Otics Corporation

Toyota Jidosha Kabushiki Kaisha

Fuji Jukogyo Kabushiki Kaisha

Koki Yamaguchi

Naoki Hiramatsu

Masatoshi Sugiura

Akira Sugiura

Takayuki Maezako

Motohiro Yuge

Masaaki Tani

Hiroyuki Suzuki

Shinichiro Kikuoka

Masahide Sakurai

Junichi Ookawara

Dan Nagano

Naoki Hiramutsu

A variable valve mechanism includes a rocker arm including a first input arm, a second input arm, and an output arm, and a switch device that switches an operating state to a first state by coupling only the first input arm to the output arm, and switches the operating state to a second state by coupling only the second input arm to the output arm. The switch device includes two pins that are displaceably placed in the rocker arm and contact each other at their end faces, and a displacement device that switches the operating state to the first state by displacing a contact portion between the two pins to between the output arm and the second input arm, and switches the operating state to the second state by displacing the contact portion between the two pins to between the output arm and the first input arm.

Variable valve mechanism of internal combustion engine

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.

A variable valve mechanism includes an input arm that axially supports a roller pressed by a cam, via a roller pin, an output arm that drives a valve when swinging, a switch device that switches the variable valve mechanism between a coupled state where the both arms are coupled and an uncoupled state where the arms are uncoupled from each other, and a lost motion spring that biases the roller against the cam when in the uncoupled state. The lost motion spring includes an extended portion extending in an inter-arm clearance between the input arm and the output arm. An end of the roller pin projects from the input arm into the inter-arm clearance by such a length that the end is accommodated in the inter-arm clearance and that allows a spring retaining portion to be formed in the end. The spring retaining portion is formed in the end.

A variable valve mechanism includes a variable arm including a first arm and a second arm. The second arm is pivotally supported so as to be swingable by a support shaft. A position of the support shaft is a position where, during a base circle phase, in side view, a second segment connecting an axis of a roller to an axis of the support shaft is longer than a first segment connecting the axis of the roller to an axis of a camshaft, and an angle of the second segment formed with respect to a third segment connecting the axis of the roller to a swing axis of a roller arm is 60&#xb0; to 120&#xb0; toward the camshaft. The second arm extends from the support shaft such that a distal end portion of the second arm protrudes in between a cam and the roller.

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.

A variable valve mechanism that is downsized by providing a crank mechanism in place of an egg-shaped cam on an input shaft that is rotationally driven by a crankshaft of an internal combustion engine. A variable valve mechanism () having a variable mechanism () that changes the opening/closing amount of a valve (), includes an input shaft () that is rotationally driven by an internal combustion engine. The input shaft () is provided with a crank mechanism () that is connected to the variable mechanism () and converts the rotational motion of the input shaft () into reciprocating motion for opening and closing the valve ().

Variable valve mechanism

The present invention provides a variable valve mechanism which includes a camshaft having a drive cam, a rocker shaft provided parallel to the camshaft, and a variable mechanism that is provided on the rocker shaft and interposed between the drive cam and a valve, and that changes an opening/closing amount of the valve. The variable mechanism includes a main arm that engages with the drive cam, a cam arm that has a cam surface pressing the valve, a control cam that is provided on the rocker shaft, and has an outer peripheral surface whose distance from a shaft center of the rocker shaft varies gradually, and a displacement member whose distance from the shaft center is changed by turning of the control cam. A relative phase between the main arm and the cam arm is displaced as the distance between the displacement member and the shaft center changes.

Growing community of inventors

Nishio, Japan

Koki Yamaguchi