(57) An electromechanical intermittent operation device, particularly for photographic
cutters, characterised by comprising:
- a direct current motor (17), the shaft (16) of which is directly coupled to a cam
(15) for controlling the member (6) which is to be intermittently operated,
- a member (6) to be intermittently operated, provided with elastic means (11) which,
in the absence of other external forces, maintain it in its waiting condition,
- means (22) for cyclically feeding the electric motor with an overcurrent for a time
sufficient to cause it to pass beyond the half way stage in the operating cycle, and
then interrupting the electrical feed,
- means (22) for short-circuiting the rotor winding on interruption of the electrical
feed, and
- means (22) for feeding the rotor winding with a countercurrent pulse of such a duration
as to halt the motor (17) without oscillation exactly in its waiting position.
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