公开(公告)号：US3624343A

公开(公告)日：1971-11-30

申请号：US3624343D

申请日：1970-01-26

Applicant: SMITH CORP A O

Inventor： STJERNSTROM ERIK ,  BOLLINGER JOHN G

IPC: B23K9/02 ,  B23Q35/14 ,  G06M1/26 ,  B23K9/12

CPC classification number: B23K9/02 ,  B23Q35/14 ,  G06M1/26

Abstract: A welding electrode is positioned with a specific relationship to a horizontal plane at a constant resultant velocity. An X-axis drive motor and a Z-axis drive motor are connected to drive the electrode in mutually perpendicular directions. An angle drive motor angularly orients the electrode to the horizontal plane. A Z-axis tachometer provides a velocity signal as the input signal to an absolute function value generator, the output of which is applied to a quarter-circle signal generator. The latter includes an operational amplifier having a feedback circuit with a plurality of parallel paths each including a diode and a slope controlling resistor to successively vary the slope to produce a circle function output. This provides the proper input to the Xaxis drive. A Z-axis position transducer controls the Z-axis drive and also provides a stablilizing control input to the Xaxis drive and the angle drive.