United States Patent 3803847

An energy conversion system, particularly for use in heating, cooling, and generating electrical and mechanical power for an area such as a dwelling. In one embodiment, vapor is alternately directed into one of two reservoir tanks so that working fluid in that tank is forced out of that tank by the vapor pressure and through a hydraulic motor, which powers a compressor and/or other devices such as an electrical power generator, garbage disposal, etc., before it returns to refill the other tank. The system includes a closed loop circuit involving a heat pump compressor for circulating fluid to heat and cool air within a building or the like. When the loop is set in a cooling configuration, compressed fluid passes through a first heat exchanger rejecting heat, and then through an expansion valve to a second heat exchanger, cooling the air about that exchanger before returning to the compressor. When the loop is set in a heating configuration, the compressed fluid in its gaseous state passes first through the second heat exchanger, where it transmits heat to the surrounding air, through the expansion valve and then through the first exchanger, where it receives heat not converted into shaft work by the hydraulic motor before returning to the compressor.

Application Number:
Publication Date:
Filing Date:
Primary Class:
Other Classes:
62/324.3, 62/467, 91/4R
International Classes:
F01K27/00; (IPC1-7): F01K27/00
Field of Search:
62/324,467 60
View Patent Images:
US Patent References:
3608311N/A1971-09-28Roesel, Jr.
3304735Automotive heat pump1967-02-21Alexander
3275067Reversible heat pump system1966-09-27Sniader
3100965Hydraulic power supply1963-08-20Blackburn
2562748Heat pump1951-07-31Smith et al.

Primary Examiner:
Geoghegan, Edgar W.
Assistant Examiner:
Ostrager, Allen M.
Attorney, Agent or Firm:
Cushman, Darby & Cushman
What is claimed is

1. An energy conversion system comprising a heat engine and a heat pump circuit, said heat engine including



The invention relates to an energy conversion system for heating and cooling an area, such as the interior of a building.

Most heating and cooling systems now in use include one device which burns fuel or resistively heat wire for providing heat in the winter and another device for cooling in the summer. Although the two devices frequently share the same air handling duct work, such devices are generally inefficient and less than completely satisfactory in many instances. In the summer, for instance, an electric motor driven heat pump provides cooling, but in the winter the heat pump often is not able to absorb sufficient heat at the evaporator due to icing and subsequent inefficiencies.

The present invention relates to a heating and cooling system wherein a hydraulic motor is employed within a fluid configuration for cooling. The hydraulic motor is operated by an energy conversion system of the type wherein high pressure vapor is alternately directed into one of two reservoir tanks so that working fluid in that tank is forced out of that tank by the vapor pressure and through the hydraulic motor.

In the embodiment described below, the hydraulic motor is mechanically linked to a conventional compressor which is connected in the loop in both the heating and cooling configurations, together with a conventional expansion valve and two heat exchangers, which serve respectively as a condensor and evaporator. In the heating configuration, the compressed temperature control fluid in its gaseous state first passes through one heat exchanger which is disposed so that it exchanges heat with the surrounding air, which is then circulated throughout the building or the like. After the high pressure gaseous fluid transfers heat to the surrounding air, it passes through a conventional expansion valve which reduces the pressure to a relatively low value and accordingly lowers the temperature. The expanded fluid next passes through a second heat exchanger from which it absorbs heat. The selection of the temperature control fluid and its resulting physical properties may require the first heat exchanger to be designed as a condensor and the second as an evaporator because a significant portion of the fluid may be converted to the liquid state in the first heat exchanger.

In the cooling configuration, the compressed temperature control fluid in its gaseous state first passes through the second heat exchanger where, because of the high pressure resulting from compression, it cools while being maintained at the compressor pressure by transferring heat, preferably to water flowing through the exchanger so that the heated water can be used for washing clothes, drying clothes, bathing, cooking, etc. The compressed, but cooled liquid then passes through the thermally isolated expansion valve, which again reduces the pressure to a lower value and thereafter the fluid is circuited through the first heat exchanger, which in this configuration may be required to serve as an evaporator or expander absorbing heat from the surrounding air. In this configuration, the first heat exchanger serves as an expander or evaporator and the second heat exchanger as a constant pressure heat rejector or condensor.

Further, the mechanical output of the hydraulic motor can also be connected to an electrical generator for providing electrical power and/or other devices for performing other useful functions such as driving garbage disposals, washers, dryers, water pumps, air circulation fans, etc. Thus, the novel system of this invention is a particularly simple and effective system for not only heating and cooling an area such as a building employing only a single simple basic energy conversion device for doing so, but also for performing many other functions presently accomplished by other devices. Any fuel can be burned to derive heat to operate the energy conversion system and accordingly the system is very flexible.

Many other objects and purposes of the invention will become clear from the following detailed description of the drawings.


FIG. 1 shows the novel heating and cooling system of this invention in its cooling configuration.

FIG. 2 shows the novel heating and cooling system of this invention in its heating configuration.


Reference is now made to FIG. 1 which shows one embodiment of this invention in the cooling configuration. As mentioned above, the system includes an energy conversion device 18 of the type wherein fluid is alternately forced from one reservoir tank through at least one fluid motor or hydraulic cylinder into the other tank. Such devices are described in further detail in a McAlister application, Ser. No. 58,981 filed July 28, 1970, now U.S. Pat. No. 3,756,086, and entitled VAPOR PRESSURIZED HYDROSTATIC DRIVE, the disclosure of which is explicitly incorporated herein by reference. The system is particularly suitable for use with one or more hydrostatic motors in parallel with each other or in series. In this embodiment, as in many of the other embodiments of the invention as set forth in the above mentioned McAlister application, vapor is alternately directed into one of the two reservoir tanks 20 and 22 so that the working fluid in the tank is forced out of the tank by the pressure of the vapor, and through a conventional hydraulic motor 38 to generate a mechanical output before it returns to refill the other tank. When the first tank is substantially depleted, the vapor pressure is directed into the refilled tank so that the fluid from the tank now flows again through motor 38 to refill the first, now depleted, tank.

In FIG. 1, a suitable reservoir 24 or a fluid such as water is connected to a conventional phase converter or boiler 26, which converts the fluid from a liquid to a vapor phase. This conversion may be accomplished by burning a suitable fuel such as the hydrocarbons, so that the generated heat changes the phase of at least a portion of the fluid in boiler 26. Any other suitable arrangements for generating the vapor which is employed to impart motion to the working fluid can be employed. The vapor pressure output of boiler 26 is directed to either reservoir tank 20 or tank 22 via master valve 28, which may be a conventional solenoid valve or any othe suitable type of valve mechanism. As depicted schematically in FIG. 1, valve 28 is operated by a suitable control apparatus 30, which alternately causes valve 28 to direct the vapor pressure generated by boiler 26 into one of the reservoir tanks 20 and 22. Control 30 may be mechanically or otherwise linked to the fluid motor 38, so that the position of the valve 28 is responsive to the physical position of the rotating part of fluid motor 38. Alternately, control 30 may include means for sensing the fluid level by electrical or thermal information in tanks 20 and 22 and switching the vapor flow from tank to tank whenever the fluid in either tank is detected above or below a certain predetermined level.

Assume for purposes of describing the operating of the embodiments of FIG. 1 and 2, that control 30 has shifted valve 28 to a position such that the vapor pressure generated by boiler 26 is transmitted into tank 22 as depicted, causing the fluid in tank 22 to exit from the bottom of tank 22 and to flow theough motor 38 via one way check valve 32 as well as the other check valves in this and the other embodiments set forth below, permit fluid flow in one direction but prevent it in the other. Those valves may be of any suitable type and are well known in the art. After passage through motor 38, the moving fluid passes through check valve 34 and enters tank 20. An exhaust vlave 40, which also is shown under the control of apparatus 30, is preferentially vented to heat exchanger 50 when the dwelling is being heated and vented to the atmosphere during times when the dwelling is being cooled, so that thefluid can freely enter tank 20. Valve 42, at the same time, is closed to prevent the loss of the vapor pressure generated by the flow of vapor into tank 22 via valve 28.

The cyclic venting of tanks 20 and 22 to heat exchanger 50 in the heating configuration and to the atmosphere in the cooling configuration may in some duty cycles result in a gradual reduction in the quantity of working fluid in the sustem. Reservoir 24, provides some make-up fluid since some of the vapor directed into the tanks condenses therein and is thus added to the supply of working fluid. However, it may be desirable to provide some suitable arrangement for automatically or otherwise replenishing the working fluid from time to time.

When tank 22 has been depleted or substantially depleted, control mechanism 30 shifts the position of valve 28 so that the vapor pressure generated by boiler 26 is now directed into tank 20 and begins to force the fluid which has refilled it out of tank 20 and through fluid motor 38 via check valve 36. At the same time, exhaust valve 40 is closed and valve 42 opened by apparatus 30, so that the fluid now flowing through motor 38 bia check valve 36 returns to tank 32 via check valve 39. Open valve 42 permits the vapor pressure in chamber 22 to escape to the atmosphere, so that tank 22 can refill.

A portion of the fluid flowing out of one or the other of the tanks 20 or 22 also returns to reservoir 24 via valve 32 or 36. Fluid entering the boiler from reservoir 24 may be manually or otherwise adjusted by apparatus 20 to provide a suitable flow of liquid for vaporization within boiler 26. As mentioned above, while water is one suitable material which exits in the vapor and gaseous phase and can be suitably used in this arrangement, any other suitable fluid which can be satisfactorily converted from its liquid to its vapor phase can be employed. The use of a common fluid in the air conditioning loop and the boiler loop with heat exchange to the air from closed heat exchangers would be recommended in situations where gound water was of low quality or unavailable.

Hydraulic motor 38 is mechanically lined to a conventional compressor 52, which causes both compression of the temperature control fluid and circulation of the temperature control fluid about a closed loop in both the heating and cooling configurations. Motor 38 or another hydraulic motor in series or parallel may also be connected to a conventional electrical generator 54 for providing electrical power for the building. Other hydraulic motors and hydraulic cylinders may be employed to other devices 56 such as fans, garbage disposals, dish washers, clothes washers, clothes dryers, and trash compactors. Devices 56 can include any apparatus capable of being operated from the mechanical output of motor 38 or from a hydraulic cylinder.

When system 18 is to be operated in the cooling configuration, valves 60, 62, 64, and 66 are shifted manually or automatically to their open positions as shown in FIG. 1 and valves 68, 70, 72, and 74 to their closed positions. When the valves are in the positions shown in FIG. 1, the temperature control fluid compressed by compressor 52, flows through line 80, valve 60, line 82, and heat exchanger 50 in the direction indicated by the arrows. Further, when in the cooling configuration, valves 84 and 86 are closed and valve 91 open so that ground water at a relatively low temperature T1 flows into heat exchanger 50. It is further preferred while in cooling operation to open valves 118 and 119 allowing fluid returning from the motors or hydraulic cylinders, which has been cooled by passing from a high pressure state to a low pressure state by doing work in the motor and further by dissipating heat to the surroundings to enter the reservoirs 20 and 22 in a means accomplishing condensation of residual vapors so that the pressure in a reservoir during filling approaches the working fluid's vapor pressure at the temperature of the return fluid. Thus, the reservoirs' filling pressure generally is below the pressure of chamber 50, and enables the evaporating fluid exiting chamber 50 at T2 to be added to reservoirs 20 and 22 through valves 40 and 42, or through separate circuits, with the result of a depressed temperature (T2) due to increased evaporative cooling at the reservoir filling pressure.

When the system to operate in the heating configuration, valves 60, 62, 64, and 66 are shifted to their closed positions and valves 68, 70, 72, and 74 to their open positions as shown in FIG. 2. Accordingly, the compressed temperature control fluid in its gaseous state first passes through heat exchanger 102 via valve 68. Because of the relatively high pressure produced by compressor 52, heat is transferred to the air about exchanger 102 in the process. The air thus heated is then conventionally circulated. The fluid via valves 70 and 96 and then enters exchanger 50 via vlave 72. Water at a temperature T1, which may be considerably higher than outside air because of heat gained from exchanger 109 consisting of heat not converted into mechanical power by the energy conversion engine system, enters the heat exchanger 50, transfers heat to the expanded temperature control fluid and exits at a temperature T2 as shown, which is less than T1. Thus, heat not used in powering convenience devices is used to heat the home.

Further, when the system is in the cooling configuration, FIG. 1, tanks 20 and 22 are preferably vented to heat exchanger 50 as shown. This allows the tank being filled to be at a partial pressure equal to the water vapor pressure. By placing the line between tanks 20 and 22 and exchanger 50 in a position causing Bernoulli pumping while the tank is filling, exchanger 50 may be evacuated allowing the development of a lower temperature in the heat exchanger than the entering ground water temperature T1.

Many changes and modifications in the above embodiments of the invention can of course, be made without departing from the scope of the invention which is intended to be limited only by the scope of the appended claims.