US3699944A

US3699944A - Anti-siphon and vent means for use with an open-to-atmosphere hot water supply tank

Info

Publication number: US3699944A
Application number: US114147A
Authority: US
Inventors: Harvey R Karlen
Original assignee: Cory Corp
Current assignee: Cory Corp
Priority date: 1971-02-10
Filing date: 1971-02-10
Publication date: 1972-10-24
Anticipated expiration: 1989-10-24
Also published as: NL7200681A; NO135110B; DE2163235A1; AU3648271A; AU463077B2; NO135110C; CH528054A; SE385403B; IT948087B; FR2126713A5; ES398513A1; BE776471A; CA954411A; GB1363898A

Abstract

An anti-siphon and vent means for use with an open-to-atmosphere hot water supply tank. The anti-siphon and vent means is mounted downstream of a shutoff valve for controlling flow conditions relative to the hot water heating tank. The anti-siphon and vent means is arranged to permit free flow of cold water to the tank when the shutoff valve is open and to vent the tank to atmosphere and prevent backflow of water from the tank to the shutoff valve in the event of a failure of pressure in the cold water supply through the valve.

Description

United States Patent Karlen 51 Oct. 24, 1972 [72] Inventor:

[54] ANTl-SIPHON AND VENT MEANS FOR USE WITH AN OPEN-TO- ATMOSPHERE HOT WATER SUPPLY TANK Harvey R. Karlen, Chicago, Ill.

[73] Assignee: Cory Corporation [22] Filed: Feb. 10, 1971 [21] Appl. No.: 114,147

[52] US. Cl. ..126/362 [5 l Int. Cl. ..A47g 23/04 I [58] Field of Search...l26/35O R, 362; 137/339, 340,

[56] References Cited UNITED STATES PATENTS 114,347 5/1971 Robb ..126/362 2,927,598

3/1960 Thompson ..l37/2l8 332,147 12/1885 Goering ..l26/362 3,424,188 l/l969 Whitaker et al. ..137/218 3,180,352 4/1965 Kersten et a1 ..l37/218 Primary Examiner-Frederick L. Matteson Assistant Examiner-W. C. Anderson Attorney l-lofgren, Wegner, Allen, Stellman & Mc- Cord [s7] ABSTRACT An anti-siphon and vent means for use with an opento-atmosphere hot water supply tank. The anti-siphon and vent means is mounted downstream of a shutoff valve for controlling flow conditions relative to the hot water heating tank. The anti-siphon and vent means is arranged to permit free How of cold water to the tank when the shutoff valve is open and to vent the tank to atmosphere and prevent backflow of water from the tank to the shutoff valve in the event of a failure of pressure in the cold water supply through the valve.

9 Claims, 2 Drawing Figures ANTI-SIPHON AND VENT MEANS FOR USE WITH AN OPEN-TO-ATMOSPHERE HOT WATER SUPPLY TANK BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to hot water supply systems and in particular to means for controlling the delivery of cold water to a hot water heating tank.

2. Description of the Prior Art In one form of hot water supply apparatus, cold water is delivered through an inlet to a lower portion of a hot water tank thereby displacing hot water outwardly through a discharge outlet communicating with an upper portion of the tank. The discharge outlet is maintained open to atmosphere at all times and the control of the water flow is effected by a shutoff valve in the cold water supply means.

It is desirable in such hot water supply systems to prevent siphoning of the water from the tank back through the shutoff valve in the event of failure of pressure in the cold water supply. It is further desirable in such hot water supply systems to vent the upper portion of the tank where the discharge outlet comprises a siphon means for automatically providing an expansion space in the upper portion of the tank accommodating expansion of the introduced cold water during the heating thereof in the tank. While a number of different vent devices have been provided in conjunction with such open-to-atmosphere heating tanks, a fully satisfactory anti-siphon and vent means has not been developed in the known prior art.

SUMMARY OF THE INVENTION The present invention comprehends a hot water supply system having improved anti-siphon and vent means for improved hot water supply by means of an open-to-atmosphere hot water tank.

More specifically, the invention comprehends the provision of a control device installed downstream of the shutoff valve of the cold water supply system which functions automatically to provide the desirable antisiphoning and venting functioning. The control device may comprise an integral valve means having a movable valve member selectively preventing backflow of liquid to the shutoff valve when the pressure in the cold water supply through the shutoff valve drops below a preselected amount. At the same time, the valve provides an opening to atmosphere from the tank for venting the tank.

When cold water is delivered to the control valve through the shutoff valve under normal pressure, the movable valve member closes the vent means and provides a continuous passage from the shutoff valve to the hot water tank inlet for normal delivery of the cold water to the tank.

The control device is extremely small and economical of construction while yet providing the highly desirable antisiponing and venting functioning discussed above. The device may be readily installed in existing installations to provide the desirable anti- BRIEF DESCRIPTION OF THE DRAWING Other features and advantages of the invention will be apparent from the following description taken in connection with the accompanying drawing wherein:

FIG. 1 is a fragmentary front elevation of a hot water supply system with an anti-siphon and vent control device embodying the invention with the heating tank shown in vertical section; and

H6. 2 is a vertical section of the anti-siphon and vent control device in aback siphon preventing and tank venting arrangement.

DESCRIPTION OF THE PREFERRED EMBODIMENT In the exemplary embodiment of the invention as disclosed in the drawing, a hot water supply system generally designated 10 is shown to comprise a hot water tank 11 provided with a siphon discharge outlet 12 having an inlet portion 13 communicating with an upper portion 14 of the space 15 within tank 11. Cold water is delivered to tank 11 from a pressurized supply source 16 through a duct means 17 provided with a conventional solenoid operated shutoff valve 18. Duct means 17 includes an end portion 19 extending through a top inlet opening 20 in the cover 21 of tank 11 for delivering cold water to the tank space 15. A guide tube 22 may be provided in the tank depending from a bracket 23 carried by cover 21 for guiding the cold water from the top space 14 downwardly .into the lower portion of tank space 15 adjacent the bottom wall 24 of the tank. A conventional electric heater 25 may be provided in the tank adjacent bottom wall 24 for heating the thusly delivered cold water. 1

The cold water delivered to the tank space 15 is heated by heater25 and expands upwardly from the level L shown in FIG. 1 through the expansion space 14. At such time, the expansion space 14 is vented to atmosphere through a control device generally designated 26 which is connected in duct 17 downstream of shutoff valve 18 by means of an intermediate duct 35.

More specifically, control device 26 includes a housing 27 defining a chamber 28 in which is movably mounted a movable valve member 29. Housing 27 includes a lower plug portion 30 threaded to a threaded port 31 and sealed to the housing by a suitable O-ring 32. The plug defines a valve seat 33 at the upper end of an inlet opening 34 to which duct 35 is connected by a conventional suitable connector 36. The housing further defines a first outlet 37 from chamber 28. A downturned elbow 38 extends from outlet 37. The housing still further defines a second outlet 39 to which duct portion 19 is connected by suitable conventional connector 40.

Valve member 29 includes a relatively heavy body 41 carrying an annular seal 42 selectively seating on valve seat 33, as shown in FIG. 2, in the venting arrangement of the valve. A guide pin 43 is mounted on an upper wall portion 44 of housing 27 to be received in an upwardly opening cylindrical recess 45 in an up-v standing tubular portion 4610f the valvemember 29. The housing defines an upper annular seat 47 against which seal 42 is urged in the flow-permitting arrangement of the valve, as shown in FIG- 1, thereby closing the vent opening 37 at that time while permitting free flow of cold water through space 28 to delivery duct portion 19 into tank 11. a

Control valve 26 is extremely simple and economical of construction while having a small overall size such as of less than approximately cubic inches. As shown, the vent is disposed above the level of the shutofi' valve 18 with the duct 35 opening upwardly to the control valve 26 to permit the gravitational control of the valve member 29 as a function of the water pressure acting upwardly against the valve member from duct portion 35.

The operation of hot water supply system 1(1) is extremely simple. When it is desired to provide hot water through outlet 12, such as to a spray head 48 (as in a coffee brewer system), the user suitably operates shutoff valve 18 to permit flow of cold water from pressure source 16 through the shutoff valve and control valve 26 into tank 11. The cold water enters the lower portion of the tank space 15 and displaces hot water up wardly to cause it to flow outwardly through outlet 12 and downwardly through spray head 48 to effect the brewing operation. The dynamic pressure of the water thus being delivered raises the weighted valve member 29 to the upper position of FIG. 1 shutting off the vent opening 37 and providing a continuous flow passage for the cold water from duct portion 35 to duct portion 19.

Upon completion of the delivery of the desired amount of cold water to tank 11, shutoff valve 18 is suitably closed thereby tenninating delivery of cold water through duct portion 35 through control device 26 and permitting the valve member 29 to move downwardly to the position of FIG. 2 wherein it sealingly seats on valve seat 33. Valve member 29 similarly seats on valve seat 33 when a low pressure or no-pressure conditions occur in the cold water supply and, thus, no water in the systemcan be back-siphoned through duct 35 and shutoff valve 18, in compliance with the code requirementsof many municipalities. At the same time, as shown in FIG. 2, valve chamber 28 becomes open to atmosphere through outlet 37 to vent the upper space 14 of tank 11 and allow a free siphoning action by the outlet siphon 12 until the level of the water in tank 11 reaches the level L at the bottom of the inlet 13 of the outlet siphon. At this point, the siphon action is broken and further delivery of hot water from tank 11 is positively terminated. The venting of the upper space 14 assures such positive siphoning and siphon termination functioning to provide an improved hot water delivery. As discussed above, the heating of the cold water in tank space 15 will cause an expansion of the cold water; however, the space 14 is preselected to accommodate the full expansion thereof so as to prevent forcing of the hot water outwardly through the outlet 12 and efi'ectively preventing drip as a result of the water expansion. The air in space 14 above the bottom of the inlet '13 is readily vented upwardly through duct 19 and control valve 26 as outlet 37 is open, as shown in FIG. 2, at this time.

Should the pressure of the cold water supply drop for some reason while shutoff valve 18 is open, the control device 26 effectively precludes any backflow of water from tank 11 as any suction action through .the valve and duct portion 35 merely more firmly urges the seal 42 against seat 33 while the valvechamber 28 remains at a mospheric pressure to positively preclude any an inlet, means for heating water in said tank, duct means for conducting cold water to said inlet, and a shutoff valve in said duct means for selectively permitting and preventing cold water flow therethrough to said tank inlet, cooperating flow control means comprising: control means in said duct means intermediate said shutoff valve and said-inlet means forselectively providing a continuous passage for conducting cold water flow from said valve therethrough to said tank inlet when said valve is arranged to permit said cold water flow, and opening said passage to atmosphere when said valve is arranged to prevent said cold water flow to vent said tank inlet and prevent back flow of water through said duct to said shutoff valve; and means defining an outlet siphon having an inlet communicating with an upper portion of the tank, said vent control means including an opening communicating between said passage and the upper portion of said tank above the level of said siphon inlet permitting free siphoning of the water from the tank down to the level of said siphon inlet in said tank.

2. The hot water supply vent means of claim 1 wherein said control means is spaced from said valve means.

3. The hot water supply vent means of claim 1 wherein said outlet syphon is open to atmosphere at all times.

4. The hot water supply, vent means .of claim 1 wherein said duct means defines a vertical portion leading to said anti-siphon means.

5. The hot water supply vent means of claim 1 wherein said control means occupies-a volume of less than approximately 15 cubic inches.

6. The hot water supply vent means of claim 1 wherein said control means includes a small valve member and weight means for gravitationally urging said valve member to the arrangement wherein said tank inlet is vented.

7. The hot water supply vent means of claim 1 wherein said anti-siphon means is disposed above the level of said shutoff valve means.

8. The hot water supply vent means of claim 1 wherein said shutoff valve includes solenoid operating means.

9. The hot water supply vent means of claim 1 wherein said control means includes a valve member responsive to the flow of cold water from the valve through the float control means to the tank inlet to close the passage to atmosphere during said flow and responsive to discontinuation of the cold .water flow to effect said opening of said passage to atmosphere.

PATENT NO. DATED Q INVENTOR(S) UNITED STATES PATENT OFFICE CERTENCATE 0F CORRECTION 699, 944 tober 24, 1972 Harvey R. Karlen It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 4,

[SEAL] Claim 1, line 16,

delete "flow" and insert anti-siphon ventafter "cooperating";

Claim 4, line 41, vent control-;

Claim 7, line 51, vent control;

Claim 7, line 52,

Arrest:

RUTH C. MASON Arresting Officer after "anti-siphon" insert after "anti-siphon" insert and after "valve" delete "means".

eighth Day of June1976 C. MARSHALL DANN Commissioner of Parent: and Trademarks

Claims

1. In a hot water supply system having a tank defining an inlet, means for heating water in said tank, duct means for conducting cold water to said inlet, and a shutoff valve in said duct means for selectively permitting and preventing cold water flow therethrough to said tank inlet, cooperating flow control means comprising: control means in said duct means intermediate said shutoff valve and said inlet means for selectively providing a continuous passage for conducting cold water flow from said valve therethrough to said tank inlet when said valve is arranged to permit said cold water flow, and opening said passage to atmosphere when said valve is arranged to prevent said cold water flow to vent said tank inlet and prevent back flow of water through said duct to said shutoff valve; and means defining an outlet siphon having an inlet communicating with an upper portion of the tank, said vent control means including an opening communicating between said passage and the upper portion of said tank above the level of said siphon inlet permitting free siphoning of the water from the tank down to the level of said siphon inlet in said tank.

4. The hot water supply vent means of claim 1 wherein said duct means defines a vertical portion leading to said anti-siphon means.

5. The hot water supply vent means of claim 1 wherein said control means occupies a volume of less than approximately 15 cubic inches.

9. The hot water supply vent means of claim 1 wherein said control means includes a valve member responsive to the flow of cold water from the valve through the float control means to the tank inlet to close the passage to atmosphere during said flow and responsive to discontinuation of the cold water flow to effect said opening of said passage to atmosphere.