Abstract: A driving mechanism, preferably provided for a high-voltage isolating switch (T), contains a driving motor (M) which acts upon a moving contact of the switch via a shaft (W) and is provided with a rotor winding (R) and a stator winding (S), connected in series. To control a direction of rotation of the driving motor (M) in dependence on the position of the switch, the driving mechanism also contains a control circuit. In this driving mechanism, it is intended to keep the number of cores of a connecting cable (L) from the driving mechanism housing (K) to a control cabinet (N) as small as possible.

Abstract: A drive for a high-voltage isolating switch includes a shaft which acts on a moving contact of the isolating switch, a flywheel which is connected via a coupling to the shaft, a drive motor for energizing the flywheel before a switching process begins and a control circuit. The control circuit is used for determining the direction of rotation of the drive motor during the energizing process and for automatically switching the drive motor from a motor to a generator operation, during a period when the movable contact is to be moved. The motor is preferably a series-wound motor which provides high operational reliability. A rectifier is connected in the current path between the rotor and stator windings of the motor. The rectifier stabilizes the current direction in the stator winding during the switching-over phase of the drive motor from motor to generator operation.

Abstract: In a protective circuit layout for a high voltage switchgear installation the switching position of the high voltage switches is detected by position signal contacts (for example Q81NCR, Q81NCS, Q81NCT). The status signals emitted by the position signal contacts of a group of switches (Q81, Q82, Q83, Q0) serve in a logic combination to monitor the command path of a switch (Q91) not belonging to the group. Each of the switches (for example Q91) is provided with a modularizable release unit with an inlet part (FEQ91) and an outlet part (FAQ91) arranged in the command path. At the inlet part (FEQ91) the status signals required for the monitoring of the command path of the associated switch (Q91) are present. At the outlet part (for example FAQ91) the signal emitted by the associated switch (Q91) to the release units of other switches of the switchgear installation may be obtained. In the release unit the status signals effecting the blocking or release of the switch (Q91) to be monitored are processed.

Abstract: During grinding, a grinding wheel effects movements of solely vertical displacement along a path parallel to a vertical guide rod. The workpiece to be machined is held by a rotatable, but not axially displaceable, chuck secured to a workpiece head. In order that helical relative movements between the workpiece and the grinding wheel may be produced, transmission components and gearing are provided for positively converting the vertical motion of the grinding wheel into rotary motion of the workpiece. For cylindrical and surface grinding, the motion-conversion arrangement may easily be disengaged or dismantled. Thus it is possible with this universal grinding machine to carry out drill grinding, cylindrical grinding, and/or surface grinding on a workpiece which need be chucked only once.