Abstract: A restrictor collar for installation in the leakage water discharge pipes of Francis and pump turbines as well as pumps, which is simple in construction, is easily adjustable in the cross section thereof, and has increased security against unintentional changes of the setting thereof. Two orifice plates or disks are coaxially disposed in the pipe at a separation point therein, and each plate has an eccentrically disposed opening therein. One of the plates is fixed in position, and the other is rotatable relative thereto and in abutting engagement thereagainst. The openings are preferably circular in shape and at least partially overlap one with the other. The rotating disk, which is pressed against the fixed disk by means of a releasable flange, has insert holes radially disposed in the periphery thereof.

Abstract: A blow molding machine wherein a shield is movable to and from an operative position in which it prevents access to the mold sections. The hydraulic motors which move the mold sections can receive pressurized fluid only when the shield is locked in the operative position by a roller. When the roller is retracted from its arresting position, a mechanical power train automatically closes valves which are installed in conduits connecting the motors with oil pumps. The valve elements of the valves are mechanically coupled to each other and to the roller, and are biased by a spring which tends to maintain the roller in the arresting position. A single-acting hydraulic cylinder is employed to move the roller from the arresting position. The shield can be moved by hand and/or by a double-acting hydraulic cylinder.