Abstract:
A valve timing gear of an internal-combustion engine is provided, in the case of which a camshaft acts by a timing cam upon a valve by way of a tappet whose cam-side contact path can be changed by a control device for changing the valve opening period. For achieving a small-sized control device, this control device comprises a slider rocker guided in the valve lifting direction by way of a first sliding hinge joint arranged on an engine section side and an additional sliding hinge joint provided on the tilting segment side, with a control opening penetrated with play by a timing-cam-free section of the camshaft. An element, which can be operated in a controlled manner, of an adjusting device is arranged in/on the camshaft, while rotating with it, and being applied such to the circumference of the control opening that the adjustable slider rocker, while the camshaft is rotating, carries out for each valve lift a periodic rocking movement which is used for forcibly controlling the tilting segment.
Abstract:
A variable valve mechanism using a non-uniform coupling in an internal combustion engine is equipped with an axis-supporting member for supporting a cam-side rotation axis in an eccentric state. In the variable valve mechanism, the axis-supporting member is driven while taking account of friction occurring in the axis-supporting member by changing the position of the axis-supporting member so as to align with the direction of a dragging torque generated between the axis-supporting member and an intermediate rotating member or between the axis-supporting member and a rotation axis member.
Abstract:
A valve gear mechanism for an internal combustion engine includes a variable valve control mechanism comprising a shaft (1) having an axis of rotation (D) and serving to transmit the rotary motion to the valve gear mechanism; a rotating body (10) being rotatably supported on said shaft (1); and an intermediate member (20) surrounding said shaft (1) and being disposed adjacent to said rotatable rotating body (10) in an axial direction and being rotatable with respect to said shaft (1) and having a drive connection to said shaft (1) via a first sliding guide (15) and a first transmission element (40, 50) and to said rotating body (10) via a second sliding guide (16) and a second transmission element (70), wherein said first transmission element (40, 50) comprises a radial pin (40) being inserted in said shaft (1) in a direction substantially vertical to said axis of rotation (D). The radial pin (40) is preferably held so as to be displaceable in a recess (51) of a sliding block (50) which is pivotably mounted in a bearing seat (22) in said intermediate member (20).
Abstract:
In an apparatus for detecting a valve lifting characteristic of a cam shaft assembly for use in a multi-cylinder internal combustion engine with a cylinder head to control opening and closure of cylinder valves, a sensor which is so arranged and constructed as to detect the valve lifting characteristic of the cam shaft assembly is disposed on an end of at least one of either a first eccentric control cam or a second eccentric control cam, both of the first and second eccentric cams being rotatably coupled with an intermediate member supported by a support so as to vary an eccentricity of the intermediate member to a shaft axis of a driven shaft according to a rotation position of the first eccentric control cam, the first and second eccentric control cam, the intermediate member, the support, and the driven shaft constituting the cam shaft assembly. In an embodiment, a potentiometer is attached onto an end of a control rod integrally formed with the first eccentric control cam, the other end of the control rod being attached with a hydraulic actuator to rotate the control rod according to an engine driving condition.
Abstract:
A system for operating an internal combustion engine including an intake valve and an exhaust valve, the system including an exhaust valve gear for the exhaust valve which incorporates an exhaust variable valve timing mechanism. The system also includes an intake valve gear for the intake valve which incorporates an intake variable valve timing mechanism. A control unit operates responsive to a low-speed/low-load operating range of the engine and a low-speed/high-load operating range of the engine to condition the exhaust variable valve timing mechanism for providing advanced opening and closing timings of the exhaust valve to cause a reduced valve overlap between the intake and exhaust valves, and at the same time condition the intake variable valve timing mechanism for decreasing an opening duration of the intake valve to provide a retarded opening timing thereof after a top dead center and an advanced closing timing thereof. The control unit operates responsive to a low-speed/medium-load operating range of the engine to condition the exhaust variable valve timing mechanism for providing retarded opening and closing timings of the exhaust valve to cause an increased valve overlap between the intake and exhaust valves, and at the same time condition the intake variable valve timing mechanism for increasing the opening duration of the intake valve to provide an advanced opening timing thereof before the top dead center and a retarded closing timing thereof.
Abstract:
A drive mechanism includes an internal gear rotatably mounted on an eccentric, the eccentric being mounted on a drive shaft for rotation therewith, said internal gear having an arm with an elongate slot, a block being pivotally mounted on a pin slidably located in the slot, an external gear being rotatably mounted coaxially of the internal gear and in mesh therewith, the position of the pin being adjustable relative to the axis of the drive shaft.
Abstract:
An engine driven camshaft cam is driven in a manner to superimpose a variable oscillation on the cam as it is rotatably driven in order to vary the period during which an associated valve is opened, the drive including an engine driven gear or sprocket journalled in a block whose axis is displaceable transversely to the axis of the cam, a slider member secured for rotation with the gear and guided for linear radial movement relative to the gear or sprocket, and a rack on the slider member engaged by a pinion coupled to the cam for oscillating the cam relative to the camshaft upon sliding movement of the slider in response to eccentrically displacing the axis of the gear.
Abstract:
An object of the present invention is to obtain a controller device for a variable valve timing apparatus capable of controlling a phase to an arbitrary fixed valve timing from immediately before an internal combustion engine stops until after the internal combustion engine has stopped. The controller device for the variable valve timing apparatus according to the present invention performs, during engine stop processing of the internal combustion engine, normal control of changing the relative rotational phase of a camshaft to a most advanced position or a most retarded position when the rotational speed of a crankshaft is equal to or more than a first threshold, and low-speed control of fixing a current or a voltage supplied to the motor to be constant to maintain the relative rotational phase of the camshaft at the most advanced position or the most retarded position in a period from when the rotational speed of the crankshaft is lower than the first threshold until the rotational speed becomes zero.
Abstract:
A valve timing change device includes: a housing rotor (10); a vane rotor; a fastening bolt (40); and an advance angle oil passage communicating with an advance angle chamber and a delay angle oil passage communicating with a delay angle chamber, via oil passages which are open at intervals on an outer-circumferential surface of the fastening bolt. The vane rotor includes: a rotor body (20) formed of a material having a thermal expansion coefficient greater than that of the fastening bolt; and a rotor sleeve (30) that is formed of a material having a thermal expansion coefficient equal to that of the fastening bolt and is integrally incorporated such that the rotor sleeve does not contact a cam shaft and tightly contacts the outer circumferential surface (41a), in a region in which the advance angle oil passage (23a) and the delay angle oil passage (35) are blocked from each other.