GB186496A - An improved terminal block or switch for electric motors adapted for running or alternating or continuous-current supply - Google Patents

Abstract

186,496. Fairweather, W. C., (Diehl Manufacturing Co.). Aug. 23, 1921. Motors, controlling; frames and supports; driving arrangements.-A motor is adapted for running alternatively on a continuous or alternating-current supply by means of a movable plug in a contact block mounted on the motor casing and adapted to cut out some of the field turns for alternating-current working. The insulating contact block 1, shown on the motor in plan view in Fig. 1 and in section in Fig. 3, carries terminals 3, 4 connected to the mains and two sunk sockets 7, 8 screwed to receive a single plug 10. The terminal 4 is connected to a spanning contact member 9 which extends over the sockets 7, 8 and is insulated from them by washers 11. When the plug 10 joins the spanning member to the socket 8, as shown in Fig. 3, the motor is adapted for continuous-current, the circuit being from the main 5, lead 20, armature 18, full field coil, lead 16, socket 8, plug 10, member 9, and terminal 4, to the other main 6. For alternating-current supply, the plug is transferred to the socket 7 and the circuit is made through the lead 17 so that the portion 15 of the field coil is not included. The motor is secured to the driven machine by a bracket 21 and has a jockey pullev 22 mounted on a pivoted arm 23 which is held in a belttightening position by a spring 24.