The present disclosure generally relates to a dispensing valve. More specifically, the present disclosure relates to a dispensing valve that includes an O-ring retention system to prevent the O-ring from becoming dislodged from a movable valve stem in the dispensing valve.
In a typical construction of dispensing valves, the dispensing valve includes a valve stem that is movable between an open and a closed position. In the closed position, the valve stem prevents the flow of liquid from an inlet to an outlet.
In many dispensing valves, a sealing member, such as an O-ring, is positioned on the valve stem to provide a liquid tight seal between the valve stem and a valve seat when the valve is in a closed position. In applications where the dispensing valve is used with relatively high pressure fluids, the high pressure fluids can force the O-ring off of the valve stem during movement from the closed position to an open position. Therefore, a need exists for a retention system that holds an O-ring on the valve stem during use.
The present disclosure relates to a dispensing valve in which an inexpensive O-ring can be purchased in any number of materials, sizes and durometers. The O-ring forms a face seal with a valve seat when the valve stem is in the closed. condition. Typically, O-rings are not used as face seals since the water pressure acts on the O-ring to force it off of the movable valve stem as the movable valve stem is titled off the valve seat. This is primarily true when higher differential pressures are used.
The present disclosure utilizes a snap-on collar that captures the O-ring between the collar and the valve stem. The snap-on collar prevents the O-ring from lifting off of the valve stem during movement of the valve stem between the open and closed conditions.
The present disclosure further relates to a dispensing valve that includes a valve body having an inlet and an outlet. The dispensing valve includes a valve stem that is movable within the valve body between an open position and a closed position. When the valve stem is in the closed position, the valve stem prevents the flow of liquid from the inlet to the outlet. In the open position, the valve stem allows fluid to flow from the inlet to the outlet.
The dispensing valve further includes an O-ring that is mounted to an outer surface of the valve stem. Specifically, the O-ring is received within a sealing groove that is formed in the valve stem at or near an outer end of the valve stem. The resilient nature of the O-ring holds the O-ring within the sealing groove.
In one embodiment of the disclosure, the dispensing valve includes a bias spring that urges the valve stem toward the closed position. In such an embodiment, the dispensing valve includes an actuator that moves the valve stem against the bias force created by the bias spring toward an open position.
The valve stem includes a retaining collar that is snap tit onto the valve stem. When the retaining collar and O-ring are both mounted to the valve stem, the retaining collar at least partially surrounds the O-ring to hold the O-ring in position on the valve stem. The retaining collar is configured to have a bottom end that is generally aligned with an equator of the O-ring to prevent both expansion of the O-ring and restrict the flow of pressurized liquid between the O-ring and the valve stem.
In one embodiment of the disclosure, the retaining collar is formed from a plastic material. The retaining collar can include one or more slots that allow the top end of the collar to flex outward and create a snap fit of the retaining collar onto the valve stem.
Various other features, objects and advantages of the invention will be made apparent from the following description taken together with the drawings.
The drawings illustrate the best mode presently contemplated of carrying out the disclosure. In the drawings:
a is a section view of the dispensing valve in the open position;
b is as magnified view of the valve stem in the open position;
a is a section view of the dispensing valve in the closed position;
b is a magnified view showing the valve stem in the closed position;
The flow of fluid from the inlet 16 to the outlet 18 is controlled by the position of a movable valve stem 26. The valve stein 26 is biased into the closed position shown in
a and 4b illustrate the valve stem 26 in the closed position. As illustrated best in
As illustrated in
When the valve stem 26 begins to move upward from the closed position of
If the O-ring 38 were used alone on the outer end 43 of the valve stem 26, the high pressure fluid flow may cause the O-ring 38 to become separated from the valve stem 26, which would render the dispensing valve inoperable. To address this issue, the valve stem 26 includes a retention system that includes a retaining collar 46. As illustrated in
As shown in
The section view of
Referring back to
As discussed previously, the bottom end 48 of the collar is generally aligned with the equator 61 of the O-ring 38. Thus, the outer wall 64 of the collar 46 prevents liquid from directly flowing into contact with the O-ring 38 at a location above the equator 61. In addition, due to the close spacing between the inner surface 66 of the outer wall 64 and the outer surface 68 of the O-ring 38, the collar 46 prevents the O-ring 38 from expanding outward. In this way, the collar 46 prevents the dislodgement of the O-ring 38 from the valve stem 26 during movement of the valve stem from the closed position to the open position.
This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to make and use the invention. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.
The present application is based on and claims priority to U.S. Provisional Patent Application Ser. No. 61/901,605 filed Nov. 8, 2013, the disclosure of which is incorporated herein by reference.
Number | Date | Country | |
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61901605 | Nov 2013 | US |