Abstract: A vacuum tubing valve including a first receiver tube shoulder including a tubular aperture extending along a longitudinal axis for receiving a first tubular hose. Connecting the shoulder is a stator unit including a C-shaped cavity with an opening about the side opposite the curved C-shaped wall and two apertures within the C-shaped wall and in axial alignment along the longitudinal axis. A 10 second receiver tube shoulder and tubular aperture extend along the longitudinal axis joining the stator about the second aperture. The stator includes a C-shaped rotor positioned and rotatable within the cavity, and having an elongated channel extending end-to-end. The channel is in alignment along the longitudinal axis with the first and second apertures when the rotor is in a first position, and the channel is off-set from the longitudinal axis when the rotor is in a second position.

Abstract: A chain drive arrangement is disclosed for movably driving an exposure carriage of a photocopying machine. The chain drive includes an endless chain running over two spaced apart chain gears. A carrying pin is arranged on the chain which engages into a connecting link slot transversely to the travel direction of the chain. The connecting link slot is arranged at a carrying lever of the exposure carriage. In order to accommodate movement of the exposure carriage to an intermediate or neutral position so it can be removed independently of the position in which the driving mechanism is stopped, a readily manually detachable connection is provided between the carrying pin and the carrying lever. A leaf spring hingedly connects the carrying lever to the exposure carriage and biases the lever to a connection with the carrying pin.

Abstract: A swimming pool cleaner is provided with a submergible disc-shaped transporter to which there is rotatably connected a drive jet. A flexible water supply hose provided with its own drive jet is connected to the drive jet for the transporter.