摘要 |
685,558. Variable-speed gearing. SIPER SOC. ANON. March 6, 1950 [March 29, 1949; Sept. 27, 1949] , No. 5639 / 50. Class 80 (ii). In a multiple-speed gear-box each strikerrod 1 is moved to its operative positions by separate electromagnets 3 and is locked in those positions upon energization of a latching electromagnet 11 which has an armature 12 formed with a spur 13 adapted to engage notches 14 in the striker-rod 1. As shown the striker-rod 1 is held in its middle or neutral position by compression springs 4 and has at 2 an armature portion for the electromagnets 3. Upon energization of one of the electromagnets 3 the rod 1 moves to the right or left to introduce a gear ratio and when it reaches its working position it actuates a switch 8 which acts to de-energize the magnet 3 and energize the locking electromagnet 11. A wiring diagram for a gear-box with four forward and one reverse speeds is shown in Fig. 2. A switch arm 18 engages contact 20 for the forward speeds and a contact 25 for the reverse speed. Another switch arm engages contacts 21-24 for the forward speeds. A single locking electromagnet may lock a plurality of striking rods. In a modification embodying three forward and one reverse speeds each striking-rod electromagnet 51-57, Fig. 10, is in series with the locking electromagnet 61. In the neutral gear position a switch 67 is closed to short circuit the coil 61. Upon energization of an electromagnet 51-57 a strikerrod is moved and when it reaches a working position it actuates cam means to open the switch 67 whereupon the electromagnet 61 is energized to lock the striker-rod. In this construction the current through the electromagnets 61-57 when the gears are in a working position is not zero as in the first embodiment but is considerably less than the current which flows during the gear changing operation. |