Maag Gear-wheel & Machine Company Limited

Fritz Loehrer

Guy-Francois Blanc

A grinding wheel support, for instance of a large gear grinding machine, moves up and down during the grinding operation in a non-horizontal guide and is driven by a linear motor which does not possess any self-locking action, for instance a piston-and-cylinder arrangement which is powered by a pressurized oil pump. A brake retains the grinding wheel support in its rest position. During the transition from the rest position into the position-regulation mode the grinding wheel support must not carry out any uncontrolled or undesired movements. Therefore, the grinding wheel support, starting from the time that it is placed into operation out of its rest position, is allowed a certain upward movement play, in order to render possible a surge-free placement into operation of the actual position regulation operation of the position regulator. For this purpose a position measuring system measures a starting position-actual value in the rest position, to which there is added a part of the movement play by means of a set value former, in order to thus define a starting position-set or reference value. The position regulator then controls the pump until the grinding disk support has reached the starting position-set value under the action of the linear motor. At this point in time the brake is released and there can begin the actual position regulation operation.

Arrangement for starting-up a position regulator of a grinding wheel

Two rolling bands, meaning windable and unwindable bands, are affixed to a carriage or slide which is reciprocatingly movable along a guideway. The rolling bands are each arranged to be rolled-off from a respective drum journaled at each end of the guideway. A respective wheel is rigidly coupled to each one of the drums. Two belts interconnected by a tension spring are each arranged to be wound-up upon a respective one of the wheels in opposite direction to the winding direction of the rolling band on the related drum. Without itself being subjected to substantial loading and elongation differences, the tension spring continuously holds both of the rolling bands under tension.

Growing community of inventors

Bach, Switzerland

Fritz Loehrer