US3695036A

US3695036A - Internal expansion vapor engine

Info

Publication number: US3695036A
Application number: US5253A
Authority: US
Inventors: James Earl Martin Sr
Original assignee: Individual
Current assignee: Individual
Priority date: 1970-01-23
Filing date: 1970-01-23
Publication date: 1972-10-03
Anticipated expiration: 1989-10-03

Abstract

The expansion of a low boiling point refrigerant is converted into useful work by supply of heat energy to the refrigerant internally of an expansible chamber type of prime mover. The heat energy is derived from an electrical source regulated by a power control which also governs circulation of the refrigerant through a refrigeration cycle and generation of heat to pressurize the refrigerant for injection into the working chamber of the prime mover.

Description

D United States Patent [151 3, 95,036

Martin, Sr. 1 Oct. 3, 1972 [54] INTERNAL EXPANSION VAPOR 3,294,079 12/1966 Thompson ..126/44 X ENGINE 3,531,933 10/1970 Baldwin ..60/36 [72] Inventor: James Earl Martin, Sr., 506 Wanda FOREIGN PATENTS QR APPLICATIONS St., San Angelo, Tex. 76901 235,061 6/1925 Great Bntam; ..60/27 Flledl J 3, 1970 310,450 l/ 1919 Germany ..60/27 21 A 1.N.:5253 1 pp Primary Examiner-Martin P. Schwadron Assistant Examiner-Allen M. Ostrager U-S. Attorney-Clarence OBrien and Harvey Jadob- [51] Int. Cl ..F0lk 25/10 Son [58] Field of Search ..60/27, 35, 36

[57] ABSTRACT [56] References Cited The expansion of a low boiling point refrigerant is UNITED STATES PATENTS converted into useful work by supply of heat energy to the refrigerant internally of an expansible chamber Dawson yp of mover. The heat gy is derived from 1,744,288 1/ 1930 Vorel ..60/27 an electrical Source regulated by a power comm] also governs circulation of the refrigerant 3,251,183 /1966 Whnlow ..60/27 through a refrigeration cycle and generation of heat to 3,479,817 /1969 M11110 ..60/36 pressurize the refrigerant f injection into the work 3,51 1,049 S/1970 Norton et a1. ..'.60/36 ing chamber of the prime mover 1,317,401 9/1919 Struever ..60/27 3,028,843 4/1962 Carlson et a1 ..122/17 19 Claims, 6 Drawing Figures Start 5% /02 "F & 640w 60- 32 P 9 56' 52 94 72 Burner 4 2a 54 l Vapar/zer A,- &

P 36 3e 70 M) e4 4 Butane [L Q fuel //0 t-- J 6 /22 l6 l2 Z4 Engine 26 1 E724 Evaparalar I20 Condenser I08 I06 I El Liquid Freon Receiver //4 PATENTEDBBTB 1m 3.695.036

SHEET 1 BF 2 Fig 12 62 46 o 5a Star! sm 6 Sw I 32 p ug 6O \x 1;: 94 72 56 52 V0 Burner reg. L 5 48/ 28 I e2 e4 Vap0r/zer30 A,- X\

68 74 I l 66 f /o4 Butane fuel I24 Evaporator I20 h I18 P L Condenser I08 Drier Liquid Freon I Receiver //4 James Earl Martin, Sr.

INVESTOR.

PATENTED BT 3 I912 SHEET 2 [IF 2 Fig. 5

James Earl Mart/n, Sr.

1 V E N TOR B gg glak system of the present INTERNAL EXPANSION VAPOR ENGINE This invention relates to a power plant utilizing a recirculating refrigerant as the working fluid in an expansible chamber type of engine.

An important object of the present invention is to provide a power plant generating useful energy with a minimum amount of air pollution and noise. The foregoing objective is realized by use of a non-combustible working fluid converted between liquid and vapor states in a thermodynamic cycle avoiding relatively heavy and bulky components commonly associated with such thermodynamic cycles such as a vapor generating boiler.

Although power plants which employ a working fluid undergoing a non-combustion, thermodynamic cycle, are well known, they involve a vapor generator or boiler by means of which the working fluid is vaporized externally of the engine and introduced under the desired vapor pressure into the expansible chamber of the engine in order to convert expansion of the working fluid into useful energy. Aside from the requirement of a substantial amount of fuel combustion in order to generate the heat necessary for the boiler, excessive losses often occur from condensation, radiation and boundary layer phenomena within the boiler. Further, such prior art power plant systems require a relatively complex control system in order to regulate the generation of power in accordance with varying demands and requirements.

In accordance with the present invention, the boiler or vapor generators usually associated with power plant systems of the aforementioned type is eliminated in favor of electrical heating elements located within the working chamber of the engine component to more efflciently develop the requisite vapor pressure for energy producing expansion. This is achieved by use of a relatively low boiling point refrigerant as the working fluid and a unique condensing-refrigeration system through which the refrigerant is controllably re-circulated and thermally processed or reconditioned for expansion within the working chamber of the engine. A power control assembly within a common control block regulates circulation of the refrigerant and operation of the refrigeration system as well as the generation of heat within the engine to cause expansion of the working fluid and supply of a relatively low volume of fuel to a burner for generating heat within a vaporizer by means of which the working fluid is preheated in order to develop a sufficient injection pressure necessary to introduce the working fluid into the working chamber of the engine. The engine may be either of the reciprocating piston type or the rotary vane type. In view of the relatively small quantity of fuel necessary to preheat the working fluid prior to introduction into the working chamber of the engine, and the type of fuel that may be utilized for this purpose, air polluting exhaust is substantially eliminated.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

FIG. l-is a schematic illustration of power plant invention, employing a reciprocating piston type of engine.

FIG. 2 is an end elevational view of a rotary vane type of engine that may be utilized with the power plant system of the present invention, in lieu of the reciprocating piston type of engine.

FIG. 3 is a longitudinal sectional view taken substantially through the plane indicated by section line 3-3 in FIG. 2.

FIG. 4 is a transverse sectional view taken substantially through a plane indicated by section line 4-4 in FIG. 3.

FIG. 5 is a side elevational view of the power control assembly associated with the power plant system.

FIG. 6 is a transverse sectional view taken substantially through a plane indicated by section line 6-6 of FIG. 5.

Referring now to the drawings in detail, FIG. 1 illustrates the power plant system generally denoted by reference numeral 10 through which energy derived from a source of liquid fuel 12 is converted into useful mechanical energy at the output shaft 14 of a prime mover generally referred to by reference numeral 16. In FIG. I, the prime mover 16 is of the reciprocating piston type having a cylinder housing 18 enclosing an expansible work chamber 20 on one side of a reciprocating piston 22 connected by the pitman 24 and crank 26 to the output shaft 14.

The liquid fuel from the source 12 is butane which produces a low polluting exhaust as a result of combustion within a Bunsen type burner assembly 28 forming part of a vaporizer component 30 which includes a heat exchanger 32 within which heat generated by the burner 28 is transferred to a working fluid in the form of a low boiling point refrigerant. Refrigerants selected for the purposes of the present invention are included in a class of fluids known as Freon which is a poor conductor of electricity and in its vapor state does not contaminate available lubricants. Refrigerants found most suitable for the present invention from the latter group consist of Freon-502 having a boiling point temperature of 50 F. and Freon-13 having a boiling point temperature of l l4.60 F.

The refrigerant is preheated within the vaporizer component 30 through which it is conducted in order to sufficiently pressurize it to an injection pressure enabling the refrigerant to be introduced into the expansible chamber 20 of the engine through a one-way injection valve 34. Accordingly, during the intake stroke of the piston 22, the refrigerant under the proper injection pressure will charge the expanding chamber 20. During the compression stroke of the piston, while the chamber 20 is contracting, the injection valve 34 will close. Supply of heat to the refrigerant while trapped within the working chamber 20, will at the proper point in the cycle of the engine, cause volumetric expansion and produce the power stroke for the piston.

In order to generate heat internally within the working chamber of the engine 16, the housing mounts heating elements 36 in the head portion 38 and heating elements 40 on the piston as diagrammatically shown in FIG. 1. These heating elements may be of the disc type. The heating elements 40 may be electrically connected in parallel with the heating elements 36 during the proper phase in the engine cycle through switch means 42 to a source of electrical energy which includes a battery 44 adapted to be charged by a generator 46 under the control of a voltage regulator 48. The heating elements 36 and 40 are accordingly connected across the positive and

negative terminals

50 and 52 of the power supply formed by the battery and generator, in series with a rheostat 54 including an adjustable resistance 56 and movable contact 58. The electrical system also in cludes a glow plug 60 associated with the burner assembly 28 of the vaporizer component. Upon closing of a start switch 62 for the power plant, electrical energy is conducted through the glow plug 60 in order to ignite the fuel supplied to the burner from the fuel source 12.

The fuel is supplied under pressure to the burner from a conventional, portable tank by a fuel pump 64 driven by an electric motor 66 connected to the electrical source of energy. The fuel supply conduit 68 extending from the fuel pump is connected to a one-way by-pass valve 70 arranged to return the fuel to the tank when the output pressure reaches an excessive value such as psi. The pressurized fuel is supplied to the burner from the conduit 68 through a fuel supply valve device 72 when opened.

The fuel supply valve device 72 forms part of a power control assembly 74 which also includes a refrigeration control valve device 76 and an evaporator control valve device 78 adapted to be opened simultaneously with the fuel valve device 72. The inlet ports to the

valve devices

76 and 78 are connected to a liquid refrigerant supply conduit 80 forming part of a refrigeration system through which the refrigerant is circulated. As shown in FIGS. 1, 5 and 6, the power control assembly 74 includes a movable control member such as an accelerator pedal 82 connected to

valve actuator elements

86, 88 and 90 associated with the

valve devices

72, 78 and 76. The valve devices are mounted within a common valve block 92. The valve device 72 controls a separate passage between the fuel supply conduit 68 and an outlet conduit 94 connected to the burner 28. The inlets of both of the

valves

76 and 78 are connected to a manifold passage 96 to which the liquid refrigerant supply conduit 80 is connected. Thus, upon opening of the

valve devices

76 and 78, liquid refrigerant is supplied to

outlet conduits

98 and 100. When the pressure of the liquid refrigerant within manifold passage 96 exceeds a certain pressure, a spring-biased by-pass valve 102 opens for return of liquid refrigerant from the supply conduit 80 through a by-pass conduit 104 to a liquid refrigerant receiver tank 106 as shown in FIG. 1.

At the same time that the three

valve devices

72, 76 and 78 are displaced in an opening direction through actuating rod 84, the contact arm 58 of the rheostat device 54 is displaced in a direction reducing the resistance in series with the heating elements to thereby increase the heat energy transferred to the refrigerant within the working chamber of the engine. Although the actuating rod 84 is diagrammatically shown in FIG. 1 as connected to an accelerator pedal 82, it should be appreciated that it may be jointly controlled by other means in order to regulate operation of the power plant system. For example, there may be a temperature control to automatically compensate for changes in ambient temperature when the amount of refrigeration necessary for efficient operation would change.

The refrigeration system includes a condenser component 108 as diagrammatically shown in FIG. 1 having an inlet to which exhaust conduit 110 is connected for conducting refrigerant in a gaseous state from the engine after it has completed the expansion phase. The heating remaining in the refrigerant when exhausted from the engine, is removed by the cooling effect of ambient air passing through the coils of the condenser under the inducement of a fan 1 l2 driven by the output shaft 14 of the engine. The refrigerant after being cooled within the condenser 108 is conducted therefrom by the outlet conduit 114 through a dryer 116 and returned to the liquid refrigerant receiver 106 from which the liquid refrigerant is recirculated by a pump 118 also driven by suitable gearing from the output shaft 14 of the engine which also drives the generator 46. The mechanical energy imparted to the refrigeration system by the pump 118 is merely sufficient to maintain circulation of the refrigerant by inducing flow of the refrigerant in a liquid state through the refrigerant supply conduit to the vaporizer component 30 within which the refrigerant is preheated for the purpose of developing the requisite injection pressure as aforementioned.

Removal of heat from the refrigerant while it passes through the condenser 108 is furthermore enhanced by heat exchange with an evaporator component 120 through which liquid refrigerant is recirculated from the outlet conduits 98 and of

valve devices

76 and 78. The cooling effect of the evaporator component on the condenser 108 with which it is in heat conductive relation, is effected through an expansion valve 122 interconnected between conduit 98 and the evaporator as shown in FIG. 1. Thus, the liquid refrigerant undergoes volumetric expansion through the valve 122 before being conducted through the evaporator within which it absorbs heat from the condenser. The expansion valve 122 is of a commercially available type having an adjustable orifice which is automatically variable under control of a sensor 124 mounted on the condenser and connected to the expansion valve by the capillary tube 126. Thus, the expansion valve 122 may be preset in accordance with the volume of refrigerant conducted through the evaporator for all types of operation in order to accommodate condensation of vapor for a desired temperature, as low as 40 F. for example. The evaporator may be in the form of four layers of 15-inch inside diameter tubing mounted directly on the condenser.

Referring now to FIGS. 2, 3 and 4, a rotary vane type of engine 128 is shown which may replace the reciprocating piston type of engine 16 illustrated in FIG. 1. The engine 128 includes an elongated cylindrical housing 130 closed at opposite axial ends of end walls 132 with which the housing 130 is held assembled by means of a plurality of fasteners 134. Glands 135 seal the ends of the housing enclosing a working chamber 136 into which the vaporized refrigerant is injected through the injection valve 34. The housing also encloses a rotor 138 supported by a shaft 140 in eccentric relation to the cylindrical chamber 136. Glands 141 are mounted by the end walls to seal the chamber about the shaft 140 which is supported by bearing assemblies 142 on opposite axial sides of the housing.

The rotor 138 slidably mounts three reciprocable vanes 144 adapted to be radially extended from the rotor for wiping contact with the walls of the chamber 136 under the influence of centrifugal force. The power side of the vanes may be lubricated by periodically injected lubricant which is collected by lubricant collecting wipers 146 as shown in FIG. 4. Also, electrical heating elements 148 of the strip type are externally mounted on the rotor between the vanes in order to perform the functions performed by the disc type heating elements 36 and 40 described in connection with the engine 16. The heating elements 148 are electrically connected to conductive discs 150 secured to the axial ends of the rotor and non-conductively spaced by spacers 152 from the shaft mounted assembly discs 154 v as shown in FIG. 3. Conductive brush elements 156 are spring-biased into wiping engagement with the conductive discs 150 so as to establish electrical connections through the threaded terminals 158 to the source of electrical energy such as that described in connection with FIG. 1. Accordingly, the refrigerant introduced into the working chamber 136 will be heated internally of the engine 128 causing expansion against the vanes 144 to produce rotation of the rotor and then exhausted through the exhaust conduit 1 10.

Operation of the power plant system is initiated by closing of the start switch 62 to ignite the burner 28 through the glow plug 60. When the accelerator pedal 82 is then depressed, the valve device 72 opens so that the butane burner 28 may generate an increasing amount of heat dependent on the opening of the valve 72 for pressurizing the refrigerant to increase the amount of refrigerant injected. At the same time, the resistance of rheostat 54 is reduced to increase the heating effect of the heating elements causing expansion of the refrigerant within the working chamber of the engine, the refrigerant being supplied from the receiver 106 through the pump 118 at all times. Also, while the engine is being accelerated by depression of the accelerator pedal 82, the

valve devices

76 and 78 open in order to render the refrigeration system operative and thereby effectively remove heat from the refrigerant exhausted from the engine by the cooling effect of the evaporator 120 on the refrigerant conducted through the condenser 108.

The vaporizer component 30 causes the refrigerant to change from a liquid to the gaseous state prior to injection into the engine in order to maintain a proper injection pressure during the acceleration mode of operation. Vaporized refrigerant is injected during the nonpower, intake phase of engine operation since during the other phases of operation, the working chai'nber at a high pressure will be sealed by the injection valve 34. Pressurization and expansion of the refrigerant within the working chamber rapidly occurs as a result of the heat supplied thereto from the electrical source. The heat generated by the heating elements maintains operation of the engine during the idling mode of operation when there is a minimum pressurization of the refrigerant by the vaporizer component 30. Thus, the power plant is maintained in a standby condition for acceleration. Should the electrical system fail, the power plant would continue to operate by opening of all the valves in the control assembly 74, heat then being supplied to the refrigerant solely by the vaporizer component 30 which ordinarily merely maintains a proper injection pressure under engine accelerating conditions. At high speeds of the engine, release of the accelerator pedal 82 would produce a high braking effect by cutting off circulation of the refrigerant through the refrigerating cycle.

The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly all suitable modifications and equivalents may be resorted to falling within the scope of the invention as claimed.

What is claimed as new is as follows:

1. A power generating system comprising an expansible chamber device having a working chamber, means for injecting a refrigerant into the working chamber, means connected to the injecting means for preheating the refrigerant to vaporize and pressurize the same prior to introduction into the working chamber, said vaporized refrigerant being introduced into the working chamber at a pressure insufficient to produce expansion of the working chamber, means for heating the vaporized refrigerant internally of the working chamber causing volumetric expansion thereof, means connected to the expansible chamber device for removing heat from the refrigerant exhausted from the working chamber following said expansion thereof, and recirculating means for inducing flow of the refrigerant to the preheating means from the heat removing means.

2. The combination of claim 1 wherein said refrigerant is liquified in the recirculating means.

3. The combination of claim 2 wherein said heat removing means includes a condenser coil assembly through which the refrigerant is conducted, blower means driven by the expansible chamber device for cooling the condenser coil assembly and evaporator means mounted in heat conductive relation to the condenser coil assembly for absorbing heat therefrom in response to flow of the refrigerant therethrough.

4. The combination of claim 3 including power control means connected to the heating means and the recirculating means for simultaneously varying the heating of the refrigerant internally of the working chamber and cooling of the refrigerant by the heat removing means.

5. The combination of claim 4 wherein said pre-heating means includes a source of fuel under pressure, a burner connected to said source of fuel, and heat exchange means through which the refrigerant is conducted for absorbing heat generated by the burner.

6. The combination of claim 5 wherein said heating means includes a source of electrical energy, electrical heating elements mounted by the expansible chamber device within the working chamber and adjustable resistance means connecting the source of electrical energy to the heating elements.

7. The combination of claim 6 wherein the power control means includes a first valve device connecting the recirculating means to the evaporator means, a second valve device connecting said source of fuel to the burner, and actuator means connected to said valve devices and the adjustable resistance means for simultaneously opening the valve devices and decreasing the resistance of the adjustable resistance means to accelerate the expansible chamber device.

8. The combination of claim 7 wherein said recirculating means includes a refrigerant receiver connected to the heat removing means, pump means driven by the expansible chamber device and connected to the receiver for inducing flow of the refrigerant in a liquid state from the receiver and conduit means connecting the pump means to the preheating means and the power control means for supply of liquid refrigerant to the heat exchange means and the evaporator means.

9. The combination of claim 1 wherein said heat removing means includes a condenser coil assembly through which the refrigerant is conducted, blower means driven by the expansible chamber device for cooling the condenser coil assembly and evaporator means mounted in heat conductive relation to the conde'nser coil assembly for absorbing heat therefrom in response to flow of the refrigerant therethrough.

The combination of claim 9 wherein said preheating means includes a source of fuel under pressure, a burner connected to said source of fuel, and heat exchange means through which the refrigerant is conducted for absorbing heat generated by the burner.

11. The combination of claim 10 wherein said recirculating means includes a refrigerant receiver connected to the heat removing means, pump means driven by the expansible chamber device and connected to the receiver for inducing flow of the refrigerant in a liquid state from the receiver and conduit means connecting the pump means to the preheating means for supply of liquid refrigerant to the heat exchange means.

12. The combination of claim 1 including power control means connected to the heating means and the recirculating means for simultaneously varying the heating of the refrigerant internally of the working chamber and cooling of the refrigerant by the heat removing means.

13. The combination of claim 12 wherein said heat removing means includes a condenser coil assembly through which the refrigerant is conducted, blower means driven by the expansible chamber device for cooling the condenser coil assembly and evaporator means mounted in heat conductive relation to the condenser coil assembly for absorbing heat therefrom in response to flow of the refrigerant therethrough.

14. The combination of claim 13 wherein said heating means includes a source of electrical energy, electrical heating elements mounted by the expansible chamber device within the working chamber and adjustable resistance means connecting the source of electrical energy to the heating elements.

15. The combination of claim 14 wherein the power control means includes a first valve device connecting the recirculating means to the evaporator means, a second valve device connecting said source of fuel to the burner, and actuator means connected to said valve devices and the adjustable resistance means for simultaneously opening the valve devices and decreasing the resistance of the adjustable resistance means to accelerate the expansible chamber device.

16. The combination of claim 1 wherein said heating means includes a source of electrical energy, electrical heating elements mounted by the expansible chamber device within the working chamber and adjustable resistance means connecting the source of electrical en r to the heatin elements.

i7 f The combina ion of claim 16 including power control means connected to the heating means and the recirculating means for simultaneously varying the heating of the refrigerant internally of the working chamber and cooling of the refrigerant by the heat removing means.

18. The combination of claim 16 wherein said expansible chamber device is of the reciprocating type having a housing enclosing the working chamber and a piston reciprocating therein, said heating elements being mounted on the housing internally of the working chamber and the piston.

19. The combination of claim 16 wherein said expansible chamber device is of the rotary vane type having a housing enclosing the working chamber, a rotor rotatably mounted within the housing and three radially reciprocating vanes, movably mounted by the rotor, heating elements being mounted on the rotor between the vanes.

Claims

9. The combination of claim 1 wherein said heat removing means includes a condenser coil assembly through which the refrigerant is conducted, blower means driven by the expansible chamber device for cooling the condenser coil assembly and evaporator means mounted in heat conductive relation to the condenser coil assembly for absorbing heat therefrom in response to flow of the refrigerant therethrough.

10. The combination of claim 9 wherein said pre-heating means includes a source of fuel under pressure, a burner connected to said source of fuel, and heat exchange means through which the refrigerant is conducted for absorbing heat generated by the burner.

16. The combination of claim 1 wherein said heating means includes a source of electrical energy, electrical heating elements mounted by the expansible chamber device within the working chamber and adjustable resistance means connecting the source of electrical energy to the heating elements.

17. The combination of claim 16 including power control means connected to the heating means and the recirculating means for simultaneously varying the heating of the refrigerant internally of the working chamber and cooling of the refrigerant by the heat removing means.