Otics Corporation

Toyota Jidosha Kabushiki Kaisha

Nakanishi Metal Works Co., Ltd.

Naoki Hiramatsu

Koki Yamaguchi

Masatoshi Sugiura

Masahide Sakurai

Takayuki Maezako

Motohiro Yuge

Akira Sugiura

Masaaki Tani

Tomoki Miyoshi

Shinichiro Kikuoka

Kimihiko Todo

Akira Takeuchi

Eiichi Nozaki

Yoshio Kawatake

Tomiyasu Hirano

Toshimasa Sasaki

Naoyuki Yamamoto

Sugiura Masatoshi

A variable valve mechanism includes a first member and a second member which are disposed between a cam and a valve, a switch pin that is displaced to connect and disconnect the first member to and from the second member, and a displacement device. The displacement device includes a ring-shaped plate that is fitted on a camshaft of the cam so as to be co-rotatable with the camshaft and slidable in a longitudinal direction of the camshaft and that has one side surface configured to contact the switch pin and has the other side surface including a tapered surface formed so that a plate thickness increases toward a rotational direction, and a support device formed by a support pin and a moving device that moves the support pin to a position where the support pin contacts the tapered surface and a position not contacting the tapered surface.

Variable valve mechanism of internal combustion engine

A variable valve mechanism includes a first cam and a second cam, a main arm that drives a valve when swinging, a first sub arm that swings when pressed by the first cam, a second sub arm that swings when pressed by the second cam, and a switch device. The switch device includes a first switch pin that moves between a first coupled position between the main arm and the first sub arm and a first uncoupled position, and a second switch pin that moves between a second coupled position between the main arm and the second sub arm and a second uncoupled position. Both switch pins are arranged so as to be displaced from each other in positions where these switch pins do not overlap at least during a base circle phase in which base circles of both cams act.

A variable valve mechanism of an internal combustion engine includes a cam, a transmission mechanism, a first variable device that controls the transmission mechanism to continuously change at least a maximum lift amount of a lift curve indicating a lift amount of a valve that corresponds to a rotation angle of the internal combustion engine, and a second variable device that controls the transmission mechanism to continuously change at least an operation angle of the lift curve. When the lift curve lies in any condition within a predetermined range that covers all or part of a variable range of the lift curve, an absolute value of a ratio of a maximum lift amount variation to an operation angle variation for a slight change from the condition caused by the first variable device is larger than that for a slight change from the condition caused by the second variable device.

In a variable valve mechanism of an internal combustion engine, when a slider is displaced relative to an input member and an output member in an axial direction, the output member turns relative to the input member in a swing direction, whereby a lift of a valve is increased or reduced. The variable valve mechanism is brought into a lift retaining state when the slider is placed in an idle running range located on a reducing direction side with respect to a boundary position. The lift retaining state is a state where when the slider is displaced in the axial direction, the input member and the output member are displaced together with the slider in the axial direction, so that the relative displacement of the slider and the relative turning of the output member do not occur and the lift of the valve is retained.

The present invention provides a variable valve mechanism of an internal combustion engine, which includes an input member, an output member, a slider and a variable device. The output member has internal space formed therein and has a first cutout and a second cutout which are formed at two positions separated from each other in the swing direction so as to extend from an outer periphery of the output member to the internal space, and the input member is mounted in the internal space so as to extend through both inner sides of the first and second cutouts, and is brought into contact with inner side surfaces of the cutouts from both sides in the thrust direction, whereby relative displacement of the input member together with the slider in the thrust direction with respect to the output member is restricted at two positions by the first and second cutouts.

A variable valve mechanism of an internal combustion engine includes a plurality of swing members and a variable device that displaces a control shaft to displace a plurality of slider gears of the swing members at a time, thereby changing valve lifts of the plurality of swing members at a time by meshing of helical splines. The swing members include a first swing member for a predetermined cylinder of a plurality of cylinders and a second swing member for a cylinder other than the predetermined cylinder, and a helix angle of the helical splines varies between the first and the second swing members. The variable device displaces the control shaft to a predetermined normal position to perform a normal operation, and displaces the control shaft to a predetermined cylinder cutoff position to perform a cylinder cutoff operation in which the second swing member does not drive a valve.

The present invention provides a variable valve mechanism of an internal combustion engine, which includes a rocker arm that includes a roller arm including a roller that rotatably abuts against a cam and a side arm provided at a side of the roller arm and that drives a valve, and a switching device that includes a switching pin and a hydraulic chamber provided inside the rocker arm and that switches a drive state of the valve by displacing the switching pin between a coupling position at which the switching pin extends between the roller arm and the side arm and a non-coupling position at which the switching pin does not extend between the roller arm and the side arm based on variations in hydraulic pressure in the hydraulic chamber. The switching pin is provided on an axis of the roller, and the hydraulic chamber is provided inside the roller arm.

The present invention provides a variable valve mechanism of an internal combustion engine, which includes a rocker arm that is swingably supported by a single pivot, and a switching device that operates the rocker arm to switch a drive state of the valve, in which the rocker arm is configured such that at least in a predetermined drive state, a pressing force of the cam is applied disproportionately to one side of the rocker arm in a width direction with respect to a center line when the cam presses a portion of the rocker arm located away from the center line in the width direction. The variable valve mechanism further includes a swing guide that abuts against the rocker arm so that the rocker arm is guided in a swing direction so as not to be tilted in the width direction.

The present invention provides a variable valve mechanism, which includes a rocker arm including an input member and an output member; a switching device that switches a drive state of the valve by displacing the switching pin between a coupling position at which the switching pin extends between the first pinhole in the input member and the second pin hole in the output member and a non-coupling position at which the switching pin does not extend; and a lost motion spring. A displacement clearance is formed between an inner peripheral surface of the first or second pin hole and an outer peripheral surface of the switching pin to permit the relative displacement in a range of the displacement clearance at a coupled time so that a tappet clearance is not formed with the input member urged toward the cam by the lost motion spring.

The present invention provides a variable valve mechanism of an internal combustion engine which includes a main arm that is capable of swinging and that drives a valve when swinging, a first sub arm that is provided on one side in the lateral direction of the main arm and that swings when driven by a first cam, a second sub arm that is provided on the other side in the lateral direction of the main arm and that swings when driven by a second cam, and a switch device that performs switching between a first coupled state where only the first sub arm of the first and second sub arms is coupled to the main arm, and a second coupled state where only the second sub arm of the first and second sub arms is coupled to the main arm.

The present invention provides a variable valve mechanism of an internal combustion engine, which includes a main arm having at a rear end thereof a supported portion that is continuously supported swingably by a support member without floating upward, a sub arm which has a tip end to which a roller contacting a cam is rotatably attached, in which a center of the roller is located rearward of the pressing portion and forward of a swing center of the supported portion, which has a rear end that is swingably supported with respect to the main arm by a support pin, and in which a center of the support pin is located rearward of the center of the roller and forward of the swing center of the supported portion, and a switch pin that is inserted in a central portion of the roller.

The present invention provides a variable valve mechanism of an internal combustion engine which includes a rotary cam, an output arm, an input member, and a switching device that switches between a coupled state and a non-coupled state. The variable valve mechanism changes a drive state of the valve by the switching operation. The input member includes an annular input roller that contacts the rotary cam, and a swing pin that is inserted into the input roller so as to rotatably support the input roller and that swings relative to the output arm when in the non-coupled state. A center of the relative swinging movement is located at a position different from a rotation center of the input roller which is located inward of the input roller.

Variable valve mechanism

A vehicle engine includes: a cylinder head; a cam housing fixed to a top of the cylinder head; a cam cap fixed to a top of the cam housing; a camshaft rotatably supported between the cam housing and the cam cap, the camshaft supporting a cam; a rocker arm configured to be pushed by the cam; and a valve configured to operate by being pushed by the rocker arm; and an oil pipe that is formed integrally with the cam cap. Lubricant oil is supplied through the oil pipe to a contact point between the cam and the rocker arm.

Vehicle engine

A vehicle engine includes a cylinder head, a cam housing fixed to a top of the cylinder head, a cam cap fixed to a top of the cam housing, a camshaft rotatably supported between the cam housing and the cam cap, the camshaft supporting a cam, a rocker arm configured to be pushed by the cam, and a valve configured to operate by being pushed by the rocker arm. The vehicle engine has an oil pipe that is formed integrally with the cam housing.

A rocker arm unit constituting a valve gear includes a support member, a rocker arm including a roller and walls opposed to each other with the roller being interposed between them and a wire member bridging the support member side and the rocker arm side with each other. The walls have shaft holes into which both ends of a shaft member rotatably supporting the roller extend respectively. The walls have lengthwise ends connected to each other via a receiving portion supported on a top of the support member so that the rocker arm is swung. The wire member has an extending portion extending from the support member side to the rocker arm side and having a distal end. The rocker arm side includes a part located away from the receiving portion. The distal end of the extending portion serves as an engagement portion engaging the rocker arm side part.

Growing community of inventors

Nishio, Japan

Naoki Hiramatsu