Abstract: A system and method to control valve timing and valve lift of an engine is described. The valve timing can be adjusted to improve engine operation when a range of fuels are used. The method can improve engine performance and the energy utilization, at least under some conditions.

Abstract: A dynamic camshaft apparatus includes, according to one embodiment, a moveable camshaft connected to an engine. The moveable camshaft has a first position when the engine is started and at low RPMs. Further, the moveable camshaft is conformed to move to different positions as the RPMs change.

Abstract: The present invention relates to an adjustable camshaft in which an inside shaft and an outside shaft, each being fixedly connected to cams, are mounted so they are rotatable in relation to one another. To produce the relative movement, a hydraulic adjusting mechanism is provided on one of the ends thereof; in the adjusting mechanism, first and second rotatable adjusting elements are each fixedly connected to one of the two shafts opposite one another. Adjacent to the adjusting mechanism, the outside shaft is fixedly connected to a first bearing ring supporting at least the outside shaft in a stationary first abutment.

Abstract: The present invention relates to an adjustable camshaft (1) in which an inside shaft (4) is rotatably mounted with respect to an outside shaft (2). To create a relative rotational movement between the two shafts (2, 4), a hydraulic regulating device (3) is provided at one end of the camshaft (1) and a chain/belt wheel (7) that is connected to a drive, in particular to a crankshaft, via a chain or a belt is also provided. It is essential to the invention here that the chain/belt wheel (7) is designed so that it is rotatable in relation to the regulating device (3) for aligning the camshaft (1) with respect to the drive, and after successful alignment, it is connectable in a rotationally fixed manner to either the inside shaft (4) or to the outside shaft (2).

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: An actuator for a valve lift controller comprises a case forming a first and second spaces therein. The first space is supplied with lubricating fluid. The actuator further comprises a feed screw mechanism including a cylindrical spindle and a screw, and converts a rotational movement of the spindle to a linear movement of the screw. The spindle includes a first end portion open to the first space and a second end portion closed to the second space therein. The screw straddles borders between an interior of the spindle, the first space, and an external space. The actuator includes a motor unit which is located in the second space and rotates the spindle. The actuator further includes a sealing member sealing a gap between the case and the spindle to separate the first and second spaces.

Abstract: The invention relates to a method for controlling an actuator which can be displaced between two end positions, said actuator being impinged in one end position and being capable of displacement to the other end position by an electromagnetic part. The actuator is first supplied with an electromagnetic current using a pulse-duration modulation in a retaining mark space ratio. Once the application of current has ended, an oversaturation of the electromagnet is taken into consideration, either by influencing the application of current in the mark space ratio in an appropriate manner, or the oversaturation is completely prevented by a suitable configuration of the application of current.

Abstract: An actuator for a valve lift controller linearly driving a control shaft of a changing mechanism comprises a feed screw mechanism including a screwed shaft linearly moving along with the control shaft, and a rotation spindle rotating coaxially with the screwed shaft. The feed screw mechanism converts a rotational movement of the rotation spindle into a linear movement of the screwed shaft. Moreover, the actuator comprises a unit attached to the rotation spindle, an electric power distributor located at an opposite side of the screw mechanism relative to the changing mechanism, and an stopper member restricting a movement of the unit in the axial direction from an electric power distributor to the unit.

Abstract: A variable valve timing system in which the cam shaft is rotated with respect to the crankshaft position by moving a shaft disposed interior to the cam shaft longitudinally has been developed. The variable valve timing system provides for varying the timing of the opening and closing of an engine's poppet valves (relative to the crankshaft angular position) to enhance the engine's efficiency and output. The timing system can be used with both intake and exhaust valves in both diesel and gasoline engines. The timing system is inexpensive to produce, and performs reliably over a lengthy period of time.

Abstract: A cam 13 formed so that cam height and a cam operation angle continuously change, and constituted to be rotated integrally with a camshaft 11 and relatively movable in an axial direction thereof, a valve lifter 20 pressed by a cam surface of the cam 13 to advance and retreat a valve, and an accelerator shaft unit 40 for moving the cam 13 in the axial direction of the camshaft 11 are included. The accelerator shaft unit 40 includes an accelerator shaft 41 placed to be capable of reciprocating in the axial direction of the camshaft, and an accelerator fork 42 supported at the accelerator shaft 41 and engaging with the cam 13, and has an adjust mechanism 70 for finely adjusting a relative position in an axial direction of the accelerator fork 42 with respect to the accelerator shaft 41.

Abstract: The valve controller is driven by a motor. The valve controller has a control circuit and a driving circuit. The driving circuit drives a motor based on a control signal generated by the control circuit and a rotational position signal generated by a rotational position sensor. The driving circuit generates a rotation number signal representing an actual rotation number of the motor according to the rotational position signal, and transfers the rotation number signal to the control circuit.

Abstract: A three-dimensional cam of a three-dimensional map state, having uncountable cam profiles continuously ranged along a rotation axis direction, and a valve lifter following a cam surface of the three-dimensional cam are included, and a lift characteristic of a valve is continuously controlled by relative motions of the three-dimensional cam and the valve lifter. The three-dimensional cam has cam top portions formed to have a smoothly ranged edge line substantially along the rotation axis direction thereof, and a part of the edge line includes at least one valley portion to take on a row of peaks. The cam peak portion of the cam top portion which forms the valley portion of the edge line is moderately set to be deviated toward a delayed side with reference to the rotation direction of the cam from the other cam peak portions.

Abstract: A variable valve timing system for an internal combustion engine, comprising a drive shaft driven by the engine, a camshaft driven by the drive shaft, and a cam supported by the camshaft for bearing against a valve actuating member. The camshaft and the drive shaft have parallel, spaced apart fixed axes of rotation, and are interconnected by a drive link, one end of which is coupled to the drive shaft and the other end of which is coupled to the camshaft. Means are provided for varying the spacing between an end of the link and the axis of rotation of the shaft to which that end is coupled. The system eliminates the need to move the axis of the central drive shaft, or to move an intermediate member or the camshaft, and also eliminates the need to have a control shaft external to the drive shaft or camshaft. The invention also provides camshaft assemblies and linkages for connecting camshafts and drive shafts.

Abstract: A driving cam includes a circular surface portion at an outer cam surface thereof. When an engine is turned off, the circular surface portion is brought into contact with a roller. Thereby, even if a load is applied to the control axis member, no rotational force is circumferentially applied to the driving cam. As the result, even if a driving force is not applied from a motor to the driving cam, a rotational angle of the driving cam and an axial position of the control axis member are kept constant. Therefore, it is possible to keep the driving cam and the control axis member at a constant position without adding a complicated mechanism.

Abstract: An actuator is used for controlling an intake valve lift of an automotive engine. A control shaft is joined with a transmission device on its one end side, and is joined with a valve lift controller on the other end side. The control shaft is arranged perpendicularly to a spindle of a motor. Besides, the transmission device includes a drive cam internally. Thus, the actuator is reduced in size in a longitudinal direction of the control shaft regardless the length of the motor. When the motor rotates, the control shaft reciprocates in accordance with a cam profile of the drive cam. The intake valve lift can be precisely controlled by defining the cam profile, especially in a rotation range of the drive cam corresponding to the idling operation of the engine.

Abstract: Low load operating point for a controlled auto-ignition four-stroke internal combustion engine is reduced without compromising combustion stability through a valve control operative to establish sub-atmospheric pressure conditions within the combustion chamber into which fuel and exhaust gases are introduced.

Abstract: In an internal combustion engine provided with a variable valve mechanism that variably controls at least an operating characteristic (valve lift amount and the like) of an intake valve, a valve opening area AWm at a valve overlap time is calculated based on a valve lift amount (VCS-ANGL) and opening timing IVO of the intake valve, and a spit-back gas amount Wm at the valve overlap time is calculated based on the valve opening area AWm. On the other hand, a volume flow ratio (basic actual engine volume flow ratio) RQH0VEL1 in the intake valve, equivalent to an actual intake air amount of the engine, is calculated based on the valve lift amount and closing timing of the intake valve, and a basic residual gas amount Wcyl is calculated based on the basic actual engine volume flow ratio RQH0VEL1. Then, a resultant obtained by adding the spit-back gas amount Wm and the basic residual gas amount Wcyl, is set as a total residual gas amount of the engine.

Abstract: A region including an engaging hole is given surface treatment such as partial quench hardening by induction hardening for improving surface hardness of the region. The partial quench hardening by induction hardening provides the region with satisfactory mechanical strength or surface hardness enough for resisting deformation of the engaging hole and wear-out of an edge of opening of the engaging hole caused by putting in and out of the lock pin.

Abstract: An actuating device for hydraulically securing a camshaft of an engine of a motor vehicle in a start position has a solenoid valve controlling the flow of a pressure medium to a camshaft adjuster with a rotary slide valve that is fixedly connected to the camshaft and moves the camshaft into the required start position according to the pressure medium supplied to it by the solenoid valve.

Abstract: The invention relates to a device for converting a rotational displacement into a displacement back and forth. Said device comprises at least one control cam region, provided with a driven cam element, having an eccentric control surface, and a cam follower element that can be displaced or pivoted by the cam element. The cam element is rotatably mounted in a flexible encircling element which is displaceably connected to the cam follower element on a plane that is perpendicular to the rotational axis of the cam element. The encircling length of the flexible encircling element and the peripheral length of the control cam region are configured to correspond and can be modified.

Abstract: An adjustable valve control device for an internal combustion engine with a drive shaft, with a camshaft 1 rotated by the drive shaft, and with at least one valve actuated by the camshaft 1 with a specific timing. The valve control device modifies the rotary phase of the camshaft 1 relative to the drive shaft in order to modify the timing of at least one valve and comprises a first rotor 2 which rotates synchronously with the drive shaft, a second rotor 3 which rotates synchronously with the camshaft 1, and a lock bolt 14 for locking the first rotor 2 and the second rotor 3 relative to each other. Fluid is applied to the lock bolt 14 by way of a separate line 15 to lock the rotors and is removed to unlock the rotors.

Abstract: A valve drive system capable of reducing the friction resistance of rocker arms and facilitating replacement work of tappet-clearance adjusting shims. The valve drive system can comprise a rocker arm that is slidable between a first position at which the pushing portion engages the shim and a second position at which the pushing portion is disengaged from the shim, and held in the first position through a spring.

Abstract: A VCT phaser for an internal combustion engine with at least one camshaft comprising a housing, a rotor, a spool valve and a ring-shaped reservoir. The housing having at least one chamber and the rotor having at least one vane dividing the chambers into advance and retard. The spool valve is comprised of a spool mounted within a bore of the rotor. The reservoir is defined within the bore by an oil dam and at least one of the spool lands. The spool has a first position in which a chamber is coupled to the supply and the other chamber is exhausting fluid and a second position in which a chamber is coupled to the supply and the other chamber is coupled to the reservoir. When a torque reversal occurs, hydraulic fluid pooled in the reservoir is drawn into the other chamber when the spool is in the second position.

Abstract: A camshaft adjusting device for internal combustion engines of motor vehicles has an intake camshaft adjuster and an exhaust camshaft adjuster driven by an endless drive connected to the crankshaft. The intake and exhaust camshaft adjusters are connected by a gear transmission to one another. The intake and exhaust camshaft adjusters each have a gear forming a part of the gear transmission. The intake and exhaust camshaft adjusters are directly drivingly connected by the gears or a common gear wheel fixedly connected to an intermediate shaft is positioned between the gears.

Abstract: A variable valve timing control device includes a rotation member for opening or closing a valve, a rotation transmission member engaged with the rotation member to be relatively rotatable, a vane provided on either one of the rotation member or the rotation transmission member, a hydraulic chamber formed between the rotation member and the rotation transmission member and including an advance angle chamber and a retarded angle chamber, the advance angle chamber and the retarded angle chamber being formed by dividing the hydraulic chamber by the vane, a first hydraulic passage for supplying and discharging a fluid to the advance angle chamber, and a second hydraulic passage for supplying and discharging the fluid to the retarded angle chamber. The vane includes a surface hardness determined to be higher than a surface hardness of a sliding surface of the rotation member or the rotation transmission member for sliding the vane.

Abstract: A lead frame disposed within the confines of an engine cover, having an insulating portion and an electrically conducting portion. The conducting portion has at least one electrically conducting interconnect. Both the insulating portion and the electrically conducting portion form an integral piece for retaining and accurately positioning devices within an internal combustion engine. The lead frame includes a plurality of retaining elements for retaining or positioning of at least some of the devices; and an electrical connector member extending outside the confines of the internal combustion engine, the electrical connector member having a plurality of electrically conducting terminals in electrical communication with at least some of the devices within the internal combustion engine by means of the at least one electrically conducting interconnect, whereby at least some of the devices are retained and accurately positioned within the internal combustion engine.

Abstract: A shim attaching and detaching surface has a sectional portion with a smaller diameter than a base circle of a cam surface in a state in which the shim attaching and detaching surface of a cam is located on a tappet roller, and therefore the tappet roller and an arm member can be moved upward. Since an inner side of a top surface of a tappet guide is inclined, if the arm member is tilted along this inclination, one end of the arm member can be raised, and a clearance is formed in a space from a tappet shim. Accordingly, by inserting a slim plate-shaped or rod-shaped jig 128 from the clearance, the tappet shim 37EX can be attached and detached.

Abstract: A device for hydraulically adjusting the rotation angle of a camshaft with respect to a crankshaft of an internal combustion engine: A drive unit connected to a crankshaft and an output unit connected to a camshaft, having radially extending, axially facing sides secured by the pre-stressing force of a central securing bolt. The drive unit is rotably mounted to the output unit and they are so connected that at least two hydraulic pressure chambers transmit relative rotation forces. An annular disk with coating on opposite sides increases the frictional force between the end face of the output unit which faces the camshaft and the end of the camshaft and enables reduction of the pre-stressing force on the bolt. The character of visually detectable elements on the disk enable detection of the presence or absence of the disk.

Abstract: An improved cam and follower arrangement suitable for actuating, for example, poppet valves of an internal combustion engine and method and apparatus for forming the cam surface. This permits the use of skewed valve axes without using multiple rocker arms for each valve. The shapes are chosen and formed to provide better contact area and permits the cams to be ground with conventional grinding methods and for multi-cylinder engines.

Abstract: To operate a steplessly adjustable camshaft control device, particularly reliably and safely, an adaptation of the camshaft and the crankshaft is performed so that a phase angle (actual value) of the camshaft to the crankshaft is determined, the phase angle is monitored while operating the internal combustion engine and the camshaft control device is controlled as a function of a variable setpoint value so that the phase angle is equivalent to the setpoint value.

Abstract: A variable timing duration camshaft has an outer shaft (1) and coaxial inner shaft (2) adapted so that the shafts (1, 2) are relatively slidable but not rotatable about each other. The outer shaft (1) has valve control lobes located on its outer surface and a valve control lobe modifying segments (4) is located on the inner shaft (2) and is slidingly fitted into a mating slot (5) in the outer shaft and in the valve control lobe whereby longitudinal axial movement of the inner shaft (2) relative to the outershaft by a control means (13, 14) causes the modifying segment (4) to move longitudinally and circumferentially relative to the valve control lobes thereby varying the duration.

Abstract: An engine unit includes a valve driving mechanism in which a cam having its cam profile axially varying continuously is slid along the axis of the cam shaft to control continuously a lift characteristic of an intake valve to be steplessly variable. In the control device of the engine, when the engine is, determined to be in a idling state by an idling-state determining unit, a target cam position is obtained according to a target valve lift amount calculated based on the cooling water temperature by a target cam position calculated unit, and the target cam position is corrected according to atmospheric pressure, an engine oil temperature, an ATF temperature, and an intake temperature, so that an engine rotation will be stabilized in the idling state.

Abstract: The invention concerns a control device for adjusting the relative angular position of a driven shaft, particularly a camshaft of an internal combustion engine, said device comprising a drive pinion that is rotatably connected to the shaft, an adjusting element (1) for the angular adjustment of the drive pinion relative to the shaft, two chambers (2, 3) that are alternately supplied with hydraulic fluid and a control valve (6) for actuating the adjusting element (1), said control valve being connected to the chambers (2, 3) of the adjusting element (1) through pressure medium channels (4, 5). The control valve (6) comprises a valve body (7) that has two working connections A and B for the pressure medium channels (4, 5), a delivery connection P for the supply of hydraulic fluid and a discharge connection T for the discharge of hydraulic fluid, and the control valve (6) further comprises a sliding valve control piston (8) for setting different hydraulic resistances W between the individual connections.

Abstract: The current invention provides an inexpensive variable valve mechanism that includes a first intervening member which rotates a small angle rotation about an axis of a support shaft by being pressed by a rotating cam and a second intervening member which lifts a valve by making a small angle rotation about an axis of the support shaft together with the first intervening member thus pressing a cam corresponding part of a rocker arm.

Abstract: A method of variably actuating a valve of an engine includes selecting one of three valve lift profiles dependent at least in part upon engine operating conditions and parameters. The selected valve lift profile is phased relative to the angular position of the engine crankshaft dependent at least in part upon engine operating conditions and parameters. The valve is actuated according to the selected and phased valve lift profile.

Abstract: An intake quantity control apparatus for an internal combustion engine which controls a valve opening characteristic and intake pressure to control the intake quantity more suitably is provided.

Abstract: A control apparatus is provided for a valve actuating system which is operable to lift an intake valve or an exhaust valve of an internal combustion engine and includes a lift characteristic changing mechanism for changing a lift characteristic of the intake valve or the exhaust valve. The control apparatus calculates a target operation value of the lift characteristic changing mechanism, and calculates a realizable range of the operation value which can be realized by the lift characteristic changing mechanism, based on a controlled variable that can be given to the lift characteristic changing mechanism and at least one parameter related to an environment surrounding the lift characteristic changing mechanism. If the target operation value is not within the realizable range of the operation value, the control apparatus calculates a new target operation value to be within the realizable range.

Abstract: A variable valve timing apparatus rotatably receives a rotor in a housing. The rotor can rotate within a predetermined angular range. In some cases, the rotor is locked by a lock pin at an intermediate position within the angular range. In this manner, it is possible to realize a suitable valve timing even when an engine is restarted after it is stopped. In some case, the rotor is prevented from moving to the largest delay angle position by a restricting pin. In this manner, it is possible to prevent the rotor from reaching the largest delay angle position before the engine is stopped. On the other hand, while the engine is operated, it is possible to rotate the rotor to the largest delay angle position and to realize a valve timing responsive to the state of operation.

Abstract: A phaser for maintaining an angular relationship between a crank shaft and a cam shaft or among more than one cam shafts is provided. The phaser includes a rotor having a plurality of vanes integral to the rotor and protruding from the rotor body. The plurality of vanes is disposed to oscillate within their respective chambers formed by the rotor and a housing, thereby maintaining the angular relationship. The phaser also includes a shoulder integral to the rotor and interposed between one of the pluralities of vanes and the rotor body, thereby ensuring that the rotor face is always covering a locking pin hole regardless of vane position. The phaser further includes an inlet check valve located within the phaser structure or in very close proximity to the phaser, thereby reducing control fluid leakage.

Abstract: A valve timing control device for an internal combustion engine, in which upon cold start, combustion gas containing quench hydrocarbons and wet fuel is confined in a combustion chamber by advancing an exhaust valve close timing. This combustion gas is richer in hydrocarbons and wet fuel than is the gas produced after the engine has been warmed up. When the pressure in an intake line becomes lower than 600 mmHg, the exhaust valve close timing is retarded so as to recirculate post-combustion gas back to the combustion chamber. Then the unburned hydrocarbons in the post-combustion gas are involved in combustion again and their emission is reduced. Such gas recirculation and confinement to the combustion chamber are switched in accordance with a target valve underlap corresponding to the intake line pressure in the internal combustion engine.

Abstract: A valve control mechanism for an internal combustion engine includes a camshaft carrying cams which cooperate with and thereby actuate valves which control the induction of fluids into, and the exhaustion of fluids from, a combustion cylinder during the operating cycle of an engine. The camshaft is axially movable within a predetermined range of movement. At least one of the cams has a profile which, when viewed in a plane perpendicular to the axis of the camshaft, varies as a function of the position along the camshaft axis and is such that, when the camshaft is moved axially to one extreme of its permitted movement, interaction between the cam and the valve with which it is associated generates no valve movement when the cam is rotated.

Abstract: An output from each of output rods is converted into an assisting force via a corresponding one of rollers, while an outer peripheral surface of each of the rollers moving together with a control shaft serves as a conversion plane. This output is applied to the control shaft. Hence, as the control shaft is moved in such a direction as to increase valve lift amounts of intake valves, the assisting force can be correspondingly increased. Thus, a suitable assisting force that can act against a thrust force can be applied to the control shaft. As a result, there is no apprehension that a minimum hydraulic fluid pressure will not be ensured on the side of a larger valve lift amount or that responding properties in movements of the control shaft will deteriorate.

Abstract: A system and method for controlling air charge motion in the cylinder of a direct injection spark ignition engine during transitions between different combustion modes is provided. The system includes a cam profile switching device that controls the position of an intake valve for the cylinder. The system further includes an electronic control unit configured to control the cam profile switching device to position the intake valve in a first position in advance of the transition and to move the intake valve to a second position when a predetermined condition for transitioning between the two combustion modes is met.

Abstract: An oil pressure control apparatus which includes a source of hydraulic pressure introducing the hydraulic pressure to a hydraulic actuator which is actuated by hydraulic pressure, a fluid passage which is connected between the source of hydraulic pressure and the hydraulic actuator for introducing and discharging hydraulic pressure from the source of hydraulic pressure to the actuator, a control valve which is disposed in the fluid passages for controlling the hydraulic pressure and a filter is disposed in a position that is between the actuator and the control valve. Thereby, the control valve is capable to be operated smoothly.

Abstract: A variable timing duration camshaft has an outer shaft (1) and coaxial inner shaft (2) adapted so that the shafts (1, 2) are relatively slidable but not rotatable about each other. The outer shaft (1) has valve control lobes located on its outer surface and a valve control lobe modifying segments (4) is located on the inner shaft (2) and is slidingly fitted into a mating slot (5) in the outer shaft and in the valve control lobe whereby longitudinal axial movement of the inner shaft (2) relative to the outershaft by a control means (13, 14) causes the modifying segment (4) to move longitudinally and circumferentially relative to the valve control lobes thereby varying the duration.

Abstract: A fuel pump for an internal combustion engine that transmits fuel with pressure by a lifting movement of a plunger that is caused to lift by a movement of a cam includes a lift amount changing mechanism. The lift amount changing mechanism includes a cam in which a height of a projection is varied along an axial direction of the camshaft, and a cam moving actuator that moves the cam along the axial direction of the camshaft. The lift amount of the plunger is changed by moving the cam along the axial direction of the camshaft. An amount of discharged fuel is controlled by changing the amount of discharged fuel per stroke of the plunger and is not determined only based upon the rotation speed of the engine. Therefore, the amount of discharged fuel can be increased with the engine rotated at a low speed, for example when the engine is being initially started, to improve a starting performance.

Abstract: A device for controlling an internal combustion engine, comprising a variable valve mechanism for varying opening areas (valve lift) or the working angles (valve-opening periods) of at least either the intake valves or the exhaust valves, wherein a pressure in the cylinder is calculated based on the opening area or the working angle of at least either the intake valve or the exhaust valve varied by the variable valve mechanism, and the internal combustion engine is controlled based on the pressure in the cylinder. Upon calculating the pressure in the cylinder based on the opening areas or the working angles of the intake and exhaust valves, it is possible to more suitably control the internal combustion engine based not only upon the peak combustion pressure in the cylinder like when a combustion pressure sensor is used but also upon a pressure in the cylinder at a moment other than the peak combustion pressure.

Abstract: In a camshaft adjustment device for an internal combustion engine, with at least one sensor unit and one actuator unit, at least two functional units are supported on a common carrier unit and combined into a module for mounting on the internal combustion engine.

Abstract: An arrangement is provided for relative angle-of-rotation adjustment of a camshaft of an internal-combustion engine with respect to a driving wheel. An interior part, non-rotatably connected with the camshaft, has at least approximately radially extending webs or vanes. A driven cell wheel has several cells distributed along the circumference and bounded by webs. The camshaft is rotatable by way of the webs or vanes between two end positions relative to the cell wheel, and the interior part is laterally bounded by two cover elements connected with the cell wheel. Recesses forming chambers are provided to reduce friction between the webs or vanes of the interior part and the cover elements in the side walls of the vanes directed to the cover elements. During operation of the internal-combustion engine, the recesses are at least partially acted upon by hydraulic oil.

Abstract: A process and a device for controlling selective cylinder filling in combustion engines with a variable valve drive, where the valve stroke and/or the valve opening and closing times of the cylinder intake valves are controllable. In order to ensure satisfactory idling quality also in direct fuel-injection engines in spite of the occurring production tolerances, at least one input magnitude is determined on whose basis conclusions can be drawn as to the filling level or filling level differences of each cylinder. From this input magnitude, a control signal for the variable valve operation is determined such that differing filling levels of the cylinder can be balanced out by adjusting the valve drive.