| 摘要 |
1292207 Making electromagnetic coils; coiling helices; electromagnetic forming RCA CORPORATION 6 Feb 1970 [12 Feb 1969] 5760/70 Headings B3A B3E and B3Q [Also in Division H1] In a method of making a wire wound electromagnetic coil, a side portion of the wound coil is electromagnetically rammed towards a bounding surface of a cavity containing the side portion by passing a current pulse through the coil while the side portion is subjected to a transverse magnetic field directed across the cavity transversely of the side portion and of the ramming direction. An electromagnetic beam deflection yoke for use with a colour television tube, for example, is wound on an arbor comprising male and female members 21, 22 supported respectively by mounting plates 23, 24. The plate 24 is mounted on a spindle 25 which passes through a hole 27 in a block 28 in the female member, the spindle being rotated to impart rotation to the members 21, 22 in the direction of the arrows. To wind a coil, one end of the wire is attached to a starting terminal 42 and the members rotated. Side deflecting rods 39, 41 and end wire deflecting vanes 49, 51 guide the wire into the winding cavity of the arbor. The rods 39, 41 extend at right angles to the vanes 49, 51. The female cavity forming member 22 includes a window block 32 on either side of which are recesses 33, 34 for accommodating the side conductors of the coil. The male cavity forming member 21 includes body sections 44, 45 which have configurations conforming to those of the neck and flared bulb sections of the cathode-ray tube with which the coil is to be used. The sections 44, 45 are separated by a window aperture 46 which matches the block 32. When winding is complete, the other end of the wire is attached to a terminal 43. The block 28 and the sections 44, 45 are of permanent magnet material or of a magnetically permeable material, e.g. cold rolled steel. The block 32, spindle 25 and plates 23, 24 are preferably of non-magnetically permeable material, e.g. brass or aluminium. When the coil has been wound, with the mated male and female members 21a, 22a, placed between magnets 55, 56, which may be permanent magnets or the poles of an electromagnet, a current is pulsed through the coil via the terminals 42, 43. Since the coil is in a magnetic field having flux lines 57, 58, the current flowing through side conductors of the coil, shown diagrammatically at 59-59a, 61-61a, causes the conductors to move in the direction of arrows 62-65 thereby providing an even compaction of the turns. Further the conductors immediately adjacent the coil window may be made to lie along lines which are concave to the window and along longer than geodesic lines, Figs. 6-8 (not shown). The wire of the coil may be coated with thermoplastic insulation so that the coatings bonde together due to the heat generated by the electrical pulse. |
