Air release valve with low pressure seal

Abstract

The air release valve (10) includes: a housing (11) fluidly connectable to a water line; a valve seat (12) fixed to a portion of the housing (11) and formed with one or more air outlet channels (14); a seal (18) formed as a spring disk and including a rod (28) slidably engaged with the valve seat (12); and a weight (20) coupled to the seal (18). In a sealed configuration, the seal (18) presses against the valve seat (12) and seals the one or more air outlet channels (14) to prevent air from passing through the one or more air outlet channels, and in an open configuration, the seal (18) is moved by the weight (20) so that the seal (18) does not press against the valve seat (12) and the seal allows air to pass through the one or more air outlet channels (14).

Description

Technical Field

[0001] The present invention relates generally to air release valves and, more particularly, to an air release valve that seals and prevents air from escaping even at low pressures. Background Art

[0002] Fluid flow valves that include an air release or air purge feature are well known. Such valves are typically located in a liquid pipe or conduit (such as a sewage pipe) and release air or other gas to avoid air or gas lock, which would otherwise interfere with the flow of liquid through the pipe. (The term "air release valve" may be used interchangeably with the term "gas release valve"; that is, the valve may be used with any type of gas or gas mixture.)

[0003] A typical air release valve has an orifice (hole) for releasing gas, and the orifice is opened and closed by a float, or alternatively by a linkage mechanism operated by the float. During normal flow conditions, the float is sealingly pressed against the outlet orifice by the flowing liquid. If air accumulates in the conduit, the float moves downward due to its own weight, thereby opening the outlet orifice to discharge the air or gas.

[0004] However, a disadvantage of the prior art air release valve is that it is difficult to seal the outflow (exhaust) of air to the outside atmosphere when the pressure in the water line (plumbing line) is very low. Very low pressure is usually not enough to close the seal in the prior art valve. Summary of the invention

[0005] The present invention seeks to provide an improved air release valve, as described in more detail below. When the pressure in the water line (plumbing line, the terms are used interchangeably) is very low, even when there is almost zero relative pressure (pressure in the line relative to atmospheric pressure), the valve of the present invention seals and stops the flow of air to the outside. The air release valve of the present invention is thus significantly more reliable than the valves of the prior art.

[0006] Thus, according to an embodiment of the present invention, an air release valve is provided, which includes: a housing, which is capable of being fluidly connected to a water pipeline; a valve seat, which is fixed to a portion of the housing and has one or more air outlet channels formed therein; a seal, which is formed as a spring disk and includes a rod slidably engaged with the valve seat; and a weight, which is connected to the seal, wherein in a sealed configuration, the seal presses against the valve seat and the seal seals the one or more air outlet channels to prevent air from passing through the one or more air outlet channels, and in an open configuration, the seal is moved by the weight so that the seal does not press against the valve seat and the seal allows air to pass through the one or more air outlet channels.

[0007] The seal may include an attachment structure attached to the weight. The attachment structure may include two or more arcuate arms having fasteners that are secured in slots formed in the weight.

[0008] The seal stem may be received in a bore formed in the valve seat. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The present invention will be more fully understood and appreciated from the following detailed description taken in conjunction with the accompanying drawings, in which:

[0010] Figure 1 is a simplified cross-sectional view of an air release valve constructed and operative in accordance with a non-limiting embodiment of the present invention;

[0011] Figure 2 is an enlarged cross-sectional view of the air release valve;

[0012] Figure 3A and Figure 3B is a simplified diagrammatic illustration of the weight (float), seal, and seat components of an air release valve;

[0013] Figure 4 is a simplified diagram of the valve seat showing the air outlet passage; and

[0014] Figure 5 is a simplified illustration of a seal having an attachment structure to a weight and a seal stem coupled to a valve seat according to a non-limiting embodiment of the present invention. DETAILED DESCRIPTION

[0015] Reference now Figure 1 and Figure 2 , Figure 1 and Figure 2 An air release valve 10 is shown, constructed and operative in accordance with a non-limiting embodiment of the present invention.

[0016] As is known in the art, air release valve 10 includes a housing 11 that is fluidly connectable to a water line or plumbing line (not shown). A valve seat 12 is secured to a portion (typically an upper portion) of housing 11, such as by a cap 13 that clamps down on valve seat 12. Cap 13 is sealingly attached to housing 11, for example, by a threaded connection or by a tight O-ring fit. Housing 11 has an inlet 5 and an outlet 6.

[0017] The valve seat 12 is formed with one or more air outlet passages 14 (in the illustrated embodiment there are two diametrically opposed elongated passages, i.e. two passages on opposite sides of the central axis of the valve seat 12). Figure 2 and Figure 3A As shown in , the valve seat 12 may be conical such that it is thicker in the center and tapers in the radially outward direction. The air outlet passage 14 may be formed in the thicker center portion of the valve seat 12, but may alternatively be formed at other locations in the valve seat.

[0018] The air release valve 10 includes a seal 18, which is made of an elastomeric material and is formed as a Belleville washer or an umbrella seal, i.e., a spring disk or a conical spring disk, etc., all of which terms are used interchangeably. The seal 18 is coupled to a weight 20, which may also be referred to as a float. The weight 20 may be made of any suitable material such as metal or plastic.

[0019] like Figure 2 As shown in FIG. 1 , the seal 18 includes an attachment structure 22 that is attached to a weight 20. For example, as shown in FIG. Figure 5 As best shown in FIG. 1 , the attachment structure 22 may be two or more arcuate arms 23 having push-fit (eg, cylindrical) fasteners 24 that are secured within slots 26 (eg, formed in the weight 20) and slits 26 (eg, cylindrical) formed in the weight 20. Figure 2 ). The seal 18 also includes a seal rod 28, such as Figure 2 , the seal stem 28 is received in a hole 30 formed in a central portion 31 of the valve seat 12. The seal stem 28 may be formed with a radially enlarged protrusion 32 that can seat on a countersunk hole 34 formed in the hole 30. In this way, the seal stem 28 cannot fall through the valve seat 12.

[0020] The operation of the air release valve 10 is now described. In the first case, there is little or no water in the water line. In this case, the weight 20 is in a low position away from the valve seat 12, and the seal 18 moves downward with the weight 20 only by gravity. As described above, the seal 18 and the weight 20 are held in place by the seal rod 28 resting on the "shelf" of the countersunk hole 34. In this position, the seal 18 is not pressed against the valve seat 12, so the air outlet passage 14 is not blocked and air can flow through the air outlet passage 14 from the inlet 5 toward the outlet 6.

[0021] In the second case, water enters the inlet 5 and lifts the weight 20 to Figure 1 and Figure 2 In this position, the seal 18 presses against the valve seat 12, thereby sealing the air outlet channel 14 so that air cannot flow through the air outlet channel 14. The air flow from the inlet 5 toward the outlet 6 is stopped. The valve of the present invention seals and stops the outward flow of air even at very low pressures in the water line or even at almost zero relative pressure.

[0022] In the third case, when the water level drops slightly, the seal 18 is pulled downwards by the weight 20, thereby opening the air outlet channel 14 again and air flows out of the outlet 6. This occurs even at very low pressure differences, so the air release valve 10 is a very sensitive device.

[0023] It should be noted that the seal rod 28 is capable of sealing against the base of the countersunk hole 34 (eg, Figure 2 41 in the figure), and the base of the sealing rod 28 is capable of sealing against the central portion 31 of the valve seat 12 (as shown in FIG. Figure 2 43 in the figure).

Claims

1. An air release valve (10), comprising: a housing (11) capable of being fluidly connected to a water line; a valve seat (12) fixed to a portion of the housing (11) and formed with one or more air outlet passages (14); a seal (18) formed as a spring disk and comprising a seal stem (28) slidably engaged with the valve seat (12); and a weight (20) coupled to the seal (18), wherein in a sealed configuration, the seal (18) presses against the valve seat (12) and the seal (18) seals the one or more air outlet channels (14) to prevent air from passing through the one or more air outlet channels (14), and in an open configuration, the seal (18) is moved by the weight (20) so that the seal (18) does not press against the valve seat (12) and the seal (18) allows air to pass through the one or more air outlet channels (14), wherein the seal (18) includes an attachment structure (22) attached to the weight (20), and The attachment structure (22) includes two or more arcuate arms (23), the two or more arcuate arms having fasteners (24), and the fasteners (24) are fixed in gaps (26) formed in the weight (20).

2. The air release valve (10) of claim 1, wherein the seal stem (28) is received in a hole (30) formed in the valve seat (12).

3. The air release valve (10) of claim 2, wherein the seal stem (28) is formed with a radially enlarged protrusion (32) that is received in a countersunk hole (34) formed in the bore (30).

4. The air release valve (10) of claim 1, wherein the one or more air outlet passages (14) comprise a pair of diametrically opposed elongated passages.

5. The air release valve (10) according to claim 1, wherein the valve seat (12) is conical such that the valve seat (12) is thicker in a central portion of the valve seat (12) and gradually narrows in a radially outward direction.

6. The air release valve (10) of claim 3, wherein the seal stem (28) is arranged to seal against a base of the countersunk hole (34).

7. The air release valve (10) according to claim 1, wherein the seal stem (28) is arranged to seal against a central portion (31) of the valve seat (12).

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