Piston apparatus
United States Patent 3894522
A piston apparatus includes at least two double-ended cylinders having perpendicular axes and at least two double-ended pistons mounted for reciprocation in the cylinders. A power disk is positioned between the pistons for rotation about a third axis extending mutually perpendicularly to the axes of the cylinders. A crankshaft is mounted in the power disk for rotation about an eccentric axis extending parallel to and offset from the third axis and includes crankpins extending into the cylinders and rotatably connected to the pistons. In the case of piston apparatus having three or more cylinders, certain of the double-ended pistons are connected to crankpins extending from crankshafts mounted in power disks disposed on both sides of the pistons.
US Patent References:
Double-acting internal-combustion engine
Gigli - January 1929 - 1697723
Triple-cam-drive gasoline engine
King - June 1930 - 1765237
Pump
Hueber - August 1931 - 1820883
Hot-gas piston engine comprising one or more closed cycles
Horowitz et al. - August 1951 - 2564363
MODIFIED INTERNAL COMBUSTION ENGINE
Llwellyn - March 1972 - 3648671
Double-acting internal-combustion engine
Gigli - January 1929 - 1697723
Triple-cam-drive gasoline engine
King - June 1930 - 1765237
Pump
Hueber - August 1931 - 1820883
Hot-gas piston engine comprising one or more closed cycles
Horowitz et al. - August 1951 - 2564363
MODIFIED INTERNAL COMBUSTION ENGINE
Llwellyn - March 1972 - 3648671
Application Number:
05/418978
Publication Date:
07/15/1975
Filing Date:
11/26/1973
View Patent Images:
Export Citation:
Primary Class:
Other Classes:
91/183, 123/54.100, 92/72, 123/197.100
International Classes:
F01B1/00; F01B9/02; F01K25/10; F01B9/00; F01K25/00; F02B75/24
Field of Search:
123/55AA,55R,197R,63 92/68,72 91/183,188
Primary Examiner:
Myhre, Charles J.
Assistant Examiner:
Anderson, William C.
Attorney, Agent or Firm:
Richards, Harris & Medlock
Claims:
What is claimed is
1. A piston apparatus comprising:
2. The piston apparatus according to claim 1 further comprising valve means at each end of each cylinder and means driven by the power disk for operating the valve means in coordination with the reciprocation of the valve means.
3. The piston apparatus according to claim 2 wherein the valve means function to alternately admit pressurized fluid to and to exhaust spent fluid from both ends of both pistons, and further including drive means operatively connected to the power disk for actuation thereby.
4. The piston apparatus according to claim 3 wherein the drive means is further characterized by a series of teeth positioned at substantially equally spaced intervals around the periphery of the power disk and forming the output of the piston apparatus.
5. A piston apparatus comprising:
6. The piston apparatus according to claim 5 wherein the valve means functions to control the flow of pressurized fluid into and the exhaust of spent fluid from both ends of both pistons.
7. The piston apparatus according to claim 5 further including drive means operatively connected to the power disk for actuation thereby.
8. The piston apparatus according to claim 5 further characterized by a series of drive teeth positioned at equally spaced intervals around the entire periphery of the power disk.
9. The piston apparatus according to claim 5 wherein the valve actuating means comprises a cam supported for rotation with the power disk and cam followers supported for actuation by the cam and operatively connected to the valve means.
10. An engine comprising:
11. An engine comprising:
12. The engine according to claim 11 further characterized by valve means in both ends of each of the cylinders for controlling the flow of fluid into and out of the cylinders, and means driven by the power disks for operating the valve means in synchronism with the reciprocation of the pistons.
13. The engine according to claim 12 wherein the valve means functions to control the flow of pressurized fluid into both ends of all three cylinders and to control the exhaust of spent fluid from the cylinders.
14. The engine according to claim 11 further including drive means operatively connected to the power disks for actuation thereby and forming the output of the engine.
15. The engine according to claim 11 wherein each of the cylinders is further characterized by at least one slot facing in the direction of the adjacent cylinder and wherein the crankpins of the crankshafts extend through the slots in the cylinders.
16. The engine according to claim 15 further including bearing means rotatably supporting the crankshaft member in the power disks and bearing means rotatably connecting the crankpins to the pistons.
17. A piston apparatus including:
1. A piston apparatus comprising:
2. The piston apparatus according to claim 1 further comprising valve means at each end of each cylinder and means driven by the power disk for operating the valve means in coordination with the reciprocation of the valve means.
3. The piston apparatus according to claim 2 wherein the valve means function to alternately admit pressurized fluid to and to exhaust spent fluid from both ends of both pistons, and further including drive means operatively connected to the power disk for actuation thereby.
4. The piston apparatus according to claim 3 wherein the drive means is further characterized by a series of teeth positioned at substantially equally spaced intervals around the periphery of the power disk and forming the output of the piston apparatus.
5. A piston apparatus comprising:
6. The piston apparatus according to claim 5 wherein the valve means functions to control the flow of pressurized fluid into and the exhaust of spent fluid from both ends of both pistons.
7. The piston apparatus according to claim 5 further including drive means operatively connected to the power disk for actuation thereby.
8. The piston apparatus according to claim 5 further characterized by a series of drive teeth positioned at equally spaced intervals around the entire periphery of the power disk.
9. The piston apparatus according to claim 5 wherein the valve actuating means comprises a cam supported for rotation with the power disk and cam followers supported for actuation by the cam and operatively connected to the valve means.
10. An engine comprising:
11. An engine comprising:
12. The engine according to claim 11 further characterized by valve means in both ends of each of the cylinders for controlling the flow of fluid into and out of the cylinders, and means driven by the power disks for operating the valve means in synchronism with the reciprocation of the pistons.
13. The engine according to claim 12 wherein the valve means functions to control the flow of pressurized fluid into both ends of all three cylinders and to control the exhaust of spent fluid from the cylinders.
14. The engine according to claim 11 further including drive means operatively connected to the power disks for actuation thereby and forming the output of the engine.
15. The engine according to claim 11 wherein each of the cylinders is further characterized by at least one slot facing in the direction of the adjacent cylinder and wherein the crankpins of the crankshafts extend through the slots in the cylinders.
16. The engine according to claim 15 further including bearing means rotatably supporting the crankshaft member in the power disks and bearing means rotatably connecting the crankpins to the pistons.
17. A piston apparatus including:
Description:
BACKGROUND AND SUMMARY OF THE INVENTION
This invention relates to a piston apparatus, and more particularly to a piston apparatus in which at least two double-ended pistons supported for reciprocation along perpendicular axes operate in conjunction with one or more power disks situated between the pistons for rotation about a third mutually perpendicular axis.
At the present time most piston mechanisms comprise one or more single-ended pistons each operating in a single-ended cylinder and each connected to a rotating crankshaft by means of an elongated connecting rod. For example, typical piston mechanisms of this type include carburation-ignition cycle engines of all sizes, diesel cycle engines, external combustion engines of various types, pumps, compressors, etc. It is true that piston mechanisms incorporating double-ended pistons operating in double-ended cylinders have been provided heretofore, particularly steam engines for use in locomotives, ships and similar applications. However, the only piston mechanisms incorporating double-ended pistons which have achieved even limited acceptance in the commercial market have been very large devices which are not practical for use in such applications as automobiles, light trucks, etc.
The present invention relates to a novel piston apparatus of the double-ended piston variety which is practical for use in relatively small engines, pumps, etc., and which otherwise achieves numerous advantages over the prior art. In accordance with the broader aspects of the invention, two double-ended pistons are mounted in double-ended cylinders for reciprocation along angularly offset axes. A power disk is mounted between the pistons for rotation about a third axis extending perpendicular to the axes of reciprocation of the pistons. A crankshaft is mounted in the power disk for rotation about an eccentric axis extending parallel to but offset from the third axis. The crankshaft includes a pair of crankpins each extending into one of the cylinders and rotatably connected to the double-ended piston therein.
In accordance with more specific aspects of the invention, the double-ended cylinders are each centered with respect to the third axis, and the axes of reciprocation of the doubleended pistons are perpendicular. Valve means are provided at both ends of each cylinder for controlling fluid flow into and out of the cylinder. The periphery of the power disk comprises a gear or a sprocket and thus serves as the power output in the case of an engine, etc. and as the power input in the case of a pump, etc.
Although the basic configuration of the piston apparatus comprises two double-ended pistons and a single power disk positioned therebetween, the invention is equally adapted for use in applications requiring three or more double-ended pistons. In such instances, at least the center double-ended piston is connected to crankpins extending from crankshafts mounted in power disks positioned on both sides of the piston. In the case of multiple piston applications of the invention, several power disks may be drivingly connected to a drive shaft mounted for rotation about an axis extending parallel to the axis of rotation of the power disks and serving either as the power input or as the power output for the apparatus.
DESCRIPTION OF THE DRAWINGS
A more complete understanding of the invention may be had by referring to the following Detailed Description when taken in conjunction with the accompanying Drawings, wherein:
FIG. 1 is a diagrammatic illustration of a piston apparatus incorporating the invention;
FIGS. 2a- 2h, inclusive, are illustrations of progressive steps in the operation of the piston apparatus shown in FIG. 1;
FIG. 3 is an illustration of a two cylinder piston apparatus incorporating the invention in which certain parts have been broken away more clearly to illustrate certain features of the invention;
FIG. 4 is an illustration of an alternative valving arrangement which may be utilized in the practice of the invention;
FIG. 5 is a perspective view of a three cylinder piston apparatus incorporating the invention;
FIG. 6 is an enlarged illustration of the three cylinder piston apparatus in which certain parts have been broken away more clearly to illustrate certain features of the invention;
FIG. 7 is an illustration of a three cylinder piston apparatus operating as a component part of an external combustion engine; and
FIG. 8 is a perspective view of a multiple cylinder piston apparatus incorporating the invention.
DETAILED DESCRIPTION
Referring now to the Drawings, and particularly to FIG. 1 thereof, a piston apparatus 10 incorporating the invention is diagrammatically illustrated. The piston apparatus 10 includes a first double-ended cylinder 12 having an axis 14 and a second double-ended cylinder 16 having an axis 18 which extends perpendicularly to the axis 14. The double-ended cylinders 12 and 16 are each centered about a third axis 20 extending mutually perpendicularly with respect to the axes 14 and 18.
A double-ended piston 22 is mounted for reciprocation in the double-ended cylinder 12 and a double-ended piston 26 is mounted for reciprocation in the double-ended cylinder 16. A power disk 28 is positioned between the cylinders 12 and 16 for rotation about the third axis 20. The power disk 28 has a cylindrical crankshaft receiving aperture 30 formed therein.
A crankshaft 32 is mounted in the power disk 28 for rotation about an eccentric axis 34 extending parallel to but offset from the third axis 20. The crankshaft 32 comprises a cylindrical portion 36 which is rotatably mounted in the crankshaft receiving aperture of the power disk 28. A pair of crankpins 38 and 40 extend in opposite directions from the cylindrical portion 36 of the crankshaft 32. The crankpin 38 is rotatably received in the piston 22 and the crankpin 40 is rotatably received in the piston 26.
Those skilled in the art will appreciate the fact that the piston apparatus 10 is adapted for operation in accordance with various operating modes. For example, if power is supplied to the piston apparatus 10 from an external prime mover drivingly connected to the power disk 28, the piston apparatus 10 may be operated as a pump, etc. On the other hand, if pressurized fluid is alternatively admitted to the opposite ends of the double-ended cylinders 12 and 16, the piston apparatus may be operated as an external combustion engine, etc. Finally, the piston apparatus 10 may be operated as an internal combustion engine, either by means of the carburation-ignition cycle commonly employed in automotive engines or by means of the Diesel cycle.
The operation of the piston apparatus 10 will be better understood by referring to FIGS. 2a-2h. In FIG. 2a the double-ended piston 22 is at the midpoint of its stroke and the double-ended piston 26 is at the upper end of its stroke. In FIG. 2b the piston 22 has moved rightwardly and the piston 26 has moved downwardly. This action causes a concurrent rotation of the power disk 28 through 45°.
In FIG. 2c the piston 22 is at the right-hand end of its stroke and the piston 26 is at the midpoint of its downward stroke. Concurrently the power disk 28 has rotated another 45°, thus completing one-quarter of a revolution. In FIG. 2d the piston 22 has begun its leftward reciprocation and the piston 26 has moved further downwardly. Concurrently the power disk 28 has rotated through another 45°.
In FIG. 2e, the piston 22 is at the midpoint of its leftward reciprocation and the piston 26 is at the bottom of its reciprocation. The power disk 28 has concurrently rotated through another 45°, thus completing one-half of a revolution. In FIG. 2f the leftward reciprocation of the piston 22 has continued and the piston 26 has begun its upward reciprocation. Concurrently the power disk 28 has rotated through another 45°.
In FIG. 2g the piston 22 is at the left-hand end of its reciprocation and the piston 26 is at the midpoint of its upward reciprocation. The power disk 28 has rotated through another 45°, thus completing three-quarters of a revolution. In FIG. 2h the piston 22 has begun its rightward reciprocation, upward reciprocation of the piston 26 has continued, and the power disk 24 has rotated through another 45° interval. On further movement of the pistons 22 and 26 rightwardly and upwardly, respectively, the component parts of the piston apparatus 10 are returned to the positions illustrated in FIG. 2a, at which point the power disk 28 has completed a full revolution.
Referring to FIG. 3, there is shown a two cylinder piston apparatus 50 incorporating the invention. The apparatus 50 includes a housing or block 52 formed from a conventional material such as cast iron, aluminum, etc. The block 52 defines a double-ended cylinder 54 having an axis 56 and a double-ended cylinder 58 having an axis 60. The axes 56 and 60 extend perpendicularly with respect to each other and mutually perpendicularly with respect to a third axis 62. The cylinders 54 and 58 are each centrally positioned with respect to the third axis 62. The opposite ends of both of the cylinders 54 and 58 are closed by four cylinder head assemblies 64. A double-ended piston 66 is mounted for reciprocation in the cylinder 54 and a double-ended piston 68 is mounted for reciprocation in the cylinder 58. Conventional piston rings 70 are provided at both ends of the pistons 66 and 68.
A power disk 72 is rotatably supported in the block 52 by means of a plurality of bearings 74. The bearings 74 support the power disk 72 for rotation about the third axis 62. A series of teeth 76 are positioned at equally spaced points around the periphery of the power disk 72 to define either the power input or the power output of the apparatus 50. In the particular embodiment of the invention illustrated in FIG. 3, the teeth 76 define a sprocket, and a chain 78 is engaged with the sprocket for use in transferring power with respect to the apparatus 50. It will be understood, however, that the teeth 76 may also define a gear, in which case a suitable gearset is utilized in transferring power.
A crankshaft 80 is rotatably supported in the power disk 72 by means of a plurality of bearings 82. The bearings 82 support the crankshaft 80 for rotation about an eccentric axis 84 extending parallel to but spaced apart from the third axis 62. A pair of crankpins 86 and 88 project outwardly from the opposite sides of the crankshaft 80. The crankpins 86 and 88 extend through slots 90 formed in the block 52 and through cylindrical passageways 92 formed in the pistons 66 and 68. The crankpins 86 and 88 are rotatably secured to the pistons 66 and 68 by means of a plurality of bearings 94.
An important feature of the invention comprises the relationship of the ends of the slots 90 to the positioning of the pistons 66 and 68 at the opposite ends of their respective strokes. Thus, as is clearly shown in FIG. 3, both the upper end of the piston 66 and the adjacent piston rings 70 are positioned well above the upper end of the slot 90 of the cylinder 54 when the piston 66 is at the bottom if its stroke. It will thus be understood that during the operation of the piston apparatus 50 there is no fluid or pressure loss through the slot 90 regardless of the positioning of the pistons 66 and 68 in the cylinders 54 and 58.
Each cylinder head assembly 64 of the piston apparatus 50 comprises valving apparatus 96 which functions to control fluid flow into and out of one end of one of the cylinders of the engine. The valving apparatus 96 illustrated in FIG. 3 comprises a cylindrical valve 98 having a pair of fluid passageways 100 and 102 formed therethrough, said passageways being both axially and angularly offset with respect to each other. Thus, whenever the cylindrical valve 98 is positioned as shown in full lines in FIG. 3, the passageway 100 interconnects a fitting 104 with a fluid passageway 106 extending to the upper end of the cylinder 54. On the other hand, whenever the valve 98 is in the dotted line position, the passageway 102 interconnects a similar fitting and a similar fluid passageway.
The positioning of the valve 98 and therefore the flow of fluid into and out of the cylinders 54 and 56 is controlled by a pair of camming surfaces 108 comprising part of the exterior periphery of the power disk 72. In the particular embodiment of the invention illustrated in FIG. 3, the cam 108 on the left-hand side of the power disk 72 operates the valving apparatus 96 in both ends of the cylinder 54, and the cam 108 on the right-hand side of the power disk 72 operates the valving apparatus 96 at the opposite ends of the cylinder 58. It will be understood, however, that a separate cam for each end of each cylinder may be provided if required by particular circumstances. The valves 98 and the cams 108 are interconnected by conventional cam followers 110, and each valve 98 is lightly spring-loaded so as to remain in engagement with its respective cam follower 110.
The piston apparatus 50 illustrated in FIG. 3 may comprise an external combustion engine, i.e., reciprocation of the pistons 66 and 68 and concurrent rotation of the power disk 72 is effected under the action of pressurized fluid supplied from an external source. In such cases the valves 98 typically remain in the position illustrated in full lines in FIG. 3 throughout one-half of each reciprocation of their respective piston and are moved to the position illustrated in dashed lines throughout the other half of the reciprocation of the piston. The valves 98 are operated similarly when the piston apparatus is utilized as a pump. It will be understood, however, that in some situations, and particularly in the case of an internal combustion engine, other valving arrangements will be required. Also, conventional apparatus may be utilized to permit varying of the timing of the operation of the valving apparatus 96 at each end of each cylinder.
In FIG. 4, there is shown an alternative valving mechanism 112 which may be utilized in the apparatus 50, it being understood that various valving arrangements in addition to those illustrated in FIGS. 3 and 4 may be utilized in the practice of the invention. The valving apparatus 112 comprises a pinion 114 rotatably supported on a shaft 116 and having an arm 118 which engages the cam follower 110. The pinion 114 is lightly spring loaded so that the arm 118 remains in engagement with the cam follower.
The pinion 114 of the valving apparatus 112 is mounted in mesh with a rack 120 which is connected to a sliding valving member 122. Depending upon the rotational positioning of the cam 108, the sliding valving member 122 serves either to connect a fitting 124 to a passageway 126 or to connect a fitting 128 to a passageway 130. In this manner the valving apparatus 112 functions identically to the valving apparatus 96 to control fluid flow into and out of one end of one of the cylinders comprising the apparatus 50.
In FIGS. 5 and 6 there is shown a three cylinder piston apparatus 132 incorporating the invention. Upon careful study, it will be understood that the three cylinder piston apparatus 132 comprises component parts which are substantially identical in construction and operation to the component parts of the two cylinder piston apparatus 50 illustrated in FIG. 3. For this reason the same reference numerals are utilized in FIG. 3 and in FIGS. 5 and 6 to designate the same or similar parts. Moreover, those component parts which have been added to the component parts of the two cylinder apparatus 50 in order to form the three cylinder apparatus 132 are designated in FIGS. 5 and 6 by means of a prime (').
Referring particularly to FIG. 6, one difference between the two cylinder apparatus 50 and the three cylinder apparatus 132 relates to the fact that the piston 66 is connected both to the power disk 72 and to the power disk 72'. This is accomplished by means of a crankpin 86 connected both to the crankshaft 80 mounted in the power disk 72 and to the crankshaft 80' mounted in the power disk 72'. Those skilled in the art will appreciate the fact that the crankpin 86 may be replaced by two crankpins extending from the crankshafts 80 and 80' and each rotatably connected to the piston 66, if desired.
As will be best understood by reference to FIG. 5, the three cylinder apparatus 132 is believed to be particularly adapted for use in motorcycles and similar applications. Thus, the block 52 of the apparatus 132 may be supported between the frame components of the motorcycle in the manner of a typical motorcycle engine, suitable brackets 52' being provided for this purpose. When the apparatus 132 is so positioned, the drive chains 78 and 78' are adapted to pass on opposite sides of the frame of the motorcycle and around sprockets secured to the opposite sides of the rear wheel. By this means both the drive torque and the tension of the drive chains are applied equally to both sides of the rear wheel.
Referring now to FIG. 7, a three cylinder piston apparatus 140 constructed substantially as shown in FIGS. 5 and 6 is utilized in an internal combustion engine 142. A suitable working fluid, for example "FREON," is stored in a reservoir 144. A plurality of storage batteries 146 are connected in series, and are utilized to drive both a pump 148 and an electrically powered heater 150. The pump 148 functions to withdraw working fluid from the reservoir 144 and to force the working fluid through the heater 150.
Heated working fluid from the heater 150 is directed through a series of lines 152 to the opposite ends of the three cylinders comprising the piston apparatus 140 and is selectively admitted thereto by means of suitable valving apparatus such as that shown in FIGS. 3 and 4. Spent working fluid is directed from the piston apparatus 140 to a manifold 154 through a plurality of lines 156. The working fluid passes through a condenser 158 and is then returned to the reservoir 144. Conventional circuitry 160 is utilized to recharge the storage batteries 146 on a periodic basis.
Those skilled in the art will appreciate the fact that the external combustion engine 142 illustrated in FIG. 7 is representative only, and that various modifications can be made in the design of the engine in order to suit particular requirements. Perhaps most importantly, the heater 150 of the engine 142 need not be electrically powered, but may instead use various conventional fuels in order to heat the working fluid. Typical fuels which may be utilized in the operation of the engine 142 include gasoline, fuel, oil, etc., depending on the particular heater design chosen for use in the engine.
In FIG. 8, there is shown a multiple cylinder piston apparatus 162 incorporating the invention. The apparatus 162 includes a block 164 having a plurality of double-ended cylinders formed therein with the axes of adjacent cylinders extending perpendicularly. A double-ended piston is mounted for reciprocation within each cylinder, and power disks are mounted within the engine block 165 for rotation about an axis extending perpendicularly to the axis of the cylinders. Each power disk is connected to the adjacent pistons by means of a crankshaft in the manner illustrated in FIG. 1.
One difference between the multiple cylinder apparatus 162 and the two and three cylinder devices illustrated in FIGS. 3 and 6 relates to the fact that the teeth formed on the periphery of each power disk in the apparatus 162 comprise gear teeth. The engine 162 is provided with a plurality of gears 166 each mounted in mesh with the gear teeth of one of the power disks. The gears 166 are in turn mounted in mesh with a plurality of gears 168 secured to a drive shaft 170. The drive shaft 170 is mounted for rotation about an axis extending parallel to the axis of rotation of the power disks of the apparatus 162.
It will be understood that in the case of an engine, the drive shaft 170 comprises the power output of the apparatus. For example, if such an engine is utilized in a vehicle, the drive shaft 170 could be connected through a conventional transmission and a differential to the drive wheels of the vehicle. On the other hand, in the case of a pump or a compressor, the drive shaft 170 would be connected to an external prime mover such as an electric motor or a conventional internal engine and would serve as the power input to the apparatus.
From the foregoing, it will be understood that the present invention comprises a novel piston apparatus incorporating numerous advantages over the prior art. An important feature of the invention relates to the fact that piston apparatus incorporating the invention are adapted for fabrication from a small number of relatively uncomplicated parts and are therefore economical to manufacture and use. Another important feature of the invention relates to the fact that piston apparatus incorporating substantially the same design may be utilized as internal combustion engines, as external combustion engines, or as pumps, compressors, etc. Still another important feature of the invention relates to the fact that by means of the invention a double-ended piston apparatus may be manufactured in relatively small sizes, and is therefore adapted for use in automobiles, light trucks, motorcycles, and similar applications. Yet another advantage to the use of the invention involves the fact that engines constructed in accordance therewith are characterized by very high stall torque. Finally, the use of the invention is advantageous in that external combustion engines employing the invention operate at very high efficiency at low RPM's.
Although particular embodiments of the invention have been illustrated in the accompanying Drawings and described in the foregoing Detailed Description, it will be understood that the invention is not limited to the embodiments disclosed, but is capable of numerous rearrangements, modifications, and substitutions of parts and elements without departing from the spirit of the invention.
This invention relates to a piston apparatus, and more particularly to a piston apparatus in which at least two double-ended pistons supported for reciprocation along perpendicular axes operate in conjunction with one or more power disks situated between the pistons for rotation about a third mutually perpendicular axis.
At the present time most piston mechanisms comprise one or more single-ended pistons each operating in a single-ended cylinder and each connected to a rotating crankshaft by means of an elongated connecting rod. For example, typical piston mechanisms of this type include carburation-ignition cycle engines of all sizes, diesel cycle engines, external combustion engines of various types, pumps, compressors, etc. It is true that piston mechanisms incorporating double-ended pistons operating in double-ended cylinders have been provided heretofore, particularly steam engines for use in locomotives, ships and similar applications. However, the only piston mechanisms incorporating double-ended pistons which have achieved even limited acceptance in the commercial market have been very large devices which are not practical for use in such applications as automobiles, light trucks, etc.
The present invention relates to a novel piston apparatus of the double-ended piston variety which is practical for use in relatively small engines, pumps, etc., and which otherwise achieves numerous advantages over the prior art. In accordance with the broader aspects of the invention, two double-ended pistons are mounted in double-ended cylinders for reciprocation along angularly offset axes. A power disk is mounted between the pistons for rotation about a third axis extending perpendicular to the axes of reciprocation of the pistons. A crankshaft is mounted in the power disk for rotation about an eccentric axis extending parallel to but offset from the third axis. The crankshaft includes a pair of crankpins each extending into one of the cylinders and rotatably connected to the double-ended piston therein.
In accordance with more specific aspects of the invention, the double-ended cylinders are each centered with respect to the third axis, and the axes of reciprocation of the doubleended pistons are perpendicular. Valve means are provided at both ends of each cylinder for controlling fluid flow into and out of the cylinder. The periphery of the power disk comprises a gear or a sprocket and thus serves as the power output in the case of an engine, etc. and as the power input in the case of a pump, etc.
Although the basic configuration of the piston apparatus comprises two double-ended pistons and a single power disk positioned therebetween, the invention is equally adapted for use in applications requiring three or more double-ended pistons. In such instances, at least the center double-ended piston is connected to crankpins extending from crankshafts mounted in power disks positioned on both sides of the piston. In the case of multiple piston applications of the invention, several power disks may be drivingly connected to a drive shaft mounted for rotation about an axis extending parallel to the axis of rotation of the power disks and serving either as the power input or as the power output for the apparatus.
DESCRIPTION OF THE DRAWINGS
A more complete understanding of the invention may be had by referring to the following Detailed Description when taken in conjunction with the accompanying Drawings, wherein:
FIG. 1 is a diagrammatic illustration of a piston apparatus incorporating the invention;
FIGS. 2a- 2h, inclusive, are illustrations of progressive steps in the operation of the piston apparatus shown in FIG. 1;
FIG. 3 is an illustration of a two cylinder piston apparatus incorporating the invention in which certain parts have been broken away more clearly to illustrate certain features of the invention;
FIG. 4 is an illustration of an alternative valving arrangement which may be utilized in the practice of the invention;
FIG. 5 is a perspective view of a three cylinder piston apparatus incorporating the invention;
FIG. 6 is an enlarged illustration of the three cylinder piston apparatus in which certain parts have been broken away more clearly to illustrate certain features of the invention;
FIG. 7 is an illustration of a three cylinder piston apparatus operating as a component part of an external combustion engine; and
FIG. 8 is a perspective view of a multiple cylinder piston apparatus incorporating the invention.
DETAILED DESCRIPTION
Referring now to the Drawings, and particularly to FIG. 1 thereof, a piston apparatus 10 incorporating the invention is diagrammatically illustrated. The piston apparatus 10 includes a first double-ended cylinder 12 having an axis 14 and a second double-ended cylinder 16 having an axis 18 which extends perpendicularly to the axis 14. The double-ended cylinders 12 and 16 are each centered about a third axis 20 extending mutually perpendicularly with respect to the axes 14 and 18.
A double-ended piston 22 is mounted for reciprocation in the double-ended cylinder 12 and a double-ended piston 26 is mounted for reciprocation in the double-ended cylinder 16. A power disk 28 is positioned between the cylinders 12 and 16 for rotation about the third axis 20. The power disk 28 has a cylindrical crankshaft receiving aperture 30 formed therein.
A crankshaft 32 is mounted in the power disk 28 for rotation about an eccentric axis 34 extending parallel to but offset from the third axis 20. The crankshaft 32 comprises a cylindrical portion 36 which is rotatably mounted in the crankshaft receiving aperture of the power disk 28. A pair of crankpins 38 and 40 extend in opposite directions from the cylindrical portion 36 of the crankshaft 32. The crankpin 38 is rotatably received in the piston 22 and the crankpin 40 is rotatably received in the piston 26.
Those skilled in the art will appreciate the fact that the piston apparatus 10 is adapted for operation in accordance with various operating modes. For example, if power is supplied to the piston apparatus 10 from an external prime mover drivingly connected to the power disk 28, the piston apparatus 10 may be operated as a pump, etc. On the other hand, if pressurized fluid is alternatively admitted to the opposite ends of the double-ended cylinders 12 and 16, the piston apparatus may be operated as an external combustion engine, etc. Finally, the piston apparatus 10 may be operated as an internal combustion engine, either by means of the carburation-ignition cycle commonly employed in automotive engines or by means of the Diesel cycle.
The operation of the piston apparatus 10 will be better understood by referring to FIGS. 2a-2h. In FIG. 2a the double-ended piston 22 is at the midpoint of its stroke and the double-ended piston 26 is at the upper end of its stroke. In FIG. 2b the piston 22 has moved rightwardly and the piston 26 has moved downwardly. This action causes a concurrent rotation of the power disk 28 through 45°.
In FIG. 2c the piston 22 is at the right-hand end of its stroke and the piston 26 is at the midpoint of its downward stroke. Concurrently the power disk 28 has rotated another 45°, thus completing one-quarter of a revolution. In FIG. 2d the piston 22 has begun its leftward reciprocation and the piston 26 has moved further downwardly. Concurrently the power disk 28 has rotated through another 45°.
In FIG. 2e, the piston 22 is at the midpoint of its leftward reciprocation and the piston 26 is at the bottom of its reciprocation. The power disk 28 has concurrently rotated through another 45°, thus completing one-half of a revolution. In FIG. 2f the leftward reciprocation of the piston 22 has continued and the piston 26 has begun its upward reciprocation. Concurrently the power disk 28 has rotated through another 45°.
In FIG. 2g the piston 22 is at the left-hand end of its reciprocation and the piston 26 is at the midpoint of its upward reciprocation. The power disk 28 has rotated through another 45°, thus completing three-quarters of a revolution. In FIG. 2h the piston 22 has begun its rightward reciprocation, upward reciprocation of the piston 26 has continued, and the power disk 24 has rotated through another 45° interval. On further movement of the pistons 22 and 26 rightwardly and upwardly, respectively, the component parts of the piston apparatus 10 are returned to the positions illustrated in FIG. 2a, at which point the power disk 28 has completed a full revolution.
Referring to FIG. 3, there is shown a two cylinder piston apparatus 50 incorporating the invention. The apparatus 50 includes a housing or block 52 formed from a conventional material such as cast iron, aluminum, etc. The block 52 defines a double-ended cylinder 54 having an axis 56 and a double-ended cylinder 58 having an axis 60. The axes 56 and 60 extend perpendicularly with respect to each other and mutually perpendicularly with respect to a third axis 62. The cylinders 54 and 58 are each centrally positioned with respect to the third axis 62. The opposite ends of both of the cylinders 54 and 58 are closed by four cylinder head assemblies 64. A double-ended piston 66 is mounted for reciprocation in the cylinder 54 and a double-ended piston 68 is mounted for reciprocation in the cylinder 58. Conventional piston rings 70 are provided at both ends of the pistons 66 and 68.
A power disk 72 is rotatably supported in the block 52 by means of a plurality of bearings 74. The bearings 74 support the power disk 72 for rotation about the third axis 62. A series of teeth 76 are positioned at equally spaced points around the periphery of the power disk 72 to define either the power input or the power output of the apparatus 50. In the particular embodiment of the invention illustrated in FIG. 3, the teeth 76 define a sprocket, and a chain 78 is engaged with the sprocket for use in transferring power with respect to the apparatus 50. It will be understood, however, that the teeth 76 may also define a gear, in which case a suitable gearset is utilized in transferring power.
A crankshaft 80 is rotatably supported in the power disk 72 by means of a plurality of bearings 82. The bearings 82 support the crankshaft 80 for rotation about an eccentric axis 84 extending parallel to but spaced apart from the third axis 62. A pair of crankpins 86 and 88 project outwardly from the opposite sides of the crankshaft 80. The crankpins 86 and 88 extend through slots 90 formed in the block 52 and through cylindrical passageways 92 formed in the pistons 66 and 68. The crankpins 86 and 88 are rotatably secured to the pistons 66 and 68 by means of a plurality of bearings 94.
An important feature of the invention comprises the relationship of the ends of the slots 90 to the positioning of the pistons 66 and 68 at the opposite ends of their respective strokes. Thus, as is clearly shown in FIG. 3, both the upper end of the piston 66 and the adjacent piston rings 70 are positioned well above the upper end of the slot 90 of the cylinder 54 when the piston 66 is at the bottom if its stroke. It will thus be understood that during the operation of the piston apparatus 50 there is no fluid or pressure loss through the slot 90 regardless of the positioning of the pistons 66 and 68 in the cylinders 54 and 58.
Each cylinder head assembly 64 of the piston apparatus 50 comprises valving apparatus 96 which functions to control fluid flow into and out of one end of one of the cylinders of the engine. The valving apparatus 96 illustrated in FIG. 3 comprises a cylindrical valve 98 having a pair of fluid passageways 100 and 102 formed therethrough, said passageways being both axially and angularly offset with respect to each other. Thus, whenever the cylindrical valve 98 is positioned as shown in full lines in FIG. 3, the passageway 100 interconnects a fitting 104 with a fluid passageway 106 extending to the upper end of the cylinder 54. On the other hand, whenever the valve 98 is in the dotted line position, the passageway 102 interconnects a similar fitting and a similar fluid passageway.
The positioning of the valve 98 and therefore the flow of fluid into and out of the cylinders 54 and 56 is controlled by a pair of camming surfaces 108 comprising part of the exterior periphery of the power disk 72. In the particular embodiment of the invention illustrated in FIG. 3, the cam 108 on the left-hand side of the power disk 72 operates the valving apparatus 96 in both ends of the cylinder 54, and the cam 108 on the right-hand side of the power disk 72 operates the valving apparatus 96 at the opposite ends of the cylinder 58. It will be understood, however, that a separate cam for each end of each cylinder may be provided if required by particular circumstances. The valves 98 and the cams 108 are interconnected by conventional cam followers 110, and each valve 98 is lightly spring-loaded so as to remain in engagement with its respective cam follower 110.
The piston apparatus 50 illustrated in FIG. 3 may comprise an external combustion engine, i.e., reciprocation of the pistons 66 and 68 and concurrent rotation of the power disk 72 is effected under the action of pressurized fluid supplied from an external source. In such cases the valves 98 typically remain in the position illustrated in full lines in FIG. 3 throughout one-half of each reciprocation of their respective piston and are moved to the position illustrated in dashed lines throughout the other half of the reciprocation of the piston. The valves 98 are operated similarly when the piston apparatus is utilized as a pump. It will be understood, however, that in some situations, and particularly in the case of an internal combustion engine, other valving arrangements will be required. Also, conventional apparatus may be utilized to permit varying of the timing of the operation of the valving apparatus 96 at each end of each cylinder.
In FIG. 4, there is shown an alternative valving mechanism 112 which may be utilized in the apparatus 50, it being understood that various valving arrangements in addition to those illustrated in FIGS. 3 and 4 may be utilized in the practice of the invention. The valving apparatus 112 comprises a pinion 114 rotatably supported on a shaft 116 and having an arm 118 which engages the cam follower 110. The pinion 114 is lightly spring loaded so that the arm 118 remains in engagement with the cam follower.
The pinion 114 of the valving apparatus 112 is mounted in mesh with a rack 120 which is connected to a sliding valving member 122. Depending upon the rotational positioning of the cam 108, the sliding valving member 122 serves either to connect a fitting 124 to a passageway 126 or to connect a fitting 128 to a passageway 130. In this manner the valving apparatus 112 functions identically to the valving apparatus 96 to control fluid flow into and out of one end of one of the cylinders comprising the apparatus 50.
In FIGS. 5 and 6 there is shown a three cylinder piston apparatus 132 incorporating the invention. Upon careful study, it will be understood that the three cylinder piston apparatus 132 comprises component parts which are substantially identical in construction and operation to the component parts of the two cylinder piston apparatus 50 illustrated in FIG. 3. For this reason the same reference numerals are utilized in FIG. 3 and in FIGS. 5 and 6 to designate the same or similar parts. Moreover, those component parts which have been added to the component parts of the two cylinder apparatus 50 in order to form the three cylinder apparatus 132 are designated in FIGS. 5 and 6 by means of a prime (').
Referring particularly to FIG. 6, one difference between the two cylinder apparatus 50 and the three cylinder apparatus 132 relates to the fact that the piston 66 is connected both to the power disk 72 and to the power disk 72'. This is accomplished by means of a crankpin 86 connected both to the crankshaft 80 mounted in the power disk 72 and to the crankshaft 80' mounted in the power disk 72'. Those skilled in the art will appreciate the fact that the crankpin 86 may be replaced by two crankpins extending from the crankshafts 80 and 80' and each rotatably connected to the piston 66, if desired.
As will be best understood by reference to FIG. 5, the three cylinder apparatus 132 is believed to be particularly adapted for use in motorcycles and similar applications. Thus, the block 52 of the apparatus 132 may be supported between the frame components of the motorcycle in the manner of a typical motorcycle engine, suitable brackets 52' being provided for this purpose. When the apparatus 132 is so positioned, the drive chains 78 and 78' are adapted to pass on opposite sides of the frame of the motorcycle and around sprockets secured to the opposite sides of the rear wheel. By this means both the drive torque and the tension of the drive chains are applied equally to both sides of the rear wheel.
Referring now to FIG. 7, a three cylinder piston apparatus 140 constructed substantially as shown in FIGS. 5 and 6 is utilized in an internal combustion engine 142. A suitable working fluid, for example "FREON," is stored in a reservoir 144. A plurality of storage batteries 146 are connected in series, and are utilized to drive both a pump 148 and an electrically powered heater 150. The pump 148 functions to withdraw working fluid from the reservoir 144 and to force the working fluid through the heater 150.
Heated working fluid from the heater 150 is directed through a series of lines 152 to the opposite ends of the three cylinders comprising the piston apparatus 140 and is selectively admitted thereto by means of suitable valving apparatus such as that shown in FIGS. 3 and 4. Spent working fluid is directed from the piston apparatus 140 to a manifold 154 through a plurality of lines 156. The working fluid passes through a condenser 158 and is then returned to the reservoir 144. Conventional circuitry 160 is utilized to recharge the storage batteries 146 on a periodic basis.
Those skilled in the art will appreciate the fact that the external combustion engine 142 illustrated in FIG. 7 is representative only, and that various modifications can be made in the design of the engine in order to suit particular requirements. Perhaps most importantly, the heater 150 of the engine 142 need not be electrically powered, but may instead use various conventional fuels in order to heat the working fluid. Typical fuels which may be utilized in the operation of the engine 142 include gasoline, fuel, oil, etc., depending on the particular heater design chosen for use in the engine.
In FIG. 8, there is shown a multiple cylinder piston apparatus 162 incorporating the invention. The apparatus 162 includes a block 164 having a plurality of double-ended cylinders formed therein with the axes of adjacent cylinders extending perpendicularly. A double-ended piston is mounted for reciprocation within each cylinder, and power disks are mounted within the engine block 165 for rotation about an axis extending perpendicularly to the axis of the cylinders. Each power disk is connected to the adjacent pistons by means of a crankshaft in the manner illustrated in FIG. 1.
One difference between the multiple cylinder apparatus 162 and the two and three cylinder devices illustrated in FIGS. 3 and 6 relates to the fact that the teeth formed on the periphery of each power disk in the apparatus 162 comprise gear teeth. The engine 162 is provided with a plurality of gears 166 each mounted in mesh with the gear teeth of one of the power disks. The gears 166 are in turn mounted in mesh with a plurality of gears 168 secured to a drive shaft 170. The drive shaft 170 is mounted for rotation about an axis extending parallel to the axis of rotation of the power disks of the apparatus 162.
It will be understood that in the case of an engine, the drive shaft 170 comprises the power output of the apparatus. For example, if such an engine is utilized in a vehicle, the drive shaft 170 could be connected through a conventional transmission and a differential to the drive wheels of the vehicle. On the other hand, in the case of a pump or a compressor, the drive shaft 170 would be connected to an external prime mover such as an electric motor or a conventional internal engine and would serve as the power input to the apparatus.
From the foregoing, it will be understood that the present invention comprises a novel piston apparatus incorporating numerous advantages over the prior art. An important feature of the invention relates to the fact that piston apparatus incorporating the invention are adapted for fabrication from a small number of relatively uncomplicated parts and are therefore economical to manufacture and use. Another important feature of the invention relates to the fact that piston apparatus incorporating substantially the same design may be utilized as internal combustion engines, as external combustion engines, or as pumps, compressors, etc. Still another important feature of the invention relates to the fact that by means of the invention a double-ended piston apparatus may be manufactured in relatively small sizes, and is therefore adapted for use in automobiles, light trucks, motorcycles, and similar applications. Yet another advantage to the use of the invention involves the fact that engines constructed in accordance therewith are characterized by very high stall torque. Finally, the use of the invention is advantageous in that external combustion engines employing the invention operate at very high efficiency at low RPM's.
Although particular embodiments of the invention have been illustrated in the accompanying Drawings and described in the foregoing Detailed Description, it will be understood that the invention is not limited to the embodiments disclosed, but is capable of numerous rearrangements, modifications, and substitutions of parts and elements without departing from the spirit of the invention.