Classifications

• • E—FIXED CONSTRUCTIONS
  • E03—WATER SUPPLY; SEWERAGE
  • E03B—INSTALLATIONS OR METHODS FOR OBTAINING, COLLECTING, OR DISTRIBUTING WATER
  • E03B9/00—Methods or installations for drawing-off water
  • E03B9/02—Hydrants; Arrangements of valves therein; Keys for hydrants
  • E03B9/025—Taps specially designed for outdoor use, e.g. wall hydrants, sill cocks
• • E—FIXED CONSTRUCTIONS
  • E03—WATER SUPPLY; SEWERAGE
  • E03B—INSTALLATIONS OR METHODS FOR OBTAINING, COLLECTING, OR DISTRIBUTING WATER
  • E03B9/00—Methods or installations for drawing-off water
  • E03B9/02—Hydrants; Arrangements of valves therein; Keys for hydrants
  • E03B9/08—Underground hydrants
• • E—FIXED CONSTRUCTIONS
  • E03—WATER SUPPLY; SEWERAGE
  • E03B—INSTALLATIONS OR METHODS FOR OBTAINING, COLLECTING, OR DISTRIBUTING WATER
  • E03B9/00—Methods or installations for drawing-off water
  • E03B9/02—Hydrants; Arrangements of valves therein; Keys for hydrants
  • E03B9/14—Draining devices for hydrants
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
  • F16K1/00—Lift valves or globe valves, i.e. cut-off apparatus with closure members having at least a component of their opening and closing motion perpendicular to the closing faces
  • F16K1/32—Details
  • F16K1/34—Cutting-off parts, e.g. valve members, seats
  • F16K1/46—Attachment of sealing rings

Definitions

• This invention generally relates to fluid valves and, more particularly, to frost-resistant water supply hydrants.
• a frost-resistant sill cock or hydrant typically includes an elongated tubular body with a valve mechanism at a first end and with a spout and a valve operator at a second, opposing end.
• the elongated body allows the valve mechanism to be positioned in an environment where frost or freezing is not likely to occur, such as inside a building or underground, while the spout and valve operator are positioned in a frost- or freezing-prone environment, commonly outside a building or otherwise out-of-doors.
• the operator is a handle, and an elongated actuator rod or stem extends within the tubular body between the handle and the valve, whereby manipulation of the handle moves the valve between open and closed positions.
• a predominant valve mechanism is what may be termed a "plunger valve,” wherein a valve plunger or stopper is screw-actuated into and out of sealing engagement with a valve seat. While the plunger valve provides a simple means for controlling flow from a water supply, it does not provide a truly positive control and is prone to damage during closing by over-tightening. That is, rather than screwing the valve plunger into a position of sealing engagement with the valve seat, a user will commonly forcibly close the valve, beyond the point of sealing, mashing and damaging valve seat and plunger sealing surfaces. Further, plunger valves do not readily lend themselves to adaptation for accommodating contemporary health concerns, specifically back- flow prevention, sometimes known as anti-siphoning.
• Back-flow preventers or anti-siphon devices are desirable to prevent contamination of the water supply caused by siphoning a contaminant back through the hydrant and into the water supply.
• Plunger-type valves which inco ⁇ orate an anti-siphon or back-flow prevention feature are commonly complicated with attendant reduced durability and added expense which often accompany complicated mechanisms.
• the durability of back-flow prevention and anti-siphon mechanisms may also be compromised by users who over-tighten valves upon closing.
• the vacuum breaker will break the "vacuum" in a hydrant which enables siphoning fluid back through the hydrant to the water supply, thereby offering additional anti-siphon protection.
• the vacuum breaker also offers structural protection to the hydrant in the case of a careless user who leaves a hose connected to the spout or spigot so that the hydrant does not properly drain, but may freeze and rupture. In this instance, the vacuum breaker releases the "vacuum” which holds water in the hydrant in some circumstances, allowing such residual water to drain from the hydrant.
• the plunger valve does not readily lend itself to the vacuum breaker function which is commonly accomplished with a separate mechanism.
• U.S. Patent No. 5,392,805 to Chrysler has attempted to overcome the above-noted problems by the provision of a frost-resistant hydrant having effective frost- resistance, back-flow prevention or anti-siphon protection, and integrated vacuum breaker protection without the use of conventional plunger valves.
• the hydrant has a conduit for connection with a fluid source, a valve cartridge positioned in the conduit, and a seal between the valve cartridge and the conduit to block- fluid from flowing between the valve cartridge and the conduit, directing the fluid through the valve cartridge.
• the valve cartridge has a cartridge body and a valve mounted in the cartridge body. The valve has an open position allowing fluid flow and a closed position blocking fluid flow.
• the valve cartridge further has an actuator stem extending from the valve for manipulating the valve between the open and closed positions.
• the stem extends away from the cartridge body.
• a fluid passage is defmed through the cartridge body, the valve, and the stem.
• the cartridge body includes a check valve having a seal disk, a first disk seat, and a second seat.
• the seal disk includes a plunger adapted to abut the second seat in sealing engagement.
• the seal disk further includes a seal seat adapted to abut the first disk seat in sealing engagement.
• the seal disk is normally biased by a spring against the first disk seat when the valve is closed.
• the plunger and disk arrangement is designed to relieve any negative pressure above a certain predefined amount to prevent back-flow from a hose when the valve is open and the water supply turned off.
• the movement of the plunger to relieve the negative pressure is directly dependent on the movement of the seal disk , which in turn is directly dependent on the force of the spring.
• the spring used to bias the seal disk against the seat requires a very tight tolerance, to provide the proper disk seal against fluid back-flowing into the water supply, and at the same time to permit the disk to unseat when a certain positive pressure is present.
• Another problem associated with the prior art may occur when the plunger overtravels and becomes lodged in the second seal seat. Even against the spring pressure, the plunger may not unseat to relieve the negative back pressure, and therefore fail to perform in a satisfactory manner.
• valve cartridge having a check valve, an anti- siphon seal disk and a vacuum breaker plunger.
• the seal disk is adapted to close a back-flow port
• the plunger is adapted to close a vacuum breaker port.
• the plunger includes at one end thereof a seal that slidably and sealingly reciprocates in a coaxial bore extending through the seal disk.
• a second seal is disposed at another end of the plunger for seating against the vacuum breaker port.
• a plunger head is located opposite to the plunger one end and is sized to be slidably received within a reduced diameter bore of the vacuum breaker port.
• An annular stop flange on the plunger head has a diameter greater than the bore to stop plunger movement once the second seal is seated in the vacuum breaker valve seat.
• the seal disk is biased toward sealing engagement with the back-flow port by a spring.
• the plunger is axially dimensioned so that when the seal disk is in sealing engagement with the back-flow port, the second plunger seal can be simultaneously seated in the vacuum breaker valve seat.
• a pair of axially extending slots are located in the seal disk to permit water pressure from any back-flow to act against the plunger thereby unseating the plunger from the vacuum breaker port.
• unseating of the plunger no longer depends on the spring.
• greater tolerance in spring requirements is possible, while significantly improving the vacuum breaker and back-flow operation.
• FIG. 1 is a fragmentary longitudinal section view of a prior art frost-resistant hydrant.
• FIG. 2 is a fragmentary longitudinal section view of a valve cartridge according to the present invention.
• FIG. 3 is a longitudinal section view similar to FIG. 2 with the ceramic valve and stem extension removed, showing the valve cartridge in normal operation when the valve is closed.
• FIG. 4 is a longitudinal section view similar to FIG. 3 showing the valve cartridge in normal operation when the valve is open.
• FIG. 5 is a longitudinal section view similar to FIG. 3 showing the valve cartridge in abnormal operation when the valve is open and the inlet is at zero or negative pressure.
• a prior art hydrant 10 having a conduit or body tube 12, a seat adapter 14 connected at a first end 16 of body tube 12 for connection with a fluid supply (not shown), such as a water supply pipe, for example, and includes a spout 18 connected at a second end 20 of body tube 12, opposite the first end 16.
• a valve cartridge 22 is slip-fit into position within body tube 12 and is located near the first end 16.
• Hydrant 10 also includes a handwheel or operator 24 connected with valve cartridge 22 through the stem extension 47 and actuator stem 40.
• seat adapter 14 is provided with a cylindrical exterior surface 26 which may be sized for press-fit engagement into conduit end 16, or may be sized for slip-fit engagement and soldering connection with body tube 12.
• a cylindrical exterior surface 26 which may be sized for press-fit engagement into conduit end 16, or may be sized for slip-fit engagement and soldering connection with body tube 12.
• external pipe threads 28 and an internal cylindrical bore 30 are provided for either screw or solder connection with the fluid supply.
• Spout 18 has a cylindrical bore 32 adapted to receive conduit end 20 for press-fit or solder connection.
• Spout 18 is provided with a hose nipple 34 (shown partially broken away), and internal threads 36 at an end of spout 18 opposite the connection of spout 18 with body tube 12.
• Valve cartridge 22 includes a cartridge body 38, an actuator stem 40, a valve 42 having a rotating disk 41 and a stationary disk 43, a retainer 44, a cartridge seal 46, and a stem extension 47.
• the actuator stem 40 operatively connects to the rotating disk 41 of the valve 42 to open and close the valve within a 90-degree rotation.
• a transverse opening 48 in the actuator stem 40 establishes communication between an interior chamber 50 and a waterway 52 within the body tube 12.
• the interior chamber 50 includes a back-flow port 54 defined by an annular groove 56 on the interior surface of the actuator stem 40 between the transverse opening 48 and the valve 42 and an O-ring 58 received therein.
• a sleeve 60 extends between the O-ring 58 and the end of the actuator stem 40 adjacent to the valve 42.
• An annular stop 62 is disposed in the actuator stem 40 at one end of interior chamber 50 away from the cartridge body 38 and defines a vacuum breaker valve seat 64 at a vacuum breaker port 66.
• the vacuum breaker port 66 permits communication between the interior chamber 50 and the stem coaxial bore 68.
• a check valve 70 disposed within the chamber 50 between the O- ring 58 and the vacuum breaker valve seat 64 comprises an anti-siphon seal disk 72 and a plunger 74.
• the seal disk 72 is adapted to close the back-flow port 54, and the plunger 74 is adapted to close the vacuum breaker port 66.
• the plunger 74 slidably reciprocates in a coaxial bore extending through the seal disk 72, and has an O-ring 76 disposed in an annular groove at the end thereof extending toward the vacuum breaker valve seat 64.
• the seal disk 72 is biased toward sealing engagement with the O-ring 58 by a spring 78 extending between the seal disk and the annular stop 62.
• the O-ring 76 on the end of plunger 72 is adapted to be in sealing engagement with the vacuum breaker valve seat 64.
• a head 80 on the plunger is spaced away from the O-ring 76 and is received in a recessed seat 82 in the seal disk 72.
• the head 80 includes an O-ring 84 in sealing engagement with the recessed seat 82.
• the O-ring 84 is adapted to contact a seal disk flange 86 when the plunger is in its fully extended position.
• the plunger is axially dimensioned so that when the seal disk is in sealing engagement with the O-ring 58, the O-ring 76 on the end of the plunger will be drawn away from the vacuum breaker valve seat 64 by the interengagement of the head 80 with the seal disk flange 86 through O-ring 84.
• the valve 42 is closed, and the waterway 52 is in communication with the stem coaxial bore 68 via the transverse opening 48 and the vacuum breaker port 66. In other words, vacuum in the hydrant is broken, and any residual water in the hydrant can exit through the spout 18.
• the material used for the 0-rings 58, 76, and 82 must be very soft to seal the vacuum breaker port during positive water flow at a pressure of less than three psi and before the seal disk 72 leaves the seat at O-ring 58, as required by ASSE 1019 SEC. 3.4.
• the plunger 74 can sometimes become lodged in the vacuum breaker valve seat when subjected to the upper pressure limits as required by ASSE 1019 SEC. 3.10 due at least in part to the softness of the O-ring 76.
• the plunger depends entirely on the interengagement of the head 80 with the seal disk flange 86 through O-ring 84 to break the vacuum seal.
• the seal disk in turn depends entirely on the spring 78 to return the seal disk into sealing engagement with the O-ring 58.
• the spring sometimes does not have enough force to dislodge the plunger for relieving back pressure from any water in the hose.
• the plunger refuses to dislodge from the vacuum breaker valve seat, water is free to back-flow from the hose and waterway into the valve cartridge. In this condition, the water cannot drain from the hydrant and may cause internal damage when subject to freezing conditions.
• the plunger refuses to dislodge in a negative pressure condition, water is free to back-flow from the hose and waterway, through the open valve, and into the supply line, thereby contaminating the line.
• the above-described arrangement also requires a tight manufacturing tolerance on the spring 78 in order to permit the plunger to be seated on the vacuum breaker valve seat 64 at the required pressure of three psi, while urging the seal disk against the O-ring 58 when the pressure is relieved.
• the small space reserved for the spring adds additional limitations to its tolerance. As a consequence, many of the springs being manufactured did not meet the strict tolerance requirements.
• FIG. 2 a fragmentary longitudinal section view of a valve cartridge 100 according to the present invention is shown, wherein like parts in FIG. 1 are represented by like numerals.
• the valve cartridge 100 includes an actuator stem 102, a valve 42, a retainer 104, and a cartridge seal and cartridge body (not shown) similar to the cartridge seal 46 and cartridge body 38 of FIG. 1.
• the actuator stem 102 operatively connects to the rotating disk 41 of the valve 42 to open and close the valve within a 90-degree rotation.
• a transverse opening 48 in the actuator stem 102 establishes communication between an interior chamber 106 and a waterway within the body tube (not shown).
• the interior chamber 106 includes a back-flow port 108 defined by an annular groove 110 on the interior surface of the actuator stem 102 between the transverse opening 48 and the valve 42.
• An O-ring 112 is received in annular groove 110.
• a sleeve 114 extends between the O-ring 112 and the end of the actuator stem 102 adjacent to the valve 42.
• An annular stop 116 is formed in actuator stem 102 and is defined by a reduced diameter portion 118 at one end of interior chamber 106.
• a frusto- conical section 120 adjacent to the annular stop 116 defines a vacuum breaker valve seat at a vacuum breaker port 122.
• the vacuum breaker port 122 permits communication between the waterway (not shown) and the stem coaxial bore 68.
• a check valve 124 disposed within the chamber 106 between the O-ring 112 and the vacuum breaker valve seat 120 comprises an anti-siphon seal disk 126 and a plunger 128.
• the seal disk 126 is adapted to close the back-flow port 108
• the plunger 128 is adapted to close the vacuum breaker port 122.
• the plunger 128 slidably reciprocates in a coaxial bore extending through the seal disk 126, and has an O-ring 130 disposed in an annular groove 132 of a flange section 134.
• the O-ring 130 is adapted to contact the inner bore surface of seal disk 128 when the plunger reciprocates therein.
• the plunger flange section 134 engages with an inwardly extending flange 135 of seal disk 126 to prevent separation of the plunger and seal disk.
• a second O-ring 136 is disposed in an annular groove 138 at a forward section of the plunger.
• a plunger head 140 located opposite to the flange section 134 is sized to be slidably received within the reduced diameter bore 118.
• An annular flange 142 on plunger head 140 has a diameter greater than the bore 118 to stop plunger movement once the O-ring 136 is seated in vacuum breaker valve seat 120.
• the annular flange 142 includes a frustro-conical surface 143 adapted to abut against the frustro-conical surface of vacuum breaker valve seat 120.
• the provision of cooperating structure for stopping the plunger is a significant improvement over the prior art since the plunger can no longer overtravel, and the O-ring is no longer subject to sticking.
• the seal disk 126 is biased toward sealing engagement with the O-ring 112 by a spring 144 extending between the seal disk and a spring seat 145 of the actuator stem 102.
• the plunger is axially dimensioned so that when the seal disk is in sealing engagement with the O-ring 112, the O-ring 136 adjacent to flange 142 can seat in the vacuum breaker valve seat 120.
• a pair of axially extending slots 146 (only one shown) disposed in opposite sides of seal disk 126 permits water pressure from any back-flow to act against flange section 134 and O-ring 130 to unseat the plunger from breaker valve seat 120. This is a significant improvement over the prior art since unseating of the plunger no longer depends on the spring. Thus, greater tolerance in spring requirements is possible, while significantly improving the vacuum breaker and back-flow operation.
• two slots are described in relation to the seal disk, only a single slot or greater than two slots can be provided.
• the slots may alternatively be located in the plunger and may take any shape desired, as long as the back-pressure unseats the plunger from the vacuum breaker seat.
• valve 42 In the state of normal operation, as shown in FIG. 3, valve 42 is closed, seal disk 126 is seated against O-ring 112, and O-ring 136 is seated against vacuum breaker valve seat 120. There is no communication between the waterway and the stem coaxial bore 68 as in the prior art.

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• Engineering & Computer Science (AREA)
• Health & Medical Sciences (AREA)
• Life Sciences & Earth Sciences (AREA)
• Hydrology & Water Resources (AREA)
• Public Health (AREA)
• Water Supply & Treatment (AREA)
• General Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Details Of Valves (AREA)

Applications Claiming Priority (3)

Publications (1)

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ID=21749442

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Country Status (4)

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• 1997
  • 1997-02-06 WO PCT/US1997/001961 patent/WO1997029248A1/en not_active Application Discontinuation
  • 1997-02-06 EP EP97905829A patent/EP0819199A1/de not_active Withdrawn
  • 1997-02-06 AU AU22628/97A patent/AU2262897A/en not_active Abandoned
  • 1997-02-06 CA CA 2215994 patent/CA2215994A1/en not_active Abandoned

Non-Patent Citations (1)

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