Abstract: An engine body supports a cylinder having a piston reciprocally mounted therein. A connecting rod is pivotally connected between the piston and a lever which is pivotally supported by the engine body. The lever rotatably supports a drive roller which is disposed in contact with a cam surface on a member drivingly connected to an output shaft. The connecting rod may be connected to the lever by a connecting pin which is mounted for movement within slots formed in the lever. A crank is pivotally connected to the connecting pin to adjust the position of the connecting pin within the slots to control reciprocal movement of the piston. In a modification, the levers connected to adjacent pistons are connected to one another for movement together and are pivoted about a common pivot axis. In another embodiment, a novel cam profile provides unequal piston strokes to operate the engine in an overexpanded operating cycle.

Abstract: An internal combustion engine comprising: a piston (2) and a cylinder (3), the piston (2) being sealedly mounted to the cylinder (3) and being reciprocally mobile therein between a Top Dead Center (TDC) and a Bottom Dead Center (BDC); also comprising a combustion chamber (4) delimited by the piston (2) and the cylinder (3); a crankshaft (5) provided with a crank (5m) pin (5p); a connecting rod (6) having a small end (6p) rotatably connected to the piston (2) and a big end (6t) rotatably connected to the pin (5p) of the crank (5m) of the crank shaft (5), also comprising at least one cam (7), mounted, rotatably and freely mobile on the big end (6t) of the connecting rod (6) and on the pin (5p) of the crank (5m), which cam (7) by effect of inertia consequent to a rotation of the crank (5m), moves cyclically rotatingly with respect to the pin (5p) and the connecting rod (6) between two operative positions, in which it transmits to the connecting rod (6) an action which adds to the inertia actions of the connectin

Abstract: A device for changing compression of an internal combustion engine, wherein the internal combustion engine has a cylinder, a piston reciprocating in the cylinder, a crankshaft having a crank, and a connecting rod having a first end connected to the crank and a second end connected to the piston, includes an eccentric bushing resting with an inner cylindrical surface on the crank and with an eccentric outer cylindrical surface at the connecting rod so that by rotating the eccentric bushing relative to the connecting rod an effective length of the connecting rod is changed. The eccentric bushing has a least two locking recesses. A locking member is connected to the connecting rod and moveable in different directions into one or the other of the at least two locking recesses for locking the eccentric bushing in a first and second rotational position.

Abstract: An adjustable stroke reciprocating mechanism which includes a reciprocating member mounted for reciprocating movement, a rotating member mounted for rotation about a main axis (XX), a connecting rod operatively connected to the reciprocating member and a crank assembly including a crank arm having a longitudinal axis (Y) which is inclined with respect to the main axis (XX). At least a portion of the crank arm can revolve about the main axis, the connecting rod being operatively connected to the crank arm and its position adjustable along the length thereof in either direction along a longitudinal axis (Y). There is also provided various bearing mounting assemblies for use with the adjustable stroke reciprocating mechanism and carrier and shaft assemblies allowing controlled movement along the longitudinal axis (Y) of the crank arm.

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 compression ratio is variable in that the piston hub may be adjusted, since the connecting rod is mounted at the crankshaft side on an eccentric pin. The eccentric crank pin can be adjusted around its axis of rotation by control means while the engine is running. The control means include a toothed wheel that turns concentrically to the axis of rotation of the eccentric crank pin and is fixed thereto. This toothed wheel acts as an external gear inside a larger diameter internal gear inside which it rolls. The internal gear is concentrically mounted around the axis of the crankshaft and its rotating position may be adjusted. The external gear turns exactly once upon itself every time it rolls round the internal gear.

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: A variable compression ratio internal combustion engine has a piston connected to a crank pin on the crankshaft by means of a connecting rod formed in two parts, with the first part being rotatably secured to the crankshaft, and the second part being rotatably secured to a gudgeon pin of the piston. The two parts are connected to each other by a coupling including two eccentrics having axes of eccentricity that are inclined to one another so that the eccentrics cannot both lie in a dead center position at the same time.

Abstract: A variable stroke engine includes first and second pistons mounted in respective cylinders for reciprocal linear movement. The engine also includes first, second, and third parallel crankshafts. A first connecting assembly connects the first piston to the first and second crankshafts. A second connecting assembly connects the second piston to the second and third crankshafts. Each connecting assembly includes first and second connecting rods arranged in a crossing relationship with each other. A first set of synchronizing gears establishes co-rotation of the first and second crankshafts and synchronizes a first angular phase relationship between the first and second crankshafts. A second set of synchronizing gears establishes co-rotation of the second and third crankshafts and synchronizes a second angular phase relationship between the second and third crankshafts.

Abstract: An improved piston-cylinder internal combustion engine alters the volume of the combustion chamber without relying on movement of the piston to change the volume of the combustion chamber.

Abstract: A variable stroke engine has a piston slidably mounted in a cylinder for reciprocal linear movement therein. The engine includes first and second parallel crankshafts having first and second crank pins, respectively. A connecting assembly connects the piston to the first and second crankshafts. The connecting assembly includes an oscillating member pivotally connected to the piston at a first connection. The assembly further includes first and second connecting rods rotatably connected to the first and second crank pins, respectively. The first and second connecting rods are further rotatably connected to the oscillating member at respective second and third connections. The second and third connections are offset from the first connection and offset from each other such that the first and second connecting rods are arranged in a crossing relationship. Synchronizing gears establish co-rotation of the first and second crankshafts and synchronize an angular phase relationship between the crankshafts.

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: A stirling engine or an internal combustion engine having one or more cylinders, each having a moveable piston which is coupled to a drive shaft to drive a load. The engine load coupling also includes a set of Class 1 elliptical gears of the first type which means each gear rotates about one of its focal points. The load and the engine are efficiently operated as a result of the operation of the coupling arrangement. In apparatus employing a Stirling engine, apparatus and engine efficiencies are enhanced through elliptical gear operation which enables the Stirling engine to operate very closely to the idealized Stirling cycle.

Abstract: A variable compression height piston for reciprocating internal combustion engine includes a lower piston coupled to a connecting rod and an upper piston slidably carried upon the lower piston. A hydraulically actuated mechanical latching system interposed between the lower and upper pistons allows a system controller to selectably maintain the upper piston in a plurality of predetermined compression heights.

Abstract: In an internal combustion engine, an eccentric bearing (16) located between the connecting rod (14) and the piston pin (12) can be used to vary the compression ratio. In this invention the eccentric bearing is held in any position by a continuously variable hydraulic lock. The hydraulic lock is controlled by a valve assembly (30) which can fix or release the lock bar (18). When the lock bar is released the eccentric bearing can turn as a result of the upward or downward inertia and gas pressure forces on the piston (10). However, a check valve (34) in the valve assembly allows it to turn only in the direction set by the valve assembly until it reaches the new position and re-locks. Engine oil is provided at regulated pressures through oil passages in the connecting rod, eccentric bearing and piston pin to set the position of the valve assembly and to provide a supply for the hydraulic lock.

Abstract: A variable displacement engine includes a rotatable crankshaft having a journal, a cam having an eccentric opening that receives the crankshaft journal, a piston rod assembly having one end journalled on the eccentric cam, and the cam also having an arcuately extending cavity that has gear teeth formed in its outer wall that are at a constant radius distance from the radial center of the eccentric opening, and a gear wheel disposed within the cavity and engaging the gear teeth for selectively adjusting the angular position of the cam relative to the crankshaft journal.

Abstract: Controlled variation of piston .displacement and adjustment of compression ratio are achieved by an adjustment mechanism located between the vehicle crank shaft and the piston which changes the effective length of the piston rod. The piston rod is divided into upper and lower portions and the adjustment mechanism connected to both portions at the point of division. The adjustment mechanism allows controlled lateral displacement of the two parts of the piston rod from each other at the point of division while still transmitting energy of motion from the piston to the crank shaft.

Abstract: An apparatus for converting reciprocating motion to rotary motion and vice-versa. The apparatus includes a reciprocatory assembly guided for reciprocation in a first direction. The reciprocatory assembly includes first and second reciprocating members each terminating in a planar guide surface transverse to the direction of reciprocation; spacing tie means interconnecting the two reciprocatory members at opposite ends of the guide surfaces to maintain the guide surfaces parallel, spaced apart and facing each other; a drive block having opposed guide faces each slidably engaged with a respective one of the guide surfaces of the reciprocatory members; and a rotary member mounted for rotation about an axis transverse to the direction of reciprocation and having an eccentric portion rotatably engaged in the drive block.

Abstract: A compression ratio control system consists of a two-part piston forming a hydraulic chamber between the two slidable parts; their relative position, which determines the piston height, is controlled outside of the engine by regulating the pressure of engine oil going to the crankshaft and channeled to the hydraulic chamber through the crank mechanism. Piston height adjustment is accomplished incrementally by balancing the oil pressure against the momentary cylinder pressure transmitted to the hydraulic chamber, for a short interval at a predetermined angular crankshaft position, using a timing device located at the crankshaft end of a piston rod. The timing device consists of a set of small valves operated by inertial forces; with respect to the oil flow, these valves are arranged in series and on different timing given by their angular orientation, so as to open the oil passage during their opening overlap once per cycle.

Abstract: A variable stroke piston system (10). The effective length of the stroke of an internal combustion engine is increased by extending end lobe (14) from main lobe (16) by means of extension rod 18. Extension rod (18) may be operated hydraulically, mechanically or electrically.

Abstract: A reciprocating piston is disclosed with variable compression height for internal combustion engines in particular. For structural simplification of the temperature-dependent change in the compression height of the reciprocating piston, a spring is provided which consists of a shape memory alloy and interacts with the pressure limiting valve. This permits temperature-dependent change in the compression height of the reciprocating piston exclusively by the pressure limiting valve so that structural simplification is achieved.

Abstract: This invention relates to a two piece piston with a variable compression height, wherein a piston top part can be adjusted with respect to a piston bottom part along the longitudinal axis of the piston preferably by hydraulic devices and can be caused to perform a progressive rotating movement. This rotating movement is achieved by means of two thread sections of opposed pitch which, depending on the moving direction of the piston top part, alternately engage in corresponding counterthread sections on the piston bottom part. These threads and counterthreaded sections are multiple coarse pitch threads and are located on one side only as flanks disposed in the moving direction of the piston top part so that when the moving direction of the piston top part is reversed, a moving-apart of the engaged thread sections and counterthread sections occurs and the thread sections with an opposed pitch engage correspondingly on the flanks on the corresponding counterthread sections.

Abstract: A variable compression ratio device for an internal combustion engine includes a connecting rod having passages formed therein for communicating a hydraulic signal to the piston attached to the connecting rod, means for generating a hydraulic signal having a signal characteristic which is indicative of a desired compression ratio, and a variable compression height piston which is positionable in a plurality of compression heights, including fully retracted, fully extended, and at least one position therebetween, with the piston having an outer section slidably mounted on an inner section, and with the inner section being attached to the connecting rod, with the piston having means responsive to inertia and gas pressure forces and to the generated hydraulic signal for controlling the compression height.

Abstract: A connecting rod crankshaft bearing, provided for installation in the connecting rod at the crankshaft end, eliminates the necessity for reaming out the ridge in a cylinder during rebuilding. The rod bearing is an eccentric bearing, provided as two semi-circular sections having a slightly greater thickness along the lower section than on the upper section so as to offset the center of the inner surface from the outer surface of the bearing.This offset restricts the uptravel of the connecting rod. This in turn lowers the position of the piston during reciprocating travel by the same amount, eliminating possible impact with wear ridges within the cylinder. The cylinder thus need not be reamed to remove these ridges, as they no longer present a source of damaging impact during piston travel.

Abstract: A combination hydraulic and mechanical mechanism for varying the stoke/clearance volume of an engine in response to the alternating torsional impulses of the engine that are applied through the piston and connecting rod mechanism. An eccentric on which the connecting rod is journaled is rotated relative to the crankshaft to vary the crank radius, which will vary the compression ratio and make other changes in the thermodynamic cycle. A fluid pressure control system includes a pressure movable shaft controlling the flow of fluid past one-way check valves to oil filled hydraulic cylinders that contain pistons/plungers operably connected to the eccentric and crankshaft, to control the movement of the eccentric in response to the torsional impulses.

Abstract: An automotive-type engine has each of the piston connecting rods connected to the engine crankshaft by means of a swing link that is pivoted at one end to the arm of a normally stationary crank; however, the crank can be rotated to change the clearance volume between the piston and the cylinder head or the stroke of the engine for best engine operation at each operating condition. A piston/plunger hydraulically interconnects the crank arm to a control means for permitting rotation of the crank arm by means of a number of cam-controlled pushrods operating on one-way check valves controlling flow of fluid from opposite ends of the chamber containing the piston/plunger.

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 new and useful improvement to internal combustion engines is disclosed which is an engine with an offset crankshaft. When the crankshaft is rotated in a clockwise direction, the distance the piston travels from the top of the stroke (piston at maximum travel) to the bottom of the stroke (piston at the bottom of its travel) is greater than the diameter of the crankshaft rotation. The angle through which the crankshaft moves during the downstroke is greater than 180.degree.. The engine therefore has a longer time power stroke than exhaust stroke. The intake cycle is longer in time than the exhaust cycle which improves aspiration of the engine. This concept can be applied to Otto cycle engines, Diesel engines, two stroke engines, and may be applied to compressors. When used in compressors, the intake stroke is extended which improves aspiration.

Abstract: The present invention contemplates a mechanically simply constructed mechanism located internally of a piston engine for adjustably changing the stroke of a piston over a predetermined range in response to a variety of operating control parameters. The adjustable stroke changing mechanism provides an optimum compression ratio at each change in piston stroke and over the entire range of piston stroke provided which may be varied from one piston engine to another of different performance characteristics without requiring a major change in design of the stroke changing mechanism. The stroke changing mechanism includes a swing plate pivotally fixed to the engine block at one end and placed intermediate the piston connection rod and respective crankshaft pin at its other end, each of which are affixed to and translate within the swing plate as the piston is driven to reciprocate within a piston cylinder.

Abstract: A two stroke reciprocating internal combustion or external compression engine which has at least two of needed power connecting posts mounted on each end of a carrier mechanical assembly which slides in a guided area by virtue of the engine's stator design. In the carrier assembly there is incorporated an oval-type, internally toothed gear track which moves in reciprocating, linear motion. A circular, externally toothed gear is mounted on a rotatable, floating power shaft which extends perpendicular to the carrier. In that the gear is in constant engagement with the oval gear track, it is rotated by the linear movement of the reciprocating carrier. Proper gear engagement is insured by either a guider plate of by interlocking rollers in the carrier assembly. The output power end of the floating shaft is received in a mechanical unit which couples the floating shaft to an output shaft for use.

Abstract: The present invention relates to a mechanism for transforming a reciprocating motion and a rotating motion from one to the other, and more particularly to a crankless engine in which in place of a crank shaft there is used a rocking member having a rockable fulcrum and adapted to perform rocking motions without rotating on its own axis, like a spherical bearing or a cross-type universal bearing. The above motional transformation is effected in high mechanical efficiency by pivotal connection between the said rocking member and a rotary shaft. The compression ratio can be changed, and the engine is durable.

Abstract: The engine is characterized by an axial group of two cylinders (2, 7) communicating by means of a channel (22) situated in the cylinder head (20). Both cylinders (2, 7) joined side to side allow for a centralization of both crankshafts (4, 13) in the cylinder case (5). Each cylinder comprises a corresponding piston (1, 6) displaceable in the first cylinder (2) intended for the intake, compression, expansion and exhaust phases, said first piston (1) depending, via a piston rod (3), from the first crankshaft (4) situated in the cylinder case (5). The second piston (6) displaceable within the second cylinder (7) delimiting the combustion prechamber (8) wherein are housed a heating plug and a fuel injector, said second piston (6) depending, via a piston rod (12), from the second crankshaft (13) also located in cylinder case (5).

Abstract: The invention relates to a piston having a variable compression height and two control chambers connected to each other through a hydraulic system. In order to achieve better cold-start and warm-up behavior, an oil discharge bore from the upper control chamber into the crankcase is closed by a control slide valve in the cold operating state of the engine. The blockage of the oil discharge produces a great compression height and therefore high compression. The control slide valve is connected to an expansible element which maintains it in this closed position when the engine is cold. As the engine warms up, the expansible element, due to its thermal expansion, pushes the control slide valve out of its closed position, so that the discharge of oil can occur progressively more unthrottled with rising temperature. In the warm operating state of the engine the control slide valve clears the oil discharge duct completely, and an unobstructed discharge of oil is ensured.

Abstract: A compound rod, sleeve and an offset crankshaft assembly for post crankshaft top dead center-top dead center piston assembly is invented for an internal combustion engine and other machines. The piston includes a crown or head and a skirt and is connected to a first connecting rod by a second connecting rod. A separate sleeve is provided and attached to the linkage by the first connecting rod. The piston and the sleeve are kinematically linked to each other and to the crankshaft of the engine by the two connecting rods, so that the piston crown or head is raised to a maximum elevation after the top dead center of the crankshaft rod journal which occurs during the compression stroke and exhaust stroke of the piston. The second connecting rod is connected to the crankshaft of the engine by the first connecting rod.

Abstract: A driving or working engine, in particular an internal combustion engine, having at least one cylinder and a piston which moves axially in the latter and is connected to the crankshaft by an upper section of the connecting rod and a lower section of the connecting rod connected to the said upper section by a hinge. The two sections of the connecting rod are supported on an adjustable axle integral with the engine housing by a common hinged pivoting lever. In order to increase output and permit adaptation to different fuels, the end of the upper section of the connecting rod (5, 30) facing the piston (2) has an axial prolengation (27) which passes through the common hinge (9, 33) of the two sections of the connecting rod (5, 10 and 30, 35), and the end (14", 36, 36') of the pivoting lever (14, 39) facing the two said sections of the connecting rod (5, 10 and 30, 35) engages in an articulated manner with the prologation (27).

Abstract: The pressure prevailing in a variable volume chamber which controls the compression ratio developed by a piston, is used control the movement of a valve which regulates the supply and draining of the chamber. During high load the high pressure is used to drain the chamber while under light load the lower pressure permits the chamber to be supplied with hydraulic fluid in a manner which tends to fill the same during induction phases and the like when the pressure in the cylinder is low.

Abstract: Novel internal-combustion engines of the swing beam type incorporate an improved construction utilizing a Rapson slide motion and also are derived from two or three degree of freedom mechanisms for controlling the displacement of the piston as a function of crankshaft displacement and of the displacement of a control shaft. The control shaft either operates at an average speed which is preferably a prescribed ratio of crank speed, thereby yielding an improved thermodynamic cycle (such as the Atkinson cycle in the case of a four-stroke engine) and cycle timing, or functions as a lever for obtaining variable stroke operation. The mechanism can also incorporate a continuously rotating control shaft together with a second control shaft functioning as a lever, thereby yielding an improved thermodynamic cyle and cycle timing together with variable stroke operation. The control shaft, functioning as a lever, can be replaced by a similar actuating device.

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 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 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: To induce high compression engine operation hydraulic fluid is fed into a variable volume chamber defined between an outer piston and an inner one which is reciprocatively disposed therein via a supply passage which includes a one-way valve. When low compression engine operation is required the pressure supplied to a valve chamber in which a spool valve is disposed is increased to the point whereat the spool valve moves to a position wherein the supply passage is closed and a drain and transfer passages are opened. The drain passage leads directly to the cylinder bore so as to enable the hydraulic fluid in the variable volume chamber to be vented unrestrictedly. The transfer passage permits a small amount of hydraulic fluid to flow through the variable volume chamber to the drain passage in a manner which cools the same and prevents degradation of the hydraulic fluid retained in the one-way valve and the like.

Abstract: The invention relates to a piston with variable compression height, particularly for internal-combustion engines, that consists of an interior piston part to which a connecting rod is coupled, and an exterior piston part that is slidably held at said interior piston part. In this case, the exterior piston, via two control chambers that are supplied with oil from the lubricating oil circuit, supports itself by adherence at the interior piston part, said control chambers being connected by a hydraulic system.

Abstract: In an internal combustion engine, an improved mechanism for adjusting the rotational axis of the crankshaft to vary the engine compression ratio. The crankshaft is supported at spaced points therealong in circular disks that are swivably adjustable about their central axes. The crankshaft rotational axis is eccentric to the disk axis, whereby disk adjustment moves the crankshaft axis in a direction to vary the engine 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: The present invention relates to an apparatus for converting between reciprocating motion and rotational motion, and particularly involves such an apparatus used as a power output mechanism for an internal combustion engine. The end of a piston rod is connected to a cam device which follows a closed loop path defined by a cam track. The closed loop path includes a pair of generally parallel, substantially straight portions. The substantially straight portions of the closed loop path are disposed at an angle of greater than 90.degree., but less than 180.degree. to the longitudinal axis of the cylinder in which the piston travels.

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: An internal combustion engine comprising an engine block, a piston, a crankshaft, a lever, a piston connecting rod, and a crankshaft connecting rod. The engine block defines a cylinder chamber, and the piston is supported for reciprocating movement therein. The crankshaft is rotatably supported by the engine block and includes an eccentric portion. The lever includes first and second ends and an intermediate portion located therebetween, and the first end of the lever is pivotally connected to the engine block. The piston connecting rod includes a first end pivotally connected to the intermediate portion of the lever and a second end pivotally connected to the piston. The crankshaft connecting rod includes a first end pivotally connected to the second end of the lever and a second end pivotally connected to the eccentric portion of the crankshaft.