Abstract: Hydraulic valve actuation systems and methods to provide variable lift for one or more engine air valves by way of a variable position hard stop. Various embodiments are disclosed, including embodiments controlling lift by providing a choice of two different fixed stops, three different fixed stops, stops continuously variable throughout a range of lifts, and a fixed stop and stops continuously variable throughout a range of lifts. The valves controlled by a variable position hard stop may be a single engine intake or exhaust valve, or multiple valves of any number, and of either intake or exhaust valves or both, or of one intake or one exhaust valve for one or more cylinders in engines having more than one intake or exhaust valve per cylinder. Dashpot deceleration of engine valve velocity on opening to the hard stop and on engine valve closure is disclosed, as are other aspects and embodiments of the invention.

Abstract: A variable valve drive for changing control timing of cam-actuated gas-exchange valves of an internal combustion engine is provided, with a tappet (6a, 6b, 6c), which, with convex cam engaging contour (5), engages a cam (4a, 4b, 4c) of a camshaft (3a, 3b, 3c) and which is guided so that it can move in the longitudinal direction in a rotatable tappet guide (7a, 7b, 7c), whose rotational angle (9) is adjustable for changing the control timing. In this way, the tappet guide (7a, 7b, 7c) can rotate about a rotational axis (8) parallel to a longitudinal axis (2) of the camshaft (3a, 3b, 3c).

Abstract: A variable valve operating mechanism of a four-stroke internal combustion engine includes a slide pin energized by a pin spring in a direction while oil pressure acting on the slide pin in the opposite direction through oil pressure supply passages. The slide pin moves by controlling the oil pressure causing a stem contact surface and a stem through hole to selectively face a valve stem. The mechanism also includes an oil discharge passage including a discharge port which is opened to allow oil acting the slide pin to be discharged when the valve lifter is pressed by a valve operating cam to move for opening the valve. The mechanism is capable of quickly moving the slide pin upon the release of oil pressure when the valve comes into a quiescent state. Therefore, the response of transitioning the variable valve from an operating state to the quiescent state is improved.

Abstract: There is provided a cam follower in which a surface roughness of an outer surface of a roller of a cam follower which is in rolling contact with a cam of an engine is obtained individually in an axial direction and a circumferential direction, a skewness Rsk of a profile is formed to be negative, a core roughness depth Rk is made to be 0.3 or less, a reduced valley depth Rvk is made to be 0.3 or less, and a ratio Rk/Rt of the Rk to a maximum height Rt of the profile is made to be 0.19 or more.

Abstract: A variable valve gear for internal combustion engines, having at least one camshaft and pivot lever disposed in the cylinder head, which lever contacts a valve that closes by means of spring force. An intermediate element of a transfer element is mounted in a supporting and displaceable manner, twice on the supporting body and on the pivot lever. The intermediate element engages a supporting surface disposed on the supporting body, first by way of a supporting cam segment disposed on the intermediate element, and second with the controlling cam segment of the supporting body, and third with the pivot lever, by way of an outer contour surface disposed on the intermediate element. The intermediate element indirectly contacts the cam of the camshaft, by way of a roller disposed on an oscillating crank, which is connected with the intermediate element in articulated manner.

Abstract: First and second connecting portions 61a and 62a are arranged in parallel and relatively turnably connected to a rocker arm 36 and a movable support portion 62b of a second link arm 62 is placed nearer to an engine valve 19 than a fixed support portion 61b of a first link arm 61. This makes it possible to decrease the size of a valve operating system and ensure the follow-up ability of the opening/closing operation as well as to vary a lift amount of the engine valve continuously while maintaining the reliability and durability of drive means.

Abstract: A current value of an intake valve phase calculated based on a sensor output is smoothed along the direction of time axis in accordance with a smoothing factor, whereby a phase detection value is detected. At the time of reference position learning, the smoothing factor is set to a value larger than at the time of normal control, so that the degree of smoothing in the smoothing process of phase detection value becomes smaller. Therefore, it is possible to detect more quickly that the intake valve timing has reached the reference timing at the time of reference position learning based on the phase detection value, than when a common smoothing factor is set both for the normal control and for the reference position learning.

Abstract: A valve actuator for operating a gas exchange valve of an internal combustion engine has a sleeve-shaped positioning piston which is connected to a valve stem, has at least two shell-shaped wedge pieces enclosing a stem end of the valve stem, whose radially outer peripheral surfaces have a conical segment which tapers off with increasing distance from the gas exchange valve and which is at least partially surrounded by a conical clamping sleeve having a mating conical inner surface and is connected to the positioning piston. The wedge pieces are axially form-fittingly and rotatably connected to a threaded bolt. A threaded segment is provided on the threaded bolt via which the wedge pieces and the conical clamping sleeve are axially attachable to one another.

Abstract: A hydraulic valve driving device includes a valve actuator operable to drive an engine valve, a hydraulic pump that generates the oil pressure for the valve actuator, a hydraulic pump driving motor that drives the hydraulic pump, and a starter motor. At the time of engine starting, after the hydraulic pump is driven by the hydraulic pump driving motor while the crank is stopped in the first engine-starting mode, and then the crank and the hydraulic pump are driven by the starter motor in the second engine-starting mode.

Abstract: A method of controlling a valve of a cam phaser of an internal combustion engine includes determining a delta duty cycle from a position error and a rate of change of error (error dot). A fuzzy gain value is calculated from the delta duty cycle and a correction term. A duty cycle is calculated from an integral gain value and the fuzzy gain value. The duty cycle is then used to control the valve of the cam phaser.

Abstract: In a guide gib for the valve operating mechanism of an internal combustion engine, having holding spaces (12, 13), which are arranged in the gib (8) at intervals one behind the other, for valve tappets, wherein to prevent a valve tappet from rotating about its central longitudinal axis in each case, flattened portions (14, 15) are formed within the associated holding space (12, 13) of the guide gib (8), it being possible for flattened portions of the valve tappet to bear against said flattened portions (14, 15), according to the invention, the guide gib (8) is formed by a plastic support (9) and a plurality of inlay parts (10, 11) which are provided with the holding spaces (12, 13), each of said inlay parts (10, 11) being made of a higher-strength material than the material of the plastic support (9) and being inserted into the plastic support (9).

Abstract: A rocker arm cover comprises a shell having an upper portion and a lower portion formed by inner and outer side walls and end walls contiguous therewith. A dividing wall is joined to the side walls and end walls to define an upper cavity in the upper portion of the rocker arm cover and to define a lower cavity in the lower part of the rocker arm cover. A lid is fitted to the upper portion of the rocker arm cover to provide an enclosed cavity for housing the plurality of ignition coils.

Abstract: A valve timing system for an internal combustion engine includes a phase alteration mechanism interposed between a driving rotator and a driven rotator and having a direction turning point at which the phase alteration direction is reversed when a movable portion of the mechanism travels from a beginning to a termination, and an operation control device for displacing the movable portion when undergoing an energization control, the movable portion being displaced toward the beginning when the energization control fails to be carried out. The rotation phase is set at a middle position between a maximum retard position and a maximum advance position when the movable portion is located at the beginning.

Abstract: An abnormality diagnosis system 100 includes a VVT controller 110, an adjustable valve mechanism 120, a cam angle sensor 130, a model computation module 140, an abnormality detection module 150, and an alarm lamp 160. The adjusable valve mechanism 120 advances or delays a phase angle of an intake cam shaft relative to a crankshaft, thereby varying an open-close timing of a valve. The model computation module 140 computes a physical behavior of the adjustable valve mechanism 120 according to a physical model, in response to a control signal input from the VVT controller 110. The abnormality detection module 150 determines whether the adjustable valve mechanism 120 is abnormal or normal, based on a difference between a theoretical value of phase angle calculated according to the physical model and an observed value of phase angle measured with the cam angle sensor 130. The arrangement of the invention ensures highly accurate abnormality diagnosis of the adjustable valve mechanism 120.

Abstract: A valve timing controller includes a housing which is biasedly assembled in such a manner that the housing is previously moved in a direction where a rotor knocks the housing. A camshaft rotatably extends through a through-hole provided in a sprocket and is engaged with a camshaft-inserting hole provided in the rotor. An inner diameter of the camshaft-inserting hole is lager than an inner diameter of the through-hole provided in the sprocket in order to prevent the camshaft-inserting hole from overlapping the through-hole.

Abstract: Camshaft adjusters according to the swivel motor principle may be provided with a bar which arrests the rotor in a position relative to the stator. A bar according to the invention is provided with two portions, between which a change of power transmission takes place during the arresting process.

Abstract: A valve timing correction control apparatus for an internal combustion engine is provided. The engine includes a plurality of banks and variable valve operating mechanisms disposed at the respective banks for variably controlling valve timings of intake valves separately at the respective banks. The valve timing correction control apparatus comprises air/fuel ratio sensors provided to exhaust systems of the respective banks, and a control unit that corrects the valve timings of the intake valves at the respective banks in accordance with deviations of air/fuel ratios detected by the respective air/fuel ratio sensors. A valve timing correction control method is also provided.

Abstract: A driving-side rotatable body includes a driving-side inner gear, which has an axial extent that does not overlap with an axial extent of a driven-side inner gear of a driven-side rotatable body. A driven-side outer gear and a driving-side outer gear of a planet gear are meshed with and are driven together with the driven-side inner gear and the driving-side inner gear, so that the planet gear changes a relative rotational phase between the driven-side rotatable body and the driving-side rotatable body. An addendum circle of the driving-side inner gear has a diameter, which is larger than that of a dedendum circle of the driven-side inner gear.

Abstract: A gas exchange valve of an internal combustion engine, has valve lifting movements with valve displacement curves and a control unit. To this end, a control unit is provided for operation of at least one valve, in particular a gas exchange valve of an internal combustion engine, in which the valvelifting movement of the at least one valve (6) is generated by superimposing two synchronously rotating cam profiles acting mechanically on a lift operating element (4). The two cam profiles (1, 2) have specially shaped areas by means of which, when superimposed to form one of the two cam profiles (1, 2), at least one additional valve displacement (ZV) can be generated on the whole in addition to a main valve displacement movement (HV) over a full revolution of each of these cam profiles (1, 2).

Abstract: A system for controlling electromechanical of an internal combustion has a valve-closing electromagnet for attracting the armature coupled to the valve to close the valve, a valve-opening electromagnet for attracting the armature to open the valve, a valve-opening spring for biasing the valve open, and a valve-closing spring for biasing the valve closed. The method includes de-energizing the valve-closing electromagnet for a predetermined time, enabling the valve to oscillate by the valve springs, and then energizing the valve-closing electromagnet to close the valve. Consequently, only the valve-closing electromagnet is energized to open and close the valve. The valve biasing springs force the valve to a location at which the valve-closing electromagnet can close the valve. This provides an electrical energy over prior methods in which both the valve-opening and valve-closing electromagnets are energized to actuate the valve.