GB1337811A - Rotating electrical machine and switch therefor - Google Patents

Abstract

1337811 Brush moving arrangements for electric motors DUTTON-LAINSON CO 23 July 1971 [18 Nov 1970] 34716/71 Heading H2A [Also in Division H1] In a D.C. motor with a radial-face commutator 18, the brushes 47 can be rotated relative to the stator from a central position, in which an insulating disc 26 prevents contact between the brushes and the commutator and the motor is therefore inoperative, to either a first operative position, in which the contacts pass through apertures 32-35 in the disc to cause clockwise rotation of the motor, or a second operative position, in which each contact passes through a different aperture to cause anticlockwise rotation of the motor. The brushes 47 are supported in a holder 40 which is disposed within a stationary shell 54 but which is fixed to a ring 62 and an insulating handle 103 such that the brush holder, ring and handle can all rotate together relative to the stator. A spring co-operating with projections 80, 82 normally biases the brush holder 40 to its central angular position in which the disc 26 holds the brushes off the commutator. By turning the handle 103, however, the brush holder can be rotated in one direction or the other so as to allow the brushes to engage the commutator through the apertures 32-35. Connection is made to the brushes via leads 105, 108 extending through the handle to sockets 98, 99, which in turn are engaged by prongs 96 on the ends of the conductive bolts 64, 66 which hold the brush holder 40, ring 62 and handle 103 together, the brush leads being connected to the other ends of these bolts.