Check valve and shut-off reset device for liquid delivery systems

A check valve assembly which in an open position allows liquid to flow in one direction through the assembly including a moving sealing member which engages a seal to prevent liquid flow in a second opposite direction. The sealing member may be moved into engagement with the seal by rotation of a stem with an eccentric to block flow in both directions. A check valve and shut-off device assembly which in an open position allows liquid to flow in one direction through the assembly until gas or foam is mixed with the liquid. The shut-off device includes a sealing member which engages a seal to block flow through the assembly when foam or gas is present in the liquid. The check valve includes a sealing member which can reset the shut-off device. The check valve sealing member also engages the same sealing member to prevent any flow through the assembly in a closed position. In an open position, the check valve sealing member may engage the seal to prevent reverse flow of liquid through the assembly.

TECHNICAL FIELD

The present disclosure relates generally to check valves for use with liquid delivery systems.

BACKGROUND

Conventional ball valves may include a spherical or semispherical shaped sealing member within a liquid flow passage. The sealing member may include a central opening through which liquid may flow depending on the orientation of the sealing member within the flow passage. To prevent liquid flow about the sealing member, seals may be providing along inner walls of the flow passage which engage an outer portion of the sealing member. Typically, a seal is provided on each of the upstream and downstream sides of the valve and the seals are spaced apart wider than the width of the central opening through the sealing member.

When open, the central passage of the sealing member of a conventional ball valve is generally oriented parallel to an axis of flow through the flow passage. As a conventional ball valve is closed, the central opening of the sealing member is rotated away from alignment with the axis of the flow passage. When fully closed, the central opening of the sealing member will typically still contain a certain amount of the liquid. This liquid is held within the central opening by the same seals that prevent flow of liquid about the sealing member.

The fluid held within the central passage of a closed ball valve may be begin to deteriorate or to stagnate. When the valve is reopened, the degraded fluid with the central passage may enter the fluid delivery system downstream of the valve and may contaminate the liquid being delivered.

Other conventional valve types may also include pockets or recesses where liquid being transported through the valve may become trapped.

It is desirable to improve on valves used in liquid delivery systems.

In stadiums and other large facilities that may have a number of concession stands spread out over a large area, it is common to centralize the liquid supply for beer, soda and other drinks that may be dispensed at the concession stands or other points of purchase. Liquid delivery networks are provided to transport liquid from the central supplies to each concession stand. It is not uncommon for delivery lines to extend for four hundred to eight hundred or more feet. In such installations, it is desirable to have a sensor at the supply end of the line to shut off flow into the line when a soda container or beer keg has been depleted and gas starts to enter the line. If the gas is permitted to run the length of the supply line to the tap, it can take an undesirable amount of time to refill the lines after the soda or beer has been replaced.

Self-closing control valves for use with such installations are known. An example of such a liquid/gas shut-off valve is described in U.S. Pat. No. 5,630,441, the disclosure of which is incorporated herein by reference. However, these self-closing valves require a reset mechanism once the source of beer or soda has been replaced. Different versions of resets have been developed but none is completely satisfactory.

Problems with conventional approaches to resetting these self-closing valves include a lack of robustness and requiring a high degree of precision or care in operation.

Another issue with conventional self-closing valves and reset options is that often these valves and resets also act as check valves. When it is necessary to clean the delivery lines between the source and the tap, bi-directional flow of cleaning solution through the lines may be desired. The check valves used in the self-closing valves and the valve resets may either prevent or hinder the flow of cleaning solution through the delivery lines.

Improvements to resets for self-closing valves and for check valves used in liquid delivery systems are desirable.

DETAILED DESCRIPTION

Reference will now be made in detail to exemplary aspects of the present invention which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.

Referring now toFIG. 1, a check valve and valve reset assembly100may include a shut-off valve assembly102and an antiback-flow/valve reset assembly104. Assembly100is configured to allow a flow of liquid as part of a liquid distribution system. Under normal operating conditions, liquid flow through assembly100is into a first end106of valve assembly102and out of a second end108of reset assembly104. Reset assembly104includes a handle110that may be used to configure reset assembly104for normal uni-directional liquid flow, resetting valve assembly102(as will be described below), or permitting bi-directional liquid flow. Note that handle110may include indicia such as an arrow or other marking which cooperates with markings on a valve reset body to indicate whether the condition or positions of internal components within assembly100, as will be discussed further below. A thumbscrew or similar lock-out device112may be included to aid in the configuration of reset assembly104for bi-directional flow, such as might be used for flushing or cleaning a liquid delivery system to which assembly100may be connected. Thumbscrew112may also include indicia cooperating with markings on an exterior of the reset valve body to indicate the condition or positions of internal components, as will be discussed further below.

As shown inFIGS. 2 and 3, valve assembly102includes a second end114which mates with a first end116of reset assembly104, providing a sealed connection between a central axial passage118of valve assembly102and a central axial chamber120of reset assembly104. Liquid is permitted to flow through assembly100from first end106to second end108through the axial chambers118and120. In some installations, such as systems for delivering or distributing carbonated beverages, it may be desirable to ensure that only liquid is allowed to pass through assembly. Shut-off valve assembly102is configured similar to the devices disclosed in U.S. Pat. No. 5,630,441, the disclosure of which is incorporated herein by reference, and may operate to shut a fluid connection between axial chamber118and120if gas enters valve assembly102through first end106. A sealing member, such as a ball122is provided within valve assembly102, is urged against a sealing member, such as O-ring124, when gas enters axial chamber118, and prevents the flow of gas and liquid through second end114of valve assembly102. This sealed or shut-off position is shown inFIG. 3.

Reset assembly104includes a rotating stem128to which may be mounted handle110. A reset member126is positioned within chamber120between stem128and seal124. Thumbscrew112includes a stem133which extends to, and selectively engages reset member126. As shown in an open flow position inFIG. 2, liquid is permitted to flow through first end106into axial chamber118past ball122, through second end114and past reset member126to second end108. InFIG. 3, ball122has moved to engage seal124and prevent flow between assemblies102and104, due to gas within the liquid entering through first end106. When a proper liquid flow has been restored through first end106, a manner of moving ball122from seal124is required to reestablish liquid flow through assembly100.

Referring now toFIGS. 4 to 6, handle110and connected stem128have been rotated approximately ninety degrees to place reset assembly104into a closed/reset position. As shown inFIGS. 5 and 6, stem128includes a portion130which engages reset member126and urges the member into engagement with seal124. In engaging seal124, reset member126also engages ball122and displaces ball122from engagement with seal124. Note that flow is still blocked between chamber118and120but that liquid within chamber118is now permitted past ball122and seal124. Reset member126now cooperates with seal124to prevent movement of liquid into chamber120. If desired, first end106of assembly102may be connected to a new source of liquid, such as a fresh keg of beer or another new source of carbonated liquid. As shown, sealing member126is generally sized similarly to ball122so that the same seal124can engage both and form an acceptable seal to prevent unwanted movement between chambers118and120. It is desirable that member126as it engages ball122define a semi-spherical shape to engage seal124and that this shape be of a similar radius to ball122. The remainder of member126as it engages stem133and is engaged by portion130of stem128, may be sized and shaped as desired for manufacturing or assembly efficiency, maximum flow, or even aesthetic desires.

Once a proper liquid flow has been established to valve assembly102, handle110and stem128may be returned to the open position shown inFIG. 2. This permits reset member126to move away from seal124due to pressure from the liquid within chamber118. Assuming that liquid pressure within chamber118is higher than liquid pressure within chamber120, reset member126is displaced from seal124and flow between first end106and second end108is reestablished. Note that with stem128in the open position, reset member126is free to move between seal124and stem128. However, if liquid flow begins to reverse, meaning that liquid begins to flow through second end108toward first end106, this liquid flow would urge reset member126into engagement with seal124and prevent backflow into chamber118. Thus, assembly104may operate as both a valve reset device and a backflow prevention device.

Note that inFIG. 6, stem133of thumbscrew112is retracted away from reset member126as much as possible (complete removal of stem133and thumbscrew112is prevented by retainer132). In this position, stem133may extend into a cavity134in reset member126to prevent rotation about a longitudinal axis of chamber120of reset member126, while still permitting reset member126to move freely between stem128and seal124. In this position, stem133does not impede the anti-backflow operation of member126within chamber120.

Referring now toFIGS. 7 and 8, thumbscrew112is shown in a lowered or cleaning position. Stem133is engaged by recess134of member126and prevents longitudinal movement of reset member126between stem128and seal124. A passage136is formed between reset member126and seal124and movement of reset member126to operate as an anti-backflow device is prevented. In this position, reset member126also prevents ball122from engaging seal124and blocking flow going from first end106to second end108. While ball122may move further away from seal124, the position of reset member126ensures that at least a passage138is defined between ball122and seal124. These two passages ensure that a cleaning solution may be flushed through assembly100in both directions.

As shown inFIG. 23, a prior art valve500such as might have been used to engage ball122and move the ball out of engagement with seal124. Such a valve500would provide a shut-off reset function but in a bi-directional flow position, such as shown inFIG. 23, the passages502between ball122and seal124are quite small and may undesirably impede flow of cleaning solution around ball122. If there are extensive lines that need to be cleaned or flushed during such an operation, an desirable amount of time or pressure may be required to complete the cleaning or flushing. Also note that valve500requires a separate seal504and cannot make use of seal124to halt flow when valve500is placed in a closed position.

Referring now toFIGS. 2 and 5, assembly100may include a drain140within which may be positioned a ball seal144urged into a sealed position by a spring142. In a sealed position (shown inFIG. 2), ball144is seated against and seals an opening146which is in fluid communication with an annular groove148about stem128. Annular groove148is in turn in fluid communication with a central axial opening150. In the sealed position, liquid, or a mixture of liquid and gas is not permitted to pass out of chamber118through drain140and exit from assembly100. In an open position (shown inFIG. 5), a portion of stem128displaces ball seal144from opening146and permits liquid or a mixture of liquid and gas to flow from chamber118out of assembly100. Such a drain140may be useful to drain any liquid and gas combination within chamber118that may have caused ball122move forward and engage seal124within shut-off assembly102. If this undesired gas is not drained from within chamber118, then ball122will immediately move back against seal124even after ball122has been displaced from seal124and reset.

In use, drain140may be placed in the open position when handle110is moved to urge reset member126against seal124. For example, in a beer distribution arrangement, a beer keg with which assembly100is in connected to may have run empty and some beer foam may have entered chamber118. This beer foam will cause ball122to move toward and engage seal124, stopping flow of the foam into chamber120. Assembly100may then be disconnected from the empty beer keg and connected to a full keg. Any beer and beer foam mixture within chamber118needs to be vented so that shut-off assembly102will permit flow from chamber118. Any residual foam within chamber118will immediately cause ball122to engage seal124and prevent flow. Thus, as handle110is moved to a position to move reset member126into engagement with seal124and displace ball122from seal124, drain140may be opened to permit any foam within chamber118to escape. Observation of any liquid or liquid and gas (foam) flowing from opening150of stem128will indicate when the undesirable material has been cleared from chamber118. Once this is observed, handle110may be moved back to the open position and flow from first end106to second end108may be reestablished.

Note that when thumbscrew112of assembly100is in a cleaning position, handle110may remain in the open position. This permits flow of a cleaning liquid through assembly100without permitting such liquid to exit through drain140. If it is desired to flush drain140, handle110may then be moved so that a portion of stem128displaces ball144from opening146. Stem128may be configured so that the movement necessary to displace ball144may be accomplished with thumbscrew112in the cleaning position (i.e., so that stem128is not rotated enough to engage reset member126, which is held in position by stem133of thumbscrew112). Thus, at some intermediate position between open and closed for handle110, a drain position would be defined. Alternatively, stem128may be configured so that drain140is moved to the open position when handle110is in the closed position.

Referring now toFIGS. 9 to 11, an alternative embodiment anti-backflow/valve reset assembly200includes first end116, second end108and handle110. Handle110is mounted to a stem202which rotates within assembly200as handle110is moved between open and closed positions. Within an axial chamber204, a ball206is captive between stem202and seal124. A seal retaining insert208is positioned within assembly200to retain seal124within a groove210. A positioning ring212is positioned within chamber204and about ball206to ensure that ball206stays centrally located within chamber204while permitting liquid to flow from first end116to second end108. Note that assembly200does not include a drain and stem202does not include a drain actuating portion, as shown inFIGS. 1 to 8, above, and is not configured to hold ball206in a cleaning position. In this configuration, assembly200may be used either in concert with a shut-off valve assembly, as shown above, where it is not necessary to have bi-directional flow for cleaning or flushing. Alternatively, assembly200may be used where a check valve or anti-backflow device is required in a liquid delivery system.

FIGS. 9 and 10show assembly200with handle110is the open position, where ball206is free to move within positioning ring212between stem202and seal124. Liquid is permitted to flow through chamber204from first end116to second end108. Movement of liquid in an opposite direction will urge ball206away from stem202and into engagement with seal124, preventing backflow through assembly200.FIG. 11shows assembly200with handle110in a closed position, where a portion such as eccentric214of stem202is pressing ball206against seal124and preventing all liquid from flowing through chamber204.

The advantage of assembly200with regard to a more traditional rotating valve assembly500ofFIG. 23, is that a common seal124such as an O-ring provides a sealing surface against which ball or sealing member206is pressed to block flow. The member is generally stationary when engaging the seal. A rotary valve, such as assembly500requires a seal that is more complex in shape and against which the sealing member must rotate when the valve is moved between open, closed and intermediate positions. Maintenance of assembly200is also quire simple. A plate216defines an opening218through which a shank of stem202extends. Plate engages a shoulder224of stem202and holds the stem in position within assembly200. Plate216also defines a second opening220through which a removable fastener222, such as a screw, extends and engages a body226of assembly200.

Inspection or replacement of the internal parts within assembly200may be accomplished by removing insert208, allowing seal124to be removed, inspected and replaced, and by moving handle110from the open position to permit fastener222to be removed. Plate216is then free to be removed a stem receiving opening228of body226. One or more O-rings230may be positioned about stem202to prevent flow from within chamber204through stem opening228. These O-rings230may be inspected and replaced with stem202removed from body226. Which stem202removed, ball or sealing member206and positioning ring212can be removed, inspected and replaced. With insert208repositioned to hold in seal124, ball206and positioning ring212can be replaced within chamber204, stem202reinserted into opening228, capturing ball206between stem202and seal124. With the reinsertion of screw222through plate216, stem202is secured to body226and assembly200is ready for installation in a liquid delivery line.

Assembly104, above, is similarly configured to disassembly and maintenance. Stem128extends entirely through a body152within an opening154(seeFIG. 2). However, opening154and stem128are configured to permit removal of stem128by removing fastener222from plate216. With stem128removed, reset member126may be removed, inspected and replaced. With the removal of a seal retaining insert156, seal124can be removed, inspected and replaced.

Referring now toFIGS. 12 and 13, seal retaining insert156may include an annular groove160in a seal retaining face158. One or a plurality of channels162may be formed from an interior space164which is in fluid communication through an first end168with chamber118when installed within assembly100, as shown above. A second end166of insert156is positioned adjacent seal124and permits ball122to extend through and engage seal124when shut-off valve assembly102is actuated. Groove160is in fluid communication with drain140and permits liquid or liquid and gas to be vented or drained as needed before assembly100is returned to the open position. Insert156is sized and configured to fit within first end116of body152and then be held in place against seal124by second end114of valve assembly102. As shown above, valve assembly102is threadably received within reset assembly104but other releasably mounting arrangement are also contemplated within the scope of the present disclosure. Such arrangements might include but not be limited to quarter- or half-twist connections, rotating collar connections, and other releasable means of connecting the two assemblies in a liquid-tight fashion.

Referring now toFIGS. 14 to 16, stem128includes sealing member actuating portion130and a shank portion170which is configured to receive plate216. A pair of flats176may be formed in a handle receiving end178to engage handle110and permit rotation of stem128via handle110. An upper seal groove180is provided for a sealing member such as O-ring to seal against an interior wall of stem opening154. A pair of lower seal grooves are provided to receive sealing members such as O-rings both above and below annular groove148which provides fluid communication between drain140and central axial opening150via a channel182. Seals in grooves172keep liquid being drained from chamber118flowing through opening150and not about a lower portion of stem128. Within annular groove148are one or more drain valve actuation elements which are configured to selectively engage ball144when handle110and stem128are positioned to permit drainage from chamber118through drain140and out of opening150.

Central portion184of stem128is configured to be positioned within chamber120and permit flow of liquid from chamber118out second end108. A narrowed shaft portion186extends within central portion184and provides a mounting point for member actuating portion130. Preferably, central portion184is sized as needed to provide adequate strength for moving reset member126into engagement with seal124but is also kept as small as possible so as to minimize resistance to liquid flow through chamber120.

Referring now toFIGS. 17 to 20, reset member126includes a first generally spherical end188and an opposite end190. First end188is sized and shaped generally spherically (or semi-spherically) to engage and form a liquid-tight seal with seal124. Preferably, first end188is generally matched, size-wise, to the size of ball122to ensure that both will work effectively with seal124. Second end190is shaped and configured to be engaged by portion130of stem so that reset member126may be urged into engagement with seal124. While shown as generally semi-spherical in shape, it is not intended to limit the second end of reset member126to any particular shape, as long as that shape is compatible with the shape of portion130of stem128. Recess134is formed in a first radial extension192extending outward from a central body198of reset member126. Recess134includes at least one sloped inner wall196to aid in guiding stem133into recess134as thumbscrew112is advanced into body152. As stem133is advanced deeper into recess134, sloped wall196will help move reset member126into the desired position for cleaning or bi-directional flow through assembly100. While walls196are shown as defining a constant slope, other shapes or configurations are contemplated which would aid in the positioning of reset member126as stem133advances deeper into recess134.

At least a pair of solid radial extensions194may be provided about body198spaced apart from first extension192. These extensions cooperate to position reset member126centrally within chamber120and permit liquid flow about reset member126. While a total of three radial extensions are shown, this number is intended only as a minimum number and the total number of extensions may be higher. Also, recessed extension192and solid extensions194are shown, but reset member126may be configured with more recessed extensions and the more or fewer solid extensions within the scope of the present disclosure. A central opening199is shown at a bottom of recess134which may provide a stop to positively engage stem133and secure reset member126in the cleaning or bi-directional flow position. Opening199may or not extend laterally through reset member126as shown.

Referring now toFIGS. 21 and 22, positioning ring212includes an outer ring portion230and at least three sealing member positioning portions232extending inward from ring portion230. Positioning ring212serves to generally center ball206of assembly200within chamber204. Similar to the extensions of reset member126, described above, positioning ring212keeps ball206positioned to engage seal124when stem202is rotated to urge ball206to a closed position. Ball206is received within a central opening234and is permitting to move longitudinally between stem202and seal124when handle110is in the open position. Positioning portions232are preferably sized so that ball206is able to move freely within ring212while maintaining the ball generally centrally within chamber204. Ring portion230is preferably sized to fit closely to an interior wall of chamber204and to be configured a thin as possible to minimize any impedance to flow through assembly200.

Referring now toFIGS. 24 to 27, a further alternative assembly500includes a valve reset assembly104and a shut-off valve assembly502with a slide506within central axial passage118. Shut off valve assembly502is configured similarly to valve assembly102, with the exception of the arrangement of the slides within the respective assemblies. Referring now also toFIG. 3, valve assembly102includes a slide406positioned within a slide receiving area408of passage118defined by valve body103. Slide406is urged away from seal124and toward a shoulder414at an opposite end of area408by a spring410. A corresponding shoulder412of slide406engages shoulder414and provides a seal against fluid movement within passage118. When there is pressure sufficient exerted through end106into passage118by fluid trying to flow from end106to end108, the fluid will overcome spring410, displacing shoulder412from shoulder414and permit the fluid to flow toward end108.

As shown inFIG. 3, slide406is much smaller in diameter than area408and can move about side to side within the area. Further, spring410is required to push the entire slide to bring the shoulders into engagement and seal against fluid flow. If the slide is laterally displaced from the center of the area, the shoulders may not engage each other properly to seal against fluid flow.

FIGS. 24 to 27show an alternative slide506within area408. Slide508includes a fixed portion520and a movable portion522with a spring510positioned to press against fixed portion520and urge movable portion522toward shoulder414. Movable portion522includes a mating shoulder524which engages shoulder414and creates a seal within passage118when fluid pressure from end106fails to overcome spring510. Movable portion522is received within a central opening526of fixed portion520, and ball seal122is also received within central opening526. Preferably, movable portion is sized generally close to ball122and central opening526is sized to receive both to allow easy axial movement without excessive lateral movement.

Referring now toFIGS. 25 to 27, fixed portion520of slide506includes a plurality of radial extensions528on an outer surface530. Extensions528are sized to extend to and generally engage an inner surface of area408. Between this inner surface of area408and outer surface530of fixed portion520is an open area through which fluid may flow through passage118from end106toward end108. After passing over outer surface530, the fluid would pass over narrower portion538and pass through a plurality of openings532and over seal124into the downstream portions of assembly500.

Movable portion522also includes a inner passage536into which fluid may pass from passage118through an opening534. When the fluid in generally uniform, with no air or gas bubbles in the flow, and ball122is displaced from seal124, fluid may flow into inner passage536through opening524but not displace ball122toward seal124. However, once gas bubbles within the fluid flow reach opening534from end106, the gas enters inner passage536and acts upon ball122to force ball122against seal124and shut off flow. If the fluid source, such as a beer keg, attached to end106is removed or disconnected to be replaced with a fresh source, fluid pressure through end106drops below the force exerted by spring520and shoulder524of moveable portion522is brought into engagement with shoulder414. Shut-off valve502is then blocking flow in both directions through passage118.

As described above, when a fresh fluid source is reattached to end106, the fluid pressure may then overcome spring510and move shoulders414and524apart. Reset104may be actuated to push ball122from seal124and permit flow from end106to108to resume.

Referring now toFIG. 28, a further embodiment of a slide806for use with a check valve and valve reset assembly according to the present disclosure includes an upstream end808and is configured similar to slide406and slide506described above to receive ball122within end526. Slide806is further configured with an outer surface830with radial extensions528to maintain the slide's position within the check valve and maintain shoulders within the valve in alignment. A shoulder812for engaging shoulder414within opening408is provided with one or more flats850positioned about the shoulder. Flats850are positioned so as to not interfere with the engagement between shoulders812and414to prevent flow through the check valve. While flats850do not interfere with the seal to stop flow, they do provide a larger opening for fluid flow through the check valve when the shoulders are disengaged and the shoulders are separated to allow flow.

FIG. 29illustrates a check valve and valve reset assembly600according to the present disclosure. Assembly600includes an upstream end612into which fluid under pressure may flow and a downstream end610from which fluid under pressure may flow. Adjacent the upstream end is a check valve assembly604and adjacent the downstream end is a valve reset assembly602with an actuating handle614. As shown, handle614is rotatable between a normal operating position and a valve reset and cleaning position. To move between the two positions, handle614may be swung through approximately ninety degrees of rotation. It is not intended to limit the present disclosure to just including a valve reset assembly having two positions as it may be desired to include a third shut off position as described above.

Included in assembly600may be a vent arrangement permitting, gas, liquid, foam or a combination of gas, liquid or foam from within the assembly to removed to restore the flow of clear liquid through assembly600. The vent arrangement shown inFIG. 29may include a vent valve608and a vent line606.

Referring now also toFIGS. 30 and 31, vent valve608is in fluid communication with an interior616of assembly600and vent line606. Vent valve608is preferably a selectively activated valve that permits the venting of interior616only upon action by a user. As shown, vent valve608is a push-on type valve, meaning that a user would press an outer moveable portion618of valve608inward toward interior616which would permit liquid or gas within interior616to exit through valve608and into vent line606. Typically, such venting would be done when ball122is in the closed position so that the only path for liquid or gas within interior616or upstream of assembly600is through vent valve608. Vent line606may preferably be a clear or translucent line so that a user can see when clear liquid has begun to exit interior616through vent valve608, meaning that the liquid in the line is ready for dispensing. At this point, vent valve608may be closed and reset assembly602actuated to reestablish flow through assembly600through downstream end610.

As shown inFIGS. 29 to 31, vent valve608may be positioned as part of check valve assembly604. Referring now toFIG. 32, vent valve608may be positioned as part of a reset assembly702attached to a check valve assembly704as part of a check valve and valve reset assembly700according to the present disclosure.

Referring now toFIGS. 30 and 32, assembly600includes a rotating stem620connected to handle614and extending into interior616of reset assembly602of assembly600. Stem620is configured to engage and rotate with the movement of handle614. Within reset assembly602a reset member622is slidably received. Reset member622includes a recessed central portion that receives and engages an inner end of stem620. InFIG. 30, handle614is positioned in a normal operating position where reset member is able to move within interior616but limited in travel by the engagement of the inner end of stem620within the central recess of the reset member. Since pressurized liquid within interior616will preferably flow from upstream end612to downstream end610, the flow of the liquid will tend to keep reset member622from proximity of a seal621positioned between reset assembly602and check valve assembly604. Thus, reset member will not block the flow of liquid through the interior in this normal operating position.

Referring now toFIG. 31, handle614is shown in the reset and cleaning position, rotated approximately ninety degrees from the normal operating position shown inFIGS. 30 and 32. In this reset and cleaning position, stem620is also rotated to the same extent as handle614. The inner end of stem620now engages the central recess of reset member622and urges the member toward seal621. A first end634of reset member622now extends through seal621and may engage ball122to prevent the ball from engaging the seal and preventing flow through interior616. While end636extends through seal621, reset member622does not engage the seal, permitting flow through interior616past both reset member622and ball122.

If the check valve has been actuated, so that ball122is engaging seal621to prevent flow through interior616, the reset and cleaning position of handle614and reset member622removes ball122from engagement with seal621to reestablish flow through interior616. Once flow has reestablished, handle614may be returned to the normal operating position with check valve assembly604reset to again sense the presence of foam in the liquid stream and cut off flow when that occurs.

If cleaning and flushing of interior616is desired, handle614may be placed in the reset and cleaning position. In this position, flow of liquid through interior616in both directions may be accomplished without either the reset member and/or the ball engaging seal621. Once cleaning is complete, handle614may be returned to the normal operation position so that ball122and check valve assembly604may be reset to serve as a foam sensing check valve.

FIG. 33shows stem620with an outer end626to extend outside of reset assembly602and may include flats or other geometric surface628to assist in the engagement of and rotation with handle614. An inner end630is configured to extend within interior616and engage reset member622with an inner flange632. A central portion634may be configured to received a seal such as an o-ring to prevent liquid within interior616from leaking past stem620.

FIG. 34shows reset member622with first end634and a second opposite end636. A central recess638is formed between the ends for receiving and engaging inner end630and inner flange632of stem620. Recess638includes an open end640through which a narrower portion of inner end630may extend and a closed end642within which inner flange632may extend. An exterior surface644is smaller in size than the interior so that liquid can flow about the reset member the assembly. A plurality of raised ribs646on the outer surface position the reset member within the interior.

As shown inFIGS. 30 and 32, inner flange632is shaped as sort of a cam extending generally perpendicular to an axis of rotation of the stem, with the flange having a wider dimension and a narrower dimension oriented generally ninety degrees from each other. Inner end630and inner flange632engage recess638of reset member622. In the normal flow position, a wider dimension of inner flange632is oriented to allow reset member622to move away from seal621by the force of liquid flowing through interior616. This prevents reset member622from engaging seal621and also prevents reset member622from interfering with the operation of ball122of check valve assembly604.

As shown inFIG. 31, in the reset position, the wider dimension of inner flange632is oriented to now urge reset member622toward seal621so that first end634extends through and blocks ball122from engaging seal621.

Assembly600and Assembly700are similarly configured with rotating stem620and reset member622so that rotation of handle614places the assemblies into either normal operation position or reset and cleaning position, without the need to a separate screw engaging the reset member, as described in the earlier embodiments. Having stem620directly engage reset member622permits possibly greater efficiency is manufacturing and assembly due to a reduced part count and a simpler outer housing for reset assemblies604and704.

While the invention has been described with reference to preferred embodiments, it is to be understood that the invention is not intended to be limited to the specific embodiments set forth above. Thus, it is recognized that those skilled in the art will appreciate that certain substitutions, alterations, modifications, and omissions may be made without departing from the spirit or intent of the invention. Accordingly, the foregoing description is meant to be exemplary only, the invention is to be taken as including all reasonable equivalents to the subject matter of the invention, and should not limit the scope of the invention set forth in the following claims.