Nsk Corporation

Nsk Steering Systems Co., Ltd.

Sumitomo Metal Industries, Inc.

Sumitomo Pipe & Tube Co., Ltd.

Gunma Seiko Co., Ltd.

Nippon Steel & Sumitomo Metal Corporation

Yasushi Watanabe

Kiyoshi Okubo

Akira Tsubouchi

Seiichi Moriyama

Atsushi Tomizawa

Shinji Okada

Masaki Tomaru

Shoichi Abe

Mitsutoshi Uchida

Koji Inoue

Yuichiro Fukunaga

Koichi Yokoi

Shiyouichi Abe

Takanori Ooshima

Kiyoshi Ookubo

Junichi Okada

Koji Marumo

Hideki Hidaka

Naoki Hara

Kazumi Shimoii

Hideki Hidaki

To form a through hole at one portion of a side wall, of an expanded portion made by plastically deforming one part of a metal tube radially outward, in a portion where the plate thickness gradually changes, a slide tool is withdrawn from inside a punch hole while applying hydraulic pressure to the inside of the side wall. At the instant of commencing withdrawal of the slide tool, the degree of progress in the shearing for the portions of the side wall matching with the two side edges of the punch hole is made different. Then, the timing for moving from shearing to rupture is made to coincide, so that of the side wall, the portions matching with the punch hole, are made reliably into a blank, and are extracted from the side wall.

Manufacturing method for metal member with through hole

A method of manufacturing a toothed power transmission member having an oil reservoir according to the present invention includes steps of forming primitive concave portion, which form a basis for the oil reservoir, on a surface of a toothed power transmission member work, and forming a tooth surface by processing the toothed power transmission member work such that a trace of the primitive concave portion is left on the toothed power transmission member thereby to form a toothed power transmission member. The trace of the primitive concave portion, which is formed in the step of forming a tooth surface and left on the toothed power transmission member, serves as the oil reservoir.

Manufacturing method for toothed power transmission member having oil reservoir and toothed power transmission member manufactured by this manufacturing method

When an outer circumference of a clamping portionand an outer circumference of a circular outer circumferenceare restrained by a diewhile inserting a non-circular punchinto a circular hole, paddingsare pressed by a semi-circular inner circumference of the dieto thereby be forced into interior of the circular hole. The volume of the paddingsis set to be substantially the same as a volume obtained by subtracting the volume of a non-circular holein an extension shaftfrom the volume of the circular hole. The circular holeis deformed, and the paddingsforced into the circular holeabut with inclined planesof the punch, whereby the non-circular holeis formed in the extension shaft

Method for manufacturing a fastening portion for a steering apparatus

In relation to a rocker arm obtained by applying cold forging to a blank made from a metal wire rod, cold forging is applied to a blank obtained by cutting a metal wire rod to a predetermined length to make a second intermediate blankhaving a pair of side wall sectionsand a basewhich connects the two side wallsat one of their respective widthwise edges. Punching is applied to the baseof this second intermediate blankto form a first and a second connection sections. In the case where it is assumed that a rolleris arranged at a position corresponding to an arrangement position of the rollerof the rocker arm to be obtained, on the inside of the second intermediate blankwhich is to be subjected to punch processing, the rollerand the basedo not interfere with each other. As a result, performance improvement of an engine fitted with this rocker arm is obtained.

Rocker arm and method of manufacturing the rocker arm

A hollow rack shaft is manufactured through a first step, a second step and a third step. At the first step, the plate-like workpiece of substantial rectangular shape is press formed into a gutter-like shape. The first die set used at this step is provided with slant die surfaces for canceling elastic recovering generated at the workpiece when the workpiece is removed from the first die set. At the second step, a row of rack teeth is press-formed on the flat bottom portion of the workpiece formed in the first step. The die set used at the second step is provided with a recess for releasing surplus workpiece material within the die clearance at a stroke end of the pressworking. At the third step, each of a pair of legs of the workpiece is bent in a semi-circular shape so as to be butted to each other. At this time, a mandrel is inserted between the legs of the workpiece.

Method for manufacturing a hollow rack shaft

A hollow rack shaft is manufactured through a first step, a second step and a third step. At the first step, the plate-like workpiece of substantial rectangular shape is press-formed into a gutter-like shape. At the second step, a row of rack teeth is press-formed by a preliminary forming step and a main forming step on the flat bottom portion of the workpiece formed in the first step. The die set used at the second step is provided with a recess for releasing surplus workpiece material within the die clearance at a stroke end of the pressworking and each die set is divided into a plurality of segments at the recess. At the third step, each of a pair of legs of the workpiece is bent in a semi-circular shape so as to be butted to each other.

Methods are provided for forming a hollow rack shaft from a workpiece comprising a rectangular plate. The workpiece is first bent into a gutter-like shape using a first die set. Rack teeth are then press-formed in a portion of the gutter-like shape using a second die set. The legs, or sides, of the workpiece are then bent around a mandrel into a semi-circular shape so as to butt against each other. Preferably, the die sets and mandrel may be adapted to improve the resulting hollow rack shaft.

The object of the invention is to provide a rack shaft having two rack teeth groups and hollowed throughout the whole body, to lightweightize the shaft and to reduce the cost. The two rack teeth groups are located longitudinally apart from each other and have phase difference related to an angle around the axis of the shaft. After the two rack teeth groups are formed simultaneously or sequentially by die forming on the flat bottoms of the workpiece beforehand gutter-shaped, the legs of the gutter-shaped workpiece are bent to butt to each other and, thereby, a tubular body of the shaft is given to the workpiece. The centers of the material are offset beforehand corresponding to the phase difference.

Hollow rack shaft and manufacturing method thereof

A workpiece for a hollow rack shaft is a substantially rectangular plate. The opposite two sides of this workpiece are respectively provided with a complementary profile composed of the continuation of a convex portion and a concave portion and when the workpiece is cylindrically formed, the profiles are mutually engaged. As the width of a part the width of which is the largest in the convex portion is larger than that of a part the width of which is the smallest in the concave portion, the two sides are prevented from being detached after engagement. Further, the opposite convex portion and concave portion are mutually caulked and hereby, mutual gap is removed.

Method of manufacturing hollow rack shaft

A hollow rack shaft is produced by forming a plate work piece and has continuous metal flow along the contour of rack teeth surface without being cut. A series of wave-like concave-convex sections is formed on the inner surface of the shaft. Thickness of tooth body and tooth bottom of the rack teeth is adjusted by dimensions of the unevenness. Thereby, stress concentration at each point of the rack shaft is prevented and the shaft is strengthened and its weight reduced.

Hollow rack shaft

In a method of manufacturing a hollow rack shaft, an approximately rectangular plate having a wide rack tooth portion, is bent lengthwise into a gutter-like cross section to provide: at the central portion, a flat bottom portion on which rack teeth are formed later and a pair of mutually facing leg portions, and, in the vicinity of both ends, a semicircular bottom portion and a pair of mutually facing leg portions. The mutually facing leg portions at the central portion have a larger clearance than the clearance of the mutually facing leg portions in the vicinity of both ends. The rack teeth are then formed on the flat bottom portion through the plastic flow of the flat bottom portion and a part of material of the pair of leg portions of this flat bottom portion. The gutter-shaped plate, on which the rack teeth have been formed, is then formed into a tube having a hollow inner surface, by bending the plate and butt joining the edge portions.

Hollow rack shaft and method of manufacturing the same

A shock absorbing type steering column assembly which is incorporated in the steering apparatus of an automobile, comprises one end portion of an outer column member formed with a female serration at one end thereof and one end portion of an inner column member formed with a male serration at one end thereof being in engagement with each other, one end portion of the outer column member being in pressure-fitting relationship to a center-side portion in the axial direction of the inner column member to form a first fitted portion, while one end portion of the inner column member is in pressure-fitting relationship to a center-side portion in the axial direction of the outer column member to form a second fitted portion, and pressure fitting strength at the first fitted portion being substantially equal to that at the second fitted portion.

Shock absorbing type steering column assembly

A production process of a yoke a for universal joint using a flat metal sheet to make a yoke for universal joint comprising a base for engaging with an end of a rotary shaft and fixing the end, a pair of arms having respective surfaces opposite to each other and extending in the axial direction of the base from opposite positions in the diameter direction and on one axial edge of the base, and press-worked circular holes coaxial with each other, formed in associated tip portions of said respective arms, wherein in portions of said flat metal sheet to become said respective circular holes, prepared holes having an inner diameter sufficiently smaller than an inner diameter of the circular holes are punched by press working, thereafter the flat metal sheet is curved to form said base and the pair of arms, then rough machining is carried out to punch the portions of the prepared holes in a nearly circular shape by press working, and thereafter press working is carried out to shave an inner peripheral edge of each hole by a small shaving amount, thereby forming the press-worked circular holes.

Growing community of inventors

Maebahshi, Japan

Yasushi Watanabe