Patent GB-1315596-A (GB)
Title: Switch mechanism for controlling a drive motor of a time switch
IPC: G04C13/12
Filed: 1971-05-12
Abstract: 1315596 Master clocks FRIEDRICH ERNST BENZING KONTROLLUHRENFABRIK 12 May 1971 [22 July 1970] 14470/71 Heading G3T [Also in Division H1] A switch mechanism for controlling a motor for alternative autonomous or non-autonomous drive of a time switch which requires a high torque, the motor being operated periodically to step the time switch, comprises a drive spring whose one end is supported on a part connected to the shaft of the motor and whose other end acts on a coupling disc, and contacts for the operation of the motor are closed in dependance upon the angular position of the coupling disc and opened in dependence upon the angular position of the coupling disc and opened in dependence upon the angular position of said part connected to the motor shaft, on autonomous drive the coupling disc rotating under control of an escapement driven by the drive spring and on non- autonomous drive the coupling disc being released periodically by a relay which receives impulses from a master clock. As shown an electric motor 2 is coupled by gears 3, 4 to a shaft 1 driving a time switch (not shown), and is controlled by a micro-switch 5 actuated by a follower 24 engaging both of the cam discs 6 and 12. The disc 6 is secured to shaft 1 while disc 12 is loosely journalled thereon but coupled to disc 6 by pin 19 moving in an arcuate slot extending over 180 degrees of disc 12 Figs. 4 and 5, (not shown). A spring 7 is connected at one end to the pin 19 and at its end to a pin 20 on a coupling disc 8. The disc 6 has two diametrically opposed recesses 22, 22', Figs. 4 and 5, (not shown) which in its rest positions allow the follower 24 to enter and open switch 5. The disc 12 has two rises (23, 23') which can obturate the recesses (22, 22') to lift the follower 24 and close switch 5. Thus switch 5 is normally open. Disc 8 is coupled to a wheel 9 which, by means of a lever 17, can be moved axially to engage, alternatively, either an escapement mechanism 11 or a forked lever 14. The lever 14 normally restrains a pin 31 on wheel 9 but is moved by a relay 13 to release wheel 9 when an impulse is received from a master clock. The disc 8 is thus turned by spring 7 either slowly under control of the escapement (autonomous function) or quickly when an impulse causes lever 14 to pivot; in each case the pin 20 engages a pin 21 to rotate the disc 12 such that at the end of fixed time interval (e.g., one minute) the disc 12 has rotated 180 degrees and a cam rise (23 or 23') lifts follower 24 to close switch 5, the arcuate slot in disc 12 permitting this rotation with respect to disc 6. The motor 2 now runs and pin 19 on disc 6 quickly rewinds spring 7 until, after nearly 180 degrees of rotation, pin 19 entrains disc 12 to move the cam rise (23 or 23') away from the follower 24 which falls into a recess (22 or 22') of disc 6 and the motor stops. The cycle then repeats. Thus spindle 1 is rotated 180 degrees once every minute (for example). The disc 8 may have a cam profile to act via a follower 35 on a further switch 16 thereby providing pulses so that when in autonomous operation the device may itself function as a master clock if desired.