| 摘要 |
A control circuit (10) is provided for an electric motor brake (12) having an electromagnetic brake coil (14) energizable to actuate the brake to a released c ondition permitting rotation of an electric motor (16), and de-energizable to enable actu ation of the brake setting the brake to a braking condition stopping rotation of the motor. T he control circuit includes a switch (102) having an on state energizing the brake coil, an d an off state de-energizing the brake coil. A discriminating trigger circuit (76 et al) respon ds to voltage across the motor to trigger the switch between its on and off states, and discri minates between increasing and decreasing motor voltage during energization and de-energ ization, respectively, of the motor, to trigger the switch to its on state at a first mot or voltage, and to trigger the switch to its off state at a second motor voltage higher than the fi rst motor voltage, to compensate for voltage generated by continuing inertia-rotation of t he motor following de-energization thereof otherwise delaying actuation of the brake. The triggering of the switch to its off state at the second motor voltage enables faster applic ation of the brake and stopping of the motor. The same switch both energizes and de-energizes the brake coil, without a separate relay for de-energizing the brake coil.
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