GB2154707A

GB2154707A - Inlet poppet valve

Info

Publication number: GB2154707A
Application number: GB08502656A
Authority: GB
Inventors: Donald Jerome West
Original assignee: Ross Operating Valve Co
Current assignee: Ross Operating Valve Co
Priority date: 1984-02-22
Filing date: 1985-02-01
Publication date: 1985-09-11
Also published as: GB8502656D0; SE8500834D0; IT8519505A0; ES540574A0; FR2559870A1; GB2154707B; JPS60196471A; SE8500834L; ES8607504A1; DE8504318U1; KR850006597A; DE3505299A1; IT1183188B; DD232532A5; FR2559870B1; IN161083B; BR8500730A

Abstract

A two-position, four-way valve assembly incorporates poppet valve elements (72, 86, 88) mounted upon a single shaft (70) for simultaneous operation. Only one (72) of the valve elements is engageable selectively with a fixed valve seats (66, 68), the remaining valve elements (86, 88) being engageable with respective movable valve seats (42, 44) whereby dimensional variations due to manufacturing tolerances may be accommodated. Additionally, the valve elements and seats are sized relative to each other to create a net force due to the pressurized fluid acting thereon which force operates to maintain the valve elements in a stable condition in either of the two positions, to urge the respective movable valve seats into sealing engagement with the respective valve elements, and to return the movable valve seats to a predetermined position upon disengagement of the associated valve element. <IMAGE>

Description

SPECIFICATION Inline poppet valve Background and Summary of the Invention The present invention relates generally to valve assemblies and more particularly to multi-position, multi-way valve assemblies utilizing a plurality of poppet type valve members mounted on a single actuating shaft.

Heretofore it has been extremely difficult and costly to utilize poppet type valve members in multi-position, multi-way valve assemblies. One of the primary reasons for this difficulty resides in the fact that such valves typically provide a plurality of valve members or elements operated by a single actuating shaft. Because in poppet valves the valve member moves generally perpendicularly to the valve seat, it is necessary to position the respective valve seats within the valve assembly so as to assure a substantially simultaneous secure fluid-tight sealing engagement of all of the valve members therewith. This has required that exceedingly tight tolerances be adhered to which is not only very difficult in volume production but also is very costly.It is also very desirable with such multi-position, multi-way valves to design the valve so that it is stable or self-sustaining in the various positions thus eliminating the need to apply a continuous actuating force to maintain it in position.

The present invention overcomes these problems by providing a multi-position, multiway valve assembly such as for example a two position, four way valve assembly which avoids the need to adhere to such exceeding tight costly tolerances yet assures that the resulting valve assembly will provide a secure sealing relationship between each of the respective valve members and associated seats.

This is accomplished in the present invention by providing movable valve seats for all but one of the poppet valve members. The movable valve seats are designed so as to engage the valve member either simultaneously or slightly before the fixed seat is engaged by its valve member. When the movable yalve seats are engaged before the fixed seats they move along with the associated valve member until the fixed seat is engaged thereby providing for more normal tolerance variations between successive valve assemblies.

The present invention also provides a net pressure created force which is operable to maintain the valve assembly in either of its two positions. This is accomplished by selectively controlling the relative surface areas against which the pressurised fluid being controlled by the valve acts so as to thereby create a net pressure imbalance acting in a direction to hold the valve in the desired position. Thus in the present invention the only actuating force required is that necessary to shift the valve assembly from one position to the other and no external sustaining force is required to maintain it in that position.

Additional advantages and features of the present invention will become apparent from the subsequent description and the appended claims taken in conjunction with the accompanying drawings.

Brief Description of the Drawings Figure 1 is a section view of a two position, four way valve assembly in accordance with the present invention, the section being taken along a radial plane extending along the longitudinal axis thereof; and Figure 2 is a view similar to that of Fig. 1 showing an axial section of another embodiment of a two position, four way valve assembly, all in accordance with the present invention.

Description of the Preferred Embodiments Referring now to the drawings and in particular to Fig. 1, there is shown a valve assembly in accordance with the present invention indicated generally at 1 0.

Valve assembly 10 is a two position four way valve and includes a housing 1 2 having an opening 1 4 extending longitudinally therethrough. A plurality of radially extending spaced flanges 1 6, 18, 20, 22 divide the interior of housing 1 2 thereof into a plurality of adjacent chambers 24, 26, 28, 30, 32.

Each of the flanges 16, 18, 20, 22 has a bore 34, 36, 38, 40 respectively extending therethrough all of which are positioned coaxially with respect to each other. A fluid inlet opening 29 is provided in the sidewall of housing 1 2 and opens into inlet chamber 28 with a pair of longitudinally spaced adjacent outlet openings 27 and 31 opening into respective outlet chambers 26 and 30. Also a pair of exhaust passages 25 and 33 are provided in housing 1 2 which open into respective exhaust chambers 24 and 32.

A pair of movable valve seat members 42 and 44 are positioned within housing 1 2 being seated within bores 34 and 40 respectively. As shown, each movable valve seat member 42, 44 is generally cylindrical in shape and sized to be freely movably received within respective bores 34, 40. An annular groove 46, 48 is provided in each of the peripheries thereof which is adapted to receive a suitable sealing member 50 such as an 0ring for example which operates to create a sealing relationship with the sidewalls of each of bores 34 and 40.A generally radially extending annular flange portion 54, 56 is also provided around the outer periphery of each of the movable valve seat members 42, 44 and operates to abut surfaces 58 and 60 of flanges 1 6 and 22 respectively so as to provide a positive stop to limit axial inward movement of the respective valve seat mem bers 42, 44. The outer end surfaces 62, 64 of each of the movable valve seat members 42, 44 is suitably machined to provide a valve seating surface. As shown, valve seat members 42 and 44 project through respective bores 34 and 40 and extend slightly into respective chambers 26 and 30. Annular grooves 65, 67 are provided on the outer periphery of each of the valve seat members 42 and 44 adjacent the inner ends thereof into which are fitted retaining rings 69, 71 respectively.Retaining rins 69 and 71 operate to abut respective surfaces 73 and 75 of chambers 26 and 30 so as to limit axial outward movement of movable valve seat members 42 and 44. Preferably movable valve seat members will be moved into respective bores 34 and 40 from opposite axial ends of housing 1 2 via bores 94 and 94' respectively after which retaining rins 69 and 71 may be inserted through openings 27 and 31 and assembled thereto.

A pair of fixed valve seating surfaces 66 and 68 are also provided within housing 1 2 being positioned within inlet chamber 28 and in surrounding relationship to respective bores 36 and 38.

A shaft 70 is movably positioned within housing 1 2 and has an inlet poppet valve member 72 secured thereto approximately centered between opposite ends thereof by means of a pair of substantially identical oppositely extending elongated flanged spool members 74 and 76. Inlet poppet valve 72 comprises a generally washer shaped center core member 78 of suitable metal surrounded by a sheath 80 of a suitable rubber or polymeric composition. A pair of annular rib-like protrusions 82, 84 are integrally formed in the sheath 80 on opposite axial sides thereof adjacent the outer periphery. Ribs 82, 84 are designed to sealingly engage respective valve seating surfaces 66 and 68 surrounding bores 36 and 38.

A pair of substantially identical additional poppet valve members 86 and 88 are also secured to shaft 70 adjacent opposite axial ends thereof and in abutting relationship with the opposite respective ends of flanged spool members 74 and 76. In order to secure inlet poppet valve 72, flanged spool members 74, 76 and poppet valve members 86 and 88 in position on shaft 70, a suitable retaining ring 77 may be seated within a groove 79 provided adjacent one end of shaft 70. The other end of shaft 70 will preferably be threaded to receive a lock nut 81 which may be suitably tightened against poppet valve member to thereby securely retain the components in position on shaft 70. As poppet valves 86 and 88 are substantially identical, only one will be described in detail with corresponding portions of the other being indicated by like numbers primed.

As shown, poppet valve 86 comprises a generally cylindrically shaped member 90 having a recess 92 provided on the axially outwardly facing surface thereof which is designed to receive retaining ring 77 (corresponding recess 92' in poppet valve 88 receives lock nut 81) and a diameter such as to enable it to be freely movably received within an end bore 94 in housing 12. An annular groove 96 is provided in the periphery thereof adjacent the outer end thereof which is designed to receive a suitable seal 98 which engages the sidewalls of bore 94. An annular axially inwardly opening irregularly shaped cavity 100 is formed in valve member 86 within which is positioned a comparably shaped sealing member 102 which may be fabricated from any suitable rubber or polymeric composition.The leading edges of sealing member 102 define a generally annular axially projecting rib 104 which is designed to sealingly engage valve seat surface 62 of movable valve seat member 42. Preferably, in order to prevent excessive axial compression of sealing member 102 and possible distortion of axially projecting rib 104, spool members 74 and 76 are each provided with annular axially extending flange portions 83, 85 surrounding shaft 70 which project through sealing members 102, 102' and engage the bottom of cavities 100, 100'.

It should be noted that the diameter A of the sealing ribs 82, 84 of inlet poppet valve 72 is substantially greater than the diameter B of substantially identical movable valve seat members 42, 44 which in turn is greater than the diameter C of sealing rib 104 on poppet valves 86 and 88 and it is these differences in relative diameters which enable the valve assembly of the present invention to be stable and self-sustaining in either of its two positions as well as operates to effect return movement of the respective movable valve seat members 86, 88 during switching thereof as explained in further detail below.

More specifically, with the valve assembly in the position shown in Fig. 1, it is noted that the inlet fluid pressure within inlet chamber 28 will exert a net force directed to the left as shown on inlet poppet valve 72 proportional to the diameter A of sealing rib 82, it being understood that outlet chamber 26 is in open communication with exhaust chamber 24 when valve assembly 10 is in the position shown and hence at a low or atmospheric pressure. Opposing the force exerted on inlet poppet valve 72, however, will be an oppositely directed force resulting from the fluid pressure acting on the inner surfaces of the movable valve seat 44 and poppet valve 88.

This opposing force will be proportional to the diameter B of movable valve seat member 44 which, as noted above, is less than the diameter A of sealing rib 82. Hence, because the inlet chamber 28 and outlet chamber 30 will be at substantially equal pressure and the net surface area of the inlet poppet valve 72 against which this pressure acts is greater than the net surface area against which this pressure acts presented by the movable valve seat 44 and poppet valve 88 together, there will be a net force acting in the direction to maintain inlet poppet valve 72 in the position shown. Similarly, when shaft 70 is shifted to the right as shown, a substantially identical relationship between inlet poppet valve 72, movable valve seat 42 and poppet valve 86 will be established.Thus, the resulting pressure imbalance will maintain the valve assembly stable in either of the two positions without the need for application of an ongoing external force.

A similar pressure imbalance is also employed in order to reposition the movable valve seat members 42 and 44 as the valve assembly 10 is actuated. In this application there will be a net force acting on the engaged movable valve seat 42 or 44 which is proportional to the difference between diameter B thereof and diameter C of the engaging sealing rib 104 or 104' of poppet valve 86 or 88. Thus, for example, as the shaft 70 is actuated to the right as viewed in Fig. 1, this net force will cause the movable valve seat 44 and associated poppet valve 88 to move synchronously until such time as retaining ring 71 abuts surface 75 of flange 22.

Thereafter continued actuating movement will then unseat poppet valve 88 thereby placing outlet chamber 30 in communication with exhaust chamber 32 and associated passage 33. It should be noted that this net unbalanced force acting on the movable valve seats 42, 44 also operates to continuously urge the seating surfaces 62, 64 into sealing engagement with the respective sealing rib 104, 104' when in an engaged position thus aiding in assuring a fluid tight-seal therebetween.

It should also be noted that while preferably the maximum distance D between sealing ribs 104, 104' and associated sealing surface 62, 64 of movable valve seats 42, 44 will be identical to the distance E between sealing ribs 82, 84 of inlet poppet valve 72 and its associated seating surfaces 66, 68. However, in actual practice, it is exceedingly difficult to achieve the necessary extremely tight tolerances required without excessively high costs.

In the present invention it is merely necessary to assure that dimension D is no greater than dimension E as any additional movement required to seat sealing ribs 82 or 84 against their respective sealing surfaces 66, 68 will be accommodated by axial movement of one or the other of movable valve seats 42, 44.

Thus, as may now be appreciated, the present invention provides a relatively simple construction for utilizing poppet type valves in a multi-position, multi-way valve without the extremely high costs necessary to achieve very tight tolerances.

Referring now to Fig. 2, another embodiment of valve assembly in accordance with the present invention is shown being generally indicated at 106. Valve assembly 106 employs the same pressure differential concepts described above, however, in addition thereto provides auxiliary biasing means for the mov able valve seat members as more fully described below.

Valve assembly 106 includes an elongated housing 108 having a plurality of generally laterally inwardly opening passages 11 0, 112, 114, 116, 118 provided therein including a single inlet passage 114, a pair of outlet passages 112, 11 6 on opposite sides thereof and a pair of exhaust passages 110, 11 8 adjacent opposite ends of housing 108. In this embodiment, housing 108 has an elongated bore 1 20 extending therethrough which is of substantially constant diameter and which is designed to receive multi-part sleeve assembly 122.

Sleeve assembly 1 22 comprises a pair of substantially identical outer end sleeves 124, 1 26 extending inwaerdly from opposite ends of housing 108 and a pair of substantially identical inner sleeve members 128, 1 30 positioned centrally within bore 1 20 in abutting relationship and between the inner ends of outer sleeve members 124, 126. A plurality of axially spaced grooves 1 32 are provided in the outer surface of each of the outer and inner sleeves 124, 126, 128, 1 30 to accommodate seals 1 34 for creating a sealing relationship with the sidewalls of bore 1 20.

Outer sleeve 1 24 has a generally radially inwardly extending relatively wide flange portion 1 36 provided therein within which is positioned a generally cylindrically shaped movable valve seat member 1 38. An annular groove 1 40 is provided in the radially inner surface of flange 1 36 to accommodate suitable sealing means 142 for sealing engagement with movable valve seat member 1 38.

Seat member 1 38 is similar to seat members 42, 44 described above and includes a valve seating surface 1 44 on one end thereof and an annular radially outwardly extending flange portion 1 46 adjacent but spaced slightly inwardly from the opposite end thereof.

A movable exhaust poppet valve assembly 148 is also movably positioned within outer sleeve 1 22 being secured to a suitable actuating shaft 1 50 such as by threaded nut 1 52.

Poppet valve assembly 1 48 comprises a generally irregularly, somewhat cup-shaped valve member 1 54 having an annular groove 1 56 in the periphery thereof within which a suitable seal 1 58 is positioned. A generally dovetail-shaped annular groove 1 60 is provided in an axially inwardy facing surface of valve member 1 54 and has a suitable rubber or polymeric composition sealing ring 1 62 interlocked therein.As shown, the inner end (with respect to housing 108) of sealing ring 1 62 projects slightly beyond the inner surface of valve member 1 54 and is designed to sealingly engage the facing valve seat surface 144 provided on movable valve member 1 38 so as to thereby close off communication between outlet passage 11 2 and exhaust pas sage 110.

Center sleeve 1 28 is also generally cylindri cal in shape and relatively short in the axial direction. A generally radially inwardly extend ing flange 1 64 is provided at the axially outer end thereof, one side of which has provided thereon a suitable resilient sealing member 166.The opposite axial surface has a relatively small annular notch 1 68 provided at the inner edge which provides a seat for one end of a helical coil compression spring 1 70. The other end of spring 1 70 is seated against the axially inwardly facing surface of flange 146 of movable valve seat member 1 38. Spring 1 70 operates to provide additional biasing means to urge movable valve seat 1 38 into the position shown as well as to provide additional insurance of secure seating engage ment of seat surface 144 with sealing ring 162.

As thus far described each of the elements referred to above are substantially identical to corresponding elements provided in the right half (as viewed in Fig. 2) of valve assembly 106. Accordingly, the same reference numbers primed have been applied to these corresponding elements.

An inlet poppet valve 1 72 is also provided on shaft 1 50 being secured between a pair of oppositely extending flanged members 174, 1 76 the opposite ends of which maintain poppet valve assemblies 148, 148' in proper axial spaced relationship. As shown, inlet poppet valve 1 72 is generally cylindrical in shape and has a pair of axially projecting annular rib members 178, 1 80 provided on axially opposite sides thereof which are designed to sealingly engage respective sealing rings 1 66 and 166' secured to inner sleeves 1 28 and 1 30 respectively.

Similarly to that described above, valve assembly 106 is also designed to employ the various pressure differentials to enable the valve assembly to be stable in either of the two positions as well as to assist in both urging movable valve seats 138, 138' into sealing engagement with sealing rings 1 62, 1 62' as well as returning them to an extended position such as movable valve seat 1 38 is shown in Fig. 2. Accordingly, the diameter F of the annular ribs 1 178, 1 80 of inlet poppet valve 1 72 is greater than the diameter G of movable valve seats 1 38, 138'.

Also diameter G is greater than the diameter H of sealing rings 1 62, 162'. Also, as mentioned above movable valve seats 138, 138' projects through flanges 1 36, 136' a sufficient distance so as to assure the distance I between sealing rings 162, 162' and valve seat surfaces 144, 144' is less than the distance J between annular ribs 1 78, 1 80 and valve seat surfaces 166, 1 66' whereby sealing rings 162, 162' will engage surfaces 1 44 and 144' of movable valve seats 138, 138' and effect axial movement thereof until inlet poppet valve 1 72 is fully seated thereby assuring any dimensional variations due to manufacturing tolerance will be easily accommodated.

Thus, there is provided by the present invention a unique valve assembly which employs a plurality of poppet valves mounted on a single actuating shaft and designed to seat on a combination of fixed and movable valve seats whereby manufacturing tolerances may be easily accommodated.

While it will be apparent that the preferred embodiments of the invention disclosed are well calculated to provide the advantages and features above stated, it will be appreciated that the invention is susceptible to modification, variation and change without departing from the proper scope or fair meaning of the subjoined claims.

Claims

1. An improved inline poppet valve assembly comprising a housing element supporting a first valve seating surface and a second valve seating surface, a pair of poppet valves having respective first and second sealing surfaces movably supported within said housing, said first poppet valve seating surface being movable into and out of sealing engagement with said first valve seating surface and said second poppet valve seating surface being movable into and out of sealing engagement with said second seating surface, and an actuating element for simultaneously moving said poppet valves between a first position in which said first seating surface is engaged by said first sealing surface and said second sealing surface is spaced from said second seating surface and a second position wherein said first sealing surface is spaced from said first sealing seating surface and said second sealing surface is engaged with said second seating surface, one of said second valve surfaces being movable relative to its respective supporting element in order to insure sealing engagement between said valves and said valve seating surfaces whereby manufacturing tolerances with respect to the positioning of said valve surfaces may be accommodated, and means for applying a fluid pressure differential to said relatively movable surface when said poppet valves are in a position that said surface is not engaged with its cooperating valve surface for urging said relatively movable surface toward its cooperating valve surface.

2. A poppet valve assembly as set forth in claim 1 wherein said actuating element comprises a shaft, said pair of poppet valves being fixed to said shaft in axial spaced relationship, the relatively movable valve surface comprising one of said valve seating surfaces.

3. A poppet valve assembly as set forth in claim 1 wherein said movable valve seating surface is provided on one end of a cylindrical member, said cylindrical member being sealingly movable supported within a bore provided in said housing element.

4. A poppet valve assembly as set forth in claim 3 wherein the fluid pressure differential on said cylindrical member effects a net axially directed force acting theron in a direction to urge said cylindrical member away from the other valve seating surface.

5. A poppet valve assembly as set forth in claim 4 wherein said force is supplemented by biasing means within said housing.

6. A poppet valve assembly as set forth in claim 5 wherein said biasing means comprise a helical coil spring.

7. A poppet valve assembly as set forth in claim 4 wherein said force is exerted thereon by fluid pressure.

8. A poppet valve assembly as set forth in claim 7 wherein said force is generated by different effective areas on opposite sides of said cylindrical member.

9. A poppet valve assembly as set forth in claim 1 wherein the remaining valve surfaces are fixed relative to their supporting elements and said first poppet valve has a net axially directed force acting thereon when said first poppet valve is in sealing engagement with said first valve seating surface, said net axial force being in a direction to urge said first poppet valve against said valve seat surface.

10. A poppet valve assembly as set forth in claim 9 wherein said net axial direct force is created by pressurized fluid flowing through said valve assembly.

11. An inline poppet valve assembly comprising an elongated housing element having a bore extending longitudinally therethrough and means dividing said bore into a plurality of chambers, each of said chambers communicating with an outwardly opening passage in said housing, an elongated actuating shaft element movably positioned within said bore, a plurality of poppet valve members supported by said shaft element, first and second of said poppet valve members being positioned adjacent opposite ends of said shaft and said first and second poppet valve members each being movable between open and closed positions to selectively place adjacent first and second pairs of said plurality of chambers in fluid communication, a third poppet valve member supported by said shaft element between said first and second poppet valve members, said third poppet valve member being movable between a first position wherein it operates to place another of said chambers in fluid communication with an adjacent one of said first pair of chambers and a second position wherein it operates to place said another of said chambers in fluid communication with an adjacent one of said second pair of chambers, means defining first and second axially spaced valve seat members supported by said housing element and engageable by said third poppet valve member when in a respective one of said first and second positions, a third valve seat member supported by said housing element and disposed between said first pair of chambers and selectively engageable by said first poppet valve member when in a closed position, a fourth valve seat member supported by said housing element and disposed between said second pair of chambers and selectively engageable by and movable by said second poppet valve member when in a closed position, at least one of said members being movable relative to its supporting element for accommodating for variation in axial positioning of the members, and means for creating a fluid force on said movable member for urging it relative to its supporting element in a direction toward its engaging member.

1 2. A poppet valve assembly as set forth in claim 11 wherein the movable member comprises one of the valve seat members.

1 3. A poppet valve assembly as set forth in claim 1 2 wherein the third and fourth valve seat members are movable relative to the supporting housing element and are biased by fluid pressure toward the first and second poppet valve members.

1 4. A poppet valve assembly as set forth in claim 11 wherein said poppet valve assembly is operative to selectively control the flow of a pressurized fluid therethrough and said third poppet valve member has an axially facing surface area against which said pressurized fluid acts to provide an axial force thereon acting in first direction which is greater than an oppositely directed axially force acting on said first and second poppet valve members and their associated valve seat members when in engaging relationship whereby said first and second poppet valve members and said third poppet valve member will be held in a set position by said pressurized fluid.

1 5. A poppet valve assembly as set forth in claim 1 3 wherein said means dividing said bore into a plurality of chambers comprise sleeve means fitted within said bore, said sleeve means including first and second flange means for supporting said third and fourth valve seat members respectively and other flange means defining said first and second valve seat members.

1 6. A poppet valve assembly as set forth in claim 1 5 wherein said sleeve means comprise a plurality of sleeve segments positioned in end to end abutting relationship.

1 7. A poppet valve assembly as set forth in claim 11 wherein said means dividing said bore into a plurality of chambers comprise integrally formed axially spaced flange means provided in said housing, said first and second fixed valve seat being formed on respective adjacent ones of said flange means.

18. A poppet valve assembly substantially as described herein with reference to and as illustrated in Fig. 1 of the accompanying drawings.

1 9. A poppet valve assembly substantially as described herein with reference to and as illustrated in Fig. 2 of the accompanying drawings.