N.p.w. Technical Laboratory Co.

Shinko Electric Company, Ltd.

Kunikatsu Ban

Hitoshi Kawano

Mitsuhiro Hayashi

Yukio Yamamoto

Seam welding apparatus with edge detection

A seam welder with wire electrodes inserted between upper and lower roller electrodes to weld an overlap section of a cylinderical body formed of metal plate between the electrodes. The power supply for the welder includes a rectifying circuit for obtaining a dc voltage from an ac current source, a smoothing circuit for smoothing the dc voltage, a single converting circuit to convert the smoothed dc voltage into an alternating polarity pulse voltage, a transformer for applying this pulse voltage to the upper and lower electrodes and a capacitor connected between the primary side of the transformer and the output side of the converting circuit with a capacitance that produces resonance with the inductance of the transformer primary at the pulse voltage frequency.

Seam welder with feedback control to compensate for varying welding speed

A method of lap welding an eventual can blank of a metal sheet or the like by passing a lap joint between the upper and lower roller electrodes via upper and lower wire electrodes to be heated and simultaneously applied pressure, thereby forming continuous thermal press bond sections, wherein the width of the contact surface of the upper and lower wire electrodes is set to three times the width of the lap joint, and the thermal press bond sections are formed by thermal press bonding without fusion, the center-to-center distance between adjacent thermal press bond sections being set to be in a range of 0.8.+-.0.2 mm.

Growing community of inventors

Ise, Japan

Kunikatsu Ban