Abstract: The present invention relates to a brake disk (9), in particular a brake disk (9) for an electromagnetic brake, which can be used as an emergency stop brake and/or as a dynamic brake. In order to ensure that when the weight is low, the actuation force between the friction partners is large because of a magnetic field which is switched on, the brake disk (9) has a support (10) made of friction material and a metal ring (11, 11?) which is disposed concentrically thereon.

Abstract: A 2-component composition is disclosed which contains an inorganic binder as well as a curing agent composed of water or an aqueous solution. The composition also contains substances which regulate solidification and curing, as well as, if necessary, conventional amounts of slag powders, fillers and blowing agents. The composition is distinguished by the fact that it cures rapidly even at low temperatures and can be used in small amounts. As a result, the composition is particularly suitable as a dowelling composition for fastening anchor rods in boreholes.

Abstract: A two-chamber cartridge for fastening anchor elements in holes of a support structure is prepared. The chambers contain cycloaliphatic compounds and the reaction initiators. The separator separating the two chambers is destroyed inside the bore hole so that the mixing of the cycloaliphatic compounds and the reaction initiators can take place.

Abstract: A composition and method are disclosed whereby the formation of geopolymers from curable, inorganic, stone-forming SiO.sub.2 and Al.sub.2 O.sub.3 containing compositions is accelerated by materials which exhibit exothermic behavior in the presence of water. Such polymerizable compositions are suitable as mortar compositions for fastening anchor rods.

Abstract: Cycloaliphatic compounds, which have one or more ethylenically unsaturated substituents, are disclosed as components of borehole-filling masses, optionally together with other curable components.

Abstract: A deep-borehole drilling device comprising a drive unit such as a downhole motor and a driven unit such as a generator in which a drive transmission coupling is provided in the form of a contact-free magnetic coupling. The magnetic coupling may be a permanent magnet coupling with the magnets arranged coaxially and is preferably a can-tube coupling comprising an outer magnet carrier and a can-tube disposed coaxially within said outer magnet carrier.

Abstract: In a device for the transmission of information from a borehole to the surface during the operation of a drilling device which comprises a rotary drill bit, a tubular housing and a pump which delivers a drilling fluid downwards through the tubular housing, through the rotary drill bit and upwards in the annular space between the tubular housing and the borehole, there is provided a detector arranged in the tubular housing, for detecting information, a processor for converting that information into a sequence of electrical control signals and a transducer for generating pressure pulses in the downwardly-directed flow of drilling fluid as a function of the control signals, and a remote detector arranged at a position spaced from the processor by a wire-less transmission path with a transmitter unit associated with the remote detector at one end of said path and a receiver unit at the other end of said path.