Hitachi, Ltd.

Unisia Jecs Corporation

Atsugi Motor Parts Company, Limited

Nissan Motor Company Limited

Takanori Sawada

Seiji Suga

Isao Hayase

Seiji Tsuruta

Atsushi Watanabe

Akio Akasaka

Nobutaka Hayashi

Seinosuke Hara

Makoto Kano

Shinichi Takemura

Masahiko Watanabe

Shoji Morita

Tomoya Tsukada

Toshiro Ichikawa

Osamu Fujita

Yoshinori Ichinosawa

Atsushi Ehira

Yasuo Fukuda

Keiji Hisahara

A parallel guide portion as an integral structure of a sprocket and a vane, as well as a slant guide portion, are arranged alternately on the same circumference, with circumferential gaps being formed between said guide portion and the parallel guide portion, said guide portion having a shape such that the circumferential gaps become smaller in one axial direction of a cam shaft. Wedge members are disposed in the circumferential gaps respectively and are moved in one axial direction to fill up the circumferential gaps, thereby fixing the phase between the sprocket and the vane into a locked state. The wedge angle of each wedge member is set sufficiently small and, by utilizing varying torques acting on the cam shaft, said members are each moved and locked in one axial direction with a spring. Said members are actuated in an opposite axial direction with oil pressure to release the locked state, thereby permitting a phase angle control. By utilizing a varying torque acting on the cam shaft, the phase of the cam shaft is returned for itself to an intermediate position and is locked without looseness.

Phase controller and cam shaft phase controller for internal combustion engine

A hydraulic control system for an internal combustion engine, includes a driven mechanism driven by hydraulic pressure fed through a flowing passage change-over valve. The flowing passage change-over valve includes a valve body formed with a plurality of ports which are respectively communicated with the supply passage and the oil passage, and a spool valve body slidably disposed in the valve body to open and close the plurality of ports, the ports including a supplying port communicated with the supplying passage. The maximum cross-sectional area of the supplying port is larger than a minimum cross-sectional area of the supplying passage. The flowing passage change-over valve is supplied with electric current to heat hydraulic fluid kept in the flowing passage change-over valve so as to lower a viscosity of the hydraulic fluid.

Hydraulic control system for internal combustion engine

A variable valve timing control system of an internal combustion engine includes a hydraulically-operated phase converter disposed between a sprocket and a camshaft, and having a phase-advance hydraulic chamber and a phase-retard hydraulic chamber for changing an angular phase of the camshaft relative to the sprocket. An electric pump is provided to supply working fluid selectively to one of the hydraulic chambers via a directional control valve. Also provided is a check valve disposed in a discharge line of the pump for permitting flow in a direction that the working fluid flows from the pump to the directional control valve and preventing any flow in the opposite direction, so as to prevent a pulse pressure arising from alternating torque exerted on the camshaft from being transmitted from either one of the hydraulic chambers via the discharge line to a discharge port of the pump.

Variable valve timing control system of internal combustion engine

The invention intends to improve a response by utilizing a rotational variable torque of a cam shaft. Communication paths respectively communicating an advance hydraulic chamber and a retard hydraulic chamber provided in a second rotary member and a hydraulic connecting passage are provided so as to be communicated, at a time when a control member intending to improve a response by moving a phase angle control slider in an axial direction or a rotational direction in correspondence to an operating state such as an advance, a retard or the like so as to intermittently communicate an advance chamber communication path and a retard chamber communication path with a hydraulic chamber connecting groove only in a section in which a cam shaft variable torque in an operating direction is applied, is controlled in a rotating region, and a relative rotation of a third rotary member and the second rotary member stops.

Valve timing control apparatus

Engine valve actuating devices

A variable valve actuation apparatus for engine cylinder valves comprises a main rocker arm having an end portion for driving association with a cylinder valve. The main rocker arm supports a sub-rocker arm. A lost motion mechanism is between the main rocker and sub-rocker arms. The main rocker arm is formed with a plunger seat. The plunger seat includes a bearing surface on which a plunger of the lost motion mechanism rests. Further, the plunger seat includes gutters for discharging lubricant oil.

Variable valve actuation apparatus

An cylinder valve controlling apparatus comprises a first rocker arm and a second rocker arm cooperating with a middle lift cam and a low lift cam, respectively, to active two cylinder valves arranged for each of the engine cylinders, respectively. The apparatus further comprises a free rocker arm cooperating with a high lift cam. During engine operation at low speeds, the first rocker arm activates one of the cylinder valves in accordance with the profile of the middle lift cam, while the second rocker arm activates the other cylinder valve in accordance with the profile of the low lift cam. During engine operation at middle speeds, a coupling including a first lever establish drive connection between the first and second rocker arms and thus the first and second rocker arms follow the profile of the middle cam. During engine operation at high speeds, with the first-mentioned coupling maintaining the drive connection, another coupling establishes drive connection between the free cam follower and the first rocker arm. Thus, the first and second rocker arms activate the corresponding cylinder valves in accordance with the profile of the high lift cam.

Engine cylinder valve controlling apparatus

A main rocker arm is supported for swinging motion to operate one of the intake and exhaust valves of an internal combustion engine. A high-speed rocker arm is supported on the main rocker arm for swinging motion according to rotation of a high-speed cam rotating in synchronism with engine rotation. The high-speed rocker arm has a slip surface for engagement with the high-speed cam. The high-speed rocker arm is drivingly connected to the main rocker arm for swinging motion in unison with the main rocker arm when the engine is operating at a high speed. The driving connection is released to permit swinging motion of the main rocker arm according to rotation of a low-speed cam independently of the swinging motion of the high-speed rocker arm when the engine is operating at a low speed. The slip surface of the high-speed rocker arm is made of an alloy tool steel having carbide deposited and dispersed to provide a hardness of HRC55 or more to the slip surface. A hard coat is formed through physical vapor deposition on the slip surface of the high-speed rocker arm.

Valve operating apparatus

An intake- and/or exhaust-valve timing control system for internal combustion engines in which a ring gear mechanism is provided between a timing pulley and a cam shaft for adjusting the phase angle between the pulley and the cam shaft. A drive mechanism is also provided for driving the ring gear mechanism depending upon the operating state of the engine. The drive mechanism includes a hydraulic circuit having oil supply and exhaust passages, a flow control valve having a spool valve for controlling the amount of working fluid flowing through the hydraulic circuit, a controller for monitoring the operating state of the engine, and an electromagnetic actuator having a plunger rod for actuating the flow control valve in response to the control signal from the controller. The flow control valve and the actuator are integrally mounted in the cylinder head. Therefore, relative friction between the facing ends of the spool valve and the plunger rod is avoided.

Intake- and/or exhaust-valve timing control system for internal

A valve timing adjusting mechanism houses a timing adjusting gear assembly within a liquid-tight housing which prevents working fluid used to adjust the timing from coating a timing gear engaging a timing belt. The working fluid is introduced within the housing to exert timing adjusting force on the timing adjusting mechanism, resulting in relative angular displacement between a camshaft and the timing gear which is manifested as an adjustment to the valve timing. With this arrangment, the timing belt is free of working fluid. Therefore, the lifetime of the belt retains its design value and slip between the timing belt and the timing gear can be prevented.

Growing community of inventors

Kanagawa, Japan

Takanori Sawada