Toyota Jidosha Kabushiki Kaisha

Denso Corporation

Mitsubishi Jidosha Kogyo Kabushiki Kaisha

Nippon Soken, Inc.

Yu Yokoyama

Toshiyuki Yano

Yuta Nishimura

Atsuhisa Tamano

Toru Sakuma

Haruhito Fujimura

Soichiro Suga

Shinichi Murata

Shuhei Oe

Katsuhiko Miyamoto

Toshiki Fujiyoshi

Yoshiki Endo

Takeshi Hasegawa

Hideki Miyamoto

Keisuke Hotta

Yoshiyuki Hoshiba

Shota Toda

Kiyotaka Hosono

Tomoharu Sakai

Takafumi Shigemori

Toshiaki Umemura

For example, two intake valves for each cylinder each are driven by a selected one of cams via a corresponding rocker arm. Each rocker arm includes a support portion and a pressing portion (distal end portion). The support portion is rockably supported by a cylinder head. The pressing portion is configured to press a stem of the corresponding intake valve. The support portion of one of the rocker arms deviates to one side in an axis X direction (cam axial direction) with respect to the distal end portion. The support portion of the other one of the rocker arms deviates to the other side in the axis X direction with respect to the distal end portion.

Variable valve mechanism for engine

A variable valve mechanism includes a camshaft and a cam unit. Internal spline teeth provided at an inner periphery of a sleeve of the cam unit are in mesh with external spline teeth provided at an outer periphery of the camshaft. An engaging portion is provided at one of the inner periphery of the sleeve and the outer periphery of the camshaft, and is configured to retractably project toward the other one of the inner periphery of the sleeve and the outer periphery of the camshaft. A latching portion is provided at the other one of the inner periphery of the sleeve and the outer periphery of the camshaft. The sleeve has a through-hole that is provided at the same position in a circumferential direction as the engaging portion to supply the inner periphery of the sleeve with lubricating oil.

A control device has two modes as control modes of an electric power supply to an electromagnetic solenoid, which are used when a first determining unit determines that a difference between a sensed value of a phase and a target value of the phase exceeds a permissible range. One of the modes is a special mode that is used when a second determining unit determines that the sensed value of the phase reaches a threshold value. Another one of the modes is a normal mode that is used when the second determining unit determines that the sensed value of the phase does not reach the threshold value. In the special mode, the control device controls supply of the electric power to the electromagnetic solenoid in such a manner that an opening degree of an advancing port is larger than the opening degree of the advancing port in the normal mode.

Variable valve timing apparatus

A variable valve mechanism includes a first cam unit including cams configured to drive an intake valve on a first side in a first cylinder; a first sliding mechanism configured to slide the first cam unit such that the first cam unit is switched between two positions to select any one of the cams; a second cam unit including cams configured to drive an intake valve on a second side in the first cylinder, cams configured to drive an intake valve on the first side in a second cylinder, and cams configured to drive an intake valve on the second side in the second cylinder; and a second sliding mechanism configured to slide the second cam unit such that the second cam unit is switched among three positions to select any one of the cams for each of the intake valves.

Variable valve mechanism

A variable valve mechanism includes a cam shaft, a cam unit, a guide portion and a shift pin. The guide portion includes a guide plate provided on an outer periphery of a cam unit, a first stopper and a second stopper. The guide plate is pivotally supported at a first part such that a second part of the guide plate is inclined toward a first side or a second side. The first and second stoppers abut with the second part from the first side and the second side, respectively, so as to hold the second part at a first position and a second position, respectively. The first part includes two arms projecting toward the first side and the second side. The two arms are configured to swing the guide plate.

In a variable valve mechanism, a guide groove includes guide portions provided on respective side surfaces of the guide groove in a width direction, the guide portions projecting so as to face each other; a cam unit is slid toward a first side by relatively moving a shift pin toward a second side with use of the guide portion on the first side, and the cam unit is slid toward the second side by relatively moving the shift pin toward the first side with use of the guide portion on the second side; the guide portion on the first side is provided in an immovable piece, and the guide portion on the second side is provided in a movable piece; the movable piece is displaceable between a first position and a second position: and a first urging member configured to urge the movable piece toward the first position is provided.

In a variable valve actuation apparatus for an internal combustion engine, a rotor of a variable valve timing mechanism is fixed to one end of a camshaft by a plurality of bolts. An oil control valve configured to control hydraulic pressure that acts on the rotor is fixed to the rotor by one or some of the plurality of bolts. For this reason, by releasing fastening of the bolt that fixes the oil control valve to the rotor among the plurality of bolts that fix the rotor to the one end of the camshaft, the oil control valve is allowed to be removed from the rotor while the rotor is fixed to the camshaft. Therefore, it is not required to perform positioning for fixing the rotor to the camshaft at the time of replacement of the oil control valve.

Variable valve actuation apparatus for internal combustion engine

The present valve mechanism for an internal combustion engine makes it possible to reliably perform switching between the low-velocity operation mode and the high-velocity operation mode without delay. The valve mechanism includes: a first rocker arm which is supported by a rocker shaft in an oscillatory manner; a second rocker arm which is supported by the rocker shaft in an oscillatory manner; a cylinder provided for either said first rocker arm or said second rocker arm, said cylinder communicating with an oil passage; a first piston fitted in said cylinder in a slidable manner; an engaging protrusion provided in a protruding condition for the remaining one of said first rocker arm and said second rocker arm, said engaging protrusion being capable of engaging with said first piston; and a second piston which moves said first piston to an engaging position.

Valve mechanism for internal combustion engine

There is provided a combustion chamber structure in an internal combustion engine in which, at a peripheral portion of a combustion chamber, a gap between a cylinder head lower face and a piston upper face is small in intake-to-intake and exhaust-to-exhaust zones and gradually increases toward an intake-to-exhaust zone. According to such design, the mixture in the peripheral portion of the combustion chamber can smoothly flow from the intake-to-intake and exhaust-to-exhaust zones to the intake-to-exhaust zone along the peripheral face of the cylinder. The flow of air-fuel mixture from the intake-to-intake zone collides at the center of the intake-to-exhaust zone with the flow of mixture from the exhaust-to-exhaust zone, and the combined flow goes over a conical tapered portion in the upper face of the piston and vigorously enters a central recessed portion thereof. Therefore, it is possible to satisfactorily mix an air-fuel mixture with a simplified configuration.

Growing community of inventors

Okazaki, Japan

Yu Yokoyama