Jtekt Corporation

Takuya Tsuda

Junji Ando

Hiroyuki Ando

Kunihiko Suzuki

Kazutaka Matsukawa

Kenji Kushizaki

Akinao Minegishi

Hiroshi Shirayanagi

Shuichi Takahashi

Kiyoyuki Hattori

A vehicle differential gear includes first and second pinion gears rotatably supported by a differential case; first and second side gears meshing with the first and second pinion gears and each coupled to corresponding one of a pair of output shafts; and a center washer, a first end washer and a second end washer each having a sliding surface that slides with an axial end face of at least one side gear of the first or second side gears, the sliding surface being lubricated by a lubricating oil; wherein a surface treatment for enhancing a solid lubricating property is performed on the washers.

Vehicle differential gear

In a clutch plate of an annular shape and a wet type, a plurality of lubrication grooves each taking a U-shape in cross-section are formed on a friction engaging surface on at least one end side. The groove is provided with a groove forming portion crossing the circumferential direction and blunt portions extending along both sides of the groove forming portion and connecting the friction engaging surface with the groove forming portion. Where a straight line passing across one side end of the groove and extending in a radial direction is assumed as a virtual straight line, in a section of the groove taken along a plane that is orthogonal to the virtual straight line and that includes the one side end, the width of the blunt portion on one side is in a range of 0.12 to 0.35 mm, and the depth of the blunt portion is in a range of 25 to 50 &#x3bc;m.

Clutch plate

A clutch plate arranged to face a contact object so as to be relatively rotatable and relatively movable includes a contact surface being able to contact the contact object via lubricant and a minute groove open at the contact surface and formed of a plurality of groove portions having a predetermined groove pitch. A ratio of a contact area of the contact surface to an area obtained by adding an opening area of the minute groove to the contact area of the contact surface is 90% to 96% in an initial state.

Friction clutch plate, friction clutch and driving force transmission apparatus

An annular wet clutch plate has lubrication grooves formed of multiple grooves in at least one of both axial end faces, the at least one of the both end faces having the lubrication grooves and a frictional engagement surface. The frictional engagement surface has a plurality of small grooves having a width and a depth that are smaller than those of the lubrication grooves. At least one of the small grooves is extended in a direction that crosses a circumferential direction of the annular clutch plate. A mean value of surface roughness of the frictional engagement surface having the small grooves is from 3.0 &#x3bc;m to 4.0 &#x3bc;m when the surface roughness is measured with the use of Rz at three positions that are offset from each other by 120&#xb0; in the circumferential direction around a central axis of the annular clutch plate.

Growing community of inventors

Tokorozawa, Japan

Takuya Tsuda