A valve opening and closing timing control device includes: a drive-side rotary body rotating synchronously with a crankshaft; a driven-side rotary body arranged coaxially with the drive-side rotary body and rotating integrally with a valve opening and closing camshaft; a fluid pressure chamber defined between the drive-side and driven-side rotary bodies; advance and retard chambers defined by partitioning the fluid pressure chamber; an intermediate lock mechanism selectively switches between a lock state and a lock release state; advance and retard flow paths allowing a flow of the working fluid to be supplied to and discharged from the advance and retard chambers; a control valve including a spool; and a phase control unit moving a position of the spool by controlling a power supply amount to the control valve to supply and discharge the working fluid to and from the advance and retard chambers to displace a relative rotation phase.

An electromagnetic switching valve includes: a sleeve, defining a port communicating with an oil passage; a spool, reciprocally movably disposed on an axis in the sleeve, opening and closing the port; an electromagnetic actuator, including a plunger disposed on the axis and a stator; a transmission member interposed between the plunger and the spool; and an energizing spring, energizing the spool toward the plunger. The transmission member includes a first abutting part of a convex shape tiltably abutting against a receiving recess of the plunger; a second abutting part of a concave shape abutting against a convex end of the spool; and an outer peripheral wall that, in a state of being deviated from the axis and inclined, regulates the inclination by contacting an inner peripheral surface of the sleeve or the stator.

A self-resetting single-valve hydraulic drive device and method based on primary and secondary pistons for a push rod engine is provided. A primary driving piston and a secondary driving piston are respectively provided on a rocker arm body and a valve bridge body. The secondary driving piston is connected to an exhaust valve. A driving oil passage connects the primary driving piston, the secondary driving piston and a drive control valve. When the drive control valve opens the driving oil passage, the primary driving piston and the secondary driving piston realize a hydraulic linkage. During a drive lift, the rocker arm body and the valve bridge body do not move, and the secondary driving piston opens the exhaust valve. In the beginning of a positive-power lift, a primary piston body oil passage and a secondary piston oil passage are closed, and the secondary driving piston is automatically reset.

A variable cam timing phaser has a rotor assembly with a central hub defining an axial bore and an interface groove with a first seal land, a second seal land and a single undercut area. A width of the first seal land is greater than a width of the second seal land. The single undercut area is in fluid communication with an axial undercut passage connected to a radial undercut passage within the rotor assembly. A clamping interface is between the camshaft and the rotor assembly, such that a seal is present between first seal land and the first end of the camshaft, and the second seal land and the first end of the camshaft. Fluid from a supply, flows into the passage of the camshaft to the single undercut area, through the axial undercut passage, the radial undercut passage to a passage within the rotor assembly.

A hydraulic fluid control valve (HFCV) configured to recirculate an exiting hydraulic fluid from a first hydraulic actuation chamber to a second hydraulic actuation chamber is provided. The HFCV includes a selectively movable spool having an outer annulus configured to receive and deliver the exiting hydraulic fluid to one or both of either a sump or one of the first or second hydraulic actuation chambers.

A hydraulically-actuated variable camshaft timing (VCT) system comprises a spool valve including a sleeve and a spool, having a plurality of radially-outwardly extending lands, received within the sleeve; a first fluid supply port in the sleeve configured to receive fluid from a fluid supply; a second fluid supply port in the sleeve configured to receive fluid from the fluid supply; an advancing port in the sleeve in fluid communication with an advancing chamber of a hydraulically-actuated camshaft phaser; a retarding port in the sleeve in fluid communication with a retarding chamber of the hydraulically-actuated camshaft phaser; and an exhaust port axially positioned in the sleeve in between the first fluid supply port and the second fluid supply port or in between the advancing port and the retarding port, wherein the exhaust port is configured to selectively receive fluid from either the advancing chamber or the retarding chamber depending on an axial position of the spool relative to the sleeve.

An actuator for a hydraulic valve for a cam phaser, the actuator comprising a magnetisable actuator housing that envelops a magnet coil; a pole group that is arranged in a housing receiver opening of the magnetisable actuator housing, wherein the pole group includes a pole core and a pole tube, wherein the pole core and the pole tube are connected by a connection bar and the pole core is connected with the connection bar by a pole core cone, or the pole tube is connected with the connection bar by a pole tube cone, wherein an armature is received axially movable in an inner space of the pole group.

Various embodiments of the teachings herein include a method for controlling a cam using an ECU (electronic control unit) comprising: learning a holding region in which linearity is not ensured by increasing or decreasing a PWM signal while the cam maintains a holding state; based on the results of the learning, generating a final PWM signal; and transmitting the final PWM signal to an oil control valve. The final PWM signal comprises a sum of a minimum PWM signal for the cam to leave the holding region and a control PWM signal for the cam to reach a desired position.

In a first state: a spool valve of a control valve is disposed such that a second spool oil passage is closer to a second side in a longitudinal direction than a first spool oil passage; and as the spool valve has traveled toward the second side against a biasing force of a biasing member, a first port communicates with a second port via the first spool oil passage, a first sleeve oil passage, and the second spool oil passage. In a second state: the spool valve is disposed such that the first spool oil passage is closer to the second side than the second spool oil passage; and as the spool valve has traveled toward a first side in the longitudinal direction, the first port communicates with the second port via the first spool oil passage, the first sleeve oil passage, and the second spool oil passage.

A control valve assembly of a variable cam timing phaser of a variable cam timing system, with the variable cam timing phaser including a housing and a rotor, and with the variable cam timing system including a camshaft, includes a valve housing extending along an axis. The valve housing includes a threaded portion adapted to engage the camshaft, and a body portion spaced axially from the threaded portion. The body portion defines a body interior. The control valve assembly also includes a piston disposed in the body interior and moveable along the axis between a first position and a second position. The control valve assembly further includes a cap removably coupled to the body portion of the valve housing. The cap includes a torque driving element configured to be received by a tool for transmitting torque from the tool for fixing the cap to the body portion.