GB1071670A - Improvements in or relating to electric motor driving units - Google Patents

Abstract

1,071,670. Epicyclic gearing. SECRETARY OF THE ARMY U.S.A. Nov. 29, 1963, No. 47231/63. Heading F2D. [Also in Division H2] In an electric motor driving unit, e.g. for a vehicle, comprising an independently rotatable armature 45 and field structure 49 connected together by epicyclic gearing 56 which includes an intermediate element 55 not connected directly to either the armature or the field structure but which rotates when one of these is braked to increase the speed of the other, reversal of the element 55 when the motor operates in one direction is prevented by one-way clutch which clutches the element to a non-rotatable body 48. As shown, a second, oppositely acting, one-way clutch is provided, the two clutches comprising balls (81a, 80), Fig. 6, in oppositely cammed slots 80a, 80c of rings 60, 61 whose outer peripheral equi-spaced slots, Fig. 3, are selectively engaged by detents (79, 81), Fig. 4, oppositely slidable by a rack and pinion (64) driven by the energization or otherwise of an electromagnet winding 38 having a toothed plunger 62 biased by a spring 65. High gear operation is obtained by applying to a field structure braking surface 73 an electromagnet brake 50 carried by an axially resilient tubular support 75, whereupon the ring gear 57 is held stationary, and the pinion cage 55 rotates in the same direction as the armature and in the free direction of whichever clutch has been engaged. Half-speed operation is obtained by de-energizing the brake whereupon both the armature and field structure rotate to drive the shaft. The brake, which alternatively may be mechanical or hydraulic, may be applied wholly or partially by an operator to allow the shaft to be stationary, or may be controlled automatically to obtain a predetermined field structure speed by e.g. a governor. A fan 66 impels external cooling air from openings 72 to openings 74, and the motor, of the A.C. or D.C. series type, is supplied via collector rings 70 and brushes 71. Bearings 35c, 53 support the armature shaft, 52 the field structure, and 54 the gearing spider 69 which carries the pinions 67. In another embodiment, Fig. 1, the unit is mounted within an enlarged portion (7) of a stationary axle (9) and its armature shaft (22) is connected by gearing (25, 29, 32) to a surrounding vehicle wheel hub (5) mounted on bearings 11 and having a brake (23). In modifications, the clutch rings are engaged by either of two separate electromagnets, Fig. 9, or two further cammed rings (82, 83), Figs. 7 and 8.