公开(公告)号：JP2000317570A

公开(公告)日：2000-11-21

申请号：JP12550799

申请日：1999-05-06

Applicant: SAMTEC KK

Inventor： MURAKAMI KYOJI ,  NOBO TOKUHO

IPC: B21K1/30 ,  B21J5/02

Abstract: PROBLEM TO BE SOLVED: To easily and inexpensively increase the surface roughness of the peripheral surface of a gear through window by forming the through window which is penetrating between a boss and a rim by hot forging or warm forging and formed smaller than the regular finish dimension to the regular finish dimension by old coining. SOLUTION: A steel bar is cut, heated to the temperature suitable for the hot forging, pressed for swaging, and formed in the shape of a gear, in particular a transmission gear, to obtain a stock similar in contour in which no through window is formed. The stock is bottom-punched in the hot forging process, a through window smaller than the regular finish dimension is formed in the window-punching process, the through window is expanded through the cold coining in the cold forging process after the annealing process, etc., to form a through window of the regular finish dimension. The through window smaller than the regular finish dimension may be formed in the warm forging process according to applications or materials.

公开(公告)号：JP2003094139A

公开(公告)日：2003-04-02

申请号：JP2001284852

申请日：2001-09-19

Applicant: SAMTEC KK

Inventor： NISHIDA KOKICHI ,  NOBO TOKUHO

IPC: F16C33/64 ,  B21J5/02 ,  B21J5/06 ,  B21J13/02 ,  B21K1/04

Abstract: PROBLEM TO BE SOLVED: To provide a forged bearing lace having neither uneven thickness nor decarburized layer. SOLUTION: A flat preformed body A3 after being upset is mounted on a flat forming recess 21 so as to have face-to-face contact with the bottom surface of the forming recess 21. Then, a punch 23 is lowered and moved into the flat forming recess 21, while the peripheral surface of a reference-end side 23d is in sliding contact with the side face of the flat forming recess 21, except an annular protrusion 23a at the tip of the punch 23. Then, the flat preformed body A3 is plastically deformed by the annular protrusion 23a and a circular protrusion 23c at its inner diameter side. The part thus deformed is fed into the first annular recess 23b at the tip of the punch 23 and the second annular recess 23e at its outer diameter side. Consequently, an integrally formed body is forged so that outer and inner laces are integrated. Thereafter, the inner part of the inner lace is blanked from the formed body in which the inner and outer laces are integrated. Finally, the integrally formed body is divided into the outer and inner laces.