Abstract: This invention provides a pre-combustion chamber gas engine capable of being applied to a two-stroke gas engine using a natural gas as fuel. A gas fuel is supplied to precombustion chambers with communication ports, which allows communication between primary chambers and pre-combustion chambers, closed with control valves provided therein, and suction air is supplied to cylinders and compressed under a high pressure. Even when the suction air is compressed under a high pressure in the primary chambers, the self-ignition of gas fuel does not occur therein since a gas fuel does not exist therein, so that knocking does not occur. Each of the control valves provided in the communication ports is constructed so that a lift amount thereof can be varied by a controller.

Abstract: A differential includes a planet gear through which two shafts coupled to laterally spaced road wheels of a motor vehicle are interconnected. The planet gear has a rotatable shaft with a brake mechanism coupled thereto. A braking force produced by the brake mechanism is transmitted through the differential to the road wheels depending on the rotational speeds of the road wheels. The brake mechanism may include either a turbine for producing a resistive force upon rotation thereof or a hydraulic damper comprising a hydraulic pump and a variable restriction.

Abstract: A slidable ceramic member includes a base of a sintered ceramic material which is a compound including silicon (Si) as a constituent element, the base having a sliding surface, and a coated layer covering the sliding surface of the base, the coated layer comprising a compound of elements, such as barium (Ba) and calcium (Ca), belonging to group IIa of the periodic table, silicon (Si), and oxygen (O). The slidable ceramic member is used as a slidable component of a heat engine such as a cylinder liner or a piston ring which is subjected to repeated thermal stresses. Such a slidable ceramic member is manufactured by placing powder of a fluoride including elements belonging to group IIa of the periodic table on a surface of a base, and heating the base while rubbing the powder against the surface of the base, whereby the silicon (Si) contained in the base and the group-IIa elements contained in the powder can react with each other, thereby forming a slidable layer on the surface of the base.

Abstract: The present invention lies in a 2-4 cycle change-over engine and its control unit which perform 2 cycle running of the uniflow type by closing a suction valve at an upper portion of the engine and working a valve (a rotational sleeve) at a lower portion of a cylinder when the engine rotates in a lower number of revolution than a predetermined number of revolution and a load is larger than a predetermined value, and perform change-over into 4-cycle running by always closing a scavenging port at a lower portion of the cylinder by means of the valve (the rotational sleeve) at the lower portion of the cylinder and working the suction valve at the upper portion of the cylinder when a higher revolution than a predetermined number of revolution is given and an engine load is lighter than a predetermined load.

Abstract: A thermally insulated engine (1) includes a combustion chamber which has principal portions made of a thermally insulating material and a turbocharger (2) which has a compressor coupled to a turbine (21) for supercharging the engine (1). The thermally insulated engine comprises an electric motor (3) mounted on a rotatable shaft (22) of the turbine, a detecting unit (13, 14) for detecting an operating condition of the engine, an oxygenating mechanism (6) having an oxygenating film, a compressor mounted on the rotatable shaft (22) of the turbine for delivering oxygenated air from the oxygenating mechanism (6) to the engine, and a control unit (5) for controlling the electric motor to assist in operating the compressor and controlling the amount of oxygenated air depending on the operating condition of the engine as detected by the detecting unit. When the engine is accelerated, for example, the concentration of oxygen in the intake air is increased for suppressing NOx and soot in exhaust gases.

Abstract: A composite ceramic material includes a matrix of ceramic particles and particles of a different ceramic having a lower sintering temperature than that of the matrix ceramic, the particles of the different ceramic being dispersed in the matrix of ceramic particles. According to a method of manufacturing such a composite ceramic material, material particles of one of the elements of a matrix ceramic and particles of a disperse ceramic whose sintering temperature is lower than that of the matrix ceramic are mixed together, and the mixture is pressed into a preliminary shaped body. Then, the preliminary shaped body is placed in a sinter reaction furnace, and the particles in the preliminary shaped body are subjected to sinter reaction in the sinter reaction furnace, thereby producing a preliminary sintered body in which the particles of the lower sintering temperature are dispersed in the matrix ceramic which is generated by the sinter reaction.

Abstract: A slidable ceramic member includes a base of a sintered ceramic material which is a compound including silicon (Si) as a constituent element, the base having a sliding surface, and a coated layer covering the sliding surface of the base, the coated layer comprising a compound of elements, such as barium (Ba) and calcium (Ca), belonging to group IIa of the periodic table, silicon (Si), and oxygen (O). The slidable ceramic member is used as a slidable component of a heat engine such as a cylinder liner or a piston ring which is subjected to repeated thermal stresses. Such a slidable ceramic member is manufactured by placing powder of a fluoride including elements belonging to group IIa of the periodic table on a surface of a base, and heating the base while rubbing the powder against the surface of the base, whereby the silicon (Si) contained in the base and the group-IIa elements contained in the powder can react with each other, thereby forming a slidable layer on the surface of the base.

Abstract: An engine is selectively operable in two- and four-cycle modes by varying the timing to open and close intake and exhaust valves on the top of a cylinder.

Abstract: A magnetic plate is disposed in confronting relation to the shank end of an auxiliary exhaust valve which is opened to discharge exhaust gases from a combustion chamber. The magnetic plate is attracted by an electromagnet into abutment against the shank end of the auxiliary exhaust valve, and forces the auxiliary exhaust valve in an opening direction. When the auxiliary exhaust valve is opened, the exhaust gases are discharged from the combustion chamber, and the pressure in the combustion chamber is quickly lowered. Forces required to open a main exhaust valve subsequently may thus be reduced.

Abstract: A control system electromagnetically controls the operation of a valve which opens and closes an intake/exhaust port through which the interior and exterior of an engine cylinder communicate with each other. Since the timing with which the intake and exhaust valves are opened and closed cannot be altered during operation of the engine, the valve opening and closing timings are preset such that the engine operates with high efficiency when it rotates at a predetermined speed. When the engine is operating at a speed lower than the above predetermined speed, a air-fuel mixture which has once been drawn into the cylinder is discharged back out of the cylinder or discharged through the cylinder, resulting in a reduction in the efficiency and output power of the engine.

Abstract: An intake/exhaust valve actuator includes a movable permanent magnet coupled to the shank end of an intake/exhaust valve, a first fixed electromagnet having a plurality of fixed magnetic poles confronting a side of the movable permanent magnet, for opening and closing the intake/exhaust valve under an electromagnetic force developed between the movable permanent magnet and the fixed magnetic poles, a second fixed electromagnet having a fixed magnetic pole which confronts an end surface of the movable permanent magnet when the intake/exhaust valve is closed, the second fixed electromagnet having an excitation coil, an induction coil connected to the excitation coil of the second fixed electromagnet, for supplying electric energy to the excitation coil, a resonant circuit comprising a primary coil positioned in confronting relation to the induction coil and a capacitor connected to the primary coil, and control means for supplying electric energy to the resonant circuit when the intake/exhaust valve starts bein

Abstract: An electromagnetic valve actuating system opens and closes intake and exhaust valves of an engine under electromagnetic forces generated by an electromagnet. A reciprocally movable magnetic pole (6) is coupled to an intake/exhaust valve (9) An upper fixed magnetic pole (3a) confronts one end of the movable magnetic pole in the direction in which it is reciprocally movable. An intermediate fixed magnetic pole (3b) is disposed confronting the one end of the movable magnetic pole and the upper fixed magnetic pole. A lower fixed magnetic pole (3c) faces the other end of the movable magnetic pole. The intake/exhaust valve is opened and closed under electromagnetic attracting and repelling forces acting between the one end of the movable magnetic pole and the upper fixed magnetic pole. The timing to open and close the intake/exhaust valve can be varied when the timing to energize the magnetic poles is varied.

Abstract: A system for actuating a valve in stepped movement opens and closes intake and exhaust valves of an engine under electromagnetic forces generated by electromagnets. A magnetic body (3), which is reciprocally movable and has a plurality of tooth-like magnetic poles juxtaposed at equal intervals in the direction in which the magnetic body is reciprocally movable, is coupled to an intake/exhaust valve (8). A plurality of fixed magnetic poles (4c, 4d, 6c, 6d) are disposed in confronting relation to the tooth-like magnetic poles, the fixed magnetic poles being juxtaposed in the direction in which the magnetic body is reciprocally movable. The intake/exhaust valve (8) is opened and closed under electromagnetic attracting and repelling forces acting between the tooth-like magnetic poles and the fixed magnetic poles (4c, 4d, 6c, 6d). When the intake/exhaust valve (8) is opened and closed, the distance between the tooth-like magnetic poles and the fixed magnetic poles (4c, 4d, 6c, 6d) remains unchanged.

Abstract: A variable-cycle engine selectively operable in different cycle modes, includes a cylinder having a first intake port and an exhaust port which are defined in an upper portion thereof, and a second intake port defined in a lower portion thereof, a cylinder sleeve fitted in the cylinder and having a third intake port defined in a lower portion thereof, a sleeve valve circumferentially rotatably fitted over the cylinder sleeve, for selectively opening and closing the third intake port into and out of communication with the second intake port, the sleeve valve having an permanent magnet joined thereto, an actuator for rotating the sleeve valve under electromagnetic forces acting on the permanent magnet, and a turbocharger for supplying air under pressure to the first intake port and the second intake port. When the engine rotates at a low speed under a large load, the engine operates in a two-cycle mode of the uniform flow type.

Abstract: An electromagnetic valve actuating system opens and closes intake and exhaust valves of an engine under electromagnetic forces generated by an electromagnet. A reciprocally movable magnetic pole (8a) is coupled to the stem end of an intake/exhaust valve (8). An upper fixed permanent magnet (3) confronts one end of the movable magnetic pole (8a) the direction in which it is reciprocally movable. The intake/exhaust valve is opened and closed under attractive and repelling forces acting between the movable magnetic pole (8a) and the upper fixed permanent magnet (3). Since the polarity of the movable magnetic pole can be changed depending on how the first coil (5), the second coil (6), and the third coil (7) are energized, the timing to open and close the intake/exhaust valve (8) can be varied depending on the operating condition of the engine (1).

Abstract: An electromagnetic valve actuating system opens and closes intake and exhaust valves of an engine under electromagnetic forces generated by an electromagnet. A reciprocally movable permanent magnet (4) is coupled to an intake/exhaust valve (7). A first electromagnet (3) confronts one end of the movable permanent magnet (4) in the direction in which it is reciprocally movable. A second electromagnet (5) confronts the other end of the movable permanent magnet (4). The intake/exhaust valve (7) is opened and closed under electromagnetic attracting and repelling forces acting between the movable permanent magnet (4), the first electromagnet (3), and the second electromagnet (5). Since the forces to open and close the intake/exhaust valve (7) can be varied by varying the energized conditions of the first and second electromagnets (3), (5), the timing to open and close the intake/exhaust valve (7) can be varied depending on the operating condition of the engine (1).

Abstract: An electromagnetic valve actuating system opens and closes intake and exhaust valves of an engine under electromagnetic forces generated by an electromagnet. A reciprocally movable magnetic pole (6) is coupled to the stem end of an intake/exhaust valve (9). An upper fixed magnetic pole (3a) confronts one end of the movable magnetic pole (6) the direction in which it is reciprocally movable. An intermediate fixed magnetic pole (3b) is disposed in confronting relation to the one end of the movable magnetic pole (6) and the upper fixed magnetic pole (3a). A first fixed magnetic pole (3c) faces the other end of the movable magnetic pole (6). The intake/exhaust valve is opened under a repelling force acting between the upper fixed magnetic pole (3a) and the one end of the movable magnetic pole (6). A second distal fixed magnetic pole (3d) is coupled to the upper fixed magnetic pole (3a) and confronting the other end of the movable magnetic pole (6).

Abstract: An electromagnetic valve control system electromagnetically opens and closes intake and exhaust valves in an engine having a crankshaft. The electromagnetic valve control system has a valve actuator for opening an intake valve, a valve actuator for opening an exhaust valve, and a valve actuator for opening an auxiliary exhaust valve before the exhaust valve is opened.

Abstract: An electromagnetic valve actuating system opens and closes intake and exhaust valves of an engine under electromagnetic forces generated by an electromagnet. A reciprocally movable magnetic pole (6) in the form of an amorphous magnetic body is wound as multiple layers on an intake/exhaust valve (9). An upper fixed magnetic pole (3a) confronts one end of the movable magnetic pole (4), and a distal fixed magnetic pole (3c) confronts the other end of the movable magnetic pole. When the intake/exhaust valve (9) is to be driven in an opening direction, the movable magnetic pole (4) is attracted by the upper fixed magnetic pole (3a). When the intake/exhaust valve (9) is to be driven in a closing direction, the movable magnetic pole (4) is attracted by the distal fixed magnetic pole (3c). Since the movable magnetic pole (4) is light in weight, forces required to open and close the valve may be small, and the electromagnetic valve actuating system may be small in size.

Abstract: A valve electromagnetic force driving apparatus opens the suction/exhaust valve of an engine by an electromagnetic force generated by an electromagnet. A freely reciprocatable movable permanent magnet having at least one pair of magnetic poles arrayed in the direction of reciprocation is connected to the suction/exhaust valve, and fixed magnetic poles opposing the magnetic poles of the movable permanent magnet are provided and similarly arrayed in the direction of reciprocation. The suction/exhaust valve is driven, to open and close the same, by electromagnetic attractive and repulsive forces acting between the magnetic poles of the movable permanent magnet and the fixed magnetic poles. A fixed electromagnet opposing a reciprocating side end face of the suction/exhaust valve is provided and is adapted to subject the valve to a force acting in the opening direction when the valve is opened and closed.