WO2019160605A1

WO2019160605A1 - Valve stem and disc carrier assembly

Info

Publication number: WO2019160605A1
Application number: PCT/US2018/066794
Authority: WO
Inventors: Steven M. MESNER; Greg A. EDGAR
Original assignee: Parker-Hannifin Corporation
Priority date: 2018-02-19
Filing date: 2018-12-20
Publication date: 2019-08-22

Abstract

A refrigeration valve (100) including a valve body (300) having a valve seat (1) and a stem/carrier assembly (200) moveable between an open position and a closed position within the refrigeration valve (100) is provided. The stem/carrier assembly (200) includes a valve stem (2) having an actuator end (11) and a socket end (10, 13). A face of the socket end (10, 13) has a curvilinear surface (10A, 10). The stem/carrier assembly (200) also includes a disc carrier (3) having a stem-receiving end and a valve seat end (3B). The stem-receiving end defines a stem socket (13) for receiving the socket end (10, 13) of the valve stem (2). A terminal face (12) of the stem socket (13) has a conical surface (12A) for cooperative engagement with the curvilinear surface (10A, 10) of the socket end (10, 13) of the valve stem (2) to allow relative movement of the valve stem (2) relative to the disc carrier (3) when the stem/carrier assembly (200) is in the closed position.

Description

TITLE: VALVE STEM AND DISC CARRIER ASSEMBLY

Related Applications

This application claims priority to U.S. Provisional Patent Application No. 62/631 ,973 filed on February 19, 2018, the entire disclosure of which is hereby incorporated by reference.

Field of Invention

The present invention relates generally to valves, and more particularly to a valve stem and disc carrier assembly for a refrigeration valve.

Background of the Invention

Conventional refrigeration valves are opened and closed by moving a valve stem that is coupled to a disc carrier. Typical valves utilize a manually operated valve stem with a disc carrier that can be tightened against a valve seat to close the valve. It is generally desirable to have a robust joint between the valve stem and disc carrier to improve functionality of the valve, including as pertaining to the valve stem and disc carrier assembly. For example, it is desirable to provide a joint between the valve stem and disc carrier that is strong enough to withstand pressures when flow in the valve is reversed. This may occur, for example, when a valve is mistakenly installed in a reverse flow position. Additionally, because forces increase exponentially with the area of the disc carrier as the size of the valve increases, it is also desirable to provide a joint that is strong enough to pull the disc carrier off of the valve seat with the valve stem when the valve is under its maximum allowable working pressure.

Furthermore, according to valve standards used in the refrigeration industry, the disc carrier cannot turn with the valve stem on the valve seat after coming into contact with the valve seat. Therefore, it is desirable to have some form of relative movement between the valve stem and disc carrier after the disc carrier comes into contact with the valve seat in the valve body such that as the valve stem is turned, the disc carrier does not turn with the valve stem against the valve seat. Flowever, in typical configurations in which the valve stem and disc carrier are not permanently coupled to one another, media flowing through the valve in the open position (i.e. , when the disc carrier is not in contact with the valve seat) may cause the disc carrier to spin freely on the valve stem. This may cause premature failure of the joint between the valve stem and the disc carrier.

Additionally, it is desirable to allow for some axial alignment of the valve stem and disc carrier with the valve seat such that the closing of the valve may be accomplished with minimal force.

Summary of the Invention

Aspects of the present disclosure relate to an easily assembled, permanent joint between the valve stem and disc carrier to form a valve stem and disc carrier assembly (hereinafter referred to as a“stem/carrier assembly”) of a refrigeration valve. The stem/carrier assembly may be assembled without special tooling or fixtures and allows for pivotal and rotational movement between the valve stem and disc carrier for accurate axial alignment with the valve seat so that the valve stem and disc carrier assembly form a robust seal against the valve seat. The resulting strength, axial movement, rotational, and anti-rotational features of the stem/carrier assembly provide a desirable refrigeration valve.

The stem/carrier assembly may be tension loaded to prevent the free rotation of the disc carrier on the valve stem with passing media flow when the valve is in the open position and the disc carrier is not in contact with the valve seat. This may be accomplished by a retaining ring fitted into grooves on the valve stem and the disc carrier, and a resilient member fitted between the valve stem and the disc carrier to provide tension on the retaining ring against the grooves. In the open position of the valve, the resilient member provides sufficient force on the retaining ring against the groove on the disc carrier to prevent the disc carrier from spinning on the valve stem when disc carrier is exposed to passing media flow. In the closed position, however, when the closing forces from the valve stem are transmitted to the disc carrier and the disc carrier makes contact with the valve seat of the refrigeration valve, the resilient member is compressed and the force on the retaining ring against the groove is relaxed, thereby allowing for relative movement between the valve stem and the disc carrier. This relative movement is sufficient to prevent rotation of the disc carrier against the valve seat as the valve stem rotates.

An aspect of the invention, therefore, is a refrigeration valve including a valve body having a valve seat and a stem/carrier assembly moveable between an open position and a closed position within the refrigeration valve. The stem/carrier assembly includes a valve stem having an actuator end and a socket end. A face of the socket end includes a curvilinear surface. The stem/carrier assembly also includes a disc carrier having a stem -receiving end and a valve seat end. The stem- receiving end defines a stem socket for receiving the socket end of the valve stem.

A terminal face of the stem socket includes a conical surface for cooperative engagement with the curvilinear surface of the socket end of the valve stem to allow relative movement of the valve stem relative to the disc carrier when the stem/carrier assembly is in the closed position.

Another aspect of the invention is a stem/carrier assembly moveable between an open position and a closed position within a refrigeration valve. The stem/carrier assembly includes a valve stem having an actuator end and a socket end. A face of the socket end includes a curvilinear surface. The stem/carrier assembly also includes a disc carrier having a stem -receiving end and a valve seat end. The stem- receiving end defines a socket for receiving the socket end of the valve stem. A terminal face of the stem socket includes a conical surface for cooperative

engagement with the curvilinear surface of the socket end of the valve stem to allow relative movement of the valve stem relative to the disc carrier when the stem/carrier assembly is in the closed position.

Another aspect of the invention is a method of operating a stem/carrier assembly for a refrigeration valve. The method includes providing a valve stem having an actuator end, a socket end, and a stem groove circumscribing an outer periphery of the socket end, and providing a disc carrier having a valve seat end, a stem-receiving end defining a stem socket, and a carrier groove circumscribing an inner periphery of the stem socket. The method also includes disposing a resilient member within the stem socket of the disc carrier and positioning a retaining ring on the valve stem in a starting position circumscribing the socket end of the valve stem. The method then includes inserting the socket end of the valve stem into the stem socket of the disc carrier such that the retaining ring is pushed into the stem groove, and further inserting the socket end of the valve stem into the stem socket of the disc carrier such that the stem groove aligns with the carrier groove and the retaining ring moves to a secured position. When in the secured position, the retaining ring is disposed in the stem groove and the carrier groove. The stem/carrier assembly is moveable between an open position and a closed position to regulate fluid flow within the refrigeration valve.

These and further features of the present invention will be apparent with reference to the following description and attached drawings. In the description and drawings, particular embodiments of the invention have been disclosed in detail as being indicative of some of the ways in which the principles of the invention may be employed, but it is understood that the invention is not limited correspondingly in scope. Rather, the invention includes all changes, modifications and equivalents coming within the spirit and terms of the claims appended hereto. Features that are described and/or illustrated with respect to one embodiment may be used in the same way or in a similar way in one or more other embodiments and/or in

combination with or instead of the features of the other embodiments.

Brief Description of the Drawings

Figure 1 is a side view of an embodiment of a refrigeration valve.

Figure 2 is a cross-sectional view of the refrigeration valve of Figure 1 taken in the direction of longitudinal axis A.

Figure 3 is an enlarged cross-sectional view of an exemplary stem/carrier assembly of the refrigeration valve of Figures 1 -2.

Figure 4 is a flowchart of a method of operating the stem/carrier assembly of Figure 3.

Detailed Description

Embodiments of the present invention will now be described with reference to the drawings, wherein like reference numerals are used to refer to like elements throughout. It will be understood that the figures are not necessarily to scale.

Figures 1 -2 show an exemplary refrigeration valve 100. The refrigeration valve 100 includes a valve body 300 and a valve stem and disc carrier assembly 200 (hereinafter referred to as the“valve stem/carrier assembly” 200). The valve body 300 includes a valve seat 1. The valve seat 1 may be annular; however the valve seat 1 may alternatively be of any suitable shape. The valve stem/carrier assembly 200 is moveable along a longitudinal axis A relative to the valve seat 1 , between an open and closed position within the valve 100. When the valve stem/carrier assembly 200 is in the open position, the valve stem/carrier assembly 200 is spaced apart from the valve seat 1 such that a fluid media flow may pass through the valve 100. When the stem/carrier assembly 200 is in the closed position, the valve stem/carrier assembly 200 is sealed against the valve seat 1 to obstruct fluid media flow through the valve 100. The valve 100 may also include a bonnet 30 disposed on the valve body 300 that circumscribes an actuator end 11 of the valve stem 2 and packing nut 32 disposed between the bonnet 30 and the actuator end 11 of the valve stem 2 (see Figure 3, as described in more detail below). The valve 100 may also include a gasket 34 disposed between the bonnet 30 and the valve body 300 for sealing the bonnet 30 against the valve body 300. The bonnet 30 is coupled to the valve body 300 with screws 38.

Figure 3 depicts an exemplary valve stem/carrier assembly 200 of the valve 100 in isolation. The valve stem/carrier assembly 200 includes a valve stem 2 and disc carrier 3. The valve stem 2 has an actuator end 11 and a socket end 10. An end face of the socket end 10 includes a first surface and a second surface circumscribing the first surface. In an embodiment, for example, the end face of the socket end 10 may include a first, curvilinear surface 10a and a second, flat surface 10b circumscribing the curvilinear surface 10a. The flat surface 10b may be, for example, annular. The curvilinear surface 10a may be, for example, a hemispherical surface or a segment of a sphere or ellipsoid, and in an embodiment, the curvilinear surface 10a may be convex.

The disc carrier 3 has a stem-receiving end 3a and a valve seat end 3b. The stem-receiving end 3a defines a stem socket 13 for receiving the socket end 10 of the valve stem 2 during assembly of the stem/carrier assembly 200, as will be described in more detail below. The stem-receiving end 3a of the disc carrier 3 may include a lead chamfer 20 to facilitate insertion of the socket end 10 of the valve stem 2 into the disc carrier 3 during assembly. The stem socket 13 is a generally cylindrical bore in the disc carrier 3 that terminates at a terminal face 12. Terminal face 12 of the stem socket 13 may include a first surface and a second surface circumscribing the first surface. In an embodiment, the terminal face 12 of the stem socket 13 includes a first, conical surface 12a and a second, flat surface 12b that circumscribes the conical surface 12a and is perpendicular to a longitudinal axis A of the stem/carrier assembly 200. The conical surface 12a is configured to

cooperatively engage with the curvilinear surface 10a of the socket end 10 of the valve stem 2 when the stem/carrier assembly 200 is assembled and the stem/carrier assembly 200 is in the closed position. In an embodiment, therefore, the conical surface 12a may be concave when the curvilinear surface 10a of the socket end 10 of the valve stem 2 is convex. When the stem/carrier assembly 200 is in the closed position, the interface between the conical surface 12a and the curvilinear surface 10a of the valve stem 2 may allow for relative movement (rotational and pivotal) between the disc carrier 3 and valve stem 2. Such movement may allow the disc carrier 3 and valve stem 2 to accommodate any axial misalignment with the valve seat 1 , thereby facilitating a robust seal with the valve seat 1 even when the stem/carrier assembly 200 is not precisely axially aligned with the valve seat 1 in the closed position.

The flat surface 10b of the valve stem 2 and the flat surface 12b of the stem socket 13 of the disc carrier 3 provide surfaces for receiving a resilient member 6, such as a wave spring. The resilient member 6, therefore, may be disposed between the flat surface 10b of the socket end 10 of the valve stem 2 and the flat surface 12b of the terminal face 12 of the stem socket 13. The stem/carrier assembly 200 may also include a sealing disc 7 disposed on the valve seat end 3b of disc carrier 3 for sealing against the valve seat 1 of the valve body 300 of the refrigeration valve 100 when the stem/carrier assembly 200 is in the closed position. The stem/carrier assembly 200 may also include, therefore, a sealing disc retainer 8, for retaining the sealing disc 7 on the valve seat end 3b of the disc carrier 3. The sealing disc retainer 8 may include a sealing disc retaining ring 8a and a washer 8b. When the valve seat 1 is annular in shape, for example, the sealing disc 7, sealing disc retainer 8, and sealing disc retaining ring 8a may be annular as well.

The valve stem 2 includes a stem groove 4 circumscribing an outer periphery of the socket end 10 of the valve stem 10 for housing a retaining ring 5. The stem groove 4 may include a tapered surface 24 on a side of the stem groove 4 nearest the end face of the socket end 10 of the valve stem 2. The disc carrier 3 includes a carrier groove 22 circumscribing an inner periphery of the stem socket 13. When the stem/carrier assembly 200 is assembled, the stem groove 4 and the carrier groove 22 house the retaining ring 5 for an enhanced permanent joint between the valve stem 2 and the disc carrier 3.

Accordingly, with reference to Figure 4, a method of operating the stem/carrier assembly 200 is depicted. In step 300, the method includes providing the valve stem 2 having an actuator end 11 , a socket end 13, and a stem groove 4 circumscribing an outer periphery of the socket end 13 of the valve stem 2. Additionally, in step 302, the method includes providing the disc carrier 3 having a valve seat end 3b, a stem-receiving end 3a defining a stem socket 13, and a carrier groove 22

circumscribing an inner periphery of the stem socket 13.

To assemble the stem/carrier assembly 200, the method includes, at step 304, disposing the resilient member 6 within the cylindrical bore of the stem socket 13 of the disc carrier 3. In an embodiment, the resilient member 6 is disposed against the flat surface 12b of the terminal face 12. The method also includes, at step 306, sliding the retaining ring 5 over the socket end 10 of the valve stem 2 and positioning the retaining ring 5 on the valve stem 2 in a starting position

circumscribing the socket end 10 of the valve stem 2. A small portion of grease may be disposed on the curvilinear surface 10a of the valve stem 2, and on the lead chamfer 20 of the stem-receiving end 3a of the disc carrier 3 to facilitate insertion of the valve stem 2 into the stem socket 13 of the disc carrier 3.

The stem 2 and disc carrier 3 are then pressed together using a small press and a minimal amount of force so that the socket end 10 of the valve stem 2 enters the stem socket 13 of the disc carrier 3. The method therefore includes, at step 308, inserting the socket end 10 of the valve stem 2 into the stem socket 13 of the disc carrier 3 such that the lead chamfer 20 pushes the retaining ring 5 into the stem groove 4. The lead chamfer 20 on the disc carrier 3 also compresses the retaining ring 5 further into the groove 4 of the valve stem 2 as the socket end 10 of the valve stem 2 enters the stem socket 13, allowing the valve stem 2 to further enter and fit within the smaller diameter of the stem socket 13. In an alternative embodiment, the method may include positioning the retaining ring 5 directly in the stem groove 4. In an embodiment, the socket end 10 of the valve stem 2 may be inserted into the stem socket 13 of the disc carrier 3 such that the flat surface 10b of the end face of the socket end 10 of the valve stem 2 contacts the resilient member 6 in the stem socket 13, and the curvilinear surface 10a of the socket end 10 of the valve stem 2 bottoms against the conical surface 12a of the stem socket 13.

The method then includes, at step 310, further inserting the socket end 10 of the valve stem 2 into the stem socket 13 of the disc carrier 3 such that the stem groove 4 aligns with the carrier groove 22, and the retaining ring 5 moves to a secured position disposed in the stem groove 4 and the carrier groove 22. When the stem groove 4 and the carrier groove 22 of the stem socket 13 align, the inward compression on the retaining ring 5 created by the lead chamfer 20 will release and the retaining ring 5 will expand outward into the carrier groove 22 to create a permanent joint which can only come apart through destructive means. As the diameter of the carrier groove 22 is smaller than a natural state of the retaining ring 5, however, the retaining ring 5 is still in a compressed state when it snaps out into the carrier groove 22, and the internal diameter of the retaining ring 5 is still smaller than the outer diameter of the valve stem 2 that it was initially slid over. The retaining ring 5 may create an audible noise and/or tactile feedback when the retaining ring 5 snaps into the carrier groove 22, thereby providing feedback to indicate that the assembly process is complete. In one embodiment, the stem groove 4 and the carrier groove 22 may align and the retaining ring 5 may expand into the carrier groove 22 before the curvilinear surface 10a contacts or engages the conical surface 12a.

Once the stem/carrier assembly 200 is assembled, the method may include, at step 312, moving the stem/carrier assembly 200 to the open position. When the stem/carrier assembly 200 is in the open position, the resilient member 6 is expanded and creates a force on the stem groove 4 and the retaining ring 5 against the carrier groove 22 such that the disc carrier 3 does not rotate relative to the valve stem 2. Furthermore, as the resilient member 6 provides a force on the valve stem 2 in a direction away from the stem socket, an outward bias is created on the retaining ring 5 by the tapered surface 24. Accordingly, as the valve 100 is opened, or as the valve stem 2 is being pulled away from the disc carrier 3, the tapered surface 24 on the valve stem 2 tries to come up through the internal diameter of the retaining ring 5, thus forcing the retaining ring 5 radially outward, further into the carrier groove 22. This creates a wedging force between the retaining ring 5 and the carrier groove 22 that further prevents removal of the valve stem 2 from the stem socket 13.

Accordingly, an extremely strong joint is created. For the joint to come apart under these circumstances, either the carrier groove 22 of the disc carrier 3, or the retaining ring 5 would have to shear, and thus a permanent joint is created that can only be separated by destructive force.

Accordingly, when the stem/carrier assembly 200 is in the open position (i.e. , the valve 100 is in the open position) as described above, the disc carrier 3 is off the valve seat 1 and is exposed to the fluid media flow through the valve body 300. Due to the operation of the resilient member 6, the tapered surface 24 and the retaining ring 5, as described above, the tension created between the valve stem 2, retaining ring 5 and disc carrier 3 prevents rotation of the disc carrier 3 relative to the valve stem 2 that may otherwise be caused by the pressure forces of the fluid media flow through the valve 100.

The method may also include, at step 314, moving the stem/carrier assembly 200 to the closed position. When the stem/carrier assembly 200 is in the closed position, the resilient member 6 is compressed and the force on the stem groove 4 and the retaining ring 5 against the carrier groove 22 is relieved, such that the valve stem 2 may rotate or pivot relative to the disc carrier 3. As the resilient member 6 is compressed, the curvilinear surface 10a of the valve stem 2 makes contact with the conical surface 12a of the stem socket 13, allowing the disc carrier 3 to pivot freely and align perfectly with the face of the valve body seat 1 for tight sealing. The contact area due to the curved shaped interface between the curvilinear surface 10 and the conical surface 12a creates a minimal area of contact, and thus highly concentrated closing forces, while simultaneously maintaining low frictional forces between the valve stem 2 and disc carrier 3. This allows the valve stem 2 to turn or pivot relative to the disc carrier 3 without commensurate rotation of the disc carrier 3 against the face of the valve body seat 1 , which otherwise could potentially cause damage.

In an embodiment, the the valve stem includes a stem groove circumscribing an outer periphery of the socket end of the valve stem. The disc carrier includes a carrier groove circumscribing an inner periphery of the stem socket. The

stem/carrier assembly further includes a retaining ring disposed in the stem groove and the carrier groove.

In another embodiment, the face of the socket end of the valve stem further includes a flat surface circumscribing the curvilinear surface and the terminal face of the stem socket includes a flat surface circumscribing the conical surface. The stem/carrier assembly further includes a resilient member disposed between the flat surface of the socket end of the valve stem and the flat surface of the terminal face of the stem socket. When the stem/carrier assembly is in the open position, the resilient member is expanded and creates a force on the stem groove and the retaining ring against the carrier groove such that the disc carrier does not rotate relative to the valve stem when the stem/carrier assembly is in the open position. When the stem/carrier assembly is in the closed position, the resilient member is compressed and relieves the force on the stem groove and the retaining ring against the carrier groove such that the valve stem may rotate relative to the disc carrier when the stem/carrier assembly is in the closed position.

In another embodiment, the stem groove includes a tapered surface on a side nearest the face of the socket end of the valve stem such that when the stem/carrier assembly is in the open position, the tapered surface of the stem groove is configured to force the retaining ring further into the carrier groove to prevent separation of the valve stem from the disc carrier.

In another embodiment, the disc carrier includes a lead chamfer on the stem- receiving end. In another embodiment, the stem/carrier assembly further includes a sealing disc disposed on the valve seat end of the disc carrier for sealing against the valve seat of the valve body of the refrigeration valve when the stem/carrier assembly is in the closed position. The stem/carrier assembly also further includes a sealing disc retainer for retaining the sealing disc on the valve seat end of the disc carrier.

In another embodiment, the sealing disc retainer includes a sealing disc retaining ring and a washer.

In another embodiment, the resilient member is a wave spring.

In another embodiment, the curvilinear surface of the face of the socket end of the valve stem is convex and the conical surface of the terminal face of the stem socket is concave.

In another embodiment, the refrigeration valve further includes a bonnet disposed on the valve body wherein the bonnet circumscribes the actuator end of the valve stem, and a packing nut disposed between the bonnet and the actuator end of the valve stem.

In another embodiment, the refrigeration valve further includes a gasket for sealing the bonnet against the valve body.

In an embodiment, the valve stem includes a stem groove circumscribing an outer periphery of the socket end of the valve stem, and the disc carrier includes a carrier groove circumscribing an inner periphery of the stem socket. The

In another embodiment, the stem groove includes a tapered surface on a side nearest the face of the socket end of the valve stem such that when the stem/carrier assembly is in the open position, the tapered surface of the stem groove is

configured to force the retaining ring further into the carrier groove to prevent separation of the valve stem from the disc carrier.

In another embodiment, the disc carrier includes a lead chamfer on the stem- receiving end.

In another embodiment, the stem/carrier assembly further includes a sealing disc disposed on the valve seat end of the disc carrier for sealing against a valve seat of the refrigeration valve when the stem/carrier assembly is in the closed position. The stem/carrier assembly also further includes a sealing disc retainer for retaining the sealing disc on the valve seat end of the disc carrier.

In another embodiment, the resilient member is a wave spring.

Yet another aspect of the invention is a method of operating a stem/carrier assembly for a refrigeration valve. The method includes providing a valve stem having an actuator end, a socket end, and a stem groove circumscribing an outer periphery of the socket end, and providing a disc carrier having a valve seat end, a stem-receiving end defining a stem socket, and a carrier groove circumscribing an inner periphery of the stem socket. The method also includes disposing a resilient member within the stem socket of the disc carrier and positioning a retaining ring on the valve stem in a starting position circumscribing the socket end of the valve stem. The method then includes inserting the socket end of the valve stem into the stem socket of the disc carrier such that the retaining ring is pushed into the stem groove, and further inserting the socket end of the valve stem into the stem socket of the disc carrier such that the stem groove aligns with the carrier groove and the retaining ring moves to a secured position. When in the secured position, the retaining ring is disposed in the stem groove and the carrier groove. The stem/carrier assembly is moveable between an open position and a closed position to regulate fluid flow within the refrigeration valve.

In an embodiment, the disposing includes disposing the resilient member on a flat surface of a terminal face of the stem socket and the inserting includes inserting the socket end of the valve stem into the stem socket such that a flat surface of a face of the socket end of the valve stem contacts the resilient member in the stem socket.

In another embodiment, the disc carrier includes a lead chamfer on the stem- receiving end for pushing the retaining ring into the stem groove during the inserting.

In another embodiment, the method further includes moving the stem/carrier assembly to the open position. When the stem/carrier assembly is in the open position, the resilient member is expanded and creates a force on the stem groove and the retaining ring against the carrier groove such that the disc carrier does not rotate relative to the valve stem when the stem/carrier assembly is in the open position.

In another embodiment, the stem groove includes a tapered surface on a side nearest the face of the socket end of the valve stem and when the stem/carrier assembly is in the open position, the tapered surface of the stem groove forces the retaining ring further into the carrier groove to prevent separation of the valve stem from the disc carrier.

In another embodiment, the method further includes moving the stem/carrier assembly to the closed position. When the stem/carrier assembly is in the closed position, the resilient member is compressed and relieves the force on the stem groove and the retaining ring against the carrier groove such that the valve stem may rotate relative to the disc carrier when the stem/carrier assembly is in the closed position.

In another embodiment, when the stem/carrier assembly is in the closed position, a curvilinear surface of the face of the socket end of the valve stem cooperatively engages with a conical surface of the terminal face of the stem socket to allow relative movement of the valve stem relative to the disc carrier.

In another embodiment, the resilient member is a wave spring.

Although the invention has been shown and described with respect to a certain embodiment or embodiments, it is obvious that equivalent alterations and modifications will occur to others skilled in the art upon the reading and

understanding of this specification and the annexed drawings. In particular regard to the various functions performed by the above described elements (components, assemblies, devices, compositions, etc.), the terms (including a reference to a "means") used to describe such elements are intended to correspond, unless otherwise indicated, to any element which performs the specified function of the described element (i.e. , that is functionally equivalent), even though not structurally equivalent to the disclosed structure which performs the function in the herein illustrated exemplary embodiment or embodiments of the invention. In addition, while a particular feature of the invention may have been described above with respect to only one or more of several illustrated embodiments, such feature may be combined with one or more other features of the other embodiments, as may be desired and advantageous for any given or particular application.

Claims

Claims What is claimed is:

1. A refrigeration valve comprising:

a valve body having a valve seat, and

a stem/carrier assembly moveable between an open position and a closed position within the refrigeration valve, the stem/carrier assembly comprising:

a valve stem having an actuator end and a socket end, wherein a face of the socket end comprises a curvilinear surface, and

a disc carrier having a stem-receiving end and a valve seat end, the stem-receiving end defining a stem socket for receiving the socket end of the valve stem, wherein a terminal face of the stem socket comprises a conical surface for cooperative engagement with the curvilinear surface of the socket end of the valve stem to allow relative movement of the valve stem relative to the disc carrier when the stem/carrier assembly is in the closed position.

2. The refrigeration valve of claim 1 wherein the valve stem comprises a stem groove circumscribing an outer periphery of the socket end of the valve stem, and the disc carrier comprises a carrier groove circumscribing an inner periphery of the stem socket, the stem/carrier assembly further comprising:

a retaining ring disposed in the stem groove and the carrier groove.

3. The refrigeration valve of claim 2 wherein the face of the socket end of the valve stem further comprises a flat surface circumscribing the curvilinear surface and the terminal face of the stem socket comprises a flat surface circumscribing the conical surface, the stem/carrier assembly further comprising:

a resilient member disposed between the flat surface of the socket end of the valve stem and the flat surface of the terminal face of the stem socket,

wherein when the stem/carrier assembly is in the open position, the resilient member is expanded and creates a force on the stem groove and the retaining ring against the carrier groove such that the disc carrier does not rotate relative to the valve stem when the stem/carrier assembly is in the open position, and wherein when the stem/carrier assembly is in the closed position, the resilient member is compressed and relieves the force on the stem groove and the retaining ring against the carrier groove such that the valve stem may rotate relative to the disc carrier when the stem/carrier assembly is in the closed position.

4. The refrigeration valve of any of claims 2-3, wherein the stem groove comprises a tapered surface on a side nearest the face of the socket end of the valve stem such that when the stem/carrier assembly is in the open position, the tapered surface of the stem groove is configured to force the retaining ring further into the carrier groove to prevent separation of the valve stem from the disc carrier.

5. The refrigeration valve of any of claims 1 -4, wherein the disc carrier comprises a lead chamfer on the stem -receiving end.

6. The refrigeration valve of any of claims 1 -5, wherein the stem/carrier assembly further comprises:

a sealing disc disposed on the valve seat end of the disc carrier for sealing against the valve seat of the valve body of the refrigeration valve when the stem/carrier assembly is in the closed position, and

a sealing disc retainer for retaining the sealing disc on the valve seat end of the disc carrier.

7. The refrigeration valve of claim 6 wherein the sealing disc retainer comprises: a sealing disc retaining ring, and

a washer.

8. The refrigeration valve of any of claims 3-7 wherein the resilient member is a wave spring.

9. The refrigeration valve of any of claims 1 -8 wherein the curvilinear surface of the face of the socket end of the valve stem is convex and the conical surface of the terminal face of the stem socket is concave.

10. The refrigeration valve of any of claims 1 -9 further comprising: a bonnet disposed on the valve body wherein the bonnet circumscribes the actuator end of the valve stem, and

a packing nut disposed between the bonnet and the actuator end of the valve stem.

11. The refrigeration valve of claim 10 further comprising a gasket for sealing the bonnet against the valve body.

12. A stem/carrier assembly moveable between an open position and a closed position within a refrigeration valve, the assembly comprising:

a disc carrier having a stem-receiving end and a valve seat end, the stem- receiving end defining a socket for receiving the socket end of the valve stem, wherein a terminal face of the stem socket comprises a conical surface for cooperative engagement with the curvilinear surface of the socket end of the valve stem to allow relative movement of the valve stem relative to the disc carrier when the stem/carrier assembly is in the closed position.

13. The stem/carrier assembly of claim 12 wherein the valve stem comprises a stem groove circumscribing an outer periphery of the socket end of the valve stem, and the disc carrier comprises a carrier groove circumscribing an inner periphery of the stem socket, the stem/carrier assembly further comprising:

a retaining ring disposed in the stem groove and the carrier groove.

14. The stem/carrier assembly of claim 13 wherein the face of the socket end of the valve stem further comprises a flat surface circumscribing the curvilinear surface and the terminal face of the stem socket comprises a flat surface circumscribing the conical surface, the stem/carrier assembly further comprising:

wherein when the stem/carrier assembly is in the open position, the resilient member is expanded and creates a force on the stem groove and the retaining ring against the carrier groove such that the disc carrier does not rotate relative to the valve stem when the stem/carrier assembly is in the open position, and

wherein when the stem/carrier assembly is in the closed position, the resilient member is compressed and relieves the force on the stem groove and the retaining ring against the carrier groove such that the valve stem may rotate relative to the disc carrier when the stem/carrier assembly is in the closed position.

15. The stem/carrier assembly of any of claims 13-14, wherein the stem groove comprises a tapered surface on a side nearest the face of the socket end of the valve stem such that when the stem/carrier assembly is in the open position, the tapered surface of the stem groove is configured to force the retaining ring further into the carrier groove to prevent separation of the valve stem from the disc carrier.

16. The stem/carrier assembly of any of claims 12-15, wherein the disc carrier comprises a lead chamfer on the stem -receiving end.

17. The stem/carrier assembly of any of claims 12-16, further comprising:

a sealing disc disposed on the valve seat end of the disc carrier for sealing against a valve seat of the refrigeration valve when the stem/carrier assembly is in the closed position, and

18. The stem/carrier assembly of claim 17 wherein the sealing disc retainer comprises:

a sealing disc retaining ring, and

a washer.

19. The stem/carrier assembly of any of claims 14-18 wherein the resilient member is a wave spring.

20. The stem/carrier assembly of any of claims 12-19 wherein the curvilinear surface of the face of the socket end of the valve stem is convex and the conical surface of the terminal face of the stem socket is concave.

21. A method of operating a stem/carrier assembly for a refrigeration valve comprising:

providing a valve stem having an actuator end, a socket end, and a stem groove circumscribing an outer periphery of the socket end,

providing a disc carrier having a valve seat end, a stem-receiving end defining a stem socket, and a carrier groove circumscribing an inner periphery of the stem socket,

disposing a resilient member within the stem socket of the disc carrier, positioning a retaining ring on the valve stem in a starting position

circumscribing the socket end of the valve stem,

inserting the socket end of the valve stem into the stem socket of the disc carrier such that the retaining ring is pushed into the stem groove, and

further inserting the socket end of the valve stem into the stem socket of the disc carrier such that the stem groove aligns with the carrier groove and the retaining ring moves to a secured position, wherein when in the secured position, the retaining ring is disposed in the stem groove and the carrier groove,

wherein the stem/carrier assembly is moveable between an open position and a closed position to regulate fluid flow within the refrigeration valve.

22. The method of claim 21 wherein the disposing comprises disposing the resilient member on a flat surface of a terminal face of the stem socket and the inserting comprises inserting the socket end of the valve stem into the stem socket such that a flat surface of a face of the socket end of the valve stem contacts the resilient member in the stem socket.

23. The method of any of claims 21 -22 wherein the disc carrier comprises a lead chamfer on the stem -receiving end for pushing the retaining ring into the stem groove during the inserting.

24. The method of any of claims 21 -23, further comprising moving the

stem/carrier assembly to the open position,

wherein when the stem/carrier assembly is in the open position, the resilient member is expanded and creates a force on the stem groove and the retaining ring against the carrier groove such that the disc carrier does not rotate relative to the valve stem when the stem/carrier assembly is in the open position.

25. The method of claim 24 wherein the stem groove comprises a tapered surface on a side nearest the face of the socket end of the valve stem and wherein when the stem/carrier assembly is in the open position, the tapered surface of the stem groove forces the retaining ring further into the carrier groove to prevent separation of the valve stem from the disc carrier.

26. The method of any of claims 24-25, further comprising moving the

stem/carrier assembly to the closed position,

27. The method of claim 26 wherein when the stem/carrier assembly is in the closed position, a curvilinear surface of the face of the socket end of the valve stem cooperatively engages with a conical surface of the terminal face of the stem socket to allow relative movement of the valve stem relative to the disc carrier.

28. The method of claim 27 wherein the curvilinear surface of the face of the socket end of the valve stem is convex and the conical surface of the terminal face of the stem socket is concave.

29. The method of any of claims 21 -28 wherein the resilient member is a wave spring.