rexresearch.com
John ROESEL
Liquid Piston Engine
Liquid Piston Engine
https://books.google.com/books?id=bAEAAAAAMBAJ
Popular Science ( October 1974 )
[ Related : Fluidyne Pump -- Popular Science ( January 1975, Page 71 ) ]
ENGINE
US3608311 / CA920374 / GB1335419
Inventor: ROESEL JOHN F JR US3608311 / CA920374 / GB1335419
1971-09-28
ABSTRACT OF THE DISCLOSURE
In a heat engine where heat is applied to a working fluid contained in a chamber to expand the fluid, removing the heat source while allowing the fluid to expand further, applying cooling while compressing the working fluid and removing the cooling while further compressing the fluid, said fluid during said expansion being applied to utilization means to perform work, the improvement therein comprising: having at least two chambers which contain a liquid and a gas section; hot and cold lines connecting 20 the liquid sections to the gas sections, including pumping means, heating and cooling means in the respective lines; forward and return flow passages communicating; between said liquid sections across one-way valves which allow flow into the forward flow passage and out of the return 25 flow passage, and a work area in series between the forward and return passages; and, timer means coupled to said hot and cold lines to sequentially allow hot and cool liquid to flow from liquid to gas sections to cause gas expansion and compression resulting in a flow of liquid out 30 of at least one chamber into said forward passage and/or out of said return passage into at least one chamber across said work area.
BACKGROUND OF THE INVENTION
The present invention relates to a differential heat engine and more particularly to a closed cycle heat engine which has controllable rate and duration of the heat input and rejection processes with few moving parts.
BRIEF DESCRIPTION OF THE PRIOR ART
The fundamental concept of a heat engine is based upon the so-called "Carnot cycle" named after Nicolas Leonard Sadi Carnot. Carnot's work in the early nineteenth century was continued by Diesel and indeed, Diesel's early versions of his now famous diesel engine was based upon the teachings of Sadi Carnot. It is significant that heretofore, although "Carnot cycle" engines were known, they exist only in textbooks and as scientific 50 curiosities (C. Osborn Mackey et al., Engineering Thermodynamics, John Wiley & Sons, page 255) without any application in practice as industrial machines. The present invention concerns an industrial machine based on the teachings of Sadi Carnot and avoiding the pitfalls which befell Diesel, Stirling and others.
A heat engine converts heat into work by adding heat to a working fluid, usually a gas, so that the fluid expands and exerts pressure on a piston or on turbine blades. Although steam and air are the most common working 60 fluids, in theory any gas can serve as the medium for this kind of energy conversion. The efficiency of the process, according to Carnot, does not depend on the choice of medium, but obviously some gases have more convenient properties than others. 65 The usual Carnot cycle engine described in textbooks is a one-cycle engine with a piston. In an ideal Carnot 2 cycle engine, at the start of the cycle, a large heat reservoir is in contact with the cylinder head, and beat flow ing from it into the working fluid causes the fluid to expand isothermally, that is, without an increase in temperature. Next, the heat source is removed and the cylinder head is insulated, the working fluid continues to expand 14 Claims with the expansion being adiabatic, that is, without the flow of heat to or from the fluid. The temperature of the fluid therefore drops. Then the piston must be driven back, compressing the fluid before it. During this compression the cylinder head is placed in contact with a cooler heat reservoir so that as the compression process occurs, heat flows from the fluid to the cold body such that the temperature of the fluid remains constant and the compression is isothermal. Finally, the cold body is re placed by insulation and the piston is returned to the starting position by adiabatic compression. The energy generated by the piston's work raises the temperature of the working fluid to its original level, thereby completing the cycle.
It is significant that the previous workers in the field, e.g., Brayton, Otto, Diesel, were not able to successfully construct a practical engine which operated on the Carnot cycle even though serious attempts were made to do so.
In particular, the requirement of isothermal expansion has not been possible to meet in engines where air is the working fluid and its oxygen is used for combustion within the cylinder. Also, when combustion occurs in the cylinder, the combustion products must be removed and fresh air brought in. Therefore, in an internal combustion engine, the system must be an open one.
Attempts have been made by other workers in the field to eliminate the troublesome piston. Typical of these at tempts is the one described in the T. Y. Korsgren, Sr., U.S. Pat. No. 3,183,662. However, in this patent, mechanically coupled fluid displacers are used which limit the cycle to that defined by Stirling. Also, the working cycle of the engine is closely coupled to the hot and cold cycle which hinders the usefulness of the engine in practice.
The present invention, on the contrary, relates to a Carnot cycle closed loop system. It uses a heat transfer process which has a controllable duration and heat transfer rate in and out of the expansion chamber. This allows the tailoring of the cycle to meet isothermal or other requirements.
Furthermore, although the components shown and de scribed herein appear in a compact configuration, the various component sections can be separated, elongated, and extended so as to occupy almost any type of space provided.
This makes the engine particularly suitable for use where packaging is important, e.g., as a boat or airplane engine.
SUMMARY OF THE INVENTION
Generally speaking, the present invention provides for an engine preferably having at least two insulated chambers. Although these are shown one alongside the other in the drawing, they can be widely separated. Each chamber contains a gas and a liquid. The expansion and contraction of the gas in these chambers force the liquid to pass in and out through one-way valves connected to exit and return lines. These valves may be simple passive spring loaded check valves, or in some cases, they may be positive acting externally controlled valves. On expansion, fluid passes out of one chamber through a work flow chamber, which extracts work from the fluid and passes into the second chamber causing compression of its gas. Some of the liquid is also pumped separately from the liquid sections through two lines, one which is heated and the other cooled. During this heating and cooling, a phase change may or may not occur, e.g., it may form a gas upon heating. Heat is transferred to or from the gas at will by sequentially pumping hot or cold fluid to the gas section of the chamber. The amount, duration and 10 timing of the heat transfer is controlled by a distributor timer connected to the hot and cold lines. The fluid pumped into the gas section flows down to the liquid section to close its cycle.
It is also possible to operate with only one chamber and 1,5 a reservoir, instead of the second chamber.
The invention, as well as the objects and advantages thereof will be more apparent from the following detailed description, when taken in connection with the accompanying drawing in which:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. I is a cross-sectional flow diagram of a simplified form of the engine contemplated herein;
FIG. 4a is a cross-sectional flow diagram showing a 25 modified version of the arrangement depicted in FIG. 1;
FIG. lb also presents a cross-sectional flow diagram with another modification of the version shown in FIG. 1;
FIG. 2 shows a cross-sectional view of an industrial version of the engine contemplated herein;
FIG. 3 is a cross-sectional view along lines 3-3 of FIG. 2; and, FIG. 4 shows a modified version of the arrangement shown in FIG. 3.
DETAILED DESCRIPTION
Shown in FIG. I is a differential heat engine 10, having a first insulated expansion chamber 12 and a second insulated expansion chamber 14. Each chamber is outwardly in the form of an elongated narrow rectangle and is divided generally into a gas section 16, 16a and a liquid section 18, 18a. Advantageously, a layer of solid insulation 19 can be disposed to float over the liquid between the two sections. Connected to the output side or bottom of each chamber is a Y-connection 22 leading to a work flow chamber 24, wherein is located an output motor. a From the work flow chamber 24 are first and second return lines 26, 28 to the first and second oil expansion chambers 12, 14. Each arm of the Y- connection 22 has an out-going check valve 30, 32. Each return line 26, 28 likewise has an in-feeding check valve 34, 36, i.e., 50 these are inflow valves. Each expansion chamber has a hot injection line 40, 40a and a cold injection line 42, 42a going from the liquid section to the gas section in each chamber. These lines respectively pass through heating means 44, 44a and cooling means 46, 46a. There is 55 also a pump 48a, 48b, 48c, 48d in each line. Each line is connected to a timer 52, which can alternately act on a hot injection line and a cold injection line in each chamber.
SIMPLE OPERATING SEQUENCE
The engine operates as follows:
The hot line for one chamber and the cold line for the other chamber are acted on by the distributor timer. Liquid is pumped by the respective pumps and ejected 65 out of nozzles from the hot and cold lines. As the hot liquid is injected into the chamber by the nozzle, it is broken up into many fine particles which together present a large surface area to the gas. The gas expands pressing down on the liquid. Other means of creating small droplets 70 may also be used. The liquid flows through the one-way valve into one leg of the Y-connection into the work flow chamber. The work flow chamber has a turbine arrangement with an output shaft. As the liquid flows through the chamber, it causes the shaft to turn. The liquid then 4 goes into the return paths. During this time, the cold liquid also is injected into the other chamber, removing heat and contracting the gas. During this second portion, i.e., the adiabatic portion of the compression cycle, the inertia of the liquid in the chamber assists in the gas compression. Thus, liquid flows up the return path leading to the other chamber past the one-way valve and into the chamber. On the next cycle, the cold line of the first chamber and the hot line of the other chamber are acted upon. This time the liquid flow is down the other leg of the Y-connection, but again passes through the work flow chamber in the same direction continuing the rotation of the turbine. It is to be observed that the pumps do not pump the liquid across the turbine, but merely pump liquid from the bottom of the liquid section to the top of the gas section and the pressure of the gas is changed by the fact that a mist or droplets of hot or cold liquid hits the gas. Thus, the pumps do not see the turbine counter force. As for the turbine, all that the turbine sees is the liquid passing through the work flow chamber going from the Y-connection to the return lines.
HOT LIQUID AND WASTE HEAT RECOVERY
In the operating sequence just described, the hot liquid supplied into the chamber by the nozzle should be metered, since if excessive liquid is thrown into the chamber, the heat produced by this excessive liquid is just wasted. Thus, only enough hot liquid for optimum operation is thrown into the chamber and no more. The simplicity of operation and efficiency may be greatly enhanced by recovering the hot liquid and also recovering the waste heat. The hot liquid recovery is shown in FIG. la, where only one of the insulated chambers is shown. In the chamber 13 is a hot liquid nozzle 15 having a multitude of small vertical apertures for spraying the liquid horizontally across the chamber. Opposite to hot liquid spray nozzle 15, is a hot liquid recovery vessel 17 disposed below the level of the spray nozzles to recover the hot droplets sprayed across the chamber. Floating in the chamber 15 is a loose fitting block of insulation 19a, which will permit cold liquid to pass through to the lower chamber, and yet act as a thermal barrier to help maintain the isothermal and adiabatic portions of the cycle. Disposed at the top of the chamber is a cold liquid nozzle 15a which will spray cold liquid downwards. Below this cold liquid spray nozzle is the block of insulation 19a. The cold liquid spray is not recovered, but on the contrary, is sprayed downwards towards the main body of liquid. From the bottom of the hot liquid recovery vessel 17, to the spray nozzle, is a feed forward line 21 having a pump 48e, a heating means 44b and a parallel by-pass line 23. The recovery vessel 17 and the by-pass line 23 have one-way valves 34a, 36a, which are active valves operated by a timing device 25. The by-pass line is necessary to provide a continuous oil flow during the cold cycle of the chamber 13, and thus, reduce the acceleration required during the start and stop portion of the injection cycles. The waste heat recovery is shown in FIG. lb. The heating means 44c is heated by a burner 45 having a fuel input section 47. The heat flows from the burner 45 to the heating means 44c and from there to an absorbent refrigeration system 49 and then is finally exhausted. The absorbent refrigeration system 49 is coupled to the cooling means 46b. The cold liquid from the bottom of the chamber passes through a pre-cooler, then to cooling means and is injected into the chamber from the top of the chamber and sprayed downwards vertically, as described. The hot liquid is recovered from the bottom of the recovery vessel, passes across the feed forward line to the spray nozzle, and is sprayed across the chamber horizontally.
WORKING EMBODIMENT
The theoretical device just described illustrates the 75 principles of operation of the invention herein contemplated. A more practical engine based on these theoretical principles is shown in FIGS. 2 to 4. Thus, there are the two chambers 112 and 114 made from an elongated, narrow, rectangular frame 113. The chambers 112 and 114 are defined by an insulated wall 115 within the frame. Each chamber has an upper gas section 116, 116a and a lower liquid section 118, 118a. Instead of the Y connection shown in FIG. 1, there is a straight forward passage 122 defined in the base of the frame. This forward passage 122 runs alongside both chambers on one side of the frame. Separating the forward passage from the chambers are reed valves 130. These reed valves are one- way valves allowing liquid to go out of the chambers into the forward passage, but not from the forward passage into the chambers. At one end of the engine is the 15 work flow chamber 124, having a turbine and an output shaft 125. Along the other side of the frame is a return passage 128, similar to the forward passage, also connected to the work flow chamber 124, and again, this return passage is separated from the chambers by reed valves 134. As best shown in FIG. 3, these reed valves 134 permit one-way flow into the chambers. Each chamber has a hot and a cool flow line 140, 142. Each line has a pump 148a, 148b and the hot flow lines have a heater 144, while the cool flow lines have a cooling coil 146. Each chamber has a suitable liquid, such as silicon fluoride oil, in the liquid section and a suitable gas, such as argon gas, in the gas section. The working embodiment just described works just like the theoretical machine previously described. There is a distributor timer 152, shown greatly magnified in the drawing. This can either be a mechanical cam or solid state electronic timer. The timer acts on one hot and one cold line simultaneously spraying hot and cold liquid in the respective chambers. The gas accordingly expands in the one chamber and contracts in the other, forcing liquid out of the chamber into the forward passage and bringing liquid into the other chamber from the return passage across the work flow chamber. Preferably, the feed to the work flow chamber is across auxiliary lines 154, which can properly guide the fluid flow across the chamber. If necessary, a whirling impeller can be used in the gas section to enhance the breaking up of the injected fluid. However, a good spray nozzle, such as a sonic spray nozzle, may be mounted in the outlet part of the lines into the gas chamber which sprays droplets of oil into the chamber in which case no whirling impeller is needed.
As shown in FIG. 2a, the efficiency of the engine can be enhanced by providing a simulated flywheel effect. This is accomplished by using active valves with enabling means, e.g., solenoid actuated electro- magnetic valves. Thus, valves 130a and 134a are opened and closed by means of a solenoid 135 connected to the timer 152.
It is to be observed, therefore, that the -present invention provides for an engine having at least two chambers 12, 14; 112, 114, each chamber having a gas and a liquid section 16, 18; 116, 118. Hot and cold pump lines which include appropriate pumps, and heating and cooling means, e.g. , 40, 42; 140, 142 are disposed to pump liquid from the liquid section to the gas section, either of the same chamber, or of another chamber. Connected to each liquid section across one-way valves outwards and inwards is a forward passage and a return passage 22, 122; 28, 128 with a work flow chamber 124 inbetween. A distributor timer 52, 152 is connected to each pump line to sequentially pump liquid across a hot or cold line from the liquid section to the gas section of the chambers, the expansion and contraction of gas in these chambers -forcing oil to pass out through the forward passage across the work flow chamber and back to another chamber through the return line.
Should the pumps for one chamber fail to function, the engine will still operate, however with reduced efficiency. In other words, the second chamber acts as a reservoir.
For the purpose of giving those skilled in the art a better understanding of the invention, the following technical data is provided:
TABLE Volume of expansion chambers-200 cu. in. (total for two) Compression ratio-3.1 Speed-1,200 cycles/min. Hot oil temperature-600 F. Gas-argon; Oil-Silicon fluoride Initial gas pressure, p.s.l. (cold) Hot oil Input BA.u.
injected to beater, Output stroke, lbs. B.t.u./br. H.P .00002.00021 .0021. 000-10 .0048.035.0021 .021.0933 636.09 6,614.9 67,416 7.7 15,060 1.12 146, 534 11.52 1. 07X 100 72.0 65,889 2.070 633,456 19.16 2.8X106 92.4
According to the present inventive concept, hot oil 20 mist (or other suitable material) is injected at a controlled rate to obtain essentially isothermal, i.e., constant temperature expansion. The hot gas continues to expand approximately adiabatically, i.e., no heat in or out, in a insulated chamber. Then, cold oil mist is injected at a controlled rate to obtain isothermal compression. The gas is then compressed adiabatically. The advantages of this arrangement are several. Oil mist is used for heat transfer. Thus, there is a large surface area of a rapid heat transfer without loss of working volume. Also, the arrangement allows remote location of heat exchange units, i.e., the heating and cooling units. This also means external combustion, rather than internal combustion. In order to obtain isothermal expansion and compression, there is a controlled heat rate input. Furthermore, other appropriate working curves for the system can be defined and controlled. The oil piston allows the use of fluid mist for the heat transfer without complicated oil recovery methods and also allows the use of insulated expansion chambers. There is no mechanical sliding surface internal to the engine. The production cost for the engine is greatly reduced with a greatly increased reliability and operating life of the engine. No rigid mechanical power transmission system is required. The oil output can be readily controlled and simple hydraulic feed lines can be placed where needed. Furthermore, the system lends itself to a low cost, reliable, silent, hermetically sealed engine that can operate on any heat source. This allows external combustion and fuels, in the case of a boat, truck, or automobile, which can greatly reduce undesirable pollution.
US3791771
PUMP HAVING MAGNETICALLY DRIVEN RECIPROCATING PISTONS
PUMP HAVING MAGNETICALLY DRIVEN RECIPROCATING PISTONS
Inventor(s): ROESEL J
A pump wherein the pumping takes place in an elongated chamber having first and second magnetic material piston members therein, at least one member being moveable and at least said one moveable member having check valve means therein so that liquid is flowed through the check valve means as the members are separating and the relative movement towards each other of the sections closes the check valve means. A unidirectional flow outlet between the members allows the liquid to be pumped out by the relative movement of the piston members. Facing each other on the outside of the chamber are first and second horseshoe electromagnets with first and second coils around each horseshoe. Connected to the first set of coils is an AC to DC converter to supply DC power to the coil, whereas the second coil has a line for connection to an AC source. The first coil, the converter and the second coil are in series so that the first horseshoe magnet presents alternating North and South poles, while the second horseshoe magnet has fixed North and South poles. When plugged into a line, the fixed poles are alternately presented with a similar and a different opposed pole. This causes the moveable piston members to be attracted to the poles on one cycle and be attracted to each other on the next cycle by virtue of the tendency of the pistons to move in the direction of maximum magnetic flux linkage, thus pumping the fluid.
BACKGROUND OF THE INVENTION
The present invention relates to a pump, and more particularly to a pump which can be readily controlled, can work under various temperature conditions, and is small, sealed, and compact, so as to be fitted into a small space.
BRIEF DESCRIPTION OF THE PRIOR ART
Magnetically driven pumps usually have a spring return. Since about one-half of the magnetic force is used to store energy in a spring, the efficiency of such pumps is low, and the piston return is dependent on the spring force.
Because of government incentives in the last few years, considerable efforts have been exerted by inventors to develop anti-pollution engines. Many of these engines are based on the so-called "Carnot Cycle" and derivatives thereof, such as the concepts of Diesel, Stirling, Brayton, Otto, and others. An example of such an engine is that described in the John F. Roesel, Jr., U. S. Pat. application No. 29,601, filed Apr. 17, 1970. Many of these engines require a pumping arrangement between phases, and in some cases, the pump may have to pump in succession a hot and a cold fluid. Heretofore, pumps for this type of work were of a laboratory type. However, if these engines are to be of any practical use, the pumps must be equal to the task and be long lasting. Furthermore, such pumps must be able to operate on a regularly available power source, such as a 60 cycle line or an automobile alternator. Because of the low efficiency of magnetic pumps, these pumps do not seem to be the type desired.
Although attempts may have been made to provide such a magnetic pump, none, as far as I am aware, have been very successful in practice. Yet, the present invention is directed to a high efficiency magnetic pump free of the foregoing defects.
SUMMARY OF THE INVENTION
Briefly stated, the present invention contemplates a pump wherein the pumping takes place in an elongated chamber having first and second magnetic material piston members therein, at least one member being moveable and at least said one moveable member having check valve means therein so that liquid is flowed through the check valve means as the members are separting and the relative movement towards each other of the sections closes the check valve means. A unidirectional flow outlet between the members allows the liquid to be pumped out by the relative movement of the piston members. Facing each other on the outside of the chamber are first and second horseshoe electromagnets with first and second coils around each horseshoe. Connected to the first set of coils is an AC to DC converter to supply DC power to the coil, whereas the second coil has a line for connection to an AC source. The first coil, the converter and the second coil are in series so that the first horseshoe magnet presents alternating North and South poles, while the second horseshoe magnet has fixed North and South poles. When plugged into a line, the fixed poles are alternately presented with a similar and a different opposed pole. This causes the moveable piston members to be attracted to the poles on one cycle and be attracted to each other on the next cycle by virtue of the tendency of the pistons to move in the direction of maximum magnetic flux linkage, thus pumping the fluid.
The invention, as well as other objects and advantages thereof will become more apparent from the following detailed description when taken together with the accompanying drawings, in which:
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a schematic electrical explanation of the inventive concept;
FIG. 2 is a perspective exploded view of a pump according to the concept of FIG. 1;
FIG. 3 shows a type of check valve and piston arrangement particularly useful with the pump contemplated herein;
FIG. 4 is a cross-sectional explanation of the check valve depicted in FIG. 3,
FIG. 5 is a schematic explanation of a modified version of the invention, and
DETAILED DESCRIPTION
Theoretical Device
Shown in the drawing is an elongated chamber 11 of non-magnetic material containing sealingly reciprocating paramagnetic piston members 13 and 15 at both longitudinal ends. These metal members are made of a magnetic material and have an aperture with a check valve 17, 19 therein. Towards the center of the chamber 11 is an output port with a check valve 23. At the ends of the chamber 11 are input ports 21a and 21b. On one side of the chamber 11 is a first laminated electromagnet assembly 25a with a coil 27a with poles 29a and 31a extending to both sides of the chamber.
Opposite electromagnet 25a is a second laminated electromagnet assembly 25b substantially identical to electromagnet 25a. Second electromagnet 25b also has a coil 27b and poles 29b and 31b. Interposed between one end each of coils 27a and 27b is a diode bridge 33 consisting of four diodes 33a, 33b, 33c, 33d. The output sides of diodes 33a and 33b each face a common midpoint 35a, whereas the input sides of diodes 33c and 33d each receive an input from a common midpoint 35c. Diodes 33a and 33d are poled in the same direction across a common midpoint 35d connected to the input side of diode 33a and the output side of diode 33d. Likewise, diode 33b and 33c are poled in the same direction across a midpoint 35b, connected to the input side of diode 33b and the output side of diode 33c. Coil 27b is connected between midpoints 35a and 35c. The inner end of coil 27a is connected to the midpoint 35d. One side 37 of the AC line voltage is connected to outer end of coil 27a. The other side 39 of the AC line voltage is connected to midpoint 35b.
OPERATION OF THE PUMP
As sides 37 and 39 are plugged into a 60 cycle AC line, voltage in magnetic 25a alternates at 60 cycles and poles .sqroot.a, 31a change in polarity. Meanwhile voltage flowing in magnet 25b is pulsating DC voltage, since it has been rectified in diode bridge 33. Therefore, the poles 29b and 31b in magnet 25b remain fixed while the polarity of poles 29a and 31a change in polarity. Thus, for example on one-half cycle of the 60 cycle AC North pole faces North pole and South pole faces South pole, while on the next one-half cycle the situation is reversed and North pole faces South pole, while South pole faces North pole. While applicant does not wish to be limited by the following analysis, it is theorized that since metal piston members 13 and 15 are paramagnetic, when the poles 29a and 29b, and 31a and 31b are aligned North-South and South-North respectively, the metal members tend to align themselves with the poles by virtue of lines of magnetic force being aligned generally between adjacent poles. When the pairs of opposite poles 29a and 29b, and 31a and 31b are the same polarity, the paramagnetic piston members tend to be attracted to each other by virtue of the lines of magnetic force being aligned generally between laterally spaced-apart poles, e.g., poles 29a and 31a, and 29b and 31b. The check valves 17, 19 on metal members 13, 15 allow fluid to flow towards the central output port 23 as the pistons 13 and 15 reciprocate, but not towards the inlet ports 21a, 21b. Thus, fluid is pumped between the inlet ports 21a, 21b through outlet port 23.
PRACTICAL EMBODIMENT
A practical embodiment of the inventive concept is depicted in FIG. 2. Here, the part numbers are in the hundred series, but generally the part number in the hundred series correspond to those in the tens series of FIG. 1. Thus, the cylindrical elongated chamber 111 of FIG. 2 corresponds to elongated chamber 11 of FIG. 1. Fluid, e.g., water is fed to both ends of chamber 111 by a pipe 112 connected to one inlet port 121a, which in FIG. 2 is above the chamber end. Pipe 112 is fastened to inlet port 121a by a joint or union 114. Also, fluid is carried to the other inlet port 121b by a curved duct 116 from the first inlet port. Within the cylindrical elongated non-magnetic chamber 111 are cylindrical paramagnetic piston members 113 and 115. These piston members 113 and 115 each have a fast acting check valve arrangement which consists of a non-paramagnetic drum section 118 having peripheral apertures 120. Thus, fluid entering inlet port 121a will flow through these apertures 120. On the inner side of the drum section 118 is a disk shim 119 mounted on a central axle (not visible) and held by a stop 117. As the pistons 113 and 115 move toward one another fluid trapped on the inner side between the pistons push the shim 119 against the apertures 120 thereby effectively providing for positive displacement of fluid outwardly through check valve 123. As the pistons 113 and 115 move away from one another fluid on the outer side will push through the apertures 120 against the shim 119 pushing the shim away from the apertures 120 thereby allowing fluid on the outward side of the pistons to flow inwardly thereof providing an intake stroke in preparation for the inward discharge stroke of pistons 113 and 115. On the inner side of paramagnetic piston members is a second paramagnetic drum section 122, also with apertures 124 corresponding somewhat to apertures 120 but shim 119 can not seat against apertures 124 on the intake stroke because of stop shoulder 117, see FIG. 4. However, much more important is the peculiar comb-like construction of second drum section 122. This drum is made of individual laminations 126, which may be made by slotting the solid pieces, and is tied to the drum base with air gaps in between and a vertical aperture 126a at the outer end. The slotting or lamination is to increase the magnetic permeability of this paramagnetic drum section so as to properly align this section up with the poles 129a and 131a, and 129b and 131b of the electromagnets 125a and 125b respectively. The vertical aperture 126a allows the pumped fluid to rapidly enter the pump outlet. These horseshoe electromagnets 125a, 125b, have each of their two poles 131a and 131b encircled by a pair of coils 127a, and a pair of coils 127b respectively. The poles 131a, 131b having a curved pole face 128 whose radius of curvature corresponds to the outer wall of chamber 111. The laminar electromagnets 125a and 125b are held together in assembled relation by bracket pieces 130 and screws 132 and the cylindrical chamber 111 is sealed with end walls 134, only one of which is shown held to the chamber wall by screws 136, only one of which is shown. The end walls 134 have springs 138 tending to impel the metal members 113, 115 inwards. The object of these springs is 0merely to keep the metal members from striking and possible sticking to the chamber closures 134. The pump outlet is through a central pipe 140 having a check valve 123 therein. This check valve 123 can be similar to that shown in FIG. 3. Thus, in practice, the check valve is a free floating disk guided by a cylindrical section through a center aperture in the disk of such length as to allow surface movement from the seating surface to a stop which restricts the disk movement to a designed maximum open position. The seating surface of the disk is on a low friction, self lubricating guide containing appropriate passages for fluid flow contained within the outer periphery of the disk.
Also, as hereinbefore pointed out, magnetically driven spring return pumps cannot supply a pumping pressure equal to the magnetic force, as approximately one-half of the force is used to store energy in a spring to return the piston to the starting position for the next magnetically driven stroke. However, the maximum pressure available in the pump herein described, which is limited only by the magnetic flux that can be produced, is approximately twice the pressure that is available in a pump where the piston or diaphram is returned by spring action.
As shown in the alternate embodiment of FIG. 5, the two check valves 217a and 219a can allow passage in the same direction. Thus, the input is at one end and the output at the other end of the chamber 111a.