Abstract: A shield tubbing for longwalls comprises a support tub and a break shield is pivotally mounted on said support tub. A double arm balance beam is pivotally supported on said tub and it includes a first arm portion which is connected at one end to a hydraulic ram. The hydraulic ram is connected to act against the break shield. The second arm of the balance beam bears on the shield between the pivotal support of the shield and the point of connection of the ram to the shield.

Abstract: A roof-support shield structure for use in an excavation to support and shield a roof above a floor of an excavation, such as a coal mine, comprises a sill beam adapted to be supported on the floor, and an inclined shield having one end pivoted to the sill beam and an opposite end pivoted to a roof cap lever. The roof cap lever includes an elongated roof cap arm which is adapted to be positioned against the roof and a crank arm which is connected to a fluid motor such as a piston and cylinder combination to pivot it and the associated roof cap arm for the purposes of positioning the roof cap arm in association with the roof. The roof is also supported by a prop in the form of a fluid piston and cylinder combination connected between the roof cap and the supporting sill. The sill is advantageously provided with a walking and aligning mechanism for coupling it to an adjacent shield which may be shifted along the mine floor therewith.

Abstract: A sea drilling jig comprises a tool carrier ship having a hull with a drill tower mounted on the hull over a hull opening which extends downwardly into the sea below the tower. A riser head is engageble in the hull opening and it may be coupled to the hull. The riser head includes a float portion with a ballast tank and it has a vertically extending riser tube opening therethrough for accommodating a riser tube and for holding it in position relative to the tower. The riser head is detachable from the carrier ship and may be ballasted to float at a level below the ship out of the turbulence area of foul weather whenever foul weather occurs.

Abstract: A rail vehicle arrangement in which a load supporting bridge boom has a pair of trucks in spaced relation therebeneath and springs supporting the booms on the trucks. The trucks have no bogie pin connection with the bridge boom and the transmission of pulling and braking loads are transmitted between the bridge boom and the trucks by steering bars in the central plane of the bridge boom swivelly connected at one end to the bridge boom and swivelly connected at the other end to a respective truck.

Abstract: An apparatus for preparing multiphase gypsum and particularly wall plaster which has an exactly defined composition comprises a plurality of heating stages including at least one high temperature stage and at least two first and second separate low temperature stages. Heating gases are directed from a combustion chamber first to the high temperature stage and subsequently into each of the lower temperature stages. One of the low temperature stages is employed as a pre-burner and it is fed with materials from a common storage bin to pre-burn the material and then direct it to the high temperature stage. The other stage is provided with the heating gases from the high temperature stage and in addition it is controlled as to temperature, humidity and quantity of heating gases in its products together with the high temperature stage products after treatment are delivered to a common cooling device.

Abstract: A hydraulic swivel drive with two adjusting cylinder-piston systems the connecting rods of which are pivotally connected to a pivotally mounted member to be actuated by the hydraulic swivel drive. The cylinder-piston units are mounted on a base member, e.g. a base plate, which base member is provided with a servo-valve controlling the supply of actuating fluid to the cylinder-piston units which are arranged in V-formation and are hooked up with the pivotally mounted member so as to be symmetrically arranged with regard to the pivot axis of the pivotally mounted member. The cylinder-piston units are directly connected to the base member and their connecting rods are pivotable relative to the axis of their pertaining cylinder.

Abstract: An ammunition magazine with a feeding device in the form of two pivotal arms for a weapon which is laterally adjustable and adjustable as to height. The magazine comprises two sections symmetrically connected to the weapon from which the feeding device grasps ammunition and moves the same to a charging position in which the ammunition is aligned with the bore of the barrel. Each of the two magazine sections has associated therewith one of the two pivotal arms which by power-operable means are so actuated that while either one moves ammunition from one ammunition magazine section into alignment with the barrel, the respective other pivotal arm moves to the respective pertaining magazine section for picking up ammunition.

Abstract: A roof support structure for excavations comprises a supporting sill beam which is adapted to be anchored in a position below the roof in the shaft or excavation being worked. The sill beam includes a front curved working face forming a closed cover plate and a movable front structure is pivoted on the sill beam at the center of curvature of the cover plate and it has a closed front end plate which is telescopic over the cover plate during pivotal movement. A cave-in shield is pivotaly connected to the outer end of the front structure adjacent the front plate and its opposite end is directed toward the roof and a roof cap structure is pivotally mounted on this end and is positioned against the roof by adjustable hydraulic props which engage against the cave in shield and pivot it to a desired position.

Abstract: A device for sealing a roof of an excavation, such as a mine shaft, including a wide surface support member or cave-in shield, which is adapted to be supported in the excavation at an angle to the roof. An open top wide surface roof cap structure is pivoted to the upper end of the support member and it comprises a plurality of nested substantially U-shape members having widely spaced apart legs which are pivoted to the upper end of the support member and which extend downwardly in the form of a shutter or bellows to the support member. The widest one of the U-shape members is formed as an extension of the horizontal portion and the intermediate ones are disposed at separate respective angles closing the space between the cap and the support member.

Abstract: A fluidized bed furnace, particularly for burning partly dehydrated sludge, comprises a furnace housing which has a bottom for supporting a fluidized bed and it includes a plurality of nozzles directed to discharge upwardly through the bottom wall into the bed for supplying heating gases including combustion air. The furnace has side walls which extend upwardly from the bottom above the bed and define a combustion chamber above the bed. The combustion chamber is closed at its top by a substantially horizontal furnace roof. At least one sludge charging opening is provided in the furnace roof for charging the sludge downwardly into the combustion chamber. A post combustion chamber is connected downwardly through the roof to the combustion chamber and it is made of a cross-section which is substantially smaller than the combustion chamber. Means are provided for supplying secondary combustion air to the post combustion chamber.