METHOD AND DEVICE FOR CLUTCH OPERATION AT TIME OF SERVO STEERING

PURPOSE: To connect a parking assisting device to an automatic charging during the driving of a car without being noticed by a driver by exciting the electric coil of a clutch so as to be below the attracting torque through a direct current, and detecting a difference in revolving speeds of both the disks with an alternating magnetic flux based on thickness differences in permeable materials. CONSTITUTION: Two grooves 10' and 11' are installed side by side over each peripheral edge of both rotor and needle disks 10 and 11, and both the disks 10, 11 are made up with a permeable clutch material wherein there is no conductibility. When a switch S1 is opened, an exciting current IE flows into a clutch coil under the action of pre-resistance Rv. Value of this exciting current IE is selected so as to make a clutch be maintained in an open state during its synchronization time phase. If so, since an alternating magnetic flux is produced on the basis of each different angular velocity of both these clutch disks 10 and 11, it is made up so as to be used for the purpose of synchronization after converting it into a measuring signal for controlling a parking assisting servomotor.