GB2417703A

GB2417703A - Head and holder for a rotary cutting etc and/or burnishing

Info

Publication number: GB2417703A
Application number: GB0419220A
Authority: GB
Inventors: Paul Tirre
Original assignee: Cogsdill Nuneaton Ltd
Current assignee: Cogsdill Nuneaton Ltd
Priority date: 2003-09-11
Filing date: 2004-08-31
Publication date: 2006-03-08
Also published as: GB0419220D0; GB0321264D0

Abstract

A head 1 for use in rotary machining operations, comprises a body member (fig 1, 2) having a longitudinal axis of rotation 3 and at one end (fig 1, 4) a coaxial shank 5 adapted to be clamped in a chuck or arbor of a machine tool. A blind bore (fig 1, 16) extends into the body member (fig 1, 2) from its other end 17 and has a bore axis 18 that is not coaxial with the longitudinal axis 3 and a cylindrical slide 20 is located within the bore 18 with a key 21 and keyway 22 to restrain rotation of the slide. A further blind bore 23 is provided in the slide 20, which bore 23 is coaxial with the axis 3 and is adapted, in use, to receive a shank. Spring 6 serves to bias the slide 20 and a retention means 30 restrains the slide within the bore 18. The invention also includes a holder 32 for a rotary cutting/chamfering/recessing, deburring tool 45 or a burnishing tool 33.

Description

1 241 7703

Title of the Invention

Head and holder for a rotary cutting etc and/or burnishing tool

Field of the Invention

This invention relates in one aspect to a head, and in another aspect to a holder adapted in use to be secured at one end in a chuck or arbor of a machine tool, and adapted at its other end to hold a cutting/chamfering/recessng/de-burring tool and/or burnishing tool.

Background of the Invention

In the production of chamfers for instance on holes and slots in components lo or workplaces it is frequently the case that in a standard range of recess heads or chamfering tools the latter are of limited use in that they are oversized for the workplace involved, or may only be capable of generating small fixed precise chamfers, or may be inefficient in workplaces of softer materials.

Object of the Invention A basic object of the invention is the provision of an improved head, and an improved holder for a rotary cutting etc and/or burnishing tool.

Summary of a First Aspect of the Invention

According to the present invention, there is provided a head for use in rotary machining operations such as cutting, chamfering, recessing, deburring or so burnishing, comprising: (i) a body member having a longitudinal axis of rotation and at one end a coaxial shank adapted to be clamped in a chuck or arbor of a machine tool; (ii) a blind bore extending into the body member from its other end having a bore axis that is not coaxial with the longitudinal axis of the body member, so as to define an inclined plane; (iii) a cylindrical slide located within the inclined bore with a key and keyway between the slide and Inclined bore to restrain rotation of the slide; (iv) a blind bore provided in the slide, which blind bore is coaxial with the axis of rotation of the body member and is adapted, in use, to receive a shank of an s adaptor in or on which is securable, as required, a cutting tool or a burnishing roller, with means to retain the adaptor shank with respect to the slide; (v) means to bias the slide away from the shank of the body members; and (v') a slide retention means to restrain the slide within the inclined bore under the influence of the biasing means and to close of partially the otherwise open lo end of the Inclined bore.

Summary of a Second Aspect of the Invention

According to a second aspect of the invention, there is provided a holder for a rotary cutting/chamfering/recessing, de-burring tool or a burnishing tool, comprising: (i) a body member having a longitudinal axis of rotation and at one end a coaxial Is shank adapted to be clamped in a chuck or arbor of a machine tool; (ii) a blind bore extending into the body member from its other end having a bore axis that is not coaxial with the longitudinal axis of the body member, so as to define an inclined plane; (iii) a cylindrical slide located within the inclined bore with a key and keyway between the slide and Inclined bore to restrain rotation of the slide; (iv) a blind bore provided in the slide, which blind bore is coaxial with the axis of rotation of the body member and is adapted, in use, to receive a shank of an adaptor in or on which Is securable, as required, a cutting tool or a burnishing roller, with means to retain the adaptor shank with respect to the slide; as (v) means to bias the slide away from the shank of the body members; (vi) a slide retention means to restrain the slide within the inclined bore under the influence of the biasing means and to close off partially the otherwise open end of the inclined bore; and (vii) a tool holder secured in the slide with a pilot nose provided at an end of the tool holder remote from the slide and providing a thrust face adapted to bear on a face of a workplace Advantage(s) of the Invention In use, the tool holder of the holder in accordance with the second aspect is fitted with a tool such as a cutting tool or burnishing roller, depending on the lo operation required and the holder is secured in a chuck or arbor of a machine tool.

With the slide, under the influence of its biasing means displaced to the outer end of the inclined bore, the holder Is advanced such that the thrust face of the pilot nose is slightly spaced e.g. by 0.5mm, from an adjacent face of the workpiece. The spindle of the machine tool is then started to touch the thrust face on the face of the Is workpiece, and the machine stop to finish stroke positions are set. The holder is then fed e. g. at 0.8mm/rev, towards the workpiece, during which feed the slide moves down the inclined plane to provide radial movement to the cutting tool or burnishing roller.

Thus, unlike conventional tooling systems in which a cutting tool is driven go from the hole to be chamfered, the cutting tool of the holder of the invention does not touch the bore of the hole to be chamfered.

In addition, the cutting tool of the holder of the invention can full form much larger chamfers than conventional tooling systems when tolerances are not so critical.

Preferred or Optional Features The head is provided with a coaxial bore.

The coaxial bore is a blind bore.

The coaxial bore extends Into the shank.

The coaxial bore is closed off at the shank end by a set screw fitted into a tapped hole.

The biasing means comprises a coil compressor spring.

A dowel is slidably located within the coaxial bore and at one end is engaged by one end of the coil compression spring, and at the other end engages an inner lo end of the cylindrical slide.

Engagement of the dowel with the slide is by a pilot nose on the dowel engaging a circular hole in the inner end of the slide.

The slide retention means comprises at least one split washer itself retained by a circlip.

Is A plurality of differing slide tool holders are provided, which are readily interchangeable, to convert between cutting and burnishing operations.

A plurality of cutters are provided for receipt in the tool holder to suit whatever chamfering or recessing operation is required.

A plurality of interchangeable rollers are provided to suit the hole burnishing so required.

A variable pressure pre-loading arrangement is provided to suit various applications.

Drawings Various embodiments are shown by way of example only in the accompanying drawings, in which: Figure 1 is an axial sectional view of a head in accordance with the first aspect of the invention; Figure 2 is an axial sectional view through a first embodiment of holder in accordance with the second aspect; Figures 3A and 3B correspond to Figure 2 but show two operational positions of a second embodiment; Figures 4A and 4B correspond to Figure 2, but show two operational positions of a third embodiment; Figures 5A and 5B correspond to Figure 2 but show two operational positions lo of a fourth embodiment; and Figures 6A and 6B correspond to Figure 2 but show two operational positions of a fifth embodiment.

In all Figures, like reference numerals are accorded to like components.

In Figure 1, a head 1 (for use in rotary machining operations such as cutting, chamfering, recessing, de-burrng or burnishing), comprises a body member 2, having a longitudinal axis of rotation 3 and is provided at one end 4 a coaxial shank adapted to be clamped in a chuck or arbor (not shown in Figure 1) of a machine tool A coil compression spring 6 is located within a coaxial bore 7 in both the body member 1 and the shank 5, with an end of the bore 7 provided with a tapped hole 9 into which is screwed a set screw 10 to close off that end of the bore 7 and to engage one end of the coil compression spring 6. The other end 11 of the coil compression spring 6 engages an end 12 of a dowel 13, which is slidably located within the coaxial bore 7, the other end 14 of the dowel being provided with a pilot nose 15. A blind bore 16 extends into the body member 1 from its other end 17, and as has a bore axis 18 that is not coaxial with the longitudinal axis 3 of the body member 1, so as to define an inclined plane 19. A cylindrical slide 20 is located within the bore 16 with a key 21 and keyway 22 between the slide 20 and bore 16 to restrain rotation of the slide 20 within the bore 16. A blind bore 23 is provided in the slide 20, which blind bore 23 is coaxial with the axis of rotation 3 of the body member 2 and is adapted, in use, to receive a shank (not shown in Figure 1) of an adaptor in, or on, which is securable, as required, a cutting tool or a burnishing roller. The slide 20 is provided with a radially extending tapped hole 24 in which is located a set screw 25 adapted to engage the above mentioned shank. An end wall 26 of the slide 20 is provided with a circular aperture 27 adapted to be engaged by the pilot nose 15.

lo Consequently, the spring 6, via the dowel 13, biases the slide 20 away from the shank 5.

Multiple split washers 28,29, themselves retained by a circlip 30, serve to restrain the slide 20 within the bore 16 under the influence of the spring 6 and to close off, partially, the otherwise open end of the bore 16.

In Figure 2, the head 1 of Figure 1, is fitted by its shank 5 into a drive spindle 31 of a machine tool to constitute a holder 32 for a burnishing tool 33.

Securing of the shank 5 is by four set screws 34 located in radially extending tapped holes 35, whilst the coil compression spring 6 of Figure 1 is replaced in this embodiment by a pack 36 of disc springs to provide the necessary bias.

no Fitted into the blind bore 23 of the slide 20 and secured by set screw 25, is a shank 37 of a spindle 38 of the burnishing tool 33, the latter also Including a thrust bearing 39 and a needle roller bearing 40 on which is a high speed steel burnishing roll 41 retained by a screw 42 passing into a tapped hole 43 in a portion 44 of the spindle 38 Figures 3A and 3B show the head 1 of Figure 2 fitted with a chamfering tool 45, Figure 3A illustrating the "start" machining position for providing chamfers on corners 46,47 of a workplace 48, and Figure 3B illustrates the "finish" position, with the slide 20 having moved along the included plane 19 against the bias of the spring pack 36 by the machine tool (not shown) feeding the holder 32 e.g. at 0.8mm/re towards the workplace 48 in the direction of arrow A, during which feed of the slide gradually moves from a position defining "start" gap 6 (Figure 3A) to define a "finish" gap 9 (which may be minimal or zero), as cutting tools 49,50 of the tool 45 remove metal from the corners 46,47.

lo Figures 4A and 4B are very similar to Figures 3A and 3B, but show the cutting of chamfers 50 on both outer edges 51 of a general "Z"-shaped slot 52 provided in Figures 5A and 5B are very similar to Figures 4A and 4B, but show a tool 45 in the form of a carbide cutter for cutting a chamfer 50 on one outer edge 51 of a Is hole 53, secured by a grub screw 54 in an adaptor 55 having a shank 37 with a grub screw 56 secured in the blind bore 23 of the cylindrical slide 20 by the grub screw 25.

Figures 6A and 6B are very similar to Figures 4A and 4B, but show a different tool 45 for cutting chamfers 50 on both outer edges 51 of a hole 53 of workplace 48, so while a stop collar 57 is secured to shank 37 by a grub screw 58.

Claims

1. A head for use in rotary machining operations such as cutting, chamfering, recessing, de-burring or burnishing, comprising: (i) a body member having a longitudinal axis of rotation and at one end a coaxial shank adapted to be clamped in a chuck or arbor of a machine tool; (ii) a blind bore extending into the body member from its other end having a bore axis that is not coaxial with the longitudinal axis of the body member, so as to define an inclined plane; (iii) a cylindrical slide located within the inclined bore with a key and keyway lo between the slide and inclined bore to restrain rotation of the slide; (iv) a blind bore provided in the slide, which blind bore is coaxial with the axis of rotation of the body member and is adapted, in use, to receive a shank of an adaptor in or on which is securable, as required, a cutting tool or a burnishing roller with means to retain the adaptor shank with respect to the slide; (V) means to bias the slide away from the shank of the body members; and (vi) a slide retention means to restrain the slide within the inclined bore under the influence of the biasing means and to close of partially the otherwise open end of the inclined bore.

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2. A head as claimed in Claim 1 provided with a coaxial bore.

3. A head as claimed in Claim 1 or Claim 2, wherein the coaxial bore is a blind bore.

4. A head as claimed in Claim 2, wherein the coaxial bore extends into the shank.

5. A head as claimed in Claim 2 or Claim 4, wherein the coaxial bore is closed s off at the shank end by a set screw fitted into a tapped hole.

6. A head as claimed In any preceding claim, wherein the biasing means comprises a coil compressor spring.

lo

7. A head as claimed in Claim 6, wherein a dowel is slidably located within the coaxial bore and at one end is engaged by one end of the coil compression spring, and at the other end engages an inner end of the cylindrical slide.

8. A head as claimed In Claim 7, wherein engagement of the dowel with the slide is by a pilot nose on the dowel engaging a circular hole in the inner end of the slide.

9. A head as claimed in any one of Claims 1 to 8, wherein the slide retention means comprises at least one split washer, itself retained by a circlip.

10. A head substantially as herein before described with reference to Figure 1 of the accompanying drawings.

11. A holder for a rotary cutting/chamfering/recessing, de-burring tool or a burnishing tool, comprising: (i) a body member having a longitudinal axis of rotation and at one end a coaxial shank adapted to be clamped in a chuck or arbor of a machine tool; (ii) a blind bore extending into the body member from its other end having a bore axis that is not coaxial with the longitudinal axis of the body member, so as to define an inclined plane; (iii) a cylindrical slide located within the inclined bore with a key and keyway between the slide and inclined bore to restrain rotation of the slide; lo (iv) a blind bore provided in the slide, which blind bore is coaxial with the axis of rotation of the body member and is adapted, in use, to receive a shank of an adaptor in or on which is securable, as required, a cutting tool or a burnishing roller, with means to retain the adaptor shank with respect to the slide; Is (v) means to bias the slide away from the shank of the body members; (vi) a slide retention means to restrain the slide within the inclined bore under the influence of the biasing means and to close off partially the otherwise open end of the inclined bore; and (vii) a tool holder secured in the slide with a pilot nose provided at an end go of the tool holder remote from the slide and providing a thrust face adapted to bear on a face of a workpiece.

12. A holder as claimed in Claim 11, wherein a plurality of differing slide tool holders are provided, which are readily interchangeable, to convert between cutting and burnishing operations.

13. A holder as claimed in Claim 11 or Claim 12, wherein a plurality of cutters are provided for receipt in the tool holder to suit whatever chamfering or recessing operation is required. s

14. A holder as claimed in any one of Claims 11 to 13, wherein a plurality of interchangeable rollers are provided to suit the hole burnishing required.

15. A holder as claimed in any one of Claims 11 to 14, wherein a variable lo pressure pre-loading arrangement is provided to suit various applications.

16. A holder substantially as herein before described with reference to Figure 2 of the accompanying drawings.

17 A holder substantially as herein before described with reference to Figures 3A and 3B of the accompanying drawings.

18. A holder substantially as herein before described with reference to Figures 4A and 4B of the accompanying drawings.

19. A holder substantially as herein before described with reference to Figures 5A and 5B of the accompanying drawings.

20. A holder substantially as herein before described with reference to Figures 6A us and 6B of the accompanying drawings.