US 9,463,503 B2Granted

Method of making a spanner

OwnerMing-Chang Chen, Mao-Chih Liaoinventors

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Abstract

A method of making a spanner comprises the steps of preparing a flat metal blank, forging and pressing a part of the metal blank to form a head and a shank whose width is smaller than a width of the head, pressing the head to form a first arch-shaped part, pressing a shank end of the shank to expand the shank end and then form a second arch-shaped part, and pressing the head and the shank end again to remove redundant scrap projecting from the first arch-shaped part and the second arch-shaped part and also punch finished holes in the head and the shank end respectively, thereby completing the finished spanner. Accordingly, the method reduces the waste of the material and the processing cost, decreases the use frequency of high-cost machines and promotes the processing efficiency by using the flat metal blank.

Claims9

Dependent claims

A method of making a spanner comprising:

a preparing step for preparing a flat metal blank;
an initial forging step for forging and pressing a part of said flat metal blank whereby a head is formed at one end of said flat metal blank, and a shank is forged and extended outwards from said head, said shank having a reduced width smaller than a width of said head;
a first end stamping step for pressing said head whereby said head forms a first arch-shaped part;
a second end stamping step for pressing a shank end of said shank far away from said head whereby said shank end becomes expanded by a pressing force to form a second arch-shaped part, a size of said second arch-shaped part being smaller than a size of said first arch-shaped part of said head;
and
a trimming step for pressing said head and said shank end again to remove scrap projecting from said first arch-shaped part and said second arch-shaped part and punch a first finished hole and a second finished hole in said head and said shank end respectively, thereby completing a finished spanner.

3 more elements

Dependencies are inferred from the claim text.