Automatic control device for a bending machine

An automatic bending machine for producing different types of loops in a trial-run free manner from a continuous wire comprising, in combination:

• a feeding station including means for guiding said rod along a feeding path, and wire shearing means;
• a bending unit including a mandrel and a bending tool angularly displaceable about an axis of rotation in opposite directions in said feeding path, displaceable in a direction perpendicular to said axis of rotation, and axially displaceable from said feeding path;
• a power drive circuit including a plurality of reversible power drive units and switching units for actuating said feeding station and said bending unit;
• and
• a programmable control device including a plurality of program units, each having a basic fixed program determining the direction of bending and the magnitude of angles of successive bends for different types of the loop to be produced, a loop-type preselector for activating a selected one of said program units, a length-of-sides selector programmable for determining the length of successive sides of the selected loop, data processing means for comparing actual values measured on the loop in process with programmed values and for producing a succession of control signals applied to said power drive circuit to control the direction of travel and shearing of said wire by said shearing means in said feeding station, and the angular and axial displacements and change of direction of rotation of said mandrel and bending tool in said bending unit in accordance with the selected program and in response to the measured actual value.