Method for direct screwing of structural components, in particular for flow hole screwing and device for direct screwing of structural components

US9901974B2 · kind B2 · utility

Assignee

• DEPRAG Schulz GmbH u. Co. · DE

Inventors

• Rolf Pfeiffer · Amberg, DE
• CARSTEN ROSENKRANZ · Amberg, DE

Key dates

• Filing date: May 13, 2015
• Grant date: Feb 27, 2018
• Expiry date: Jun 10, 2036

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T29/5307
• WIPO field: Machine tools
• WIPO sector: Mechanical engineering

Abstract

A method for direct screwing, in particular flow hole screwing, includes producing a hole in a first stage in a structural component without cutting and forming a thread with a flow hole screw in a second stage. A feed and feed force are produced by a non-pneumatic feed drive and transmitted to a screw shaft rotated by high feed force and high rotational speed in the first stage and at a defined switchover point with penetration of the structural component a switchover is made to the second stage with lower feed force and slower rotational speed. A drive parameter correlated to the feed force, especially a motor current of an electric motor of the feed drive, is monitored and a characteristic change of this parameter is defined as switchover point. A rapid switchover with process stability is attained and damage to the flow hole screw thread is avoided.