System on a bookbinding machine, to permit actuator-effected positioning of machine elements for book block format changing

摘要

An external electronic measuring apparatus 2 in which a sample book block 1 is clamped and the thickness is then determined as a displacement- dependent actual value. The apparatus further includes a microprocessor 20 in which the actual displacement value is evaluated, and is stored as a required value, and a control unit 19 for transmitting the required value to the actuators 44, 45, as an actuating variable. The measuring apparatus possesses a clamping device 8, 9 which can be driven by a motor, and which enables two or more actual displacement values to be determined, these values being functions of differing compressive forces which serve to hold the book blocks in the bookbinding machine 42. These actual displacement values are defined by switch arrangements 20, 38, 13, and 39, as pressure points P1, P2 . . . Pn, and are determined, as actual displacement values, by means of a displacement measuring facility 31-35, in a sequentially controlled procedure. The displacement values are commensurate with the exceedance of a predetermined, required compressive force, defined by a first spring means 14, and the exceedance of a predetermined, required force, defined by a second spring means 17.