AU2018101473A4

AU2018101473A4 - Improvements relating to cutting devices to make internal keyways, splines and other shapes in blind bores and through bores

Info

Publication number: AU2018101473A4
Application number: AU2018101473A
Authority: AU
Inventors: Martin Forrer
Original assignee: Elmass (australia) Pty Ltd; Elmass Australia Pty Ltd
Current assignee: Elmass (australia) Pty Ltd
Priority date: 2017-11-22
Filing date: 2018-10-02
Publication date: 2018-11-01
Anticipated expiration: 2026-10-02
Also published as: DE202018106045U1; AU2018101473B4

Abstract

3 The documented invention improves the functionality of the device to cut internal 4 keyways in through bores described in Australian Patent 233260 and enables it to 5 cut internal keyways, internal splines, internal hexagans and other internal polygons 6 without alignment errors in through bores and blind bores, by replacing the guide 7 tube and detachable foot piece described in Australian Patent 233260 and with a 8 guide tube (7) that minimises the distance (6) between the lower end of the 9 detachable foot piece (5) to the cutting edge of the cutter that is sliding in the 10 dedicated square tool holding section of the guide tube (7) and has a receiving body 11 (1) with integrated positioning devices (3) and (13), on to which, using several 12 fastening devices (11), an open ended, detachable foot piece (5), having the mating 13 positioning devices (10) and (14), is mounted in a defined position in such a way, 14 that the resulting cutting forces are distributed equally onto the designated area (2) 15 of the receiving body (1) and area (16) of the open ended detachable foot piece (5). -0 4

Description

IMPROVEMENTS RELATING TO CUTTING DEVICES TO MAKE INTERNAL KEYWAYS, SPLINES AND OTHER SHAPES IN BLIND BORES AND THROUGH BORES

The device in Patent 233260 is designed to cut internal keyways in through bores. It can be used to cut splines and other shapes (keyways, splines and other shapes hereinafter called internal polygons), but the detachable foot piece has to be lined up very precisely to avoid alignment errors, because there is no provision to force the position of the detachable foot piece to be in line with the cutter. The undefined position of the detachable foot piece can also create misalignment problems for internal polygons mainly in larger bore sizes or for repetitive production work that requires the replacement of cutters during mass production. Whist it is possible to cut internal polygons in blind bores with this device, its use to do so is restricted due to the large distance between the bottom of the detachable foot piece and the cutting edge of the cutter. To cut internal polygons in blind bores with very limited space below the keyway,special guide tubes, that look similar to the assembled tool, but do not have a detachable foot piece, have to made for each bore size . This is very expensive and requires a lot of space to store these individual guide tubes for blind bores.

The present invention relates to Australian Patent 233260 and improves the overall functionality of this device to cut internal polygons with minimal alignment errors in cylindrical openings of any shape that have either a closed end (hereinafter called blind bore) or an open end (hereinafter called through bore) if mounted on a manual, NC or CNC machine or on any suitable machine tool with a longitudinally displaceable working spindle.

The invention also reduces the required storage space and costs of the existing guide tubes for blind bores and minimises the distance between the lower end of the detachable foot piece to the cutting edge of the cutter that is sliding in the dedicated square tool holding section of the guide tube, the improvement comprising a guide tube and an open ended detachable foot piece that is secured and accurately positioned on it in such a way that it prevents alignment errors of any internal polygon to be cut.

According to the invention, the subsequently documented device replaces the guide tube and detachable foot piece described in patent 233260 with a guide tube having an integrated positioning device on to which an open ended detachable foot piece that interconnects with the above mentioned locating device is mounted to cut internal polygons in through bores and blind bores, which have only a minimal recess, or a small side bore to allow the swarf to fall off, as well as to produce these internal polygons without alignment errors, as far as the device is used in the sense of the patent 233260.

The invention is hereinafter described in a preferred example of embodiment with reference to the accompanying drawing in which:

Fig 1 and Fig.2 show the device that improves the functionality and precision of similar components in Patent 233260 in isometric detached views.

Figure 3 show the two components assembled in isometric view.

The guide tube (7), which works similar as described in patent 233260, has at the lower end a mounting section with a larger diameter (1) (hereinafter called receiving body (1), and one or more locating devices (3) and / or (13) which align the open-ended, detachable foot piece (5) perpendicular to the bore of the workpiece to be machined to prevent alignment errors if the internal polygon when the device is used according to Patent 233260.

The open-ended detatchable foot piece (5) which has a specially shaped cylindrical guide portion whose outer dimensions correspond to the internal dimensions of the shape of the workpiece in which the internal polygon has to be cut slides on the receiving body (1) of the guide tube (7) which has the integrated locating devices (3) alternatively (3) and / or (13) and is mounted through the openings (4) by means of several fastening devices (11) so that the forces generated during the cutting process of the internal polygons are distributed equally onto the designated surface (2) of the receiving body (1) of the guide tube (7) and onto the matching surface (16) of the foot piece (5), wherein for the production of internal polygons a foot piece (5) is used having the external dimensions that correspond to the internal dimensions of the workpiece.

Claims

The claims defining the invention are as follows: 1) A device to make internal polygons in blind bores and in through bores, characterized in that, compared to the patent 233260, the distance (6) between the lower end (15) of an open-ended, detachable foot piece (5) and the cutting edge of the cutting tool sliding in the square tool holding section of the guide tube (7) is considerably reduced,and one or more locating devices (3), and / or (13) which align the open ended, detachable foot piece (5) perpendicular to the bore of the workpiece to be machined to prevent alignment errors.
2) An device according to claim 1), characterized in that the lower end of the guide tube (7) is provided with two sections, firstly a receiving body (1) which distributes any horizontal and vertical forces that occur during production of internal polygons equally to the designated areas (2) of the receiving body (1) and (16) of the open ended, detachable foot piece (5), precisely aligns the open ended, detachable foot piece (5) using its ingegrated positioning devices (10) and / or (14) and allows the open ended, detachable foot piece (5) to be securely mounted on it by means of the fastening devices (11), and secondly, a smaller cylindrical part (8) which slides into the mating, cylindrical opening (12) of the open ended, detachable foot piece (5).
3) A device according to an above mentioned claim, characterized in that the receiving body (1) has a segment (9) which minimizes the required recess below internal polygons in blind bores and at the same time provides sufficient space to receive the heads of the fastening devices (11).
4) An open ended, detachable foot piece (5) according to an above mentioned claim having an external diameter that corresponds to the internal diameter of the bore in which the internal polygon is to be made,characterised in that the open ended, detachable foot piece (5) is precisely aligned by its integrated positioning devices (10) and / or (14) together with the mating positioning devices (3) and / or (13) of the receiving body (1) so that the cylindrical opening (12) of the open ended, detachable foot piece (5) slides over the cylindrical part (8) of the guide tube (7) until the lower ends (15) of the open ended, detachable foot piece (5) and (8) of the guide tube (7) lie on the same plane and is mounted through the openings (4) by means of several of fastening devices (11) on to the receiving body (1) of the guide tube (7), that the horizontal and vertical forces generated in the production of internal polygons are transmitted evenly to the surface (2) of the receiving body (1) of the guide tube (7) and to the mating surface (16) of the open ended, detachable foot piece (5).
5) A device according to an above mentioned claim, characterized in that it is substantially described with references to and illustrated in Figures 1 - 3 of the accompanying drawings.