Abstract: A wiping arrangement for windows of power vehicles has a wiping element with a wiper shaft, rotary direction-reversible drive having a rotatable driven element, swinging drive with a driving element rotatable about a center and provided with a gripping element and a guide, and connecting the driven element of said rotary drive with the wiper shaft of said wiping element so that when the driven element rotates in one direction the wiping element covers a circular, segment-shaped wiping field and performs wiping step over a predetermined wiping field, and when the driven element rotates in a reverse direction the gripping element arranged on the driving element of the swinging drive means moves radially away from the center with the aid of the guide and thereby the wiping element is transported to a parking position lying beyond the wiping field, a structural element connected and rotating together with the gripping element during the wiping step, but uncoupled from the gripping element for the radial movement

Abstract: A vacuum switch of the type having contact electrodes which are coaxially movable with respect to each other for interrupting large currents. In one embodiment where a substantially cylindrical housing is arranged around the contacts, a radially inward bulge of metallic material is arranged near a center plane intermediate of the contacts. Such a bulge may be formed by inserting a metallic, annular insert within the housing, or producing an annular bulge in the housing itself. The bulge produces an inclination which is selected so that a plasma which flows from the arc which is produced upon interruption of the current is deflected in the axial direction. Such deflection reduces the stress on the vapor shield and is particularly advantageous with single-pulse switches which experience relatively long arcing times.

Abstract: Hydrogen cyanide in hydrogen cyanide containing gas is transformed into ammonia by a special iridium catalyst in the presence of at least the equivalent amount of hydrogen for the change. The ammonia is analyzed to provide a measure of the hydrogen cyanide in the hydrogen cyanide containing gas.

Abstract: An operator safety device includes a plurality of covers for covering parts of a machine to protect an operator against contact with these parts when the machine is in operation. At least some of the covers are movable between a closed position where the covers do not cover these parts and the latter are readily accessible and constitute a danger of accidents. A switch is operable for shutting down the machine when at least one of the covers moves from the closed into the open position. A linkage connects the covers with the switch for actuating the latter whenever at least one of the covers moves from the closed into the open position.