US3343558A

US3343558A - Timing valves

Info

Publication number: US3343558A
Application number: US420271A
Authority: US
Inventors: Vita Raymond A De
Original assignee: United Shoe Machinery Corp
Current assignee: United Shoe Machinery Corp
Priority date: 1964-12-22
Filing date: 1964-12-22
Publication date: 1967-09-26
Anticipated expiration: 1984-09-26

Description

R. A. DE VITA TIMING' VALVES Sept. 26, 1967 Filed Dec. 22, 1964 I .CLLIC m vu m V0 nm W m w. m% fi w United States Patent 3,343,558 TIMING VALVES Raymond A. De Vita, Winchester, Mass., assignor to United Shoe Machinery Corporation, Flemington, N.J., a corporation of New Jersey Filed Dec. 22, 1964, Ser. No. 420,271 6 Claims. (Cl. 137-102) ABSTRACT OF THE DISCLOSURE A timing valve having a timing chamber of variable volume and a metering passage leading from the timing chamber to fluid pressure operated means for actuating the valve.

This invention relates to valves and has for its object the provision of a novel and improved timing valve which is of relatively simple and inexpensive construction but at the same time is effective and dependable in operation.

With the foregoing object in view, and in accordance with features of the invention, the herein illustrated valve, having a body portion provided with an inlet and an outlet passage and a valve for controlling the flow of fluid under pressure from the inlet passage to the outlet passage, together with fluid pressure operated means for moving the valve from a closed position to an open position in which the inlet passage is connected to the outlet passage, is provided with a timing chamber of variable volume which is in communication with the inlet passage through a passage in which there is interposed means for metering the flow of pressure fluid from the inlet passage to said chamber and with means for varying the volume of the timing chamber thereby to vary the time interval between the admission of fluid under pressure to the inlet passage and movement of the valve to open position. Preferably, and in accordance with another feature of the invention, the body portion of the valve is also provided with an exhaust passage and the valve is adapted in its closed position to prevent the flow of pressure fluid from the inlet passage to the outlet passage while connecting the outlet passage to the exhaust passage and in its open position to connect the inlet passage to the outlet passage and to shut off the outlet passage from the exhaust passage. More particularly, and in accordance with still another feature of the invention, the metering means comprises a plunger provided with a metering orifice of fixed diameter and which is loosely fitted within the passage leading from the inlet to the timing chamber and a valve seat is provided at the end of the last mentioned passage adjacent to the chamber against which the metering plunger is yieldingly held by a spring so that the metering plunger is adapted to restrict the flow of pressure fluid from the inlet passage to the timing chamber While permitting a relativelyfree flow of pressure fluid from the chamber to the inlet passage.

The above and other objects and features of the invention will appear in the following detailed description of the preferred embodiment illustrated in the accompanying drawings and will be pointed out in the appended claims.

In the drawings:

FIGS. 1 and 2 are views in section of a timing valve embodying the features of this invention, these figures showing the valve in difierent operating positions.

- The valve construction illustrated in the drawings comprises a body formed of four components, namely a lower cap member 10, an intermediate block 12, a cylindrical chamber forming element 14 and an upper cap member 16, these several components being held together in assembled relation, as shown, by means of four

studs

18, 18

"ice

(only two of which are visible) threaded into the lower cap member 10 and passing through the intermediate block 12, outside of the element 14 and through the block 16, and

clamp nuts

20, 20. Interposed between the lower cap member 10 and the intermediate block 12 is a gasket 21 while interposed between the intermediate block 12 and the chamber forming member 14 is a flexible and elastic diaphragm 22, the latter being held in place by a centering disc 24 and three clamp screws 26 (only one of which appears in the drawings).

The lower cap member 14 is provided with a central cylindrical recess 30 having an enlarged upper portion 32 and leading into this recess is an inlet passage 34, threaded at its outer end to receive a pipe or other conduit fitting. Formed in the intermediate block 12 is a central bore 40 in alignment with the recess 30 in the cap member 10 and having an enlarged upper portion 42. An outlet passage 44 intersects the bore 49, as shown, and this outlet passage has a threaded outer end similar to that of the inlet 34. Slidable within the bore 4%) is a main valve body portion 50 to the lower threaded end of which there is secured, by means of a nut 52, a valve disc 54 provided on its upper side with a valve facing 56 adapted to cooperate with a valve seat on the block 12 which is formed by a shallow circular recess 58, concentric with the bore 4i). At its upper end, the valve body portion 50 carries a piston 60 which is slidable within the enlarged upper portion 42 of the bore 40 and which is somewhat larger in diameter than the valve disc 54. A transverse 'bore 62 through the valve body portion 56 communicates at its opposite ends with axial grooves 64 (one of which is visible). A coil spring 66 constantly urges the main valve upwardly toward the position in which it is shown in FIG. 1.

Also extending through the intermediate block 12, and offset radially from the central bore 40, is a second and parallel bore 70 the lower end of which overlaps, slightly, the enlarged upper portion 32 of the recess 30. Loosely fitted within this bore, with an annular clearance space therearound, is a metering plunger 72 which is provided with an axially extending metering passage 74 of extremely small diameter (i.e., in the order of .004) and normally held yieldirrgly up against a sealing ring 76 by means of a coil spring 78. The centering plate 24 is provided with

apertures

80, 82 which are in alignment, respectively, with the

bores

40 and 70 and the diaphragm 22 is provided with an aperture 83 in line with the aperture 82. Slidable within the cylindrical chamber forming member 14 is a piston-like disc 84, upward movement of which is limited by means of an adjusting screw 86, threaded through the upper cap member 16 and provided with a knurled locknut 88.

A suitable ring-type sealing member is fitted within an angular groove in the periphery of the piston-like disc.

As suggested above, the herein illustrated valve is a socalled timing or timer valve and is adapted to connect the inlet passage 34 with the outlet passage 44 after a pre determined time interval has elapsed following the admission of fluid under pressure (e.g. compressed air) to the inlet passage. As shown in FIG. 1, prior to such admission of fluid under pressure to the inlet passage 34, the valve disc 54, with its facing 56 held against the valve seat provided by the recess 58, by means of the spring 66, cuts off communication between the inlet passage 34 and the outlet passage 44 while the latter is connected to exhaust through grooves 64, transverse bore 62, enlarged bore 42 and an exhaust passage 92 formed in the intermediate block 12. Because of friction between the inside of the member 14 and the sealing ring 90 the piston-like disc may remain in the position in which it is shown, or it may slowly descend under the action of gravity until it rests 3 on the centering disc 24. In either case, the operation of the valve is the same.

As fluid under pressure is admitted to the inlet passage 34, it also enters the bore 70 and adds to the force of the spring 78 in holding the metering plunger 72 firmly against the sealing ring 76. Fluid'under pressure also slowly bleeds through the small metering passage 74 and, passing through

apertures

82 and 83, enters the timing chamber formed by member 14 beneath the piston-like disc 84. If this disc had descended, as above suggested, it will now be elevated by the fluid under pressure to the position in which it is shown in FIGS. 1 and 2 and in any event the chamber beneath the piston-like disc will eventually be filled with the pressure fluid after a predetermined time interval has elapsed which interval will, of course, be a function of the rate of flow of the pressure fluid through the metering passage 74 and of the volume of the timing chamber. When this chamber has been filled the pressure of the fluid therein will build up and will act on the piston 60, through the aperture 80 and diaphragm 22, finally overcoming action of the spring 66 and fluid pressure acting on the valve disc 54 and the lower end of the main valve body portion 50 and moving the main valve downwardly from the position shown in FIG. 1. As the valve disc leaves its seat, the upward force acting on the main valve is greatly reduced so that it is shifted quickly down to the position in which it is shown in FIG. 2, thereby connecting the inlet passage 34 with the outlet passage 44 through the groove 64 and radial bore 62 in a minner which should be apparent. At the same time, communication between the outlet passage 44 and the exhaust passage 92 will be shut off by the piston 60.

As will be readily understood, the effective volume of the timing chamber beneath the piston-like disc 84 can be readily and quite accurately varied by means of the adjustable abutment screw 86 which is then held in adjusted position by the locknut 88. A sealing ring 94 beneath the piston 60 prevents leakage of the pressure fluid around the main valve body portion 50. When the device which is actuated by fluid under pressure supplied from the outlet passage 44, completes its stroke, pressure of the fluid will equalize on opposite ends of the metering plunger 72 which, however, will still be held in the position in which it is shown by the spring 78.

When the supply of fluid under pressure to the inlet.

passage 34 is discontinued, and this passage connected to exhaust, the pressure of the fluid in the timing chamber in the member 14 beneath the piston-like disc 84, will force the metering plunger 72 downwardly, thus connecting the timing chamber to exhaust through

apertures

82, 83, the clearance space around the plunger 72, bore 70, recess 30 and inlet passage 34. The coil spring 66 will then return the main valve to the position sohwn in FIG. 1 while the metering plunger will be returned to its normal poistion by the coil spring 78.

The novel valve construction which has been described in detail above is very effective and dependable in operation, especially becaues of the very accurate and uniform metering action of the fixed diameter orifice 74 in the plunger 72 which avoids difliculties frequently encountered when flow of pressure fluid into, or out of, a timing chamber is controlled by a so-called needle valve. Moreover, the regulation of the predetermined time interval of the novel valve by varying the volume of the timing chamber can be more readily and accuartely effected than is the case with a needle valve. In this connection, it will be understood that variation in the volume of the timing chamber, by means of the adjusting screw 86, provides a substantially proportional or linear control of the time interval, a result impossible to attain with a needle valve. Also, the novel timing valve arrangement lends itself particularly to the relatively simple and inexpensive construction herein illustrated, although it will be understood that other specific mechanical embodiments fall within the scope of the invention.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. A timing valve comprising a body portion provided with an inlet passage, an outlet passage and an exhaust passage, a valve for controlling the flow of fluid under pressure from said inlet passage to said outlet passage and from said outlet passage to said exhaust passage, means for yieldingly holding said valve in a closed position to prevent flow of pressure fluid from said inlet passage to said outlet passage while connecting said outlet passage to said exhaust passage, fluid pressure operated means for moving said valve to an open position in which said inlet passage and said outlet passage are in communication and said outlet passage is shut off from said exhaust passage, means providing a timing chamber in communication with said fluid pressure operated means, means providing a passage leading from said inlet passage to said chamber, and means in said last mentioned passage for metering the flow of fluid under pressure from said inlet passage to said chamber, said metering means comprising a plunger provided with a metering orifice and loosely fitted within the'passage between the inlet passage and said chamber, said plunger being adapted to serve as a valve for restricting the flow of pressure fluid from said inlet passage to said chamber through said metering orifice and to permit relatively free flow of fluid under pressure from said chamber to said inlet passage.

2. A timing valve comprising a body provided with an inlet passage an outlet passage and an exhaust passage, a valve for controlling the flow of fluid under pressure from said inlet passage to said outlet passage and from said outlet passage to said exhaust passage, means for yieldingly holding said valve in a closed position to prevent flow of pressure fluid from said inlet passage to said outlet passage while connecting said outlet passage to said exhaust passage, fluid pressure operated means for moving said valve to an open position in which said inlet passage and said outlet passage are in communication and said outlet passage is shut off from said exhaust passage, means providing a timing chamber of Variable volume in communication with said fluid pressure operated means, means providing a passage leading from said inlet passage to said chamber, means in said last mentioned passage for metering the flow of fluid under pressure from said inlet to said chamber, said metering means comprising a plunger provided with a metering orifice and loosely fitted within the passage between the inlet passage and said chamber, said plunger being adapted to serve as a valve for restricting flow of pressure fluid from said inlet passage to said chamber through said metering orifice while permitting relatively free flow of fluid under pressure from said chamber to said inlet passage, and means for varying the volume of said chamber thereby to vary the time interval between admission of fluid under pressure to the inlet passage and the movement of said valve to open position by the fluid pressure operated means.

3. A timing valve comprising a body provided with an inlet passage and an outlet passage, a valve for controlling the flow of fluid under pressure from said inlet passage to said outlet passage, means for yieldingly holding said valve in a closed position to prevent flow of pressure fluid from said inlet passage to said outlet passage, fluid pressure operated means for moving said valve to an open position in which said inlet passage and said outlet passage are in communication, means providing a timing chamber in communication with said fluid pressure operated means, means providing a passage leading from said inlet passage to said chamber, and means in said last mentioned passage for metering the flow of fluid under pressure from said inlet to said chamber, said metering means comprising a plunger provided with a metering orifice and loosely fitted within said last named passage, means for providing a valve seat at the end of said passage adjacent to said chamber, a spring yieldingly holding said plunger against said valve seat, whereby said plunger is adapted to restrict the flow of pressure fluid from said inlet passage into said chamber while permitting a relatively free flow of pressure fluid from said chamber to said inlet passage.

4. A timing valve comprising a body provided with an inlet passage and an outlet passage, a valve for controlling the flow of fluid under pressure from said inlet pas sage to said outlet passage, means for yieldingly holding said valve in a closed position to prevent flow of pressure fluid from said inlet passage to said outlet passage, fluid pressure operated means for moving said valve to an open position in which said inlet passage and said outlet passage are in communication, means providing a timing chamber of variable volume in communication with said fluid pressure operated means, means providing a passage leading from said inlet passage to said chamber, means in said last mentioned passage for metering the flow of fluid under pressure from said inlet passage to said chamber, said metering means comprising a plunger provided with a metering orifice and loosely fitted within said last named passage, means providing a valve seat at the end of said passage adjacent to said chamber, a spring yieldingly holding said plunger against said valve seat, whereby said plunger is adapted to restrict the flow of pressure fluid from said inlet passage into said chamber while permitting a relatively free flow of pressure fluid from said chamber to said inlet passage, and means for varying the volume of said chamber thereby to vary the time interval between admission of fluid under pressure to the inlet passage and the movement of said valve to open position by the fluid pressure operated means.

5. A timing valve comprising a body provided with an inlet passage, an outlet passage and an exhaust passage, a valve for controlling the flow of fluid under pressure from said inlet passage to said outlet passage and from said outlet passage to said exhaust passage, means for yieldingly holding said valve in closed position to prevent flow of pressure fluid from said inlet passage to said outlet passage while connecting said outlet passage to said exhaust passage, fluid pressure operated means for moving said valve to an open position in which said inlet passage and said outlet passage are in communication and said outlet passage is shut off from said inlet passage, means providing a timing chamber in communication with said fluid pressure operated means, means providing a passage leading from said inlet passage to said chamber, and means in said last named passage for metering the flow of fluid under pressure from said inlet to said chamber, said metering means comprising a plunger provided with a metering orifice and loosely fitted within said last named passage, means providing a valve seat at the end of said passage adjacent to said chamber, a spring yieldingly holding said plunger against said seat, whereby said plunger is adapted to restrict the flow of fluid from said inlet passage into said chamber while permitting a relatively free flow of pressure fluid from said chamber to said inlet passage.

6. A timing valve comprising a body provided with an inlet passage, an outlet passage and an exhaust passage, a valve for controlling the flow of fluid under pressure from said inlet passage to said outlet passage and from said outlet passage to said exhaust passage, means for yieldingly holding said valve in a closed position to prevent flow of pressure fluid from said inlet passage to said outlet passage while connecting said outlet passage to said exhaust passage, fluid pressure operated means for moving said valve to an open position in which said inlet passage and said outlet passage are in communication and said outlet passage is shut off from said exhaust passage, means providing a timing chamber of variable volume in communication with said fluid pressure operated means, means providing a passage leading from said inlet passage to said chamber, means in said passage for metering the flow of fluid under pressure from said inlet passage to said chamber, said metering means comprising a plunger provided with a metering orifice and loosely fitted within said last named passage, means providing a valve seat at the end of said passage adjacent to said chamber, a spring yieldingly holding said plunger against said seat, whereby said plunger is adapted to restrict the flow of pressure fluid from said inlet passage into said chamber while permitting a relatively free flow of pressure fluid from said chamber to said inlet passage, and means for varying the volume of said chamber thereby to vary the time interval between admission of fluid under pressure to the inlet passage and the movement of said valve to open position by the fluid pressure operated means.

References Cited UNITED STATES PATENTS 2,638,108 5/1953 Williams et a1. 137102 2,663,153 12/1953 Grant, Jr. 137110 2,716,997 9/1955 Crookston 137-102 2,819,865 1/1958 Olson 251-25 3,022,118 2/1962 Dobrikin 137102 X 3,269,157 8/1966 Ashley 137102 X M. CARY NELSON, Primary Examiner.

E. K. FEIN, R. I. MILLER, Assistant Examiners.

Claims

1. A TIMING VALVE COMPRISING A BODY PORTION PROVIDED WITH AN INLET PASSAGE, AN OUTLET PASSAGE AND AN EXHAUST PASSAGE, A VALVE FOR CONTROLLING THE FLOW OF FLUID UNDER PRESSURE FROM SAID INLET PASSAGE TO SAID OUTLET PASSAGE AND FROM SAID OUTLET PASSAGE TO SAID EXHAUST PASSAGE, MEANS FOR YIELDINGLY HOLDING SAID VALVE IN A CLOSED POSITION TO PREVENT FLOW OF PRESSURE FLUID FROM SAID INLET PASSAGE TO SAID OUTLET PASSAGE WHILE CONNECTING SAID OUTLET PASSAGE TO SAID EXHAUST PASSAGE, FLUID PRESSURE OPERATED MEANS FOR MOVING SAID VALVE TO AN OPEN POSITION IN WHICH SAID INLET PASSAGE AND SAID OUTLET PASSAGE ARE IN COMMUNICATION AND SAID OUTLET PASSAGE IS SHUT OFF FROM SAID EXHAUST PASSAGE, MEANS PROVIDING A TIMING CHAMBER IN COMMUNICATION WITH SAID FLUID PRESSURE OPERATED MEANS, MEANS PROVIDING A PASSAGE LEADING FROM SAID INLET PASSAGE TO SAID CHAMBER, AND MEANS IN SAID LAST MENTIONED PASSAGE FOR METERING THE FLOW OF FLUID UNDER PRESSURE FROM SAID INLET PASSAGE TO SAID CHAMBER, SAID METERING MEANS COMPRISING A PLUNGER PROVIDED WITH A METERING ORIFICE AND LOOSELY FITTED WITHIN THE PASSAGE BETWEEN THE INLET PASSAGE AND SAID CHAMBER, SAID PLUNGER BEING ADAPTED TO SERVE AS A VALVE FOR RESTRICTING THE FLOW OF PRESSURE FLUID FROM SAID INLET PASSAGE TO SAID CHAMBER THROUGH SAID METERING ORIFICE AND TO PERMIT RELATIVELY FREE FLOW OF FLUID UNDER PRESSURE FROM SAID CHAMBER TO SAID INLET PASSAGE.