Abstract: In an internal combustion engine, a variable compression ratio mechanism able to change a mechanical compression ratio and a variable valve timing mechanism able to control the closing timing of an intake valve are provided. At the time of engine low load operation, the mechanical compression ratio is made the maximum so that the expansion ratio becomes 20 or more. Further, at the time of engine low load operation, in part of the operating region or all of the operating region, the actual compression ratio is lowered compared with the time of engine high load operation and, at the time of engine low load operation, at least when the actual compression ratio is being lowered compared with the time of engine high load operation, the throttle valve is made to close.

Abstract: An exhaust heat recovery apparatus includes: an exhaust heat recovery unit that produces motive power by recovering thermal energy from exhaust gas discharged from a heat engine; an electric generator that is driven by the exhaust heat recovery unit; a first power transmission-switching device that switches between connection and disconnection between the heat engine and the exhaust heat recovery unit; and a second power transmission-switching device that switches between connection and disconnection between the exhaust heat recovery unit and the electric generator, wherein the heat engine or the electric generator is selectively connected to the exhaust heat recovery unit, depending on the operational status of the heat engine. The exhaust heat recovery apparatus makes it possible to effectively use surplus motive power produced by an exhaust heat recovery unit.

Abstract: An engine provided with a variable timing mechanism (B) able to control a closing timing of an intake valve (7) and a variable compression ratio mechanism (A) able to change a mechanical compression ratio. At the time of engine startup, the closing timing of the intake valve (7) is made the most delayed position so that the least intake air is fed to the inside of the combustion chamber (5) and the mechanical compression ratio is made the maximum compression ratio.

Abstract: A power transmission mechanism that transfers power from an output shaft disposed in sealed-off space within a power generation unit includes: a drive shaft to which the power from the output shaft is transmitted; a first magnet that is fitted to the drive shaft and that rotates together with the drive shaft; a second magnet that is fitted to a driven shaft, which is arranged concentrically with the drive shaft, that is disposed outside the sealed-off space, and that faces the first magnet; and a partition wall that is interposed between the first magnet and the second magnet, and that separates a drive shaft side space and a driven shaft side space from each other.

Abstract: In an engine 10, oxygen, hydrogen serving as fuel, and argon gas serving as a working gas are supplied to a combustion chamber 21. An upstream condenser section 70 condenses water vapor contained in an exhaust gas to yield primary condensed water, through heat exchange of the exhaust gas from the combustion chamber with the ambient air, and discharges, as a primary-condensed-water-separated gas, a gas obtained by separating the primary condensed water from the exhaust gas. The primary condensed water is stored in a water storage tank 100. A downstream condenser section 80 further condenses water vapor contained in the primary-condensed-water-separated gas to yield secondary condensed water, through utilization of latent heat of vaporization of condensed water stored in the storage tank 100, and discharges a gas obtained by separating the secondary condensed water from the primary-condensed-water-separated gas. This avoids a significant drop in ratio of specific heats of the working gas.

Abstract: A stirling engine includes a flow path which communicates a working space of the stirling engine and a crankcase of the stirling engine. An output of the stirling engine is controlled so that the output lowers when a pressure inside the working space is higher than a pressure in the crankcase, with a transfer of a fluid in the working space to the crankcase via the flow path thereby causing a decrease in the pressure of the working space.

Abstract: A piston apparatus which configures an air bearing by introducing a compressed working media into an inside of a piston, and ejecting the working media from plural holes arranged on a circumferential portion of the piston into a clearance between the piston and the cylinder, which prevents a back-flow of the working media in the piston to a working space, and which readily secures reliability and longevity is provided.

Abstract: In order to decrease internal friction of a heat engine that converts a reciprocating motion of a piston into a rotational motion, a piston apparatus (1) forms an air bearing between a crankshaft (30) and a bearing unit (9B) provided in a crankcase (9) and between an eccentric portion (30c) of the crankshaft (30) and a large end portion (201) of a connecting rod (20) by feeding a gas therebetween from a crank-side hollow portion (31) of the crankshaft (30). The piston apparatus 1 also forms an air bearing between a piston pin (40) and a small end portion (202) of the connecting rod (20) by feeding a gas therebetween from a piston pin-side hollow portion (43) in the piston pin (40).

Abstract: An operating gas circulation type internal combustion engine that uses argon as the operating gas, for example, and includes a hydrogen and oxygen supply portion, an argon supply amount regulating portion, and an electric control unit. The electric control unit determines the amount of hydrogen and oxygen to be supplied to a combustion chamber based on a required torque, which is the torque required of the internal combustion engine, and supplies the determined amounts of hydrogen and oxygen to the combustion chamber using the hydrogen supply portion and the oxygen supply portion. Further, the electric control unit determines an amount of operating gas to be supplied to the combustion chamber according to the required torque, and controls the argon supply amount regulating portion such that the determined amount of operating gas is supplied to the combustion chamber.

Abstract: An internal combustion engine provided with a variable compression ratio mechanism able to change a mechanical compression ratio and an actual compression action start timing changing mechanism able to change a start timing of an actual compression action. An amount of intake air in accordance with the required load is fed into a combustion chamber by controlling the closing timing of the intake valve, while a pressure, temperature or density in the combustion chamber at the end of a compression stroke is maintained substantially constant regardless of the engine load by controlling the mechanical compression ratio.

Abstract: An exhaust heat recovery apparatus includes a first piston; a second piston; a first cylinder in which the first piston reciprocates; a second cylinder in which the second piston reciprocates; and a heat exchanger. The heat exchanger includes a heater that is independently shiftable with respect to at least one of the first cylinder and the second cylinder, and has one end portion arranged at a side of the first cylinder and receiving heat from heat medium, a regenerator that is arranged at a side of another end portion of the heater, and a cooler that has one end portion arranged at a side of the regenerator and another end portion arranged at a side of the second cylinder.

Abstract: A stirling engine includes a flow path that communicates a working space of the stirling engine and outside of the stirling engine. A working gas is supplied from the outside of the stirling engine to the working space via the flow path based on a differential pressure of the working space and the outside of the stirling engine.

Abstract: In an engine 10, oxygen, hydrogen serving as fuel, and argon gas serving as a working gas are supplied to a combustion chamber 21. An upstream condenser section 70 condenses water vapor contained in an exhaust gas to yield primary condensed water, through heat exchange of the exhaust gas from the combustion chamber with the ambient air, and discharges, as a primary-condensed-water-separated gas, a gas obtained by separating the primary condensed water from the exhaust gas. The primary condensed water is stored in a water storage tank 100. A downstream condenser section 80 further condenses water vapor contained in the primary-condensed-water-separated gas to yield secondary condensed water, through utilization of latent heat of vaporization of condensed water stored in the storage tank 100, and discharges a gas obtained by separating the secondary condensed water from the primary-condensed-water-separated gas. This avoids a significant drop in ratio of specific heats of the working gas.

Abstract: An internal combustion engine provided with a variable compression ratio mechanism able to change a mechanical compression ratio and an actual compression action start timing changing mechanism able to change a start timing of an actual compression action. The mechanical compression ratio is made maximum so that the expansion ratio becomes 20 or more at the time of engine low load operation, while the actual compression ratio at the time of engine low load operation is made an actual compression ratio substantially the same as that at the time of engine high load operation.

Abstract: A spark ignition type internal combustion engine comprises a variable compression ratio mechanism able to change a mechanical compression ratio, an actual compression action start timing changing mechanism able to change a start timing of an actual compression action, and an exhaust valve. At the time of engine low load operation, the mechanical compression ratio is maximized to obtain a maximum expansion ratio, and the actual compression ratio is set so that no knocking occurs. The maximum expansion ratio is 20 or more. The closing timing of the exhaust valve at the time of engine low load operation is made substantially intake top dead center. Due to this, even if operating the internal combustion engine in a state of a large expansion ratio, the temperature of the exhaust purification catalyst can be maintained at a relatively high temperature.

Abstract: An exhaust heat recovery apparatus includes a Stirling engine and a clutch. The Stirling engine produces motive power by recovering thermal energy from exhaust gas discharged from an internal combustion engine from which exhaust heat is recovered. The motive power produced by the Stirling engine is transmitted to an internal combustion engine transmission through the clutch and an exhaust heat recovery device transmission, and combined with the motive power produced by the internal combustion engine through the internal combustion engine transmission, and is output from an output shaft. If rapid acceleration is required, and the increase in the rotation speed of the Stirling engine therefore lags behind the increase in the rotation speed of the internal combustion engine, the clutch is released. With this configuration, reduction in the power output from the heat engine, from which exhaust heat is recovered, is restricted, and the degradation of the acceleration performance is minimized.

Abstract: An exhaust heat recovery apparatus includes a reciprocating internal combustion engine in which a piston reciprocates in a cylinder to generate motive power; and a Stirling engine that recovers the thermal energy of the exhaust gas discharged from the internal combustion engine and converts the thermal energy into kinetic energy. The Stirling engine is united with the internal combustion engine. A heater that the Stirling engine includes is disposed in an exhaust manifold of the internal combustion engine. With this configuration, it is possible to restrict reduction in the power output from the exhaust heat recovery means.

Abstract: An engine provided with a variable timing mechanism (B) able to control a closing timing of an intake valve (7) and a variable compression ratio mechanism (A) able to change a mechanical compression ratio and controlling the closing timing of the intake valve (7) to control the amount of intake air fed into a combustion chamber (5). To obtain an output torque in accordance with the required torque even when the atmospheric pressure changes, when the atmospheric pressure falls, the closing timing of the intake valve (7) is made to approach intake bottom dead center and the mechanical compression ratio is reduced.

Abstract: In order to decrease internal friction of a heat engine that converts a reciprocating motion of a piston into a rotational motion, a piston apparatus (1) forms an air bearing between a crankshaft (30) and a bearing unit (9B) provided in a crankcase (9) and between an eccentric portion (30c) of the crankshaft (30) and a large end portion (201) of a connecting rod (20) by feeding a gas therebetween from a crank-side hollow portion (31) of the crankshaft (30). The piston apparatus 1 also forms an air bearing between a piston pin (40) and a small end portion (202) of the connecting rod (20) by feeding a gas therebetween from a piston pin-side hollow portion (43) in the piston pin (40).

Abstract: An exhaust heat recovery apparatus (functioning as a Stirling engine), which is installed in, for example, an exhaust passage of an internal combustion engine and an exhaust passage of factory exhaust heat as restraining reduction in exhaust heat recovery efficiency, is installed in a device installing surface formed in the heat medium passage so that the device installing surface and a heater connecting side end surface of a high temperature side cylinder become parallel and the device installing surface and a cooler connecting side end surface of a low temperature side cylinder become parallel. The high temperature side cylinder is arranged at an upstream side of a direction of exhaust flow. The low temperature side cylinder is arranged at a downstream side of the high temperature side cylinder.