| 摘要 |
1,235,127. Electro-phoretic deposition. STOLLACK A.G. Sept.6, 1968 [Sept. 8, 1967], No.42641/68. Heading C7B. In a method for electro-phoretically coating an inside surface of a hollow body 52, the electrical resistance between the bath liquid inside the body and the bath liquid outside the body is electrically shunted by means of an auxiliary bi-polar electrode having an inner part 56 in the bath liquid inside the body and an outer part 54 in the bath liquid outside the body, the auxiliary electrode being electrically insulated from the body (at 55) and not being in direct contact with a current source, and the outer part being large in comparison with the inner part. The bi-polar electrode may be formed of copper wire 56 with a mesh of iron wire 54 forming the outer part thereof; or may comprise a tube of plastics material filled with wire wool, the choice of end of the electrode to be protruded into the cavity being reversed on each occasion of use so that material deposited on an outer end, is subsequently removed when it forms the inner end of the electrode. A. C., D.C., or pulsating current may be used; for instance when using A.C. current, the counter-electrode may be formed by an aluminium bath container having an inner coating of aluminium oxide which acts as a rectifier. In the form shin in Fig. 9, motor-car body 93 is provided with an auxiliary electrode having an inner end 98 which is connected via insulated leads 96, 97 and conductor 90 to the motor-car body 95 which thus forms the outer part of the bi-polar electrode; car body 95 only subsequently being connected to the current source. |
