GB433016A - Improvements in and relating to electric motors - Google Patents

Abstract

433,016. Motors. DESOUTTER BROS., Ltd., and DESOUTTER, C., 73, Baker Street, London. Nov. 2, 1934, No. 31451. [Class 35] [See also Group XXXVI] Terminals and accessories, arrangement on machines.-In an electrically-driven rotary tool having a readily detachable switch, the switch has one or more contacts so that when inserted in position, connection is made by spring pressure with other contacts on the motor. The switch comprises a box 17 formed of two parts of insulating material fitting in apertures 7<1> in the motor casing 7. The movable part of the switch consists of a pivoted conducting fork 29 connected by a spring 34 to a sliding button 33, and in the lower portion of the button, the fork connects with two spring contacts 25, 28, Fig. 3. The contact 25 forms part of a conducting plate 22 which has also a spring limb 23 contacting with the metal liner 21 carrying the brush 15. The insulating cover 20 of the brush-holder engages a groove in the switch box and acts as a key therefor. The other switch contact 28 is carried by a spring limb 27 which has a second spring limb 35 making connection with a contact 36 on the field winding bobbin 12. The other terminal of the field winding consists of a contact plate 37 upon which bears a spring-pressed plunger 38 carried by the switch box and connected by a lead 39 to a terminal 41. Alternatively, a further plunger on the switch box connected to the plunger 38 may connect with a contact carried by the casing. The switch may control more than one circuit. The switch casing or a part thereof may be formed in one with the outer insulated part of the brush holder. Specification 433,014 is referred to.