Movement transmission device has two levels of speed and for maintaining a force determine after the stoppage of the movement.

摘要

1. An apparatus for transmitting movement at two speed levels and maintaining a given force after the movement stops, comprising in a support structure (4) a mechanism for driving a rotary member with respect to the support structure characterised in that the drive mechanism comprises a motor (7), the control members (22) of which comprise a threshold cut-off device dependent on the resisting torque, coupled to said driven member by a first transmission path comprising a torque limiter (5, 5'), the output (5a, 5'a) of which is coupled to the driven member (1, 1') by means of a resiliently deformable connection (6, 16, 17, 41), and by a second transmission path comprising a reducing means (10), the output (10b) of which is connected to a rotating member (13, 14') provided with a first friction surface for co-operating with a second friction surface (15, 41a) which is connected for rotary movement to the driven member (1, 1'), said second friction surface being displaced between a first position in which it is remote from the first friction surface and a second position in which the two surfaces are in contact, by said deformable connecting means when the latter are deformed under the effect of a resisting torque applied to the driven member (1, 1').