US 4,517,435 AGranted

Electric resistance welding apparatus

OwnerBernard Humblotinventor

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Abstract

A scissors-type electric welding apparatus is provided which has a transformer, a pair of electrodes, a pair of first arms movably mounted on the transformer, an electrically insulated articulation shaft, and a pneumatic jack. A pair of second arms are pivotably connected to the articulation shaft. The second arms support the electrodes on one end and are connected to the jack on the other end in order to move the electrodes apart to position the electrodes for welding workpieces. The electrodes are electrically connected to the first arms through the second arms. Each second arm includes a contact member mounted on the articulation shaft. Each first arm includes a free end which carries a contact shoe for interacting with a contact member. A biasing member is provided for urging the contact shoes against the contact members.

Claims8

Dependent claims

Electrical resistance welding apparatus comprising;

(a) a frame on which is mounted a transformer having a primary winding adapted to be connected to a source of alternating current;
(b) a U-shaped, single turn secondary magnetically coupled to the primary winding and having a pair of spaced arms;
(c) a pair of electrodes pivotally mounted on a common shaft carried by said frame, each electrode having a contact with a circular surface that is concentric with the axis of the shaft;
(d) a fluid operated jack;
(e) coupling means interconnecting said jack to said pair of electrodes for causing said electrodes to pivot like scissors about said shaft in response to the application of fluid to said jack;
and
(f) contact shoes electrically connected to the respective arms of said secondary and in electrical engagement with the circular surfaces of the contacts on said electrodes during their pivotal movement on said shaft.

4 more elements

Dependencies are inferred from the claim text.