Abstract: A pressing device for joining workpieces has a pressing tool and a motorized drive for actuation of the pressing tool over a pressing distance, as well as a control device which has a drive control device for influencing the drive. The drive control device has a malfunction detection device which has an actual value sensor which is suitable for detecting, as the actual value, a physical magnitude which is correlated with the pressing resistance. At least one limit value profile for the actual value is retained in the malfunction detection device, and it has a comparison device which, during a pressing, checks whether the particular actual value lies on the permissible or impermissible side of the pertinent limit value profile. The malfunction detection device comprises a signal device and/or a shutdown device for the drive, which are/is activated if the actual value lies on the impermissible side of the pertinent limit value.
Type:
Grant
Filed:
February 20, 1998
Date of Patent:
June 5, 2001
Assignee:
Novopress GmbH Pressen und Presswerkzauge & Co. KG