Cutting tool and method for manufacturing a cutting tool

Abstract

A cutting tool, in particular for machining metal, is described. It comprises a tool main body that has at least one interface for receiving a cutting insert that can be attached to the tool main body. At least one cooling duct is provided in the tool main body and has, at its end on the interface side, an outlet section with an elongate outlet cross-section on the interface side. The tool main body is manufactured at least in sections by means of a generative manufacturing process. A method for manufacturing such a cutting tool is also presented.

Claims

1. A cutting tool with a tool main body comprising: at least one interface for receiving a cutting insert for attachment to the tool main body, the cutting insert having at least one cutting edge, wherein at least one cooling duct is provided in the tool main body and the cooling duct comprises, at an end for expelling coolant directly to the cutting insert, an outlet section with a substantially rectangular or arc-shaped outlet cross-section above the interface, wherein the tool main body is manufactured at least in sections by means of an additive manufacturing process, and wherein a length of a side of the rectangular outlet cross-section or an arc length substantially corresponds to a length of the at least one cutting edge.

2. The cutting tool according to claim 1, wherein the cooling duct comprises a supply section that adjoins an end of the outlet section facing away from the interface and has a substantially constant cross-section.

3. The cutting tool according to claim 1, wherein the cutting tool comprises a cutting insert attached to the interface.

4. The cutting tool according to claim 3, wherein the outlet cross-section is substantially directed at a cutting edge of the cutting insert engaging a workpiece.

5. The cutting tool according to claim 1, wherein a cross-section of the cooling duct changes along a cooling duct center axis toward the outlet cross-section.

6. The cutting tool according to claim 3, wherein the cross-section of the outlet section changes substantially only in a dimension transverse to a direction of extent of the cutting edge.

7. The cutting tool according to claim 1, wherein a side of the rectangular outlet cross-section or of the arc-shaped outlet cross-section extends substantially parallelly to the cutting edge, and/or a length of the side of the rectangular outlet cross-section or an arc length substantially corresponds to a length of the cutting edge.

8. The cutting tool according to claim 1, wherein, measured transversely to its longitudinal extent, the outlet cross-section (20) has a maximum width of 2 mm.

9. The cutting tool according to claim 1, wherein the outlet cross-section has a longitudinal extent that corresponds to at least three times a maximum width measured transversely to the longitudinal extent.

10. The cutting tool according to claim 1, wherein the entire tool main body is manufactured by means of an additive manufacturing process.

11. The cutting tool according to claim 1, wherein only a section of the tool main body comprising the outlet section is manufactured by means of an additive manufacturing process.

12. The cutting tool according to claim 1, wherein the cutting tool is a milling, or drilling tool.

13. The cutting tool of claim 4, wherein a normal (N) to the outlet cross-section is substantially directed at the cutting edge of the cutting insert engaging the workpiece.

14. The cutting tool of claim 3, wherein the cross-section of the outlet section continually decreases in a direction toward the cutting insert.

15. The cutting tool of claim 1, wherein the outlet cross-section is positioned in a wall of the tool main body parallel to a flank face of the cutting insert.

16. A cutting tool with a tool main body comprising: at least one interface for receiving a cutting insert for attachment to the tool main body, the cutting insert having at least one cutting edge, wherein at least one cooling duct is provided in the tool main body and the cooling duct comprises, at an end for expelling coolant, an outlet section with an elongate outlet cross-section, the elongate outlet cross-section above the interface and tangential to rotation of the tool main body during a cutting operation, and wherein the tool main body is manufactured at least in sections by means of an additive manufacturing process, and wherein a length of a side of the elongate outlet cross-section substantially corresponds to a length of the at least one cutting edge.

17. The cutting tool according to claim 16, wherein the elongate outlet cross-section is substantially rectangular or arc-shaped.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention is explained below with reference to various exemplary embodiments which are shown in the accompanying drawings. Shown are:

(2) FIG. 1 a cutting tool according to the invention in accordance with a first embodiment manufactured by means of a method according to the present invention,

(3) FIG. 2 the cutting tool of FIG. 1, wherein the cutting inserts are omitted,

(4) FIG. 3 a cutting tool according to the invention in accordance with a second embodiment manufactured by means of a method according to the invention,

(5) FIG. 4 a cutting tool according to the invention in accordance with a third embodiment manufactured by means of a method according to the present invention in a partially transparent illustration,

(6) FIG. 5 a schematic longitudinal section of a cooling duct of a cutting tool according to the invention,

(7) FIG. 6 a schematic longitudinal section of an alternative cooling duct of a cutting tool according to the invention, and

(8) FIG. 7 two schematic variants of an outlet cross-section of a cooling duct shown in FIG. 5 or 6.

DETAILED DESCRIPTION

(9) FIGS. 1 and 2 show a cutting tool 10 that is designed as a milling tool in the embodiment shown.

(10) It comprises a tool main body 12 and a plurality of cutting inserts 14 which each comprise at least one cutting edge 16, and which are designed as indexable inserts in the embodiment shown.

(11) The cutting inserts 14 are each attached to an interface 18 that is formed on the tool main body 12 and that is configured to receive cutting inserts 14.

(12) A cooling duct, of which only an elongate outlet cross-section 20 on the interface side can be seen in FIGS. 1 and 2, is present in the tool main body 12. Said outlet cross-section is substantially directed at the currently active cutting edge 16.

(13) This means that a normal N to the outlet cross-section 20 is substantially directed at the cutting edge 16 (see FIGS. 4, 5, and 6).

(14) The outlet cross-section 20 is slit-shaped, e.g., substantially rectangular. In this case, the sides 20a and 20b of the rectangle are substantially aligned parallelly to the cutting edge 16.

(15) Measured transversely to its longitudinal extent, the outlet cross-section 20 has a maximum width of 2 mm, in particular 1 mm, and a longitudinal extent that corresponds to at least three times, in particular at least five times, the maximum width measured transversely to the longitudinal extent. In the case of an arc-shaped outlet cross-section, the length is measured along the center axis of the arc.

(16) At the same time, a length of the sides 20a, 20b of the rectangle substantially corresponds to a length of the cutting edge 16. In the embodiment shown, the length of the sides 20a, 20b of the rectangle approximately corresponds to 70% of the length of the cutting edge 16.

(17) The embodiment according to FIG. 3 substantially differs from the exemplary embodiment of FIGS. 1 and 2 by the shape of the outlet cross-section 20.

(18) In this case, the outlet cross-section 20 is arc-shaped.

(19) Such an outlet cross-section 20 is preferably used in connection with a cutting insert 14 (not shown further), the cutting edge 16 of which is also arc-shaped. Such a cutting insert 14 is in particular a substantially round indexable insert.

(20) Analogously to the embodiment shown in FIG. 1, the arc-shaped outlet cross-section 20 then substantially extends parallelly to the cutting edge 16.

(21) An arc length of the arc-shaped outlet cross-section 20 furthermore substantially corresponds to a length of the arc-shaped cutting edge 16.

(22) A cooling duct 24 that is composed of an outlet section 26 and a supply section 28 can be seen in the embodiment of the cutting tool 10 shown in FIG. 4 and in FIGS. 5-7.

(23) The outlet section 26 is in this case arranged at an end 24a of the cooling duct 24 on the interface side.

(24) The supply section adjoins an end 26a of the outlet section 26 facing away from the interface 18 and has a substantially constant cross-section.

(25) In the exemplary embodiment of FIG. 4, the cross-section of the supply section 28 is substantially constant and circular.

(26) As can be seen in particular in FIGS. 5 and 6, a cross-section of the outlet section 26 changes along a cooling duct center axis 30.

(27) In the embodiments shown, the cross-section of the outlet section 26 decreases toward the outlet cross-section 20. The outlet section 26 thus forms a nozzle geometry.

(28) The cooling duct center axis 30 in this case is defined as the line that connects the centers of all cross-sections of the cooling duct 24. In the exemplary embodiment of FIG. 6, the cooling duct center axis 30 is therefore kinked.

(29) The cross-section of the outlet section 26 furthermore changes exclusively in a direction that is transverse to a direction of extent of the cutting edge 16. The entire width of the cutting edge is thus supplied with cooling lubricant (see FIG. 7).

(30) The cutting tool 10 can manufactured in all embodiments in accordance with two variants.

(31) Either the tool main body 12 as a whole or only the section 22 of the tool main body 12 comprising the outlet section 26 is manufactured by means of a generative manufacturing process (see in particular the dashed lines in FIGS. 1 through 3).

(32) In the second variant, the other components of the tool main body 12, which can also be called the base part of the tool main body, are, for example, manufactured in a conventional manner.

(33) Such a base part of a tool main body is then provided, and the section 22 comprising the outlet section 26 is manufactured thereon.

(34) In doing so, the supply section 28 of the cooling duct 24 in the main part of the tool main body is produced before the manufacturing of the section 22 of the tool main body 12 comprising the outlet section 26.

(35) In the second variant, the section 22 comprising the outlet section 26 can also alternatively be manufactured separately from the base part of the tool main body. Both parts are subsequently joined, e.g., soldered.

(36) In the embodiments shown, a selective laser melting process is used as the generative manufacturing process.

(37) A steel material, in particular a tool steel, is processed by means of this process.