Manufacturing method for ridged paper ejection roller

摘要

A ridged paper ejection roller according to the present invention conveys a paper sheet in cooperation with a plurality of star wheels disposed apart from each other in a width direction of the paper sheet, and includes a rigid main shaft body and a resin body coated on the main shaft body. The resin body integrally includes a plurality of large diameter-regions that work in conjunction with the respective star wheels to hold therebetween and convey the paper sheet, and small-diameter regions other than the large-diameter regions.

主权项

1. A method for manufacturing a ridged paper ejection roller that conveys a paper sheet in cooperation with a plurality of star wheels disposed apart from each other in a width direction of the paper sheet to be conveyed and includes a rigid main shaft body and a resin body coated on the main shaft body, the resin body integrally including a plurality of ridges that work in conjunction with the respective star wheels to hold therebetween and convey the paper sheet, and small-diameter regions that have a smaller diameter than the ridges, the method comprising,
(a) a step of injecting resin into a through-hole of a first metal die while continuously or intermittently moving the main shaft body in the axial direction so as to pass through the through-hole to provide the resin body on the outer surface of the main shaft body, and (b) a step of forming the ridges and the small-diameter regions by a second metal die before the resin body cures, (c) wherein the through-hole of the first metal die includes an upstream hole that has an inner diameter substantially the same as the outer diameter of the main shaft body and is formed in an end wall on an upstream side relative to an insertion direction of the main shaft body, and a downstream hole that has an inner diameter larger than the upstream hole and is formed in an end wall on the downstream side in the insertion direction so as to be positioned adjacent to the upstream hole on the downstream side in the insertion direction, (d) wherein the first metal die is provide with an injection passage for injecting resin into a gap between the inner surface of the downstream hole and the outer surface of the main shaft body, and (e) wherein the second metal die includes a plurality of segments, the segments capable of being in an assembled state so as to compress the main shaft body that has been provided with the resin body in the radially inward direction of the main shaft body and capable of being disassembled in the radial direction of the main shaft body from the assembled state, and (f) wherein the inner surfaces of the segments are provided with depressions or projections for pressing the resin body before curing to form the ridges.