Abstract: A valve operating device for the intake or exhaust valves of a multicylinder internal combustion engine. Each cylinder has a valve operating mechanism associated therewith for opening and closing intake or exhaust valves associated with that cylinder in at least two different manners for different engine speeds. The cylinders are divided into two or more groups with each of said valve operating mechanisms being arranged to operate the intake or exhaust valves associated with the cylinders in one of the groups in a different operation mode from the intake or exhaust valves associated with the cylinders in another of the groups, at least under a certain operating condition of the engine, such as at low speed. The various embodiments disclosed different arrangements for the valve operating mechanisms for improving engine operation over various ranges of engine speed.

Abstract: Valve operating apparatus for an internal combustion engine is described in which the cam follower surface on the valve operating rocker arms is defined by the external surface of a cylindrical body mounted for rotation on the rocker arm, whereby the cam follower surface is in rolling contact with the associated cam to reduce friction losses in the apparatus and wear of the apparatus components.

Abstract: Valve operating apparatus for an internal combustion engine in which plural intake valves and exhaust valves are associated with each cylinder. The respective valves are operated in one engine-operating condition in response to the action of a first set of cams and in another engine-operating condition in response to the action of a second set of cams coupled to the first cam set. The cams operating the intake valves impart a different valve operating action than those operating the exhaust valves.

Abstract: A valve operating device for an internal combustion engine having a drive rocker arm operatively associated with an intake or exhaust valve and a free rocker arm releasable from the intake or exhaust valve. The drive rocker arm and the free rocker arm are disposed adjacent to each other and operable selectively in mutually different modes according to the rotation of the camshaft. In one embodiment either the drive or free rocker arm has two arms connected together with one arm on each side of the other rocker arm for balanced loading. A selective coupling mechanism is disposed between the drive rocker arm and the free rocker arm for selectively connecting and disconnecting them with a coupling pin movable in a direction substantially normal to the axis of the rocker shaft.

Abstract: A light, compact angle-of-rotation sensor is provided that is comprised of a magnetic ring bonded to a shaft by means of resin. The magnetic ring is provided around its periphery with a number of magnetized zones, with each such magnetized zone having a different number of magnetic poles, and magnetic interference between magnetized zones is prevented by leaving non-magnetized spaces between the magnetized zones. The prevention of magnetic interference can be further enhanced by the provision of non-magnetized portions between the magnetic poles of the magnetized zones.

Abstract: A light, compact angle-of-rotation sensor is comprised of a magnetic ring within which resin is used to fix the ring to the periphery of a shaft. Formed on the magnetic ring are insets into which the resin enters, providing a strong bond between the resin and the magnetic ring. In addition, a key inset into the shaft provides a strong bond between the resin and the shaft. Magnetized zones are formed on the outer surface of the magnetic ring, and magneto electric transducer means are arranged in the proximity of these zones to face said zones, and the angle of rotation is detected from the changes in magnetism that accompany the rotation.

Abstract: A valve operating mechanism for an internal combustion engine having cams rotatable in synchronism with a crankshaft, a pair of valves disposed in intake or exhaust ports of a combustion chamber, and four pivotable rocker arms for transmitting the lifting motion of said cams to said valves. Four cams are provided with different cam profiles corresponding to respective ranges of rotational speeds of the engine. Switching means are operated by hydraulic oil pressure for selectively connecting and disconnecting the rocker arms to thereby operate the valves in several different modes for different engine speeds.

Abstract: A method of manufacturing an angle-of-rotation sensor comprises fabricating a rotating member by providing a shaft coaxially inside a magnetic ring made of ferrite magnetic material or the like, and filling the space between shaft and ring with resin. As the resin is first provided on the outer surface of the magnetic ring, then in the interior, a balance is achieved between tensile stress from within the ring and compressive stress from the outside of the ring, and as a result the ring is not broken or cracked. Thus, with this method it is possible to make the angle-of-rotation sensor small and light.

Abstract: A hydraulic circuit for a valve operation timing control device for supplying oil pressure through an oil passage defined in a rocker shaft to an actuator disposed in rocker arms which are pivotally supported on the rocker shaft for transmitting lifting motion from cams rotating in synchronism with the crankshaft of an engine to valves disposed in intake or exhaust ports of a combustion chamber. A solenoid-operated valve and flows restricting orifice are provided between the oil pump and oil passage for causing oil flow to the oil passage for lubrication even when the oil is cold and the actuator is not operated.

Abstract: Valve operating apparatus is disclosed in which the valves are operated by rocker arms driven by cams having different cam profiles and hydraulically operated coupling mechanisms for selectively connecting or disconnecting adjacent rocker arms to vary the operation of the valves under different engine operating conditions. The coupling mechanisms are operated by fluid supplied through the rocker shaft mounting the rocker arms. The rocker shaft is divided into independent fluid supply passages whereby the couplings can be suppplied independently with operating fluid in order to expand the number of available valve operating control modes. Variations are described in which operating fluid can be independently supplied to various ancillary hydraulically-operated equipment, as well as to the selective coupling mechanisms.

Abstract: Valve operating apparatus is disclosed in which intake or exhaust valves of an internal combustion engine are operated by rocker arms driven by cams having different cam profiles and hydraulically operated coupling mechanisms for selectively connecting or disconnecting adjacent rocker arms to vary the operation of the valves under different engine operating conditions. Sensing means in the form of a piston displacement detecting device is included in the apparatus to monitor its operating condition.