Search Images Maps Play YouTube News Gmail Drive More »
Sign in
Screen reader users: click this link for accessible mode. Accessible mode has the same essential features but works better with your reader.

Patents

  1. Advanced Patent Search
Publication numberUS2696085 A
Publication typeGrant
Publication dateDec 7, 1954
Filing dateMar 31, 1952
Priority dateMar 31, 1952
Publication numberUS 2696085 A, US 2696085A, US-A-2696085, US2696085 A, US2696085A
InventorsRuff Alonzo W
Original AssigneeV C Patterson & Associates Inc
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Heat pump water heater
US 2696085 A
Abstract  available in
Images(1)
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)

Dec. 7, 1954 w RUFF HEAT PUMP WATER HEATER Filed March 51, 1952 g] iv PRESSURE REDl/G /NG DEV/CE HOT WATER COLD WA TER INVENTOR A L ONZ o W. RUFF ATTORNEY United States Patent HEAT PUMP WATER HEATER Alonzo W. Ruff, York, Pa., assignor to V. C. Patterson & Associates, Inc., York, Pa., a corporation of Pennsylvania Application March 31, 1952, Serial No. 279,703

5 Claims. (Cl. 62-4) This invention relates to heat pumps and more particularly to water heaters of the domestic type which operate on the heat pump principle.

Apparatus of this general type embodies basically, a hot water storage tank and a heat pump of the type in which a refrigerant is used as the working fluid. The heat pump itself includes a motor driven compressor, an evaporator and a condenser. The evaporator is placed in a convenient location where it is exposed to a source of heat and the condenser is disposed within the hot water storage tank. In operation, the compressor serves to withdraw gaseous refrigerant from the evaporator and compress the gaseous refrigerant thereby further raising its heat content. The hot gaseous refrigerant is then pumped through the condenser where it is changed back to liquid phase giving up its superheat, if any, plus its latent heat of condensation to the water in the tank. From this point the liquefied refrigerant is led through an expansion device to the evaporator and the cycle is repeated.

The apparatus described herein embodies several improvements over known devices of this type.

In general, the objects of this invention are to provide a heat pump water heater of improved design and operating efficiency.

The basic improvement to be described in detail herein involves a novel refrigerant circuit for the heat pump, in which a motor compressor unit having both a high discharge pressure and low discharge pressure outlet is used. The heat exchanger condenser is divided in three sections. One section is positioned in the upper portion of the hot water storage tank, a second is positioned substantially in the mid-section of the tank, and the third is located in the lower portion of the tank.

The invention may be readily understood from the following description read in conjunction with the accompanying sheet of drawings, in which:

The singl vfigure shows in diagrammatic form the basic refrigerant circuit, and arrangement of the apparatus.

Referring now to the drawing, the apparatus comprises essentially a refrigerant evaporator unit 10, a hot water storage tank 11, a motor compressor unit 12, and a con denser type heat exchanger. The evaporator may be mounted on the tank as shown, or it may be placed in any convenient location where it is in heat exchange relation with a source of heat. Conveniently, the source of heat may be a source otherwise wasted, such as waste heat from a cooking stove or chimney flue. In case of the former, the evaporator serves to cool and dehumidify the kitchen and in the latter case, the dehumidifying action is a desirable one in an otherwise damp basement. The heat exchanger includes a desuperheating coil 13 arranged in the upper part of the storage tank 11, a high temperature condenser 14 arranged at about the mid portion of the tank, and a low temperature condenser 15 located in the lower portion of the tank. The bottom of the low temperature condensing coil is connected to the evaporator unit by a conventional liquid line 16 in which is interposed an expansion valve 17. The latter may be of any of several well known types, such as, for example, a thermally controlled expansion valve. A suction line 18 connects the other side of the evaporator unit 10 to a suction inlet on the motor compressor unit WhlCl'l inlet is common to both cylinders.

The compressor unit itself in accordance with the present invention, comprises a pair of cylinders 19 and 20, the former being a high discharge pressure cylinder, and

the latter being a relatively low discharge pressure cylinder. A line 21 connects the high discharge pressure cylinder 19 to the input side of the desuperheating coil 13 and a similar line 22 connects the output of the low discharge pressure cylinder 20 to the input side of the low temperature condensing coil 15. The low temperature condenser is therefore fed jointly by the discharge from the high temperature condenser coil and the discharge from the low discharge pressure cylinder 20. A pressure reducing device 23 is interposed between the high and low temperature condensing coils above the point where the line 22 connects the low discharge pressure cylinder to the low temperature condenser. This serves to maintain a pressure differential between the high and low temperature condensing stages. In practice, the pressure reducing device may assume any one of several well known forms. For example, it may be a capillary tube, a spring loaded relief valve, or even a hand adjustable throttle valve.

In order to control the rate of transfer of heat to the water in the tank, a thermostat 24 may be located substantially at the mid-section of the storage tank in heat exchange relation to the water in the tank at that point, and is connected in series with the source of electrical supply to the motor compressor unit. A fan 25 driven by an electric motor 26 maintains a fiow of air over the evaporator unit 10, and the motor 26 is connected in parallel with the motor of the motor compressor unit so that it also will be controlled by the thermostat 24-.

In operation, therefore, inresponse to a demand for heat in the storage tank, the thermostat 24 operates to close the circuit to the motor compressor unit 12 and the fan motor 26. The motor compressor unit then supplies superheated refrigerant to coil 13 and simultaneously supplies heated gaseous refrigerant at a relatively lower temperature and pressure to the heat exchange coil 15. The refrigerant in coil 13 loses its superheatto the water in the upper portion of the tank and then flows, as a saturated gas, down to the high temperature condenser where it is partially condensed, and part of the latent heat of condensation is transferred to the water in the mid-section of the tank. The mixture of gas and liquid after passing through the pressure reducing device, then joins the heated gas from the low pressure cylinder. The resulting mixture is then circulated through the low temperature condenser coil 15 to give up the remainder of its latent heat of condensation to the water in the lower portion of the tank. From there, the cooled and liquefied refrigerant passes through the liquid line 16, the expansion valve 17 and into the evaporator unit 10. There, in changing back from liquid to gaseous state, it picks up heat from the ambient air being circulated through the evaporator coils by the fan 25. The heat laden refrigerant is then returned to a common intake of the motor compressor unit through the suction line 18, where it is recompressed and the cycle is repeated.

It has been discovered that the basic refrigerant circuit as described above yields superior results, as to operating eificiency. While the compressor shown on the attached drawing is of the piston type, it will be apparent to those skilled in the art that other well known types, such for example as rotary compressors, are readily adaptable to the apparatus herein shown and described. Also, a compressor having more than two difierent discharge pressure outlets could be used. For example, a compressor having three diiferent discharge pressure outlets could be used to feed separately, the three stages of the heat exchanger.

In addition, however, to the above described refinements in the refrigerant circuit, it has also been discovered that the waste heat of the motor compressor unit may be more effectively utilized by increasing its rate of transfer to the water in the tank. This is accomplished by certain structural modifications, a description of which follows.

Referring again to the drawing, it will be seen that the storage tank 11 is provided with a depression or pocket 27 in a side wall of the tank adjacent the upper end thereof. In practice, the motor compressor unit will be of the well known hermetically sealed type, but it in turn will be wholly received within the pocket 27 and also sealed therein. The space intermediate the motor compressor unit and the pocket is then filled with a non inflammable liquid having good heat transfer characteristics in order to increase the rate of transfer of the waste heat from the motor compressor to the warmest Water in the upper portion of the tank by conduction. One ex ample of a liquid Well adapted to this purpose is Pyranol, which is a well known oil, in common use, in oilimmersed electrical transformer apparatus. it also has high dielectric constant which is desirable to prevent short circuiting the electrical leads which carry current to the motor compressor unit.

The water in the storage tank of heaters of this type tends to stratify in definite temperature levels. The hottest water will be in the upper portion of the tank surrounding the desuperheating coil, while the water in the bottom portion of the tank surrounding the low temperature condenser coil may be only a few degrees warmer than the make up water. The water in the mid-section of the tank, surrounding the high temperature condenser will be at an intermediate temperature and these temperature strata remain fairly constant in normal operation of the apparatus. For this reason, the operating characteristics of the heat exchanger, that is, its temperature and pressure in the three sections, also remain substantially constant.

The foregoing will enable one skilled in the art to fully understand the invention and the novelty thereof which is defined by the following claims.

I claim:

1. A water heater of the heat pump type, comprising in combination: a hot water storage tank; a refrigerant evaporator adapted to absorb heat from the atmosphere; heat transfer means of the type in which refrigerant is circulated, said means being disposed in heat exchange relation to the water in said tank, extending substantially from top to bottom thereof and including during normal operating conditions, a desuperheating stage located adjacent the upper part of said tank, a high temperature condensing stage located substantially at the mid-section of said tank, and a low temperature condensing stage located adjacent the bottom part of said tank said stages being connected in series; means connected between said high and low temperature stages to maintain a controlled pressure differential therebetween; means connecting said low temperature condensing stage to said evaporator, said means including an expansion device; motor driven refrigerant compression means, said means including at least a low discharge pressure outlet and a high discharge pressure outlet; a common suction inlet for said compression means; means connecting said high discharge pressure outlet to said desuperheating stage; means connecting said low discharge pressure outlet to said low temperature condensing stage; means connecting said evaporator to the suction inlet of said compressor; and means responsive to the temperature of the water in said tank to control the transfer of heat thereto.

2. A water heater of the heat pump type, comprising in combination: a hot Water storage tank; a refrigerant evaporator adapted to absorb heat from the atmosphere; heat transfer means of the type in which refrigerant is circulated, said means being disposed in heat exchange relation to the water in said tank, extending substantially from top to bottom thereof and including during normal operating conditions, a desuperheating stage located adjacent the upper part of said tank, a high temperature condensing stage located substantially at the mid-section of said tank, and a low temperature condensing stage located adjacent the bottom part of said tank said stages being connected in series; means connected between said high and low temperature stages to maintain a controlled pressure differential therebetween; means connecting said low temperature condensing stage to said evaporator, said means including an expansion device; a motor compressor unit, said compressor including a low discharge pressure cylinder and a high discharge pressure cylinder; a suction inlet to said compressor common to both said cylinders; means connecting said high discharge pressure cylinder to said desuperheating stage; means connecting said low discharge pressure cylinder to said low temperature condensing stage; means connecting said evaporator to the suction inlet of said compressor; and means responsive to the temperature of the water in said tank to control the transfer of heat thereto.

3. A water heater as defined by claim 1 in which the motor compressor unit is mounted on and in heat exchange relation to said storage tank.

4. A water heater as defined by claim 1 in which said storage tank is formed with a depressed pocket in the side wall thereof adjacent the upper portion thereof; means sealing said motor compressor unit within said pocket; and a noninfiammable liquid having a high dielectric constant interposed in the space intermediate said compressor unit and said storage tank to increase the rate of heat transfer from said motor compressor to the water in said tank.

5. In a water heater of the heat pump type, a heat pump comprising: a motor compressor unit, said compressor including a low discharge pressure cylinder and a high discharge pressure cylinder; a suction inlet to said compressor common to both said cylinders; an evaporator; a condenser type heat exchanger; conduit means connecting the high discharge pressure cylinder of said motor compressor unit to one end of said heat exchanger; conduit means including an expansion device connecting the opposite end of said heat exchanger to said evaporator; conduit means connecting the low discharge pressure cylinder of said motor compressor unit to an intermediate point on said heat exchanger; means connected to said heat exchanger for maintaining a controlled pressure differential between that portion of the heat exchanger to which the high discharge pressure cylinder is connected and that portion to which the low discharge pressure cylinder is connected; and further conduit means connecting said evaporator to the suction inlet of said motor compressor.

References Cited in the file of this patent UNITED STATES PATENTS

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US2104974 *Jun 15, 1936Jan 11, 1938Bailey P DawesFuel heater for internal combustion engines
US2463881 *Jul 6, 1946Mar 8, 1949Muncie Gear Works IncHeat pump
US2500688 *Aug 24, 1948Mar 14, 1950Edward P KellieRefrigerating apparatus
US2516093 *May 5, 1949Jul 18, 1950V C Patterson & Associates IncHeat pump water heater and method of heat exchange
US2516094 *May 17, 1949Jul 18, 1950V C Patterson & Associates IncHeat pump water heater
US2597745 *Sep 29, 1948May 20, 1952Sunroc Refrigeration CompanyRefrigerator and stove
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2802342 *Jan 20, 1955Aug 13, 1957 Heat pumps
US2968934 *Feb 28, 1958Jan 24, 1961Heat Pump & Refrigeration LtdHeat pump systems
US3244010 *Nov 23, 1962Apr 5, 1966Martin William FTemperature dependent density gradient
US4146089 *Aug 12, 1977Mar 27, 1979Paul Mueller CompanyHot water system and condensing unit therefor
US4173872 *Feb 1, 1978Nov 13, 1979Energy Utilization Systems, Inc.Water heater apparatus
US4216660 *May 4, 1978Aug 12, 1980T.E.S., Inc.Heat generator
US4389857 *Aug 21, 1980Jun 28, 1983Genvex Energiteknik A/SHeat exchanger
US4448347 *Dec 9, 1981May 15, 1984Dunstan Phillip EHeat pump system using wastewater heat
US4474018 *May 6, 1982Oct 2, 1984Arthur D. Little, Inc.Heat pump system for production of domestic hot water
US4517799 *Dec 7, 1983May 21, 1985Misawa Home Co., Ltd.Heat utilizing system using internal combustion engine
US4747273 *Mar 5, 1987May 31, 1988Artesian Building SystemsHeating and cooling system
US4798240 *Mar 18, 1985Jan 17, 1989Gas Research InstituteIntegrated space heating, air conditioning and potable water heating appliance
US4959975 *May 14, 1987Oct 2, 1990Conserve, Inc.Heat pump system
US5906109 *Jul 3, 1998May 25, 1999Arthur D. Little, Inc.Heat pump water heater and storage tank assembly
US5946927 *Apr 14, 1998Sep 7, 1999Arthur D. Little, Inc.Heat pump water heater and storage tank assembly
US6290142 *Mar 23, 2000Sep 18, 2001Honda Giken Kogyo Kabushiki KaishaCogeneration apparatus
US6595011May 2, 2002Jul 22, 2003Linda Forgy ChaneyWater cooled air conditioner
US7334419 *Aug 17, 2005Feb 26, 2008Bradford White CorporationHeat pump water heater
US7748227 *Sep 16, 2005Jul 6, 2010Panasonic CorporationHeat-pump-type hot water supply apparatus
US7866168Jan 11, 2011Bradford White CorporationHeat pump water heater
US8385729Dec 9, 2009Feb 26, 2013Rheem Manufacturing CompanyHeat pump water heater and associated control system
US20060191495 *Jul 1, 2004Aug 31, 2006Ting SunAir heat pump type hot water stove
US20070039341 *Aug 17, 2005Feb 22, 2007Bradford White CorporationHeat pump water heater
US20070214816 *Sep 16, 2005Sep 20, 2007Matsushita Electric Industrial Co., Ltd.Heat-pump-type hot water supply apparatus
US20080104986 *Jan 8, 2008May 8, 2008Bradford White CorporationHeat pump water heater
US20110061418 *Feb 12, 2010Mar 17, 2011Panasonic CorporationHeat pump type hot-water heater
CN102022769A *Feb 26, 2010Apr 20, 2011松下电器产业株式会社Heat pump type hot-water heater
DE1027216B *Apr 4, 1955Apr 3, 1958Borsig AgVerfahren und Vorrichtung zum Betrieb einer Waermepumpe
DE1102187B *Mar 5, 1958Mar 16, 1961Heat Pump & Refrigeration LtdWaermepumpenanlage
DE1107682B *Apr 21, 1959May 31, 1961Minnesota Mining & MfgBehaelter zum Speichern, Erwaermen und Kuehlen von Fluessigkeiten mittels einer thermoelektrischen Waermepumpe
DE1174339B *Oct 26, 1960Jul 23, 1964Schiff & Stern Ges M B HMotoraggregat fuer nach dem Waermepumpen-prinzip arbeitende Kaeltemaschinen fuer Kuehlschraenke
WO1981000616A1 *Aug 21, 1980Mar 5, 1981Genvex Energiteknik AsHeat exchanger
WO2008094152A1 *Feb 1, 2007Aug 7, 2008Cotherm Of America CorporationHeat transfer system and associated methods
WO2009049612A2 *Oct 20, 2008Apr 23, 2009Solarhybrid AgHeat accumulator for storing thermal energy and method for shifting thermal energy in a heat accumulator
WO2009049612A3 *Oct 20, 2008Jun 11, 2009Dirk DrewsHeat accumulator for storing thermal energy and method for shifting thermal energy in a heat accumulator
Classifications
U.S. Classification62/184, 62/506, 165/61, 62/238.6
International ClassificationF24H4/00, F24H4/04
Cooperative ClassificationF24H4/04
European ClassificationF24H4/04