Drilling and countersinking cutter device

Abstract

The invention relates to a drilling and counter-boring tool arrangement having a drilling tool (9) and a counter-boring sleeve (11), the drilling tool (9) having a clamping shank (13) and a drill body (15) connected thereto, at least one drill-shaped rib (17) extending along a rotational axis (R) of the drill body to a drill tip. The drilling tool (9) passes through a counter-boring sleeve (11) which has a counter-boring sleeve blade (37) on its end face facing the drill tip. And the countersinking sleeve blade moves backwards by an axial distance (delta a) from the drill tip. During the drilling process, a drilling tool (9) can be introduced into the workpiece (1) by a drilling stroke to create a workpiece hole (5). In the subsequent process of the drilling process, the counter sinking sleeve (11) is in cutting joint with the opening edge area of the workpiece hole (5) through the counter sinking sleeve cutting edge (37) of the counter sinking sleeve (11).

Description

Technical Field

[0001] The invention relates to a countersinking tool device according to the preamble of claim 1 , a drilling tool according to the preamble of claim 9 , and a countersinking sleeve according to the preamble of claim 10 . Background Art

[0002] Such countersinking tool devices are used, for example, in vehicle construction for the production of cylinder head bores and for flattening the opening edge region of the cylinder head bore, which opening edge region should possibly fulfill a sealing function.

[0003] In a process for machining such a workpiece, pre-milling is first performed in a first process step, in which a first milling tool pre-mills the workpiece surface to be machined with an excess. Subsequently, in a second process step, finish milling is performed, in which the excess of the workpiece surface to be machined is milled off. In a subsequent third process step, a drilling tool is inserted into the solid material of the workpiece on the machined flat workpiece surface to produce a workpiece hole.

[0004] In order to reduce the complexity of manufacturing technology and process complexity when machining a workpiece, a drilling and countersinking tool device of this type is provided. The drilling and countersinking tool device has a drilling tool, which has a clamping shank and a drill body connected to the clamping shank. At least one drill-shaped rib with a supporting chamfer extends along the rotation axis of the drill body to the drill tip. The drilling tool is guided through a countersinking sleeve, which has a countersinking sleeve blade on its end side facing the drill tip. The countersinking sleeve blade is axially moved back from the drill tip. The following machining process can be performed by this tool combination: that is, the drilling tool is inserted into the workpiece with a drilling stroke to produce a workpiece hole. At the end of the drilling stroke, the countersinking sleeve uses its countersinking sleeve blade to cut and engage with the opening edge area of ​​the workpiece hole, thereby flattening the opening edge area of ​​the workpiece hole.

[0005] In such devices, there is also the problem that if the countersinking sleeve and the drilling tool are designed as separate components, an annular gap must be formed between the two components. At the end of the drilling stroke, if the countersinking sleeve cutting edge contacts the surface edge region of the workpiece, a material nub or material accumulation can form in this annular gap, which can lead to premature breakage of the tool.

[0006] DE 10 2019 203 531 A1 discloses a drilling / chamfering tool having a drill head with a clamping sleeve extending in the longitudinal direction, which is designed to accommodate and fix the drill head in a variable length. US 2005 / 0047882 A1 discloses a tool having a drill head and a countersink drill fastened to the drill head. The drill head has a protruding profile rib and at least one chip flute. The countersink drill comprises a plurality of adjustable inserts. Summary of the invention

[0007] The object of the present invention is to provide a countersinking tool device in which a more process-reliable machining of workpieces is possible compared to the prior art.

[0008] This object is achieved by the features of claim 1, 9 or 10. Preferred developments of the invention are disclosed in the dependent claims.

[0009] The invention is based on a drilling countersinking tool device, which has a drilling tool and a countersinking sleeve. The drilling tool is configured as a drill body having a clamping shank and connected to the clamping shank, and at least one drill-shaped rib having at least one supporting chamfer extends along the rotation axis of the drill body to the drill tip. The drilling tool passes through the countersinking sleeve. The countersinking sleeve has a countersinking sleeve blade on its end side facing the drill tip, which extends in particular transversely to the rotation axis. The countersinking sleeve blade is set back from the drill tip by an axial distance. Thus, the drilling process is carried out as follows: First, the drilling tool is inserted into the solid material of the workpiece to the theoretical hole depth with a drilling stroke to produce a workpiece hole. In the subsequent progress of the drilling process, for example at the end of the drilling stroke, the countersinking sleeve uses its countersinking sleeve blade to cut the opening edge area of ​​the workpiece hole so that the surface of the opening edge area is processed in a material-removing manner. The countersinking sleeve and the drilling tool are inserted into each other as independent components. Accordingly, an annular gap is formed between the inner circumference of the countersinking sleeve and the drilling tool. When the countersinking sleeve cutting edge engages with the workpiece surface, there is a risk that material will appear in the annular gap. In order to avoid this, according to the characterizing part of claim 1, the following measures are provided: the radially inner tip of the countersinking sleeve cutting edge is located on an inner diameter that is designed to be smaller than the outer diameter of the drilling tool at the height of the countersinking sleeve cutting edge. Accordingly, the countersinking sleeve cutting edge overlaps the annular gap between the countersinking sleeve and the drilling tool with an excess. In this way, no cutting interruption occurs in the area of ​​the annular gap, thereby preventing the appearance of material in the annular gap.

[0010] According to the invention, the countersinking sleeve and the drilling tool only cooperate functionally to keep the annular gap free of workpiece material. On the contrary, a direct mechanical coupling between the countersinking sleeve and the drilling tool should be avoided in order to reduce the tool load during the drilling process. Against this background, according to the invention, the countersinking sleeve and the drilling tool are mechanically separated from each other, that is, connected to each other in a substantially force-free manner and / or are spaced apart from each other in a contactless manner by the annular gap in the clamped state.

[0011] The countersinking tool device can have a chuck which serves as a tool receptacle for the countersinking sleeve and for the drilling tool. The chuck can be fastened to a machine spindle of a machine tool by means of an adapter. Preferably, the drilling tool and the countersinking sleeve can be clamped in the chuck independently of one another. In this case, the drilling tool and the countersinking sleeve can be mounted or removed from the chuck independently of one another. In the unclamped state, the drilling tool and the countersinking sleeve can be loosely inserted into one another as separate components with play.

[0012] In order to avoid interference / collision between the drilling tool and the countersinking sleeve, the drilling tool can have a through-portion into which the countersinking sleeve extends with its countersinking sleeve cutting edge with a radial overhang. The through-portion can extend along the axis of rotation of the drilling tool. It is preferred that the countersinking sleeve cutting edge does not extend directly into the chip cavity of the drilling tool, but instead extends into a through-portion on the back of the drill bit constructed in the drill bit profile rib portion. The through-portion can realize a profiled rib groove. The profiled rib groove can be defined by two supporting chamfers spaced apart from each other in the circumferential direction of the drill bit and a groove bottom arranged therebetween. The groove bottom can be radially inwardly shifted back by the groove depth relative to the supporting chamfer. The groove depth is designed in such a way that interference / collision with the radially inner tool tip of the countersinking sleeve can be avoided.

[0013] In a preferred hole geometry, the workpiece hole transitions into a flattened opening edge region at the hole chamfer. For this purpose, the drilling tool has at least one chamfering blade. The longitudinal edge of the drill extending along the axis of rotation of the drilling tool can transition into the chamfering blade in the direction of the clamping shank. The blade diameter of the chamfering blade increases conically in the direction of the clamping shank in order to produce the desired hole chamfer.

[0014] For machining the hole geometries described above, it is advantageous if the countersinking blade and the chamfering blade intersect one another in the overlap region on the circumferential side. In this case, the countersinking blade is arranged at a height position which, viewed in the axial direction, is between the end of the chamfering blade facing away from the drill tip and the end of the chamfering blade facing the drill tip.

[0015] For simple assembly / disassembly of the countersinking sleeve and the drilling tool, it is advantageous if the through-portion extends to the drill tip. In this case, the through-portion can be open at the drill tip so that the countersinking sleeve can be inserted into the drilling tool with its radially inwardly protruding cutting edge in the insertion direction from the drill tip to the clamping shank and can be removed therefrom in the opposite direction.

[0016] Alternatively and / or additionally, the through-portion can extend to the tool end on the shank side facing away from the drill tip. In this case, the through-portion is open at the tool end on the shank side, so that the countersinking sleeve can be inserted into the drilling tool along the insertion direction from the clamping shank to the drill tip and can be separated from it in the opposite direction.

[0017] The chuck for clamping the drilling tool and the countersinking sleeve can have a clamping channel, which has a countersinking sleeve clamping part with a large diameter for clamping the countersinking sleeve and a clamping shank clamping part with a small diameter for clamping the clamping shank. The countersinking sleeve clamping part with a larger diameter can be arranged directly at the outlet of the clamping channel, while the clamping shank clamping part with a smaller diameter is axially spaced therefrom.

[0018] Preferably, the chuck is a shrink chuck. At ambient temperature and in the unequipped state, the clamping channel of the chuck has an inner diameter that is reduced relative to the diameter of the countersinking sleeve and the clamping shank. Under the action of heat, the clamping channel of the shrink chuck can expand. As a result, the countersinking sleeve and the drilling tool can be inserted into the expanded clamping channel. When cooling, the shrink chuck shrinks onto the countersinking sleeve and the clamping shank of the drilling tool. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Embodiments of the present invention will be described below with reference to the accompanying drawings.

[0020] in:

[0021] Figures 1 to 8 Different views are shown, based on which the countersinking tool arrangement according to the invention is explained. DETAILED DESCRIPTION

[0022] exist Figure 1 1 shows a workpiece 1 machined with a countersinking tool according to the invention. With the aid of the countersinking tool, a flat workpiece surface 3 is machined flat to the theoretical dimensions. In addition, a hole 5 is made into the solid material of the workpiece in the workpiece surface 3 with the aid of the countersinking tool. The hole 5 transitions into the opening edge region of the hole 5 or into the flat workpiece surface 3 at the hole chamfer 7.

[0023] exist Figure 1 It is shown in the following Figures 2 to 7 Described drilling and countersinking tool processing in Figure 3 The workpiece geometry is shown in Figures 2 to 7 The countersinking tool is constructed in two parts, and has a drilling tool 9 and a countersinking sleeve 11. The drilling tool 9 is constructed with a clamping shank 13 and a drill body 15 ( Figure 5 ) of the spiral drilling tool. The drill body 15 is constructed as a double-edged tool, having a total of two drill-shaped ribs 17 ( Figure 3 Or 6), the drill-shaped ribs extend helically along the rotation axis R of the spiral drilling tool 9 to the drill tip. The two drill-shaped ribs 17 pass through the drill chip groove 19 ( Figure 3 or 6) are spaced apart from each other. In addition, according to Figure 3 Or 6, the drill-shaped ribs 17 are implemented so as to be point-symmetrical to each other with respect to the rotation axis R.

[0024] Each of the drill chip flutes 19 is formed on a transversely extending main cutting edge 21 on the corresponding drill-shaped rib 17 and extends to the end side in the direction of the drill tip ( Figure 2 or 3). The chip surface 23 of the drill chip groove 19 ( Figure 6 ) and the free surface 24 ( Figure 3 ) converge at the main cutting edge 21. In addition, the chip surface 23 of the drill chip flute 19 transitions to a supporting chamfer 27 ( Figure 3 The main cutting edge 21 of the drilling tool 9 and the spirally extending longitudinal edge 25 of the drill head are located at the end side, radially outer cutting tip 29 ( Figure 2 ) will meet at .

[0025] Each drill profile rib 5 has a total of two supporting chamfers 27, 31 at its drill back. The two supporting chamfers 27, 31 are spaced apart in the circumferential direction by the groove width of the profile rib groove 33. In addition, the profile rib groove 33 has a groove bottom 35 (groove depth) radially inwardly offset relative to the supporting chamfers 27, 31. Figure 6 ).

[0026] For example, Figure 2 In the embodiment, the drilling tool 9 is guided through the countersinking sleeve 11. The countersinking sleeve has two countersinking sleeve cutting edges 37 on its end side facing the drill tip, which are diagonally opposite to the rotation axis R and are set back from the drill tip of the drilling tool 9 by an axial distance Δa ( Figure 7 The two countersinking sleeve cutting edges 37 pass through the chip cavity 39 in the circumferential direction ( Figure 4 or 6) are spaced apart from each other.

[0027] According to the present invention, it is realized in Figure 4 and 5 The two components shown separately in FIG. 1 are independent of each other. The drilling tool 9 and the countersinking sleeve 11 can be inserted loosely into each other with a movement gap. In order to carry out the drilling process, the drilling tool 9 and the countersinking sleeve 11 can be inserted into the shrink chuck 40 ( Figure 3 Or 7), in the shrink chuck, the drilling tool 9 and the countersinking sleeve 11 are clamped independently of each other. On the contrary, in the unclamped state, the drilling tool 9 is loosely supported in the countersinking sleeve 11 with movement play.

[0028] In order to process Figure 1 In the workpiece geometry shown in FIG. 3 , at the workpiece surface 3 that has not yet been machined, the countersinking tool is inserted into the solid material of the workpiece to the theoretical hole depth with a drilling stroke, thereby forming a workpiece hole 5. At the end of the drilling stroke (at Figure 2The countersinking sleeve 11 uses its countersinking sleeve cutting edge 37 to cut and engage with the opening edge area of ​​the workpiece hole 5, thereby processing the opening edge area of ​​the hole 5 flat.

[0029] As exemplified in Figure 2 As shown in FIG. 1 , the drilling tool 9 has two chamfering edges 26. The edge diameter of the corresponding chamfering edge 26 increases conically in the direction of the clamping shank 13. During the drilling process, the chamfering edge 26 of the drilling tool 9 processes the hole chamfer 7. Figure 2 , - viewed in the overlapping region on the circumferential side - each of the countersinking cutting edges 37 overlaps one of the chamfering cutting edges 26. For this purpose, the countersinking cutting edges 37 are arranged at a height position which, viewed in the axial direction, is between the end of the chamfering cutting edge 26 facing away from the drill tip and the end of the chamfering cutting edge 26 facing the drill tip.

[0030] At the end of the drilling stroke, the hole chamfer 7 is produced and the workpiece surface 3 is flattened. In particular, at the end of the drilling stroke, there is the following problem: there is a gap between the inner circumference of the countersinking sleeve 11 and the drilling tool 9 (at Figure 2 6) annular gap 41. At the end of the drilling stroke, a material nodule or material accumulation may form in the annular gap 41, which may lead to premature tool breakage of the drilling tool 9.

[0031] In order to avoid this situation, the following measures are taken according to the present invention: Figure 2 or 6, the radial inner tip 43 of the corresponding countersinking sleeve blade 37 exceeds the radial amount Δr ( Figure 2 ) is extended radially inwardly. Therefore, the radially inner tip 43 of the corresponding countersinking sleeve blade 37 extends into the rib groove 33 at the drill back of the corresponding drill rib 17. Therefore, the rib groove 33 serves as a through-portion, into which the radially inner tip 43 of the countersinking sleeve blade 11 extends without contact. In this way, the annular gap 41 between the countersinking sleeve 43 and the drilling tool 9 is radially overlapped. By this radially inner overhang Δr ( Figure 2 ), the material nodule formed in the annular gap 41 can be easily removed by cutting.

[0032] exist Figure 8 , the shrink chuck 40 is shown separately. Accordingly, the shrink chuck 40 has a clamping channel 45, which is configured with a countersinking sleeve clamping portion 47 of large diameter for clamping the countersinking sleeve 11 and a drilling tool clamping portion 48 of smaller diameter for clamping the clamping shank 13. The countersinking sleeve clamping portion 47 of larger diameter is arranged directly at the outlet of the clamping channel 45, while the drilling tool clamping portion 49 of smaller diameter is axially spaced therefrom.

[0033] At ambient temperature and in the unequipped state, the clamping channel 45 of the chuck 40 has an inner diameter that is reduced relative to the diameter of the countersinking sleeve 11 and the clamping shank 13. Under the action of heat, the clamping channel 45 of the shrink chuck 40 can be expanded so that the drilling tool 9 and the countersinking sleeve 11 can be inserted into the expanded clamping channel 45. When cooling, the shrink chuck 40 shrinks onto the countersinking sleeve 11 and the clamping shank 13 of the drilling tool 9.

[0034] List of Reference Numerals

[0035] 1 Workpiece

[0036] 3. Workpiece surface

[0037] 5 holes

[0038] 7 hole chamfer

[0039] 9 Drilling tool

[0040] 11 Countersinking Bushing

[0041] 13 Clamping handle

[0042] 15 drill body

[0043] 17 drill bit rib

[0044] 19 chip groove

[0045] 21 Main Blade

[0046] 23 Chip surface

[0047] 24 free faces

[0048] 25 Drill bit longitudinal edge

[0049] 27 Support chamfer

[0050] 29 blade tip

[0051] 31 Support chamfer

[0052] Type 33 rib groove

[0053] 35 slot bottom

[0054] 37 countersinking blade

[0055] 39 Chip cavity

[0056] 40 Chuck

[0057] 41 Annular gap

[0058] 43 Radial inner tip of the countersinking sleeve

[0059] 45 clamping channel

[0060] 47 Spot facing sleeve clamping part

[0061] 49 Clamping handle clamping part

[0062] RRotation axis

[0063] Δr radial excess

Claims

1. A drilling and countersinking tool device, comprising a drilling tool (9) and a countersinking sleeve (11), wherein: The drilling tool (9) comprises a clamping shank (13) and a drill body (15) connected to the clamping shank, at least one drill-shaped rib (17) extending along the rotation axis (R) of the drill body to the drill tip, wherein the drilling tool (9) passes through a countersinking sleeve (11), and the countersinking sleeve has a countersinking sleeve cutting edge (37) on its end side facing the drill tip, which is set back from the drill tip by an axial distance (Δa), so that, in particular during the drilling process, the drilling tool (9) can be inserted into the workpiece (1) with a drilling stroke to produce a workpiece hole (5), and in the subsequent course of the drilling process, the countersinking sleeve (11) is used The countersinking sleeve cutting edge (37) is in cutting engagement with the opening edge region of the workpiece hole (5), characterized in that, at the axial height of the countersinking sleeve cutting edge (37), the radially inner tip (43) of the countersinking sleeve cutting edge (37) is located on such an inner diameter, that is, the inner diameter is designed to be smaller than the outer diameter of the drilling tool (9), in particular, in the clamped state, the countersinking sleeve (11) and the drilling tool (9) are mechanically separated from each other, that is, connected to each other in a substantially non-force-transmitting manner, and / or are spaced apart from each other by an annular gap (41) without contact or interference.

2. The countersinking tool device according to claim 1, characterized in that: The radially inner tip (43) of the countersinking sleeve cutting edge (37) is extended radially inwardly by a projection (Δr) and / or the countersinking sleeve cutting edge (37) radially overlaps the annular gap (41) between the countersinking sleeve (11) and the drilling tool (9), so that in particular no interruption of the cutting occurs in the region of the annular gap (41) and thus the presence of material in the annular gap (41) is prevented.

3. The countersinking tool device according to claim 1 or 2, characterized in that: The countersinking tool device has a chuck (40), preferably, the drilling tool (9) and the countersinking sleeve (11) can be clamped in the chuck independently of each other, and / or In the unclamped state, the drilling tool (9) and the countersinking sleeve (11) can be inserted loosely into one another as separate components with play, and / or The drilling tool (9) has a through-portion (33) into which the countersinking sleeve (11) projects with its countersinking sleeve cutting edge (37).

4. The countersinking tool device according to claim 3, characterized in that: The through portion (33) extends along the rotation axis (R) of the drilling tool (9), in particular, the through portion (33) is constructed on the drill bit back of the drill bit profile rib (17), more precisely, in particular, it is constructed as a profile rib groove, preferably, the profile rib groove (33) is defined by two supporting chamfers (27, 31) spaced apart from each other in the circumferential direction of the drill bit and a groove bottom (35) arranged therebetween, and the groove bottom is radially inwardly offset by the groove depth relative to the supporting chamfers (27, 31).

5. The countersinking tool device according to any one of the preceding claims, characterized in that: The drilling tool (9) has a chamfering edge (26) whose edge diameter increases conically toward the clamping shank (13), in particular, when viewed in the circumferential overlapping region, the countersinking sleeve edge (37) and the chamfering edge (26) of the drilling tool (9) intersect with each other.

6. The countersinking tool device according to any one of claims 3 to 5, characterized in that: The through portion (33) extends to the drill tip, that is, is open in particular at the drill tip, so that the countersinking sleeve (11) can be inserted into the drilling tool (9) along the insertion direction from the drill tip to the clamping shank (13) and can be separated from it in the opposite direction, and / or the through portion (33) extends to the tool end on the shank side facing away from the drill tip, that is, is open at the tool end on the shank side, so that the countersinking sleeve (11) can be inserted into the drilling tool (9) along the insertion direction from the clamping shank (13) to the drill tip and can be separated from it in the opposite direction.

7. A countersinking tool device according to any one of the preceding claims, characterized in that: The chuck (40) has a clamping channel (45), which has a large-diameter countersinking sleeve clamping portion (47) for clamping the countersinking sleeve (11) and a small-diameter clamping shank clamping portion (49) for clamping the clamping shank (13). In particular, the large-diameter countersinking sleeve clamping portion (47) is directly arranged at the outlet of the clamping channel (45), while the small-diameter clamping shank clamping portion (49) is axially spaced apart from the countersinking sleeve clamping portion.

8. A countersinking tool device according to any one of the preceding claims, characterized in that: The chuck (40) is a shrink chuck. At ambient temperature and in an unequipped state, the clamping channel (45) of the chuck has an inner diameter that is reduced relative to the diameter of the countersinking sleeve (11) and the clamping shank (13). Under the action of heat, the clamping channel (45) of the shrink chuck (40) can expand, so that the drilling tool (9) and the countersinking sleeve (11) can be inserted into the expanded clamping channel (45), and when cooled, the shrink chuck (40) can shrink onto the countersinking sleeve (11) and the clamping shank (13).

9. A drilling tool (9) for a countersinking tool device according to any one of the preceding claims, wherein: The drilling tool (9) comprises a clamping shank (13) and a drill body (15) connected to the clamping shank, at least one drill-shaped rib (17) extending along the rotation axis (R) of the drill body to the drill tip, wherein the drilling tool (9) passes through a countersinking sleeve (11), which has a countersinking sleeve cutting edge (37) on its end side facing the drill tip, which is set back from the drill tip by an axial distance (Δa), so that, in particular during the drilling process, the drilling tool (9) can be inserted into the workpiece (1) with a drilling stroke to produce a workpiece hole (5), and in the subsequent course of the drilling process, the countersinking sleeve (11) is used to The countersinking sleeve cutting edge (37) is in cutting engagement with the opening edge region of the workpiece hole (5), characterized in that, at the axial height of the countersinking sleeve cutting edge (37), the radially inner tip (43) of the countersinking sleeve cutting edge (37) is located on such an inner diameter, that is, the inner diameter is designed to be smaller than the outer diameter of the drilling tool (9), in particular, in the clamped state, the countersinking sleeve (11) and the drilling tool (9) are mechanically separated from each other, that is, connected to each other in a substantially non-force-transmitting manner, and / or are spaced apart from each other by an annular gap (41) without contact or interference.

10. A countersinking sleeve (11) for a countersinking tool device according to any of the preceding claims, wherein a drilling tool (9) passes through the countersinking sleeve (11), the drilling tool (9) having a clamping shank (13) and a drill body (15) connected to the clamping shank, at least one drill-shaped rib (17) extending along the rotation axis (R) of the drill body to the drill tip, wherein: The countersinking sleeve (11) has a countersinking sleeve cutting edge (37) on its end side facing the drill tip, which is set back from the drill tip by an axial distance (Δa), so that, in particular during the drilling process, a drilling tool (9) can be inserted into a workpiece (1) with a drilling stroke to produce a workpiece hole (5), and in the subsequent course of the drilling process, the countersinking sleeve (11) with its countersinking sleeve cutting edge (37) engages cuttingly with the opening edge area of ​​the workpiece hole (5), characterized in that at the axial height of the countersinking sleeve cutting edge (37), the radially inner tip (43) of the countersinking sleeve cutting edge (37) is located on an inner diameter that is smaller than the outer diameter of the drilling tool (9), in particular, in the clamped state, the countersinking sleeve (11) and the drilling tool (9) are mechanically separated from each other, that is, connected to each other in a substantially force-free manner, and / or are spaced apart from each other by an annular gap (41) without contact or interference.

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