GB861895A - Improvements in and relating to taximeters - Google Patents

Abstract

861,895. Control of motors; switching held set and freed mechanically. KIENZLE APPARATE G.m.b.H. April 15, 1959, No. 12789/59. Classes 38 (3) and 38 (5). [Also in Group XIX] In a taximeter the control-shaft is driven to the " for hire," " hired," and " stopped " positions by an electric motor under control of a manually-operated switch, the motor being dynamically-braked to rest in each position by short-circuiting the armature while the stator circuit is maintained temporarily by a delayed release relay. In one embodiment, Figs. 1, 2, where the control-shaft 34 may be stepped in one direction only, depression of a push-button 1 moves a slide 3 to the position shown in which the slide is locked by a pawl 11 pivoted thereto and cooperating with a stop 16. Contacts 23-24 are thereby closed by the slide and contact pairs 19-21, 20-22, are closed by the pawl acting through a leaf-spring 18 whereby a delayed release relay E, Fig. 2, is energized to close contacts El, E2 to energize the motor armature 33 and stator 31. As the motor-driven control shaft 34 approaches its next stop position, a lobe of a cam 36 on the control-shaft lifts the pawl 11 clear of the stop 16 so that the slide is moved to the right by its biasing-spring 10. Shortly afterwards, a further cam 35 on the controlshaft permits the leaf-spring 18 to rise and open contacts 19-21, 20-22 whereby the armature is short-circuited, but the stator coil remains energized for the release time of the relay E, thus braking the motor to rest. In another embodiment, Fig. 3 (not shown), and Fig. 4, push-buttons 50, 51 are provided for reverse and forward stepping of the controlshaft, respectively. Operation of either pushbutton energizes an associated relay A (reverse), B (forward). The operated relay A or B precludes operation of the other relay (B or A), locks itself, and energizes a common delayed release relay D. In the case of forward rotation relay D energizes the motor armature 33 and stator 31 in series directly over contacts D3. For reverse rotation the motor circuit is again completed by relay D at contacts D3 but contacts A3, A4 reverse the armature current to reverse the direction of motor rotation. Camoperated contacts 80, 81, open as the desired stop position is approached, to de-energize the operative relays whereupon the armature is short-circuited by contact B4 while the stator 31 remains energized for the release time of relay D, to effect braking of the motor to rest. Two cams operated by the control-shaft, Figs. 5-8 (not shown) are used, one for forward and one for reverse rotation control. The cam profiles are slightly offset circumferentially relative to one another, the arrangement being that the leading cam is non-operative.