Abstract: A sub-piston 19 is supported movably in the upward and downward direction on an upper end of a main piston 4 to define an air-fuel mixture cooling chamber 20 between the pistons 4 and 19. The air-fuel mixture cooling chamber 20 communicates with a peripheral edge of a combustion chamber 12. The sub-piston 19 is connected to a cam member 23 which is supported on a crankshaft 7 through a subsidiary connecting rod 21. The volume of the air-fuel mixture cooling chamber 20 is increased and decreased in operative association with the rotation of the crankshaft 7. The air-fuel mixture cooling chamber 20 has an increased volume in a phase from a compression stroke to a point immediately after ignition, and the generation of a knocking is prevented by cooling an air-fuel mixture filled in such air-fuel mixture cooling chamber 20.

Abstract: The fluid expander includes a housing, a drive shaft mounted for rotation within the housing, a piston-cylinder assembly including a cylinder and a piston disposed within the cylinder for converting energy from a working fluid to rotational energy output via a drive shaft. Various adjustment assemblies are provided for adjusting speed, torque, stroke length, and thermodynamic cycles of the device. The fluid expander assembly can be used with external combustion systems, with solar or geothermal energy systems, or with internal combustion systems.

Abstract: A piston for internal combustion engines with an inner piston eccentrically disposed inside the outer piston. The outer piston is attached to a journal at the top of the connecting rod by a wrist pin in the usual manner. The inner piston is attached by a wrist pin to a carrier slidably disposed within the slot of a forked lateral projection extending from the top of the connecting rod. Outer piston movement and inner piston movement relative to the outer piston, produces variable compression and applies torque to the crankshaft while at TDC (top-dead-center).

Abstract: In a connecting rod of a piston machine which comprises two separate parts which are longitudinally movable relative to one another but operatively interconnected and of which one part is connected to the piston and the other is rotatably mounted on the crank of a crankshaft, the two connecting rod parts are interconnected by a fluid spring structure in which a fluid is utilized as a spring element for operatively interconnecting the connecting rod parts.

Abstract: A combustion engine. The engine includes an engine housing; at least one cylinder disposed in the engine housing; and a crank drive including: a crankshaft having a crank; and a piston being axially displaceable within the cylinder. The crank drive further includes a connecting rod which has an upper connecting rod part hinged to the piston; and a lower connecting rod part hinged to the crank. The lower connecting rod part is hinged to the upper connecting rod part. A central joint hinges the upper connecting rod part and the lower connecting rod part to one another, a longitudinal axis of the upper connecting rod part further being defined by a line connecting the central joint with a hinge joint of the upper connecting rod part to the piston.

Abstract: A compression ratio changing arrangement in an internal combustion engine. In order to change the compression ratio by utilizing, to the maximum, an eccentric amount between inner and outer peripheral surfaces of an eccentric ring interposed between a crank pin and a large end of a connecting rod in a compression ratio changing device, the eccentric ring is selectively connected to the crank pin or the large end of the connecting rod by a connecting pin with the thinnest portion or thickest portion of the connecting ring being turned toward the center of rotation of a crankshaft. The selective connection is performed when the piston is at botton dead center. When the eccentric ring has been connected to the crank pin, the stroke of the piston is increased or decreased by an amount corresponding to two times the eccentric amount of the eccentric ring without changing the position of the bottom dead center of the piston, as compared to the stroke with when the eccentric ring has been connected to the large end.

Abstract: This invention is designed to increase the net engine efficiency of four body linkage mechanisms used to generate power or do useful work. This is accomplished by decreasing the piston velocity in the first half of the power stroke of a typical engine cycle. The piston velocity is altered by the addition of three components at the crankarm pin location on the crankshaft. The new components convert a normal engine from a four body to a five body linkage mechanism. One component is an eccentric pin and the other two are an internal ring and pinion gear assembly that indexes and rotates the eccentric pin in a fixed relationship with the crankshaft rotation. The pinion gear and eccentric pin are integral and rotate together as a single part in a direction opposite to the crankshaft rotation. The outer eccentric diameter moves up as the crankarm moves down during the first part of the power stroke.

Abstract: A variable compression ratio apparatus is provided for use in an internal combustion engine. The apparatus has an eccentric sleeve rotatably arranged in one of pivot portions at opposite ends of a connecting rod so as to make a bearing hole of the connecting rod and a pin, which extends through the bearing hole, eccentric relative to each other. The apparatus also has an eccentric sleeve lock device capable of fixing rotation of the eccentric sleeve at a desired position. The lock device includes a pin member engageable with one of engagement portions formed in the eccentric sleeve and a piston-type fluid pressure drive system. The drive system is adapted to produce a pressure difference between fluid pressure chambers formed at opposite sides of a piston portion, which is connected to the pin member, in a state that the fluid pressure chambers are applied with a prescribed fluid pressure, whereby the piston portion is moved to drive the pin member.

Abstract: A compression ratio-changing device for an internal combustion engine, includes an oil passageway formed through a connecting rod of the engine and connected to a hydraulic oil source. A combustion chamber volume-changing device is provided in the piston and operable by means of hydraulic pressure supplied from the hydraulic oil source through the oil passageway for changing the volume of the combustion chamber and hence changing the compression ratio of the engine. A hydraulic pressure control valve is arranged in the connecting rod for controlling the supply of the hydraulic pressure to the combustion chamber volume-changing device. A driving device is provided at a cylinder block of the engine for driving the hydraulic pressure control valve to cause the combustion chamber volume-changing device to change the volume of the combustion chamber.

Abstract: A reciprocating internal combustion engine includes a dual-headed piston body formed by two piston heads mounted at opposite ends of a central yoke structure. The piston heads are adapted to reciprocate within respective opposed cylinders of a coaxially aligned cylinder pair. An internally toothed roller gear is mounted for rectilinear movement within the yoke structure. The roller gear is engageable with a crankshaft drive gear and control and actuator means are provided for effecting sychronized movement of the roller gear within the yoke structure to maintain constant engagement of the roller gear with the crankshaft drive gear as the pistons of the dual-headed piston body reciprocate within respective cylinders of the cylinder pair. The central yoke structure of the dual-headed piston body is adapted to receive roller gears of different size, thus allowing the piston stroke and cylindrical volume of the engine to be varied.

Abstract: A compression ratio-changing device for an internal combustion engine includes a rotary eccentric member rotatably interposed between a piston and a connecting rod, a locking pin for locking the rotary eccentric member to the connecting rod, and a device for driving the locking pin to selectively hold the rotary eccentric member to the connecting rod and release same therefrom. A sliding groove formed in the connecting rod is disposed for parallel alignment with a guide groove formed in the rotary eccentric member when the rotary eccentric member assumes a first angular position for decreasing the volume of a combustion chamber of the engine at a top dead center position of the piston to obtain a higher compression ratio, or a second angular position for increasing the volume of the combustion chamber at the dead center position of the piston to obtain a lower compression ratio.

Abstract: A compression ratio changing device for an internal combustion engine using an eccentric bearing interposed between a piston-pin and a connecting rod. A lock hole is formed in the eccentric bearing and a lock-pin hole is formed in the connecting rod. A lock-pin is slidably inserted in the lock-pin hole and can move into or out of the lock hole. When the lock-pin engages lock hole, the rotation of the eccentric bearing is locked. When the lock-pin moves apart from the lock hole, the rotation of the eccentric bearing becomes free. To obtain a smooth entry of the lock-pin into the lock hole, a guide groove is formed in the outer portion of the eccentric bearing. A portion of the surface of the lock hole forms a colliding surface for colliding with the lock-pin. A deformation absorbing groove is formed at the outer portion of the colliding surface.

Abstract: A device for locking/unlocking rotation of an eccentric bearing interposed between a piston-pin and a connecting rod of an internal combustion engine for changing the compression ratio of the engine. The eccentric bearing has two lock holes, two guide grooves extending circumferentially from the lock holes and two colliding surfaces. The connecting rod has at least one lock-pin hole and a lock-pin is slidably inserted in the lock-pin hole. When the lock-pin is driven toward the eccentric bearing, the lock-pin can move toward the eccentric bearing and can engage the lock hole, thereby locking the rotation of the eccentric bearing. Since the colliding surfaces are provided opposed to said guide grooves, the lock-pin can reliably engage one of the lock holes without jumping the lock hole whether the eccentric bearing rotates in a normal direction or in a reverse direction. As a result, a reliable changing between a high compression ratio and a low compression ratio can be obtained.

Abstract: For changing the compression ratio of a reciprocating piston internal combustion engine the piston 3 consists of an outer piston part 7 and an inner piston part 10 which are connected with each other by a thread 13,14. By turning the outer piston part 7 by means of a bushing 18 which is axially fixed, but rotatable around piston axis 15 and which is in engagement with the outer piston part 7 by means of a longitudinal gear 19,20, the outer piston part 7 can be turned steplessly during operation with respect to the inner piston part 10, whereby the outer piston part 7 is displaced along the piston axis 15, thus changing the volume of the operating chamber and thereby the compression ratio.

Abstract: A yoke type engine wherein the orbital path of the slider is alterable to effect piston stroke and compression ratio changes. A crank component has a crankpin which carries and positions the slider. A boss of the crank component is carried by a control shaft in an offset manner. Timing gears normally drive the control shaft in synchronization with the crankshaft to maintain a constant stroke and compression ratio. Relocation of certain timing gears by an actuator causes the control shaft to rotationally advance or retard to reposition the crank component carried thereby to in turn alter the orbital path of the coaxial crankpin and slider relative to a crankshaft axis. Accordingly, high and low compression orbits for the slider may be effected to best suit engine loads. A variable length throw couples the slider to the crankshaft. The orbital path of the slider provides increased crankshaft leverage over conventional engine arrangements.

Abstract: A reciprocating piston engine, pump or compressor including a crank-shaft having a crank-pin offset laterally from the axis of rotation of the crank-shaft, a connecting-rod pivotally-mounted on the crank-pin and pivotally-connected at the end thereof remote from the crank-pin to a piston, the axis of pivoting of the connecting-rod on the crank-pin being offset laterally from the longitudinal axis of the crank-pin, a non-rotatable gear mounted co-axially of the crank-shaft axis of rotation and a rotatable gear wheel mounted co-axially on the crank-pin for rotation thereon and in mesh with said non-rotatable gear, the connecting-rod being mounted on the rotatable gear for pivoting about an axis offset laterally from the longitudinal axis of the crank-pin, whereby the axis of pivoting of the connecting-rod on the crank-pin follows a predetermined locus as the crank-shaft is rotated.

Abstract: A spring-loaded piston is slidably arranged in an auxiliary chamber opening into the combustion chamber of an internal combustion engine. The spring-loading of the piston is preset so that the piston retracts at a certain high pressure attained during the combustion process, thereby increasing the combustion chamber volume. This enables higher compression ratios to be used than is otherwise possible.