Patent · US Expired

Variable force sheet feeding mechanism

US3989237A · kind A · utility

9Cited by
6References
26Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 5, 1975
Grant dateNov 2, 1976
Priority date
Expiry dateMay 5, 1995

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB65H3/02
  • WIPO fieldHandling
  • WIPO sectorMechanical engineering

Abstract

A buckling type paper sheet feeding mechanism wherein the top sheet of a stack is separated from the underlying sheet by first driving the front sheet edge in a rearward direction against a rear restraint, causing the top sheet to buckle, and then reversing the direction of sheet drive, causing the top sheet to be fed in a forward direction over a front stack edge restraining or hold-down means. The top sheet is moved rearward by a variable force means which provides a progressively increasing buckling force, to thereby ensure reliable feed of paper of varying types, weights and humidity content, while at the same time minimizing the possibility of double sheet feed. A variable position rear restraint moves rearward, in synchronism with operation of the variable force means, to increase the column length of the top sheet as the buckling force increases.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.