The present invention relates generally to air release valves, and particularly to an air release valve with separation of gas and liquid flow routes.

BACKGROUND OF THE INVENTION

Fluid flow valves which include air release or air purge features are well known. Such valves are typically located in liquid pipes or conduits (such as sewage pipes) and release air or other gases to avoid air or gas locks which otherwise interfere with the flow of liquid through the pipe. (The term air release valve is used interchangeably with the term gas release valve; that is, the valve may be used with any kind of gas or gas mixture.)

A typical air release valve has an orifice (aperture) for the release of 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 forced upwards by the flowing liquid, which seals the float against the outlet orifice. If air accumulates in the conduit, the float moves downwards under its own weight, which opens the outlet orifice to vent air or gas.

In prior art air release valves the gas and liquid flow in the same route. This can lead to some problems. For example, since the gas generally flows quicker than the liquid, the gas stream can lift the float before the liquid has filled the valve. The basic aerodynamic design of the float does not provide a good separation, if at all, between the liquid stream and the gas stream. As a result, there is degradation in the efficiency and performance of the air release valve.

SUMMARY OF THE INVENTION

The present invention seeks to provide an improved air release valve, as is described more in detail hereinbelow. The air release valve of the invention provides separation of gas and liquid flow routes and thus significantly better performance and reliability than valves of the prior art.

There is thus provided in accordance with an embodiment of the present invention an air release valve including a housing which has an inlet and a seal disposed in the housing arranged to seal against an outlet of the housing, and dividing structure that defines a liquid flow path, which leads to a lower portion of the seal, and a gas flow path, which leads to the outlet. The liquid flow path and the gas flow path are separate from one another. BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be understood and appreciated more fully from the following detailed description, taken in conjunction with the drawing in which:

Figs. 1 and 2 are simplified pictorial and sectional illustrations, respectively, of an air release valve, constructed and operative in accordance with a non-limiting embodiment of the present invention;

Figs. 3 and 4 are simplified pictorial and sectional illustrations, respectively, of an air release valve, constructed and operative in accordance with a non-limiting embodiment of the present invention;

Figs. 5 and 6 are simplified pictorial and sectional illustrations, respectively, of an air release valve, constructed and operative in accordance with a non-limiting embodiment of the present invention;

Figs. 7 and 8 are simplified pictorial and sectional illustrations, respectively, of an air release valve, constructed and operative in accordance with a non-limiting embodiment of the present invention;

Figs. 9 and 10 are simplified pictorial and sectional illustrations, respectively, of an air release valve, constructed and operative in accordance with a non-limiting embodiment of the present invention;

Figs. 11 and 12 are simplified cutaway and sectional illustrations, respectively, of an air release valve, constructed and operative in accordance with a non-limiting embodiment of the present invention; and

Figs. 13 and 14 are simplified cutaway and sectional illustrations, respectively, of an air release valve, constructed and operative in accordance with a non-limiting embodiment of the present invention.

DETAIFED DESCRIPTION OF EMBODIMENTS

Reference is now made to Figs. 1 and 2, which illustrate an air release valve 10, constructed and operative in accordance with a non-limiting embodiment of the present invention.

The air release valve 10 includes a housing 11 which has an inlet 12 fluidly connectable to a water line or pipe line (not shown). A buoy or seal 14 is disposed in housing 11. An upper portion 15 of seal 14, which may include an O-ring 16 or other kind of seal or gasket, is arranged to seal against a valve seat 17 on an inner surface of an outlet 18 of housing 11. In accordance with a non-limiting embodiment of the present invention, the inlet 12 is tangential to a first side 7 of housing 11 and the outlet 18 is located at a second side 9 of housing 11, wherein the first side 7 is separated from the second side 9 by a distance in housing 11.

In accordance with a non-limiting embodiment of the present invention, housing

11 includes dividing structure that defines a liquid flow path 19, which leads to a lower portion of seal 14, and a gas flow path 21, which leads to the outlet 18.

In the embodiment of Fig. 2, the dividing structure includes a conduit 22 located between inlet 12 and outlet 18. Conduit 22 may be parallel to inlet 12. Conduit 22 may be open at a lower end thereof facing the lower portion of housing 11. The first side 7 of housing 11 and an outer contour of conduit 22 and a surface 23 of housing opposite inlet

12 define a first chamber 25. A gas vent 24 is provided in conduit 22 near the upper portion of the first chamber 25.

The operation of air release valve 10 is now described. Since the inlet 12 is tangential to the housing 11, the mixture of liquid and gas that enters inlet 11 becomes separated, since the gas can easily flow up the first side 7 while the liquid flows at a lower velocity than the gas; the liquid “seeks its own level” along the lower portion of housing 11 according to the law of communicating vessels. More specifically, after the mixture of liquid and gas enters inlet 12, the liquid flows through the tangential inlet 12 whereas the gas is forced to flow in the gas flow path 21. The gas in the first chamber 25 flows through gas vent 24 into conduit 22 and then flows upwards over the upper portion 15 of seal 14 and exits outlet 18 to complete the gas flow path 21. In the meantime, the liquid flows in liquid flow path 19 along the lower portion of housing 11 to below float 14 (this being called the second chamber) at a reduced velocity. As the liquid in the second chamber rises, the float 14 rises and seals outlet 18. Unlike the prior art, the gas flow cannot lift float 14 before the liquid has filled the valve 10.

Reference is now made to Figs. 3 and 4, which illustrate an air release valve 30, constructed and operative in accordance with another non-limiting embodiment of the present invention. The main differences between air release valve 10 and air release valve 30 include a different location of the gas vent, the float being located in the dividing structure (conduit) and the addition of a liquid drain.

The air release valve 30 includes a housing 31 which has an inlet 32 fluidly connectable to a water line or pipe line (not shown). A buoy or seal 34 is disposed in housing 31. An upper portion 35 of seal 34, which may include an O-ring 36 or other kind of seal or gasket, is arranged to seal against a valve seat 37 on an inner surface of an outlet 38 of housing 31.

The inlet 32 is tangential to a first side 27 of housing 31 and the outlet 38 is in the middle of housing 11. Housing 31 includes dividing structure that defines a liquid flow path 39, which leads to a lower portion of seal 34, and a gas flow path 41, which leads to the outlet 38, wherein the liquid flow path 39 and the gas flow path 41 are separate from one another.

In the embodiment of Fig. 4, the dividing structure includes a conduit 42 in which the seal 34 is placed. Conduit 42 is open at its upper end at outlet 38. A gas vent 44 is provided in conduit 42 on a side opposite to inlet 32. A liquid drain 46 may be provided at a lower portion of housing 31, which can be closed and opened by a suitable valve (not shown).

In the operation of air release valve 30, the mixture of liquid and gas flows through the tangential inlet 32. The gas flows along the gas flow path 41 around conduit 42 at the upper portion of the valve and enters the gas vent 44 and then exits outlet 38. Centrifugal force forces the liquid to flow towards the inner surfaces of the outer walls of the valve 30. The liquid then flows downwards towards the lower portion of housing 31 in the liquid flow path 39 (with the drain closed). As the liquid rises, the float 34 rises and seals outlet 38. Unlike the prior art, the gas flow cannot lift float 34 before the liquid has filled the valve 30.

Reference is now made to Figs. 5 and 6, which illustrate an air release valve 50, constructed and operative in accordance with another non-limiting embodiment of the present invention.

In air release valve 50, as opposed to the previous embodiments, there is an inlet 52 to which is connected a bypass 53. Both the bypass 53 and the inlet 52 are the same diameter. The kinetic energy of the liquid causes the liquid to flow upwards. The gas flow is divided equally between the inlet 52 and the bypass 53. By varying the diameter of the bypass 53, one can control the gas flow rate and control the drag force required to lift the float 54.

In air release valve 50, the bypass 53 is the dividing structure.

Reference is now made to Figs. 7 and 8, which illustrate an air release valve 70, constructed and operative in accordance with another non-limiting embodiment of the present invention. In air release valve 70, as opposed to the previous embodiments, the liquid and gas mixture enters an inlet 72 and flows towards the upper portion of a housing 71. Here the dividing structure is a break wall 75. Upon flowing against the break wall 75, the liquid loses its kinetic energy, which causes the liquid to flow down in the liquid flow path to the lower portion of housing 71 and eventually to the bottom of float 74. The gas flows in the gas flow path to around the break wall 75 to the outlet 78. A liquid drain 76 may be provided.

Reference is now made to Figs. 9 and 10, which illustrate an air release valve 90, constructed and operative in accordance with another non-limiting embodiment of the present invention.

Air release valve 90 is similar to air release valve 70 in that air release valve 90 also includes a break wall 95. In air release valve 90, break wall 95 is formed with one or more apertures 97 for the gas to flow through. The break wall 95 prevents the liquid entering inlet 92 from flowing directly towards the outlet 98 by redirecting the liquid downwards. Gas is free to flow through the one or more apertures 97 at the extremities of the break wall 95. Additionally, the break wall 95 decreases the liquid speed, allowing the float 94 to rise in a more controlled way. As in other embodiments, a liquid drain may be provided for purging the pipeline.

Reference is now made to Figs. 11 and 12, which illustrate an air release valve

110, constructed and operative in accordance with another non-limiting embodiment of the present invention.

Air release valve 110 includes a dome 121 (Fig. 12) underneath float 114, and a break wall 115. Dome 121 breaks most of the liquid flow, that is, it is the main element that diminishes the kinetic energy of the liquid flow. The break wall 115 includes one or more internally protruding rings 117 that protrude inwardly from inner walls of housing

111. Alternatively or additionally, break wall 115 includes one or more outwardly protruding rings 119 that protrude outwardly from a conduit 113 in which float 114 is disposed. Rings 117 and 119 break any liquid that flows around dome 121.

As with the other embodiments, the liquid and gas mixture flows through the inlet 112 and this forces the gas in the pipeline into the valve 110. As the liquid hits the break wall 115, it is dispersed in all directions and the speed of the liquid decreases. This allows the float 114 to rise in a more controlled way. A gas vent 116 may be provided to allow the gas to flow out of the valve 110 above the float 114. The liquid can drain back to the pipeline via the inlet 112 at the bottom. Reference is now made to Figs. 13 and 14, which illustrate an air release valve 130, constructed and operative in accordance with another non-limiting embodiment of the present invention.

Similarly to the embodiment of Figs. 3 and 4, the dividing structure of air release valve 130 includes a conduit 142 in which the seal 134 is placed. Conduit 142 is formed with one or more apertures 143.

As with the other embodiments, the liquid and gas mixture flows through the inlet 132 and this forces the gas in the pipeline into the valve 130. The liquid and gas mixture flows around float 134 until it reaches the aperture or apertures 143 in the conduit 142. The liquid and gas mixture flows through the apertures 143 into the chamber that is between the outer surface of conduit 142 and the inner surface of housing 131. After flowing into this chamber, the gas continues to flow upwards to the outlet 138, whereas the liquid flows downwards by the force of gravity. The liquid can drain back to the pipeline via one or more drain openings 137 towards the inlet 132 at the bottom.