Patent GB-112306-A (GB)
Title: Improved Method of and Means for Automatic Electric Control of Petrol Electric and other Electric Transmission Vehicles.
Inventor: SMITH PERCY FROST
IPC: H02P9/00
Filed: 1917-01-02
Abstract: 112,306. Smith, P. F., and Robinson, V. S. Jan. 2, 1917. Controllers, actuating-mechanism for; systems for continuous-current motors only.-Automatic electric control of petrol electric and other electric transmission vehicles is effected by means of an electro-responsive device, preferably a solenoid, arranged to cut into and bring into operation resistances in the generator field, or in the generator and motor field, whereby the regulation and operation of the vehicle may be effected by controlling the speed or power of the internal-combustion or other engine. The solenoid has two windings in opposition, one, a voltage coil connected across the generator armature, as the current increases, permits the solenoid core to move outwards under the influence of a spring to cut the generator-field resistance units out of circuit and to bring it in the motor-field resistance units. The second, a current winding is connected in such manner that as the current increases the core is drawn inwards, so cutting out the motor-field resistances and bringing in the generator-field resistances. In Fig. 1 the generator armature brush 1 is connected through the winding 2 to the brush 3 of the motor armature, the brush 4 of which is connected through a revolving-switch 6, 8, 9, 10 to the motor-field winding 14. This winding is connected to the segment 19 of the controller and to one end of the coil 29 of the solenoid the other end of which is connected through the winding 15 to the brush 16 of the generator. The motor-field winding is also connected to the busbar 20 which connects together the resistance units 20<a> at one end: at the other end these units have contacts 21. The generator-field resistances 23 are connected at one end through the field winding 27 to the armature brush 1 and at the other end to the reversing-switch contact 6. The coil 28 of the solenoid is connected between the generator armature brush 1 and the contact 6. The construction of the controller is shown in Figs. 6 and 7. The apparatus is mounted in a casing of aluminium adapted to be secured to the dash board, the windings 28, 29 enclose a tube 33 of gunmetal or phosphor bronze in which works a tubular soft iron core 42 having secured at its lower end a piston of graphited carbon 39 which fits the tube 33, the lower end whereof is closed by a lid having small perforations, so that the device constitutes a dash pot. Upon the upper end of the core is adjustably secured a camplate 45 having on each side along its lower edges a series of cam surfaces 45a arranged in steps so as to come into action in succession upon a corresponding series of rollers 46. The rollers are carried by levers which turn freely on shafts 50 and carry carbon contacts 49 which engage contacts 21 connected to the resistance units 64. The camplate is guided by means of tubes 72 fixed therein and working in guides in the casing. To the lower ends of the tubes are secured the springs 30 which tend to push the camplate upwards; the upper ends of the springs are connected to adjusting nuts 66. Specification 104,819 is referred to.