Abstract: A high temperature air heater including a heat transfer conduit located in higher temperature gas. The heat transfer conduit is made up of a heat transfer pipe through which the air to be heated flows and a refractory protective pipe covering the heat transfer pipe. A clearance is provided between the heat transfer pipe and the refractory protective pipe. The clearance makes it possible to accommodate the differences in thermal expansion between the heat transfer pipe and the refractory protective pipe to prevent damaging the refractory protective pipe, thus extending the service life of the high temperature air heater.

Abstract: In an air heater for use in recovering, by heat exchange, the heat of an exhaust gas generated from an incinerator for disposing of wastes, prolonged service life and improved working efficiency are attainable with least thermal deformation. The air heater has a heat transfer conduit which is placed in high temperature highly corrosive gas.

Abstract: In an apparatus for heating high-temperature air for use in recovering, by heat exchange, the heat of an exhaust gas of elevated temperature generated from an apparatus for disposing of wastes, prolonged service life, improved working efficiency, improved efficiency of heat recovery on heat exchange are attainable with least thermal deformation and reduced dust deposition.

Abstract: Wear resisting steel, a sliding member for a cylinder in an internal combustion engine, and a ring spring consist of: carbon: equal to or less than 2.2% by weight; silicon: equal to or less than 1.2% by weight; manganese: equal to or more than 0.2 % by weight and less than 1.20% by weight; chromium: equal to or less than 16% by weight; phosphorus: equal to or less than 0.08% by weight; sulfur: equal to or more than 0.15% by weight; other compositions: equal to or less than 2.0 % by weiht; and the balance substantially consisting of iron. The surfaces thereof may be sulphurized. The steel has excellent resistance to wear and scuffing, provides high strength, great elongation, and high toughness, and also provides good machinability.

Abstract: A vibration-damping alloy having excellent vibration-damping properties, high strength, and excellent workability and weldability has the composition defined by a triangle formed by connecting points A (89% by weight of M, 0.2% by weight of Ni, and 10.8% by weight of Mn), B (75% by weight of M, 15% by weight of Ni, and 10% by weight of Mn), and C (75% by weight of M, 0.2% by weight of Ni, and 24.8% by weight of Mn) in a triangular diagram showing the proportions of M, Ni and Mn in FIG. 1. M consists of Fe and Si, Fe and P, Fe and Al, Fe, Nb and C, Fe and Cu, Fe, Mo and C, or Fe, Ti and C.

Abstract: A knocking sensor comprises a casing for receiving a pickup assembly including a transducer, which produces an electrical signal in accordance with engine vibrations, and a connector having at least a single pin electrically connected to the transducer. The casing comprises a threaded projection to be screwed in a screw hole of an engine, and a nut-like periphery to be rotated by a tool. The knocking sensor can be attached to the engine by means of an impact wrench, by rotating the nut-like portion. A plug connected to one end of a shielding code can be plugged in the connector to make an electrical connection between the transducer and a signal processing circuit after the knocking sensor has been attached to the engine, and therefore, the shielding code is prevented from being damaged during installation of the knocking sensor. The use of an impact wrench ensures secure attachment of the sensor, and reduces the installation time.

Abstract: A piezoelectric ceramic vibrator is mounted inside a metal case including a portion adapted for fastening the case to an engine, and the vibrator is adapted to resonate in response to a vibration frequency produced upon knocking of the engine. The output of the vibrator is taken out as a knock output.

Abstract: A knock sensor includes a metal case of a shape that can be easily mounted to an engine, a base of a size that can be fitted in the case and having preliminarily mounted thereon a knock detecting ceramic vibrator, and a cover adapted to be fitted in the case so as to hold the base in place when fitted in the case.

Abstract: An electromagnetic transducer in which a D.C. magnetic flux generating section including a permanent magnet and a signal flux generating section including a coil are arranged in spaced relation on opposite sides of a diaphragm to form a balanced type transducer.