US3611876A

US3611876A - Ultra high-pressure compressible fluid motor

Info

Publication number: US3611876A
Application number: US850084A
Authority: US
Inventors: Luther F Day
Original assignee: Individual
Current assignee: FERRIS Q DAY
Priority date: 1969-08-14
Filing date: 1969-08-14
Publication date: 1971-10-12
Anticipated expiration: 1988-10-12

Abstract

A motor utilizing a plurality of pistons reciprocating longitudinally in a rotating piston barrel is disclosed. Rotation is developed by the force of the pistons against an angled ramp plate. An apertured seal pad completes the bottoms of the cylinders and bears against a port ring having circumferentially disposed slots and ports specifically located therein to permit the transfer of the compressible fluid and an incompressible fluid to and from the individual cylinders at appropriate points in the operational cycle. A lubricating seal between each piston and its cylinder wall to contain the extremely high pressures at which the motor is adapted to operate is provided by a plurality of oil rings which are established automatically during the rotation of the piston barrel.

Description

United States Patent Luther F. Day

[72] Inventor Hawthorne, Calif. [21] Appl. No. 850,084 a [22] Filed Aug. 14, 1969 [45] Patented Oct. 12, 1971 [73] Assignees Ferris Q. Day; Harvey E. Day

[54] ULTRA HIGH-PRESSURE COMPRESSIBLE FLUID MOTOR 24 Claims, 13 Drawing Figs.

[52] US. Cl 9l/6.5, 91/46, 91/484, 91/499 [51] Int. Cl FOlb 3/02, F01b 13/04 [50] Field of Search 91/40, 176, 499, 6.5, 484; 92/154, 156, 159,160

[5 6] References Cited UNITED STATES PATENTS 2,698,604 1/1955 Edwards 91/46 Shaw Primary Examiner-Paul E. Maslousky Attorney-Henry M. Bissell ABSTRACT: A motor utilizing a plurality of pistons reciprocating longitudinally in a rotating piston barrel is disclosed. Rotation is developed by the force of the pistons against an angled ramp plate. An apertured seal pad completes the bottoms of the cylinders and bears against a port ring having circumferentially disposed slots and ports specifically located therein to permit the transfer of the compressible fluid and an incompressible fluid to and from the individual cylinders at appropriate points in the operational cycle. A lubricating seal between each piston and its cylinder wall to contain the extremely high pressures at which the motor is adapted to operate is provided by a plurality of oil rings which are established automatically during the rotation of the piston barrel.

PATENTED nm 1 21971 SHEET 1 BF 3 FIG.2

INV/zN'I'OR. LUTHER F. DAY

ATTORNEY PATENTED 0m 1 21971 SHEET 2 [IF 3 ATTORNEY PATENTED um I 2 IHYI SHEET 3 [1F 3 REGENERATOR RAMP PLATE GAS SOURCE EXPANSION ExHAusT- -sAs INJECTION PISTON cusmou OIL maacnou CLOSED INVIZN'I'OR. F 2 LUTHER F. DAY

ATTOR N EY ULTRA HIGH-PRESSURE COMPRESSIBLE FLUID MOTOR BACKGROUND OF THE INVENTION l. Field of the Invention This invention relates to rotary power developing devices, and more particularly to a rotary motor driven by a compressible fluid.

ll. Description of the Prior Art Interest in steam engines as a power plant for general automotive use is presently being revived after a hiatus of some 50 years or more. New developments in compact steam power plants which show some promise of making the steam engine competitive with reciprocating and other types of gasoline and diesel engines have been a factor in this renewed interest. However, of major importance is the problem that has been continually developing with respect to the conventional automobile engine as a principal source of air pollution. Internal combustion engines are presently blamed for some 85 percent of total air pollution. Even though pollutant emission controls are imposed, the emission rates are still on the order of 200 to 250 parts per million p.p.m.

Steam engines with external combustion give promise of corresponding emission levels in the range of 30 to 60 p.p.m. in the near future, plus the possibility of reducing these emission levels even further with continued research and development. As a further advantage, such external combustion burners could handle kerosene or low octane gasoline without the antiknock and other conditioning agents that are believed responsible for a particularly toxic group of reaction products in metropolitan smog. The original automotive steam engines ran in the open-cycle mode. Although the early steam autos, such as the Stanley Steamer, may have provided a number of desired performance characteristics, they were not suitable for extended trips because of the necessity of replacing their water supply at frequent intervals.

As far as is known, the present efforts at developing a steam power package for general automotive use have been directed at combining more or less standard steam engine configurations with innovations in the condenser or regenerator apparatus which avoid the need for frequent water reserve replenishing. However, such engines still utilize a reciprocating piston-piston rod-crankshaft concept which does not present any promise of improvement with respect to the number and complexity of the parts, the need for regular maintenance, and the inherent high frictional losses.

Motors are known which operate on the principle of reaction to the expansion of a compressible fluid other than steam. Compressed air motors are utilized in reciprocating tools and other apparatus. However, such devices are typically operated at relatively low pressures (generally not in excess of 150 pounds per square inch) and are relatively small in size, even though they may be powerful for their size. As far as is known, other than my own efforts in this direction, the development of a rotary motor concept capable of operating on steam or any other compressible fluid, particularly at ultra high pressures such as in excess of 5,000 p.s.i., and producing sufficient power to drive a standard automobile or to be used as a power source in large stationary power stations has not been realized.

SUMMARY OF THE INVENTION ln brief, the present invention provides a plurality of floating, reciprocating pistons mounted in circumferentially disposed cylinders which are longitudinally (axially) directed relative to the rotation of a barrel containing the cylinders. Rotational torque is developed by the pistons bearing against a ramp plate, the rotational axis of which is maintained at a slight angle to the rotational axis of the piston barrel. As the barrel rotates, an opening at the base of each cylinder in turn moves past a series of ports mounted in an adjacent port ring. These ports are circumferentially arrayed within the port ring and comprise, in order, an oil port, a gas port, and an exhaust port. With the piston near the bottom of its stroke, when its cylinder is adjacent the oil port, the lower portion of the cylinder receives a predetermined amount of oil injected at relatively low pressure which is controlled in accordance with an aspect of the invention, by the oil pressure and effective size of orifice to determine the number of expansions of the compressible fluid. Without substantial axial movement of the piston, the cylinder then moves adjacent the gas port where the remaining space in the cylinder not occupied by the recently injected oil is filled with compressed gas at high pressure and then immediately cut off from the compressed gas source. The compressed gas then expands within the cylinder, driving the piston longitudinally outward against the ramp plate and doing work against the piston for up to approximately 180 of rotation. At that point the cylinder is adjacent the exhaust port which extends circumferentially for approximately and, as the rotation of the piston barrel continues, the piston is driven longitudinally back into the cylinder by the angled ramp plate, exhausting most of the gas from the cylinder through the exhaust port. At the termination'of the exhaust port, further escape of gas from the cylinder is blocked in order that what little gas remains may be compressed to form a cushion which prevents the piston from hitting the bottom of the cylinder. Basically, my invention utilizes the concept of employing two fluids, one a compressible gas at extremely high pressure, the other a noncompressible liquid at relatively vlow pressure. Both fluidsare injected in succession into a cylinder to control the operation of a piston therein. The liquid, preferably a lubricating oil, is injected initially in a metered flow in order to control the amount of pressurized gas which is admitted into the cylinder and thus the power output of the motor. This provides automatic control of the number of expansions of the pressurized gas without reliance on mechanical apparatus. The lubricating fluid introduced into the cylinders is arranged, in accordance with the invention, to advantageously perform at least four functions. It lubricates the moving parts, specifically the pistons reciprocating back and forth within the cylinders; it provides a liquid seal in conjunction with a particular structural configu' ration of the piston and cylinder so that leakage of the highpressure gas past the piston along the cylinder walls is absolutely prevented and also provides a seal between the piston barrel and the port plate at the base of each cylinder in its rotation about the motor axis; it serves to variably control the power output of the motor by virtue of its control of the volume of the admission space within the cylinder which is available for the injection of the high-pressure gas; and it controls the state of the high-pressure compressible fluid throughout the entire extent of the expansion and exhaust phases and prevents any change of state through condensation or solidification by virtue of the fact that it is maintained at an elevated temperature opposing such change of state.

Motors designed in accordance with the principles of my invention may be operated on steam, on the vapors of liquids which are more volatile than water (as for example a mixture of alcohol and water, ammonia, formaldehyde or the like), or on compressible fluids normally found in the gaseous state, such as carbon dioxide, nitrogen, or the like. An important consideration in realizing the high efficiency which is inherent in motors in accordance with my invention is its capability of handling compressed fluids at extremely high pressure. Steam boilers operating at the critical pressure of water vapor, approximately 3,200 p.s.i. have been operating successfully for a number of years. This pressure corresponds to a temperature slightly in excess of 700 F. Operation at substantially higher pressures is presently feasible with the development of improved high temperature alloys capable of handling the increased temperatures.

With other compressible fluids, greatly increased pressures may be developed. Higher injection pressures permit increased power output and improved efficiency. For example, motors in accordance with the invention capable of operating at 15,000 p.s.i. are easily realized.

In accordance with an aspect of the invention, special booster arrangements may be included to provide additional power for starting or operating under heavy loads. These may comprise one or a series of additional gas ports following the gas port already mentioned for the injection of high-pressure compressible fluid into the cylinders. These additional gas ports may be selectively and sequentially connected to the pressurized gas source in order to provide the equivalent of an extended gas port communicating with the cylinders for a substantial portion of the power phase when extreme power demands are imposed. Under normal operating conditions the booster ports are disconnected from the pressurized gas source in order that the motor may operate at maximum efficiency from he single gas port first mentioned.

It has long been recognized in connection with the operation of steam engines that among the conditions necessary for high efficiency are the following:

I. The steam shall be quickly admitted to the cylinder and as near boiler pressure as possible.

2. The steam should be cut off very sharply, quite early in the stroke.

3. Prerelease of the steam should be at a minimum and, to the extent necessary, should occur as late as possible in the stroke without increasing the back pressure.

4. Exhaust of the steam should occur with a minimum of back pressure.

5. The steam should be compressed within the cylinder no more than is necessary to absorb the momentum of the reciprocating parts and fill the clearance space, at a pressure most suited to the conditions of operation.

6. The clearance space within the cylinder should be kept at a minimum.

Although the various factors relating to improvement of efficiency in steam engines recognize that efficiency may be improved by reduction of clearance, it has also been recognized that some minimum clearance is absolutely essential in the design of conventional steam engines. Generally, in such prior art steam engines as are known, the number of of expansions which are permissible in a given cylinder configuration is limited because of the danger of condensation as the steam expands with the resultant danger of development of a slug of water in the clearance space which, because it is incompressible, may force the end off the cylinder from the driving force of the piston. Furthermore, clearance must be maintained so that the piston does not strike the cylinder heads. it has been said that the clearance volume of an engine cannot be eliminated because it is impossible to provide steam and exhaust ports without volume. However, arrangements in accordance with my invention are capable of operating with zero effective clearance and the usual reasons given for requiring some definite clearance space are not applicable in my design.

In particular arrangements in accordance with the invention, the quantity of oil which is injected into each cylinder during its operating cycle is variable, depending upon the motor load. The amount of oil injected determines the space which is available for the injection of compressible fluid. For example, if the admission volume at the base of the cylinder when the piston is fully retracted (bottom dead center) is completely filled with oil, there is no room for the injection of compressible fluid and as a result the piston will do virtually no work during the following cycle. Conversely, if no oil is injected into the cylinder admission volume, the maximum amount of compressible fluid will be injected with the result that the piston performs its maximum work during the remainder of the power phase of the cycle. For a given structure, the amount of compressible fluid which is injected into the cylinder may be varied from zero to the full admission volume under the control of the incompressible fluid which is injected at bottom dead center, thereby controllably varying the number of expansions experienced by the compressible fluid during the power phase of the piston cycle.

In accordance with another aspect of the invention, the incompressible fluid, typically oil, which is injected into the cylinder for the purposes of lubrication, sealing and admission volume control, as already described, may also be utilized to supply heat to the compressible fluid in the cylinder during expansion. ln the case of steam as a compressible fluid, there is a tendency for initial condensation to occur as well as condensation later in the stroke as the compressible fluid undergoes numerous expansions. Or in the case of compressible fluids other than steam as the working fluid, the reduction of temperature due to expansion may result in an icing upi.e., a change from a gaseous state to a solid state-rather than a change to a liquid state as in the case of condensation. As mentioned, the incompressible fluid which is employed with the compressible fluid in the operation of the motor, maintains the minimum temperature in the cylinder above the point at which the change of state from a gas to a liquid or a solid is likely to occur. Moreover, the structural configuration of the compressible fluid injection chambers helps to minimize the problem of initial condensation. Strictly speaking, in the structural configuration of arrangements in accordance with the invention, there are no inlet or exhaust passages as such. injection of the compressible fluid occurs without reduction in pressure and lasts for only a very small portion of the operating cycle. Cutoff is sharp and immediate, without any wire drawing. The power stroke lasts for a full 180 of the cycle, extending from bottom dead center to top dead center of the piston travel, and the exhaust phase of the operating cycle extends for or more.

The mechanical efficiency of the motor design of my invention is inherently very good. The mechanism is of extremely simple design with low friction and very few moving parts. There are no connecting rods, crankshafts, cylinder valves, camshafts, timing gears or belts, nor any of the other complex components commonly employed in previously known mechanical motors and engines. No externally controlled mechanical apparatus is required for the variable control of the number of expansions of the working fluid which is provided as a feature of the invention. Despite the ultrahigh pressures involved, metal-to-metal contact is avoided with all mov ing surfaces sliding on a film of oil.

In accordance with an aspect of my invention, the reaction forces of the high pressure gas are substantially balanced except for a slight net force biasing the piston barrel against its seal pad. This net biasing force is automatically maintained, regardless of the working pressures employed, by judicial determination of the effective areas against which the pressures are applied into opposite directions, The desired biasing force when the motor is at rest is supplied by a biasing spring, thus ensuring the proper seal of the pressure chambers when high-pressure fluid is initially admitted during startup.

The only moving parts are the pistons which reciprocate longitudinally within the piston barrel and the piston barrel itself which rotates about a central shaft. The angled ramp plate rotates in contact with the outer ends of the pistons, and is supported on a conventional roller bearing structure.

The pistons slide within the cylinders on a film of oil which both seals and lubricates the mechanism. ln accordance with the invention, each piston is constructed with a plurality of small circumferential grooves which fill with oil during the operation of the motor. A communicating groove is fashioned within the cylinder, extending longitudinally along the radially outward line of the cylinder from the bottom of the cylinder to at least the position of the outermost piston groove when the piston is retracted. This ensures that oil is directed to the oil grooves in any attitude of the motor because of the centrifugal force resulting from piston barrel rotation. As speed increases, lubricating oil pressure adjusts accordingly. By virtue of this arrangement which takes oil for lubrication and sealing from the supply injected into each cylinder for control of the gas admission space, the need for a separate pressurized lubricating system is eliminated.

In accordance with a further aspect of the invention, particular arrangements in accordance therewith are designed to provide a cushioning effect during a portion of the stroke when the piston is approaching bottom or its fully retracted position. Because the piston is not attached to the ramp plate, and because the point of piston contact at the ramp plate follows a sine wave function with respect to piston travel, there is a tendency for the piston, once it reaches maximum velocity on the exhaust stroke, to leave the contact with the ramp plate with a consequent possibility of impacting with the bottom of the cylinder. To prevent this, I provide a termination of the exhaust port at a point such that a small amount of compressible fluid remains in the cylinder. This is blocked momentarily during the continued travel of the piston with a result that a cushion is developed which prevents the piston from bottoming in the cylinder. The cylinder continues its rotational travel and immediately after the cushioning phase enters into communication with the slot containing the incompressible fluid at relatively low pressure. Because of the possibility that the cushion pressure in the cylinder may exceed the pressure of the incompressible fluid, I provide an arrangement for absorbing such a pressure pulse as may occur under such circumstances. This is in the form of a dead end tube communicating with the line supplying incompressible fluid to the motor and containing a compressible fluid so as to absorb any transient pressure from the cylinder which is in position at the incompressible fluid slot.

It will be noted that arrangements in accordance with the invention utilize an incompressible fluid in combination with a compressible fluid, both existing within the cylinder together. In conventional steam engines of the prior art, it was imperative that such a mixture of an incompressible fluid with the compressible steam be avoided. This was one of the reasons why a substantial clearance volume was required, in order to provide enough space for the existence of such water as might be condensed within the cylinder during operation, without having the piston push the end out of the cylinder. In arrangements in accordance wit the present invention, the structural configuration of the exhaust chamber and the extent of the exhaust port which is open to the cylinder during a substantial portion of the return stroke of the piston, makes it inconsequential whether there is an incompressible fluid, such as oil or condensed vapor, in the cylinder or not. If there is, it will be automatically expelled through the exhaust porting which is continuously open for nearly all of the return stroke of the piston.

A better understanding of the invention may be had from a consideration of the following detailed description, taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a plan view of one particular arrangement in accordance with the invention;

FIG. 2 is a sectional view taken along the line II-II of FIG. 1 and including a partial section of a particular portion thereof; 1

FIG. 3 is a view showing the port plate of the motor of FIG. 1, and is taken along the line III-III thereof, looking in the direction of the arrows;

FIG. 4 is a sectional view of a portion of the port plate of FIG. 3, taken along the line IV-IV and looking in the direction of the arrows;

FIG. 5 is a view, partially broken away, of the piston barrel in the arrangement of FIGS. 1 and 2, looking from the righthand end thereof;

FIG. 6 is a sectional view of the piston barrel of FIG. 5 taken along the line VIVI;

FIG. 7 is an end view of the piston barrel of FIGS. 1 and 2 as viewed from the left-hand end.

FIG. 8 is a view of a piston such as those mounted in the piston barrel of FIGS. 5-7;

FIG. 9 is a schematic view showing a section through a portion of a cylinder with the admission volume partially filled with incompressible fluid FIG. 10 is a schematic view similar to FIG. 9 showing the admission volume at the bottom of the cylinder almost entirely filled with incompressible fluid;

FIG. 11 is a block diagram of a system employing the motor arrangement of FIG. l;

FIG. 12 is a curve showing piston travel during rotation of its corresponding cylinder through the various phases in an operating cycle of the arrangement of FIG. 1; and

FIG. 13 is a schematic view showing a particular modification to develop power boost in the arrangement of FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT As shown in FIGS. 1 and 2, a particular motor 10 in accordance with the invention may comprise a base housing 12 and an end housing 14 fastened together on opposite sides of a central port plate 16. Supported within the base housing 12 is a shaft 20, positioned in bearings 22 within the base housing 12 and extending into the end housing 14 where it is supported by another bearing member 24. As shown, the bearings 22 are of the ball bearing type, although roller bearings may also be employed; the bearing 24 may be a bushing or a pin bearing. The shaft 20 is splined near the right-hand end 26 for engaging a piston barrel 28, shown in greater detail in FIGS. 5-7. The piston barrel 28 at its left-hand end (considered the bottom herein) faces against the port plate 16, against which it rotates about the longitudinal axis of the shaft 20, driving the shaft 20 with it in rotation by virtue of the splined engaging arrangement of the two elements. The piston barrel 28 contains a plurality of cylinders such as 30 extending longitudinally parallel to the axis of the shaft 20 and disposed circumferentially thereabout. As assembled, each cylinder 30 contains a piston 32 of the configuration such as is shown in FIG. 8. The pistons 32, during operation of the motor, are in contact with an angled ramp plate 34 which is arranged for rotation about an axis which in a preferred embodiment is aligned approximately 15 from the axis of the shaft 20. A roller bearing arrangement 36 supports the ramp plate for rotation with the pistons 32 as the piston barrel 28 itself rotates.

As may be better seen in FIGS. 5-7, the piston barrel 28 contains a plurality of cylinders 30 (in this instance 15 cylinders) in which pistons such as piston 32 of FIG. 8 are mounted. These pistons may be readily inserted from the top end of the piston barrel as shown in FIG. 5. The bottom end of each cylinder as viewed in FIG. 7 is partially closed, except for an admission port 31. It will be noted in FIG. 6 and the broken away view in FIG. 5 that each cylinder 30 is provided with longitudinal groove 38 extending generally from the bottom of the cylinder 30 to a point near the open end of the cylinder. The grooves 38 are located along the radially outermost side of the cylinders 30. As shown in FIG. 8, the piston 32 is provided with a plurality of grooves 40 which extend circumferentially about the piston 32. These are oil grooves which, when the piston 32 is positioned within a cylinder 30 of the piston barrel 28, communicate with the longitudinal groove 38 and receive oil therefrom. The oil within the grooves 40 serves to lubricate the walls of the cylinder 30 as the piston travels back and forth therein and also advantageously provide a very effective seal against the high pressure of the compressible fluid employed in operating the motor. As the piston barrel 28 rotates during the operation of the motor, centrifugal force advantageously drives oil from the lower end of the cylinder 30 toward the groove 38 along which it extends to communicate with the various grooves 40 of the piston 32.

The port plate 16, best shown in FIG. 3, bears against the lower end of the piston barrel 28 and contains the various passages for admitting and exhausting the compressible and incompressible fluids utilized in the operation of the motor 10. The port plate I6 is provided with three slots extending circumferentially about the center of the shaft 20 at substantially the same radius as the ports 31 of the cylinders 30. An oil slot 44 is provided in a position such that it precedes the bottom dead center (BDC) position by approximately the diameter of the cylinder port 31. In FIG. 3, the dead center line is shown as a vertical line extending through the center of the shaft 20. The oil slot 44 extends approximately 26 of arc L.F.D. is supplied with oil for injection into the cylinders 30 through the ports 31 by a tube 45 and passage 46. Beginning near bottom dead center, a gas slot 48 extends an arcuate distance sufficient to communicate with two of the cylinder ports 31. The gas slot 48 is near enough to bottom dead center to communicate with the admission port 31 of a cylinder 30 at the bottom dead center position. The gas slot 48 receives a compressible fluid at very high pressure by way of a tube 49 and passage 50 for injection into the cylinders 30 after they have received a predetermined amount of oil from the oil slot 44. Beginning past the point of top dead center (TDC) by one diameter of a cylinder port 31 and extending circumferentially to a pointjust short of the beginning of the oil slot 44 is an exhaust port 52 which communicates with an exhaust tube 53 by way of a passage 54. The arcuate distance between the termination of the exhaust port 52 and the beginning of the oil slot 44 exceeds the diameter of the cylinder ports 3] by enough to develop a pressure cushion within the cylinder 30 during piston return. Also shown in FIG. 3 is a lateral extension 45A on the oil tube 45 for the purpose of absorbing pulses of pressure that may be developed within the oil passage 46 during operation of the motor 10.

The piston barrel 28 rotates in a sliding frictional relationship against the adjoining face of the port plate 16. It will be noted from FIGS. 6 and 7 that the cylinder ports 31 are located within a raised face portion (seal pad) 33 of the piston barrel 28. It is this raised surface 33 which slides against the port plate 16, riding on a film of oil maintained between the two bearing surfaces and providing a seal against the leakage of compressible fluid from the cylinder ports 31. The outer periphery of the piston barrel 28 is also raised to bear against the port plate 16 to further stabilize the structure. The piston barrel 28 is provided with relief ports such as 35 and 37 to prevent any of the compressible fluid which might leak into the adjacent sealed regions from being tapped under a condition of pressure buildup which would tend to lift the piston barrel 28 away from sealing relationship with the port plate 16. Also for this purpose, the gas slot 48 may be provided with grooves adjacent thereto and angled outward across the face of the seal pad to counteract the tendency to force the piston barrel away from the port plate.

In order that the piston barrel 28 may be biased slightly against the port plate 16 during operation of the motor 10 without need for reliance on the biasing spring arrangement of FIG. 2, the total area of the seal pad 33 is made slightly smaller (by approximately 1% percent) than the sum total area of all of the cylinder cross sections. As a result, the force directing the piston barrel 28 against the port plate 116 as a result of the fluid pressures within the cylinders 30 is slightly greater than the force exerted in the opposite direction by the same pressures. This condition exists regardless of the magnitude of the pressures employed within the cylinders 30. Thus, despite the extremely high pressures that may be utilized in the compressible fluid driving the motor 10, the net forces between the piston barrel 28 and its supporting surface on the port plate I6 are not excessive, but are always such as to maintain the piston barrel 28 in sealing relationship against the port plate 16.

As shown in FIG. 2 in the partial section of the right-hand end 26 of the shaft 20, the piston barrel 28 is biased toward the left-hand end (the direction of the port plate 16) by a combination of a compressed spring 60 and key 62. The shaft end 26 has a lateral slot 64 for receiving the key 62, after which the spring 60 is inserted into the hollow end 26 in which it is held under compression by a screw 66. In this arrangement, the spring 60 causes the key 62 to bear against the piston barrel 28 to hold the piston barrel against the port plate I6 during the startup of operation. As will be explained, once the motor 10 is operating, the piston barrel 28 is held against the port plate 16 by a balancing of the pressure forces within the mechanism.

In the operation of the motor 10, each cylinder 30 passes from the BDC point (see FIG. 3) moving counterclockwise to receive a pulse of high pressure compressible fluid. In accordance with an aspect of the invention, the amount of the compressible fluid so injected is controlled by the amount of the incompressible fluid already in the cylinder. After leaving the gas slot 48, which extends for perhaps 20 of arc (just enough to permit concurrent communication with two cylinder ports), the cylinder passes through the expansion phase which extends to the remainder of the power stroke, thus providing a power stroke of a full 180 of rotation. This may be seen by reference to FIG. 12. At the top dead center point, the cylinder 30 passes from the expansion phase to the exhaust phase which continues for approximately During this phase, the piston 32 completes substantial portion of its travel to its retracted position. Because it is retracted by virtue of its travel with the rotating ramp plate, it becomes accelerated to a point where it tends to leave the ramp plate and, since it is not fastened to the ramp plate, would hammer against the bottom of the cylinder 30 if some provision were not made to arrest its travel. Accordingly, at the termination of the exhaust slot 52 there is provided a solid portion in the port plate 116 at the radius of the cylinder ports 31 which seals the small amount of compressible fluid remaining in the cylinder 30. This develops a cushion which arrests the travel of the piston 32 and prevents it from bottoming in the cylinder 30. Following the piston cushion portion, the cylinder 30 passes into communication with the oil slot 44. Should there still be any momentum remaining in the piston 32 upon communication between the oil slot 44 and the cylinder 30, the corresponding pressure pulse is absorbed in the oil system by virtue of the tube 45A which provides a resilient chamber in communication with the oil tube 45. Following its passage past the oil slot 44, during which the cylinder receives a controlled amount of incompressible fluid (oil) the cylinder 30 passes through a region in the vicinity of the bottom dead center point which is of sufficient dimension to prevent an overlap via the cylinder port 31 between the high pressure gas slot 48 and the low pressure oil slot 44, after which it repeats the operating cycle.

The number of expansions of the compressible fluid which is developed in the power phase during the operation of the motor 10 is controlled by the extent to which incompressible fluid from the slot 44 is injected into the admission volume in the cylinder 30 when the piston is substantially fully retracted. Control of this space is illustrated by reference to FIGS. 9 and 10. In this manner the power developed by the motor 10 is readily controlled. When maximum load is imposed on the motor 10, a minimal amount of oil 47 is injected into the cylinder from the slot 44 as the cylinder 30 passes thereby. This condition is represented in FIG. 9. Thus when a cylinder 30 passes into communication with the compressible fluid slot 48, there is a maximum admission volume within the cylinder 30 so that a maximum amount of the high pressure compressi ble fluid may be injected therein. As a result, the piston 32 in its outward travel within the cylinder 30 exerts a maximum average force for maximum power output. On the other hand, when the motor 10 is operating under relatively light load, its power output is reduced by causing a relatively large amount of oil 47 to be injected into the admission volume of the cylinder 30 as it passes the oil slot 44. This condition is shown in FIG. 10. As a consequence, there is very little space remaining for injection of the high-pressure gas from the slot 48 and the pressure of this gas is rapidly reduced during the outward travel of the piston 32 by virtue of the large number of expansions of the pressurized compressible fluid within the cylinder 30. It is a very simple matter to control the operation of the motor 10 in this fashion by controlling the flow of the incompressible fluid from the slot 44 into the cylinders 30 as they rotate in communication therewith.

In the block diagram of FIG. ill, a system is shown including the motor 10 and various auxiliary equipment which may be employed to complete the system. A portion of the system dealing with the compressible fluid is shown in the left of the figure whereas the incompressible fluid is directed to recirculate along a path on the right-hand side of the figure.

In the system represented in FIG. 11, the compressible fluid may be stored in a reservoir 72 which connects to the motor 10 through a suitable valving mechanism 73. The incompressible fluid may be stored in a reservoir 74 connected for release to the motor 10 via a valve 75. After passing through the motor 10 during the operation thereof in the manner already described, both the incompressible fluid and the compressible fluid are exhausted together into a sump 77. Although there may be some intermixing the compressible fluid is customarily in the form of a gas while the incompressible fluid is a liquid. Separation of the two due to differences in specific gravity of the two fluids may occur within the sump 77 from which the respective fluids are withdrawn. The compressible fluid passes from the sump through a regenerator stage 78 if closed circuit operation is employed, after which the fluid passes to the reservoir 72 for recirculation. In optional form, the compressible fluid may simply be exhausted to atmosphere without regeneration through the regenerator stage 78. If steam is employed as the compressible fluid, the regenerator 78 may include a condenser, a boiler and other apparatus necessary to restore the compressible fluid to the conditions required to drive the motor 10. The incompressible fluid is drawn from the sump 77 through a recirculating pump 80 to the reservoir 74 for continued recirculation.

FIG. 13 illustrates an alternative modification to the port plate depicted in FIG. 3 which may be provided to develop a power booster arrangement in accordance with an aspect of the invention. FIG. 13 shows a portion of the port plate 16 containing the gas slot 48 to which a plurality of

booster slots

48A, 48B, and 48C have been added. All of the slots depicted are arcuately located to communicate with the cylinder ports 31 of the piston barrel 28. Each of the depicted slots, such as 48C, communicates with a source of pressurized compressible fluid 72 via a valve 73 and individual connecting tube, such as 49C. The valve 73 is arranged, by the construction of its rotatable central member 76, to provide selective communication with one or more of the

tubes

49, 49A, 49B, and 49C from the gas source 72 by virtue of the setting of the member 76.

In use, for operation of the motor 10, the valve 73 of FIG. 13 is customarily set to direct pressurized compressible fluid to the gas slot 48 alone. Operation in this manner provides for the maximum number of expansions for the particular quantity of gas injected into a cylinder. However, there may be conditions of operation where it is worthwhile to give up efficiency to develop more torque or power. This may occur during starting up under load or operating under overload conditions. In such an event, additional gas slots may be cut in in sequence or all together by suitably setting the member 76 of the gas valve 73. Such additional gas slots, as 48A for example, when pressurized provide additional injection of compressible fluid to the cylinders 30 at additional points during the power phase, thus increasing the mean effective pressure within the cylinders for developing increased torque and power. As soon as the condition requiring the additional torque operation is terminated, the valve 73 may be restored to a condition where the member 76 directs pressure from the source 72 to only the tube 49 connected to the primary gas slot 48, thus returning the motor to its condition of maximum efficiency and economy.

By virtue of the novel arrangements shown and described herein, a particularly effective form of motor is realized. This motor is capable of operating under extremely high pressures, although the structural configuration employed serves to contain these pressures without the need for undue forces to be applied. A plurality of cylinders are compactly contained in operating relationship such that the power stroke of each piston extends through an entire 180 of an operating cycle. Operation is extremely smooth because of the fact that a large number of cylinders are developing power concurrently. The sealing and lubrication of the pistons within the cylinders of the motor is effected by the oil grooves provided in the pistons which utilize part of the oil injected into each cylinder during a portion of each cycle. This oil in addition to scaling, lubricating and controlling the power output of the motor, also may be utilized to transmit heat into the cylinders to maintain the temperature thereof at a level such as to prevent the compressible fluid in the cylinders from changing state, i.e., changing to either a liquid or a solid. The construction of the individual cylinders and of the motor as a whole is such as to entirely eliminate the necessity for providing a clearance space within the cylinders, as is generally required in conventional steam engines. The same cylinder port is used in each cylinder for both intake and exhaust and may be located concentrically or eccentrically relative to the axis of the cylinder to provide the desired communication between the cylinder and the various ports providing compressible fluid, incompressible fluid and exhaust for the cylinder at various points in the operating cycle.

Although there have been described above specific arrangements of an ultra high pressure compressible fluid motor in accordance with the invention for the purpose of illustrating the manner in which the invention may be used to advantage, it will be appreciated thatthe invention is not limited thereto. Accordingly, any and all modifications, variations or equivalent arrangements which may occur to those skilled in the art should be considered to be within the scope of the invention.

What is claimed is:

l. A pressure-driven motor comprising:

a rotatable shaft;

a piston barrel engageably mounted on said shaft for rotation therewith, said piston barrel including a plurality of cylinders extending substantially parallel to said shaft and substantially equally spaced at a fixed radial distance from the center of rotation of the barrel, each of said cylinders containing a piston positioned for reciprocating 1 motion therein;

a rotatable ramp plate having its axis of rotation angled at an acute angle with said shaft and intersecting the center line of said shaft and positioned to engage the outermost end of each piston as it reciprocates within its cylinder, the ramp plate rotating with said pistons as the pistons and piston barrel rotate around the shaft; and

a port plate having a surface bearing against a facing surface of the piston barrel and containing a plurality of slots spaced about the center of the shaft at a radial distance such as to permit communication between said slots and said cylinders as the piston barrel rotates, the port plate including means for injecting a predetermined amount of an incompressible fluid into each cylinder, means for filling the remainder of the space in said cylinders with a pressurized compressible fluid, and means for exhausting both of said fluids from the cylinders.

2. A motor in accordance with claim I wherein said incompressible fluid is a lubricating liquid.

3. A motor in accordance with claim 1 wherein each of said cylinders includes an oil groove extending along a substantial portion of the length of the cylinder at the outer radial edge thereof and communicating with the base of the cylinder.

4. A motor in accordance with claim 3 wherein each of said pistons has a plurality of circumferential grooves communicating with the corresponding cylinder groove during at least a portion of the operating cycle so as to receive lubricating liquid therefrom and develop a series of liquid seals which also lubricate the surfaces of the cylinder and piston.

5. A motor in accordance with claim I wherein each of said cylinders terminates at its base in a wall portion of the piston barrel having a cylinder port opening reduced in size relative to the cylinder diameter for the admission and exhaust of fluids to and from the cylinder.

6. A motor in accordance with claim 1 wherein the aggregate area of the cylinder cross sections is slightly greater than the area of the facing surface of the piston barrel bearing against the port plate in order to develop a net biasing force urging the piston barrel against the port plate during operation of the motor.

7. A motor in accordance with claim 6 further including a mechanical biasing member and means engaging said member with the piston barrel to develop a biasing force urging the piston barrel against the port plate.

8. A motor in accordance with claim 1 wherein said piston 5 barrel includes at least one relief port extending from an enclosed volume between the piston barrel and the port plate to the outside of the piston barrel to relieve pressurized fluid from said enclosed volume.

9. A motor in accordance with claim 1 having an operating cycle wherein the power phase extends for substantially half of the operating cycle and the exhaust phase extends for a substantial portion of the remaining half of the cycle.

10. A pressure-driven motor comprising a plurality of cylinders and contained pistons therein mounted within a rotatable piston barrel;

means for developing rotational torque from the reciprocating movement of the pistons within the cylinders;

means for admitting a pressurized compressible fluid at substantially constant pressure into each of said cylinders in the vicinity of the bottom dead center travel of the piston therein; and

means for injecting an incompressible fluid for controllably varying the volume of said compressible fluid admitted into a given cylinder in accordance with the power-load characteristics of the motor.

11. A motor in accordance with claim wherein said injecting means comprises means for injecting a controlled volume of said incompressible fluid into each cylinder at a point in the operating cycle shortly prior to the point of admission of the compressible fluid into the cylinder.

12. A motor in accordance with claim 10 further including booster means for selectively admitting pressurized compressible fluid into each of said cylinders at a point in the operating cycle following said admitting means.

13. A motor in accordance with claim 12 wherein said booster means includes a plurality of gas ports arranged in succession along the rotational path of said cylinders.

14. A motor in accordance with claim 13 further including variable control means for selectively applying pressurized compressible fluid to one or more of said gas ports.

15. A pressure-operated motor comprising:

a piston barrel mounted for rotational motion and containing a plurality of cylinders radially spaced thereabout, each cylinder containing a piston mounted for reciprocating motion therein, the axes of said cylinders being substantially parallel to the axis of rotation of the piston barrel;

each piston and cylinder combination undergoing an operating cycle in which a preselected volume of incompressible fluid is injected into a cylinder in the vicinity of the point where the piston therein is at bottom dead center, followed by a phase of admission of a compressi- -12 ble fluid at substantially fixed pressure to fill the remaining space in the cylinder, said cycle having an expansion phase for approximately 180 rotation of the cylinder about its axis of rotation and an exhaust phase in excess of of rotation of the cylinder about its axis of rotation in sequence; and

means for converting the reciprocating motion of the pistons to a torque causing rotation of the piston barrel.

16. A motor in accordance with claim 15 further including means adapted to communicate with each of the cylinders during those phases in which fluid is either admitted into or exhausted from the cylinder.

17. A motor in accordance with claim 16 wherein said lastmentioned means comprise respectively an oil port, a gas port, and an exhaust port mounted in a plate bearing against a face of the piston barrel, all of said ports being arcuately positioned at a substantially constant radial distance from the axis of rotation of the piston barrel.

18. A motor in accordance with claim 17 wherein the oil port and the as port are separated from each other by a distance slight y greater than t e diameter of the communication opening in a cylinder so as to prevent the possibility of communication of high-pressure compressible fluid of the gas port with low-pressure incompressible fluid of the oil port through overlap of a cylinder opening.

19. A motor in accordance with claim 17 wherein the exhaust port and the oil port are separated by a space providing a seal of a cylinder in engagement therewith of an extent sufficient to develop a cushion within said cylinder to prevent the piston therein from striking the bottom of the cylinder.

20. A motor in accordance with claim 15 including means for variably controlling the space available in the cylinder for receiving pressurized compressible fluid in accordance with the operating conditions of the motor.

21. A motor in accordance with claim 15 further including means for injecting controllably variable quantities of an in compressible fluid into the cylinder at a predetermined point in the operating cycle in order to control the number of expansions available during the extent of piston travel for the pressurized compressible fluid in driving said piston.

22. A motor in accordance with claim 21 wherein the incompressible fluid is a lubricating liquid, each cylinder and piston including means for developing liquid rings for both lubricating and sealing the sliding surfaces of the piston and cylinder.

23. A motor in accordance with claim 22 wherein the incompressible fluid comprises means for supplying heat into said cylinders to prevent the compressible fluid from changing state during its expansion therein.

24. A motor in accordance with claim 22 wherein the incompressible fluid comprises means for maintaining a heat balance in said cylinders to prevent the compressible fluid from changing state during its expansion therein

Claims

1. A pressure-driven motor comprising: a rotatable shaft; a piston barrel engageably mounted on said shaft for rotation therewith, said piston barrel including a plurality of cylinders extending substantially parallel to said shaft and substantially equally spaced at a fixed radial distance from the center of rotation of the barrel, each of said cylinders containing a piston positioned for reciprocating motion therein; a rotatable ramp plate having its axis of rotation angled at an acute angle with said shaft and intersecting the center line of said shaft and positioned to engage the outermost end of each piston as it reciprocates within its cylinder, the ramp plate rotating with said pistons as the pistons and piston barrel rotate around the shaft; and a port plate having a surface bearing against a facing surface of the piston barrel and containing a plurality of slots spaced about the center of the shaft at a radial distance such as to permit communication between said slots and said cylinders as the piston barrel rotates, the port plate including means for injecting a predetermined amount of an incompressible fluid into each cylinder, means for filling the remainder of the space in said cylinders with a pressurized compressible fluid, and means for exhausting both of said fluids from the cylinders.

2. A motor in accordance with claim 1 wherein said incompressible fluid is a lubricating liquid.

5. A motor in accordance with claim 1 wherein each of said cylinders terminates at its base in a wall portion of the piston barrel having a cylinder port opening reduced in size relative to the cylinder diameter for the admission and exhaust of fluids to and from the cylinder.

8. A motor in accordance with claim 1 wherein said piston barrel includes at least one relief port extending from an enclosed volume between the piston barrel and the port plate to the outside of the piston barrel to relieve pressurized fluid from said enclosed volume.

10. A pressure-driven motor comprising a plurality of cylinders and contained pistons therein mounted within a rotatable piston barrel; means for developing rotational torque from the reciprocating movement of the pistons within the cylinders; means for admitting a pressurized compressible fluid at substantially constant pressure into each of said cylinders in the vicinity of the bottom dead center travel of the piston therein; and means for injecting an incompressible fluid for controllably varying the volume of said compressible fluid admitted into a given cylinder in accordance with the power-load characteristics of the motor.

11. A motor in accordance with claim 10 wherein said injecting means comprises means for injecting a controlled volume of said incompressible fluid into each cylinder at a point in the operating cycle shortly prior to the point of admission of the compressible fluid into the cylinder.

15. A pressure-operated motor comprising: a piston barrel mounted for rotational motion and containing a plurality of cylinders radially spaced thereabout, each cylinder containing a piston mounted for reciprocating motion therein, the axes of said cylinders being substantially parallel to the axis of rotation of the piston barrel; each piston and cylinder combination undergoing an operating cycle in which a preselected volume of incompressible fluid is injected into a cylinder in the vicinity of the point where the piston therein is at bottom dead center, followed by a phase of admission of a compressible fluid at substantially fixed pressure to fill the remaining space in the cylinder, said cycle having an expansion phase for approximately 180* rotation of the cylinder about its axis of rotation and an exhaust phase in excess of 90* of rotation of the cylinder about its axis of rotation in sequence; and means for converting the reciprocating motion of the pistons to a torque causing rotation of the piston barrel.

17. A motor in accordance with claim 16 wherein said last-mentioned means comprise respectively an oil port, a gas port, and an exhaust port mounted in a plate bearing against a face of the piston barrel, all of said ports being arcuately positioned at a substantially constant radial distance from the axis of rotation of the piston barrel.

18. A motor in accordance with claim 17 wherein the oil port and the gas port are separated from each other by a distaNce slightly greater than the diameter of the communication opening in a cylinder so as to prevent the possibility of communication of high-pressure compressible fluid of the gas port with low-pressure incompressible fluid of the oil port through overlap of a cylinder opening.

21. A motor in accordance with claim 15 further including means for injecting controllably variable quantities of an incompressible fluid into the cylinder at a predetermined point in the operating cycle in order to control the number of expansions available during the extent of piston travel for the pressurized compressible fluid in driving said piston.

24. A motor in accordance with claim 22 wherein the incompressible fluid comprises means for maintaining a heat balance in said cylinders to prevent the compressible fluid from changing state during its expansion therein.