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Publication numberUS3722851 A
Publication typeGrant
Publication dateMar 27, 1973
Filing dateJul 9, 1971
Priority dateMay 5, 1969
Publication numberUS 3722851 A, US 3722851A, US-A-3722851, US3722851 A, US3722851A
InventorsLove A
Original AssigneeBrown H Co
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Timing valves
US 3722851 A
Images(4)
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Description  (OCR text may contain errors)

United States Patent 91 Love 1 Mar. 27, 1973 [73] Assignee: Harold Brown Company, Houston,

Tex.

[52] U.S. Cl. ..251/54, 251/49, l37/624.14 [51] Int. Cl ..Fl6k 31/12 [58] Field of Search ..137/624.11, 624.14, 624.15; 251/54, 49, 20

[56] References Cited UNITED STATES PATENTS 3/1930 Forsberg ..251/54X 11/1965 Trenor ..251/54 FOREIGN PATENTS OR APPLICATIONS 536,852 10/1931 Germany ..251/54 Primary Examiner-Alan Cohan Attorney-Michael P. Breston [57] ABSTRACT This invention relates to timing valves for controlling the pressure fluid between a supply line and a utilization line servicing one or more pressure utilization devices with pressure signals of adjustable duration and frequency. The operation of a pair of complementary timing valves in connection with a controller is synchronized by the pressure signals applied to the utilization line. One timing valve begins its predetermined delay period on the application of the pressure signal, while the other timing valve begins its delay period on the termination of the pressure signal. Each timing valve includes a time-calibrated variable orifice forming part of a timing chamber which includes fluid which is placed under pressure by a flexible diaphragm. A master control valve coupling the supply line to the utilization line can be controlled by the timing valves and the successive displacements of the diaphragms.

8 Claims, 5 Drawing Figures Patented March 27, 1973 3,722,851

4 Sheets-Sheet 2 Addison N. Love INVENTOR ATTORNEY Patented March 27, 1973 4 Sheets-Sheet 5 Addison N Love INVENTOR BY %'r;m/ c

FIG.3

ATTORNEY Patented March 27, 1973 3,722,851

4 Sheets-Sheet 4 Ada/son N, Love IN VEN TOR A T TORNEY TIMING VALVES CROSS-REFERENCE TO RELATED APPLICATION This application is a division of application Ser. No. 821,745, filed May 5, 1969 and now U.S. Pat. No. 3,653,393 issued Apr.4, 1972.

BACKGROUND OF THE INVENTION Pressure fluid utilization devices such as valves, mo-

tors, pneumatically-operated fog horns, etc., are typically operated or controlled by fluid controllers providing pressure fluid signals having time adjustable ON and OFF intervals. Such controllers for extracting from a supply source pressure signals are well known, Typically they employ timing mechanisms which are recycled by solenoids or fluid-controlled valves. Thus, an independent source of either electric power or pressure fluid must be provided to operate such controllers.

In some installations the lack of electricity, while in others a serious safety hazard, make the utilization of solenoid-controlled timing mechanisms undesirable. While fluid-controlled timing mechanisms are preferred for such installations, in the past they have required independent pressure fluid control sources. When the same supply pressure fluid source was used both to provide the desired intermittent pressure signals and to control the timing mechanisms, it was found that the operating life and the reliability of such time mechanisms were rather poor. Another frequent problem encountered with such time mechanisms was the relative difficulty to accurately control and/or maintain the duration and/or the frequency of the pressure signals.

It is, therefore, a main object of this invention to provide new and improved fluid-operated timing valves which overcome the above-mentioned and other shortcomings of prior art timing mechanisms.

SUMMARY OF THE INVENTION Improved fluid-operated timing valves are provided for controlling pressure fluid'between a supply line and a utilization line. A pair of such timing valves acting in a complementary manner are employed for a controller including a master control valve. The timing interval of one timing valve is initiated at the start of the pressure signal, while the timing interval in the complementary valve is initiated at the end of the pressure signal. The valve spool in the master control valve is responsive to the resultant effect of the pressures in two pressure fluid lines. The pressure in each line is controlled by a timing valve.

Each of the pair of complementary timing valves includes a housing defining a timing chamber and a recirculating chamber separated from each other by a flexible diaphragm. A timing spring, when unrestrained, urges the diaphragm to compress the fluid in the timing chamber. A time-calibrated variable orifice provides an outlet for the pressure fluid from the timing chamber to the re-circulating chamber. A control rod is coupled to the diaphragm and is movable therewith. Fluid-operated means are coupled to the rod to periodically restrain the rod and hence the diaphragm.

In one timing valve the rod is restrained at the start and in the other valve the rod is restrained at the end of the pressure signal in the utilization line. By using a pair of such complementary, fluid-operated, diaphragmcontrolled timing valves, a fluid-operated utilization device can be provided with pressure signals of independently-adjustable duration and frequency.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings illustrate preferred timing valves for pressure fluid controllers in accordance with this invention and wherein:

FIG. 1 is a more-or-less diagrammatic view of a pressure fluid controller employing the timing valves of this invention, the controller being in one of its control positions when the pressure signal is OFF;

FIG. 2 shows the position of the controller immediately prior to the leading edge of the pressure signal;

FIG. 3 shows the position of the controller when the pressure signal is ON;

FIG. 4 shows the position of the controller immediately prior to the trailing edge of the pressure signal; and

FIG. 5 is a pressure-time diagram illustrating the operation of the system shown in FIG. 1.

To better understand the operation of the timing valves of this invention, they will be described in connection with a fluid control system which is claimed in said copending application.

Referring now more particularly to the accompanying drawings, wherein like reference characters are applied to like parts throughout the views, there is shown a fluid controller, generally designated as 10, contained in a housing 11. Controller 10 is adapted to continuously receive at an inlet port 12 pressure fluid and to periodically supply to an outlet port 14 pressure signals of adjustable duration and frequency. Inlet port 12 is connected to an inlet line 16, and outlet port 14 is connected to a utilization or signal line 18. Fluid communication between inlet line 16 and signal line 18 is governed by a master control valve, generally designated as 20. Valve 20 defines a passageway 22 which is either open or closed depending on the position of its spool valve 24 in a bore 25. Bore 25 is in fluid communication with two axially-opposed control ports 27, 29 in the body 31 of valve 20.

To control the displacement of a movable element such as spool 24, there are provided, in accordance with this invention, two fluid-operated timing valves. One timing valve, generally designated as 26, is actuated by pressure fluid in a branch line 30. The other timing valve, generally designated as 28, is actuated by pressure fluid in a branch line 32. Both branch lines 30, 32 and signal line 18 are connected to a main line 34 which receives pressure fluid from the master valve 20 when passageway 22 is open.

The displacement of spool 24 in bore 25 is controlled by the combined effect of pressure fluid in lines 40 and 42, respectively coupled to control ports 27 and 29. Inlet line 16 is connected to line 40 through a pilot valve 44 and to line 42 through a pilot valve 44'.

Timing valve 28 provides a timed-delay interval D, on the application of pressure fluid through line 32, whereas timing valve 26 provides a timed-delay interval D, on the removal of pressure fluid from line 30. At the end of interval D,, the pressure in line 40 is reduced causing the upper (as shown in the drawings) displacement of spool 24. At the end of interval D,, the pressure in line 42 is reduced, thereby allowing spool 24 to move downwardly. When both lines 40 and 42 are under substantially equal pressure, the acting forces on spool 24 are balanced and spool 24 remains in the same position it assumed prior to the time when both lines 40 and 42 were under equal pressure. When spool 24 is in its upper position, fluid passageway 22 is open to allow fluid pressure communication between inlet line 16 and main line 34.

The timing valves 26 and 28 of this invention will now be described in greater detail. Valve 26 will hereinafter be referred to as the cycle timer" since it controls the OFF-time of the pressure signal, and valve 28 will hereinafter be referred to as the signal timer since it controls the ON-time of the signal. Cycle timer 26 controls the displacement of a valve element 50, schematically represented by a triangle, in pilot valve 44. Valve element 50 is connected to an elongated stem 52 which extends outwardly of housing 54 of timer 26. Housing 54 defines a timing chamber 56, a recycling chamber 58, and includes a partition wall 60 having an upper face 62 and a lower face 64. Separating the timing chamber 56 from the recycling chamber 58 is a flexible diaphragm 66. The fluid from timing chamber 56 is allowed to vent out into the recycling chamber 58 through a time-calibrated orifice schematically represented as 68 contained in one or more dials (not shown). Fluid is allowed to enter the timing chamber 56 from the recycling chamber 58 through a suitable check valve 70.

The timing mechanism portion of timer 26, which includes: the diaphragm, the timing and recycling chambers, the calibrated orifice and the check valve, forms no part of this invention and can be purchased commercially. One such timing device offers nine discrete ranges from 0.2 seconds to 60 minutes, adjustable by means of time-calibrated dials which control the opening of orifice 68.

A brief description of the operation of such a conventional diaphragm-operated timing mechanism will now be given. A spring 69 is positioned between a center head 72, in the center of diaphragm 66, and the upper face 62 of wall 60. At the start of the timed interval D diaphragm 66 is pulled downwardly toward wall 60, thereby allowing fluid to enter timing chamber 56 through check valve 70. Spring 69 exerts an inward force on diaphragm 66 thereby compressing the fluid in timing chamber 56. The fluid is allowed to vent out from timing chamber 56 to the recycle chamber 58 at a rate depending on the time-calibrated opening of orifree 68.

In accordance with this invention, to the center head 72 is secured a control rod 74 which extends outwardly through an opening 77 in end wall 76 of housing 54. Between the lower face 64 of partition wall 60 and end wall 76 is provided a double-diameter cylinder 80. Cylinder 80 slidably receives a double-diameter piston 82 having an upper O-ring 84 and a lower -ring 86. Between O-rings 84 and 86 is defined a fluid-tight control chamber 88 which communicates with line 30. Piston 82 has an axial bore 90 which extends from its upper face 92 to its lower face 94. Face 94 is the bottom face of a control finger 96 which may be an integral part of the body of piston 82, as shown in crosssection. Piston 82 includes a downwardly-directed, cylindrical opening 100 housing a piston bias spring 102 resting against end wall 76 and against the bottom wall 104 in the cylindrical opening 100. Spring 102 normally urges piston 82 upwardly, whereas pressure fluid in chamber 88 urges piston 82 downwardly against the force of spring 102.

Coupled to the free end of actuating rod 74 is an actuation mechanism generally designated as 106, which, in its simplest form, may include a horizontal (as shown in the drawings) lever arm 108 having a sufficient length so that it can lift stem 52 when the actuating rod 74 is in its raised position. Movement of stem 52 unseats the pilot valve element 50 of the three-way pilot valve 44, thereby discontinuing or throttling down the pressure fluid communication between inlet line 16 and control line 40, while at the same time allowing the pressure in line 40 to exhaust through vent 107 around stem 52.

The signal timer 28 is in all respects similar to the cycle timer 26 except that in timer 28 the doublediameter piston is inverted, and the force exerted by the piston bias spring is in an opposite direction. Therefore, to facilitate the understanding of the timers 26 and 28, like reference characters, added with a prime, have been applied to like parts in timer 28. The difference in the operation of timer 28 from that of timer 26 will become apparent from the description of the operation which follows. For the sake of completeness, and not forming part of this invention, normally connected to the input 12 of controller 10 is a pressure fluid source supplying pressure fluid to input line 16 via suitable valves 122 and 124. To the output 14 of controller 10 is connected a suitable utilization device such as a motor valve 126.

DESCRIPTION OF OPERATION In FIG. 5 an arbitrary initial time instance was selected and designated as T The condition of controller 10 at time T is shown in FIG. 1. Spool 24 is then at its lowermost position. Finger 96 is raised to allow spring 69 to initiate the time interval D Finger 96 is at its lowermost position to prevent spring 69' from exerting a force against diaphragm 66'. As a result, lever 108 is disengaged from stem 52 and lever 108' is disengaged from stem 52. Fluid communication between inlet line 16 and control lines 40 and 42 is established through the three-way pilot valves 44 and 44'. Since the same pressure fluid is in both lines 40, 42, spool 24 is not subjected to an unbalanced force and remains in its lowermost position thereby closing the fluid passageway 22 between inlet line 16 and main line 34.

Depending on the time set on the dial of the variable orifice 68, fluid from timing chamber 56 is allowed to vent out into the recycling chamber 58. The transfer of fluid from timing chamber 56 allows the diaphragm 66 to move inwardly and the actuating rod 74 to move upwardly.

At time T D,, diaphragm 66 has traveled from its extended position to its relaxed position, as shown in FIG. 2. Since operating rod 74 also traveled with diaphragm 66, lever arm 108 will engage stem 52 causing pilot valve element 50 to become unseated, thereby reducing pressure fluid communication between lines 16 and 40 and allowing the pressure fluid in line 40 to escape through vent 107. A reduction in pressure in line 40 causes an upward force to become exerted on spool 24 by the pressure fluid in line 42. At time T spool 24 will have shifted from its lowermost position to its uppermost position as shown in FIG. 3. The direction of the acting forces on the various parts are shown throughout the drawings by arrows.

When spool 24 is in its uppermost position, fluid communication is established between line 16 and main line 34 through the passageway 22 in the master control valve 20. As soon as pressure fluid is established in line 34, it is communicated through branch lines 30, 32 to the actuating chambers 88, 88, respectively. As a result, piston 82 moves downwardly and piston 82' moves upwardly.

Of course, pressure fluid in main line 34 provides pressure fluid to outlet 14 and hence to utilization device 126. Thus, at time T starts the leading edge of the pressure signal or pulse, subsequent to time interval D provided by cycle timer 26.

Since finger 96' is in its uppermost position, timing spring 69' is no longer restrained and is allowed to exert a force against the fluid in timing chamber 56'. Just as with cycle timer 26, the operating rod 74' moves upwardly until lever 108 is allowed to engage the stem 52. The lifting of the pilot valve element 50' produces at time T a reduction in the pressure in line 42 and the ensuing downward displacement of spool 24 at time T thereby marking the trailing edge of the pressure signal or pulse 130.

The position of the controller thereafter is the same as shown in FIG. 1. The controller 10 is ready to start its operating cycle all over again.

The entrapped fluids in master control valve are vented through vent 132. As will be seen from FIG. 5, time interval D T, and time interval D T; T

What I claim is:

l. A timing valve comprising in combination:

a housing defining a timing chamber, a recycling chamber, and a flexible diaphragm separating said timing chamber from said recycling chamber;

a timing spring exerting a force against said diaphragm to compress the fluid in said timing chamber;

a time-adjustable orifice providing an outlet for the fluid from said timing chamber to said recycling chamber;

a control rod fixedly attached to and movable in unison with said diaphragm;

a pilot valve including a valve element for controlling the fluid flow through said pilot valve;

actuating means, including a fluid actuatable member responsive to fluid pressure, said member being detached from said timing spring and being coupled between said rod and said pilot valve element to control said pilot valve in dependence upon the setting of said orifice.

2. A timing valve comprising in combination:

a housing defining a timing chamber, a recycling chamber, a partition wall having an upper face and a lower face, and a flexible diaphragm separating said timing chamber from said recycling chamber;

a distinct timing spring between said upper face and said diaphragm,

said spring when unrestrained urging said diaphragm away from said upper face to compress the fluid in said timing chamber;

a time-adjustable orifice providing an outlet for the fluid from said timing chamber to said recycling chamber;

a control rod fixedly attached to and movable in unison with said diaphragm;

fluid actuatable means including a cylinder,

a piston slidably mounted in said cylinder and being detached from said timing spring, and

means applying pressure fluid to said piston to cause the piston to move in response thereto;

a pilot valve including a valve element for controlling the fluid flow through said pilot valve; and

an actuation mechanism coupled to said pilot valve element and to said control rod and being responsive to said fluid actuatable means to control said pilot valve element in dependence upon the setting of said orifice.

3. The timing valve of claim 2 and further including:

a distinct piston-bias spring coupled to said piston to normally urge said piston to one position; and

said applied pressure fluid urging said piston to another position against the force exerted by said piston bias spring.

4. A timing valve comprising in combination:

a housing defining a timing chamber, a recycling chamber, a partition wall having an upper face and a lower face, and a flexible diaphragm separating said timing chamber from said recycling chamber;

a timing spring between said upper face and said diaphragm, said spring when unrestrained urging said diaphragm away from said upper face to compress the fluid in said timing chamber;

a time-adjustable orifice providing an outlet for the fluid from said timing chamber to said recycling chamber;

a control rod attached to and movable with said diaphragm;

fluid actuatable means including a cylinder, a piston slidably mounted in said cylinder, said piston defining a center bore, said control rod being freely movable in said bore, and means applying pressure fluid to said piston;

a pilot valve including a valve element for controlling the fluid flow through said pilot valve;

an actuation mechanism coupled to said pilot valve element and to said control rod and being responsive to said fluid actuatable means to control said pilot valve element in dependence upon the setting of said orifice;

a piston bias spring coupled to said piston to normally urge said piston to one position; and

said applied pressure fluid urging said piston to another position against the force exerted by said piston bias spring.

5. The timing valve of claim 4 wherein said piston is a double-diameter piston.

6. The timing valve of claim 4 wherein said pilot valve is a 3-way valve.

7. The timing valve of claim 1 wherein,

said pilot valve element is controlled in dependence upon said fluid pressure and the movement of said rod.

a pilot valve including a valve element for controlling the fluid flow through said pilot valve, and

fluid actuating means including:

a cylinder, a piston slidably mounted in said cylinder and being detached from said timing spring, means for selectively applying fluid pressure to said piston to cause the piston to move in response thereto, and means for mechanically transferring the movement of said piston to said pilot valve element.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3996905 *Nov 25, 1974Dec 14, 1976Chrysler CorporationVacuum controls for internal combustion engines
US4354524 *Sep 15, 1980Oct 19, 1982Otis Engineering CorporationAutomatic reset pneumatic timer
US5030347 *Oct 30, 1989Jul 9, 1991Mordeki DroriMultiple filter elements with movable flushing assembly
Classifications
U.S. Classification251/54, 251/49, 137/624.14
International ClassificationF16K31/36, F16K31/365, F15B21/12, F15B21/00
Cooperative ClassificationF15B21/12, F16K31/365
European ClassificationF15B21/12, F16K31/365