A valvetrain for an internal combustion engine has a camshaft that can be rotated in a direction of rotation around an axis of rotation, at least two cam pieces arranged on the camshaft which each have at least two cams for actuating a respective gas exchange valve and which are rotationally fixedly connected to the camshaft, and an actuator via which the cam pieces can be shifted in the axial direction of the camshaft. A first of the cam pieces has a first rib protruding outwardly from a first base body of the first cam piece in the radial direction of the camshaft and the second cam piece has a second rib protruding outwardly from a second base body of the second cam piece in the radial direction of the camshaft.

A driven rotational body rotates relative to a driving rotational body to change a rotational phase therebetween and brings its driven-side stopper wall into contact with a driving-side stopper wall of the driving rotational body in the relative rotational direction. The planetary gear performs a planetary motion while being meshed with the driving rotational body and the driven rotational body to change the rotational phase. The driving rotational body includes a gear member, a cover member, and a fastening member. The gear member has the driving-side stopper wall and is meshed with the planetary gear. The cover member covers an accommodation space, in which the driven rotational body and the planetary gear are accommodated, together with the gear member. The fastening member axially fastens the gear member with the cover member.

A camshaft phaser arrangement configured for a concentric camshaft assembly having inner and outer camshafts is provided. The camshaft phaser arrangement includes a first camshaft phaser that is configured to be non-rotatably connected to both the inner and outer camshafts, and a second camshaft phaser that is configured to be non-rotatably connected to one of the inner or outer camshafts.

A method according to the invention for controlling an internal combustion engine having a camshaft whose phase with respect to a crankshaft can be adjusted by means of an electric adjustment device, and a control device comprises the steps S1 to S3, wherein in step S1 a stop request is output from the control device to the electric adjustment device. Subsequently, in step S2 a manipulated variable in the form of a pulse duty factor is output from the electric adjustment device, wherein the pulse duty factor counteracts a camshaft torque. In step S3, the direction of rotation of the camshaft is monitored, wherein in step S4, when a reversal of the direction of rotation of the camshaft is detected, an intensity level of this reversal of the direction of rotation is calculated by determining a rotational speed gradient. Furthermore, in a step S5 the pulse duty factor is corrected as a function of the rotational speed gradient in such a way that the influence of the reversal of the direction of rotation on the position of the camshaft is compensated.

A cam phaser is described for selectively engaging in a torque transmitting mode or an angle control mode. In the torque transmitting mode mode, torque from a camshaft is transmitted to an e-motor, which functions as a generator and provides electrical energy.

A phase adjustment mechanism for setting a relative rotational phase of a driven-side rotational body to a drive-side rotational body of a valve opening-closing timing control device includes a output gear around a rotational axis, an input gear being rotated around an eccentric axis, and an eccentric member. The eccentric member includes an outer peripheral surface with a first arc portion, a second arc portion, a plate spring fitted between the first arc portion and the second arc portion, and a spaced portion. Each of the first arc portion and the second arc portion is disposed from a position less than 90 degrees to a position more than 90 degrees as a central angle with respect to the eccentric axis from a biasing direction of the plate spring in the peripheral direction.

Travel of a brushless rotary actuator is limited by two stops, including a wound stator and a magnetic cylindrical rotor rigidly attached to a shaft having a first end rigidly attached to a control member. A second end of the shaft is rigidly attached to a travel limiting part acting as stops, and the travel limiting part has bending, resilient beam shapes. The actuator is electrically controlled in an open-loop. A control system controls a lift value of valves of an internal combustion engine by a lever driven by such an actuator.

A high efficiency uniflow steam engine having automatic poppet valves yieldably based by fluid such as steam held under pressure within a cavity in the engine and a cutoff control for closing a steam inlet valve at any time selected stops the flow of steam into the cylinder. Proximate the end of the exhaust stroke, around 0.12 inch before TDC the cylinder is sealed to thereby compress residual steam as the piston clearance approaches zero; typically, 0.020 inch which raises cylinder pressure enough to open an inlet valve without making physical contact to push the inlet valve open with the piston thereby eliminating a tappet type of noise, shock and wear.

An electric motor for an electric camshaft phaser, including: a housing; a nut fixed with respect to the housing and including a first plurality of threads; a drive shaft including a second plurality of threads, a portion of which is meshed with the first plurality of threads, and including a first segment; a rotor rotationally fixed to the drive shaft, and radially surrounding the drive shaft; a stator radially surrounding the rotor, and arranged to be energized to rotate the rotor and the drive shaft; and a first blocking element. The drive shaft is rotatable with respect to the nut, and the first segment is arranged to connect to the electric camshaft phaser to rotate an output gear of the electric camshaft phaser. A rotation of the drive shaft, in a first circumferential direction, is blocked by a contact of the first blocking element with the nut.

The present invention has: a crank angle sensor 4 that outputs a crank angle signal in response to rotation of a crankshaft 2, the crank angle signal being preset to indicate reference positions; a cam sensor 5 that outputs cam signal pulses in response to rotation of an intake camshaft 3 for opening and closing an engine valve; an electric motor 6 that relatively rotates intake camshaft 3 with respect to crankshaft 2, so that electric motor 6 can change a rotational phase angle of intake camshaft 3 with respect to crankshaft 2; and an electronic control unit 7 that computes an actual rotational phase angle of intake camshaft 3 based on a first cam signal pulse detected after start of cranking and a first reference position of the crank signal detected thereafter, to calculate an absolute position of a variable valve timing mechanism 14.