Abstract: A coupling arrangement for detachably connecting a driven unit to a drive unit, which is connected to the housing of a power source. Mounted to the housing is a frame, having any desired shape, being open toward the center, and comprising two flat pieces which are connected to one another along their outer peripheral edges. The inwardly directed portions of the pieces are spaced from one another to form a slot. A locking slide open toward the center and having no bottom side is insertable in the slot. The sides of the slide and the inwardly directed portions of the frame have grooves which are uniformly dimensioned and symmetrically distributed essentially identically to each other. In at least one not fully inserted position of the slide, its grooves are aligned with corresponding grooves of the frame pieces. A drive gear is rotatably mounted to said housing in the vicinity of the open center of the frame and is operatively connected to the power source.