| 摘要 |
<p>1. An electric motor-speed reducer unit adapted to operate with a dc supply voltage V for shifting a movable element in accordance with a repeated cycle comprising a first stage, having a first duration, in the course of which the motor-speed reducer unit delivers a first torque (C1 ) at a first speed of rotation (N1 ), and a second stage, having a second duration, in the course of which the motor-speed reducer unit delivers a second torque (C2 ) distinctly higher than the first torque (C1 ), at a second speed of rotation (N2 ) distinctly lower than the first speed (N1 ), characterised in that it comprises : a) a wound-armature electric motor (4) which, operating solely at said voltage V, would develop, in the absence of saturation phenomenon, said first torque (C1 ) at a third speed of rotation (k N1 ) distinctly higher than said first speed of rotation (N1 ), and would give out an excessive calorific power in developing with the frequency of the cycle this torque (C1 ) during said first duration and the second torque (C2 ) during said second duration ; b) a resistance (5) exterior to this motor, connected in series with its armature winding and having a significant value relative to the resistance of this winding ; and c) a speed reducer (7) lowering the speed of rotation of the output shaft of the motor (4) at said first torque (C1 ) to said first speed (N1 ).</p> |
