GB122675A - Improvements in Systems and Apparatus for the Electric Transmission of Power. - Google Patents

Abstract

122,675. Fraser, E. M. Dec. 31, 1917. Electro-magnetic clutches; machines with two or more armatures; commutators; coils and conductors.-Power i.s transmitted from a prime mover to the road wheels of a vehicle through a combined generator and motor with a stationary field magnet; the generator armature is rotated by the prime mover, and its current is transmitted to the motor armature which is connected to the driven part. The field structure 18 has two windings 19, 19<a>, and the generator armature secured to the shaft 27 has three windings 20, 20a, 20<b>. The motor winding 21 is secured to the shaft 26, and it may be locked to the generator armature by a clutch 30. Strips 62 of soft iron are let into the sides of the conductors of the winding 21, as shown in Fig. 5, to diminish the reluctance of the magnetic circuit, and lugs 63 are provided for the attachment of the end-connectors. The commutator for the generator armature consists of bars with staggered projections 68, 69, 70, which form three rings on which brushes rest to convey current to the three windings. When the controller is moved from the neutral position to the starting position, the battery supplies current to all the armature and field windings in series. In the third-speed position, the armature windings 20, 20<a>, 20<b> of the generator are in parallel and supply current to the motor winding 21 while the field windings 19, 19<a> are connected in parallel. In the second-speed position, the generator armature windings 20, 20<a> are in parallel with each other and in series with the winding 20<b>. In the first-speed position, all the armature and field windings are in series. In the high-speed position, the generator charges the battery and energizes the clutch to give a direct drive. During braking, the motor part 21 runs as a generator, and its terminals are connected by the resistance 81. When the controller is thrown to the reverse position, the generator windings 20, 20a, 20<b> are connected in parallel. At each movement of the controller, the field coils 19, 19<a> are short-circuited by contact-segments 90.