Abstract: In an anchor rod (1) for a synthetic resin adhesive anchor having a shaft (2) with a plurality of area segments (4) arranged in axial succession, the surface of which is low-friction with respect to synthetic resin mortar (6), areas (4) are formed. Viewed in a circumferential direction, the areas are arranged side by side such that a desired splitting zone (9) is created in the transition region of two adjacent areas (4) of this type.

Abstract: In an anchor rod (1) for a synthetic resin adhesive anchor having a shaft (2) with a plurality of area segments (4) arranged in axial succession, the surface of which is low-friction with respect to synthetic resin mortar (6), areas (4) are formed. Viewed in a circumferential direction, the areas are arranged side by side such that a desired splitting zone (9) is created in the transition region of two adjacent areas (4) of this type.

Abstract: A double-chain conveyor is assembled of trough sections defining a bottom plate provided with lateral guiding walls for scraper elements and intermediate guides extending along the entire length of the conveyor and guidingly engaging lateral edges of flat chain elements arranged parallel to the bottom plate of the trough. The flat chain elements are provided with oblong holes extending in the direction of the chain and linking vertically directed ring-shaped chain elements with a play which permits shifting movements of all chain elements in the longitudinal direction. Intermediate drives are provided between superposed bottom plates of the trough and drive a chain wheel engaging the flat chain elements both in the upper and in the lower flight of the conveying chain.

Abstract: A mine roof support structure includes a floor skid, a supporting shield pivotally connected thereto by a pair of rocker arms forming a lemniscate guide, a roof cap pivotally connected at a roof cap joint to the shield, and hydraulic props supporting the roof cap. A hydraulic actuator is pivotally connected at opposite ends to the skid and to one of the arms, and the other of the rocker arms is disposed nearer the coal-face end of the support than the one arm. Such other arm is longitudinally adjustable and is pivotally connected at opposite ends to the skid and to the shield. This other arm is so constructed that its opposite ends may be adjusted relative to one another to enable the cap and the roof cap joint to follow a lemniscate path during settling of the roof and to follow a circular arc during a lowering of the cap toward the skid upon actuation of the hydraulic actuator.

Abstract: A fluid-operated device for simultaneously pretensioning a plurality of bolts connecting a first body to a second body in which the bolts are screwed with threaded end portions thereof into corresponding threaded bores in the second body and project with clearance through bores in the first body and with opposite threaded end portions thereof beyond the first body.

Abstract: A coupler for use in clamping down a lid over a pressure vessel has a pair of clamping jaws movable toward and away from one another respectively between clamping and unclamping positions. The cylinder of a pressure-operated piston and cylinder unit is pivotally connected to support plates extending outwardly of one of the jaws, and the piston of such unit is pivotally connected to one end of the pair of linkages pivotally mounted at the other end thereof to the other of the clamping jaws. Curved slots defining tracks are provided in the support plates, and rollers are located on the linkages in engagement with the slots for controlling simultaneous movement of the clamping jaws toward and away from one another upon actuation of the piston and cylinder unit.

Abstract: An arrangement for threading connecting elements, particularly threading bolts equipped with nuts threaded thereon, into and out of tapped bores of a reactor vessel to attach a lid to, and detach the same from the same includes a carrier ring which is supported on the lid during the threading operations, and a bolt-rotating device which is supported on a double-rail track mounted on and extending over the entire circumference of the carrier ring with a spacing therefrom, for displacement in the circumferential direction of the track.

Abstract: An axial piston machine of the swash plate type includes a valve plate provided in a front face thereof with control openings which communicate at opposite ends through bores with the rear face of the valve plate. A plurality of shallow pockets, respectively forming hydrostatic bearings, are also provided in said front face, which communicate through connecting bores respectively with throttle bores, which in turn communicate at inner ends with respective control openings, and in which spring loaded throttle pins are arranged with small clearance for oscillating movement.