Drilling tool

Abstract

The invention relates to a drilling tool (1) with a base body (3) having a clamping end (5) and a working end (7) opposite the clamping end (5) in the direction of a longitudinal axis (L), wherein at least one cutting area (9) is arranged on the base body (3) having at least one geometrically defined cutting edge (11), wherein the base body (3) has a circumferential wall (13), wherein a flow channel (15) is arranged in the area of ​​the circumferential wall (13), which extends between the clamping end (5) and the working end (7) at least partially along the longitudinal axis (L) and circumferentially completely along the circumferential wall (13), wherein the flow channel (15) is fluidically connected to a supply channel section (17) arranged at the clamping end (5) for introducing cooling / lubricating medium into the flow channel (15).

Description

[0001] The invention relates to a drilling tool.

[0002] Especially with drilling tools that have a large diameter and / or length, dimensional accuracy can be negatively affected by thermal expansion, either through changes in ambient temperature or, even more significantly, by the heat generated during drilling. The machining process at the cutting edge produces a considerable amount of heat, which is transferred through the cutting edge(s) into the tool body. The larger the drilling tool, the more its dimensional accuracy is affected by the resulting thermal expansion. It is generally known to equip drilling tools with internal cooling channels. However, while this can very effectively cool the cutting area, the heat transferred to the tool body itself can only be dissipated to a limited extent.

[0003] The invention is therefore based on the objective of creating a drilling tool in which the aforementioned disadvantages are at least reduced, and preferably avoided.

[0004] The problem is solved by providing the present technical teaching, in particular the teaching of the independent claims as well as the embodiments disclosed in the dependent claims and the description.

[0005] The problem is solved in particular by creating a drilling tool with a base body, wherein the base body has a clamping end and a working end opposite the clamping end in the direction of a longitudinal axis, wherein at least one cutting area is arranged on the base body, which has at least one geometrically defined cutting edge, wherein the base body has a circumferential wall, wherein a flow channel is arranged in the area of ​​the circumferential wall, which extends between the clamping end and the working end at least partially along the longitudinal axis and in the circumferential direction completely along the circumferential wall, wherein the flow channel is fluidically connected to a supply channel section arranged at the clamping end for introducing cooling / lubricating medium into the flow channel.By extending the flow channel at least partially along the circumferential wall, and particularly along the longitudinal axis and in the circumferential direction, heat can be very effectively dissipated from the base body by the coolant / lubricant flowing within the channel. This is especially true for the radially outer region of the base body—that is, the region of the circumferential wall—where a particularly large amount of heat accumulates and where thermal expansion has a particularly strong effect on dimensional accuracy. The drilling tool proposed here is therefore cooled particularly efficiently and is exceptionally dimensionally accurate due to the appropriately designed flow channel, especially compared to tools where coolant / lubricant channels run primarily in a central, i.e., radially inner, region of the base body or in a straight line along an outer wall.

[0006] The flow channel can be used to cool or temper the base body.

[0007] Optionally, the flow channel is connected to at least one distribution channel for supplying the coolant / lubricant to the at least one cutting area. However, it is also possible for the at least one cutting area to be supplied with coolant / lubricant via an additional, separate channel – optionally from the same, common coolant / lubricant source. If, in such a case, the flow channel is not connected to the distribution channel, it preferably has at least one outlet opening for discharging the coolant / lubricant, which can be arranged, for example, on an end face of the base body, particularly the working end.

[0008] In the context of the present technical teaching, a cooling / lubricating agent is understood to be, in particular, a flowable medium – preferably liquid or gaseous – which is suitable for at least one function selected from cooling and lubrication, wherein the medium is preferably suitable for both functions.

[0009] The circumferential wall is, in particular, a wall closed in the circumferential direction, which preferably extends at least partially between the clamping end and the working end – preferably completely from the clamping end to the working end. In one embodiment, the circumferential wall is cylindrical, in particular circular-cylindrical.

[0010] The drilling tool can therefore be geometrically very simple and inexpensive to manufacture; in particular, it does not have a complicated three-dimensional lattice or truss structure or the like, but rather a homogeneous turning contour, at least in the area of ​​the circumferential wall. Last but not least, this also eliminates or at least significantly reduces the risk of chips removed from a workpiece becoming trapped in the drilling tool.

[0011] Particularly due to the high stability of the circumferential wall, the basic body of the drilling tool can be designed to be compact.

[0012] In one embodiment, the drilling tool is configured for fine drilling. The aforementioned advantages are particularly evident in this application, as exceptionally high dimensional accuracy is required.

[0013] Alternatively or additionally – and especially additionally – the drilling tool is designed for machining large-diameter bores, that is, in particular, bores with a diameter of at least 100 mm, preferably at least 200 mm, preferably at least 300 mm, at least 400 mm, preferably at least 500 mm; preferably at most 800 mm, preferably at most 700 mm, preferably at most 600 mm. With such large diameters, thermal expansion has a particularly detrimental effect on dimensional accuracy, so that, conversely, the advantages already mentioned are realized in a particularly significant way.

[0014] Alternatively or additionally – and particularly additionally – the drilling tool has a large length along its longitudinal axis between the clamping end and the working end, in particular a length of at least 200 mm, preferably at least 300 mm, preferably at least 400 mm; preferably at most 1000 mm, preferably at most 900 mm, preferably at most 800 mm, preferably at most 700 mm, preferably at most 600 mm, preferably at most 500 mm. At such large lengths, thermal expansion has a particularly detrimental effect on dimensional accuracy, so that, conversely, the advantages already mentioned are realized in a particularly significant way.

[0015] Alternatively or additionally – and especially additionally – the drilling tool is designed for machining stator housings for electric motors, particularly drive motors for electric vehicles, and specifically for machining stator bores to accommodate a stator winding. Such bores must be machined with high precision to ensure high efficiency with the lowest possible energy consumption for the respective electric motor; therefore, the aforementioned advantages are particularly evident in this application.

[0016] In one embodiment, the at least one cutting area is arranged in the area of ​​the working end.

[0017] In the context of the present technical teaching, the fact that the flow channel extends completely along the circumferential wall in the circumferential direction means in particular that the flow channel winds around the longitudinal axis at least once - preferably several times - by 360° (in the case of a 360° full circle) in the area of ​​the circumferential wall.

[0018] A longitudinal direction is understood to be an extension in the direction of the longitudinal axis. A radial direction is understood to be a direction perpendicular to the longitudinal axis. A circumferential direction is understood to be a direction that concentrically encompasses the longitudinal axis.

[0019] Preferably, a clamping structure or clamping geometry suitable for clamping in a machine tool or machining center is arranged at the clamping end, or the clamping end itself has such a clamping structure. In one embodiment, the clamping end has a clamping cone as the clamping structure, in particular a hollow shank cone, a steep cone, or a Morse cone. However, the clamping end can also have any other clamping structure or clamping geometry suitable for clamping in a machine tool or machining center.

[0020] According to a further development of the invention, the flow channel is helically shaped. This represents a particularly advantageous embodiment, as the flow channel can wind multiple times around the longitudinal axis while simultaneously extending in the direction of the longitudinal axis due to the pitch of the helix. This allows for particularly efficient heat dissipation from the circumferential wall.

[0021] In one embodiment, the flow channel—particularly in addition to its helical shape in the circumferential wall region—is spirally shaped in the region of the end face of the base body, especially the working end. This allows for very efficient cooling of the base body even in the end face region. In one embodiment, the flow channel in the end face—viewed in the flow direction coming from the supply channel—runs along a spiral from the outside to the inside; alternatively, the flow channel runs along the spiral from the inside to the outside.The at least one distribution channel or the at least one outlet opening can, for example, connect to a channel end of the flow channel - depending on the flow direction along the spiral inside or outside - or the distribution channel or the at least one outlet opening can branch off from the flow channel at any point, but in particular along the spiral inside or outside.

[0022] According to a further development of the invention, the flow channel is formed in the circumferential wall. In this way, the circumferential wall of the base body is cooled particularly efficiently.

[0023] In one embodiment, the flow channel is formed in one piece in the circumferential wall.

[0024] Preferably, the base body with the flow channel formed in the circumferential wall is additively or generatively manufactured in one piece, for example by selective laser melting or selective laser sintering, in particular in a powder bed-based process.

[0025] According to a further development of the invention, it is provided that the circumferential wall surrounds a recess in the base body.

[0026] A preferred insert is arranged in the recess, and the flow channel is positioned between an inner surface of the circumferential wall and an outer surface of the insert. This represents a particularly simple and cost-effective design of the drilling tool, while simultaneously providing the advantages of efficient cooling.

[0027] In one embodiment, the insert component is made of or consists of plastic. Preferably, the insert component is manufactured using an injection molding process.

[0028] In one embodiment, the flow channel is limited by the inner surface of the circumferential wall and the outer surface of the insert part.

[0029] According to a further development of the invention, at least one surface, selected from the inner surface and the outer surface, has a helical channel groove that extends at least partially along the surface in the longitudinal and circumferential directions, and wherein the flow channel is bounded by the channel groove. This represents a particularly simple and efficient design of the drilling tool.

[0030] Preferably, the flow channel is formed by the at least one channel groove.

[0031] In one embodiment, only the inner surface has the helical channel groove by which the flow channel is defined, and in particular formed. In another embodiment, only the outer surface has the helical channel groove by which the flow channel is defined, and in particular formed. In yet another embodiment, both the inner and outer surfaces each have a helical channel groove, wherein the two channel grooves are aligned with each other—or, in other words, overlapping—and together define, and in particular form, the flow channel.

[0032] According to a further development of the invention, the circumferential wall encompasses a recess – in particular the previously mentioned recess – in the base body, wherein at least one deflecting element is arranged in the recess, the deflecting element having a plurality of fins inclined to the longitudinal axis along its circumference, and wherein the flow channel is formed between the fins. The fins distribute the flow of the cooling / lubricant particularly effectively, thereby enabling particularly efficient heat dissipation.

[0033] The deflecting element has the lamellae, particularly radially outward – in the region of an outer circumference. Preferably, it has a solid core on which the lamellae, also referred to as radial lamellae, are arranged radially outward along the circumference.

[0034] In one embodiment, the deflecting element additionally has axial lamellae on at least one end face of the deflecting element, i.e., in particular on an end face of the solid core, which preferably project axially from the end face of the deflecting element. Preferably, these axial lamellae each transition into a radial lamella. Alternatively or additionally, the axial lamellae are each at least partially inclined to an imaginary radius line of the deflecting element and / or curved.

[0035] In one embodiment, the deflecting part including the lamellae comprises a metal or a metal alloy, preferably consisting of the metal or metal alloy.

[0036] In one embodiment, the deflecting part is disk-shaped, meaning that it has, in particular, an extension in the direction of the longitudinal axis that is smaller than its diameter.

[0037] In one embodiment, the lamellae lie with their radially outer ends - particularly close - against the inner surface of the circumferential wall.

[0038] According to a further development of the invention, a plurality of disc-shaped deflection elements are arranged one behind the other in the recess in the direction of the longitudinal axis – essentially in the form of a deflection stack of deflection elements. In this way, deflection of the coolant / lubricant in the recess can be achieved particularly easily.

[0039] In particular, the disc-shaped deflection parts are arranged directly one behind the other in the direction of the longitudinal axis, preferably abutting each other.

[0040] In one embodiment, the radial fins are oriented in opposite directions. In particular, the disc-shaped deflectors are arranged relative to each other such that the fins are oriented in opposite directions. This advantageously achieves multiple deflections of the coolant / lubricant, resulting in particularly efficient heat dissipation.

[0041] Preferably, at least one end-arranged deflecting part of the deflecting stack has axial lamellae at least on a free end face of the deflecting part facing away from the deflecting stack.

[0042] In one embodiment, the two end-arranged deflection parts of the deflection stack each have axial lamellae at least on their free deflection part end face.

[0043] In one embodiment, the disc-shaped deflection parts are preferably identical, and in one embodiment it is possible that deflection parts arranged in the area of ​​the end face of the base body have a larger diameter than deflection parts located further away from the end face.

[0044] In one embodiment, the deflection elements are arranged alternately inverted, that is, in particular, rotated 180° (half a turn) about an axis on which the longitudinal axis is perpendicular (for a full circle of 360°). It is possible that a terminal deflection element located in the region of the end face of the base body is aligned in the same way as a deflection element immediately adjacent to it and located inside the deflection stack.

[0045] In another embodiment, the lamellae are aligned with each other. In particular, the disc-shaped deflectors are arranged relative to each other in such a way that the lamellae are aligned with each other. This results in a particularly simple flow path, while at the same time making the assembly of the drilling tool particularly easy.

[0046] The disc-shaped deflecting elements – optionally with the exception of the larger diameter in the area of ​​the end face of the base body – can preferably be identical in design and arranged in the same way relative to each other. Preferably, they are aligned relative to each other in the circumferential direction such that the individual lamellae are aligned with each other, thus creating a plurality of helical flow channels.

[0047] In yet another embodiment, the inner, disc-shaped deflection elements—and optionally an end-face deflection element—of the deflection stack are identical, except for the larger diameter in the region of the end face of the base body, and are alternately arranged inverted or aligned in the same way. The inner deflection elements preferably have only radial lamellae and no axial lamellae. At least one end deflection element, optionally both end deflection elements, has axial lamellae on its free end face in addition to the radial lamellae.

[0048] Preferably, the radial and optionally axial lamellae are arranged in a uniform distribution along the circumference of the deflection parts, i.e., at equal angular intervals to each other.

[0049] According to a further development of the invention, the base body is designed in multiple parts, comprising a clamping part arranged at the clamping end – and preferably having the clamping structure – and a working part mechanically connected to the clamping part and having the working end, wherein the clamping part has a first material, and the working part has a second material different from the first. Advantageously, this allows the different parts to be optimized independently of one another, and also allows the weight distribution of the drilling tool to be suitably adjusted.

[0050] The working part is preferably connected to the clamping part by a form-fit, material-fit and / or force-fit connection, in particular by screws.

[0051] In one embodiment, the working part itself is designed to be multi-part.

[0052] In one embodiment, the first material has a higher density than the second material. Advantageously, this allows the center of gravity of the drilling tool to be located close to the clamping end, which improves stability and machining accuracy, particularly with regard to tilting loads on the drilling tool.

[0053] In one embodiment, the first material is steel. Alternatively or additionally, the second material is aluminum. In a preferred embodiment, the first material is steel and the second material is aluminum.

[0054] According to a further development of the invention, a knife cassette comprising at least one geometrically defined cutting edge is arranged in the at least one cutting area, wherein the knife cassette is supported on at least one contact surface in the longitudinal axis and circumferential direction. Advantageously, this allows for both precise installation and easy replacement of the at least one geometrically defined cutting edge.

[0055] The at least one geometrically defined cutting edge can be formed as a single piece on the knife cassette or permanently attached to the knife cassette, for example by hard soldering, or a cutting plate or knife plate can be arranged in the knife cassette, which in turn has the at least one geometrically defined cutting edge – either as a single piece or permanently attached, for example by hard soldering. The cutting plate or knife plate is, in particular, rigidly but replaceably attached to the knife cassette.

[0056] Preferably, the at least one cutting edge is adjustable, in particular by adjusting a position of the knife cassette and / or by adjusting a position of the cutting or knife plate on the knife cassette.

[0057] In one embodiment, the drilling tool also has at least one guide rail, in particular in the form of a guide insert placed in a guide cassette. The at least one guide rail can be designed to be modularly replaceable.

[0058] The invention will be explained in more detail below with reference to the drawing. The drawing shows: Fig. 1 a representation of a first embodiment of a drilling tool; Fig. 2 a representation of a second embodiment of a drilling tool; Fig. 3 a detailed representation of a third embodiment of a drilling tool, and Fig. 4 a representation of a fourth embodiment of a drilling tool.

[0059] Fig. Figure 1 shows a representation of a first embodiment of a drilling tool 1.

[0060] The drilling tool 1 has a base body 3, which has a clamping end 5 and a working end 7 opposite the clamping end 5 in the direction of a longitudinal axis L. At least one cutting area 9 – preferably located in the region of the working end 7 – is arranged on the base body 3, and this cutting area has at least one geometrically defined cutting edge 11. The base body 3 also has a circumferential wall 13, in the region of which a flow channel 15 is arranged. This flow channel extends at least partially along the longitudinal axis L between the clamping end 5 and the working end 7, and completely along the circumferential wall 13. The flow channel 15 is fluidically connected to a supply channel section 17 arranged at the clamping end 5 for introducing coolant / lubricant into the flow channel 15.Optionally, the flow channel 15 is also fluidically connected to at least one distribution channel (not shown) for supplying the coolant / lubricant to the at least one cutting area 9. The coolant / lubricant flowing in the flow channel 15 allows heat to be very effectively dissipated from the base body 3, particularly from the radially outer region of the base body 3, thus ensuring high dimensional accuracy of the drilling tool 1.

[0061] The drilling tool 1 is particularly designed for fine boring, preferably for machining large-diameter bores, that is, in particular with a diameter – that is, a cutting circle of the at least one cutting edge 11 – of at least 100 mm, preferably at least 200 mm, preferably at least 300 mm, at least 400 mm, preferably at least 500 mm; preferably at most 800 mm, preferably at most 700 mm, preferably at most 600 mm. Alternatively or additionally – and in particular additionally – the drilling tool 1 has a long length, measured along the longitudinal axis L, between the clamping end 5 and the working end 7, in particular a length of at least 200 mm, preferably at least 300 mm, preferably at least 400 mm; preferably at most 1000 mm, preferably at most 900 mm, preferably at most 800 mm, preferably at most 700 mm, preferably at most 600 mm, preferably at most 500 mm. The drilling tool 1 can – as in Fig. Figure 4 shows further, additional cutting edges with different flight paths. The diameters specified above refer in particular to the largest flight circle of the drilling tool 1.

[0062] Preferably, the drilling tool 1 is designed for machining stator housings for electric motors, in particular drive motors for electric vehicles, especially for machining stator bores for receiving a stator winding.

[0063] In the first embodiment, the flow channel 15 is helically shaped. Additionally, it is spirally shaped in the region of an end face 19 of the working end 7. The at least one distribution channel can, for example, connect to a channel end of the flow channel 15, or it can branch off from the flow channel 15 at any point.

[0064] In the first embodiment, the flow channel 15 is formed in one piece in the circumferential wall 13. Preferably, the base body 3 with the flow channel 15 is additively or generatively manufactured in one piece.

[0065] In the illustrated first embodiment - and preferably also in the other embodiments - a knife cassette 37 having at least one geometrically defined cutting edge 11 - not shown here - is arranged in the at least one cutting area 9, wherein the knife cassette 37 is preferably mounted on a contact surface in the direction of the longitudinal axis L and in the circumferential direction.

[0066] The at least one geometrically defined cutting edge 11 is preferably formed on a knife plate 42, which in turn is rigidly but interchangeably clamped in the knife cassette 37.

[0067] It is also shown that the drilling tool 1 can have guide rails, in particular in the form of guide inserts 46 inserted in guide cassettes 44.

[0068] Fig. Figure 2 shows a representation of a second embodiment of the drilling tool 1.

[0069] For clarity, elements depicted multiple times in a figure are each marked with a reference symbol only once. Furthermore, identical and functionally equivalent elements in all figures are marked with the same reference symbol, thus referring back to the preceding description.

[0070] In this second embodiment, the circumferential wall 13 encompasses a recess 21 in the base body 3, which is open, in particular, from the end face 19. An insert 23 is arranged in the recess 21, and the flow channel 15 is arranged between an inner surface 25 of the circumferential wall 13 and an outer surface 27 of the insert 23. Specifically, the insert 23 is inserted into the recess 21 from the end face 19. The recess 21 is preferably closed, either by the insert 23 itself or by another part, in particular a cover.

[0071] In a), the drilling tool 1 is shown with the insert 23 inserted into the recess 21. In b), the insert 23 is shown alone.

[0072] The insert part 23 preferably comprises or consists of plastic; it may be manufactured using an injection molding process.

[0073] In the second embodiment, the outer surface 27 of the insert part 23 has a helical channel groove 29 which extends at least partially along the outer surface 27 in the direction of the longitudinal axis L and in the circumferential direction. The flow channel 15, which is also at least partially helical, is bounded or formed by the channel groove 29.

[0074] Fig. Figure 3 shows a detailed representation of a third embodiment of the drilling tool 1.

[0075] In this third embodiment, a deflection stack 30 with a plurality of deflection elements 31 is arranged in the recess 21 (not shown here), wherein the deflection elements 31 each have a plurality of radial lamellae 33 inclined at an angle to the longitudinal axis L along their circumference. The flow channel 15 is formed between the radial lamellae 33.

[0076] A deflecting element 31' located at the end of the deflecting stack 30 additionally has axial lamellae 33' on a deflecting element end face 34 facing away from the deflecting stack 30. These lamellae project axially from the deflecting element end face. Each axial lamella 33' transitions into a radial lamella 33. In particular, the axial lamellae 33' are each at least partially inclined to an imaginary radius line of the terminal deflecting element 31' and are curved.

[0077] In a), the deflection stack 30 to be inserted or usable in the recess 21 is shown.

[0078] The lamellae 33 preferably lie with their radially outer ends - especially close - against the inner surface 25.

[0079] The internal deflection parts 31, which are preferably identical to each other, are preferably arranged directly one behind the other along the longitudinal axis L, in a position abutting each other.

[0080] In this third embodiment shown here, the lamellae 33 of immediately adjacent inner deflection parts 31 are oriented in opposite directions to each other, in particular such that the lamellae 33 are oriented in opposite directions to each other. For this purpose, the identically designed deflection parts 31 are arranged alternately inverted – that is, rotated 180° about an axis that is perpendicular to the longitudinal axis L (for a full circle encompassing 360°). The end deflection part 31', however, is oriented in the same way as the inner deflection part 31 immediately adjacent to it.

[0081] Furthermore, the deflection parts 31, 31' arranged in the area of ​​the end face 19 when inserted into the recess 21 have a larger diameter than the deflection parts 31 that are further away from the end face 19.

[0082] In b), one deflection part 31 - here disc-shaped - is shown in isolation from the majority of internal deflection parts 31.

[0083] The deflecting element 31 has the lamellae 33 radially outward – in the region of its outer circumference. Preferably, it has a solid core 35 on which the lamellae 33 are arranged radially outward along the circumference. This deflecting element 31 has no axial lamellae.

[0084] Figure c) shows the terminal deflecting part 31', which additionally has the axial lamellae 33' on the deflecting part end face 34.

[0085] In particular, the lamellae 33, 33' are arranged uniformly along the circumference of the deflection parts 31, 31', i.e. at equal angular distances to each other.

[0086] Generally, in Fig. For the sake of simplicity, fewer lamellae 33, 33' are shown in Figure 3 than the terminal deflection parts 31, 31' preferably have. Preferably, the deflection parts 31, 31' have two, three, or four times more lamellae 33, 33' than shown, or an even greater number of lamellae 33, 33'.

[0087] Fig. Figure 4 shows a representation of a fourth embodiment of the drilling tool 1.

[0088] In the fourth embodiment – ​​and preferably also in the other embodiments – the base body 3 is preferably designed in multiple parts, comprising a clamping part 47 arranged at the clamping end 5 and having a clamping structure 44, here a clamping cone 45, and a working part 49 mechanically connected to the clamping part 47 and having the working end 7, wherein the clamping part 47 comprises a first material, and the working part 49 comprises a second material different from the first. The working part 49 is preferably positively locked, material-locked, and / or force-locked to the clamping part 47, in particular by screws. The working part 49 can itself be designed in multiple parts, for example, with the knife cassette 37.

[0089] The clamping cone 45 can be designed, for example, as a hollow shaft cone, steep cone or Morse cone.

[0090] Preferably, the first material has a higher density than the second material. This places the center of gravity of the drilling tool 1 close to the clamping end 5, resulting in particularly high stability and machining accuracy, especially with regard to tilting loads.

[0091] The first material can be steel, and the second material aluminum.

Claims

[1] Drilling tool (1) with a base body (3) having a clamping end (5) and a working end (7) opposite the clamping end (5) in the direction of a longitudinal axis (L), wherein at least one cutting area (9) is arranged on the base body (3) having at least one geometrically defined cutting edge (11), wherein the base body (3) has a circumferential wall (13), wherein a flow channel (15) is arranged in the area of ​​the circumferential wall (13), which extends between the clamping end (5) and the working end (7) at least partially along the longitudinal axis (L) and circumferentially completely along the circumferential wall (13), wherein the flow channel (15) is fluidically connected to a supply channel section (17) arranged at the clamping end (5) for introducing cooling / lubricating medium into the flow channel (15). [2] Drilling tool (1) according to claim 1, wherein the flow channel (15) is helically shaped. [3] Drilling tool (1) according to one of the preceding claims, wherein the flow channel (15) is formed in the circumferential wall (13) in particular in one piece. [4] Drilling tool (1) according to one of claims 1 or 2, wherein the circumferential wall (13) encompasses a recess (21) in the base body (3), wherein an insert part (23) is arranged in the recess (21), and wherein the flow channel (15) is arranged between an inner surface (25) of the circumferential wall (13) and an outer surface (27) of the insert part (23), in particular being limited by the inner surface (25) of the circumferential wall (13) and the outer surface (27) of the insert part (23). [5] Drilling tool (1) according to claim 4, wherein at least one surface, selected from the inner surface (25) and the outer surface (27), has a helical channel groove (29) which extends at least partially along the surface in the longitudinal direction and in the circumferential direction, and wherein the flow channel (15) is bounded by the channel groove (29). [6] Drilling tool (1) according to claim 1, wherein the circumferential wall (13) encompasses a recess (21) in the base body (3), wherein at least one deflecting part (31) is arranged in the recess (21) which has a plurality of lamellae (33) inclined to the longitudinal axis (L) along its circumference, and wherein the flow channel (15) is formed between the lamellae (33). [7] Drilling tool (1) according to claim 6, wherein a plurality of disc-shaped deflecting parts (31) are arranged one behind the other in the recess in the direction of the longitudinal axis (L), the lamellae (33) of which are preferably oriented opposite to each other or in the same direction to each other. [8] Drilling tool (1) according to one of the preceding claims, wherein the base body (3) is formed in multiple parts, with a clamping part (47) arranged at the clamping end (5) and a working part (49) mechanically connected to the clamping part (47) and having the working end (7), wherein the clamping part (47) has a first material, wherein the working part (49) has a second material different from the first material, wherein preferably the first material has a higher density than the second material. [9] Drilling tool (1) according to one of the preceding claims, wherein a knife cassette (37) having at least one geometrically defined cutting edge (11) is arranged in the at least one cutting area (9), wherein the knife cassette (37) is supported in the direction of the longitudinal axis (L) and in the circumferential direction on at least one contact surface.

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