Abstract: A valve drive system of an internal combustion engine provided with a camshaft (20) adapted to be rotated by means of a crankshaft, a cam robe (38) rotatably mounted on the camshaft (20), a cam (24) formed integrally with the cam robe (38) and serving to open and close an intake valve (24) in cooperation with a valve spring (92), a viscous coupling (40) arranged between the camshaft (20) and the cam robe (38) and serving to transmit a rotatory force of the camshaft (20) to the cam robe (38), and a spiral spring (42) for connecting the camshaft (20) and the cam robe (38) and urging the cam robe (38) toward a predetermined rotational angle position with respect to the camshaft (20) .

Abstract: A valve system is provided for driving engine valves arranged in an internal combustion engine. The valve system comprises a valve drive arm member pivotally supported on a side of a main body of an engine while being maintained in contact with end portions of the engine valves, a first rocker arm for rocking the valve drive arm member, a second rocker arm for causing the valve drive arm member to undergo rocking at an amplitude greater than rocking by the first rocker arm, and coil springs for urging the engine valves in closing directions, respectively. Each coil spring is interposed between a retainer disposed fixedly on the corresponding engine valve and a cylinder head. Each coil spring is designed to avoid interference with a rocking path of the corresponding rocker arm on a side of the coil spring.

Abstract: In a valve-moving apparatus for an internal combustion engine, lever members are integrally formed with rocker shaft parts and arm parts, the lever members are provided with large-diameter parts larger in diameter than support parts, disposed between support parts of the rocker shaft parts supported by support members of the engine and the arm parts; rocker arms driven by cams are rotatably supported on the large-diameter parts; and change-over mechanisms for selectively engaging the large-diameter parts and the rocker arms are disposed in the large-diameter parts, thereby improving rigidity of the large-diameter parts and achieving improved reliability of the change-over mechanisms.

Abstract: An internal combustion engine of the present invention comprises at least first and second cylinder banks each including a plurality of cylinders or a single cylinder, a first valve operating mechanism provided for each of the cylinders of the first cylinder bank for operating an intake valve or an exhaust valve of the cylinder to open and close, and a second valve operating mechanism having a valve operating characteristic different from that of the first valve operating mechanism and provided for each of the cylinders of the second cylinder bank for operating an intake valve or an exhaust valve of the cylinder to open and close.

Abstract: In a valve-moving apparatus for an internal combustion engine, lever members are integrally formed with rocker shaft parts and arm parts, the lever members are provided with large-diameter parts larger in diameter than support parts, disposed between support parts of the rocker shaft parts supported by support members of the engine and the arm parts; rocker arms driven by cams are rotatably supported on the large-diameter parts; and change-over mechanisms for selectively engaging the large-diameter parts and the rocker arms are disposed in the large-diameter parts, thereby improving rigidity of the large-diameter parts and achieving improved reliability of the change-over mechanisms.

Abstract: The valve operating system structure with a variable valve timing mechanism of the invention comprises an intake valve or an exhaust valve provided for an engine, a low speed cam having a cam profile for a low speed valve timing and rotatable in response to rotation of a crankshaft of the engine, a high speed cam having a cam profile for a high speed valve timing and rotatable in response to rotation of the crankshaft, a main rocker arm for contacting with the low speed cam so as to be operated by the low speed cam, a sub rocker arm for contacting with the high speed cam so as to be operated by the high speed cam, mode change-over means for changing over the mode of the sub rocker arm between a non-interlocking mode in which the sub rocker arm is not interlocked with the main rocker arm and an interlocking mode in which the sub rocker arm is interlocked with the main rocker arm, a swing arm supported for pivotal motion and for adjustment in phase relative to the main rocker arm and having a valve contacting p

Abstract: A method for treating the surface of a titanium alloy comprising a pretreatment process for cleaning a workpiece to be treated comprising a titanium alloy with an acid, a heating process for heating the pretreated workpiece in an oxidative atmosphere for a predetermined period of time to form a composite layer comprising oxide layers and oxygen-enriched layers on the surface of the workpiece, and a descaling process for rapidly quenching the treated workpiece to remove a scale layer formed as an outermost layer of the composite layer on the surface of the workpiece; or, without the pretreatment process, comprising the heating process, the descaling process, and an aging process for aging by maintaining the workpiece at a predetermined temperature; or, comprising the pretreatment process, the heating process, the descaling process, and the aging process, thereby adequately improving the abrasion resistance and burning resistance of the workpiece and preventing an increase in abrasion of a partner part sliding

Abstract: A power transmission system transmits rotative power from a driver pulley to a driven pulley through a toothed belt. The tooth tips (27b) and/or tooth bottoms (27c) of teeth of at least the driven pulley (10) lie in a plane including a central axis l.sub.2 of rotation of the driven pulley and are inclined with respect to the central axis l.sub.2. When the toothed belt (14) is operated to transmit the rotative power, the position where teeth of the pulley (10) and teeth of the toothed belt (14) start meshing with each other is progressively displaced, thus lowering the level of impact sounds produced when the teeth mesh with each other.

Abstract: Disclosed herein is a roller rocker arm comprising a rocker arm body having a rocking center hole through which a rocker shaft is inserted and adapted to be rockably supported to the rocker shaft; a pair of forked projections projecting from the rocker arm body in a direction perpendicular to a tangent of a circle about a rocking center axis of the rocker arm body; a pair of pin holes formed through the pair of forked projections; a hollow roller pin inserted into the pair of pin holes and fixed between the pair of forked projections; a cam follower roller through which the roller pin is inserted; a plurality of needle rollers interposed between the cam follower roller and the roller pin for rotatably supporting the cam follower roller to the roller pin in such a manner as to extend in parallel one another in a longitudinal direction of the roller pin; a pair of disk-like spacers rotatably supported to the roller pin and interposed between ends of the needle rollers and the projections; and an adjuster mounte

Abstract: A jet-stream control combustion engine comprising an auxiliary intake system in a cylinder head leading to an internal combustion chamber, besides an intake system and an exhaust system. The auxiliary intake system is equipped with a hollow cylindrical jet piece fitted into a through-hole from the combustion chamber side, a hollow cylindrical jet body fitted from the opposite side of the through-hole, and an auxiliary intake passage opened and closed by a jet valve fitted inside of the jet body, wherein the auxiliary intake passage communicates with the internal combustion chamber via an injection chamber formed in the jet piece and an injection port thereof. The jet piece and the jet body are screwed and fixed relative each other in such a way as to compressibly contact with receiving surfaces of the cylinder head, so that the structure gets simplified and facilitates to assembly and disassembly with high parts-interchangeability.