US2490983A

US2490983A - Heat pump

Info

Publication number: US2490983A
Application number: US713504A
Authority: US
Inventors: Marvin M Smith; Emory N Kemler
Original assignee: MUNCIE GEAR WORKS Inc
Current assignee: MUNCIE GEAR WORKS Inc
Priority date: 1946-12-02
Filing date: 1946-12-02
Publication date: 1949-12-13
Anticipated expiration: 1966-12-13

Description

D@.113,1949 M. M. SMHTH ETAL m wg HEAT PIMP I Filed Dec. 2 1946 2 Sheets-Sheet l RECEIVER INVENTORS MARVIN M. SMITH MORY N. KEMLEI'R BY QM 29% ATTORNEYS Dec. 33, 11949 M S r 2,4,9

HEAT PUMP Filed Dec. 2, 1946 2 She'ets-Shet 2 HEAT EXGHANGER 3 INVENTORS MARVIN M. SMITH ATTORNEYS EMORY N. KEMLER Patented Dec. 13, 1949 HEAT PUMP Marvin M. Smith, Munele, Ind., and Emory N.

Kemler, Birmingham, Ala., assignors to Muncie Gear Works, Inc., Munclc, Ind., a corporation oi Indiana Application December 2, 1946, Serial No. 713,504

Claims. 1

This invention relates to heat pumps, and particularly to improvements in deep well devices for utilizing subterranean temperatures as a source of heat. Reference is here made to the copending application of Marvin M. Smith, Serial No. 624,351, filed October 25, 1945, with respect to which the present invention embodies specific improvements.

The main object of the present invention is to provide improved means for utilizing deep well water as a source of heat in a heat pump and prevent a condition in which the water standing in the well tends to approach the temperature of the water in a closed circulatory system so closely that heat-transfer to or from the closed system is retarded; and to provide improved means whereby, under certain conditions, water standing in the well is withdrawn so that its pressure head is reduced and water from around the well flows in.

A further object of the invention is to provide means for automatically discharging water from the well to waste when such water has acquired a temperature near that of equilibrium with the temperature of the circulatory system of the heat pump.

Certain specific embodiments of this invention are illustrated in the accompanying drawings in which:

Fig. 1 is a diagrammatic representation of a heat pump with closed conduit for circulating a heat conveying medium to and from a deep well according to the present invention.

Fig. 2 is a fragmentary diagrammatic view of a modified form of the same.

Fig. 3 is a fragmentary diagram of a further modification of the same.

In the form shown in Fig. 1, the heat pump comprises the usual reversible refrigeration cycle apparatus including a compressor l, a pair of heat-exchangers serving in the heating season as condenser 2 and evaporator 3, a receiver 4 and expansion valve 5 connected in a closed system for circulating a refrigerant. The condenser 2 and evaporator 3 may be coils carrying the refrigerant and coupled in heat-exchange relation with coils 6 and 1, respectively, forming part of a conduit for circulating a heat conveying medium in a closed circuit with a loop of piping 8 that is submerged in a deep well 9 communicating with a source of subterranean water whose normal surface level, below the surface it of the earth, is indicated at H.

The upward or out-going lead l2 of the loop 8 is connected to a pump l3 which in turn is connected by a three-way valve It with a pipe I! leading to the coil 6 and with a pipe l6 leading to the coil I. The coils 6 and I are connected by pipes l1 and I8 to the return lead I! of the loop 8. The position of the lever 20 of the three-way valve determines the direction of flow of water from the pipe l2 to the pipe l5 or l6 respectively.

As is usual in the use of heat pumps for heating or cooling a space, air to be heated is directed over the condenser coil 2 during the heating season, as indicated in the diagram by the arrow 21; and during cooling season, the air current is directed over the evaporator coil 3, as indicated by the arrow 22 in Fig. 1.

During the heating season, the water in the deep well serves as a source of heat which is supplied to the evaporator coil 3 through pipes 42 and I6, coil I, and pipes l8 and i9, when the circulating pump l3 and refrigeration cycle apparatus are in operation, as for example,to heat air exposed to the condenser.

During the pooling season, the deep well serves as a dump for heat delivered to the circulating medium by the condenser after being extracted from the air by the evaporator of the heat pump. In such operation, the coil 6 absorbs the heat from the condenser coil 2 and the conduit carries it to the well 9 through pipes II and H, the circulating medium being cooled in the well, and is returned by pipe l2, pump l3 and pipe IE to the coil 6 in a closed circuit of flow. In the apparatus shown, the three-way valve I4 controls the circulation of this heat-conducting medium to render the coil 1 operative and the coil 6 inoperative during the heatin season, in one position of the handle or arm 20; and another position of said handle 20 renders the coil 6 cperative and the coil 1 inoperative in the conduction of the heating medium.

In the form shown in Fig. 1, the operation of the deep well as a heat exchanger for either heating or cooling the circulating medium in the loop 8 is intensified by circulating the water of the well.

To this end a pipe 23 extends from a point in the well below the normal ground water level to a pump 24, thence through pipe 25 to a tubular casing 26 which surrounds the return lead it of the loop 8 and delivers'the contents of said casing close to the bottom of the well. A branch pipe 21 leads from the pump-24 to waste. The discharge through this waste pipe is controlled by a 3 valve 28 which is normally closed but may be opened by a solenoid which in turn is controlled by a thermostat 30 preferably located near the well so as to be sensitive to changes in temperature in the water; of the well as reflected by the temperature in the pipe 12.

The thermostat 30 operates-a suitable relay H which closes the normally open switch 32 to supply current to the solenoid 28 from

line conductors

33 and 34. The switch element 35 controlled by the thermostat 30 controls the operation oi the relay 3|, as will be understood from the electrical connections, as diagrammatically indicated in Fig. l.

Inasmuch as the present invention relates mainly to the use of the deep well as a heat exchanger acting between the subterranean earth temperature and the temperature of one or the other of the heat exchangers of the refrigeration cycle of the heat pump, it is thought to be suil'icient for the disclosure of the present invention to confine the drawings and description to such parts of the heat pump apparatus as are directly involved in the function and operation of the deep well equipment. Suitable apparatus for reversibly operating the refrigeration cycle is more fully described in Patent No. 2,401,890, issued to Muncie Gear Works, Inc. as assignee of Smith, Fields and Kemler.

The operation of the device shown in Fig. l is as follows:

When the heat pump is operating for heating the air of a building, the air flow will be directed over the condenser coils 2, as indicated by the arrow 2i and the evaporator coil will be isolated from such air flow by its closed housing indicated at 36, the lever 20 will be thrown into the position in which it is shown in full lines in Fig. l, so that the conduit which carries the circulating heatconducting medium to and from the deep well mitted to the refrigerant flowing in coil 3 of theevaporator., The temperature of this heat is intensified through the action of the compressor and utilized in the condenser for the heating function. a

In the normal operation of the heat pump. during the heating season, the time period of continuous operation is relatively short and seldom is it so prolonged that the temperature of the standing water in the well reaches a point where the water or other circulating'medium passing through the loop 8 fails to pick up an 'eilfective quantity of heat from the well forproper operation of the heat pump. Such a condition of equilibrium might be wasteful of power or might be titherwise detrimental.

'In periods between intervals ofoperation, both the fluid in the closed system and that in the well bore have a chance to closely. approach the earth temperature. However, in long periods of operation which occur in extremely cold weather con.- ditions, usually experienced only a few times during the heating season, the operation of the heat pump may be almost continuous. Under these conditions, thefluid in the well will not have a chance to store up suillcient heat for the most eflicient operation of the heat pump.

In order to prevent the occurrence oi such undesirable operating conditions, the present invention provides means for automatically discharging some or the well water to waste so as to cause a fresh supply of water to flow from the earth reservoir into the well bore to replace that discharged to waste. The fluid brought in by this action will be at earth temperature and will assure a proper temperature in the well bore to cause it to function properly as a source of heat in its heat exchange relation to the circulating medium.

When in the heating season the circulating water temperature reaches a predetermined low value for which the thermostat 30 has been set to close the switch 35, this will cause relay 3! to close its switch 32 and actuate the solenoid 2! to open valve 28, so as to discharge water to waste through pipe 21. The valve 28 being normally urged to a closed position will cut off this waste i when the temperature within the pipe l2 has risen suiliciently to permit the thermostat 30 to open its switch 35. v

During the cooling season when the deep well is serving as a dump for the heat that is extracted from the air by the refrigerating cycle, then the adjustments of the thermostat 30 are the reverse of those used in the heating season and are such that the thermostat-causes a discharge of well water to waste when a certain high temperature exists in the heat-conveying circulating system and cuts oil the discharge to waste when a certain lower temperature exists in the circulating system as will be understood. In such case the tendency of the operation of the heat pump would be to raise the temperature of the v The motor of pump 39 is controlled by an elec-' trical relay circuit actuated by thermostat 30, similar to the circuit that controls the waste valve 28 of the device of Fig. l.

In the form shown in Fig. 3 the waste pipe ll is directly connected to the water circulating system connecting the heat exchanger 42 to the deep well 9. The water thus wasted is replaced in this circulatory system by providing a low pressure relief valve 43 at some point in the loop I that is well below the ground water level ii. The waste valve 28 and its thermostatically con trolled electric circuit and solenoid, as shown, are the same as those of Fig. 1.

"The embodiments of the invention thatar shown in Figs. 1 and 2 are appropriate for use in climates where it is advantageous to use a circulating fluid in the closed conduit system that will a not freeze; whereas, the comparatively simpler form of Fig. 3 is suitable for use where temperature ranges are such that water from the well may serve as this circulating medium'.

Although several embodiments are herein shown and described. it will he understood that numerous details of the invention may be modi "lied or omitted without departing from the spirit We claim:

1. A heat pump, comprising a deep well communicating with a surrounding source of subterranean water, conduit means for recirculating a heat exchange medium in a closed circuit having a portion thereof submerged in said well, means for discharging standing water from said well, and thermostatic means actuated by temperature changes in said conduit to control said discharge means.

2. A heat pump, comprising a deep well communicating with a surrounding source of subterranean water, conduit means for recirculating a heat exchange medium in a closed circuit having a portion thereof submerged in said well, a system of piping and a pump for circulating the standing water of said well in heat exchange relation to said conduit means, a waste pipe connected to said system of piping for discharging standing water from said well, a valve controlling said waste pipe. and thermostatic means actuated by temperature changes in conduit to control said valve.

3. A heat pump, comprising refrigerant cycle apparatus including a heat exchanger, a deep well communicating with a surrounding source of subterranean water, closed conduit means adapted for continuously recirculating water in heat exchanging relation to both said heat exchanger and said well, means for discharging standing water from said well, and thermostatically controlled means actuated by temperature changes in said conduit to control said discharge means.

4. In a heat pump, comprising refrigerant cycle apparatus including a heat exchanger, a

deep well communicating with a surrounding source of subterranean water, and closed conduit means adapted for continuously recirculating water in heat exchanging relation to both said heat exchanger and said well, means for withdrawing standing water from said well, a discharge pipe communicating with the last named means, and thermostatically controlled means responsive to temperature changes in said conduit means arranged to control said discharge pipe.

5. In a heat pump, comprising refrigerant cycle apparatus including a heat exchanger, a deep well communicating with a surrounding source of subterranean water, and closed conduit means adapted for continuously recirculating water in heat. exchanging relation to both said heat exchanger and said well, means for withdrawing standing water from said well, thermostatic control means reponsive to temperature changes in said conduit means, and discharge means actuated by said thermostatic control means and arranged to govern the operation of said means for withdrawing water from said well.

'MARVIN M. SMITH.

EMORY N. KEMLER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name I Date 987,475 Martin Mar. 21, 1911 1,875,305 Hill Aug. 30, 1932 2,109,926 Nelson Mar. 1, 1938