Aisin Seiki Kabushiki Kaisha

Toyota Jidosha Kabushiki Kaisha

Junichi Kano

Kongoh Aoki

Koji Hotta

Atsushi Sato

Kongo Aoki

Yasushi Miura

Masahiro Mochizuki

Hiroyuki Nakadozono

A valve opening and closing timing control apparatus is disclosed, which includes an engine including a cam shaft and a crank shaft, a first sensor adapted for detecting rotary positions of the cam shaft, a second sensor adapted for detecting rotary positions of the crank shaft, a hydraulic pump driven by the crank shaft, a rotary phase varying means disposed on the cam shaft and adapted for varying rotary phases of the cam shaft, a hydraulic line connecting the hydraulic pump and the rotary phase varying means, a hydraulic control means disposed in the hydraulic line, an electronic control means adapted for controlling the hydraulic means and receiving output signals which are output by the first sensor and the second sensor at least, thereby operating the rotary phase varying means with the hydraulic control means under linear control. The electronic control means detects the rotary positions of the cam shaft and the crank shaft and operates the rotary phase varying means with the hydraulic control means under the linear control in order to establish an optimum valve opening and closing timing depending on engine conditions. Hence, the valve opening and closing timing control apparatus can establish the valve opening and closing timing at optimum and desired occasions, which distinguishes over the conventional digitized valve opening and closing timing.

Valve opening and closing timing control apparatus

A valve opening and closing timing control apparatus is disclosed, which includes an engine including a cam shaft and a crank shaft, a first sensor adapted for detecting rotary positions of the cam shaft, a second sensor adapted for detecting rotary positions of the crank shaft, a hydraulic pump driven by the crank shaft, a rotary phase varying means disposed on the cam shaft and adapted for varying rotary phases of the cam shaft, a hydraulic line connecting the hydraulic pump and the rotary phase varying means, an accumulator and a hydraulic control means, each disposed in the hydraulic line, an electronic control means adapted for controlling the hydraulic means and receiving output signals which are output by the first sensor and the second sensor at least, thereby operating the rotary phase varying means with the hydraulic control means under linear control. The valve opening and closing timing control apparatus can establish the valve opening and closing timing at optimum and desired occasions, which distinguishes over the conventional digitized valve opening and closing timing. Moreover, it is unnecessary to enlarge the hydraulic pump capacity because the accumulator supplies extra hydraulic pressures when the valve opening and closing timing should be varied considerably.

A valve opening and closing timing control apparatus is disclosed, which includes an engine including a cam shaft and a crank shaft, a first sensor adapted for detecting rotary positions of the cam shaft, a second sensor adapted for detecting rotary positions of the crank shaft, a first hydraulic pump and a second hydraulic pump driven by the crank shaft, a hydraulic pressure switching valve disposed between a discharge port of the first hydraulic pump and a discharge port of the second hydraulic pump and communicating therewith, a rotary phase varying device disposed on the cam shaft and adapted for varying rotary phases of the cam shaft, a hydraulic line connecting the hydraulic pump and the rotary phase varying device, a hydraulic control device disposed iin the hydraulic line, and an electronic control device adapted for controlling the hydraulic device and receiving output signals which are output by the first sensor and the second sensor at least, thereby operating the rotary phase varying device with the hydraulic control device under linear control. The valve opening and closing timing control apparatus can establish the valve opening and closing timing at optimum and desired occasions, which distinguishes over the conventional digitized valve opening and closing timing. Moreover, the engine driving losses can be suppressed because the hydraulic pressure switching valve bypasses the hydraulic pressures when the rotary phase varying device requires no hydraulic pressure.

A variable valve timing system comprises a first timing member driven by the engine, a second timing member rotatably fixed to the crankshaft, a helical device engaged between the first and second timing members and including a piston movable for adjusting an angular position between the first and second timing members, a hydraulic circuit device for selectively applying a hydraulic pressure to the piston for selectively moving the piston to adjust the angular position, a damper device on the first and second timing members for hydraulically damping rotational vibrations between the first timing member and the second timing member, and a notch formed at least on one of the first timing member and the second timing member in the damper device. Torque variations applied to the second timing member relative so the first timing member do not cause a change in the angular position.

Variable valve timing system in an engine having a rotating cam-shaft

A variable valve timing system includes a first timing member driven by the engine, a second timing member rotatably fixed to the crankshaft, a helical device engaged between the first and second timing members and including a piston movable for adjusting an angular position between the first and second timing members, a hydraulic circuit device for selectively applying a hydraulic pressure to the piston for selectively moving the piston to adjust the angular position, and a damper device on the first and second timing members for hydraulically damping rotational vibrations between the first timing member and the second timing member. The damper device includes the first timing member, a ring-member engaged with the second timing member and a viscous fluid between the first timing member and the ring-member.

A variable valve timing system in an engine having a rotating cam-shaft includes a timing pulley driven by the engine and a damper case rotatably fixed to the crank-shaft. A piston is movable in a space defined by the timing pulley and the damper case and has helical gears engaging helical gears of the timing pulley and damper case such that the angular position between the timing pulley and the damper case varies as the piston is moved. Movement of the piston is induced by hydraulic pressure in a pressure chamber selectively connected to hydraulic pressure by an electronically controlled solenoid valve. Engaging labyrinth grooves on the timing pulley and damper case damp rotational vibrations which would otherwise be induced by variations in the torque applied to the damper case, and so prevent undesirable movement of the piston.

Variable valve timing system having rotational vibration damping

A two-wheel and four-wheel drive transfer device includes a reciprocating fork shaft having a shift fork engagable with a sliding dog clutch so as to reciprocate the dog clutch and provide either two-wheel and four-wheel drive operating conditions. A motor is provided so as to rotate a worm gear assembly which is relatively rotatable with an output shaft supported in a casing. This worm gear is connected to and rotates a plate concurrently with rotation of the worm gear. A spring support plate is provided to be secured to the output shaft and two spiral springs, each spring being wound in a different direction and having a different rotating torque, are fixed to the output shaft and have ends brought into contact with the rotating plate and the spring support plate so that the rotating torque of the worm wheel is transmitted to the output shaft through the spiral springs depending on the direction of rotation of the worm gear.

Two and four-wheel drive transfer device

A two wheel drive/four wheel drive change over apparatus for four-wheel drive vehicles includes an actuator having a vacuum chamber. A tank storing an engine vacuum through a check valve is integrally formed in the vacuum chamber, whereby the engine vacuum stored in the tank can be used for operating the actuator.

Two wheel/four wheel drive change over apparatus for four-wheel drive

A rotary torque transmission apparatus for a 4-wheel drive vehicle in which a rotary torque of a worm wheel of 4-wheel drive vehicle provided with a reciprocably movable fork shaft, to which a shaft fork for moving a 2-4 wheel change over slider to and fro is fixed, is transmitted to an output shaft via a torsion spring, wherein the worm wheel driven by a motor is disposed on an output shaft supported by a casing so as to be rotatable relative to the output shaft; and a pair of rotary plates so arranged as to be rotatable together with the worm wheel is disposed inside the torsion spring arranged between a pair of fixed plates fixed to the output shaft in such a way that each end of the torsion spring is retained between one rotary plate and one fixed plate disposed on the opposing side to each other, respectively.

Growing community of inventors

Kariya, Japan

Junichi Kano