Patent ID: 8783147
Filing Date: 2014-07-22
Classification: B23D,B26D,B26F,Y10T

Abstract:
1. A nibbling tool adapted to incrementally remove material from an edge of sheet material, the nibbling tool comprising a punch caused in use to reciprocate within a die by drive means, the punch comprising a generally elongate cylindrical member having a first diameter and having a waisted portion disposed towards the work end, the waisted portion defining a second, reduced diameter, the punch having an abrupt change between the second, reduced diameter and the first diameter to define a substantially radial contact surface having a circumferential peripheral cutting edge, the die comprising an elongate guide for guiding reciprocation of the punch and having a slot proximate a work end of the die adapted to expose the punch, the slot adapted in use to receive said edge of the sheet material and positioned along the die so that at one point of the stroke of the reciprocation of the punch the waisted portion of the punch is positioned in the slot and at another point in the stroke a first diameter portion of the punch is positioned within the slot whereby said radial contact surface is caused to reciprocate across the slot, the slot comprising a first support surface and a second support surface opposing the first support surface in a spaced relationship, the punch is adapted to cut the edge of the sheet material as it travels in a first direction from the second support surface to the first support surface, the first and second support surfaces are adapted to provide support to the sheet material such that in use and during an upward stroke of the punch the circumferential peripheral cutting edge of the contact surface of the punch is caused to engage the sheet material and cause it to be pressed against at least the first support surface to cause the incremental removal of material from the sheet wherein the plane of the first support surface is inclined in a second direction opposite the first direction and with the first support surface located in front of the punch when viewed from exterior of the die in a direction perpendicular to a central axis of the punch, wherein the punch and the die are configured such that when the punch engages the sheet material the sheet material is caused to be oriented at an angle relative to the radial contact surface due to the orientation of the first support surface, the circumferential peripheral cutting edge initially contacts the sheet material at two points only at the edge of the sheet material, and as the punch travels in the first direction, the cutting edge causes a progressive cutting action on the material.