A MACHINE REAMING TOOL, INTERCHANGEABLE HEAD AND SHANK FOR A MACHINE REAMING TOOL

Abstract

A machine reaming tool includes a shank and an interchangeable head assembled on the shank. The interchangeable head on a side that faces the shank includes at least one head groove and at least one head ridge. The shank on a side that faces the interchangeable head includes at least one shank groove and at least one shank ridge. In the assembled condition, the at least one head groove engages into the at least one shank ridge and the at least one shank groove engages into the at least one head ridge.

Claims

1. A machine reaming tool comprising a shank and an interchangeable head, which is assembled on the shank, wherein the interchangeable head on a side that faces the shank comprises at least one head groove and at least one head ridge, the shank on a side that faces the interchangeable head comprises at least one shank groove and at least one shank ridge, and in the assembled condition, the at least one head groove engages into the at least one shank ridge and the at least one shank groove engages into the at least one head ridge.

2. A machine reaming tool according to claim 1, wherein the grooves and ridges on the interchangeable head and on the shank each comprise oblique side walls, and in the assembled condition, a fastening element, which presses the interchangeable head in a direction towards the shank, presses the oblique side walls of the head groove against those of the shank ridge and the oblique side walls of the head ridge against those of the shank groove.

3. A machine reaming tool according to claim 1, wherein two inner side walls of the head groove taper to one another in the direction of a base surface of the head groove and form two head groove contact surfaces, and two outer side walls of the head ridge taper to one another in the direction of an end face of the head ridge and form two head ridge contact surfaces; two inner side walls of the shank groove taper to one another in the direction of a base surface of the shank groove and form two shank groove contact surfaces, and two outer side walls of the shank ridge taper to one another in the direction of the end-face of the shank ridge and form two shank ridge contact surfaces; and in the assembled condition, the head groove contact surfaces lie on the shank ridge contact surfaces and the two head ridge contact surfaces lie on the shank groove contact surfaces.

4. A machine reaming tool according to claim 3, wherein the two inner side walls of the head groove are plane, and two planes, in which the two inner side walls of the head groove lie, intersect at a line which intersects the rotation axis and lies normally to this; the two outer side walls of the head ridge are plane, and two planes, in which the two outer side walls of the head ridge lie, intersect at a line which intersects the rotation axis and lies normally to this; the two inner sides walls of the shank groove are plane, and two planes, in which the two inner side walls of the shank groove lie, intersect at a line which intersects the rotation axis and lies normally to this; and the two outer side walls of the shank ridge are plane, and two planes, in which the two outer side walls of the shank ridge lie, intersect at a line which intersects the rotation axis and lies normally to this.

5. A machine reaming tool according to claim 2, wherein the shank ridge comprises a slot in the longitudinal direction and by way of this, in the assembled condition relative to the non-assembled condition, the outer side walls of the shank ridge are pressed against one another, the shank ridge is deformed and the slot is narrowed.

6. A machine reaming tool according to claim 1, wherein the head groove and the head ridge run normally to one another and the shank groove and the shank ridge run normally to one another.

7. An interchangeable head for a machine reaming tool comprising a rotation axis, wherein at a side which is envisaged for assembly on a shank, the interchangeable head comprises at least one head groove and at least one head ridge.

8. An interchangeable head according to claim 7, wherein the head groove and the head ridge each comprise oblique side walls, and in particular two inner sides walls of the head groove taper to one another in the direction of a base surface of the head groove and form two head groove contact surfaces, and two outer side walls of the head ridge taper to one another in the direction of an end face of the head ridge and form two head ridge contact surfaces.

9. An interchangeable head according to claim 8, wherein the two inner sides walls of the head groove are plane, and two planes, in which the two inner side walls of the head groove lie, intersect at a line which intersects the rotation axis and lies normally to this; the two outer side walls of the head ridge are plane, and two planes, in which the two outer side walls of the head ridge lie, intersect at a line which intersects the rotation axis and lies normally to this.

10. An interchangeable head according to claim 8, wherein the inner side walls of the head groove and/or the outer side walls of the head ridge are inclined by an angle of between 10 and 40 respect to the rotation axis.

11. An interchangeable head according to claim 7, with four teeth, with a diameter of 6 mm to 8 mm and with a straight fluting of the teeth, with which a division of the angles between the teeth has the following angles: head ridge to first tooth: 30; first tooth to second one: 92; second tooth to third one: 88; third tooth to fourth one: 95;

12. An interchangeable head according to claim 7, with four teeth, with a diameter of 6 mm to 8 mm and with a helical fluting of the teeth, with which a division of the angles between the teeth has the following angles: head ridge to first tooth: 25; first tooth to second one: 92; second tooth to third one: 88; third tooth to fourth one: 95;

13. An interchangeable head according to claim 7, with six teeth, with which a division of the angles between the teeth has the following angles: first tooth to second one: 63; second tooth to third one: 61; third tooth to fourth one: 56; fourth tooth to fifth one: 60; fifth tooth to sixth one: 55; and with one of the following combinations of diameter d, fluting v and angle w between the head ridge and the first tooth: d=8 mm to 10 mm, v=straight, w=47; d=8 mm to 10 mm, v=helical, w=35; d=9 mm to 11 mm, v=straight, w=50; d=9 mm to 11 mm, v=helical, w=40; d=11 mm to 13 mm, v=straight, w=50; d=11 mm to 13 mm, v=straight, w=40.

14. A shank for a machine reaming tool, comprising a rotation axis, wherein the shank at a side which is envisaged for assembly on an interchangeable head comprises at least one shank groove and at least one shank ridge.

15. The shank according to claim 14, wherein the shank ridge comprises a slot in the longitudinal direction, said slot extending into the shank ridge in a manner proceeding from the end-face of the shank ridge.

16. The shank according to claim 15, wherein a depth of the slot is at least as much as a height of the shank ridge beyond a shank end-face, from which the shank ridge rises.

17. The shank according to claim 14, which is manufactured from steel in a connecting region, on which the shank ridge is formed and is manufactured of a different material, in particular a hard metal, in a rear part of the shank.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0076] The subject-matter of the invention is hereinafter explained in more detail by way of preferred embodiment examples which are represented in the accompanying drawings. Schematically represented in each case are:

[0077] FIG. 1 is an exploded drawing of a machine reaming tool;

[0078] FIG. 2 shows a head-side end of a shank;

[0079] FIG. 3 shows an interchangeable head;

[0080] FIG. 4a-c are views of a blank for an interchangeable head;

[0081] FIGS. 5a-b are views of the head region of the tool;

[0082] FIG. 6a-f show details of the connections between the interchangeable head and the shank;

[0083] FIG. 7 shows a shank and an interchangeable head, in a front view and cross section;

[0084] FIG. 8 shows a shank with four coolant channels;

[0085] FIG. 9 shows a shank with one coolant channel;

[0086] FIG. 10 shows a shank with coolant grooves; and

[0087] FIG. 11-15 are different divisions of coolant feed and teeth.

DETAILED DESCRIPTION OF THE INVENTION

[0088] Basically, the same or equally acting parts are provided with the same reference numerals in the figures.

[0089] FIG. 1 shows an exploded drawing of a machine reaming tool with an interchangeable head 1 and with a shank 2 and with a cap screw 3 for fastening the interchangeable head 1 on the shank 2. The location, at which the interchangeable head 1 bears on the shank 2 is also called the separating location. A rotation axis 31 of the tool is identical to the rotation axis 31 of the shank 2 and of the interchangeable head 1 and is also the longitudinal axis as well as the axis of symmetry of these parts.

[0090] FIG. 2 shows a head-side end of a shank 2, which includes a shank groove 22 and a shank ridge 23 that runs normally to this. Taking the shank end-face 21 as a reference, the shank groove 22 can be considered as a recess and the shank ridge 23 as a projection. The shank groove 22 and the shank ridge 23 run normally to the rotation axis 31. A bore, in particular a threaded bore 24 runs in the direction of the rotation axis 31 in the region, in which the shank groove 22 and the shank ridge 23 cross one another.

[0091] The shank groove 22 at its two sides includes two inner side walls. These are oblique, thus are not parallel to the rotation axis 31, and, proceeding from the shank end-face 21, taper to one another in the direction of a base surface 222 of the shank groove 22.

[0092] The shank ridge 23 at its two ends includes two outer side walls. These outer side walls are oblique and, proceeding from the shank end face 21, taper to one another in the direction of an end-face 232 of the shank ridge 23.

[0093] The side walls of the shank groove 22 and of the shank ridge 23 form contact surfaces 221 of the shank groove 22 and contact surfaces 231 of the shank ridge 23, on which contact surfaces the interchangeable head 1 bears with correspondingly shaped contact surfaces.

[0094] The shank ridge 23 includes a slot 233, which extends along the shank ridge 23 and parallel to the rotation axis 31 of the shank 2 from the ridge end-face 232 into the shank 2. Here, it can extend further into the shank 2 than a plane of the shank end-face 21. The shank ridge 23 can be compressed thanks to the slot 233, i.e. it can elastically deform given an applied interchangeable head 1 and by way of this can compensate inaccuracies in the mutual position of the contact surfaces of the interchangeable head 1 and the shank 2.

[0095] The shank 2 moreover includes coolant channels 25.

[0096] FIG. 3 shows an interchangeable head 1. This head includes a head groove 12 and a head ridge 13, which runs normally to this. Taking the head end-face 11 as a reference, the head groove 12 can be considered as a recess and the head ridge 13 as a projection. The head groove 12 and the head ridge 13 run normally to the rotation axis 31. A bore for receiving the cap screw 3 runs in the direction of the rotation axis 31 in the region, in which the head groove 12 and the head ridge 12 cross one another.

[0097] The head groove 12 at its two sides includes two inner side walls. These are oblique, and thus are not parallel to the rotation axis 31, and, proceeding from the head end-face 11, taper to one another in the direction of a base surface 122 of the head groove 12.

[0098] The head ridge 12 at its two sides includes two outer side walls. These are oblique and, proceeding from the head end-face 11, taper to one another in the direction of an end-face 132 of the head ridge 13.

[0099] The side walls of the head groove 12 and of the head ridge 13 form contact surfaces 121 of the head groove 12 and contact surfaces 131 of the head ridge 12, on which contact surfaces the shank bears with correspondingly shaped contact surfaces.

[0100] The interchangeable head 1 includes several teeth 16, which are distributed about its periphery and which each form a leading cut portion 17 and a guiding portion 18 of the tool, in particular of a reaming tool.

[0101] FIGS. 4a-c show views of a blank for an interchangeable head. The elements described in conjunction with FIG. 3 are present with the exception of the cutting edges.

[0102] FIGS. 5a-b show views of the head region of the tool in a disassembled condition. In the lower view, the elements of the tool are rotated about the rotation axis 31 by 90 with respect to the upper view.

[0103] FIGS. 6a-f show details of the connections between the interchangeable head and the shank, [0104] with views 6a and 6d corresponding to those of FIGS. 5a-b, but in the assembled condition, and [0105] detailed views 6b and 6e shortly before the interchangeable head 1 and the shank 2 contact one another, and [0106] detailed views 6c and 6f with the interchangeable head 1 and the shank 2 in the assembled and pressed-together condition.

[0107] The relative position of the interchangeable head 1 and shank 2 is defined [0108] a) on the one hand by the mutual position of the contact surfaces 121 of the head groove 12 and of the contact surfaces 231 of the shank ridge 23, and [0109] b) on the other hand by the mutual position of the contact surfaces 131 of the head ridge 13 and of the contact surfaces 221 of the shank groove 22.

[0110] The mutual position of the interchangeable head 1 and the shank 2 along the rotation axis 31 and the mutual position along an axis, which runs normally to the direction of the head groove 12 or to the direction of the shank ridge 23, and typically also normally to the rotation axis 31 are defined by the contact surfaces according to a). The mutual position in the direction of the head groove 12 or of the shank ridge 23 is not defined.

[0111] The mutual position of the interchangeable head 1 and the shank 2 along the rotation axis 31 and the mutual position along an axis, which runs normally to the direction of the head ridge 13 or to the direction of the shank groove 22, and typically also normally to the rotation axis 31 are defined by the contact surfaces according to b). The mutual position of the shank groove 22 in the direction of the head ridge 13 or the shank groove 22 is not defined.

[0112] The mutual position along the rotation axis 31 is thus defined twice and is therefore statically over-defined. One of the elements of the system of contact surfaces is realised in a compliant manner for compensating inaccuracies which could lead to problems on account of this static over-defining. In the present example this is the shank ridge 23, for example by way of a slot 233 running along the shank ridge 23 as has already been described. The two contact surfaces 231 of the shank ridge 23 are elastically deformable to one another by way of this.

[0113] FIGS. 6e and 6f show the deformation of the shank ridge 23 on pressing the interchangeable head 1 onto the shank 2. The connection is not yet loaded in FIG. 6e and in FIG. 6f the two halves of the shank ridge 23, which are separated from one another by the slot 233, are deformed by the pressed-on interchangeable head 1. The two halves and inner sides 234 of the slot 233 are moved towards one another by way of this.

[0114] FIG. 6e also shows that a first inclination of the contact surfaces 121 of the head groove 12 can differ from a second inclination of the contact surfaces 231 of the shank ridge 23 (in the non-loaded condition). Here, the inclination is the angle between the plane of the respective contact surfaces and the rotation axis 31. The first inclination can be somewhat larger than the second inclination. The second inclination becomes larger on deformation of the shank ridge 23 and adapts to the first inclination.

[0115] On manufacture of the interchangeable head 1 and the shank 2, the difference of the mentioned first and second inclinations can be achieved by way of the first inclination being manufactured with a minus tolerance as is usually the case, but the second inclination with a plus tolerance.

[0116] This can mean that the first inclination is equal to a nominal angle, for example between 10 and 40 and in particular equal to 20, with a tolerance between 0 and 0.06, and the second inclination is equal to the same nominal angle but with a tolerance between 0 and +0.06.

[0117] FIGS. 7a-b show a shank and an interchangeable head in a front elevation and cross section. An axial bore 26 of the shaft 2 is visible additionally to the already described elements, through which bore coolant can be led to one or more coolant channels 25. The cap screw 3 is screwed into a threaded bore 24 of the shank 2 and presses the interchangeable head 1 onto the shank 2. The cross section of FIG. 7b can correspond to an embodiment according to FIGS. 8a-b with four coolant channels 25 or to an embodiment according to FIGS. 9a-b with only one coolant channel 25. Each tooth 16 can be supplied individually in the case of four coolant channels 25. Here, a discharge of the coolant (with chips) is envisaged through the bore which is reamed.

[0118] If six or more teeth are present, then typically an equal number of six or more coolant feeds respectively are each led to the cutting spaces in front of the teeth.

[0119] The embodiment with only one or possibly also two coolant channels 25 is advantageous for blind holes, since here a region along the periphery of the interchangeable head 1 which is not supplied by the coolant channel or channels 25 can serve for the return of the coolant (with chips).

[0120] FIG. 10 shows a shank 2 in a lateral view (ridge and groove of the separating location are not represented), wherein the coolant channels 25 run out into coolant grooves 27. The coolant grooves 27 run in the longitudinal direction on the outer periphery of the shank in the direction of the interchangeable head or separating location. The coolant grooves 27 form coolant feeds to the interchangeable head 1 in the case of a cylindrical sleeve arranged around the shank.

[0121] FIGS. 11-15 show different divisions of coolant feed and teeth for different diameters. These optimise the initially mentioned criteria. Concerning the diameters, it is a nominal diameter of a blank, from which the finished cutter (insert) having different cutting diameters can be manufactured, which is taken as the basis. An optimal division is represented for the different diameters. In each case, the specified positions of the coolant feed conduits or teeth can vary by +/2 or +/5. The coolant feeds shown here are realised by way of coolant grooves 27, but can also be realised by channels in the shank. A distance between the shank ridge and the coolant feed is also drawn and specified in millimetres in each case. The part of the figures that is indicated by a shows the division for the respective shank. The part of the figures that is indicated by b shows the division for an interchangeable head with straight fluted teeth. The part of the figures that is indicated by c shows the division for an interchangeable head with helically fluted teeth (in particular left helically fluted teeth). The position of the grooves or ridges of the separating location is the reference concerning the specification of the angle. The angles are specified starting from a symmetry line of the shank groove or head ridge, each in the anticlockwise direction with an external view onto the shank or head.

[0122] FIG. 11 shows divisions for an interchangeable head with a nominal diameter of 7 mm, for diameters of the finished cutter of below approx. 7 mm.

[0123] FIG. 12 shows divisions for an interchangeable head with a nominal diameter of 8 mm, for diameters of the finished cutter of approx. 8.1 mm to 6.9 mm

[0124] FIG. 13 shows divisions for an interchangeable head with a nominal diameter of 10 mm, for diameters of the finished cutter of approx 10.1 mm or 9.6 mm to 8.1 mm.

[0125] FIG. 14 shows divisions for an interchangeable head with a nominal diameter of 11 mm, for diameters of the finished cutter of approx. 11.1 to 9.6 mm.

[0126] FIG. 15 shows divisions for an interchangeable head with a nominal diameter of 13 mm, for diameters of the finished cutter of approx. 13.1 to 11.1 mm.

[0127] The angles of the divisions on the shank in the case of interchangeable heads with four teeth:

TABLE-US-00001 nominal diameter of the interchangeable head 7 mm 8 mm shank groove 22 to the first 40 45 coolant feed first coolant feed to the second 100 90 one second coolant feed to the third 80 90 one third coolant feed to the fourth 100 90 one

[0128] The angles of the division on the respective interchangeable heads are:

TABLE-US-00002 nominal diameter d/fluting v 7 mm/ 7 mm/ 8 mm/ 8 mm/ straight helical straight helical w: head ridge 13 to the first tooth 30 25 30 25 (primary cutting edge) first tooth to second one 92 92 92 92 second tooth to third one 88 88 88 88 third tooth to fourth one 95 95 95 95

[0129] The angles of the divisions on the shank in the case of interchangeable heads with six teeth:

TABLE-US-00003 nominal diameter of the interchangeable head 10 mm 11 mm 13 mm shank groove 22 to the first 0 0 0 coolant feed first coolant feed to the second 50 55 55 one second coolant feed to the third 80 70 70 one third coolant feed to the fourth 50 55 55 one fourth coolant feed to the fifth 50 55 55 one fifth third coolant feed to the 80 70 70 sixth one

[0130] The angles of division on the respective interchangeable heads are:

TABLE-US-00004 nominal diameter 10 mm/ 10 mm/ 11 mm/ 11 mm/ 13 mm/ 13 mm/ d/fluting v straight helical straight helical straight helical w: head ridge 47 35 50 40 50 40 13 to the first tooth (primary cutting edge) first tooth to the 63 63 63 63 63 63 second one second tooth to 61 61 61 61 61 61 the third one third tooth to 56 56 56 56 56 56 the fourth one fourth tooth to 60 60 60 60 60 60 the fifth one fifth tooth to 55 55 55 55 55 55 the sixth one