Device for applying thread staples to folded sheets

US4294182A · kind A · utility

Assignee

• VEB Kombinat Polygraph Werner Lamberz Leipzig · DE

Inventors

• Winfried Böttcher · Leipzig, DE
• Kurt Germer · Leipzig, DE

Key dates

• Filing date: Sep 13, 1979
• Grant date: Oct 13, 1981
• Expiry date: Sep 13, 1999

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B42B4/00
• WIPO field: Other consumer goods
• WIPO sector: Other fields

Abstract

The device for piercing thread staples into folded sheets travelling in a plane includes an endless chain travelling at the same speed above the sheet feeding plane and supporting at regular intervals thread feeding plates which in turn support for a reciprocating movement a needle carrier with two needles having bifurcated points for engaging a thread length in the plate. The needle carrier supports two cam following rollers cooperating, respectively, with a stationary cam assembly above the chain. The cam assembly includes a lower cam for imparting a lifting movement to the needle carrier and a pivotable upper cam for imparting a lowering movement to the carrier against the sheet to be stitched. The upper cam cooperates with a solenoid which urges the same into its working position, and with a tensioning spring which urges the cam into its inoperative position against the force of the solenoid. A switch deactivates the solenoid when the upper cam is displaced by the resistance of the needles toward its inoperative position.