Abstract: In a decompression braking apparatus which is applicable to a Diesel engine and is capable of switching an engine braking condition so as to achieve an engine revolution speed area when a decompression braking request is issued, a sleeve portion of an eccentric bushing member is pivotally interposed between an inner periphery of a rocker arm and an outer periphery of a rocker shaft fitted into the rocker arm so as to be enabled to displace a swing center of the rocker arm toward a downward direction aligned with an open direction of an exhaust valve whose degree of openings in a closure stroke thereof is varied, a first actuator is so constructed and arranged as to actuate the eccentric bushing member to be pivoted so that the swing center of the rocker arm is displaced to a second position at which the degree of openings of the exhaust valve in the closure stroke is relatively large and a second actuator is so constructed and arranged as to limit the pivotal movement of the eccentric bushing member according

Abstract: A variable cam phaser (VCP) is disclosed in various modifications. The VCP includes a piston responsive to pressure in a fluid chamber having an inlet orifice and a plurality of outlets including a first outlet and a plurality of second outlets. A valve slide is movable to cover said second outlets one after another to pressurize the fluid chamber to displace the piston against a return spring. Outer and inner splined slides are drivingly mated with an internal helical spline of a cylindrical body secured to a sprocket and an external helical spline of a stub shaft secured to a camshaft. The splined slides are disposed between the piston and the return spring. Thus, movement of the piston and splined slides assembly in response to pressurization or depressurization of the fluid chamber advances or retards the valve timing or phase angle of the camshaft relative to the sprocket.

Abstract: A valve timing control system for an internal combustion engine includes a hollow sprocket rotatably supported on a camshaft, and a rotary member housed within the sprocket and rigidly connected to the camshaft for rotation therewith. The rotary member has a pair of radially extending portions, on which a pair of gears are rotatably supported. The sprocket has an internal toothed circumference which is engageable with the gears to cause the gears to rotate in accordance with rotation of the sprocket for causing relative angular displacement of the rotary member to the sprocket. The valve timing control system further includes a pair of stopper pins for regulating relative angular displacement of the intermediate rotary member to the sprocket within a predetermined maximum range, and a clutch mechanism for restricting rotation of the gears.

Abstract: An intake- and/or exhaust-valve timing control system for internal combustion engines comprises a timing pulley including inner and outer gears, a camshaft including an outer gear and a ring gear disposed between the pulley and the camshaft for varying the phase angle between the camshaft and the pulley. The ring gear includes inner and outer gears respectively meshed with the outer gear of the camshaft and the inner gear of the pulley. At least one of the two meshing pairs of gears is helical. The outer gear of the pulley has a first number of teeth and the outer gear of the camshaft or the ring gear has a second number of teeth different from the first number, and a combination of the first and second numbers is selected in such a manner as to satisfy an inequaltiy .vertline.dO+n(360.degree./M).vertline..ltoreq..vertline.T.vertline.

Abstract: An electronic noise attenuation system for attenuating a sound wave propagated from a source of noise by generating another sound wave 180.degree. out of phase and having the same sound pressure with the propagated sound wave from electro-mechanic transducer means disposed in a propagation passage of sound waves. In the electronic noise attenuation system, a drive signal for drive the electro-mechanic transducer means is generated in accordance with output signals respectively output from upstream-side and downstream-side mechano-electric transducer means respectively disposed in the propagation passage with the electro-mechanic transducer means therebetween. Namely, the drive signal is created by performing an operation on a difference signal between the output signal of the upstream mechano-electric transducer means and the drive signal according to a given transfer function.

Abstract: An intake- and/or exhaust-valve timing control system for internal combustion engines in which a ring gear mechanism is provided between a timing pulley and a cam shaft for adjusting the phase angle between the pulley and the cam shaft. A drive mechanism is also provided for driving the ring gear mechanism depending upon the operating state of the engine. The drive mechanism includes a hydraulic circuit having oil supply and exhaust passages, a flow control valve having a spool valve for controlling the amount of working fluid flowing through the hydraulic circuit, a controller for monitoring the operating state of the engine, and an electromagnetic actuator having a plunger rod for actuating the flow control valve in response to the control signal from the controller. The flow control valve and the actuator are integrally mounted in the cylinder head. Therefore, relative friction between the facing ends of the spool valve and the plunger rod is avoided.

Abstract: An intake- and/or exhaust-valve timing control system for an internal combustion engine comprises an inner sleeve having an outer toothed portion, firmly connected to a front end of a camshaft, a cam sprocket having an inner toothed portion, connected through a timing chain to an engine crankshaft, and a ring gear mechanism including inner and outer toothed portions respectively meshing with the outer toothed portion of the sleeve and the inner toothed portion of the cam sprocket, for changing the intake and/or exhaust-valve timing of the engine.

Abstract: A valve timing control system includes a valve timing control mechanism constructed independently of the camshaft with avoiding direct engagement between a timing adjusting element and the camshaft. For enabling this, an inner cylinder is provided as an additional component. The inner cylinder is provided with an external gear teeth engaging with the internal gear teeth of a timing adjusting element. The inner cylinder is designed to be firmly secured to the camshaft by means of an axial fastening bolt. Such construction permits advance adjustment of phase relationship between the sprocket and the inner cylinder before fixing the inner cylinder on the camshaft.

Abstract: A valve timing adjusting mechanism houses a timing adjusting gear assembly within a liquid-tight housing which prevents working fluid used to adjust the timing from coating a timing gear engaging a timing belt. The working fluid is introduced within the housing to exert timing adjusting force on the timing adjusting mechanism, resulting in relative angular displacement between a camshaft and the timing gear which is manifested as an adjustment to the valve timing. With this arrangment, the timing belt is free of working fluid. Therefore, the lifetime of the belt retains its design value and slip between the timing belt and the timing gear can be prevented.