Apparatus for controlling a pipe-cutting device

In a continuous spiral pipe winding machine having a winding spindle for winding a band of sheet material and a cutting member operatively mounted on a sled which is movable reciprocally along said winding spindle which cutting member advances along said winding spindle during operation at the same speed as the advancing movement of the formed pipe, an arrangement for controlling the advancing speed of said cutting member toward said winding spindle in dependence with the feed speed of said band of sheet material, comprising in combination,

• a guide roller rotatably mounted in said machine over which said band of sheet material is guided;
• a pulse emitter operatively connected to said guide roller;
• drive means mounted in said machine for reciprocally moving said cutting member toward said spindle;
• and AND/OR-value-comparator stage having a pulse counter and an AND/OR-comparator, said pulse emitter being operatively connected to said pulse counter;
• and said AND/OR-comparator being operatively connected to said drive means, the outpulses of said comparator being conducted to said drive means thereby determining the speed of movement of said cutting member toward said spindle;
• said AND/OR-value-comparator stage has an OR-value input stage, and computer means being operatively connected to said pulse emitter, on the one hand, and said OR-value input stage, on the other hand;
• said computer receiving and processing pulse sequences which are being emitted in accordance with the width B of the band and the running-in angle .alpha. of the band with respect to the spindle.