Attachment of fork fitting to fork leg

• US 4,404,458 A
• Filed: 07/01/1981
• Issued: 09/13/1983
• Est. Priority Date: 07/07/1980
• Status: Expired due to Term

• Current Assignee: Tange Industries Limited
• Original Assignee: Tange Industries Limited
• Inventors: Tange, Yasuhiro
• Primary Examiner(s): Reynolds, B. A.
• Assistant Examiner(s): Sigda, Catherine
• Application Number:
  US06/279,261
• Time in Patent Office: 804 Days
• Field of Search: 219/104, 219/105, 219/107, 219/67, 219/149, 219/150 R, 219/93, 228/173 F
• US Class Current: 219/150.00R
• CPC Class Codes: B23K 33/008 for automotive applications
• CPC Class Codes: B23P 15/00 Making specific metal objects by operations not covered by a single other subclass or a group in this subclass
• CPC Class Codes: B62K 19/20 welded, soldered, or brazed

Abstract

A method for attaching a bicycle fork fitting to a fork leg is disclosed, using a particular fork fitting means. A steel pipe is formed with a fork leg including its one closed distal end with a joint. The fitting means is provided with projections at the portions near to both ends of the side thereof to be welded. Electric currents are passed through the closed portion of the fork leg and the projections of the fitting which are brought in contact with each other under pressure. Upon reaching a temperature suitable for welding, the thus integrated arrangement is upset under greater pressure, so that the fitting is welded to the fork leg.

Claims

1. A method for attaching a bicycle fork fitting to a fork leg comprising the steps of forming a steel pipe into a fork leg, closing the distal end of the pipe with a joint by shearing, providing a fork fitting with an indentation and a pair of projections on either side thereof at the distal end of said fitting, said indentation being the same shape as the closed distal end of said pipe but slightly smaller in its transverse dimension, butting said projections against said closed distal end of said pipe, applying two pairs of welding electrodes to said pipe and said fitting, passing electric currents by means of said electrodes through the closed portion of the fork leg and the projections of the fitting while bringing the same in contact with each other under pressure, and upsetting under greater pressure the thus integrated arrangement upon reaching a temperature suitable for welding, whereby the fitting is welded to the fork leg.

2. A method as recited in claim 1, in which said closed distal end of the fork leg is in the form of a semi-circular shape.

3. A method as recited in claim 1, in which said closed distal end of the fork leg is in the form of a triangle.

4. A method as recited in claim 1, in which said distal end of the fork leg is blanked out by pressure perpendicularly to the axis thereof.