US2527308A - Water cooler protective system - Google Patents

Water cooler protective system Download PDF

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US2527308A
US2527308A US39787A US3978748A US2527308A US 2527308 A US2527308 A US 2527308A US 39787 A US39787 A US 39787A US 3978748 A US3978748 A US 3978748A US 2527308 A US2527308 A US 2527308A
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water
valve
solenoid
water cooler
contacts
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Expired - Lifetime
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US39787A
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Jackson Joseph Gray
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SUNROC REFRIGERATION Co
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SUNROC REFRIGERATION Co
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25DREFRIGERATORS; COLD ROOMS; ICE-BOXES; COOLING OR FREEZING APPARATUS NOT OTHERWISE PROVIDED FOR
    • F25D23/00General constructional features
    • F25D23/12Arrangements of compartments additional to cooling compartments; Combinations of refrigerators with other equipment, e.g. stove
    • F25D23/126Water cooler
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25DREFRIGERATORS; COLD ROOMS; ICE-BOXES; COOLING OR FREEZING APPARATUS NOT OTHERWISE PROVIDED FOR
    • F25D29/00Arrangement or mounting of control or safety devices

Definitions

  • My invention relates to protective devices for water coolers.
  • a purpose of the invention is to avoid damage to a building and its furnishings and equipment due to flooding from a, water cooler.
  • a further purpose is to cut off flow of water in a water cooler whenever an electric circuit is completed between protective contacts in a catch basin below the water-holding portion of.
  • a further purpose' is to provide a normally open solenoid valve in an inlet pressure line to a water cooler, and to close the valve whenever sensing elements indicate overflow of water.
  • Figure 1 is a side elevation, largely diagrammatic, of a water cooler to which my invention has been applied.
  • Figure 2 is a fragmentary transverse section across the sensing contactsin the drip-basin.
  • Figure 3 is a circuit diagram.
  • Figure 4 is a circuit diagram showing a tion.
  • Fatigue failure of metallic parts in the presence of vibration may result, such vibration being caused either by the water cooler itself or by adjacent machineryfiFailure of the temperature controlsof the Water cooler may cause freezing, in which case bursting of .tanks, piping or fittingsdue tosuch freezing'is' likely toresult.
  • I j Failures of the character mentioned which have resulted in overflow ofiwater' coolers have been sufilcientlyfrequent in some localities so that city ordinances or regulations of individual companies or buildings have restricted the use of water coolers and drinking fountains connect ed to pressure water sources;
  • the present invention is designed to reduc or eliminate the difliculty from flooding in case a Water cooler overflows from any cause, and particularly to restrict the amount of water available to cause damage by preventing flow of additional water into the system until the failure is corrected.
  • a conventional water cooler or drinking fountain comprising a cabinet 20, suitably of rectangular form, and including a water storage compartment 2
  • Suitable heat insulation is usually employed.
  • a safety valve 21 which is normally open as 1ater explained
  • a float valve 28'controlled'by a float 29 and thence discharging into the water storage tank.
  • V Discharge of water from the water storage tank is accomplishedthrough a pipe 3% to a dis.- an 3!, here shownas a faucet, rather than a bubbler which is sometimes used; Waste water is received by a catchibasin 32.
  • a downwardly directed portion. 33' of the pipe 30 below the fan cet prevents complete emptying of the water storage compartment-under normal operation, so that sufficient .waterlremains to'function as' a sweet wate'r' 'bath "to aid "in cooling incoming water.
  • the mechanical refrigeration system may be of any siiitable'type,here shown as a hermetic motor-compressor unit 34 supported on a cross rib 35 of the cabinet.
  • High pressure refrigerant such as freon passes through'a pipe 36 to a static air condenser 31 contained in a vertical air flue 38.
  • a constrictor 39 which may be an expansion valve or capillary tube, to an evaporator or'cooling unit 40, conveniently. located in the food compartment; Cooling of the water is acveniently provided in the food compartment.
  • a drip basin 44 Suitably located at any convenient point below the water carrying parts of the equipment and desirably extending out fully to the outside of the cabinet so that it will catch water overflowing due to bursting of pipes, fittings or tanks, is a drip basin 44 sloping downwardly from the'outer edges to a sump 45 which preferably constitutes the lowest point of the drip basin.
  • sensing elements 46 suitably in the form of metallic contact buttons mounted on insulating bushings 48 and spaced at 49 by a small distance which is suflicient to assure that no current will flow under the low voltage when the sump is dry, but which will permit flow of current when the sump fills with water from any cause.
  • the normally open valve 21 comprises a valve element 58 cooperating with a valve seat and having a valve stem 52.
  • a spring abutment 53 on the valve stem is urged by a spring '54 to the open position of the valve, so that the safety valve normally remains open.
  • a solenoid 55 0perates on an armature 56 on the valve stem, to close the valve when the solenoid is energized.
  • the solenoid 55 is in series with a relay switch 51' across a suitable source of electric current 58 such as a commercial alternating current source at 110 volts and 60 cycles.
  • the relay is normally open and is biased toward opening by a suitable spring not shown.
  • the primary 59 of a step down transformer is also connected across the line and a low voltage secondary 60 of the transformer is in series with the sensing contacts 46 and 4'! and the electromagnetic winding SI of the relay.
  • the thermostatic control element 62 of the refrigeration equipment suitably of the expanding and contracting liquid type, controls a bellows 63 which on expansion closes a switch 64 in series with the motor 34 of the hermetic motor-compressor unit, across the line.
  • the protective device does not function unless some abnormal condition causes water to collect in the sump.
  • the secondary circuit of the transformer is completed through the contacts and the relay is energized to close the relay switch 51, thus energizing the solenoid to cause the solenoid valve 21 to close, thus cutting on the flow of water from the pressure source.
  • the relay will open and the solenoid valve will accordingly open and permit normal functioning of the water system.
  • suitable openings or louvers 65 are provided in the cabinet to assure that water leaking down the sides of the cabinet will enter the interior and affect the protective system.
  • FIG. 4 illustrates a circuit diagram for a mechanism of this character.
  • the safety valve 21' is normally closed, the valve element being urged toward closing position by a spring 54 surrounding the valve stem 52.
  • is reversed with respect to the valve seat in Figure 3.
  • the low voltage secondary of the transformer is connected in series with the solenoid 55, which is also in series with a float switch 66 operating from a float 61 in the water storage compartment 2
  • the sensing elements 46 are suitably shunted across the solenoid.
  • a refrigerated dispensing unit having a connection to a source of water, a valve in the connection, an operating solenoid for the valve, a catch basin below the dispensing unit, spacedcontacts in communication with the basin, a source of current connected to the contacts, and electrical means in circuit with the solenoid, the contacts and the source of current for closing the valve when the presence of water between the contacts permits the current to flow.
  • a refrigerated dispensing unit having a connection to a source of water, a normally open valve in the connection, a drip basin below the dispensing unit, spaced contacts in communication. with the basin, a source of current connected to the contacts and electrical means interposed between the contacts and the source of current for closing the valve when the presence of water between the contacts'permits the current to flow.
  • a refrigerated dispensing unit having a connection to a source of water, a valve in the connection, a solenoid for closing the valve, biasing means for maintaining the valve open, a drip basin below the dispensing unit, spaced contacts in communication with the basin, a source of current connected to the contacts, and electrical connections interposed between the contacts, the source of current and the solenoid for closing the valve when the presence of water between the contacts permits current to flow.
  • a refrigerated dispensing unit having connection toa source of water, a valve in the connection, a solenoid operatively connected to the valve, a float switch, electrical means including a circuit for energizing the solenoid under normal conditions when the float switch closes, andspaced electric contact elements connected in the circuit, and adapted to permit current flow through water therebetween to render the electrical means inoperative when an emergency condition exists.
  • a refrigerated dispensing unit having a connection to a source of water, a normally closed valve in the connection, a solenoid for opening the valveyelectrical means including a circuit for energizing the solenoid at intervals to admit water and spaced electric contact elements connected in the circuit, and adapted to permit current flow through water therebetween, to render the solenoid inoperative when an emergency condition exists.
  • a refrigerated dispensing unit having a connection to a source of water, a normally closed valve in the connection, a solenoid for opening the valve, a water storage chamber connected to receive water from the valve, a float switch responding to the level of water in the chamber, electrical means for energizing the solenoid under normal conditions when the float switch is closed, a drip basin below the dispensing unit, and spaced contacts in communication with the drip basin and electrically connected in shunt across the solenoid.

Description

J. G. JACKSON Oct. 24, 1950 WATER COOLER PROTECTIVE SYSTEM Filed July 20, 1948 Patented Oct. 24, 1950 UNITED, .STATES PATENT? [OFFICE I 2,527,308 v 4 I I WATER COOLER PROTECTIVE SYSTEM v I J Joseph Gray Jackson, Bala Cynwyd, Pa., assignor v a Q to Sunroc Refrigeration Company, Dover, Del.,v a corporation of Delaware Application July 29, 1948, Serial No. 39,787
6 Claims.
My invention relates to protective devices for water coolers. Y
' A purpose of the invention is to avoid damage to a building and its furnishings and equipment due to flooding from a, water cooler.
A further purpose is to cut off flow of water in a water cooler whenever an electric circuit is completed between protective contacts in a catch basin below the water-holding portion of. the
cooler. e I a A further purpose'is to provide a normally open solenoid valve in an inlet pressure line to a water cooler, and to close the valve whenever sensing elements indicate overflow of water.
Further purposes appear in the specification and in the claims.
In the drawings I 'haVe chosento illustrate a few only of the numerouslembodiments in which my invention may appear, choosing the forms shown from the standpoints of convenience in illustration, satisfactory operation and clear demonstration of the principles involved.
Figure 1 is a side elevation, largely diagrammatic, of a water cooler to which my invention has been applied. V
Figure 2 is a fragmentary transverse section across the sensing contactsin the drip-basin.
Figure 3 is a circuit diagram. Figure 4 is a circuit diagram showing a tion.
Describing in illustration but not in limitation and referring to the drawings:
Especially in large office buildings and in industrial plants employing complicatedmachinvariaery, havoc has been Wrought from time to time when something has gone, wrong with awater cooler or drinking fountain so as to cause'it to overflow. Bursting or other failure of a mechanically refrigerated Water cooler can occur from a number-of causes. Metallic or fabrication defects can cause piping, tanks or fittings to leak. Pressure can cause bursting of components. This is especially likely to oc-cur'in high office buildings, wheresurges of excessive pressure are likely to'be encountered inthefwater piping system. Fatigue failure of metallic parts in the presence of vibration may result, such vibration being caused either by the water cooler itself or by adjacent machineryfiFailure of the temperature controlsof the Water cooler may cause freezing, in which case bursting of .tanks, piping or fittingsdue tosuch freezing'is' likely toresult. iv I j Failures of the character mentioned which have resulted in overflow ofiwater' coolers have been sufilcientlyfrequent in some localities so that city ordinances or regulations of individual companies or buildings have restricted the use of water coolers and drinking fountains connect ed to pressure water sources;
The present invention is designed to reduc or eliminate the difliculty from flooding in case a Water cooler overflows from any cause, and particularly to restrict the amount of water available to cause damage by preventing flow of additional water into the system until the failure is corrected.
As shown in the drawings, a conventional water cooler or drinking fountain is illustrated, comprising a cabinet 20, suitably of rectangular form, and including a water storage compartment 2| at one side of thetop, a, food storage compartment 22 at the other side of the top, separated fromthe water storage compartment by a suitable metallic partition 23, and a mechanical compartment 24in the lower portion separated from the water and food storage compartmentsby a partition'25. Suitable heat insulation; not shown," is usually employed.
The water systemrincludes 'apressure connection 28 to a public drinking water system, feeding into a safety valve 21,-which is normally open as 1ater explained; and then through a float valve 28'controlled'by a float 29 and thence discharging into the water storage tank. When a suitable level is reached in the water storage tank, introduction of water is cut oif by closing of the float vvalve as well known. V Discharge of water from the water storage tank is accomplishedthrough a pipe 3% to a dis.- penser 3!, here shownas a faucet, rather than a bubbler which is sometimes used; Waste water is received by a catchibasin 32. A downwardly directed portion. 33' of the pipe 30 below the fan cet prevents complete emptying of the water storage compartment-under normal operation, so that sufficient .waterlremains to'function as' a sweet wate'r' 'bath "to aid "in cooling incoming water.
The mechanical refrigeration system may be of any siiitable'type,here shown as a hermetic motor-compressor unit 34 supported on a cross rib 35 of the cabinet. High pressure refrigerant such as freon passes through'a pipe 36 to a static air condenser 31 contained in a vertical air flue 38. "From the condenser the refrigerant passes through a constrictor 39, which may be an expansion valve or capillary tube, to an evaporator or'cooling unit 40, conveniently. located in the food compartment; Cooling of the water is acveniently provided in the food compartment.
From the evaporator the refrigerant returns to the suction side of the compressor through a pipe 43.
Suitably located at any convenient point below the water carrying parts of the equipment and desirably extending out fully to the outside of the cabinet so that it will catch water overflowing due to bursting of pipes, fittings or tanks, is a drip basin 44 sloping downwardly from the'outer edges to a sump 45 which preferably constitutes the lowest point of the drip basin. Conveniently located in the sump are sensing elements 46, suitably in the form of metallic contact buttons mounted on insulating bushings 48 and spaced at 49 by a small distance which is suflicient to assure that no current will flow under the low voltage when the sump is dry, but which will permit flow of current when the sump fills with water from any cause.
The normally open valve 21 comprises a valve element 58 cooperating with a valve seat and having a valve stem 52. A spring abutment 53 on the valve stem is urged by a spring '54 to the open position of the valve, so that the safety valve normally remains open. A solenoid 55 0perates on an armature 56 on the valve stem, to close the valve when the solenoid is energized. The solenoid 55 is in series with a relay switch 51' across a suitable source of electric current 58 such as a commercial alternating current source at 110 volts and 60 cycles. The relay is normally open and is biased toward opening by a suitable spring not shown. The primary 59 of a step down transformer is also connected across the line and a low voltage secondary 60 of the transformer is in series with the sensing contacts 46 and 4'! and the electromagnetic winding SI of the relay. The thermostatic control element 62 of the refrigeration equipment, suitably of the expanding and contracting liquid type, controls a bellows 63 which on expansion closes a switch 64 in series with the motor 34 of the hermetic motor-compressor unit, across the line.
In operation the protective device does not function unless some abnormal condition causes water to collect in the sump. When this condition develops, the secondary circuit of the transformer is completed through the contacts and the relay is energized to close the relay switch 51, thus energizing the solenoid to cause the solenoid valve 21 to close, thus cutting on the flow of water from the pressure source. As long as water remains in the sump, the flow will be cut ofi, but whenever the difliculty has been corrected and the water removed from the sump, the relay will open and the solenoid valve will accordingly open and permit normal functioning of the water system.
It will thus be evident that even in case of a freeze-up and bursting of'the water storage tank the maximum amount of water available to cause damage is the water present in the tank and associated piping.
In case there is danger that water will be discharged externally and may not aifect the protective system quickly enough, suitable openings or louvers 65 are provided in the cabinet to assure that water leaking down the sides of the cabinet will enter the interior and affect the protective system.
In some cases where a solenoid valve is being employed for another purpose, as to control the admission of water into the water cooler under the regulation of a liquid level device such as a float switch, it may be desirable to employ the same solenoid valve as a safety device in accordance with the present invention. Figure 4 illustrates a circuit diagram for a mechanism of this character. In this instance the safety valve 21' is normally closed, the valve element being urged toward closing position by a spring 54 surrounding the valve stem 52. The valve seat 5| is reversed with respect to the valve seat in Figure 3.
In this case the low voltage secondary of the transformer is connected in series with the solenoid 55, which is also in series with a float switch 66 operating from a float 61 in the water storage compartment 2|, thus eliminating the necessity for the float valve 28 in this form. The sensing elements 46 are suitably shunted across the solenoid.
Thus in operation when the water level falls the float 6'! falls and closes the float switch 66 which under normal operating conditions will cause current to pass through the solenoid 5'5 and open the solenoid valve against'the action of the spring 54' for a time long enough to fill the water storage compartment and permit the float switch to again open. As soon as the float switch opens the valve 21' returns to its normaly closed condition. In case an emergency condition develops, water will short circuit the gap between the sensing elements 46, thus shunting the solenoid 55. Accordingly even though the float 81 may fall due to the leakage of water from the water storage compartment, and even though the float switch 66 may close, the solenoid valve will remain closed since the solenoid is shunted by the sensing elements. Thus it is not possible for the float switch to cause water to enter through the solenoid valve as long as the emergency condition continues. Whenever the emergency is corrected and water is removed from between the sensing elements, the water cooler can function in the normal manner.
In view of my invention and disclosure variafi tions and modifications to meet individual whim or particular need will doubtless become evident to others skilled in the art, to obtain all or part of the benefits of my invention without copying the structure shown, and I, therefore, claim all such insofar as they fall within the reasonable spirit and scope of my claims.
Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:
1. In a water cooler, a refrigerated dispensing unit having a connection to a source of water, a valve in the connection, an operating solenoid for the valve, a catch basin below the dispensing unit, spacedcontacts in communication with the basin, a source of current connected to the contacts, and electrical means in circuit with the solenoid, the contacts and the source of current for closing the valve when the presence of water between the contacts permits the current to flow.
2. In a water cooler, a refrigerated dispensing unit having a connection to a source of water, a normally open valve in the connection, a drip basin below the dispensing unit, spaced contacts in communication. with the basin, a source of current connected to the contacts and electrical means interposed between the contacts and the source of current for closing the valve when the presence of water between the contacts'permits the current to flow.
3. In a water cooler, a refrigerated dispensing unit having a connection to a source of water, a valve in the connection, a solenoid for closing the valve, biasing means for maintaining the valve open, a drip basin below the dispensing unit, spaced contacts in communication with the basin, a source of current connected to the contacts, and electrical connections interposed between the contacts, the source of current and the solenoid for closing the valve when the presence of water between the contacts permits current to flow.
4. In a water cooler, a refrigerated dispensing unit having connection toa source of water, a valve in the connection, a solenoid operatively connected to the valve, a float switch, electrical means including a circuit for energizing the solenoid under normal conditions when the float switch closes, andspaced electric contact elements connected in the circuit, and adapted to permit current flow through water therebetween to render the electrical means inoperative when an emergency condition exists.
5. In a water cooler, a refrigerated dispensing unit having a connection to a source of water, a normally closed valve in the connection, a solenoid for opening the valveyelectrical means including a circuit for energizing the solenoid at intervals to admit water and spaced electric contact elements connected in the circuit, and adapted to permit current flow through water therebetween, to render the solenoid inoperative when an emergency condition exists.
6. In a water cooler, a refrigerated dispensing unit having a connection to a source of water, a normally closed valve in the connection, a solenoid for opening the valve, a water storage chamber connected to receive water from the valve, a float switch responding to the level of water in the chamber, electrical means for energizing the solenoid under normal conditions when the float switch is closed, a drip basin below the dispensing unit, and spaced contacts in communication with the drip basin and electrically connected in shunt across the solenoid.
JOSEPH GRAY JACKSON.
REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS Name Date Number Ritter Aug. 6, 1946
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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2765631A (en) * 1952-07-16 1956-10-09 Milwaukee Gas Specialty Co Control apparatus for fluid fuel burning apparatus and the like
US3216499A (en) * 1963-07-01 1965-11-09 Pan American Petroleum Corp Fusible bottom-hole igniter
US6041611A (en) * 1998-08-20 2000-03-28 Palmer; James R. System and method for cleaning air conditioning drains
US20150121924A1 (en) * 2012-06-12 2015-05-07 Bsh Bosch Und Siemens Hausgeraete Gmbh Refrigeration appliance with a monitoring device

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2405448A (en) * 1945-01-13 1946-08-06 Westinghouse Electric Corp Refrigerating apparatus

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2405448A (en) * 1945-01-13 1946-08-06 Westinghouse Electric Corp Refrigerating apparatus

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2765631A (en) * 1952-07-16 1956-10-09 Milwaukee Gas Specialty Co Control apparatus for fluid fuel burning apparatus and the like
US3216499A (en) * 1963-07-01 1965-11-09 Pan American Petroleum Corp Fusible bottom-hole igniter
US6041611A (en) * 1998-08-20 2000-03-28 Palmer; James R. System and method for cleaning air conditioning drains
US20150121924A1 (en) * 2012-06-12 2015-05-07 Bsh Bosch Und Siemens Hausgeraete Gmbh Refrigeration appliance with a monitoring device
US10415877B2 (en) * 2012-06-12 2019-09-17 Bsh Hausgeraete Gmbh Refrigeration appliance with a monitoring device

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