Patent GB-453377-A (GB)
Title: Improved method of and apparatus for manufacturing coated insulated wires
IPC: H01B3/10
Filed: 1935-07-05
Abstract: 453,377. Electromagnetic switches. ZAIDAN HOJIN RIKAGAKU KENKYUJO, 31, Kamifujimae-cho, Komagome, Hongo-ku, Tokio. July 5, 1935, No. 19223. Convention date, July 19, 1934. [Class 38 (v)] [See also Group VIII] Coated insulated wires are made by applying one or more layers of coating material to the wire, drying, passing the coated wire through a detecting device for spots of poor insulation, then passing it through a spot coating device which is automatically controlled by the detecting device so that the spot coating is applied at the defective spot, and finally drying the coated wire. A wire w from a reel 1 is passed through a cleaning die 2, coated by a roll 4 rotating in a bath 3 and dried in an oven 5. It then passes through a detecting device comprising a cotton band 8 kept moist by dipping in a water pot 7, around a pulley 9, through the spot coating device, and then through the drying oven 5. Alternatively the wire is passed round a pulley 31 and again coated, spot coated and dried. When a bad spot passes the detector current flows through an electric circuit A including the wire and the detector, is amplified at 32 and operates an electromagnet 24 associated with a relay 18, consisting of a rotating metallic disc 20, driven from the pulley 9 by a belt 30, and carrying a number of metallic pins 19 which are mounted to slide axially when contacted by a roller 22 at the end of an arm 23 pivoted at 21 which is attracted when the electromagnet 24 is energized. On further rotation of the disc 20 the projected pin contacts with a roller 26 and closes circuit B including an electromagnet 16 associated with the spot coating device, which comprises a pair of spring-controlled levers 15, 15<1> pivoted at 14, 14<1> and carrying at their free ends rollers 13, 13<1> which engage with a roller 12 rotating in a bath 11 of coating material. A roller 27 returns projected pins 19 to their normal retracted position. The relay 18 is adjusted so that the time taken for the wire to travel from the detector 8 to the spot coating device is equal to that taken for the pin projected by the roller 22 to contact with the roller 26. The Specification as open to inspection under Sect. 91 comprises also the modified form of apparatus shown in Fig. 4 (Cancelled) in which the wire is coated by passing downwards into a bath 3 around an immersed roll 4a and the spot-coating device comprises a cylinder 13a carried on the end of a spring- controlled lever 15 which is attracted when the electromagnet 16 is energized, thus causing a quick downward movement of the cylinder 13a, the returning movement of which is controlled by a dashpot 17a to avoid further spot coating during its return to normal position. In the alternative form shown in Fig. 6 (Cancelled) the spot coating device comprises an iron lever 15b carrying a dipper 13b normally dipping in an enamel bath 11. When the electromagnet 16 is energized the dipper is raised and transfers a small quantity of enamel to the groove in a roller 12a over which the wire runs. Means are also described for cleaning the wire prior to coating by means of cotton bands impregnated with distilled water or alcohol which pass over rotating resilient felt or rubber rollers between which the wire passes. The rollers may rotate in a direction opposed or at right angles to the direction of motion of the wire. This subjectmatter does not appear in the Specification as accepted.