US 1664612 A
Abstract available in
Claims available in
Description (OCR text may contain errors)
April 3, 1928.
L. O. FRENCH FUEL CONTROL VALVE Filed Nov. 4, 1925 INVEN TOR.
Patented Apr. 3, 1928.
UNITED STATES LOUIS O. FRENCH, OF MILWAUKEE, WISCONSIN.
Application filed November 4, 1925. Serial No. 66,769.
The invention relates to electromagnetically-operated valves, and more particularly to an electromagnetic valve suitable for use in the fuel-feeding or fuel-injection systems of internal combustion engines, to control the amount of fuel supplied to the engine.
It has heretofore been proposed to use solenoid or plunger type electromagnets for operating valves for various purposes, and 1t has also been proposed to use an electromagnet with an exposed coil adjacent a large armature associated with a. fuel injection valve, but I have found that such prior devices are not suited to meet the speed requirements of high speed internal combustion engines, such as automotive and aeronautical type engines. Thus one object of the invention is to provide an electromagnetically-operated valve which is suited for operation at high speeds in which the electromagnet is so constructed as to operate with good efliciency on a very light-weight control valve of small displacement area working in a chamber containing the fuel,
To obtain efficient operation at high speeds the air gap between the electromagnet and the armature shouldbe very small and should be readily maintained, and it is another obj ect of this invention to provide a construct- 0 tion in which the adjustment of the valve,
when such is necessary, may be readily accomplished without the-use of special measuring instruments and by relatively unskilled mechanics or other persons.
A further object of the invention is to provide an electromagnetically-operated valve associated with a fuel-injection valve designed to operate at high speed in substantial synchronism with the electromagneticallyoperated valve.
The invention further consists in the several features hereinafter set forth and more particularly defined by claims at the conclusion hereof.
In the drawings, Fig. 1 is a vertical sectional view of an electromagnetically-operated valve embodying the invention;
Fig. 2 is a detail sectional View through the valve unit;
Fig. 3 is a view similar to Fig. 1, with certain modifications;
Fig. 4 is a diagrammatic view of a circuit arrangement for one type of fuel injection system in which the control valve may be 55 used.
In Fig 1 the numeral 5 designates a cas ing member, 6 the control valve, 7 the valve seat member having an opening 8 therein, 9 a seat-clamping member, 10 the electromagnet, and 11 the valve-closing spring.
The casing member 5, of non-magnetic material, has a flat top 12, a recess 13, a valveguide bore 14, bores 15 and 16, an annular flange or flange portions 17 below its top, and a reduced threaded end 18, here shown as fitting within a threaded opening in the cylinder or cylinder-head 18 of an internal combustion engine, and a passage 19.
The control valve, shown in detail in Fig. 2, includes a needle-valve 20 and the armature 21, which may be in one piece but I prefer to make the armature of soft iron or soft steel and the valve of hard steel. The armature is formed as a disk and has a tubular rivet 22 of brass or other non-magnetic material secured within its central opening and overlapping the edges thereof, the upper flanged edge 23 of said rivet extending into a recess 24 in said disk and slightly above the top face thereof to prevent direct engagement of the magnet and disk and thus prevent freezing. The rivet 22 has a pressed fit on the reduced upper end 20 of the stem of the valve, but said valve may be readily driven out of said rivet for replacement. The valve either has a passage 25 in it, from its upper end to a point below the armature, or the part projecting above the armature has transverse grooves 25' therein and the armature may have one or more holes 26 in it for ready passage or displacement of fuel from one side of the valve to the other, Furthermore, these holes 26 reduce the displacement area of the armature and thus aid high speed operation.
The electromagnet 10 comprises a centrally disposed soft iron or soft steel core 27 having a flange 28 of similar material integral therewith or welded thereto and a reduced end portion 29 providing a shoulder 30. A disk 81 of non-magnetic material fits over the end portion 29 and against the shoulder 30. These parts form a bobbin on which the coil 32 is wound and from which it is suitably insulated. A cylindrical shell 33 of magnetic material surrounds the coil and has a contacting fit at its upper end with the outer edge of the flange 28, and preferably extends beyond the core at its other end and is provided with an annular flange or outwardly projecting flange portions 34-. An annular disk 35 of magnetic material fits in a bore 36 at the lower end of the shell against a shoulder 36' and is secured thereto by a tight pressed [it or by welding, or may be formed integral with the shell 33. That portion of the shell 33 which surrounds the coil need not be solid throughout as its prin cipal function is to provide a return circuit. The magnet thus formed is an iron-clad magnet having an inner pole formed by the end portion 29 of the core 27 and an outer pole formed by the disk 35, and a filler 37 of non-magnetic metal composition fills the space between the poles in a fluid-tight manner.
F or high speed operation the disk 35 extends inwardly to within a very short dis tance from the end 29 of the core and as shown the inner edge of this disk extends within the projected area of the main body of the core to reduce the gap between the poles to a short distance. Thus the flange 28, shell 33 and disk 35 form a good path for the magnetic flux and substantially the only gap is that provided by the space containing the filler 37. The fixed disk 35, extending as it does to within a short distance of the inner pole core, is important to the successful working of the device at high speeds, as it enables one to use an armature whose area is only slightly greater than the lower end of the core, as the outer edge of said armature extends a short distance beyond the central opening of said disk. This arrangement materially reduces the weight of the valve unit and its displacement volume and/or area is small compared to those valve structures in which the armature of the valve is of an area equal to the entire face of the magnet. Thus the small weight and displacement volume and/or area of the valve reduces its inertia and its resistance to movement through the liquid in which it works and permits of high speeds coupled with the fact that without the iron magnetic return circuit the electromagnet itself would not be eflicient enough to' properly actuate the valve, since with high speeds the spring 11 must be relatively strong to provide for a quick release and rapid closing action.
The spring 11 hearing on the top of the valve extends up into a bore 38 and seats at its upper end on the head of a tensionadjusting screw 39 adjustably mounted in a threaded bore 10 in the core and provided with a passage 11 connecting the bore 38 with a tapped hole 4-2 for the fuel supply pipe. It will, of course, be understood that where the valve works in a pressure chamber, as here shown, the pressure of the fuel also acts to close the valve.
The pole face of the magnet 10 and the casing member 5 are secured together to form the housing for the valve As shown, this connection is made between the outer shell of the magnet and the member 5 by screws 4-3 passing through the flange 34 and into the flange 17, and a gasket 44 of metal, or other suitable material, is interposed between the flat face 12 of the member 5 and the disk 35 A plurality of very thin metal *ashers or shims 45 are mounted in the bore 16 between the plate 7 and the shoulder formed between the bores 15 and 16. These washers are provided so as to maintain the upper face of the armature proper on a level with the face 12 of the member 5 so that the clearance or air gap distance between said armature and the magnet is determined by the gasket 14 which when clamped between the casing and magnet is of a thickness to provide the proper working air gap. For ease of assembly in manufacture, and in case it becomes necessary to grind the valve, or the valve or its seat wears down to such an. extent as to increase the air gap, then a removal of one or more of the w( shers 45 so as to bring the armature again level or flush with. the face 12 upon the reclamping of the plate 7 against the remaining shims again establishes the proper air gap distance deter mined by the gasket 14-. Thus, the leveling of the disk 21 with the top of the casing by the adjustment of the washers may be read ily accomplished by a straight edge and without the use of special measuring tools, even though the working clearance or air gap distance is extremely small, as, for instance, two or three thousandths of an inch, the thickness of the gasket, and each washer being a thousandth of an inch in thickness. Thus, the flat face of the casing and the gasket form a clearance-determining means. Furtheremore, in case of excessive wear the valve 20 and the seat member 7 may be readily and cheaply replaced.
lVith this construction, the fuel introduced under pressure, by a suit-able pumping sys tem, to the opening 42 passes down through passage 41, here 38, through the passage 25 or around the armature to the valve chamber including the recess 13 and thence through the passage 19 to the space formed by the bores 15 and 16, and when the magnet 10 is energized the valve 20 is lifted and the fuel discharged through the nozzle 8 and a passage a6 in the member 9 into the cylinder of the engine when such valve is used as a fuel injector, and as the lift of the valve is very small very small quantities of fuel may be readily supplied to the engine.
The electromagnetically-operated control valve shown in Fig. 3 is generally similar to that previously described, the valve unit it self being identical and the electromagnet being similar except that the disk 35 is shown as integral with the shell 33 which lUU is secured to the casing member 5 by a threaded connection 47 so that the lower end only of the magnet and the casing 5 form a housing for the valve. The parts 11, 15, 16, 19, 27, 28, 29, 31, 32, 33, 37 and are similar to the parts 11, 15, 16, 19, 27, 28, 29, 31, 32, 33, 37 and 45, previously described, and are similarly disposed. The top of the member 5 has an annular curved edge 48 abutting the disk 35 and cooperating with a recessed portion 49 of said disk to provide a clearance-determining means, the shims or washers 45 being used to bring the top face of the armature of the valve to a level with the top of the curved edge 48 for the pur pose previously described in connection with the shims 45.
In this construction the valve 20 seats over a short passage 50 in a plate or member 51 which is clamped to the casing in a fluidtight manner by the threaded upper end of the injector valve casing 52 engaging a flanged portion 53 of said member 51 and mounted in the threaded bore 54 of said casing 5. The casing 5 has a tapped opening 55 for connection with a. fuel supply pipe, not shown, by which the fuel under pressure is delivered to the valve housing, and when the electromagnet is energized to lift the valve 6, the fuel is free to pass through the opening 50.
In Fig. 3 the injector proper comprises the casing 52, a nozzle plate 56 having a nozzle opening 56 and detachably secured to casing 52 by an internally flanged nut 57, a check valve 58 working in a bore 59 in said casing, and a spring 60 interposed between agrooved flange 61 of said valve and the lower end of the bore 59.
The check valve 58 is a needle valve seat ing against the opposite end of the very short passage 50 from that of the valve 6, and is of relatively light weight. The length of the passage between these two valves is short and of uniform diameter so that the opening of the valve 6 is immediately followed by the opening of the valve 58. To permit of high speeds this valve 58 is limited in its movement by having its stem engage with the plate 56, said stem at its lower end working in a reduced bore 62 of the casing 52 and having a fuel passage 63 alined with the passage 56 and communieating by transverse passages 64 with the bore 59. Thus, when the coil 32' is energized and the valve 6 is lifted, the fuel passing through the passage 50 exerts pressure on and unseats the valve 58 and thence passes by way of passages 59, 64 and 63 to and through the opening 56 into the cylinder of the engine, the injector casing being shown as having a threaded connection with the cylinder head 65 of the engine.
As an illustration of one system in which the valve may be used, I show, in Fig. 4, a
circuit arrangement wherein one side of a battery 66, or other suitable source of elec trical energy, is connected by a conductor 67, including a resistance 68, to one terminal of the electromagnet, the other terminal 69 being grounded. The other side of the battery 66 is connected by a conductor 66 to the fixed contact 70 of a switch mechanism, including a pivoted contact 71 which is grounded. This pivoted contact 71 is spring-pressed against and acted upon by a cam 72 driven by the engine to open and close the circuit at and for the desired periods of time so that the electromagnetically-operatcd valve will be opened at and for varying periods of time and thus control the time and amount of fuel furnished to the engine. Any suitable switch construction may be used but for one type of switch mechanism suitable for this purpose, reference is had to my copending application Serial No. 712,830, filed May 12, 1924.
lVith the construction above described it is possible to provide a very small lightweight valve 6 as, for instance, one weighing not more than one-half ounce, and by having this valve acted upon by a relatively heavy spring as, for instance, ten or twelve pounds, an extremely quick action is given to the valve so that it may be used on engines whose speed exceeds seventeen hundred revolutions per minute. The resistance 68 in the circuit also insures a quick response of the electromagnet as it reduces the time constant of the magnetic circuit.
\Vhile the device has been shown as an injector valve, or one associated with a fuel injection valve, it maybe used as acontrol valve in fuel injection systems of my copending applications, Serial No. 660,840, filed September 4, 1923, Serial No. 712,830, filed May 12, 1924, and Serial No. 1,328, filed January 8, 1925.
What I claim as my invention is:
1. In an electromagnetically-operated control valve mechanism, the combination of a valve casing member, an iron-clad electromagnet having a fluid-tight pole face cooperating with said member to form a fluidcontaining valve housing and including a central pole and an outer pole extending inwardly to within a short distance from said central pole, and a needle control. valve biased to closed position and mounted in said housing and having an armature cooperating with said poles and overlying for a short distance that portion of the outer pole closest to said central pole.
2. In an electromagnetically-operated con trol valve mechanism, the combination with the electromagnet, of a control valve structure including a needle-valve, a sleeve of non-magnetic material secured to the stem of said valve, an armature secured to said sleeve and cooperating with said electromagnet, said sleeve projecting slightly beyond said armature and toward said electromagnet.
3. In an electromagnetically-operated control valve mechanism, the combination with the electromagnet, of a casing member detachably secured thereto, a valve working within said casing member and having an armature cooperating with said electromagnet. clearance-determining means including a levelling surface on said casing member, a valve seat member secured to said casing, and adjustable means for bringing the top face of the armature substantially flush with said levelling surface on said casing member.
4:. In an electromagnetically-operated control valve mechanism, the combination with the electromagnet, of a casing member detachably secured thereto, a valve working within said casing member and having an armature cooperating with said electromagnet, clearance-determining means including a levelling surface on said casing member, a valve seat member secured to said casing, and means including a plurality of washers for adjusting said seat member to bring the top face of the armature substantially flush with said levelling surface on said casing member.
5. In a fuel-feeding system, the combination of an electromagnet, a spring-closed con trol valve actuated by said electromagnet, a valve seat member having a short passage over one end of which said control valve is seated, and a spring-closed, outwardly-opening fuel injection needle valve seating over the other end of said passage.
6. In a fuel-feeding system, the combination of an electromagnet, a spring-closed control valve actuated by said electromagnet, a valve seat member having a short passage over one end of which said control valve is seated, a spring-closed, outwardlyopening fuel injection needle valve seating over the other end of said passage and controlling the passage of fuel to the engine, and means forlimiting the movement of said fuel injection valve.
7. In a fuel-feeding system, the combination of an electromagnet, a casing member detachably secured thereto and cooperating therewith to form a fuel-containing valve housing, a spring-closed control valve working in said housing and actuated by said electromagnet, a valve seat member having a passage over one end of which said control valve is seated, a fuel injection casing securing said seat member to said casing member, and a spring-closed, outwardly-opening needle valve in said fuel injection casing seating over the other end of said passage, said fuel injection casing having a discharge nozzle.
8. In an electromagnetically-operated control valve mechanism, the combination of a valve casing member, an iron-clad electromagnet detachably secured to said member and having a fluid-tight pole face cooperating therewith to form a fluid-containing valve housing, said pole face including a central pole, an annular outer pole surrounding said central pole having its inner edge projecting toward and spaced a short distance from said central pole and a filler of non-magnetic material between said poles, and a spring-closed needle type valve mounted in said housing and having an armature cooperating with said poles and overlying the inner edge of said outer pole for a short distance.
9. In an electromagnetically-operated control valve, the combination of a valve casing member, an ironclad electromagnet having a fluid-tight pole face cooperating with said member to form a fluid-containing valve housing, said electromagnet including a central core having a flanged outer end, an annular pole member surrounding the inner pole face end of said core and spaced a short distance therefrom, a metal shell secured to said annular pole member and to said flanged outer end of said core, an energizing coil within said shell and surrounding said core, and a filler of non-magnetic material between said poles, and a spring-closed control valve mounted in said housing and having an armature. cooperating with said poles and terminating slightly beyond the inner edge of said outer pole.
10. In an electromagnetically-operated control valve mechanism, the combination of an ironclad electromagnet having a central core provided with a pole portion of less area than the area of said core and forming an inner pole and having an outer pole surrounding said inner pole and spaced therefrom but with its inner edge lying within the projected area of the main part of the core, a casing means associated with said poles and forming a valve housing, and a control valve mounted in said housing and having an armature cooperating with said poles.
11. In an electromagnetically-operated control valve mechanism, the combination of a valve casing member, an ironclad electromagnet having a fluid-tight pole face cooperating with said. member to form a fluid containing valve housing and including a. core provided with a pole portion of less area than the area of said core and forming an inner pole and an outer pole surrounding said inner pole and spaced therefrom a short distance but with its inner edge lying within the projected area of the main part of the core, and a control valve mounted in said housing and having an armature cooperating with said poles and overlying for a short distance that portion of the outer pole closest to said inner pole.
12. In an electromagneticallyoperated control valve mechanism, the combination of an electromagnet provided with a pole face having a clearance-determining recess, a casing member secured to said magnet and having a levelling surface adjacent said recess, a valve working within said casing member and having an armature cooperating with said electromagnet, and means for adjusting the valve to bring the top face of the armature substantially flush with said levelling surface on said casing member.
13. In an electromagnetically operated control valve mechanism, the combination of an iron-clad electromagnet having a central bore provided with a pole portion of less area than the area of said core and forming an inner pole and having an outer pole surounding said inner pole and spaced therefrom but with its inner edge defining an area not materially greater than the main part of the core, a casing means associated with said poles and forming a valve housing, and a control valve mounted in said housing and having an armature cooperating with said poles.
14. In an electromagneticallyoperated control valve mechanism, the combination of an electromagnet provided with a pole face, a casing member secured to said magnet and having a levelling surface adjacent said pole face, a valve working Within said casing and having an armature cooperating with said electromagnet, and means for adjusting the valve to bring one face of the armature substantially in line with the levelling surface on said casing member.
In testimony whereof, I affix my signature.
LOUIS O. FRENCH.