Abstract: A coupling device for connection between the operating arm of an excavator and an implement (e.g. bucket) has upper and lower supports and a tilting device having a hinge with a tilt central axis and a transmission gear mounted to the upper and lower supports for tilting of the implement and the lower support part. The gear is a worm gear which has a segment of a worm wheel which is rigidly connected to the upper support and has its center coinciding with the tilt central axis, and a worm screw rotatably journalled to the lower support and rotated by a reversible hydraulic motor to effect tilting about the tilt central axis.