Abstract: The invention relates to a scanning electron beam device in which at least one electrostatic reflector is provided for reflection of a secondary electron beam emitted by the primary electron beam on the object. This reflector is preferably located outside the beam path of the primary electron beam, and at least one electron-optical element which effects a preliminary deflection of the secondary electron beam by a small angle with respect to the beam path of the primary electron beam is provided between the object and the reflector. Such an arrangement makes it possible with comparatively low technical expenditure to reflect the secondary electron beam by a relatively large angle with respect to the unaffected primary electron beam which travels on a straight axis.

Abstract: A personnel door for sealing a room having a source of Radio Frequency (RF) radiation. The door when swung into a closed position can be energized to be partially disposed in an opening below floor level directly beneath the door. Sealing between the door and the door frame of the room can occur around the borders of the door including the part disposed in the opening below floor level. A step up into the room or use of a ramp to gain access to the room is thereby eliminated. In the preferred embodiment, the door is retained above the opening below floor level by springs and energized to move vertically downward into the opening against the force of the springs by an air cylinder.

Abstract: A device for extending supply lines to winning machines in mining operations comprises a traction chain housing which includes a covered guide for a traction member such as an endless conveyor chain. The traction member rides in the housing and is preferably covered thereby both in respect to its upper and lower reaches. A supply line support bar is secured to the traction members at spaced locations along its length for movement therewith and has a forked support extending outwardly from the housing which has one leg portion defining a support over which the supply lines are laid and another leg portion covering the supply lines. The device may be made with an endless chain conveyor which has upper and lower reaches as well as a chain conveyor having side by side reaches and in each case the housing or a cover for the housing provides for the lateral extension of the forked portion of the supply line support bar.

Abstract: A load transporting vehicle has a plurality of independently steerable wheel sets, each of which incorporates a turntable having a downwardly extending strut and a pivotally mounted trailing arm that carries a pair of wheels. The turntable is rotatably mounted on the vehicle frame. A pair of double acting piston and cylinder assemblies are coupled to rotate the turntable via a rack and pinion. A hydraulic control valve, having a control spool actuated by a boden type cable, controls the flow of hydraulic fluid to the piston and cylinder assemblies.The linear movement of the boden cable is programmed and controlled by rotatable cams. Three or four sets of cams, each set of which controls a different mode of steering, are mounted on a rotatable shaft. Each set of cams has a single cam to a given boden cable and associated wheel set. The sets of cams are interleaved to form groups corresponding to each wheel set.