Abstract: An apparatus for positioning devices, especially longitudinal rotary cutting blades for slitting a web of material has slides displaceable along respective guides and a belt which has oppositely moving stretches as the belt is moved in a single sense. A coupling, e.g. a double-acting piston, between the belt stretches and the slide can be actuated to press against one or the other stretch or pass of the belt to couple it with the slide. The coupling also has a cylinder-and-piston for clamping the slide against its guide to lock the slide in position when the proper position is reached.

Abstract: An apparatus for positioning devices, especially longitudinal rotary cutting blades for slitting a web of material has slides displaceable along respective guides and a belt which has oppositely moving stretches as the belt is moved in a single sense. A coupling, e.g. a double-acting piston, between the belt stretches and the slide can be actuated to press against one or the other stretch or pass of the belt to couple it with the slide. The coupling also has a cylinder-and-piston for clamping the slide against the guide to lock the slide in position when the proper position is reached.