A tool for machining tapered holes

Abstract

The present invention belongs to the technical field of machining tool manufacturing, and provides a tool for machining tapered holes, comprising a tool holder, a tapered hole cutting part and a drill bit connected in sequence, the drill bit can be pre-drilled, and the chip removal grooves of the tapered hole cutting part are staggered and arranged alternately, so that the chip removal space is large, the chip removal is timely and smooth, the metal removal rate is high, and the machining efficiency is increased. In addition, each cutting edge of the tool does not affect each other during the machining process, and the cutting resistance is dispersed to avoid the tool chattering phenomenon caused by resonance; the cutting edges are all in a stepped shape rising toward the tool holder to disperse the cutting resistance to avoid the tool chattering phenomenon during the machining process, and can also disperse the machining heat to avoid the occurrence of the cutting heat accumulation point phenomenon, thereby increasing the tool life.

Description

Technical Field

[0001] The present application relates to the technical field of machining tool manufacturing, and in particular to a tool for machining a tapered hole. Background Art

[0002] With the development of automobile lightweight technology, more and more aluminum alloy parts are used in automobiles. Automobile steering knuckle is also one of the important parts in the steering system. Many manufacturers use aluminum alloy materials to manufacture steering knuckles to reduce the weight of the car body. Many automobile steering knuckle parts are designed with tapered hole structures due to the needs of structure and fatigue life. The processing of tapered holes is much more difficult than that of straight holes. It is easy to vibrate the tool when rough machining the tapered hole to remove the excess, the resistance is large, and the processing efficiency is low. Especially for large tapered holes and deep tapered holes, the processing is more difficult. Summary of the invention

[0003] The embodiment of the present application provides a tool for machining tapered holes, which can greatly improve the machining efficiency of rough machining of tapered holes and avoid tool chattering. In combination with an ordinary tool for finishing machining of tapered holes, the machining of tapered holes can be completed efficiently.

[0004] To achieve the above object, the present invention provides the following technical solutions:

[0005] In an embodiment of the present application, a tool for processing a tapered hole is provided, comprising a tool holder, a tapered hole cutting part and a drill bit connected in sequence, the tapered hole cutting part comprising at least one first front chip groove close to the drill bit, at least one first rear chip groove close to the tool holder, a first cutting edge and a second cutting edge, the first front chip groove and the first rear chip groove being staggered and alternately arranged; each of the first front chip grooves is provided with the first cutting edge, and each of the first rear chip grooves is provided with the second cutting edge; the circumferential cutting trajectory of each of the first cutting edges is the same, and the circumferential cutting trajectory of each of the second cutting edges is the same; the first cutting edge and the second cutting edge are both in a stepped shape rising toward the tool holder, and the circumferential cutting trajectories of the first cutting edge and the second cutting edge are connected. In view of the characteristics of tapered hole processing, a special tool structure design is provided in this embodiment, including a tool holder, a tapered hole cutting part and a drill bit connected in sequence. The drill bit can be pre-drilled. The first front chip groove and the first rear chip groove of the tapered hole cutting part are staggered and arranged alternately. In this way, each cutting edge of the tool does not affect each other during the processing, avoiding the phenomenon of tool vibration caused by resonance. At the same time, the cutting resistance is dispersed to avoid tool vibration. The first cutting edge and the second cutting edge are both in a stepped shape rising toward the tool holder to disperse the cutting resistance and avoid tool vibration during the processing. At the same time, the processing heat can also be dispersed to avoid the phenomenon of cutting processing heat accumulation at the sharp point, thereby increasing the service life of the tool. The chip grooves are staggered and arranged alternately, the chip removal space is large, the chip removal is timely and smooth, and the chip removal of the tapered hole cutting part and the drill bit cutting part does not affect each other, the metal removal rate is high, the processing efficiency is increased, and the processing cost of the enterprise is reduced.

[0006] In some embodiments, the drill bit includes a drill tip and a drill body, the drill tip is located at the tip of the drill body, and drill chip grooves are provided on both sides of the drill tip; the drill chip grooves extend from the tip of the drill body to the bottom. In this embodiment, the drill bit has a longer chip groove, extending from the tip of the drill body to the bottom, so that the chip removal during pre-drilling and taper hole cutting does not interfere with each other.

[0007] In some embodiments, the connection between the tool handle and the tapered hole cutting part is set as an arc surface. In this embodiment, the tool handle and the tapered hole cutting part are connected by a chamfered curve transition to avoid stress concentration on the tool, enhance the rigidity of the tool body, and greatly reduce the possibility of tool vibration.

[0008] In some embodiments, the tool for machining a tapered hole is provided with a main coolant channel along its axial core, and the first front chip groove and the first rear chip groove are provided with internal coolant holes connected to the main coolant channel. In some embodiments, the tool for machining a tapered hole is provided with a main coolant channel along its axial core, and the first front chip groove and the first rear chip groove and both sides of the drill tip are provided with internal coolant holes connected to the main coolant channel. In the above embodiments, the internal coolant hole should be aligned with the cutting edge or the drill tip, and the coolant can not only wash away the chips but also take away the cutting heat, thereby reducing the tool processing temperature and increasing the tool life.

[0009] In some embodiments, the sum of the cross-sectional areas of all the inner cooling holes is not greater than the cross-sectional area of ​​the main coolant channel, so as to ensure that the coolant in the main coolant channel has sufficient pressure.

[0010] In some embodiments, a first blade groove is provided on the edge of the first front chip groove, and the first cutting edge is fixed in the first blade groove; a second blade groove is provided on the edge of the first rear chip groove, and the second cutting edge is fixed in the second blade groove; the first blade groove and the second blade groove are both open arc-shaped. In this embodiment, the blade groove is designed to be an open arc-shaped, which improves the welding strength of the blade and increases the chip removal space of the chips.

[0011] On the other hand, another embodiment of the present application provides a tool for processing tapered holes, comprising a tool holder, a tapered hole cutting part and a drill bit connected in sequence, the tapered hole cutting part comprising at least one cutting segment, each cutting segment comprising at least one chip groove evenly arranged along the circumference, and all the chip grooves of all the cutting segments are arranged alternately and staggered as a whole; a cutting edge is fixed on each of the chip grooves, and the circumferential cutting trajectory of the cutting edge of each cutting segment is the same; each of the cutting edges is in a stepped shape ascending toward the tool holder, and the circumferential cutting trajectories of the cutting edges of each cutting segment are connected. In this embodiment, a special tool structure design is provided according to the characteristics of tapered hole processing, including a tool holder, a tapered hole cutting part and a drill bit connected in sequence. The drill bit can be pre-drilled, and all the chip grooves of all cutting sections are staggered and alternately arranged as a whole. In this way, each cutting edge of the tool does not affect each other during the processing, avoiding the phenomenon of tool vibration caused by resonance. At the same time, the cutting resistance is dispersed to avoid tool vibration. Each cutting edge is in a stepped shape rising toward the tool holder to disperse the cutting resistance and avoid tool vibration during the processing. At the same time, it can also disperse the processing heat to avoid the phenomenon of cutting heat accumulation at sharp points, thereby increasing the service life of the tool. The chip grooves are staggered and alternately arranged, the chip removal space is large, the chip removal is timely and smooth, and the chip removal of the tapered hole cutting part and the drill cutting part does not affect each other, the metal removal rate is high, the processing efficiency is increased, and the processing cost of the enterprise is reduced.

[0012] In some embodiments, the drill bit includes a drill tip and a drill body, the drill tip is located at the tip of the drill body, and drill chip grooves are provided on both sides of the drill tip; the drill chip grooves extend from the tip of the drill body to the bottom. In this embodiment, the drill bit has a longer chip groove, extending from the tip of the drill body to the bottom, so that the chip removal during pre-drilling and taper hole cutting does not interfere with each other.

[0013] In some embodiments, the connection between the tool handle and the tapered hole cutting part is set as an arc surface. In this embodiment, the tool handle and the tapered hole cutting part are connected by a chamfered curve transition to avoid stress concentration on the tool, enhance the rigidity of the tool body, and greatly reduce the possibility of tool vibration.

[0014] In some embodiments, the tool for machining a tapered hole is provided with a main coolant channel along its axial core, and each of the chip flutes is provided with an internal coolant hole connected to the main coolant channel. In some embodiments, the tool for machining a tapered hole is provided with a main coolant channel along its axial core, and each of the chip flutes of the tapered hole cutting portion and both sides of the drill tip are provided with internal coolant holes connected to the main coolant channel. In the above embodiments, the internal coolant hole should be aligned with the cutting edge or the drill tip, and the coolant can not only wash away the chips but also take away the cutting heat, thereby reducing the tool processing temperature and increasing the tool life.

[0015] In some embodiments, the sum of the cross-sectional areas of all the inner cooling holes is not greater than the cross-sectional area of ​​the main coolant channel, so as to ensure that the coolant in the main coolant channel has sufficient pressure.

[0016] In some embodiments, a blade groove is provided on the edge of the chip removal groove, and the cutting edge is fixed in the blade groove; the blade groove is an open arc shape. In this embodiment, the blade groove is designed to be an open arc shape, which improves the welding strength of the blade and increases the chip removal space of the chips.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] The present invention provides a tool for processing a tapered hole. A special tool structure design is provided according to the characteristics of tapered hole processing, including a tool holder, a tapered hole cutting part and a drill bit connected in sequence. The drill bit can be pre-drilled. The chip grooves of the tapered hole cutting part are staggered and alternately arranged, so that each cutting edge of the tool does not affect each other during the processing, avoiding the phenomenon of tool vibration caused by resonance. At the same time, the cutting resistance is dispersed to avoid tool vibration. The cutting edges are all in a stepped shape rising toward the tool holder to disperse the cutting resistance to avoid tool vibration during the processing. At the same time, the processing heat can also be dispersed to avoid the phenomenon of cutting processing heat accumulation at the sharp point, thereby improving the service life of the tool. The chip grooves are staggered and alternately arranged, the chip removal space is large, the chip removal is timely and smooth, and the chip removal of the tapered hole cutting part and the drill bit cutting part does not affect each other, the metal removal rate is high, the processing efficiency is increased, and the processing cost of the enterprise is reduced. The tool of the present invention has a compact structure, a large chip removal space, and good rigidity. The chip removal grooves are staggered alternately to disperse the chip resistance, eliminate the tool vibration phenomenon caused by resonance, and improve the efficiency of excess removal processing; the step shape of the cutting edge is conducive to heat dissipation, prolongs the service life of the tool while meeting the processing rhythm requirements, and reduces the processing cost of the production enterprise. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0020] Figure 1 It is a three-dimensional structural schematic diagram of a tool for machining a tapered hole in the present application.

[0021] Figure 2 It is a schematic diagram of the main structure of a tool for machining a tapered hole in the present application.

[0022] Figure 3 It is a schematic diagram of the top view of the structure of a tool for machining a tapered hole in the present application.

[0023] Figure 4 The present application discloses an end view of a tool for machining a tapered hole in the direction of a drill tip.

[0024] Among them: 1-tool handle, 2-taper hole cutting part, 3-drill, 301-drill tip, 302-first inner cooling hole of drill, 303-second inner cooling hole of drill, 304-drill chip groove, 305-drill body, 4-arc surface, 5-main coolant channel, 6-first front chip groove, 7-first rear chip groove, 8-first cutting edge, 9-second cutting edge, 10-first blade groove, 11-second blade groove, 12-cooling hole in the tapered hole cutting part. DETAILED DESCRIPTION

[0025] The terms "first", "second", "third" and "fourth" etc. in the specification and claims of the present application and the drawings are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally includes steps or units that are not listed, or optionally includes other steps or units inherent to these processes, methods, products or devices.

[0026] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0027] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0028] Embodiment 1:

[0029] In embodiment 1, a tool for rough machining a tapered hole is provided, such as Figure 1 As shown in the figure, it includes a tool handle 1, a taper hole cutting part 2 and a drill bit 3 connected in sequence, and the tool body is made of high-speed tool steel. The tool handle of the product of the present invention can be flexibly designed into HSK tool handle type, BT tool handle type, SK tool handle and BBT tool handle type according to the type of machine tool interface. This embodiment selects the HSK-A63 tool handle type as an example to illustrate.

[0030] from Figure 2 It can be seen from the figure that the tool handle 1 is composed of a hollow conical surface at the holding end and a tool changing slot, and the tool handle 1 and the tapered hole cutting part 2 are connected by a chamfered curve transition, such as Figure 2-3 As shown in , the tool handle 1 is connected with the tapered hole cutting part 2 through the arc surface 4. The design of the arc surface 4 enhances the rigidity of tool processing, avoids stress concentration, improves the processing stability of the workpiece, and greatly reduces the possibility of tool chattering.

[0031] The drill bit 3 includes a drill tip 301 and a drill body 305. The drill tip 301 is located at the tip of the drill body 305. Drill chip grooves 304 are provided on both sides of the drill tip 301. The drill chip grooves 304 extend from the tip to the bottom of the drill body 305. Figure 2 , Figure 3 and Figure 4 It can be seen that the drill bit 3 is mainly composed of a PCD drill tip 301 or a detachable carbide replaceable drill tip 301, a first inner coolant hole 302 of the drill bit, a second inner coolant hole 303 of the drill bit, a drill chip groove 304, and a drill body 305. Extended drill chip grooves 304 are respectively provided on both sides of the drill tip 301, and the drill chip grooves 304 extend from the tip of the drill body 305 to the bottom. The drill bit 3 ensures that the tapered hole cutting part does not participate in the processing during the pre-drilling process, and the chip removal of the two does not interfere with each other. At the same time, the core thickness setting meets the processing rigidity requirements. The drill tip 301 can select a PCD drill tip or a carbide replaceable drill tip according to the material of the workpiece and the processing technology. The PCD drill tip has a long service life and the carbide replaceable drill tip is easy to replace. The tool body is provided with a main coolant channel 5 along its axial core, and its aperture is determined by the outer diameter of the tool handle and the tapered hole cutting part, which must meet both the coolant pressure requirements and the tool processing rigidity. Internal cooling holes are provided behind the drill tip 301 (i.e., on both sides of the drill tip), and the first internal cooling hole 302 and the second internal cooling hole 303 of the drill bit are both connected to the main coolant channel 5, which can play a role in cooling and assisting chip removal.

[0032] The tapered hole cutting part 2 includes two cutting segments, each of which includes two chip removal grooves evenly arranged along the circumference. Figure 2-4 As shown, the first cutting segment includes two first front chip grooves 6 close to the drill bit 1, and the second cutting segment includes two first rear chip grooves 7 close to the tool handle 1, and all the chip grooves of all the cutting segments are arranged alternately and staggered. A cutting edge is fixed on each of the chip grooves, and the circumferential cutting trajectory of the cutting edge of each cutting segment is the same. Each of the cutting edges is in the shape of a step rising toward the tool handle, and the circumferential cutting trajectory of the cutting edge of each cutting segment is connected. An open arc blade groove is provided on the edge of the chip groove, and the cutting edge is fixed in the blade groove. All cutting edges have a zero-degree axial angle and a zero-degree radial angle, that is, the cutting edge is generally straight, which not only allows the tool to have sufficient chip removal space, but also enhances the tool processing rigidity and stability, and avoids the phenomenon of tool vibration caused by lateral force on the spindle.

[0033] In conjunction with the instruction manual Figure 2-4The tapered hole cutting part 2 includes two first front chip grooves 6 close to the drill bit 1, two first rear chip grooves 7 close to the tool handle 1, a first cutting edge 8 and a second cutting edge 9. The first front chip grooves 6 and the first rear chip grooves 7 are staggered and arranged alternately. Each of the first front chip grooves 6 is provided with the first cutting edge 8, and each of the first rear chip grooves 7 is provided with the second cutting edge 9. The circumferential cutting tracks of each of the first cutting edges 8 are the same, and the circumferential cutting tracks of each of the second cutting edges 9 are the same. The first cutting edge 8 and the second cutting edge 9 are both in a step-like shape rising toward the tool handle 1, and the circumferential cutting tracks of the first cutting edge 8 and the second cutting edge 9 are continuous (the cutting edges on the same side may also have overlapping transitions on the cutting tracks). The edge of the first front chip groove 6 is provided with a first blade groove 10, and the first cutting edge 8 is fixed in the first blade groove 10. The edge of the first rear chip groove 7 is provided with a second blade groove 11, and the second cutting edge 9 is fixed in the second blade groove 11. The first blade slot 10 and the second blade slot 11 are both open arc-shaped. Here, the first cutting edge 8 and the second cutting edge 9 are both zero-degree axial angle and zero-degree radial angle, that is, the cutting edge is straight as a whole. This design avoids the machine tool spindle from being affected by the cutting lateral force during cutting, maximizes the use of the machine tool spindle rigidity, and reduces the risk of tool chattering.

[0034] The chip groove of the tapered hole cutting part 2 adopts a unique structure. The first front chip groove 6 and the first rear chip groove 7 are designed to have a zero-degree axial angle and a zero-degree radial angle, and are staggered and arranged alternately. This design structure allows the tool to have sufficient chip removal space to facilitate smooth chip removal during processing without residual debris and have sufficient processing rigidity. Each chip groove of the tapered hole cutting part 2 is provided with a tapered hole cutting part inner cooling hole 12, and the tapered hole cutting part inner cooling hole 12 is connected to the main coolant channel 5. To ensure that the coolant has sufficient pressure, the sum of the cross-sectional areas of all the inner cooling holes (including the first inner cooling hole 302 of the drill, the second inner cooling hole 303 of the drill, and the tapered hole cutting part inner cooling hole 12) shall not be greater than the cross-sectional area of ​​the main coolant channel. The openings of the inner cooling holes 12 of each tapered hole cutting part should be aligned with the cutting edge of the PCD insert. The coolant can not only wash away the chips but also take away the cutting heat, thereby reducing the tool processing temperature and increasing the tool life. The first cutting edge 8 and the second cutting edge 9 of the (PCD insert) of the tapered hole cutting part 2 are both welded to the chip removal groove by means of brazing technology. The insert groove is designed as an open arc type, which improves the welding strength of the insert and increases the chip removal space of the chips. Such a design structure can enable each cutting edge to play the best processing advantage and avoid vibration caused by resonance.

[0035] The first cutting edge 8 and the second cutting edge 9 of the tapered hole cutting part (PCD blade) are cut into steps by slow wire processing technology, and each step can be set to 2mm~5mm in length. Such a structure can disperse the cutting resistance to avoid difficult processing and tool vibration during the processing process. At the same time, it can also disperse the processing heat, avoid the occurrence of sharp points of cutting heat accumulation, and increase the service life of the tool. During the processing process, the stepped cutting edge progressively cuts into each step layer by layer, and each cutting edge supports each other, which reduces the processing resistance and greatly improves the efficiency of removing the processing allowance. In the subsequent processing, only ordinary tools for tapered hole finishing can be used to efficiently complete the finishing of the tapered hole.

[0036] In some other embodiments, the cutting segment can be designed as one or more than two according to the depth of the tapered hole. In some other embodiments, the number of chip grooves on each cutting segment can be adjusted and designed according to the needs of cutting tapered holes on different materials, the diameter of the tapered hole and the diameter of the tool, that is, the number of the first front chip groove and the first rear chip groove, as well as the first cutting edge and the second cutting edge thereon can be adjusted and designed, and the first front chip groove and the first rear chip groove can be designed as one or more than two.

[0037] The present embodiment 1 provides a tool for rough machining of tapered holes. A special tool structure design is provided according to the characteristics of tapered hole machining, including a tool holder, a tapered hole cutting part and a drill bit connected in sequence. The drill bit can be pre-drilled. The first front chip groove and the first rear chip groove of the tapered hole cutting part are staggered and arranged alternately. In this way, each cutting edge of the tool does not affect each other during the machining process, avoiding the tool vibration caused by resonance. At the same time, the cutting resistance is dispersed to avoid the tool vibration phenomenon. The first cutting edge and the second cutting edge are both in a step shape rising toward the tool holder to disperse the cutting resistance to avoid the tool vibration phenomenon during the machining process. At the same time, the machining heat can also be dispersed to avoid the occurrence of cutting heat accumulation at the sharp point, thereby increasing the service life of the tool. The chip grooves are staggered and arranged alternately, the chip removal space is large, the chip removal is timely and smooth, and the chip removal of the tapered hole cutting part and the drill bit cutting part does not affect each other. The metal removal rate is high, the machining efficiency is increased, and the machining cost of the enterprise is reduced.

[0038] In summary, the tool of the present invention has a compact structure, a large chip removal space, and good rigidity. The chip removal grooves are staggered alternately to disperse the chip resistance, eliminate the tool vibration phenomenon caused by resonance, and improve the efficiency of excess removal processing; the step shape of the cutting edge is conducive to heat dissipation, extends the service life of the tool while meeting the processing rhythm requirements, and reduces the processing cost of the production enterprise.

[0039] The embodiments of the present application are introduced in detail above. Specific examples are used in this article to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method and core idea of ​​the present application. At the same time, for general technical personnel in this field, according to the idea of ​​the present application, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A tool for machining a tapered hole, It is characterized in that It includes a tool holder, a taper hole cutting part and a drill bit connected in sequence. The tapered hole cutting portion comprises at least one first front chip groove close to the drill bit, at least one first rear chip groove close to the tool handle, a first cutting edge and a second cutting edge, wherein the first front chip groove and the first rear chip groove are alternately arranged and staggered with each other; Each of the first front chip grooves is provided with the first cutting edge, and each of the first rear chip grooves is provided with the second cutting edge; the circumferential cutting trajectory of each of the first cutting edges is the same, and the circumferential cutting trajectory of each of the second cutting edges is the same; The first cutting edge and the second cutting edge are both in a step-like shape rising toward the tool handle, and the circumferential cutting tracks of the first cutting edge and the second cutting edge are continuous; The connection between the tool handle and the tapered hole cutting part is set as a circular arc surface; A first blade groove is provided on the edge of the first front chip groove, and the first cutting edge is fixed in the first blade groove; A second blade groove is arranged on the edge of the first rear chip groove, and the second cutting edge is fixed in the second blade groove; the first blade groove and the second blade groove are both open arc-shaped; the first cutting edge and the second cutting edge are both zero-degree axial angle and zero-degree radial angle.

2. A tool for machining a tapered hole according to claim 1, It is characterized in that The drill bit comprises a drill tip and a drill body, wherein the drill tip is located at the tip of the drill body, and drill chip grooves are provided on both sides of the drill tip; the drill chip grooves extend from the tip of the drill body to the bottom end.

3. A tool for machining a tapered hole according to claim 1, It is characterized in that The tool for machining a tapered hole is provided with a main coolant channel along its axial core, and the first front chip flute and the first rear chip flute are both provided with internal cooling holes connected to the main coolant channel.

4. A tool for machining a tapered hole according to claim 2, It is characterized in that The tool for machining a tapered hole is provided with a main coolant channel along its axial core, and internal coolant holes connected to the main coolant channel are provided in the first front chip groove and the first rear chip groove and on both sides of the drill tip.

5. A tool for machining a tapered hole according to claim 3 or 4, It is characterized in that The sum of the cross-sectional areas of all the inner cooling holes is no greater than the cross-sectional area of ​​the main coolant channel.

6. A tool for machining a tapered hole, It is characterized in that It includes a tool holder, a taper hole cutting part and a drill bit connected in sequence. The tapered hole cutting part comprises at least one cutting segment, each cutting segment comprises at least one chip removal groove evenly arranged along the circumference, and all the chip removal grooves of all the cutting segments are staggered and alternately arranged as a whole; A cutting edge is fixed on each of the chip removal grooves, and the circumferential cutting trajectory of the cutting edge of each cutting segment is the same; Each of the cutting edges is in a step-like shape rising toward the tool handle, and the circumferential cutting tracks of the cutting edges of each cutting segment are continuous; The connection between the tool handle and the tapered hole cutting part is set as a circular arc surface; A blade groove is provided on the edge of the chip removal groove, and the cutting edge is fixed in the blade groove; the blade groove is an open arc shape; all cutting edges have a zero axial angle and a zero radial angle.

7. A tool for machining a tapered hole according to claim 6, wherein, the drill bit includes a drill tip and a drill body, the drill tip is located at the tip of the drill body, and drill bit chip removal grooves are provided on both sides of the drill tip; the drill bit chip removal grooves extend from the tip of the drill body to the bottom end.

8. A tool for machining a tapered hole according to claim 6, wherein, the tool for machining a tapered hole is provided with a main coolant passage along its axial core, and internal cooling holes communicating with the main coolant passage are provided in each of the chip removal grooves.

9. A tool for machining a tapered hole according to claim 7, wherein, the tool for machining a tapered hole is provided with a main coolant passage along its axial core, and internal cooling holes communicating with the main coolant passage are provided in each of the chip removal grooves of the tapered hole cutting part and on both sides of the drill tip.

10. A tool for machining a tapered hole according to claim 8 or 9, wherein, the sum of the cross-sectional areas of all the internal cooling holes is not greater than the cross-sectional area of the main coolant passage.

Images