US3554097A

US3554097A - Pressure engine

Info

Publication number: US3554097A
Application number: US801558A
Authority: US
Inventors: William Karpowicz
Original assignee: Individual
Current assignee: Individual
Priority date: 1969-02-24
Filing date: 1969-02-24
Publication date: 1971-01-12
Anticipated expiration: 1988-01-12

Abstract

This disclosure is directed to a pressure engine in which pressure developed in a cylinder and acting against a piston generates a unidirectional force component which is transmitted to an output shaft through a rack and pinion type gearing arrangement into a unidirectional rotative motion of the output shaft. Rotary valving provides positive intake and exhaust functions, and the engine is self-lubricating.

Description

United States Patent [72] lnventor William Karpowicz 230 W. 10th St.. New York, N.Y. 10025 [2 l] Appl. No. 801,558 [22] Filed Feb. 24, 1969 [45 Patented Jan. 12,197]

[54] PRESSURE ENGINE 10 Claims, 5 Drawing Figs.

[52] U.S. Cl 92/136 [51] I Int. CL... F0111 9/00 [50] Field of Search. 92/ l 36; 91/218, 413; 103/214 [56] References Cited UNITED STATES PATENTS 7l2,855 11/1902 Schmick 92/136X s s4 i at g; 4

3/1910 Poulson 92/130x 2,750,934 6/1956 Mag 92/135 3,444,784 5/1969 Wengerd 91/413 I Primary Examiner-Robert M. Walker Att0rneyMarn & Jangarathis ABSTRACT: This disclosure is directed to a pressure engine in which pressure developed in a cylinder and acting against a piston generates a unidirectional force component which is transmitted to an output shaft through a rack and pinion type gearing arrangement. A unidirectional clutch assembly translates alternating rotative motion from the rack and pinion gear arrangement into a unidirectional rotative motion of the output shaft. Rotary Valving provides positive intake and exhaust functions, and the 'engine is self-lubricating.

PRESSURE ENGINE BACKGROUND OF THE INVENTION Recent years have witnessed a rush of those concerned with the development of internal combustion and pressure engines to highly'sophisticated,delicately balanced, exceedingly complex engines such as turbines and high performance reciprocating and rotary engines. Therush to develop such sophisticated technology 'has caused a significant neglect in those areas of engine technology which are related to the more fundamental, less complicated engine apparatus.

Known reciprocating engines ordinarily utilize connecting rods and crank shafts to translate the reciprocating motion of the pistons to a rotary motion suitable as an output for driving other devices. The connecting rods, which connect the pistons with the throw portions of the crank shaft, are in alignment with the axes of reciprocation of the pistons only at the positions of piston Top Dead'Center (TDC) and Bottom Dead Center (BDC). At all other times, the axes of the connecting rods are misaligned with the axes of reciprocation of the piston, the misalignment being greatest substantially midway between the TDC and BDCpositions.

One effect of the misalignment of the connecting rods with the axes of reciprocation of the pistons is the generation of a force component directed through the pistons against the cylinder walls. This radially directed component causes friction and wear in the engine and therewith a loss of power and efficiency. An additional disadvantage of the misalignment is the variation in torque acting on the crank shaft. Thus, when any one of the pistons is at TDC, the axis of its connecting rod, the axis of rotation of the crank shaft and the axis of reciprocation of the piston are all aligned so that ho torque is generated atall. From this position the torque increases to a maximum at a position wherein the tie rod and throw are at maximum dislocation from the axisof rotation'of the crank shaft. Very obviously, any time maximum torque is not being exerted, power is being lost.

SUMMARY OF THE INVENTION It is the object of the present invention, therefore, to overcome the above-noted'disadvantages. More specifically, the present invention embodies an improved,fundamental, less delicate reciprocating engine which is highly reliable, inexpensive to manufacture, versatile in its range of possible power and speed outputs, and highly efficient as a result of the elimination of sources of power loss and wear.

It is preferred that the engine of the invention have from two to six cylinders. Pistons and connecting rods are in a manner which allows some play," and the straight line power stroke push is translated into rotational motion through a combination of rack and pinion gearing and a one-way clutch, eliminating all of the above-noted problems with crankshaft type engines. Valving preferably comprises a low power drain,

- snap acting rotary valve system, which both admits pressurized fluid and exhausts expended fluid through a single opening in the cylinder head. In addition, the snap turn feature provides instantaneous full alignment of port openings, a significant improvement on existing systems. In four or six cylinder embodiments it is possible to arrange the valving so that two cylinders can operate simultaneously, greatly increasing power output for a given size engine with the same measure of input pressure.

Means are provided to effect automatic lubrication of all working parts and also to dampen the (generally downward) thrust of reciprocating parts. A further feature of the present invention is that it can be manufactured entirely from readily available stock parts and materials, and requires no forgings or castings. It is thus well adapted for specialized, low-volume applications.

BRIEF DESCRIPTION OF THE DRAWINGS The exact nature of this invention and its attendant advantages will be better understood by a consideration of the following detailed description when read in light of the annexed drawings wherein:

FIG. 1 is a side elevational view of a pressure engine according to the present invention;

FIG. 2 is a cross-sectional view through the plane 2-2 of FIG. 1;

FIG. 3 is a cross-sectional view through the plane 33 of FIG. 2;

FIG. 4 is a partial cross-sectional elevational view, similar to the view of FIG. 2; and

FIG. 5 is a cross-sectional view through the plane 5-5 of FIG. 2.

DETAILED DESCRIPTION Referring initially to FIG. 1, there is shown a pressure engine according to the present invention and designated generally by the reference numeral 10. Engine comprises a main casing 12, four lower casing sections 14 suitably secured to the lower surface of main casing 12 through apertures 15 (FIG. 2) therethrough, and four block sections 16 each mounted vertically above one of the lower casing sections, and each being aligned to an opening 17 (FIG. 2) in the upper surface of the main casing 12. Each block section 16 cooperates with the aligned lower casing section 14 and the related portions of the main casing 12 to define a cylinder section 20, shown generally in FIG. 2. Thus it can be seen that the pressure engine 10 comprises four cylinder sections 20. It is to be recognized, however, that as many or as few cylinder sections as needed can be provided to construct a pressure engine of any desired size without departing from the scope of the present invention.

Referring to FIG. 2, there is shown a cross-sectional view through the plane 2-2 of FIG. 1 which view represents a typical cylinder section 20. In that each of the cylinder sections is identical, a description of the structure of the one shown may be taken as a description of the structure of each.

As noted before, each cylinder section 20 comprises a portion of main casing 12, a lower casing section 14 and a block section 16. Lower casing section 14 is generally cylindrical having one closed end 22 and an open end 23 which is adapted for receipt within the aperture 15 of the lower surface of main casing 12. Formed on lower casing section 14 adjacent open end 23 is an outwardly extending flange 24 which is adapted to abut the lower surface of main casing 12 and limit the amount of entry of lower casing section 14 into apertures 15. The central portion of lower casing section 14 defines a sump 25 for lubricating oil as will be discussed further in detail, hereinbelow.

Each block section 16 comprises a generally cylindrical body portion 27 having a lower flanged surface 28 and an upper surface 29 parallel to lower flanged surface 28. The interior of the block section 16 is cylindrical and of a diameter equal to the diameter of opening 17 in the upper wall of main casing 12. A sleeve 30 is rigidly received within block section 16 and extends longitudinally axially from upper surface 29 through the block section and beyond lower flanged surface 28 by an amount substantially equal to the thickness of the upper wall of main casing 12. Thus, to assemble block section 16 with respect to main casing 12, the body portion 27 is positioned and secured coaxially over opening 17 so that the lower portion of sleeve 30 is received within opening 17. The upper end of block section 16 is closed by a head 32 which is mounted on and suitable rigidly secured to body portion 27 at upper surface 29.

Mounted for reciprocating movement within sleeve 30 is a piston 33. The inner surface of sleeve 30, block head 32 and the upper surface of piston 33 cooperate to define a pressure chamber 31 into which pressurized gas is introduced to drive the piston, and from which spent gas is exhausted by the up ward movement of the piston. To the underside of the piston 33 is suitably fastened, such as by universal ball type connection 34, a connecting rod 35. Connecting rod 35 is an elongate hollow member having a valve actuating pawl 37 mounted adjacent its upper end, a valve repositioning return pin 370 at a lower point, and a yoke and pinion assembly 38 mounted at its lower end. Yoke and pinion assembly 38 comprises a forked yoke element 39 (FIG. 3) and a pinion 40.

Pinion 40, on its one side, engages a fixed rack 42 which is rigidly mounted within main casing 12. On its other side, pinion 40 engages a tubular double rack 44 which is slidably mounted for reciprocation on a guide rod 45. Double rack 44 has a first set of teeth 47 formed on one side thereof for operatively engaging the teeth of pinion 40, and a second set of teeth 48 formed on the side opposite the one side, the second set of teeth 48 being in operative engagement with a power gear 50. Thus, in the operation of pressure engine 10, as will be discussed in detail infra, as connecting rod 35 is displaced downwardly with piston 33, pinion 40 is caused to rotate as a result of its downward displacement and its operative engagement with fixed rack 42. The rotation of pinion 40 causes a downward displacement of tubular double rack 44 on guide rod 45, which, in turn, causes a rotation of power gear 50. An important feature of the invention is the fact that, if pinion 40 is displaced downwardly a distance d, double rack 44 will be displaced a distance 2d. The amount of output shaft rotation can thus be controlled by the size of power gear 50 and stroke length, and can conveniently be 220 or more. Further, power delivered is at the same level at the beginning, middle and end of a stroke, Le. a constance leverage factor is maintained. This is a significant advantage, when it is considered that the maximum torque-turn per stroke in a crankshaft is less than 180, and that power delivery to a crankshaft is nonuniform.

Guide rod 45 is a tubular member having a centrally disposed conduit 52 extending axially throughout its length. The lower end 53 of guide rod 45 is rigidly secured to the closed end 22 of lower casing section 14, and the upper end 54 of guide rod 45 extends upwardly within tubular double rack 44. A plurality of passages 55 extend radially outwardly from conduit 52 through the wall of guide rod 45 adjacent its lower end 53 to communicate conduit 52 with lubricant sump 25. Similarly, a plurality of passages 56 extend generally radially outwardly from conduit 52 through the walls of guide rod 45 adjacent its upper end 54. The purpose of

passages

55 and 56, and of conduit 52, is to provide for a circulation of lubricating oil from sump 25 to the working parts as will be discussed further infra.

A coil spring 58 is mounted around guide rod 45 and abuts, at its upper end, the lower surface of tubular double rack 44, and at its lower end, the closed end 22 of lower ca ng section 14. As tubular double rack 44 is moved downwardly by the action of pinion 40, coil spring 58 is compressed to progressively resist further downward movement. Thus, a downward power stroke by piston 33 is completed and the pressure above the piston is released, coil spring 58 urges the piston upwardly to its initial position to reposition the parts for the next power stroke.

As noted above, the teeth 48 of tubular double rack 44 operatively engage a power gear 50. Power gear 50 is mounted on a unidirectional clutch 62 which is in turn mounted on a rotatable load shaft 60. As is best seen in FIG. 3, shaft 60 extends longitudinally through main casing 12 and is rotatably mounted thereon by a plurality of bearings such as roller bearings 61, supported in moveable housing 61b. As can be seen in FIG. 1, mounted on one end of load shaft 60 is a fly wheel 63. The other end 64 of load shaft 60 is adapted to be attached to a load to be driven. Moveable bearing housings 61b and moveable shaft seal plates 610 can be adjusted to accommodate different sizes of power gear 50. In operation, when tubular double rack 44 is driven downwardly as a resvlt of the downward movement of piston 33 on power stroke, power gear 50 is causes to move in a counterclockwise direction as seen in FIG. 2. Counterclockwise rotation of power gear 50 causes unidirectional clutch 62 to engage thereby causing load shaft 60 to also rotate in the counterclockwise direction. Conversely, upon upward movement of piston 33, power gear 50 rotates in a clockwise direction as seen in FIGv 2, which rotation disengages clutch 62 thereby allowing continued counterclockwise rotation of load shaft 60.

Referring now to FIGS. 2, 4 and 5, the pressure engine of the present invention is provided with a valving system designated generally by the reference numeral 70. More specifically, the valving system comprises a common manifold 72 having four valving assemblies 73 (FIG. 5), one for each cylinder section 20, and two valve positioning assemblies 74, one at each end of common manifold 72.

As best seen in FIG. 5, common manifold 72 is rigidly mounted in lubricant impregnated sleeve bearing 76 of valving assembly 73. Concentrically mounted around sleeve bearing 76 is a gas passage sleeve 77, within which the sleeve bearing 76 and common manifold 72 rotate. Gas passage sleeve 77 is provided with an inlet opening 78 and an exhaust passage 79, both in communication with a passage 80 which extends from gas passage sleeve 77 through head 32 into chamber 31. A spring loaded ball-type check valve 81 is mounted to extend diametrically through sleeve bearing 76 and common manifold 72 from inlet opening 78 to a high pressure fluid supply conduit 82.

Also formed in common manifold 72 is an exhaust port 85 which extends through common manifold 72 and sleeve bearing 76 at a position which is alignable with exhaust passage 79. Thus, when common manifold 72 and sleeve bearing 76 are rotatable positioned to have exhaust port 85 in alignment with exhaust passage 79, gas from within chamber 31 can move or be driven upwardly through passage 80 into exhaust passage 79 and thereafter through exhaust port 85 into common manifold 72 to be discharged to atmosphere or otherwise through an exhaust line 86 (FIG. 2).

It can be recognized, therefore, that the common manifold 72 is repositioned for each piston stroke to provide alignment of the respective ports and passages as required for pressure inlet and gas exhaust. The repositioning is accomplished by intermittent rotation imparted to the common manifold 72 by pawl, arm and chain actuating linkage. As noted above, a valve-actuating pawl 37 is mounted on connecting rod 35 for movement therewith. Pivotally mounted, at one end, on fixed rack 42 is a valve arm 88 which is positioned to be engaged by pawl 37 as piston 33 completes a downward stroke. The engagement with pawl 37 causes valve arm 88 to rotate in a clockwise direction as seen in FIGS. 2 and 4. The other end of valve arm 88 comprises a ball 89 which cooperates with a valve rod 90 to define a ball joint 91. Valve rod 90 extends slidably through a bushing 92 mounted in an opening 93 in the upper wall of main casing 12. A resilient grommet 94 is mounted on valve rod 90 between ball joint 91 and bushing 92 to absorb the shock of operation of the actuating linkage, and to stop the piston-connecting rod mechanism at its proper operating position.

Attached to the top of valve rod 90 is an actuating chain 96 (FIG. 2) which extends upwardly to be wrapped around and connected to a unidirectional clutch 98 mounted on common manifold 72. Unidirectional clutch 98 is mounted on common manifold 72 so that downward movement of actuating chain 96 engages the clutch causing snap action rotation of the manifold and upward movement of the actuating chain 96 disengages the clutch allowing the chain to move freely with respect to common manifold 72. A helical return spring 99 is mounted concentrically around unidirectional clutch 98 and is positioned with one end attached to unidirectional clutch 98 and the other attached to the stationary gas passage sleeve 77. Thus, as actuating chain 96 moves downwardly to engage unidirectional clutch 98 and rotate common manifold 72, helical return spring 99 is coiled and loaded. Upon completion of the downward movement of actuating chain 96, helical return spring 99 urges unidirectional clutch 98 to rotate in the opposite direction thereby disengaging the clutch and causing the repositioning of actuating chain 96 to its initial wrap around position. Guide pin 37a moves, on the return stroke of connecting rod 35, against the underside of valve arm 88,

grommet 94 acting as a cushion. This permits spring 99 to uncoil,

From the above, it can be seen that proper intermittent rotational positioning of common manifold 72 is necessary to insure proper alignment of the inlet and exhaust ports with their respective gas passage conduits. To this end, valve positioning assemblies 74 are provided at each end of common manifold 72. Each valve positioning assembly 74 comprises a plug 101 mounted in the end of common manifold 72 and a spring loaded ball-type detent 102 suitably secured to an end cap 103 mounted on gas passage sleeve 77. Plug 101 is provided with a flange portion 104 which extends radially within end cap103. Formed in flange portion 104'are a plurality of recesses 106 which are adapted to be engaged by spring loaded ball-type detent 102, each recess corresponding-to a desired position of common manifold'72 for providing proper port-passage alignment. Thus, as common manifold 72 is rotated from one alignment position to another by the action of any actuating chains 96 (FIG. 1), the proper alignment of the manifold at thenew'position is insured by the aligning locking action of spring loaded ball-type detent 102 with recesses 106. s v I The operation of the pressure engine of the present invention is as follows: common manifold 72 is positioned as shown in FIGS. 2 and 5 so as to align high pressure fluid supply conduit 82 with passage 80 through check valve 81. Piston 33 is, at this time, positioned atits uppermost position as shown in FIG. 2. High pressure fluid is then admitted through high pressure fluid supply conduit 82, check valye 81, and passage 80 into chamber 31 thereby causing piston 33 to be displaced downwardly from the position shown in FIG. 2 to that shown in FIG. 4. v

As noted above, .downward displacement of piston 33 causes a corresponding downward displacement of connecting rod 35 and pinion 40. Aspinion moves downwardly, it is caused to turn in a clockwise direction by the engagement of the pinion teeth of fixed rack 42. The clockwise rotation of pinion 40 causes a doubled downward movement of tubular double rack 44 by reason of the engagement of the pinion teeth with the teeth 47 of the double rack. The downward movement of tubular double rack 44 causes power gear 50 to rotate in a counterclockwise direction through the interengagement of the teeth of power gear 50 with teeth 48 of the rack. Since the unidirectional clutch 62 is engaged when power gear 50 tends to rotate relatively counterclockwise with respect to load shaft 60, the force transmitted from the piston through the respective gears and racks is imparted to load shaft 60 causing it to rotate counterclockwise as seen in FIG. 2. As noted above, rotation of shaft 60 depends on the size of gear 50, and stroke length and may for convenience, be considered as 220, when a 3" stroke and a 3 gear are used.

Referring to FIGS. l, 2, and 4, an oil level equalizing line 111 is shown communicating with each of the lower casing sections 14. In operation, the sumps 25 of the lower casing sections 14 are filled with oil to some point above the bottom of equalizing line 111. As tubular double rack 44 is moved downwardly by piston 33, it enters lower. casing section 14 and tends to pressurize the oil contained in sump 25 therein. The oil above the level of equalizing line 111 is pumped out therethrough to the sumps of the lower casings of the other cylinder sections 20. Continued downward movement of tubu lar double rack 44 past the level of equalizing line 111 causes the oil to be forced through radial passages 55 into the conduit 52 in guide rod and therethrough upwardly to radial passages 56. The oil is discharged through passages 56 and, because of the orientation of the passages, itis dispersed under the piston and against sleeve 30 to accomplish a complete lubrication of the sleeve and piston surface and, by reason of the downward flow of the oil in returning to the lower casing, the other moving parts in the main casing 12 such as pinion 40 and tubular double rack 44.

As can beseen in FIG. 2, 8356! screw 112 is provided through a threaded opening 114 in the bottom 22 of lower casing section 14. The set screw 112 extends into conduit 52 so as to selectively cover one or more of the radial passages 55 so as to define a metering valve whereby the rate of flow of lubricant to the system and the damping effect can be controlled.

Referring back now to FIGS. 2 and 4, the downward movement of connecting rod 35 with piston 33 ultimately causes engagement of valve-actuating pawl 37 with pivoted valve arm 88. Continued downward movement of connecting rod 35 causes clockwise rotation of valve arm 88 from the position of FIG. 2 to that of FIG. 4. This rotation. in turn, causes a downward displacement of valve rod 90 and a corresponding downward displacement of actuating chain 96. As actuating chain 96 moves downwardly, it causes unidirectional clutch 98 to turn counterclockwise, when viewed in the direction of FIG. 2, which movement causes the clutch to engage and rotate common manifold 72 through 90 from the position corresponding to inlet to that corresponding to exhaust for one cylinder and simultaneously admitting pressure to another cylinder.

With the manifold in this position, passages and exhaust passages 79 are aligned with exhaust port thereby allowing the flow of exhaust gas from within chamber 31 to common manifold 72 and therefrom through exhaust line 86. The cartridge-type ball check valve 81 prevents exhaust gas from entering the inlet manifold 82. With this arrangement, each cylinder goes through a single power-exhaust cycle and then remains at rest for two strokes. Other arrangements are of course possible. For example, if exhaust port 85 passes through both sides of manifold 72, and valve 81 is removed, pressurized fluid will be supplied to the cylinder twice during each rotation of manifold 72, and there will be an exhaust after each power stroke. Alternatively, exhaust port 85 can be drilled in the same plane as valve 81, and the manifold 72 rotated 180 rather than Again, power and exhaust cycles will follow one after the other.

What has been described, therefore, is a simple, fundamental pressure engine which may be used in any application where it is desirable to utilize high pressure fluid to operate a power-generating apparatus. An engine according to the present invention may be made of any size desired and through the use of virtually all stock parts. Since the relationship of the working parts allows a maximum of delivered power with a minimum of wear, the maintenance of the present engine will be kept at a minimum.

Obviously many modifications and variations to the disclosed structure can be made without departing from the spirit and scope of the present invention, as defined in the appended claims and their equivalents.

I claim:

1. A pressure engine comprising:

a. at least two cylinder block sections, two lower casing sections and a main casing section common to the block sections and lower casing sections;

b. piston means mounted for reciprocation in each of said cylinder block sections;

c. a power shaft mounted in said main casing section;

d. valve means for regulating the inlet and exhaust of fluids from said cylinder block sections;

e. a connecting rod operatively secured to each of said pistons and extending into said main casing, said connecting rod for solely axial reciprocation; and

f. means between said connecting rod and said shaft for translating the reciprocating motion of said pistons to rotary motion for driving said power shaft said means comprising a pinion gear mounted on said connecting rod, a fixed rack and a moveable double rack, said moveable double rack operating between said pinion and said power shaft.

2. A pressure engine as claimed in claim 1 wherein said valve includes a rotating manifold, the rotation of which shifts the alignment of said valve means from inlet alignment to exhaust alignment and back to inlet alignment.

3, A pressure engine as claimed in claim 1 and further including: means for force feeding lubricant to the moving parts of said pressure engine, said means for force feeding including said rack.

4. A pressure engine as claimed in claim 1 and further including: a first unidirectional clutch mounted on said power shaft adjacent each of said means for translating; and gear means mounted on each said first clutch means for operatively connecting said moveable double rack with said first unidirectional clutch.

5. A pressure engine as claimed in claim 2 and further including: a pawl mounted on said connecting rod, said pawl for cooperating with a linkage to rotate said rotating manifold from inlet alignment to exhaust alignment.

6. A pressure engine as claimed in claim 3 wherein said valve means includes a rotating manifold, rotation of which manifold shifts the alignment of said valve means from inlet alignment to exhaust alignment and back to inlet alignment.

7. A pressure engine as claimed in claim 6 and further including: a pawl mounted on said connecting rod, said pawl for cooperating with a linkage to rotate said rotating manifold from inlet alignment to exhaust alignment.

8. A pressure engine as claimed in claim 7 wherein said linkage comprises a pivoted arm operatively connected to a reciprocating arm, and a chain for operatively connecting said reciprocating am to a second unidirectional clutch mounted on said rotating manifold.

9. A pressure engine as claimed in claim 8 and further including: a first unidirectional clutch mounted on said power shaft adjacent each of said means for translating; and gear means mounted on each said first clutch means for operatively connecting said moveable rack with said first unidirectional clutch.

10. A pressure engine comprising:

a. at least two cylinder block sections two lower casing sections and a main casing section common to the block sections and lower casing sections;

. a power shaft mounted in said main casing section;

valve means for regulating the inlet and exhaust of fluids from said cylinder block sections, said valve means including a rotating manifold;

e. a connecting rod operatively secured to each of said pistons and extending into said main casing, said connect ing rod for solely axial reciprocation;

f. valve-actuating means for rotating said manifold from inlet alignment to exhaust alignment including a pawl mounted on said connecting rod, linkage means. and detent means on said manifold; and

g. means between each said connecting rod and said shaft for translating the reciprocating motion of said pistons to rotary motion for driving said power shaft, said means comprising: a pinion gear mounted on said connecting rod; a fixed rack and a movable double rack, said pinion gear operating therebetween; a unidirectional clutch mounted on said power shaft adjacent each said translating means; and gear means mounted on said unidirectional clutch for engagement with said moveable rack.

Claims

1. A pressure engine comprising: a. at least two cylinder block sections, two lower casing sections and a main casing section common to the block sections and lower casing sections; b. piston means mounted for reciprocation in each of said cylinder block sections; c. a power shaft mounted in said main casing section; d. valve means for regulating the inlet and exhaust of fluids from said cylinder block sections; e. a connecting rod operatively secured to each of said pistons and extending into said main casing, said connecting rod for solely axial reciprocation; and f. means between said connecting rod and said shaft for translating the reciprocating motion of said pistons to rotary motion for driving said power shaft said means comprising a pinion gear mounted on said connecting rod, a fixed rack and a moveable double rack, said moveable double rack operating between said pinion and said power shaft.

3. A pressure engine as claimed in claim 1 and further including: means for force feeding lubricant to the moving parts of said pressure engine, said means for force feeding including said rack.

8. A pressure engine as claimed in claim 7 wherein said linkage comprises a pivoted arm operatively connected to a reciprocating arm, and a chain for operatively connecting said reciprocating arm to a second unidirectional clutch mounted on said rotating manifold.

10. A pressure engine comprising: a. at least two cylinder block sections, two lower casing sections and a main casing section common to the block sections and lower casing sections; b. piston means mounted for reciprocation in each of said cylinder block sections; c. a power shaft mounted in said main casing section; d. valve means for regulating the inlet and exhaust of fluids from said cylinder block sections, said valve means including a rotating manifold; e. a connecting rod operatively secured to each of said pistons and extending into said main casing, said connecting rod for solely axial reciprocation; f. valve-actuating meanS for rotating said manifold from inlet alignment to exhaust alignment including a pawl mounted on said connecting rod, linkage means, and detent means on said manifold; and g. means between each said connecting rod and said shaft for translating the reciprocating motion of said pistons to rotary motion for driving said power shaft, said means comprising: a pinion gear mounted on said connecting rod; a fixed rack and a movable double rack, said pinion gear operating therebetween; a unidirectional clutch mounted on said power shaft adjacent each said translating means; and gear means mounted on said unidirectional clutch for engagement with said moveable rack.