DEVICE FOR DETECTING BENDING ANGLE OF WORKPIECE IN PRESS MACHINE

摘要

PURPOSE:To catch precisely an bending angle of workpiece while processing and to feed it back to obtain a precision product by providing a means for detecting an rocking angle to one axis at the punch side. CONSTITUTION:A workpiece W is placed on a die 3, which is raised to bring the workpiece W into contact with the lower end P of a punch 1 and the lower end S of a workpiece contactor 9 to bend the workpiece W from this position. The workpiece W is bent into a V-shape, and the lower end S of contactor 9 is pushed upward; then by arms 5, 7, the contactor 9 is displaced, parallelly to the vertical engaging line of the punch 1 and die 3 and slantly upward, to the position 9', and the lower end S is displaced to the S' position. The arms 5, 7 are displaced respectively at the same time to the positions 5', 7', and are rotated from the original positions by an angle equal to the bent angle theta of the workpiece W. The rotating angle is transmitted to an encoder 17 through pulleys 11, 13 and a belt 15 respectively to indicate an output of encoder 17 by an angle with the aid of a counter.