Denso Corporation

Nippon Soken, Inc.

Kinya Takahashi

Jun Yamada

Masayasu Ushida

Takao Nojiri

Futoshi Kawamura

Seiji Yaoko

Seiji Yaokou

Tomonari Chiba

Makoto Otsubo

Tomonori Suzuki

Eiji Isobe

Tetsuro Mitsutani

Takuya Hamada

Koji Kuroda

Tatsuhiko Imaizumi

Hikaru Kokumai

Tomonobu Ikuma

Mitomu Mohri

A hydraulic oil control valve includes a sleeve, a spool and a spring. The spool is received at an inside of the sleeve and is configured to be reciprocated. The spring is configured to be seated against a spring seat of the sleeve and is configured to apply a preload to the spool. The sleeve has a stepped portion, which has a spool contact surface for limiting movement of the spool toward the spring seat, and a protrusion, which is located at a center of the spring seat and protrudes toward an opening of the sleeve. The protrusion has a sloped peripheral surface. The protrusion is configured such that in a state where an end portion of the spring is not seated against the spring seat while the spring is placed adjacent to the spring seat, the end portion of the spring contacts the protrusion.

Hydraulic oil control valve and valve timing adjustment device

A valve timing adjustment device includes a hydraulic oil control valve. The hydraulic oil control valve includes: an outer sleeve that is shaped in a tubular form and has a projection at an outer periphery of the outer sleeve; an inner sleeve that is located on an inner side of the outer sleeve; and a spool that is located at an inside of the inner sleeve. A reference-shape portion, which serves as a reference at a time of positioning the outer sleeve relative to the inner sleeve, is formed at an outer periphery of the projection. A seat surface of the projection, which fixes a vane rotor between the seat surface of the projection and an end portion of one of a drive shaft and a driven shaft, is shaped in a rotationally symmetric form that is rotationally symmetric around a rotational axis.

Valve timing adjustment device

A hydraulic oil control valve, which is placed along a rotational axis of a valve timing adjusting device, includes a sleeve and a spool configured to slide in an axial direction on an inner side of the sleeve in a radial direction. The sleeve includes: an inner sleeve that has an opening in which a distal end portion of the spool is inserted; and an outer sleeve. In a state where the spool is positioned farthest from an actuator, the distal end portion projects from the opening toward a side that is opposite to the actuator.

Hydraulic oil control valve and valve timing adjusting device

A check valve is made of a resilient body wound in a ring form and is located in an annular flow passage. A displacement limiter includes: a limiter main body that is located on an outer side of the check valve and is configured to limit displacement of the check valve in a diameter increasing direction of the check valve; and a limiter flow passage that communicates between one side and the other side of the limiter main body in an axial direction to enable hydraulic oil to flow between the one side and the other side of the limiter main body through the limiter flow passage.

Fluid control valve, and valve timing adjusting device employing same

In a valve timing adjusting device, a vane rotor includes a second supply oil passage connectable to a first supply oil passage of a second shaft. A check valve is provided between the vane rotor and the second shaft, and permits a flow from the first supply oil passage toward the second supply oil passage and prevents a flow from the second supply oil passage toward the first supply oil passage. A fixing unit is provided between the check valve and the second shaft, and fixes the check valve between the fixing unit and the vane rotor. The fixing unit includes a third supply oil passage which connects the first supply oil passage and the second supply oil passage. A filter is provided for the fixing unit and can capture foreign substances flowing through the third supply oil passage.

Valve timing adjusting device

A first one-way valve is provided in a first advance passage connecting a hydraulic pump to a control advance chamber. A second one-way valve is provided in a first retard passage connecting the hydraulic pump to a control retard chamber. A first control valve is provided in a second advance passage to bypass the first one-way valve for communication of the first advance passage. A second control valve is provided in a second retard passage to bypass the second one-way valve for communication of the first retard passage. The first control valve operates by the pilot pressure to close the second advance passage at advance controlling and opening it at retard controlling. The second control valve operates by the pilot pressure to close the second retard passage at retard controlling and open it at advance controlling.

Valve timing controller

A first-side check valve prevents a hydraulic fluid from being discharged out of a retard chamber, and a second-side check valve prevents the hydraulic fluid from being discharged out of an advance chamber. A first-side control valve opens or closes a first-side discharge passage by a pilot pressure received through a retard pilot passage. A second-side control valve opens or closes a second-side discharge passage by the pilot pressure received through an advance pilot passage. Another check valve is disposed in a supply passage between a phase switch valve and a branch point, at which a supply passage is branched.

Valve timing control system

A phase control valve, which supplies a drive hydraulic pressure to an advance chamber or a retard chamber, is integrated with a drain switch valve, which controls opening and closing of an advance drain control valve and opening and closing of a retard drain control valve, to form a solenoid spool valve. The advance drain control valve is provided in an advance check valve bypass passage, which bypasses an advance check valve, and is driven by a pilot hydraulic pressure to open and close the advance check valve bypass passage. The retard drain control valve is provided in a retard check valve bypass passage, which bypasses a retard check valve, and is driven by a pilot hydraulic pressure to open and close the retard check valve bypass passage.

One of retard passages, which supplies working fluid to one of retard chambers, is a dedicated passage. The other remaining retard passages, which supply the working fluid to the other remaining retard chambers, are branch passages, which are branched from a retard passage that serves as a supply passage. With this construction, a flow quantity of working fluid per unit time supplied from the one of retard passages to the one of retard chambers becomes larger than a flow quantity of working fluid per unit time supplied from the other remaining retard passages to the other remaining retard chambers. Thus, the one of retard chambers can be filled with the working fluid earlier than the other remaining retard chambers.

A valve timing adjusting apparatus has a housing and a vane rotor to form multiple fluid chambers, and a relative position of the vane rotor to the housing is adjusted by the fluid pressure supplied into the fluid chambers. A check valve is provided in a branched passage portion, so that working fluid may not be pushed out from an advancing fluid chamber to a low pressure side, even when the working fluid in the advancing fluid chamber is temporally compressed to increase its fluid pressure due to a torque change applied from a cam shaft to the vane rotor.

Valve timing adjusting apparatus

A valve timing adjusting apparatus for an engine comprises a housing unit and a vane rotor rotatably housed in the housing unit. The housing unit comprises a front plate, a shoe housing and a sprocket, wherein those elements are fixed to each other. A position determination pin is inserted through a through hole formed in the shoe housing and into a tapered hole formed in the sprocket, to position the shoe housing at a desired position with respect to the sprocket. Since a forward end of the position determination pin is brought into contact with an inner surface of the tapered hole, the positioning of the shoe housing with respect to the sprocket can be surely attained.

A shoe housing receives a driving force from a crankshaft and a vane rotor rotates with a camshaft in combination. The vane rotor is received in the shoe housing in such a way as to freely turn. Each of the vanes of the vane rotor partitions each of three receiving chambers into a retard hydraulic chamber and an advance hydraulic chamber. A check valve is disposed in an advance supply passage. The check valve allows a working oil to flow from an oil pump through the advance supply passage to the advance hydraulic chamber and prohibits the working oil from flowing back from the advance hydraulic chamber through the advance supply passage to a drain.

A valve timing adjusting apparatus comprises a first rotating body adjusting the opening/closing timing of the intake valves, and a second rotating body adjusting the opening/closing timing of exhaust valves. A first and a second driving force transmitting members respectively have first and second endless members for power transmission. The peripheral shape of the second rotating body comprises a circumferential shape portion and cutoff shape portions whose distance from the center of rotation is smaller than the circumferential shape portion's. When the first and second rotating bodies are assembled to an internal combustion engine, the cutoff shape portions are positioned in such a rotation angle position that the first endless member for power transmission can be inserted into the gap between the first and second rotating bodies.

A valve timing control device for adjusting the timing of opening a valve of an internal combustion engine includes a torsion spring having one end engaged with a shoe housing and the other end engaged with a vane rotor to urge the vane rotor, relative to the shoe housing, toward the advancing side or the delaying side. The end of the torsion spring engaged with the vane rotor is rotatable together with the vane rotor and inwardly directed in the radial direction, referencing the torsion spring. The vane rotor has a hook groove with which the inwardly-directed end of the torsion spring is engaged. Thus, a driven member having the vane rotor can be made smaller. Also, there is no need to form the hook groove inside the vane, so vane strength is not compromised and sealing with the vane is attained.

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Obu, Japan

Kinya Takahashi