KIT TO ASSIST IN THE MANUAL CHANGE OF A TOOL FROM A ROTARY TOOL HOLDER

Abstract

A known rotary tool holder (10) comprises a rotary tool gripper (11) and a non-rotary part (16) presenting a flat front wall (18), the rotary tool gripper projecting from the flat front wall and comprising a shaft segment (15) having two shaft flats (12, 13). A kit to assist in the manual change of a tool from such a rotary tool holder comprises a forked holding element (20) provided with two fingers (22, 23) that are suitable to be fitted by their inside on the two shaft flats, and a locking plate (30) that comprises a recess (31) and is suitable to be fixedly mounted on the front wall with the recess facing it, said recess being configured to house the two fingers fitted on the two shaft flats when the locking plate is mounted on the front wall, the recess extending across the locking plate and being delimited by two steps (32, 33) against which the two fingers can be fitted by their outside.

Claims

1-15. (canceled)

16. A kit to assist in the manual change of a tool from a tool holder, the latter comprising a rotary tool gripper and a non-rotary part presenting a flat front wall, the rotary tool gripper projecting from the flat front wall and comprising a shaft segment that is provided with two shaft flats and defines an axial direction, the kit comprising a forked holding element provided with two fingers, each of which has an inside surface and an outside surface, so that the two respective inside surfaces face each other and each outside surface has an orientation substantially opposite to that of its corresponding inside surface, each finger being suitable to be fitted by its inside surface on one shaft flat, and a locking plate that comprises a recess and is suitable to be fixedly mounted on the flat front wall with the recess facing it, said recess being configured to house the two fingers fitted on the two shaft flats when the locking plate is mounted on the flat front wall, the recess extending across the locking plate and being delimited by two steps against which the two fingers can be fitted by their outside surfaces.

17. The kit according to claim 16, wherein the fingers are suitable to fit in the axial direction when they are housed in the recess.

18. The kit according to claim 17, wherein the holding element comprises a handle that is located opposite the fingers.

19. The kit according to claim 18, wherein the part of the fingers in the holding element is U-shaped.

20. The kit according to claim 16, wherein the locking plate is a unitary piece that comprises a hole with a diameter greater than the diameter of the tool gripper.

21. The kit according to claim 16, wherein the locking plate comprises two pieces configured to be joined around the tool gripper and simultaneously mounted on the flat front wall.

22. The kit according to claim 16, comprising a spacer configured to be fixedly mounted on the non-rotary part of the tool holder.

23. The kit according to claim 22, wherein the spacer comprises a flat front wall and the locking plate is configured to be mounted on said flat front wall.

24. The kit according to claim 16, wherein the locking plate comprises at least one internal conduit to convey a cooling liquid to the tool.

25. The kit according to claim 16, comprising a block having at least one internal conduit to convey a cooling liquid to the tool.

26. A tool holder comprising a rotary tool gripper which projects from the flat front wall and comprises a shaft segment that is provided with two shaft flats and defines an axial direction, a non-rotary part presenting a flat front wall, a forked holding element provided with two fingers, each of which has an inside surface and an outside surface, so that the two respective inside surfaces face each other and each outside surface has an orientation substantially opposite to that of its corresponding inside surface, each finger being suitable to be fitted by its inside surface on one shaft flat, and a locking plate that comprises a recess and is suitable to be fixedly mounted on the flat front wall with the recess facing it, said recess being configured to house the two fingers fitted on the two shaft flats when the locking plate is mounted on the flat front wall, the recess extending across the locking plate and being delimited by two steps against which the two fingers can be fitted by their outside surfaces.

27. The tool holder according to claim 26, wherein the fingers are suitable to fit in the axial direction when they are housed in the recess.

28. The tool holder according to claim 26, wherein the locking plate is a unitary piece that comprises a hole with a diameter greater than the diameter of the tool gripper.

29. The tool holder according to claim 26, wherein the locking plate comprises two pieces configured to be joined around the tool gripper and simultaneously mounted on the flat front wall.

30. The tool holder according to claim 26, comprising a spacer configured to be fixedly mounted on the non-rotary part of the tool holder, the spacer comprising a flat front wall and the locking plate being configured to be mounted on said flat front wall.

31. The tool holder according to claim 26, wherein the locking plate comprises at least one internal conduit to convey a cooling liquid to the tool.

32. The tool holder according to claim 26, wherein the two fingers and the two steps are configured for the outside fitting of the two fingers against the two steps to be looser than the inside fitting of the two fingers on the two shaft flats.

33. A method of using the kit according to claim 1, comprising the following steps to be performed by an operator: with the locking plate mounted on the front wall, fitting the fingers onto the shaft flats, whereby the holding element is made rotatably integral with the tool gripper and the latter is prevented from rotating beyond the positions in which the fingers engage the steps in the recess; using the two hands to dismount the tool from the tool gripper, as the latter is locked for rotation and does not need to be held; using the two hands to mount the same or another tool on the tool gripper; extracting the holding element from the locking plate, thus releasing the tool gripper.

34. The method according to claim 33, comprising the step of, prior to the previous steps, mounting the locking plate on the front wall.

35. The method according to claim 34, comprising the step of, subsequent to the previous steps, dismounting the locking plate from the front wall.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Non-limiting examples of the present disclosure will be described in the following, with reference to the appended drawings, in which:

[0035] FIG. 1 is an exploded view of a rotary tool holder with an example of the present disclosure;

[0036] FIG. 2 is like FIG. 1 but with the different members mounted in place;

[0037] FIG. 3 is an exploded view of a rotary tool holder with another example of the present disclosure;

[0038] FIG. 4 is like FIG. 3 but with the different members mounted in place;

[0039] FIG. 5a is a top view of one side of a locking plate; and

[0040] FIG. 5b is a side view of said locking plate.

DETAILED DESCRIPTION OF EXAMPLES

[0041] FIGS. 1 and 2 show a tool holder 10 for holding a tool (not shown) in a machine tool (not shown). The tool holder 10 is of the rotary type (also called driven tool holder) and comprises a rotary tool gripper 11 and a non-rotary part 16. The non-rotary part 16 comprises a flange 17 to fasten the tool holder to a solid and stationary surface of the machine tool. The flange 17 is of a generally square shape (although the particular shape is not important, what counts is that the flange 17 is wider than the rest of the non-rotary part 16 and projects radially therefrom) and is provided with four perforations 14, one at each corner, to accommodate corresponding bolts 19 and 39 that fixedly fasten the flange 17 to the machine tool. The flange 17 comprises a flat front wall 18 that is facing the rotary tool gripper 11, which projects from said front wall. The rotary tool gripper 11 includes a shaft 15 provided with two diametrically opposed shaft flats, a first flat 12 and a second flat 13, that are located just outside the front wall 18 of the flange 17. The axis of the shaft 15 defines an axial direction.

[0042] A proposed kit for facilitating the change of the tool in the rotary tool gripper 11, and for making it safer, comprises a generally square locking plate 30 and a forked holding element 20. The locking plate 30 comprises two perforations 34 for attachment to the flat front wall 18 by means of two corresponding bolts 39. The two bolts 39 actually fasten both the locking plate and the flange to the aforementioned stationary surface of the machine tool through two of perforations 14 (the other two bolts 19 fasten just the flange to said surface through the other two perforations 14). The locking plate 30 is provided with a central hole 35 that can receive the tool gripper 11, that is, the diameter of the hole 35 is slightly larger than the diameter of the tool gripper 11 in order to allow the locking plate 30 to be carried over the tool gripper 11.

[0043] With further reference to FIGS. 5a and 5b, the locking plate 30 comprises a recess 31 on the side thereof that is to face the flat front wall 18. The recess 31 extends across the plate 30 and defines a first step 32 and a second step 33. The recess 31 has a main direction that is inclined with respect to the square directions of the plate 30, in order to leave space for the two perforations 34 in the two corresponding thick corners 36 of the plate. When the locking plate 30 is mounted on the front wall 18, the recess 31 and the front wall 18 together form a relatively spacious housing for the two shaft flats 12 and 13.

[0044] The holding element 20 is fork-like and comprises a first finger 22 and a second finger 23. The two fingers 22 and 23 are so disposed as to fit onto the two shaft flats 12 and 13, the finger 22 on the flat 12 and the finger 23 on the flat 13, spanner-like. The holding element 20 further comprises a handle 24 provided with a hole 25.

[0045] The housing defined by the recess 31 and the flat front wall 18 is spacious enough to receive the two fingers 22 and 23 fitted by their inside on the two shaft flats 12 and 13 (this spaciousness is manifested in the radial direction but not in the axial direction, since the holding element 20 is to be housed with little looseness in the axial direction). In this disposition, the two fingers 22 and 23 are more or less fitted by their outside on the two steps 32 and 33 of the recess 35, the finger 22 on the step 32 and the finger 23 on the step 33. This fitting is looser than the fitting of the fingers by their inside on the shafts flats 12 and 13. The holding element 20 is also fitted relatively tightly in the axial direction, limited by the flat front wall 18 and the bottom of the recess 31.

[0046] The locking plate 30 can be left mounted on the flat front wall 18 because it does not hinder the normal operation of the tool holder 10. In particular, the locking plate 30 does not by itself interfere with the rotation of the tool gripper 11. When the operator has to change the tool from the tool gripper 11, he/she will insert the fingers 22 and 23 into the recess 31 and onto the shaft flats 12 and 13 (after having properly aligned the shaft). In this disposition, the holding element 20 can rotate only slightly (or very little) before the finger 22 abuts against the step 32 or the finger 23 abuts against the step 33, whereby the rotary tool gripper 11 is effectively locked for rotation by the combined action of the locking plate 30 and the holding element 20. This frees the operator from manually holding the rotary tool gripper 11 and allows him/her to use both hands for expressly changing the tool.

[0047] When the tool has been changed, the operator will extract the holding element from the recess 31 and the rotary tool gripper 11 will be ready to rotate again.

[0048] FIGS. 3 and 4 show a tool holder 10 similar (but no equal) to that of FIGS. 1 and 2, and a kit with the same locking plate 30 and holding element 20 of FIGS. 1 and 2 but with some additional components. The same of like components are given the same reference numeral.

[0049] The flange 17 of FIGS. 3 and 4 does not have a flat front wall but a convex front wall 118. A spacer 40 is intended to be fitted onto the convex front wall 118. The spacer 40 comprises four perforated legs 44 that reach down to the corresponding perforations 14 in the flange 17, and a flat front wall 48 that will cooperate with the recess 31 to form the housing for the fingers 22 and 23 of the holding element 20. This disposition will ensure a properly tight fitting of the holding element 20 in said housing in the axial direction. Of course, the two shaft flats 12 and 13 are located just outside the flat front wall 48 of the spacer 40, and this kit is operated exactly like the kit of FIGS. 1 and 2, just using the flat front wall 48 in place of the flat front wall 18.

[0050] FIGS. 3 and 4 further show a cooling block 50 to refrigerate the tool (not shown). This cooling block does not contribute to the locking of the tool gripper 11 and is only shown to illustrate that the locking plate 30 can be left mounted without hindering the normal operation of the tool. The cooling block 50 comprises an inlet 51 and four outlets 52 oriented toward the tool, so that the pressurized liquid coolant enters the block through the inlet 51 and leaves the block through the outlets 52 and onto the tool. The cooling block 50 could readily be added to the kit of FIGS. 1 and 2.

[0051] Although only a number of examples have been disclosed herein, other alternatives, modifications, uses and/or equivalents thereof are possible. Furthermore, all possible combinations of the described examples are also covered. Thus, the scope of the present disclosure should not be limited by particular examples, but should be determined only by a fair reading of the claims that follow. If reference signs related to drawings are placed in parentheses in a claim, they are solely for attempting to increase the intelligibility of the claim, and shall not be construed as limiting the scope of the claim.