Method and apparatus for resistive welding

• US 6,204,467 B1
• Filed: 03/24/1998
• Issued: 03/20/2001
• Est. Priority Date: 03/24/1998
• Status: Expired due to Fees

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Ourednik, Frank Joseph, Greenholtz, Ben Edward Jr., Englebry, Ken George, Maatz, Donald Frederick Jr.
• Primary Examiner(s): Heinrich, Samuel M.
• Application Number:
  US09/047,081
• Time in Patent Office: 1,092 Days
• Field of Search: 219/86.25, 219/86.33, 219/86.61, 219/119, 228/106, 228/5.5
• US Class Current: 219/86.25
• CPC Class Codes: B23K 11/314 Spot welding guns, e.g. mounted on robots
• CPC Class Codes: B23K 11/315 with one electrode moving on a linear path

Abstract

A method and apparatus for resistive welding using an electrode holder having an elongated cylinder. The cylinder has a closed end and an open end. The cylinder contains a moveable piston. The piston includes a compression surface and an end adapted to retain a welding electrode. A compressible biasing member is positioned within the cylinder and is compressed between the closed end and the compression surface. An electrode is attached to the holder. The holder is preferably used as a lower electrode holder opposite a moveable upper cylinder. A work piece is placed between the upper cylinder and lower holder. The upper cylinder is extended and applies a force to the holder through the electrodes and work piece. The force causes the biasing member to compress within the lower elongated cylinder and apply a counter force against the lower surface electrode.

Claims

1. A resistance welder comprising:

a moveable cylinder having a first resistive welding electrode;

a second cylinder opposing said moveable cylinder, said second cylinder having a closed end and an open end;

a piston moveable within said cylinder, said piston having an end adapted to retain a second resistive welding electrode and a compression surface; and

an annular compressible urethane biasing member positioned within said second cylinder and compressible between said closed first end and said piston compression surface, whereby said piston compresses said biasing member when said moveable cylinder is moved to an extended position and said compressed biasing member applies a counter force to said second electrode.

2. A method of resistive welding utilizing a moveable cylinder having a first resistive welding electrode, and a second cylinder having a second electrode opposing the moveable cylinder, said second cylinder having a piston and a compressible biasing member, the method comprising:

retracting the moveable cylinder;

placing a work piece between said first and second electrodes;

extending said moveable cylinder and contacting said work piece with said first electrode and causing said work piece to contact said second electrode;

said second electrode causing said piston to compress said biasing member, said biasing member comprising an annular compressible urethane biasing member positioned within said second cylinder and compressible between a closed end and a piston compression surface; and

said biasing member applying a counter force to said second electrode whereby said second electrode and said first electrode apply equal force to both surfaces of said work piece.