Abstract:
A device for varying valve timing in an internal combustion engine comprises an adjusting mechanism for varying an angle of rotation between a drive pinion (2) and a camshaft (end portion of the camshaft 1), said adjusting mechanism being configured as a wobble transmission. The drive pinion (2) comprises a first front-end gearing (9) and a disk (10) comprises a second front-end gearing (11), which first and second front-end gearings mesh partially with each other, and the number of teeth of said front-end gearings differ from each other by at least one tooth. To reduce the overall dimensions of the device and avoid gearing lash, it is proposed, on the one hand, to connect the disk (10) rotationally fast to the camshaft (1) and on the other hand, to configure the disk (10) in axial direction of the camshaft (1) as a flexible element that can be deformed in axial direction by an adjusting device (thrust plate 17).
Abstract:
A synchronous drive apparatus and method, wherein the apparatus comprises a plurality of rotors comprising at least a first and a second rotor. The first rotor has a plurality of teeth for engaging the engaging sections of an elongate drive structure, and the second rotor has a plurality of teeth for engaging the engaging section of the elongate drive structure. A rotary load assembly is coupled to the second rotor. The elongate drive structure engages about the first and second rotors. The first rotor is arranged to drive the elongate drive structure and the second rotor is arranged to be driven by the elongate drive structure. One of the rotors has a non-circular profile having at least two protruding portions alternating with receding portions. The rotary load assembly is such as to present a periodic fluctuating load torque when driven in rotation, in which the angular positions of the protruding and receding portions of the non-circular profile relative to the angular position of the second rotor, and the magnitude of the eccentricity of the non-circular profile, are such that the non-circular profile applies to the second rotor an opposing fluctuating corrective torque which reduces or substantially cancels the fluctuating load torque of the rotary load assembly.
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.