Abstract: A method and apparatus for operating and monitoring the opening and closing cycle of electrically operated units such as electric windows and electric slide roofs which both eliminates the danger of body parts getting caught in the window and permits a complete opening and closing of the window automatically. In accordance with the invention, the speed of the drive motor is measured, directly or indirectly, and the first obtained measured value is compared with all following measured values. More particularly, this first measured value is used to detect momentary electrical and mechanical factors which change over the entire time of operation of the window, such as self-heating of the drive motor, the voltage charge of the battery, and the state and condition of the window. The processing or comparing of the measured values is carried out by a microcomputer. The actual measuring of the speed is by means of a sensor. The changes furnished by those sensors are utilized to determine the position of the window.

Abstract: A braking control apparatus for an electric motor operated vehicle including contactors for controlling the direction of rotation of a DC electric motor to effect change-over between the forward and backward modes of running of the vehicle, and a chopper circuit whose duty cycle is varied in response to the accelerator position is disclosed to comprise forward/backward change-over detecting means for detecting a change-over from the forward mode of running to the backward mode of running or vice versa, and regenerative braking activating means for effecting regenerative braking whe the forward/backward change-over detecting means detects the occurrence of change-over from the forward to the backward mode of running or vice versa.

Abstract: A method and apparatus for controlling the rotational speed of an electronically controlled power tool in both the forward and reverse direction. When the reversing switch is placed in the reverse direction, the electronic speed control circuit automatically limits the speed of the motor to a predetermined maximum value. The speed control circuit also is adapted to sense a change in the state of the reversing switch and remove power to the motor until it coasts down to a relatively slow speed or to zero before reapplying power in the opposite direction. The speed control circuit monitors the rotational speed of the motor by means of a tachogenerator comprising a ring magnet mounted on the rearward end of the rotor shaft of the motor outboard of the commutator-end bearings and a Hall effect device mounted to the peripheral flange of a carrier which encircles the ring magnet so that the ring magnet and Hall effect device are separated by a small radially extending gap.

Abstract: A hoisting apparatus and a control circuit therefor comprising a reversible electric motor drivingly connected to a hoisting drum for hauling an object up and down. The control circuit includes first and second photosensitive elements each responsive to a light beam for initiating rotation of the electric motor in either direction and means for terminating rotation of the electric motor.