Denso Corporation

Ryo Ishibashi

Akira Takagi

Takumi Sugiura

Motoyoshi Ando

Kanehisa Nagasaki

Hirohisa Noda

Motoyoshi Andoh

Hiroo Tsujimoto

A housing is placed at an inside space of a case to be installed on a vehicle. The housing includes: a housing plate portion configured to contact a case plate portion of the case; and a receiving space located on one side of the housing plate portion which is opposite to the case plate portion. An electric motor is placed at the receiving space and is configured to output a torque. The housing includes: a housing ventilation hole that extends through the housing plate portion and communicates between an outside space of the housing and the receiving space; and a breathable filter that is placed on a side of the housing ventilation hole, at which the case plate portion is placed, to cover the housing ventilation hole, while the breathable filter is configured to perm it a gas to pass through the breathable filter.

Clutch actuator

A speed reducer is configured to reduce a rotational speed of rotation generated by torque received from a drive device and output the torque of the rotation of the reduced rotational speed. A drive cam has a plurality of drive cam grooves formed at one end surface of the drive cam and is rotated by the torque outputted from the speed reducer. A driven cam has a plurality of driven cam grooves formed at one end surface of the driven cam while each of the plurality of rolling elements is clamped between a corresponding one of the plurality of drive cam grooves and a corresponding one of the plurality of driven cam grooves. At least a part of each of the plurality of drive cam grooves overlaps with the speed reducer in the axial direction.

Clutch device

A normal-time drive cam groove extends from a drive cam specific point, which is defined as a specific point of the drive cam, toward one side in a circumferential direction of the drive cam. A groove bottom at the normal-time drive cam groove is sloped relative to one end surface of the drive cam such that a depth of the groove bottom continuously decreases from the drive cam specific point toward the one side in the circumferential direction of the drive cam. An emergency-time drive cam groove extends from the drive cam specific point toward another side in the circumferential direction of the drive cam.

At a drive cam slope groove, a groove bottom is sloped relative to one end surface of a drive cam such that a depth of the groove bottom continuously decreases from one side toward other side in a circumferential direction. At a drive cam planar groove, the groove bottom is parallel to the one end surface of the drive cam. A drive cam connection groove has: one end connected to an end of the drive cam slope groove located on the other side in the circumferential direction of the drive cam; and the other end connected to an end of the drive cam planar groove located on the one side in the circumferential direction. A slope angle of the groove bottom relative to the one end surface of the drive cam continuously changes from the one end to the other end of the drive cam connection groove.

Rolling element cam and clutch device using same

Torque of a prime mover is input into a sun gear. A planetary gear revolves in a circumferential direction of the sun gear while rotating and meshing with the sun gear. A carrier has an annular shape, rotatably supports the planetary gear, and is rotatable relative to the sun gear. A first ring gear is fixed to a housing, and meshes with the planetary gear. A second ring gear meshes with the planetary gear, is different from the first ring gear in number of teeth of a tooth portion, and outputs torque to a rotation portion. At least a part of the sun gear in an axial direction is located radially inward of the carrier. At least a part of the first ring gear and at least a part of the second ring gear in the axial direction are located radially outward of the carrier.

A state changing unit is capable of contacting a clutch, and being configured to receive a force along the axial direction from a translation portion and change a state of the clutch to an engaged state or a disengaged state according to a position of the translation portion in an axial direction relative to a housing. A fixed end is non-rotatable relative to the housing. A return spring is disposed on a side of the fixed end opposite to the clutch, and capable of urging the translation portion in a direction away from the clutch with respect to the fixed end.

A housing includes an accommodation space for a prime mover and a speed reducer. A rotational translation unit includes a rotation portion that rotates relative to the housing upon receiving torque outputted from the speed reducer, and a translation portion that moves relative to the housing in an axial direction according to rotation of the rotation portion. The accommodation space is between the rotation portion and the housing. A clutch in a clutch space allows or interrupts transmission of torque between a first transmission portion and a second transmission portion. The rotation portion is between the clutch space and the accommodation space. A sealing member has an annular shape in contact with the rotation portion, and maintains an air-tight or liquid-tight state between the accommodation space and the clutch space.

In a method for setting a command-response characteristic of an oil pressure control apparatus for each oil temperature, the command-response characteristic actually measured at a reference oil temperature is treated as a reference I-P characteristic. Then, a stroke-response characteristic is calculated based on the reference I-P characteristic, a thrust-force correlation and a restoring-force correlation. An overlapping length and a clearance width of overlapping areas between a sleeve and a spool of the oil pressure control apparatus are estimated based on the reference I-P characteristic and the stroke-response characteristic. Finally, the command-response characteristics for each oil temperature are decided and set based on the overlapping length and the clearance width.

Oil pressure control apparatus and method for setting oil-pressure characteristic

A linear solenoid includes a plunger to slide in an axis direction, and a stator core. The plunger includes a magnetic base, and a nonmagnetic plating layer defined on the magnetic base. The stator core has a first blocker arranged between a first magnetic core and a second magnetic core. The second magnetic core has a second blocker distanced from the first blocker in the axis direction. Each of the blockers limits a magnetic reaction. The plunger directly slides on an inner circumference face of the stator core at only two sections corresponding to the first and second blockers.

Linear solenoid

In an electromagnetic hydraulic pressure control valve of an N/L type, an electromagnetic actuator provides a force to a spool, which is slidably received in a valve housing, in a valve opening direction for opening an input port of the valve housing. A return spring provides a force to the spool in the valve closing direction. A constriction is provided to constrict a flow passage cross sectional area in a fluid passage, which extends from the input port to a hydraulic servo. A negative pressure port opens in a direction generally perpendicular to a flow direction of a fluid at a location, at which a fluid velocity of the fluid is accelerated by the constriction. A negative pressure guide passage communicates between the negative pressure port and a feedback chamber defined in the valve housing.

Fluid pressure control apparatus

A spool valve includes a valve housing, a spool and radial damper device. The valve housing has a shaft bore. The spool is slidably supported within the shaft bore in a longitudinal direction, and the spool has a first diameter portion and a second diameter portion. The radial damper device has a radial damper chamber and a radial chamber restrictor. The radial damper chamber is defined by a diameter difference between the first diameter portion and the second diameter portion. The radial chamber restrictor provides communication between the radial damper chamber and an adjacent chamber disposed adjacent to the radial damper chamber in the longitudinal direction.

Spool valve

A solenoid includes a stator core, a plunger, a ring core, and a magnetic circuit component. The stator core has a fixed axial end and a free axial end. The free axial end is unfixed. The stator core is formed of a magnetic material. The plunger is slidable along an inner surface of the stator core. The plunger is formed of a magnetic material. The ring core surrounds an outer surface of the free axial end of the stator core. The ring core is formed of a magnetic material. The magnetic circuit component is adjacent to the stator core. The magnetic circuit component conducts magnetic flux with the stator core. The ring core radially conducts radial magnetic flux with the stator core. The ring core axially conducts axial magnetic flux with the magnetic circuit component.

Growing community of inventors

Kariya, Japan

Ryo Ishibashi