Patent ID: 8864966

Claim:
Coating mask ( 1 ) for electrolytic coating of a circumferential region ( 39 ) on a mantle surface ( 48 ) of a cylindrical body ( 38 ) composed of metal, having an inner opening ( 2 ) whose diameter is at least approximately the same as the diameter of the cylindrical body ( 38 ), having two sealing lips ( 44 , 45 ) composed of elastically resilient material, disposed in the inner opening ( 2 ), that run around the circumference and delimit a coating groove ( 37 ) on both sides, which lips can be brought into contact with the cylindrical body ( 38 ) on both sides of the circumferential region ( 39 ), and then hermetically seal off the coating groove ( 37 ) that lies against the circumferential region ( 39 ), so that an electrolyte can be passed through the coating groove ( 37 ), and having at least one electrode ( 42 , 43 ) that is in contact with the electrolyte, which electrode can be connected with the pole of the direct-voltage source, Wherein The coating mask ( 1 ) consists of an elastically resilient material and has axially placed openings ( 3 to 10 ) uniformly distributed over the circumference, into which openings mandrels ( 11 to 18 ) of a stretching device ( 19 ) can be introduced, the mandrels ( 11 to 18 ) are movably mounted to the extent that the radial diameter of the coating mask ( 1 ) and thus of the inner openings ( 2 ) can be enlarged by the stretching device ( 19 ), to such an extent that the cylindrical body ( 38 ) can be introduced into the inner opening ( 2 ), whereby the radial diameter of the coating mask ( 1 ) is selected in such a manner that after a reduction in size of the radial diameter of the coating mask ( 1 ) and thus of the inner opening ( 2 ), the elastically biased coating mask ( 1 ) presses the sealing lips ( 44 , 45 ) of the coating groove ( 37 ) against the body ( 38 ) on both sides of the circumferential region ( 39 ).