PURPOSE: To separate a connector smoothly and certainly associate with opening of a plate by protrusively installing a pair of pins on the connector symmetrically about the plate width direction, and providing a hook to be engaged by the pins on the inside of the plate.

CONSTITUTION: To couple a connector, a plate 6 mounted on a QD plate 4 pushes the end of a connector case 3, and the connector is pressed to the apparatus body concerned perpendicularly. At the time of separating, the QD plate 4 begins rotating, and in the condition that pins 1 and a Z-form metal piece 2 are contacting, drawing-off of the connector is started. In drawing off, the maximum force is required at the time of starting when a static friction force works, where the direction of the force which the Z-piece 2 acts on the pins 1 becomes identical to the direction of the connector being drawn off, and the direction of the contact surfaces is set so that it is free from any loss of the force and occurrence of hitches, etc. This enables lessening of the moment applied to the connector at the time of separation.