Abstract: A poppet valve moves up and down in a valve operating mechanism in an internal combustion engine. A cylindrical fixed electrode is fixed to a support plate on a cylinder head, and a cylindrical moving electrode is mounted to the lower surface of a valve spring retainer which is mounted to the poppet valve via a cotter. The fixed electrode is connected to a circuit which comprises a variable condenser and a resistance. The valve moves up and down during firing operation of the engine. Thus, variation in electrostatic capacity is detected by the two electrodes, transmitted to a circuit via a lead mounted to the fixed electrode, and converted to a voltage by the circuit, thereby detecting valve position exactly.

Abstract: A valve spring retainer is mounted to the upper end of a poppet valve via a pair of cotters in an internal combustion engine of an automobile. The valve spring retainer has an intermediate portion and an outer flange which is engaged with the upper end of a valve spring. The lower surface has a gap between the outer flange and the intermediate portion to decrease wear which is caused by engagement with the valve spring. There is also provided a valve operating mechanism which has a valve spring retainer which has a projection on the lower surface so as to prevent wear.

Abstract: In a valve head of a poppet valve used in an internal combustion engine, a lobe is formed. The lobe has a vertical section of an isosceles triangle which has a vertex in the middle. By pressing the lobe in a bore of a die, the lobe is plastically deformed, so that a valve face is formed at a position which contacts a valve seat. Suitable airtightness is obtained between the valve face and the valve seat.

Abstract: A valve spring retainer is mounted to the upper end of a poppet valve via a pair of cotters in an internal combustion engine of an automobile. The valve spring retainer has an intermediate portion and an outer flange which is engaged with the upper end of a valve spring. The lower surface of the outer flange is radially and inclined towards the valve spring to decrease wear which is caused by engagement with the valve spring. There is also provided a valve operating mechanism which has a valve spring retainer which has a projection on the lower surface so as to prevent wear.

Abstract: A method of manufacturing and Al alloy tappet, used in an internal combustion engine, includes supplying wear resistant particles on a surface of a light metal tappet body, the surface slideably contacting a cam, kneading said particles with a surface layer of the surface of the tappet body to imbed them and then changing the surface layer after kneading to a flat surface.

Abstract: An Al alloy poppet valve is used in an internal combustion engine and has a valve head and a valve stem. At least the valve head is made of non-heat-treatable Al alloy in which ceramic particles such as oxide and carbide are uniformly dispersed, thereby increasing wear resistance and durability.

Abstract: A poppet valve in an internal combustion engine of a vehicle consists of a valve body which comprises a valve stem and a valve head at one end of the valve stem. An oxidized layer is formed on portions of the valve body which contacts another valve-operating member. On the oxidized layer, a carburized layer is formed to cover the whole surface to increase wear resistance and fatigue strength of the valve.

Abstract: An Al alloy poppet valve is used in an internal combustion engine. The poppet valve comprises a valve stem and a valve head at the end of the valve stem. The valve head has a tapered valve face, which is engaged on a valve seat when an inlet port is closed by the poppet valve. The valve face has a thermal hardened layer on the surface and an inner alloy layer, thereby increasing mechanical strength to provide high durability and reliability.

Abstract: A tappet is used in an internal combustion engine. A cam-slidably-contacting member is placed on a top wall of a tappet body via diffusing material that includes a mixture of one or more elements of Zn, Mg, Sn, Cu and Pb. The cam-slidably-contacting member and the tappet body are pressed with the diffusing material held therebetween, so that the diffusing material is diffused into the tappet body and the cam-slidably-contacting member until the layer of the diffusing material does not substantially remain, and a tappet of high strength is formed.

Abstract: A tappet made of light metal comprises a ceiled cylindrical tappet body made of light metal, and a cam receiving plate made of hard metal which has the same outer diameter as that of the tappet body, and which is provided at its outer peripheral edge with a sharp annular piece, the cam receiving plate being integrally coupled to the tappet body by causing the annular piece to bite into the top surface and welding the annular piece and the top surface. With this structure, the tappet body and the cam receiving plate made of different materials can be bonded strongly.

Abstract: A valve spring is used in a valve operating mechanism for moving a poppet valve up and down in an internal combustion engine of an automobile. The terminal end of the uppermost portion of the valve spring extends in a tangential direction to go away from an axis of the valve spring, thereby avoiding contact with a retainer to prevent wear.

Abstract: A poppet valve which has a valve stem is moved up and down to open and close a valve port in an internal combustion engine of a vehicle such as an automobile. A moving coil is wound on a bobbin mounted to the valve stem, and a magnet is mounted to a yoke fixed to a cylinder head. A plurality of sensors detect working conditions of the engine to send a signal to a working condition discriminating portion of CPU. The signal is further sent to a valve timing lift pattern memory in which optimum valve timing and lift are set corresponding to the working conditions to generate an optimum valve position signal. In the meantime, an actual position of the valve is detected by a sensor on the yoke to send an actual valve position signal to a valve position detector.

Abstract: A poppet valve is provided to open and close a valve seat in an internal combustion engine. At the end of a valve stem of the valve, a cylindrical support is fixed, and on the outer circumferential surface of the support, a moving coil is wound. There is formed an annular cavity in a yoke fixed to a bracket fixed on a cylinder head, and a permanent magnet is fixed in the annular cavity of the yoke. Between the permanent magnet and the yoke in the annular cavity, the support which has the moving coil is inserted. By a control system having CPU, an electric current is applied to the moving coil, thereby providing optimum valve timing and lift to decrease seating noise and improving engine performance.

Abstract: A tappet made of Al alloy is used in a valve operating mechanism of an internal combustion engine of a vehicle. On the whole outer circumferential surface of the tappet, a helical projection and a helical groove are formed alternately to form an uneven surface. A plurality of uneven surfaces are formed on a ridge of the projection at regular intervals. The outer circumferential surface is coated with a wear resistant Fe film by thermal spraying. The uneven surfaces on the projection provide high adhesion strength of the film to the outer circumferential surface of the tappet to improve peel resistance, thereby increasing durability and reliability of the Al alloy tappet.

Abstract: A tappet is used in an internal combustion engine. A cam-slidably-contacting member is placed on a top wall of a tappet body via diffusing material which comprises mixture of one or more elements of Zn, Mg, Sn, Cu and Pb. The cam-slidably-contacting member and the tappet body are pressed with the diffusing material held therebetween, so that the diffusing material is diffused into the tappet body and the cam-slidably-contacting member until a layer which comprises only the diffusing material does not substantially remain to form the tappet having high strength.

Abstract: The lower surface of a valve spring retainer is engaged on a valve spring in a valve operating mechanism of an internal combustion engine. The valve spring retainer is subjected to T6 treatment under JIS (Japanese Industrial Standard), and machined as finishing. The lower surface of the valve spring retainer is not machined, and remains as subjected to T6 treatment, thereby improving fatigue strength and wear resistance.

Abstract: A soldering layer is formed on a valve guide or valve seat and/or a holding bore of a cylinder head in an internal combustion engine. The solder can be melted below the highest temperature which the valve guide or valve seat reaches during operation of the internal combustion engine. The valve guide or valve seat is a press fit in the holding bore of the cylinder head, and with operation of the internal combustion engine, the soldering layer is melted to close gaps on the contacting surfaces between the holding bore and valve guide or valve seat. The soldering layer finally has a higher melting point than the highest temperature of the valve guide or valve seat as above. During operation of the engine, the soldering layer is not melted.

Abstract: A valve spring is used in a valve operating mechanism for moving a poppet valve up and down in an internal combustion engine of an automobile. The terminal end of the uppermost portion of the valve spring extends in a tangential direction to go away from an axis of the valve spring, thereby avoiding contact with a retainer to prevent wear.

Abstract: A tappet made of Al alloy is used in a valve operating mechanism of an internal combustion engine of a vehicle. On the whole outer circumferential surface of the tappet, a helical projection and a helical groove are formed alternately to form an uneven surface. A plurality of uneven surfaces are formed on a ridge of the projection at regular intervals. The outer circumferential surface is coated with a wear resistant Fe film by thermal spraying. The uneven surfaces on the projection provide high adhesion strength of the film to the outer circumferential surface of the tappet to improve peel resistance, thereby increasing durability and reliability of the Al alloy tappet.

Abstract: A poppet valve in an internal combustion engine comprises a valve head and a valve stem. On a valve face of the valve head, a hardened layer of dendrites in which crystals are directed from the inside to the surface is formed, thereby increasing wear resistance of the valve face without cladding.