Abstract: In a frictional rotary connector having a tapered ring arrangement (3) to be placed onto a shaft and having at least one tapered ring section (e.g. 4a) with an inner surface for abutting the shaft, and with an oblique outer surface (e.g. 5a), at least one tensioning ring element (e.g. 6a) with an oblique inner surface, which element slides between a starting position and a clamping position on the oblique outer surface (e.g. 5a) of the tapered ring section (e.g. 4a), and a tensioning ring for moving the tensioning ring element (e.g. 6a) in order to lock the tensioning ring element (e.g. 6a) in the clamping position at least one retaining element (8) is provided which is arranged to be guided in a radial direction from a free position to a clamping position, wherein the retaining element (8) axially locks the tensioning ring element (e.g. 6a) in the clamping position.

Abstract: In a frictional rotary connector having a tapered ring arrangement (3) to be placed onto a shaft and comprising at least one tapered ring section (e.g. 4a) with an inner surface for abutting the shaft, and with an oblique outer surface (e.g. 5a), at least one tensioning ring element (e.g. 6a) with an oblique inner surface, which element slides between a starting position and a clamping position on the oblique outer surface (e.g. 5a) of the tapered ring section (e.g. 4a), and tensioning ring means for moving the tensioning ring element (e.g. 6a) in order to lock the tensioning ring element (e.g. 6a) in the clamping position at least one retaining element (8) is provided which is arranged to be guided in a radial direction from a free position to a clamping position, wherein the retaining element (8) axially locks the tensioning ring element (e.g. 6a) in the clamping position.

Abstract: A frictional revolving joint for joining a hub to a shaft has a tapered ring arrangement with two tapered ring sections with conical outer surfaces that have a V-shaped cross-section and a clamping ring made of two clamping ring elements that enclose the tapered ring arrangement.The ring shaped pressure chamber formed by the front surfaces of both clamping ring elements may be put under pressure by a hydraulic fluid, causing the clamping ring elements to slide outwards on the V-shaped tapered ring sections.The ring-shaped pressure chamber (57) is sealed itself by sealing rings (55a, 55b,; 63) that engage the clamping ring elements (53a, 53b) in all positions of the latter. The ring-shaped pressure chamber (57) is thus hermetically sealed and hydraulic fluid cannot escape outwards.

Abstract: Methods are provided for translating a face support comprising a plurality of support units arranged side-by-side at an initial position. In the first embodiment, a first pair of alternately positioned support units are moved a predetermined distance from the initial position. Next, a second pair of alternately positioned support units are moved the predetermined distance. One of the support units of the second pair is positioned between the first pair. These moving steps are repeated until the entire plurality of support units is moved the desired distance. In the second embodiment, the first moving step is duplicated. Then, a single support unit located between the first pair is moved the predetermined distance. These two moving steps are repeated until all of the support units are moved.

Abstract: A shield type support for use in underground mining comprises a floor construction with one or more pressure operated extensible and retractable rams mounted on the floor and connected at their upper end to a roof-member. The roof-member is articulated at one end to a breaking shield which has an opposite end which is supported by lemniscate guide rods. The lemniscate guide rods are carried on a support which is mounted for adjustable movement on a column supported on the floor. In addition, this support also advantageously carries an additional adjusting element in the form of a telescopically retractable and extensible ram connected between the support and the roof structure at a spaced location from the other rams.

Abstract: A coupling gear for connecting two side-by-side, longitudinally extending shiftable skids of a divided footwall skid of a lemniscate shield timbering frame for actuation by a fluid pressure operated piston and cylinder combination which is adapted to be connected thereto, comprises, a double crank joint which includes first and second outer crank pins extending transversely between the skids with bracket means adapted to be positioned on the respective skids for rotatably supporting the outer crank pins on the respective skids and, wherein, the crank pins have outer ends rotatably supported in the bracket means and opposite inner ends and including first and second longitudinally extending, substantially parallel crank arms, one of which has a first end connected to the inner end of the first outer crank pin and the other of which has a first end freely rotatable on the second outer crank pin and with a central crank pin having a first end freely rotatable in the first crank pin arm opposite end and an opposi

Abstract: A timbering device connected to a longwall conveyor disposed toward the mining face of an excavation for progressively timbering frames from the gobbing side toward the mining face side comprises first and second skids which are adapted to be shifted over the floor. The guide piece is pivoted to one of the skids adjacent the gobbing side thereof and it has a guide slot extending toward the mining face. A push rod has one end connected to the longwall conveyor and an opposite end having a slide portion which is slidable in the guide piece guide slot. A thrust drive piston has a gobbing side end pivotally connected to the slide piece portion of the push rods and has an opposite mounting face end which is pivotally connected to a bracket carried under one of said skids. The sliding plane control device is carried by the pusher rod.