Nippon Piston Ring Co., Ltd.

Genkichi Umeha

Osamu Hirakawa

Shigeru Urano

Shunsuke Takeguchi

Shunsuke Takegushi

Takeshi Hiraoka

Yoshiaki Fujita

Takeji Tsuchiya

Atsushi Shimura

Takasi Uda

Satoru Kato

Composite camshaft and method of making the same

Shaft member

A hollow cam shaft of the type wherein lubricating oil is distributed to the cam portions includes a rod member positioned inside the shaft pipe member and spaced from the inner pipe surface by shaft end members and guide strips to form a reduced, annular volume to be filled with oil during engine start-up. The method of making the hollow cam shaft includes forming the rod member from a resinous material by injection molding, using a removable mold positioned in the pipe through-hole, and, in a preferred embodiment, flowing the resin through the mold cavity and into a recess located in the distal shaft end member, which recess has an enlarged portion for capturing the hardened resin rod end and facilitating mold removal.

Method of making a cam shaft

Cam shaft and method of manufacture

Camshaft with lubricating oil supplying function

The method of manufacturing a lightweight, low cost hollow cam shaft includes the steps of forming an integral journal portion in a hollow pipe member by inwardly deforming a portion of the pipe member, such as by coining or spinning, the outer surface of the deformed portion being the bearing surface. Annular grooves formed immediately adjacent the inwardly deformed portion allow residue from an optional finish-grinding operation to escape. Cam members having fitting holes are fixedly mounted on undeformed pipe portions, or on outwardly deformed pipe portions.

Method of manufacturing a hollow cam shaft

A composite camshaft having a plurality of ferrous fitting members, such as cam lobes and journals, firmly bonded to a steel shaft by sintering in the presence of a liquid phase. The fitting members are fabricated as a green compact from metal powders and pre-sintered to axially shrink the compact by one-half a preselected allowance of shrinkage. Thereafter the pre-sintered fitting members are fitted on the shaft and sintered to axially shrink the compact by the remaining allowance of shrinkage and metallurgically join the shaft.

Method for manufacturing camshaft

A composite camshaft having a plurality of fitting members, such as cam lobes and journals, fabricated from metal powders having a composition of an Fe-C-Cu system which contains 17-35% by weight of Cu and joined to a steel shaft by a binding effect of Cu, which melts out of the fitting member and full penetrate a clearance between the fitting member and the steel shaft to join them as one body.

A floating seal provided at its seal face with a hardened portion, in which the body of the floating seal is made of steel, and in which the sealing member is provided at its seal face with a deposit-alloyed surface obtained by surface remelting.

Steel floating seal with remelted deposit-alloyed wear surfaces

In an oil scraper ring in which an expander is arranged on the inner peripheral surface of an oil scraper ring proper, the oil scraper ring is manufactured to present the configuration of a perfect circle in its unstressed state with a free engaging gap cut into the ring.

Growing community of inventors

Tokyo, Japan

Genkichi Umeha