Method of manufacturing saddle coils having different dimensions

摘要

For the low-cost manufacture of differently dimensioned saddle coils (2) which have good long-term dimensional stability, although because of the thickness of the wire used for the saddle coil, the dimensional stability cannot be achieved with this wire alone, and which fit differently curved surfaces and have a number of turns, use is made of a prefabricated wire having a first insulating-varnish coating directly thereon and a second insulating-varnish coating applied to the first coating, the second coating having a baking temperature lower than the softening point of the first coating. The coil is wound on a coil form (1) to form a flat coil (21), the coil form being a prefabricated part of a flexible plastic which is dimensionally stable at the baking temperature. The flat coil is then fitted, together with the coil form (1) , to the curved surface of a corresponding dummy to form a still dimensionally unstable saddle coil. Then, a current whose strength is so chosen that the baking temperature is at least reached is sent through the saddle coil until the second insulating-varnish coatings are bonded, baked, or fused at least to each other. After the current has been switched off, the second insulating-varnish coating is allowed to solidify, and the now dimensionally stable saddle coil (2), together with the coil form (1), can be used for the intended purpose.