-11-23 | Sony Ericsson Mobile Communications Ab | Shielded circuit assembly and method |
US20090091889A1 (en) * | 2007-10-09 | 2009-04-09 | Oman Todd P | Power electronic module having improved heat dissipation capability |
KR20100069969A (en) * | 2008-12-17 | 2010-06-25 | 삼성전자주식회사 | Installing structure of memory for portable terminal |
DE102010005303B4 (en) * | 2010-01-21 | 2016-12-29 | Continental Automotive Gmbh | Integrated control unit with plastic housing |
DE102010005305B4 (en) * | 2010-01-21 | 2016-12-29 | Continental Automotive Gmbh | Integrated control unit with simplified heat dissipation |
DE102010034975A1 (en) * | 2010-08-20 | 2012-02-23 | Hella Kgaa Hueck & Co. | Electronic circuit for e.g. transmission and/or receiving device in motor car, has printed circuit boards held by fixing pins that are arranged in housing, where fixing pins include set of layers that is arranged corresponding to boards |
DE102011122363B4 (en) | 2011-12-23 | 2019-03-21 | Thomas Magnete Gmbh | Electric control for electromagnets |
EP2728982B1 (en) * | 2012-10-30 | 2017-07-26 | Continental Automotive GmbH | Circuit board module for a control device, control device for a motor vehicle and signal processing assembly |
JP5776856B2 (en) * | 2012-11-09 | 2015-09-09 | 日本精工株式会社 | connector |
JP5971267B2 (en) * | 2013-02-26 | 2016-08-17 | 株式会社デンソー | Pressure sensor and manufacturing method thereof |
DE102015223550A1 (en) * | 2015-11-27 | 2017-06-01 | Robert Bosch Gmbh | Electronic module and method for manufacturing an electronic module with a fluid-tight housing |
JP7022265B2 (en) * | 2017-10-25 | 2022-02-18 | 株式会社島津製作所 | Vacuum pump |
JP7087418B2 (en) * | 2018-02-02 | 2022-06-21 | 株式会社島津製作所 | Vacuum pump |
US10566722B2 (en) * | 2018-07-18 | 2020-02-18 | Getac Technology Corporation | Float-type connecting module and float-type docking device having the module |
JP6880128B2 (en) * | 2019-09-04 | 2021-06-02 | 三菱電機株式会社 | Electronic equipment unit |
Family Cites Families (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4758805A (en) * | 1983-10-28 | 1988-07-19 | Nippondenso Co., Ltd. | High frequency interference prevention filter for electric instruments |
US4689721A (en) * | 1986-01-10 | 1987-08-25 | Trw Inc. | Dual printed circuit board module |
US4858071A (en) * | 1987-02-24 | 1989-08-15 | Nissan Motor Co., Ltd. | Electronic circuit apparatus |
JPH0666408B2 (en) | 1987-12-04 | 1994-08-24 | 富士電機株式会社 | Multilayer semiconductor device |
US4811165A (en) * | 1987-12-07 | 1989-03-07 | Motorola, Inc. | Assembly for circuit modules |
JP2690533B2 (en) * | 1988-12-23 | 1997-12-10 | 三洋電機株式会社 | Connector structure of hybrid integrated circuit |
US5103375A (en) * | 1990-02-05 | 1992-04-07 | Motorola, Inc. | Electronic module assembly and method of manufacture |
DE69227066T2 (en) | 1991-05-31 | 1999-06-10 | Denso Corp | Electronic device |
JPH0621330A (en) | 1992-06-30 | 1994-01-28 | Mitsubishi Electric Corp | Semiconductor power module |
JP2956363B2 (en) | 1992-07-24 | 1999-10-04 | 富士電機株式会社 | Power semiconductor device |
US5362243A (en) * | 1992-09-01 | 1994-11-08 | Huss Charles G | Air data transducer |
JP3691057B2 (en) * | 1993-06-26 | 2005-08-31 | ローベルト ボツシユ ゲゼルシヤフト ミツト ベシユレンクテル ハフツング | Mounting control device |
US5605477A (en) * | 1995-01-13 | 1997-02-25 | The Whitaker Corporation | Flexible etched circuit assembly |
US5959839A (en) * | 1997-01-02 | 1999-09-28 | At&T Corp | Apparatus for heat removal using a flexible backplane |
-
2000
- 2000-12-20 US US09/739,961 patent/US6442027B2/en not_active Expired - Fee Related
-
2001
- 2001-02-19 DE DE10107711A patent/DE10107711A1/en not_active Withdrawn
Cited By (26)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6802721B2 (en) | 2002-01-31 | 2004-10-12 | Denso Corporation | Electronic device in which a circuit board and an electric connector are electrically connected by a flexible printed wiring board |
US20090052139A1 (en) * | 2007-08-23 | 2009-02-26 | Kuping Lai | Heat-Dissipation Apparatus For Communication Device With Card Slot |
US8792242B2 (en) * | 2007-12-19 | 2014-07-29 | Robert Bosch Gmbh | Control unit housing |
US20110044005A1 (en) * | 2007-12-19 | 2011-02-24 | Robert Bosch Gmbh | Control unit housing |
US8344270B2 (en) * | 2008-05-15 | 2013-01-01 | Semikron Elektronik Gmbh & Co., Kg | Combination of a main carrier and a printed circuit board with components |
US20090284936A1 (en) * | 2008-05-15 | 2009-11-19 | Semikron Elektronik Gmbh & Co. Kg | Combination of a Main Carrier and a Printed Circuit Board with Components |
EP2467001A1 (en) * | 2010-12-17 | 2012-06-20 | SEMIKRON Elektronik GmbH & Co. KG | Circuit assembly with at least two sub-modules |
CN102548208A (en) * | 2010-12-17 | 2012-07-04 | 赛米控电子股份有限公司 | Circuit assembly with at least two sub-modules |
CN102781199A (en) * | 2011-05-10 | 2012-11-14 | 华为终端有限公司 | Protective method and terminal device for electronic component |
CN102484957A (en) * | 2011-06-14 | 2012-05-30 | 华为终端有限公司 | Device with heat insulation structure |
WO2011150874A3 (en) * | 2011-06-14 | 2012-05-10 | 华为终端有限公司 | Device with heat insulation structure |
US20150022976A1 (en) * | 2011-11-08 | 2015-01-22 | Robert Bosch Gmbh | Electronic Module for a Control Unit |
US9763344B2 (en) * | 2011-11-08 | 2017-09-12 | Robert Bosch Gmbh | Electronic module for a control unit |
US20140347819A1 (en) * | 2011-12-21 | 2014-11-27 | Robert Bosch Gmbh | Electronics Module for a Vehicle |
CN104620454A (en) * | 2012-09-11 | 2015-05-13 | 株式会社自动网络技术研究所 | Electrical connection box |
EP2879256A4 (en) * | 2012-09-11 | 2015-09-23 | Autonetworks Technologies Ltd | Electrical connection box |
US9402324B2 (en) | 2012-09-11 | 2016-07-26 | Autonetworks Technologies, Ltd. | Electrical junction box |
WO2014111313A1 (en) * | 2013-01-17 | 2014-07-24 | Continental Automotive Gmbh | Device for receiving electronic components |
US20150210155A1 (en) * | 2014-01-29 | 2015-07-30 | Dr. Ing. H.C. F. Porsche Aktiengesellschaft | Cooling device for a hybrid module of a hybrid vehicle |
US9636994B2 (en) * | 2014-01-29 | 2017-05-02 | Dr. Ing. H.C.F. Porsche Aktiengesellschaft | Cooling device for a hybrid module of a hybrid vehicle |
US20170290178A1 (en) * | 2014-09-03 | 2017-10-05 | Conti Temic Microelectronic Gmbh | Control Unit Device For A Motor Vehicle And Method For Manufacturing Such A Device |
US10188005B2 (en) * | 2014-09-03 | 2019-01-22 | Conti Temic Microelectronic Gmbh | Control unit device for a motor vehicle and method for manufacturing such a device |
US10424947B2 (en) | 2017-02-13 | 2019-09-24 | Yazaki Corporation | Battery monitoring device |
CN114128051A (en) * | 2019-07-19 | 2022-03-01 | 浩亭电子有限公司 | Contact element for electrically connecting circuit boards and method for assembling a circuit board assembly |
US11799218B2 (en) | 2019-07-19 | 2023-10-24 | HARTING Electronics GmbH | Contact element for electrically connecting printed circuit boards and method for assembling a printed circuit board arrangement |
US20220360915A1 (en) * | 2021-05-04 | 2022-11-10 | Sivantos Pte. Ltd. | Charging device of a hearing aid and system with the charging device |
Also Published As
Publication number | Publication date |
---|---|
US6442027B2 (en) | 2002-08-27 |
DE10107711A1 (en) | 2001-08-30 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US6442027B2 (en) | Electronic control unit having connector positioned between two circuit substrates | |
US6466447B2 (en) | Electronic control unit having flexible wires connecting connector to circuit board | |
US6572412B2 (en) | Control device and soldering method | |
JP3864873B2 (en) | Electronic control unit | |
JP6227937B2 (en) | Electronic control device for vehicle | |
JP4851154B2 (en) | Circuit board built-in housing | |
JP2005080354A (en) | Circuit configuration | |
JPH113754A (en) | Method for adaptive electrical connection between adjacent circuits | |
US20020186551A1 (en) | Electronic control unit having flexible wires connecting connector to circuit board | |
JP2021005580A (en) | Electronic control device | |
JPH10208798A (en) | Substrate connection device and actuator installation unit using the same | |
JPH09199841A (en) | Printed-wiring board | |
JP2017208273A (en) | Electronic device | |
JP4462174B2 (en) | Electronic circuit equipment | |
JP2001267022A (en) | Electronic controller | |
WO2021075360A1 (en) | Electronic control device | |
JP2671700B2 (en) | Electrical equipment | |
JP4124528B2 (en) | Electronic control unit | |
JP2010199431A (en) | Electronic module | |
JP4107930B2 (en) | Press-fit bonded wiring board and electronic equipment | |
JP2001359223A (en) | Electronic control unit | |
JP2002009414A (en) | Electrical mechanical connection device between power source module and printed circuit board | |
JP2004056022A (en) | Electronic control substrate | |
JP2007234675A (en) | Electronic apparatus | |
US20110230062A1 (en) | Electronic apparatus |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: DENSO CORPORATION, JAPAN Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:SANADA, KAZUYA;YAGURA, TOSHIAKI;REEL/FRAME:011393/0026 Effective date: 20001211 |
|
FEPP | Fee payment procedure |
Free format text: PAYOR NUMBER ASSIGNED (ORIGINAL EVENT CODE: ASPN); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY |
|
FPAY | Fee payment |
Year of fee payment: 4 |
|
FPAY | Fee payment |
Year of fee payment: 8 |
|
REMI | Maintenance fee reminder mailed | ||
LAPS | Lapse for failure to pay maintenance fees | ||
STCH | Information on status: patent discontinuation |
Free format text: PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362 |
|
FP | Lapsed due to failure to pay maintenance fee |
Effective date: 20140827 |