Sheet binding device, sheet processing apparatus, and image forming system

Abstract

The invention provides a sheet binding device, a sheet processing apparatus, and an image forming system. The sheet binding device includes: a pair of crimping members each including alternately-arranged multiple recesses and multiple protrusions to bind a sheaf of sheets by fitting the recesses and the protrusions with the sheet sheaf interposed therebetween. When the recesses and the protrusions of the pair of crimping members are fitted, slanted side faces of the protrusions of one of the pair of crimping members and that of the other one of the pair of crimping members are in contact with each other with a clearance left both between top portions of the protrusions of the one of the crimping members and bottom portions of the recesses of the other one of the crimping members and between top portions of the protrusions of the other one of the crimping members and bottom portions of the recesses of the one of the crimping members.

Description

[0001] Cross References to Related Applications [0002] This application claims priority from Japanese Patent Application No. 2013-190376 filed in Japan on September 13, 2013, and the entire contents thereof are incorporated by reference. technical field [0003] The present invention relates to a paper binding device, a paper processing apparatus, and an image forming system. Background technique [0004] A conventional known type of image forming system includes a sheet processing apparatus configured to bind a bundle of sheets on which an image is formed by the image forming apparatus using a binding tool as a binding unit. [0005] International Publication No. WO 2009 / 110298 discloses a paper processing apparatus including a crimping type paper binding device which does not use metal staples but by firmly engaging a pair of crimping toothed claws. A bundle of paper is bound by crimping the paper with jaws, which are crimping members each having a shape of a convex por...

AI Technical Summary

Problems solved by technology

This leads to such a disadvantage that the pressure is concentrated to the part of the sheet bundle that contacts the top of the convex portion 171a of the upper crimping dog 261a and damages the sheet(s) of the bundle

[0011] The configuration described in International Publication No. WO 2009 / 110298 is also disadvantageous because breakage of the sheet(s) of the bundle may occur

This is because the fibers are not sufficiently prevented from extending beyond their limits by merely forming a gap between the concave portion 171b of the upper crimping dog 261a and the convex portion 172a of the lower crimping dog 261b.

Images