Nippon Piston Ring Co., Ltd.

Saitama University

Shunsuke Takeguchi

Satoshi Kawai

Takeshi Hiraoka

Yasuo Suzuki

Shigeru Urano

Hiroki Takahashi

Genkichi Umeha

Yoshiki Ishikawa

Takasumi Kubo

Masafumi Morita

Masahito Miki

Masafumi Sakamoto

Shin Ishida

Shigeyoshi Sato

Yoshikatsu Nakamura

Osamu Hirakawa

Yoshiaki Fujita

Shun Yasuda

Hiroyuki Takamura

Masaaki Yamaji

Eiji Ogawa

Takasi Uda

Yasukichi Egami

Ken Akimoto

A titanium alloy includes 15 to 27 atomic % (at %) of tantalum (Ta) and 0 to 8 at % of tin (Sn), the balance being titanium (Ti) and unavoidable impurities, when the entire 5 amount of the titanium alloy is taken as 100 at %. Therefore, the titanium alloy provided has characteristics suitable for medical device materials, biocompatible materials, etc.

Titanium alloy

An axial gap type rotating electric machine, having a stator with first tooth parts protruding in an axial direction and formed in a concentric arc-like manner, and a rotor with magnetic poles arranged in a distributed manner in the circumferential direction, and the magnetic poles include second tooth parts that protrude in the axial direction and are formed in a concentric arc-like manner, the second tooth parts being opposedly arranged so as to respectively engage with the first tooth parts with the intermediation of the air gap. The rotor is incorporated in the rotating member so as to be movable in the axial direction and so as not to be rotatable with respect to the rotating member. The rotating electric machine further includes an urging device that makes the air gap between the rotor and the stator adjustable.

Rotating electric machine including rotor arranged with intermediation of air gap

A titanium alloy includes 15 to 27 atomic % (at %) of tantalum (Ta) and 0 to 8 at % of tin (Sn), the balance being titanium (Ti) and unavoidable impurities, when the entire amount of the titanium alloy is taken as 100 at %. Therefore, the titanium alloy provided has characteristics suitable for medical device materials, biocompatible materials, etc.

In a rotating electrical machine of axial-gap type in which a stator and a rotor are opposed to each other in arrangement and winding axis is parallel with a rotating shaft direction, the stator has an 'm' protruding in the rotating shaft direction are distributed along a circumferential direction thereof, in which the winding pole is formed of a magnetic member having a plurality of teeth in a circular-arc shape in a diameter direction, and wherein the rotor is formed of a magnetic member having a plurality of teeth in a circular-arc shape in a diameter direction, and the number of the teeth of the stator and the rotor are arranged in a manner opposite to each other through air gap so as to be engaged with each other. The stator and the rotor are opposed on both sides of the rotor and the stator.

Rotating electrical machine

The temporary compacting of the powder for use in sintering is carried out, the temporary sintering is carried out, the main compacting is carried out, the main sintering is carried out, and the thickness of the radius direction of the base part of the cam before the heat-treatment is set to 3.0 mm or more.

Method for manufacturing a cam

A hollow cam shaft is composed of a hollow shaft having an inner hollow portion and an end piece which is pressure-welded to at least one end of the hollow shaft. The end piece comprises an end member which is pressure-welded to the one end of the hollow shaft and an enclosure member extending from the end member in an axial direction thereof so as to be inserted into the inner hollow portion of the hollow shaft at a time of pressure welding to define an enclosure space in the inner hollow portion of the hollow shaft. The enclosure member comprises a sealing portion having an outer shape substantially the same as an inner shape of the hollow shaft and a connection portion connecting an end surface of the end member of the end piece and the sealing portion so as to define said enclosure space between the enclosure member and the hollow shaft into which a burr generated at the pressure welding time is enclosed.

Hollow cam shaft

A mechanical element has a shaft pressure-fitted into at least one composite engaging member. The shaft has at least one engaging region disposed thereon, and at least one swollen portion formed radially outwardly around the engaging portion. The composite engaging member comprises an engaging body made of sintered alloy and having a recess therein, and a ring-shaped steel inner piece having a hardness not greater than the swollen portion. The inner piece is secured to the inside circumference of the recess of the engaging body by a securing method. The inner piece has a shaft hole formed therein, the shaft hole having a plurality of a larger inside diameter portions and a plurality of a smaller inside diameter portions arranged circumferentially, with the smaller inside diameter arranged to be smaller than the outside diameter of the swollen portion of the shaft. The composite engaging member is then pressure-fitted onto the shaft mainly in a plastic-deforming operation, with a minor chip-removing operation, if any, between the swollen portion and the shaft hole, to form the mechanical element.

Mechanical element having a shaft pressure-fitted into an engaging

A method for producing a camshaft having a tubular steel shaft and a sintered cam piece joined to the shaft. The sintered cam piece has iron tetroxide film at its surface. The camshaft is produced by assembling a powder compact to the steel shaft to provide a camshaft assembly, sintering the assembly to provide an integral assembly, correcting bending to the assembly, annealing the assembly, grinding the cam piece and effecting vaporization treatment to the assembly at a temperature lower than the annealing temperature.

Camshaft and method for producing the same

A camshaft comprising a steel shaft and a plurality of cam pieces fitted on the shaft. The cam piece is made from a sintering alloy material and bonded to the shaft by sintering. The shaft has pin-receiving holes perpendicular to the axis of the shift. The cam piece is formed on its side surface with a pin-receiving groove. A positioning pin has a lower portion tightly fitted in the hole of the shaft and an upper portion fitted in the groove to position the cam piece with respect to the shaft during sintering.

Camshaft

A camshaft having a tubular steel shaft and a sintered cam piece joined to the shaft. The sintered cam piece has iron tetroxide film at its surface. The camshaft is produced by assembling a powder compact to the steel shaft to provide a camshaft assembly, sintering the assembly to provide an integral assembly, correcting bending to the assembly, annealing the assembly, grinding the cam piece and effecting vaporization treatment to the assembly at a temperature lower than the annealing temperature.

Camshaft composition

A camshaft comprising a steel shaft and a plurality of cam pieces fitted on the shaft. The cam piece is made from a sintering alloy material and bonded to the shaft by sintering. The shaft has pin-receiving holes perpendicular to the axis of the shaft. The cam piece is formed on its side surface with a pin-receiving groove. A positioning pin has a lower portion tightly fitted in the hole of the shaft and an upper portion fitted in the groove to position the cam piece with respect to the shaft during sintering.

An assembled cam shaft including a steel cam shaft member, a journal member made of sintered material and a cam lobe. The sintered material consisting essentially of 0.5 to 4.0% by weight of carbon, 0.1 to 0.8% by weight of phosphorus, 5 to 50% by weight of copper, 1% by weight or less of manganese, 2% by weight or less of silicon, and the balance being iron and impurities.

Assembled cam shaft

A camshaft having a steel shaft and cam pieces made from a sintering iron-base alloy material and fixed to the shaft by sintering. Prior to sintering, the green or pre-sintered cam piece is fitted on the shaft and positioned by a steel positioning pin, which is inserted both into a pin-receiving hole in the shaft and into a pin-receiving groove on the side surface of the cam piece. The positioning pin contains carbon less than the steel shaft. This results in that the carbon diffusion initiates at a predetermined position where the pin and the cam piece are in contact with each other and that the cam piece always shrinks about the position.

Assembled camshaft

A method of making a camshaft of the type having a cam piece composed of outer and inner layers which comprises the steps of molding a green cam piece in a manner that the outer and inner layers are respectively made from powders of outer-layer and inner-layer forming materials, fitting the green cam piece on a steel shaft to produce a green camshaft assembly, and sintering said green camshaft assembly at a temperature in which the materials shrink and yield a liquid phase to produce a camshaft having a cam piece diffusion-bonded to the outer periphery of the shaft. The outer-layer forming material is prepared to have an axial shrinkage of 4 to 10% and shrink more than said inner-layer forming material prepared to have an axial shrinkage of 2.5 to 6%.

Method of making camshaft

A camshaft in which the outer peripheral surface of a shaft (13) is provided with an axial groove (14), and a fitting member (10) is connected to the shaft (13) by liquid-phase sintering under the state in which a projection (12) on the surface of a bore (11) in the fitting member (10) is fitted into the groove (14). The projection (12) in the bore (11) of the fitting member (10) is formed so that its cross-sectional configuration is smaller than that of the groove (14) in the shaft (13). Therefore there is no possibility that the fitting member (10) made of a green compact can be damaged during the fitting or sintering.

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Tochigi, Japan

Shunsuke Takeguchi