| 摘要 |
980,696. Change-speed and reverse gear; change-speed control. W. HOLZER. May 17, 1961 [May 17, 1960], No. 17964/61. Heading F2D. [Also in Division H2] Change-speed or reverse gearing for washing machines, &c. comprises an electric motor having a sliding mesh pinion fast upon its armature shaft, changes in the energization of the electric motor causing the armature to slide axially, as well as varying the torque of the motor, so that the pinion slides out of mesh with one driven gear and into mesh with another gear. In one form, an electric motor 1, Fig. 1, has an armature 2 fast on the shaft of which is a pinion 3, a spring 9 biasing the armature to the position shown so that the pinion meshes a gear 4 fast on a shaft 8 driving through a gear train 12 to an output shaft 13. In the position shown, the motor 1 is fed through a circuit including a resistor 10. On shorting the resistor 10 by means of a switch 11 to increase the field of the motor 1, the armature 2 moves upwardly against the bias of the spring 9 so that the pinion 3 no longer engages the gear 4 but instead engages a gear 5 of a reversing double gear in turn meshing a gear 7 fast on the shaft 8, which, together with the shaft 13, now rotates in the opposite direction. In a modification, Fig. 2 (not shown), two pinions of different diameters fast on the shaft of the armature 2 are selectively slidden into mesh with different diameter pinions fast on the output shaft 13, depending upon the degree of energization of the electric motor 1. In another modification, the armature 2, Fig. 3, of the electric motor 1 carries a pinion 3 selectively meshed with different ratio gear trains 31 . . . 35 driving to an output shaft (not shown) depending upon the degree of energization of the motor, controlled by resistors 19 . . . 23 in series which may be short-circuited by contacts 24 . . . 28 operated, e.g., by pushbuttons. A pawl 30 co-operates with a ratchet 29 on the armature shaft to retain the latter in a selected axial position, in mesh with one or other of the associated driven gear trains, and may be released by means not described feeding a pulse of current on actuation of one or other of the contacts 24 . . . 28. Alternatively, the pinion 3 may be axially positioned by the design of the armature and co-operating field structure of the motor, e.g. by multiple tapped windings. |
