Patent · US Expired

Paper-punching device for use in an image-forming apparatus

US5839336A · kind A · utility

12Cited by
6References
18Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 17, 1996
Grant dateNov 24, 1998
Priority date
Expiry dateDec 17, 2016

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T83/8743
  • WIPO fieldMachine tools
  • WIPO sectorMechanical engineering

Abstract

In a paper-punching device for use in an image-forming apparatus, the rear edge of a sheet of paper that is being transported through a transport guide is detected by the photosensor. After a predetermined time has passed since the detection, a punching device is activated. At this time, a punching member is depressed downward, and a punching blade attached to its top penetrates through the sheet of paper, thereby forming a punch hole. Even during the punching operation, transport rollers continue to rotate. Therefore, when the sheet of paper is caught by the punching blade, the transport rollers are allowed to slip a predetermined amount with respect to the paper. For this reason, at least one of the transport rollers is made of a foamed material. With this arrangement, since the punching operation is carried out on the rear side of the sheet of paper, it becomes possible to reduce the occurrence of paper jams even if sheets of paper are transported in succession. Further, the punching operation is carried out while the paper is being transported; this makes it possible to provide a high-speed operation. Further, even if the sheet of paper is caught by the punching blade, it is no…

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