Thomson Licensing

Thomson Licensing S.a.

Michel Perrot

Philippe Berthaud

Jean-Pierre Collin

In a video recorder with a rotary head drum, a lower drum () and drum base () are joined together by laser welding to simplify assembly and reduce manufacturing cost.

Laser welded head drum for VCR

According to a first aspect the present invention is related to a head drum arrangement allowing a much easier mounting of the rotary transformer. The head drum arrangement comprises a non-rotating lower drum and a rotating upper drum, which are connected by a shaft fixed in the lower drum. The upper drum is mounted on the shaft by a bearing and preferably by two ball bearings. A rotary transformer is arranged between the lower drum and the upper drum having a fixed stator and a rotor rotating jointly with the upper drum. The rotor is non-positively held in its position by the magnetic force of a permanent magnet accommodated in the upper drum.

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Collan, France

Michel Perrot