TURNING TOOL

Abstract

A turning tool includes a tool body having an insert seat to accommodate a cutting insert and a mounting means for mounting the cutting insert at the tool body. A guiding block is movably mounted between a first position and a second position at the tool body. A fluid passage with an inlet end and at least one outlet is arranged to eject a jet of a cooling fluid from the inlet end to the at least one outlet onto a clearance surface associated with the cutting edge at the cutting insert. When the guiding block is in the first position the jet of cooling fluid is ejected along a first line and when the guiding block is in the second position the jet of cooling fluid is ejected along a second line, wherein the first line and the second line have different orientations and intersect each other at a position in a downstream direction from the outlet.

Claims

1. A turning tool comprising: a tool body having an insert seat arranged for accommodating a cutting insert, which has a cutting edge and a therewith associated clearance surface; a guiding block movably mounted at the tool body between a first position and a second position; and a fluid passage with an inlet end and at least one outlet which is arranged to guide a cooling fluid from the inlet end to the at least one outlet of the fluid passage, wherein the at least one outlet is arranged to eject a jet of the cooling fluid towards an area where the clearance surface is located when the cutting insert is accommodated on the insert seat, wherein a first section of the fluid passage extends through the tool body, wherein a second section of the fluid passage extends through the guiding block, and wherein at least one outlet forms an end of the second section of the fluid passage in the guiding block, at least the tool body or the guiding block being arranged such that when the guiding block is in the first position the jet of cooling fluid is ejected along a first line and such that when the guiding block is in the second position the jet of cooling fluid is ejected along a second line, wherein the first line and the second line have different orientations and intersect each other at a position in a downstream direction from the outlet.

2. The turning tool according to claim 1, wherein the guiding block is pivotably mounted at the tool body.

3. The turning tool according to claim 1, further comprising a transfer element arranged to transfer the cooling fluid from the first section of the fluid passage in the tool body to the second section of the fluid passage in the guiding block.

4. The turning tool according to claim 3, wherein the transfer element extends from an outer surface of the tool body into a hole in the guiding block, the transfer element including a cylindrical outer surface in engagement with an inner cylindrical surface of the hole in the guiding block, wherein the transfer element includes an inner axial fluid duct in fluid communication with the first section of the fluid passage.

5. The turning tool according to claim 1, wherein a third section of the fluid passage extends through the guiding block, wherein a first outlet forms an end of the second section of the fluid passage in the guiding block, and wherein a second outlet forms an end of the third section of the fluid passage in the guiding block.

6. The turning tool according to the claim 5, wherein the first outlet is located in a first outer surface section of the guiding block and wherein the second outlet is located in a second outer surface section of the guiding block, wherein a direction of a surface normal of the first outer surface section is different from a direction of a surface normal of the second outer surface section.

7. The turning tool according to claim 3, wherein the transfer element is arranged to selectively transfer the cooling fluid either from the first section of the fluid passage in the tool body to the second section of the fluid passage in the guiding block or from the first section of the fluid passage in the tool body to a third section of the fluid passage, wherein a second outlet forms an end of the third section of the fluid passage.

8. The turning tool according to claim 4, wherein either the transfer element includes a circumferentially extending second groove in the cylindrical outer surface or the guiding block includes a circumferentially extending second groove in the inner cylindrical surface, wherein the second groove is located at a second axial position, wherein the transfer element includes a second radial fluid duct connecting the inner axial fluid duct and the second groove, and wherein the third section of the fluid passage in the guiding block discharges into the cylindrical hole at the second axial position.

9. The turning tool according to claim 8, wherein the first groove and the second groove each have a circumferential extension of less than 360°, and wherein the first groove and the second groove are arranged such that at least when the guiding block is in the first position the second section of the fluid passage is in fluid communication with the first section of the fluid passage and the third section of the fluid passage is not in fluid communication with the first section of the fluid passage and such that at least when the guiding block is in the second position the third section of the fluid passage is in fluid communication with the first section of the fluid passage and the second section of the fluid passage is not in fluid communication with the first section of the fluid passage.

10. The turning tool according to claim 1, wherein in the first position of the guiding block an abutment surface of the guiding block is in engagement with a first stop surface of the tool body, and wherein in the second position of the guiding block an abutment surface of the guiding block is in engagement with a second stop surface of the tool body.

11. The turning tool according to claim 1, wherein the insert seat has a bottom support surface with a surface normal, and wherein the at least one outlet in the guiding block is distanced from the bottom support surface in a direction opposite to a direction of the surface normal of the bottom support surface.

12. The turning tool according to claim 1, wherein the turning tool in addition to the fluid passage for cooling the clearance surface includes a cooling duct for ejection of a cooling fluid onto an area where a chip surface associated with the cutting edge is located when the cutting insert is accommodated on the insert seat.

13. The turning tool according to claim 1, further comprising the cutting insert and a mounting means, wherein the cutting insert is accommodated on the insert seat and fastened by the mounting means.

14. The turning tool according to claim 1, wherein the turning tool is located in an imaginary circle having a diameter equal to a minimum diameter of an inner surface turnable by the turning tool, wherein the circle is in engagement with the cutting edge, and wherein in the first position the guiding block protrudes beyond the circle and in the second position the guiding block is distanced from the circle without intersecting the circle.

15. The turning tool according to the claim 1, wherein the first line and the second line intersect each other at a position on the clearance surface.

16. The turning tool of claim 4, wherein the transfer element includes a circumferentially extending first groove in the cylindrical outer surface.

17. The turning tool of claim 4, wherein the guiding block includes a circumferentially extending first groove in the inner cylindrical surface, wherein the first groove is located at a first axial position.

18. The turning tool of claim 17, wherein the transfer element includes a first radial fluid duct connecting the inner axial fluid duct and the first groove.

19. The turning tool of claim 17, wherein the second section of the fluid passage in the guiding block discharges into the cylindrical hole at the first axial position.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0043] Further advantages, features and applications of the present disclosure will become apparent from the following description of embodiments and the corresponding figures attached. The foregoing as well as the following detailed description of implementations of the present disclosure will be better understood when read in conjunction with the appended drawings. It should be understood that the implementations depicted are not limited to the precise arrangements and instrumentalities shown.

[0044] FIG. 1 is a broken away isometric view of an implementation of a turning tool according to the present disclosure with the guiding block in the first position.

[0045] FIG. 2 is a front view of the turning tool of FIG. 1 with the guiding tool in the first position.

[0046] FIG. 3 is a broken away isometric view of the turning tool of FIGS. 1 and 2 with the guiding block in the second position.

[0047] FIG. 4 is a front view of the turning tool of FIGS. 1 to 3 during turning of an inner surface of a workpiece with the guiding block in the second position.

[0048] FIG. 5 is an isometric view of the guiding block and a transfer element of the turning tool of FIGS. 1 to 4 from a first perspective.

[0049] FIG. 6 is an isometric view of the guiding block and transfer element of FIG. 5 from a second perspective.

DETAILED DESCRIPTION

[0050] In the figures, identical elements are denoted by identical reference numbers.

[0051] FIGS. 1 to 6 show an implementation of a turning tool 1 according to the present disclosure. The turning tool 1 allows an optimized cooling of a cutting insert 2 during external turning as well as during internal turning. The basic body of the turning tool 1 is formed by the tool body 4 carrying the insert seat 3 to accommodate the cutting insert 2. In order to mount the cutting insert 2 in the insert seat 3 of the tool body 4, the turning tool 1 further has a clamp 5 which is screwed onto the tool body 4 by a mounting screw 6 reaching through a hole in the clamp 5 and engaging into a threaded hole in the tool body 4. In addition to the actual clamping functionality the clamp 5 comprises a cooling duct having two outlets 7a, 7b to eject a jet of cooling fluid from the clamp 5 onto the chip surface 8 of the cutting insert 2.

[0052] The cutting insert 2 in the implementation shown has a rhombic basic area with a rhombic top surface 8, a rhombic bottom surface in engagement with a bottom supporting surface of the insert seat 3 as well as four side surfaces 9, 10. Cutting edges 11, 12 are formed where the side surfaces 9, 10 intersect with the top surface 8 of the cutting insert 2.

[0053] In the present implementation, the cutting insert is mounted in order to provide the cutting operation predominantly by the cutting corner formed where the two cutting edges 11, 12 intersect.

[0054] In order to enhance the cooling of the cutting insert 2 in addition to the cooling ducts in the clamp 5 an efficient cooling of the clearance surface formed by the side surfaces 9, 10 of the cutting insert 2 is provided. As the major part of the cutting performance is carried out by the cutting corner 13 of the cutting insert 2 a most efficient cooling on the clearance surface is provided if a jet of cooling fluid 14 during the cutting operation streaks along the edge connecting the two side surfaces 9, 10 and being associated with the cutting corner 13.

[0055] In order to provide a jet 14 of cooling fluid which streaks along the clearance surface associated with the cutting corner 13 the jet 14 of cooling liquid is ejected from a nozzle at a position directly below the cutting corner 13 as it is depicted in FIGS. 1 and 2.

[0056] The turning tool 1 has a guiding block 15 which is pivotably mounted on the tool body 4 around a pivoting axis which is defined by a screw 16. The position of the guiding block 15 depicted in FIGS. 1 and 2 is denoted the first position in the sense of the present disclosure and the position of the guiding block 15 depicted in FIGS. 3 and 4 is denoted the second position in the sense of the present disclosure.

[0057] While providing an optimized geometry for the jet 14 of cooling fluid towards the side surface 9, 10, it is readily apparent in particular from FIGS. 2 and 4 that the guiding block 15 when it is in the first position would interfere with the material of a workpiece when using the turning tool 1 for internal turning. The situation occurring during internal turning is depicted in FIG. 4. While FIG. 4 shows a front view of the turning tool 1 the turning tool 1 is depicted in an isometric view from above in FIG. 2.

[0058] In the second position the guiding block 15 is located within and distanced from an imaginary circle which is in engagement with the active cutting corner of a cutting insert 2 and which defines the minimum radius an inner surface may have for internal turning with the turning tool 1 according to the present disclosure. This situation is depicted in FIG. 4, wherein the imaginary circle is provided an inner surface 18 of a tubular workpiece 17 to be internally turned. Due to the pivoting of the guiding block 15 into the second position the guiding block 15 does not interfere with the tubular workpiece 17 and internal turning of the inner surface 18 of the tubular workpiece 17 can be performed.

[0059] Still, the guiding block 15 provides an efficient cooling of the clearance surface 9, 10 although the jet 14 of cooling liquid no longer streaks along the entire clearance surface connecting the upper cutting corner and the lower surface of the cutting insert 2.

[0060] By a comparison of FIGS. 1 and 2 on the one hand and FIGS. 3 and 4 on the other hand the general concept of the present disclosure can be explained. For an efficient cooling of the clearance surface formed by the side surfaces 9, 10 the jet of cooling liquid 14 must hit the side surfaces 9, 10 in either position of the guiding block 15. However, this implies that the jet of cooling liquid 14 has different orientations in the first and second positon of the guiding block 15. When the guiding block 15 is in its first position as depicted in FIGS. 1 and 2 the jet of cooling liquid 14 is described by a first line. When the guiding block 15 is in its second position as depicted in FIGS. 3 and 4 the jet of cooling liquid 14 is described by a second line. The first and second lines have different starting points depending on the position of the guiding block 15, but intersect on the side surfaces 9, 10 of the cutting insert 2 downstream from the respective outlets 19, 20 in the guiding block 15.

[0061] While FIGS. 1 to 4 provide an understanding of the general concept of the present disclosure FIGS. 5 and 6 reveal the details of the design of the guiding block 15 in order to provide the optimized jet 14 of cooling liquid.

[0062] In the implementation depicted in FIGS. 1 to 6 the guiding block 15 carries two outlets, namely a first outlet 19 and a second outlet 20 which eject the jet 14 of cooling liquid in the first position and in the second position, respectively. The fluid passage 21 is formed by multiple sections, wherein a first section (not depicted in the figures) extends in the tool body 4 and wherein a second section 22 and a third section 23 extend in the guiding block 15.

[0063] The screw 16 forming the pivot axis for the guiding block 15 also forms the transfer element in the sense of the present disclosure. This transfer element 16 not only provides a transfer of the cooling liquid from the first section of the fluid passage in the tool body 4 to the second and third sections 22, 23 of the fluid passage but also allows to switch the transfer alternately to either of the two sections 22, 23.

[0064] The transfer element 16 has a hollow cylindrical part, wherein the cooling liquid can flow through the duct 24 extending in an axial direction of the screw 16 in the element. The screw 16 is screwed with its rear end 25 into a hole in the tool body 4. The hole in the tool body 4 concentrically surrounds an end of the first section of the fluid passage in the tool body 4. Thus, the cooling liquid flowing through the first section of the fluid passage is then further guided by the axial fluid duct 24 in the transfer element.

[0065] The transfer element 16 further has a switching element 28 extending in a hole 26 in the guiding block 15. An inner cylindrical surface 27 of the hole 26 is in engagement with an outer cylindrical surface 29 of the switching element 28. During operation of the turning tool 1 the switching element 28 of the transfer element 16 is stationary with respect to the tool body 4. I.e. when pivoting the guiding block 15 the guiding block 15 not only pivots with respect to the tool body 4, but also with respect to the switching element 28 of the transfer element 16. The switching element 28 of the transfer element 16 has a radial fluid duct 30, 31 at two axial positions guiding the cooling fluid in a radial direction of the transfer element 28.

[0066] The first radial fluid duct 30 connects the axial fluid duct 24 at a first axial position to a first groove 32 in the surface 29 of the switching element 28. The first axial position of the first groove 32 is identical to the axial position of a rear end 33 of the second section 22 of the fluid passage. The first groove 32 extends in a circumferential direction in the cylindrical surface 29 of the switching element 28. However, the first groove 32 does not extend over 360° of the switching element 28, but only covers a certain angle. Consequently, a flow of cooling liquid from the inner axial fluid duct 24 through the first radial fluid duct 30 into the first groove 32 and further into the second section 22 of the fluid passage only occurs when the guiding block 15 is in the first position or close to the first position.

[0067] The same principle also applies with respect to the second axial position defined by the second radial fluid duct 31 which also ends in a second circumferentially extending groove 34 in the cylindrical surface 29 of the switching element 28. As the rear end 35 of the third section 23 of the fluid passage in the guiding block 15 is at the same axial position as the second groove 34 a flow of cooling liquid from the inner axial fluid duct 24 through the second radial fluid duct 31 and the second groove 34 into the third section 23 of the fluid passage in the guiding block 15 only occurs when the guiding block 15 is in the second position.

[0068] By the design of the transfer element 16 as well as the guiding block 15 a pivoting of the guiding block 15 around the screw 16 not only changes the position of the outlets 19, 20 of the second section 22 and third section 23 of the fluid passage, respectively, but also switches such that cooling liquid in the first position of the guiding block 15 as it is depicted in FIGS. 1 and 2 is only ejected through the first outlet 19 in the guiding block 15 and such that when the guiding block 15 is in its second position as it is depicted in FIGS. 3 and 4 cooling liquid is only ejected from the second outlet 20.

[0069] Thus, the design as it is shown in the figures allows to change the direction of the jet 14 of cooling liquid while still avoiding an unnecessary leakage of cooling liquid through the other outlet which is not in the correct position during operation.

[0070] From FIGS. 5 and 6 it is clearly derivable that the design and shape of the second section 22 and third section 23 of the cooling duct in the guiding block 15 has been chosen in order to provide an optimized direction of the jet 14 of cooling liquid in the first position of the guiding block 15 but also in the second position of the guiding block 15.

[0071] For the purposes of original disclosure, it is noted that all features become apparent for a person skilled in the art from the present description, the figures and the claims even if they have only been described with reference to particular further features and can be combined either on their own or in arbitrary combinations with other features or groups of features disclosed herein as far as such combinations are not explicitly excluded or technical facts exclude such combinations or make them useless. An extensive, explicit description of each possible combination of features has only been omitted in order to provide a short and readable description.

[0072] While the disclosure has been shown in detail in the figures and the above description, this description is only an example and is not considered to restrict the scope of protection as it is defined by the claims. The disclosure is not restricted to the disclosed embodiments.

[0073] Modifications to the disclosed embodiments are apparent for a person skilled in the art from the drawings, the description and the attached claims. In the claims, the word “comprising” does not exclude other elements or steps and the undefined article “a” does not exclude a plurality. The mere fact that some features have been claimed in different claims does not exclude their combination. Reference numbers in the claims are not considered to restrict the scope of protection.

REFERENCE NUMBERS

[0074] 1 turning tool [0075] 2 cutting insert [0076] 3 insert seat [0077] 4 tool body [0078] 5 clamp [0079] 6 mounting screw [0080] 7a, 7b outlet of the cooling duct for cooling the chip surface [0081] 8 top surface [0082] 9, 10 side surface [0083] 11, 12 cutting edge [0084] 13 cutting corner [0085] 14 jet of cooling liquid [0086] 15 guiding block [0087] 16 screw forming the transfer element [0088] 17 tubular workpiece [0089] 18 inner surface of the tubular workpiece 17 [0090] 19 first outlet [0091] 20 second outlet [0092] 21 fluid passage [0093] 22 second section of the fluid passage [0094] 23 third section of the fluid passage [0095] 24 axial fluid duct [0096] 25 rear end of the screw [0097] 26 hole in the guiding block 15 [0098] 27 inner cylindrical surface of the hole 26 [0099] 28 switching element [0100] 29 outer cylindrical surface of the switching element 28 [0101] 30 first radial fluid duct [0102] 31 second radial fluid duct [0103] 32 first circumferentially extending groove [0104] 33 rear end of the second section 22 of the fluid passage [0105] 34 second circumferentially extending groove [0106] 35 rear end of the third section 23 of the fluid passage