Patent ID: 8895894
Filing Date: 2014-11-25
Classification: B23K

Abstract:
1. An electric spot welding gun comprising: a hollow housing; a servo motor disposed in said housing and comprising a rotor having a rotational axis; a push rod that advances and retracts according to rotation of the rotor of the servo motor; a first electrode tip that is mounted to an arm fixed to a leading end of the push rod; an encoder that detects a rotational angle of the rotor of the servo motor, the encoder disposed inside of said housing and having a rotational axis; and a set of pressing guides that are fixed by the arm integrally with the push rod and extend in parallel with the push rod, wherein a position of the first electrode tip is offset laterally relative to an axis of the push rod, wherein the rotational axis of the rotor and the rotational axis of the encoder are disposed in parallel to and offset laterally relative to each other and to an opposite side in which the first electrode tip is offset, in an offset plane in which the electrode tip is offset relative to the axis of the push rod, wherein a trailing end of the rotor on a side opposite a push rod side thereof, and an input end of the encoder are facing the same direction, and wherein the pressing guides are spaced upwardly away from the push rod in a height direction of the housing and are offset to the opposite side in which the first electrode tip is offset, and the pressing guides interpose the offset plane therebetween so as to be disposed on both sides thereof.