HK1240304B - Deluge valve with valve seat drain - Google Patents

Description

Deluge valve with seat drain

Technical field and prior art

The present invention relates to valves and, in particular, the present invention is concerned with deluge valves having a seat drain.

It is known to provide a valve, commonly referred to as a "deluge valve," for applications such as a sprinkler fire extinguishing system to seal and selectively open a flow path from a water-filled inlet to a dry outlet. The deluge valve is a normally closed valve that prevents water flow until the sprinkler system is activated.

In many systems, the deluge valve forms a barrier between an upstream fill pipe and dry downstream piping leading to the sprinklers. This implementation is particularly advantageous in situations where the sprinkler system may be exposed to low temperatures, posing a risk of blockage due to freezing of the fill pipe. Where the downstream piping must remain dry, a deluge valve releasing even a small amount of water into the outlet pipe is considered unacceptable. Furthermore, deluge valve reliability issues arise when minor leaks occur, leading to inconvenient and costly maintenance.

Summary of the Invention

The present invention is a valve for sealing and selectively opening a flow path from a water filling inlet to a drying outlet.

According to the teachings of the present invention, a valve is provided for sealing and selectively opening a flow path from a water-filled inlet to a dry outlet, the valve comprising: (a) a valve body having a valve opening and a second annular valve seat area, the valve opening being surrounded by a first annular valve seat area, the second annular valve seat area surrounding the first annular valve seat area; the valve body including at least one drainage channel, the drainage channel being fluidically connected to a space between the first annular valve seat area and the second annular valve seat area, the drainage channel providing a fluid drainage path to the exterior of the valve body; and, (b) a plug having an open state and a closed state for closing the valve opening. The plug is displaceable between two states, the plug having a first annular sealing ring and a second annular sealing ring, the first annular sealing ring being configured to seal the first annular valve seat area, and the second annular sealing ring being configured to seal the second annular valve seat area, wherein the second annular sealing ring is an elastic sealing ring, and the second annular sealing ring is configured so that during the displacement of the plug from the open state to the closed state, before the contact between the first annular sealing ring and the first annular valve seat area, the second annular sealing ring is in close contact with the second annular valve seat area; when the plug reaches the closed state, the second annular sealing ring is elastically deformed so as to be pressed into contact with the second annular valve seat.

According to a further feature of an embodiment of the present invention, the second annular sealing ring has an outwardly flared edge, and the outwardly flared edge is configured so that the pressure difference between the outlet pressure at the outlet and the drainage pressure in the drainage channel serves to enhance the sealing of the second annular sealing ring on the second annular valve seat area.

According to a further feature of an embodiment of the present invention, the plug is associated with a flexible diaphragm, and the valve further includes a cover body, the cover body cooperating with the diaphragm to define a control chamber between the diaphragm and the cover body.

According to a further feature of an embodiment of the present invention, the plug, the diaphragm, the valve body, and the cover are configured so that when the pressure in the control chamber is equal to the inlet pressure, a net closing force acts to force the first annular sealing ring against the first annular valve seat area.

According to a further feature of an embodiment of the invention, the plug and the diaphragm are configured so that the closing force of the second annular seal on the second annular valve seat area varies as a function of at least one pressure differential between the control chamber and the drain passage.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention is herein described, by way of example only, with reference to the accompanying drawings, in which:

FIG1 is an isometric view of an automatic hydraulic deluge valve according to one embodiment of the present invention;

2A and 2B are cross-sectional views of the automatic hydraulic deluge valve shown in FIG. 1 , showing a plug in a closed state and an open state, respectively;

FIG3 is a top view of a valve body after the valve shown in FIG1 is cut away along the line III-III in FIG2A;

FIG4A is a cross-sectional view similar to FIG2 , marking various regions of a plug-diaphragm assembly of the valve, with pressure within the control chamber being applied to the plug-diaphragm assembly;

FIG4B is an enlarged view of an area in FIG4A ;

FIG5A is a further diagram of an area in FIG4B , showing a continuous state of deformation of an area of the plug when the plug is in close contact with the valve seat;

FIG5B is similar to FIG5A and is a cross-sectional view showing a modified embodiment of a double seal and valve seat;

FIG6 is similar to FIG5A and is a cross-sectional view showing an alternative configuration of the valve seat;

FIG7A is similar to FIG3 and is a top view of a valve body according to the optional valve seat configuration shown in FIG6 ;

FIG7B is a partial view similar to FIG3, illustrating an alternative form of a drain opening of the valve body; and,

FIG. 8 is a cross-sectional view similar to FIG. 4B , illustrating an alternative embodiment of the present invention.

DETAILED DESCRIPTION

The present invention is a valve for sealing and selectively opening a flow path from a water filling inlet to a drying outlet.

The principle and operation of the valve of the present invention may be better understood with reference to the accompanying drawings and accompanying descriptions.

Referring to the drawings, Figures 1 through 8 illustrate a valve, generally designated 10, constructed and operative in accordance with one embodiment of the present invention for sealing and selectively opening a flow path from a water-filled inlet (upstream port) 210 to a dry outlet (downstream port) 220. Generally speaking, valve 10 comprises a valve body 100 having a valve opening (seat aperture) 230 and a second annular valve seat region 120. Valve opening 230 is surrounded by a first annular valve seat region 110, which in turn surrounds the first annular valve seat region 110. Valve body 100 includes at least one drain passage, shown here as drain opening 510, fluidly connected to the space between first and second annular valve seat regions 110, 120. The drain passage provides a fluid drainage path, typically through a drain conduit 500, to the exterior of valve body 100. A plug 300 is displaceable between an open position ( FIG. 2B ) and a closed position ( FIG. 2A ) for closing the valve opening 230. The plug 300 has a first annular sealing ring 310 configured to seal the first annular valve seat area 110 and a second annular sealing ring 350 configured to seal the second annular valve seat area 120. The second annular sealing ring 350 is implemented as an elastic sealing ring and is configured such that, during displacement of the plug from the open position to the closed position, the second annular sealing ring 350 abuts the second annular valve seat area 120 before contact between the first annular sealing ring 310 and the first annular valve seat area 110. When the plug 300 reaches the closed position, as the first annular sealing ring 310 seals against the first annular valve seat area 110, the second annular sealing ring 350 elastically deforms, thereby being pressed into contact with the second annular valve seat 120.

In the above arrangement, an external seal closes before the plug 300 completes its closing action, and drainage is provided by the space between the two sealing rings. This arrangement significantly enhances protection against accidental water leakage from the inlet 210 to the outlet 220. Specifically, if the plug 300 is momentarily lifted slightly by an inlet pressure spike, this opening is typically insufficient to affect the second sealing ring. When the plug returns to its normal sealing position, water trapped between the sealing rings drains through the drain opening 510 without reaching the downstream pipe. Similarly, dirt or debris that could become lodged within the first sealing ring and cause a slow leak will simply cause water to penetrate the space between the sealing rings and drain from there through the drain opening 510 without reaching the downstream pipe. These and other advantages of the present invention will be further understood with reference to the following figures and description.

As a primary example of an application suitable for the present invention, water is cited herein as the pressurized fluid and a sprinkler system as the downstream destination of the water. It will be appreciated that the present invention itself is not limited to this application and may also be found effective in a variety of other applications in which a valve defines the dividing line between a filled length of a pipe and a dry length of the pipe.

Turning now to a more detailed description of the features of certain preferred embodiments of the present invention, the second annular seal ring 350 can advantageously be implemented as a flared edge (also referred to as a "check lip") configured such that a pressure differential between an outlet pressure at the outlet 220 and a drain pressure within the drain passage 500 acts to enhance the seal of the second annular seal ring 350 against the second annular valve seat area 120. The word "flared" herein refers to a structure that extends outwardly when extending downwardly, corresponding to the fact that the edge of the seal ring 350 extends outwardly and downwardly from the plug. In the primary embodiment described herein, the edge extends downwardly to a level below that of the first annular seal ring 310 in the relaxed state, thereby ensuring that the seal ring 350 contacts the second annular valve seat area 120 before the first annular seal ring 310 closes when the two valve seat areas are in a common plane. In other cases where the valve seat is stepped or otherwise contoured, the desired closing sequence may be achieved even if the sealing ring 350 is at the same level as the first annular sealing ring 310, or in some cases higher than the first annular sealing ring 310.

The use of a flared rim as at least a portion of the sealing ring 350 serves various purposes. First, the rim is preferably formed of an elastomeric material and contributes to the flexibility of the sealing ring 350, allowing it to close before the plug reaches its closed end position and then to absorb the remaining movement through elastic deformation. The flexibility of the rim is preferably enhanced by providing an annular groove 330 on the lower surface of the plug at the base of the rim. This groove also helps to form a continuous channel around the periphery of the first annular sealing ring 310, which allows water to pass between the sealing rings, thereby allowing the water to reach the drain opening 510.

Another preferred function of the rim is to utilize back pressure from the outlet conduit to enhance the valve's seal. The dry air supply conduit of a sprinkler system is typically maintained at a slightly elevated pressure, allowing a drop in pressure to detect the opening of a sprinkler head in the system. This pressure acts on the upper side of the rim, while the lower side is exposed to atmospheric pressure through the drain conduit 500 and opening 510. This pressure differential further enhances the contact force of the rim against the second annular valve seat area 120, further enhancing the seal.

As described herein, certain particularly preferred embodiments of the present invention are hydraulic control valves in which valve closure is achieved and maintained by pressure within a control chamber. In the preferred embodiment described herein, a plug 300 is associated with a flexible diaphragm 400. Diaphragm 400 may be attached to plug 300 or, as shown here, may be integral with the plug, with the majority of plug 300 formed from an elastomeric material. When formed from an elastomer, the body of plug 300 is preferably sized to be relatively inflexible in order to reliably perform its sealing function against valve seat aperture 230. Additionally, or alternatively, additional rigidity may be optionally imparted to the body of plug 300 by including a rigid inner core 308 (metallic, ceramic, or other) within the elastomer. Preferably, the periphery of the diaphragm 400 is fixed between the valve body 100 and the cover 200, for example by a peripheral thickened section 452, which engages and seals a corresponding channel formed between the cover and the valve body.

The valve 10 also includes a housing 200 that cooperates with the diaphragm 400 to define a control chamber 250 between the diaphragm 400 and the housing 200. Most preferably, the plug 300, diaphragm 400, valve body 100, and housing 200 are configured such that when the pressure within the control chamber equals the pressure at the inlet, a net closing force acts to force the first annular sealing ring against the first annular valve seat area. The balance of surface areas upon which the inlet pressure acts to achieve this result is discussed further below. This allows for a particularly simple control configuration, as schematically illustrated in Figures 2A and 2B. As shown in Figure 2A, in the normally closed state of the valve 10, pressure from the high-pressure feedwater 260 is transferred to a control chamber port 264 via a pilot valve 262. In this state, the pressures acting on the diaphragm within the inlet 210 and the control chamber 250 are equal. As described in detail below, this equal pressure exerts a net closing force on the plug 300. When the pilot valve 262 is switched to the state of FIG. 2B , the pressure in the control chamber 250 is disconnected from the high-pressure water supply 260 and the control chamber 250 is opened to drain water at atmospheric pressure, which allows the inlet pressure to act on the lower surface of the plug 300 and displace the plug 300 toward the open position of FIG. 2B .

Another particularly preferred feature of certain embodiments of the present invention is that the closing force exerted by the second annular sealing ring 350 on the second annular valve seat region 120 varies as a function of at least one pressure differential between the control chamber 250 and the drain opening 510. Specifically, in the particularly preferred but non-limiting embodiment of Figures 2A to 4B, a continuous peripheral portion 302 of elastomeric material extends around the plug 300 to form a continuous bridge between an upper peripheral portion 304 of the plug 300 located at the root of the diaphragm 400 and the second annular sealing ring 350. The peripheral portion 302 undergoes shear deformation in response to the pressure differential between the upper peripheral portion 304 and the pressure within the annular channel 330 (atmospheric pressure), thereby increasing the contact pressure of the sealing ring 350 and causing the sealing ring 350 to conform more closely to the second annular valve seat region 120. Optionally, an upper annular groove 306 extends around the plug 300 only within the root of the diaphragm 400, helping to reduce the peripheral portion 302's resistance to shear deformation and thereby enhancing the function of the sealing ring 350 as a standalone sealing ring. In certain embodiments (not shown), annular grooves 330 and 306 may be implemented as deeper grooves extending from opposing top/bottom sides of plug 350 , thereby further increasing axial mobility of peripheral portion 302 relative to the main portion of plug 350 .

The drain opening 510 and drain conduit 500 are used to drain any small amount of water that penetrates the seal of the first valve seat 110 into the atmospheric pressure area between the two seals, thereby releasing the water through a drain port 520. The seal of the second valve seat 120 prevents water from entering the dry pipe of the sprinkler system and prevents compressed air from flowing back into the drain opening. Optionally, the drain port 520 can be connected to an alarm system (not shown) so that when the valve 10 is opened, the water discharged through the drain opening 510 can effectively activate an alarm.

Figures 4A and 4B illustrate different areas of the plug 300 and diaphragm 400 on which the hydraulic pressure within the valve exerts forces. In the normally closed state of Figure 2A , as described above, the pressure within the control chamber 250 remains equal to the inlet pressure. The valve seat bore 230 has an inner diameter _D1 . Diameter _D1 , as shown in Figures 4A and 4B , represents the diameter of a corresponding circular area _A1 above the plug 300. Because the pressure acting on the equal areas _A1 above and below the plug 300 is equal, the forces generated by the pressure in these areas cancel each other out.

These figures also show a diameter _D2 corresponding to the maximum expansion of the first annular seal ring 310, and a diameter _D3 corresponding to the maximum expansion of the plug body 300. The annular area A2 is defined by the circle with diameters _D1 and _D2 , and the annular area _A3 is defined by the circle with diameters _D2 and _D3 . The hydraulic pressure within the control chamber 250 acting on annular area _A2 acts to generate a net closing force on the plug ₃₀₀ , forcing the first annular seal ring 310 against the corresponding first annular sealing area 110, thereby maintaining the valve closed and sealed. The hydraulic pressure within the control chamber 250 acting on annular area _A3 acts on the outer portion 302 of the plug 300, opposing only the atmospheric pressure within the drainage passage. This tends to induce shear deformation within the outer portion 302, forcing the second annular seal ring 350 to seal tightly against the second annular sealing area 120. The breakdown of the force generated by the pressure acting on the area _A3 between the plug body and the peripheral portion where shear is applied depends on the elastic properties of the elastomer and the configuration of the plug (such as the depth of the annular grooves 330 and 306), as known to those skilled in the art, and can be adjusted according to the desired performance. However, a particularly preferred feature of certain embodiments of the present invention is that the second annular seal 350 is somewhat "independent" from the first annular seal 310, such that the second annular seal 350 has sufficient mobility to allow the seal 350 to close before the seal 310 contacts its valve seat and to maintain its seal even if the seal 310 fails to engage or is slightly open. (To provide this mobility, any rigid inner core 308 of the plug 300 is preferably constrained within a diameter _D2 .) Typically, this mobility, combined with the independent function, allows a significant portion of the force generated by the pressure on the area _A3 to be used specifically to enhance the seal of the second annular seal 350.

FIG5A schematically illustrates, in a single figure, the series of positions and progressively deformed shapes of the plug 300 during the final stages of valve closure. The successive positions and shapes of three states, labeled "A," "B," and "C," are schematically shown in partial outline of the plug 300. State "A" occurs instantaneously at the point in time when the downwardly extending second annular seal 350 contacts the second valve seat area 120, prior to the first annular seal 310 contacting the first annular valve seat area 110. In this position, water flow to the outlet 220 is blocked. The pressure acting on the underside of the plug 300 is reduced to atmospheric pressure by the drainage of water through the opening 510, thereby ensuring a continuous net force closing the plug 300.

As the plug 300 continues to move, in state "B," the first annular sealing ring 310 contacts the first annular sealing area 110, sealing water flow from the inlet 210 to the drain opening 510. As a result, the pressure within the drain opening 510 and around the corresponding annular leakage collection channel below the groove 330 drops to atmospheric pressure, and the pressure differential acting downward on the peripheral portion 302 is increased. This causes the edge of the sealing ring 350 to be further flattened, pressing it more tightly against the valve seat 120, resulting in the state marked "C." The pressure of the compressed air present in the dry pipe connected to the downstream port 220 applies an additional sealing force, further strengthening the seal.

In the preferred embodiment described thus far, it is advantageous to implement first annular valve seat region 110 and second annular valve seat region 120 as planar, coplanar surfaces, which may be distinct regions of a single, continuous, flat valve seat interrupted by drain opening 510. In this case, sealing ring 350 can be closed before sealing ring 310 by extending sealing ring 350 downward from the level of the remainder of plug 300. It should be noted that regardless of the variation in valve seat geometry, a similar effect can be achieved when sealing ring 350 is at the same level as sealing ring 310, or even higher than sealing ring 310. As a non-limiting example, FIG. 5B shows a view similar to FIG. 5A , in which second annular valve seat region 120 is raised due to a step between regions 110 and 120. In this case, the desired sequence of contact of the sealing ring 350 prior to contact of the sealing ring 310 can be achieved by using an edge of the sealing ring 350 that is at the same level as the sealing ring 310 but that contacts the corresponding raised seat contact surface 120 at position "A" prior to contact of the first annular sealing ring 310. The remaining structure and function of the valve remain unchanged.

Turning now to FIG. 6 , preferably, in the closed state of the valve, a continuous annular channel exists between the first annular seal ring 310 and the second annular seal ring 350. This channel extends around the entire periphery of the valve seat, allowing water that reaches the atmospheric pressure region between the seal rings to drain toward the drain opening 510. In some cases, the channel may be provided solely by an annular groove 330 of the plug 300, abutting a continuous, flat valve seat surface. Alternatively, as shown in FIG. 6 and FIG. 7A , the channel may be provided by a slot 124 cut into the valve seat surface, subdividing the regions 110 and 120. Alternatively, when the slot 124 is provided, the plug 300 may be implemented without the annular groove 330. Typically, the drain opening 510 extends through the valve body 100 from the bottom of the slot 124 to the drain conduit 500.

Now turning to Figure 7B, although several separate drainage openings 510 are described above as a series, it should be noted that the drainage channel can also be implemented in other forms, such as a long groove 512. Typically, the long groove 512 is arc-shaped to conform to the spatial contour between the first sealing area 110 and the second sealing area 120. The long groove 512 passes through the main body 100 to form a fluid connection with the drainage conduit 500.

As described above, in certain particularly preferred embodiments, the pressure differential between the control chamber 250 and the drain conduit 500 directly contributes to the formation of the contact pressure of the second sealing ring 350 on the second valve seat 120, particularly through compression or shear deformation transmitted via the peripheral portion 302 of the plug 300. However, it should be noted that this feature is not required. As an example, FIG8 illustrates a modified embodiment in which the second sealing ring 350 and the root of the diaphragm 400 are respectively connected to the body of the plug 300, without an intervening elastic bridge to transmit compression or shear deformation from the control chamber 250 to the second sealing ring 350. In this embodiment, the sealing of the second sealing ring 350 is achieved by the pre-formed elastic bias of the sealing ring, such that the second sealing ring 350 contacts the valve seat 120 before the first sealing ring 310 contacts the valve seat 110. The pressure of the compressed air within the pipe connected to the outlet 220 further compresses the edge with a force corresponding to the pressure differential between the compressed air pressure within the outlet pipe and the atmospheric pressure within the drain conduit 500.

It will be understood that the above descriptions are examples only and that many other embodiments are possible within the scope of the invention as defined by the appended claims.

Claims (5)

1. A valve for sealing and selectively opening a flow path from a water inlet to a dry outlet, said valve comprising: (a) A valve body having a valve opening and a second annular valve seat region, the valve opening being surrounded by a first annular valve seat region, the second annular valve seat region surrounding the first annular valve seat region; the valve body including at least one drain channel fluidly connected to a space between the first annular valve seat region and the second annular valve seat region, the drain channel providing a fluid drainage path to the outside of the valve body; (b) A plug, the plug being movable between an open state and a closed state for closing the valve opening, the plug having a first annular sealing ring and a second annular sealing ring, the first annular sealing ring being configured to seal a first annular valve seat region, the second annular sealing ring being configured to seal a second annular valve seat region, the plug being integrated with a diaphragm; and, (c) A cover that mates with the diaphragm to define a control cavity between the diaphragm and the cover; The plug has an outer periphery of elastic material to form a bridge between an upper outer periphery of the plug and the second annular sealing ring. This allows the outer periphery to undergo shear deformation based on a pressure difference between the control chamber and the drainage channel, thereby altering the closing force of the second annular sealing ring on the second annular valve seat region. The second annular sealing ring and the outer periphery of the plug are configured such that, during the movement of the plug from the open state to the closed state, before the first annular sealing ring contacts the first annular valve seat region, the second annular sealing ring first comes into contact with the second annular valve seat region; when the plug reaches the closed state, the second annular sealing ring elastically deforms to be pressed into contact with the second annular valve seat. 2. The valve of claim 1, wherein the second annular sealing ring has an expanding edge, and the expanding edge is configured such that the pressure difference between an outlet pressure at the outlet and a drain pressure in the drain channel enhances the sealing effect of the second annular sealing ring on the second annular valve seat region. 3. The valve as claimed in claim 1, wherein the plug, the diaphragm, the valve body, and the cover are configured such that when the pressure in the control chamber is equal to the pressure at the inlet, a net closing force serves to bring the first annular sealing ring tightly against the first annular valve seat region. 4. The valve of claim 1, wherein an annular groove formed on the upper surface of the plug defines a portion of the periphery of the resilient material of the plug. 5. The valve of claim 1, wherein the plug further comprises a rigid inner core to impart rigidity to a portion of the plug extending inward from the periphery of the elastic material.