Punching apparatus for stamping and method for producing the same

• US 6,408,728 B1
• Filed: 09/22/1999
• Issued: 06/25/2002
• Est. Priority Date: 09/25/1998
• Status: Expired due to Fees

• Current Assignee: NGK Insulators Limited
• Original Assignee: NGK Insulators Limited
• Inventors: Kabe, Shusaku, Matsubayashi, Satoshi, Tsuji, Hiroyuki, Kitamura, Kazumasa, Noritake, Motoo
• Primary Examiner(s): Peterson, Kenneth E.
• Application Number:
  US09/401,227
• Time in Patent Office: 1,007 Days
• Field of Search: 836/19, 836/84, 836/85, 836/87, 836/91, 836/95, 836/989.1
• US Class Current: 83/687
• CPC Class Codes: B26D 7/2614 Means for mounting the cutting member
• CPC Class Codes: B26F 1/02 Perforating by punching, e.g. with relatively-reciprocating punch and bed
• CPC Class Codes: B26F 2210/08 of ceramic green sheets, printed circuit boards and the like
• CPC Class Codes: H05K 3/005 Punching of holes
• CPC Class Codes: Y10T 83/943 Multiple punchings
• CPC Class Codes: Y10T 83/9476 Tool is single element with continuous cutting edge [e.g., punch, etc.]

Abstract

A stamping punch of a punching apparatus for stamping comprises a grip member which is provided with crosspieces formed between long grooves on side walls of a rectangular parallelepiped, and a plurality of punch members which are formed integrally with the grip member. The respective punch members are arranged in parallel to one another. A plurality of long holes are defined on a punch holder. A large amount of adhesive is contained in the gap between joining surfaces when the grip members of the stamping punches are inserted and secured into the respective long holes. Accordingly, the positional accuracy of the punch member is improved, the accuracy of the hole defined through a workpiece is improved, and it is possible to eliminate any fear of occurrence of defect in shape. Further, the rigidity of the punch member can be improved, the stripper is prevented from application of unbalanced load, and the punch is easily exchangeable.

Claims

1. A punching apparatus for applying perforating machining to a workpiece by using punch members, said apparatus comprising:

a punch holder secured to an upper die, said punch holder having a plurality of longitudinal holes formed therein, wherein each of said plurality of longitudinal holes has a rectangular cross section;

a die member secured to a lower die;

a plurality of grip members detachably fastened to said punch holder, said plurality of grip members each having a rectangular cross section corresponding to that of said longitudinal holes, and a plurality of grooves formed on at least two opposing side walls of said rectangular cross section, wherein each of said grip members is fitted to said punch holder with a gap such that crosspieces formed between said grooves on said side walls of each said grip member have a circular arc-shaped configuration and slidably contact with side walls of each respective longitudinal hole, such that the position of each grip member relative to said punch holder is determined by the position of each respective longitudinal hole.

2. The punching apparatus according to claim 1, wherein said grip member and said punch members are formed in an integrated manner by using a single material.

3. A punching apparatus for applying perforating machining to a workpiece by using punch members, said apparatus comprising:

a punch holder secured to an upper die, said punch holder having a plurality of longitudinal holes formed therein, wherein each of said plurality of longitudinal holes has a rectangular cross section;

a die member secured to a lower die;

a plurality of grip members detachably fastened to said punch holder, said plurality of grip members each having a rectangular cross section corresponding to that of said longitudinal holes, and a plurality of grooves formed on at least two opposing side walls of said rectangular cross section, wherein each of said grip members is fitted to said punch holder with a gap such that crosspieces formed between said grooves on said side walls of each said grip member have a circular arc-shaped configuration with a flat top and slidably contact with side walls of each respective longitudinal hole, such that the position of each grip member relative to said punch holder is determined by the position of each respective longitudinal hole.

4. The punching apparatus according to claim 3, wherein said grip member and said punch members are formed in an integrated manner by using a single material.