A hydraulic type scissors gear may include a first gear having a working chamber formed therein and oil supplied into the working chamber; a second gear provided to be relatively rotatable coaxially with a side surface of the first gear; and a piston supplied with the oil supplied into the working chamber, and moved in the working chamber by pressure of the oil supplied thereinto to apply a force that pushes the second gear in a rotation direction opposite to a rotation direction of the first gear to rotate the second gear.

A gearbox comprising an input shaft fixed with a first gear, an output shaft fixed with a second gear, and a rim gear without a web or hub rotatably mounted on a shaft having a hollow space. A lubrication line extends from within the shaft to a lubrication space disposed between an inner surface of the rim gear and an outer surface of the shaft. The rim gear is held in place on the shaft by a first interior surface of a first chamber member and a second interior surface of a second chamber member.

A valve timing adjustment device includes: a first rotatable body that is rotated about a rotational axis synchronously with one of a drive shaft and a driven shaft of an engine; and a second rotatable body that is rotated about the rotational axis synchronously with the other one of the drive shaft and the driven shaft. The first rotatable body includes: a fastening portion, a slide portion and a bearing portion. The fastening portion is fastened to the one of the drive shaft and the driven shaft. The bearing portion includes an outer peripheral surface that is opposed to an inner peripheral surface of the second rotatable body, and the bearing portion rotatably supports the second rotatable body. The fastening portion projects on one axial side of the slide portion and the bearing portion in an axial direction toward the one of the drive shaft and the driven shaft.

A tubular roller valve for an internal combustion engine, which includes a hollow tube having at least one hole, the at least one hole being configured to access an air inlet or an exhaust of a cylinder in an engine block, a tubular outer insulator outside of the hollow tube, the outer insulator being fixed to a cylinder head, and a tubular inner insulator inside of the hollow tube. An additional tube between the hollow tube and the outer insulator can serve to operate as a compression release brake.

A method for attaching a gear driving part of this disclosure includes a first step of inserting a positioning bolt (23) into a positioning hole (21) of a first gear from a front side, and then screwing the positioning bolt into a screw hole (24) of a fixation-side member to regulate a phase of the first gear with respect to the fixation-side member; and a second step of inserting a portion of the bolt protruding to a front side of the first gear into a hole (22) of the gear case, and meshing the first gear with the second gear while positioning the fixation-side member in a predetermined phase position of the gear case.

A variable valve operating device for an internal combustion engine includes a cam carrier supported on a camshaft and shifting switching pins that are advanced into and retracted out of shift lead grooves defined in the cam carrier. The shift lead grooves include shift groove side walls having shift groove side wall surfaces from shift starting inflection regions of the cam carrier to shift ending inflection regions thereof. The shift groove side walls include particular shift groove side walls extending from axial positions of the shift starting inflection regions toward shift intermediate regions and also extending from circumferential positions of the shift intermediate regions disposed between the shift starting inflection regions and the shift ending inflection regions toward the shift starting inflection regions. The side walls have slanted outer circumferential surfaces extending from the circumferential positions progressively deeper toward groove bottom surfaces and reaching the shift starting inflection regions.

An internal combustion engine is provided with a variable valve operating apparatus, for use on a saddle-type vehicle. When a switching drive shaft is longitudinally moved under hydraulic pressure switched by a solenoid valve, a cam mechanism advances and retracts a switching pin. When the switching pin is advanced to engage in a lead groove in a cam carrier, the cam carrier is axially moved while rotating, to switch cam lobes to act on an engine valve. A solenoid valve is disposed on a left or right end in the leftward and rightward directions across the vehicle width, of a front or rear surface of a cylinder head. The solenoid valve is placed in an appropriate location in the cylinder head out of interference with other parts of the engine, thereby making the vehicle small in size.

A system and method is provided for converting wellhead pressure of natural gas wells, or for converting water head pressure of water towers, to rotational power for operating rotated equipment, such as electrical generators, electrical alternators, pumps, air compressors, and other rotated equipment.

A variable camshaft timing system for an internal combustion engine with an idler shaft mounted camshaft phaser is provided. The camshaft phaser includes a driven wheel that is driven by the crankshaft, a driving wheel that drives the camshaft, and a hydraulically driven phasing assembly therebetween. A valve body is connected to the idler shaft for directing the flow of pressurized hydraulic medium to the camshaft phaser. The valve body includes a center part with an integral retainer for holding the camshaft phaser on the idler shaft, and a radial extension integrally connected to the center part that extends radially outwardly from an axis of the idler shaft a predefined distance. A control valve receiving part is integrally connected to radial extension and includes a control valve bore. A control valve is located in the control valve bore in the valve body. The control valve extends through the engine cover at a desired location for control valve maintenance.

A valve drive for an internal combustion engine has a first camshaft which is rotatably mounted in a first and a second camshaft bearing and which includes at least one cam with a first cam curve and a second cam curve that differs from the first cam curve, wherein a gas exchange valve can be actuated by the first or the second cam curve. A camshaft section is provided, by which the cam can be moved by an actuator such that the gas exchange valve can be actuated either via the first or the second cam curve. The first camshaft and the cam have a fixed position relative to each other. The first camshaft can be axially moved in the first and the second camshaft bearing.