Abstract: A roll crusher has at least two crushing rolls and at least two drive trains for the driving of the crushing rolls. The drive trains have each at least one gear for the reduction of the motor speed and a corresponding increase of the torque. The synchronization takes place on a faster-running side of the gear, i.e., the side with lower torque, such that advantageously markedly lower torques are transmitted. The synchronization may be markedly more compact and thus more cost-effective, since markedly lower torques have to be transmitted. The synchronization may have a variety of designs including a simple connection of input shafts of the gears to one another to synchronize them with a corresponding arrangement. The synchronization may thus advantageously be designed for markedly lower torques and thus be markedly more compact in dimensions and be dimensioned more cost-effectively.

Abstract: An overload protection device for operating machines, the device having two coupling parts which are in one condition, a coupled condition, force-interlocked by coupling bodies, until a threshold force is exceeded, at which point coupling is released. The coupling parts have mutually facing surfaces provided with depressions and guide grooves for the coupling bodies. The coupling bodies are rolling elements, e.g., spheres, which when threshold force is overcome, move into the guide grooves causing release of the coupling parts from force-interlock thereby permitting rotational movement of the parts relative to each other.

Abstract: A To facilitate manipulation of an impact member 20 of a coarse reduction impact crusher, the impact member 20 together with its wedge members 22 is only loosely inserted in an accommodating cavity 14 for the impact member, whereby when rotation of a rotor 10 is started the impact member 20 and wedge members 22 are urged by the resulting centrifugal force from a disengaged position near the axis of the rotor into a wedged position relatively distant from said axis.