CN211248471U

CN211248471U - Cutter for efficient composite hole making

Info

Publication number: CN211248471U
Application number: CN201921886301.3U
Authority: CN
Inventors: 刘公雨; 李灏楠
Original assignee: NINGBO XIECHENG POWER TOOLS CO Ltd
Current assignee: NINGBO XIECHENG POWER TOOLS CO Ltd
Priority date: 2019-11-04
Filing date: 2019-11-04
Publication date: 2020-08-14
Anticipated expiration: 2029-11-04

Abstract

The utility model relates to a cutter in high-efficient compound system hole, including tool bit and the cutting part of setting on the tool bit is global, its characterized in that: cutting part is including the bottom cutting portion that is used for the drilling, the first cutting portion that is used for cutting and the second cutting portion that is used for the extrusion in proper order from the head end to the tail end of tool bit, first cutting portion and second cutting portion looks interval are arranged, at least one chip groove that is used for the chip removal has been seted up on the global of tool bit, the chip groove extends to the end of tool bit, just runs through from the head end of tool bit cutting part. Compared with the prior art, the utility model has the advantages of: the special cutting thread edge part, the transition part and the extrusion thread edge part generate the effect of offsetting the axial force generated by the cutting action of part of the drilling bottom edge part on a workpiece material in the hole making process, are beneficial to reducing the deflection deformation of a cutter and the deformation of the workpiece, improve the hole processing precision and are particularly suitable for the deep hole processing working condition.

Description

Cutter for efficient composite hole making

Technical Field

The utility model belongs to the machining field, concretely relates to cutter in high-efficient compound system hole.

Background

Mechanical parts in various industrial fields often have a large number of hole features with different size and precision requirements, and need to be manufactured through a specific machining process. At present, a commonly used hole making method is mainly realized by drilling with drill bits of different structural forms, for example, twist drilling is generally used for processing common round holes of common metal components; for micro holes with the diameter smaller than 3mm, a micro drill is generally used for processing; for deep holes of members such as titanium alloy, high temperature alloy and the like, gun drills are generally used for machining; for various hole structures of carbon fiber composite materials, the types of used cutters are various, including dagger drills, multi-surface drills, three-point drills, trepanning drills and the like.

For example, chinese utility model patent No. CN201721362044.4 (No. CN207547710U) discloses a drilling tool including a drill having a double-vertex design and a shank for fixing the drill, the drill having a first cutting edge and a second cutting edge, a first vertex angle α formed by the first cutting edge being 130 ° to 150 °, and a second vertex angle β formed by the second cutting edge being 180 °. In the hole machining process, the force generated by interference between the tool and the workpiece material is mainly in the axial direction and points to the opposite direction of tool feeding, and the axial force easily causes the tool and the workpiece to deform, so that the hole precision is reduced, the surface smoothness of the hole wall is poor, and burrs at the inlet and the outlet of the hole become serious. In order to reduce the axial force, a method of reducing the tool feeding amount is often adopted, but the machining efficiency becomes low. It can be seen that the large axial force in the hole machining process is a main cause of difficulty in obtaining hole making quality and efficiency.

At present, a hole-making tool which can effectively restrain axial force and can ensure that high dimensional accuracy, high surface smoothness and high processing efficiency are obtained simultaneously in the hole processing feed process is not available.

SUMMERY OF THE UTILITY MODEL

The utility model aims to solve the technical problem that to the current situation of above-mentioned prior art, provide a cutter in the high-efficient compound system hole of the axial force that effectively lowers the cutter and wait to process the work piece and receive in the system hole in-process.

The utility model provides a technical scheme that above-mentioned technical problem adopted does: the utility model provides a cutter in compound system hole of high efficiency, includes tool bit and the cutting part of setting on the tool bit is global, its characterized in that: cutting part is including the bottom cutting portion that is used for the drilling, the first cutting portion that is used for cutting and the second cutting portion that is used for the extrusion in proper order from the head end to the tail end of tool bit, first cutting portion and second cutting portion looks interval are arranged, at least one chip groove that is used for the chip removal has been seted up on the global of tool bit, the chip groove extends to the end of tool bit, just runs through from the head end of tool bit cutting part.

In order to remove the scraps, the number of the scrap discharge grooves is at least two, and the scrap discharge grooves extend spirally and are arranged at intervals. The chip groove can also adopt a linear type.

Preferably, the first blade part comprises screw teeth spirally arranged along the axial direction, and the screw pitches P of any two adjacent screw teeth are the same. Under the condition that the thread pitches are the same, the threads can be ensured to cut internal threads which are arranged at equal intervals on the inner wall of the hole.

Further, the second cutting part comprises extrusion threads spirally arranged along the axial direction, and the thread pitches of any two adjacent extrusion threads are the same and are equal to the thread pitch p of the first cutting part.

One end of the first blade part, which is adjacent to the head end, is provided with a guide conical surface which gradually extends outwards in an inclined way from the head end to the tail end, and an included angle alpha formed between an outer tangent line of the guide conical surface and the axis of the cutter head is 30-60 degrees. The arrangement of the guide conical surface can enable the cutting screw teeth to gradually cut into the inner wall of the hole, so that the uniform material removal amount can be mutually borne from the first circle of screw teeth to the last circle of screw teeth when the inner hole threads of the workpiece are cut.

In order to counteract the axial force generated by a portion of the drilling bottom edge portion cutting the workpiece material during the hole making process, the trailing end of the bottom edge portion is spaced from the leading end of the first edge portion, and the maximum outer diameter D1 of the bottom edge portion satisfies the following relationship with the minimum inner diameter D2 of the first edge portion: d1 is not less than D2.

Further, a transition part is arranged between the first edge part and the second edge part, the inner diameter D4 of the transition part meets the requirement that D4 is not less than D2, the length of the transition part is np + delta p, n is an integer and not less than 0, and delta p meets the relation that delta p is more than 0 and less than p/2. Thus, the bending deformation of the tool and the deformation of the workpiece are reduced.

In order to completely cut and remove the internal thread cut on the hole wall by the cutter so as to obtain a high-finish surface, the cutter also comprises a third edge part for reaming, the third edge part is positioned at the tail end of the cutting part, and the head end of the third edge part is directly or indirectly connected with the tail end of the second edge part.

The tail end of the cutter head is provided with a cutter handle, the third edge part is a contraction section which contracts from the head end of the cutter handle to the second edge part, and the third edge part is connected with the tail end of the second edge part through a transition section.

Further, the rake angle α 3 of the edge of the third edge portion is 0 ° to 20 °, the relief angle α 4 of the edge of the third edge portion is 0 ° to 20 °, and the principal slip angle β is 30 ° to 80 °. In the above rake angle range, the third edge is sharp, and material can be removed with a small cutting force. In the range of the rear angle, the third edge part is stronger, is not easy to be broken due to the cutting force, and can enhance the abrasion resistance of the cutting edge; in the range of the main deflection angle, the actual chip thickness corresponding to the third edge part is relatively small, which is beneficial to reducing the cutting force born by the cutting edge with unit length and prolonging the service life of the cutter.

Compared with the prior art, the special cutting thread edge part, transition part and extrusion thread edge part of the high-efficiency composite hole making cutter of the utility model can generate the effect of offsetting the axial force generated by the cutting action of part of the drilling bottom edge part on the workpiece material in the hole making process, thereby being beneficial to reducing the deflection deformation of the cutter and the deformation of the workpiece, improving the hole processing precision and being particularly suitable for the deep hole processing working condition; in addition, the reaming edge part can thoroughly cut and remove the internal thread cut by the cutter thread on the hole wall, so that a high-cleanness surface is obtained; therefore, the deep hole manufactured by using the hole manufacturing cutter has the advantages of high machining precision, high efficiency and high quality of the obtained hole wall.

Drawings

Fig. 1 is a schematic structural diagram of an embodiment of the present invention;

FIG. 2 is a schematic view of the structure of FIG. 1 from another angle;

FIG. 3 is a cross-sectional view taken along line B-B of FIG. 2;

FIG. 4 is an enlarged schematic view of a portion of the structure of FIG. 1;

fig. 5 is a cross-sectional view a-a of fig. 4.

Detailed Description

The present invention will be described in further detail with reference to the following embodiments.

As shown in fig. 1 to 5, the high-efficiency composite hole-making tool according to the embodiment of the present invention includes a tool bit 1 and a tool shank 2 disposed at the tail end of the tool bit 1. The cutter can be made of hard alloy or high-speed steel, and the surface of the cutter is coated with a wear-resistant layer.

As shown in fig. 1 and 2, a cutting portion 1a is disposed on the circumferential surface of a tool bit 1, and the cutting portion 1a sequentially includes a bottom edge portion 3 for drilling, a first edge portion 4 for cutting, a transition portion 5, a second edge portion 6 for extruding, and a third edge portion 7 for reaming from a head end to a tail end of the tool bit 1, wherein the first edge portion 4 and the second edge portion 6 are disposed at intervals through the transition portion 5, at least one chip discharge groove 8 for discharging chips is disposed on the circumferential surface of the tool bit 1, the chip discharge groove 8 extends from the head end to the tail end of the tool bit 1 and penetrates through the cutting portion 1a, at least two chip discharge grooves 8 are spirally extended and disposed at intervals, and two chip discharge grooves 8 in this embodiment are provided, specifically, see fig. 1 and 2.

As shown in fig. 1 and 3, the trailing end of the bottom edge portion 3 and the leading end of the first edge portion 4 have a space therebetween, and the following relationship is satisfied by the maximum outer diameter D1 of the bottom edge portion 3 and the minimum inner diameter D2 of the first edge portion 4: d1 is not less than D2. The first blade part 4 comprises cutting threads 41 spirally arranged along the axial direction, the thread pitch P of any two adjacent cutting threads 41 is the same, and the thread pitch P is 0.1-2; in addition, one end of the first blade portion 4 adjacent to the head end is provided with a guide conical surface 42 which extends from the head end to the tail end and gradually inclines outwards, and an included angle α formed between an outer tangent line of the guide conical surface 42 and the axis of the cutter head is 30 to 60 degrees, as shown in fig. 1 and 3. In addition, the tooth form of the cutting screw tooth is triangular or trapezoidal, and the number of the cutting screw teeth is more than one, preferably 1-5; the cutting edge of the cutting thread is positioned at the intersection of the cutting thread and the chip groove 8 and is precisely ground to be sharp, the cutting edge rake angle alpha 1 of the cutting thread is preferably 0-20 degrees, and the cutting edge relief angle alpha 2 of the cutting thread is preferably 0-20 degrees.

As shown in fig. 1, the second blade 6 has the extrusion threads 61 spirally arranged along the axial direction, the pitch between any two adjacent extrusion threads 61 is the same and equal to the pitch P between two adjacent cutting threads 41 of the first blade 4, and the thread form, the thread inner diameter and the thread outer diameter of each extrusion thread 61 are completely the same as those of the cutting threads 41; the edge of the intersecting part of the extrusion thread and the chip groove 8 is chamfered, rounded or passivated.

As shown in FIG. 3, the inner diameter D4 of the transition section 5 satisfies D4 ≦ D2, and the length of the transition section 5 is np + Δ p, where n is an integer, n ≧ 0, and Δ p satisfies the relationship 0 < Δ p < p/2.

As shown in fig. 1 and 2, the third blade 7 is located at the tail end of the cutting portion 1a, the third blade 7 is a contracted section which is contracted from the head end of the shank 2 toward the second blade 6, the third blade 7 is connected to the tail end of the second blade 6 through a transition section 9, and the outer diameter of the transition section 9 is smaller than the minimum outer diameter of the third blade 7; the front angle alpha 3 of the cutting edge of the third edge part 7 is 0-20 degrees, the back angle alpha 4 of the cutting edge of the third edge part 7 is 0-20 degrees, and the main declination beta is 30-80 degrees; the third blade 7 has an arc portion 71 extending obliquely outward from the tip end to the tail end of the blade, and the arc portion 71 is connected to the tip end of the shank 2, so that the maximum outer diameter D5 of the third blade 7 is the same as the outer diameter of the shank 2 as shown in fig. 1. When the efficient composite hole-making cutter is used for making holes, the feed per rotation of the axial direction of the cutter is set to be equal to the pitch p of cutting (or extruding) threads.

The principle of using the efficient composite hole making cutter to make holes is as follows:

firstly, a bottom blade part used for drilling is used for drilling and removing workpiece materials to form a bottom hole with a certain allowance; then, cutting tapping is carried out on the residual material of the hole wall by the cutting screw teeth of the first edge part, and an internal thread structure is cut on the hole wall; then, the extrusion threads of the second edge part enter the internal threads of the hole wall, and due to the existence of a transition part between the head end of the edge part of the extrusion threads and the tail end of the edge part of the cutting threads, the specific interval is np + Δ p, so that the extrusion interference between the tooth-shaped rear side surface of each extrusion thread and the front side surface of the internal thread of the adjacent hole wall is caused, the interference amount is Δ p, the extrusion force pointing to the front direction, namely along the feeding direction, is generated on the cutter, the force has the reducing effect on the axial force which is opposite to the feeding direction and is from the bottom edge part, and the whole axial force in the process of feeding and drilling the cutter is effectively inhibited; and then, the third cutting part for reaming cuts and removes the residual internal thread structure and the redundant processing amount of the hole wall, and performs final finishing on the surface of the hole wall, thereby obtaining the hole characteristic with high dimensional precision and the surface of the hole wall with high finish. The above-mentioned feeding direction is a direction indicated by an outlined arrow in fig. 3.

Claims

1. The utility model provides a cutter in high-efficient compound system hole, includes tool bit (1) and sets up cutting part (1a) on tool bit (1) global, its characterized in that: cutting portion (1a) is including bottom cutting portion (3) that are used for the drilling, first cutting portion (4) that are used for cutting and be used for extruded second cutting portion (6) from the head end to the tail end of tool bit (1) in proper order, first cutting portion (4) and second cutting portion (6) looks interval are arranged, at least one chip groove (8) that are used for the chip removal have been seted up on tool bit (1) global, chip groove (8) extend to the end of tool bit (1) from the head end of tool bit (1) and run through cutting portion (1 a).

2. The tool according to claim 1, wherein: the number of the chip grooves (8) is at least two, and the chip grooves extend spirally and are arranged at intervals.

3. The tool according to claim 2, wherein: the first blade part (4) comprises cutting threads (41) which are spirally arranged along the axial direction, and the thread pitches P of any two adjacent cutting threads (41) are the same.

4. The tool according to claim 3, wherein: the second cutting part (6) comprises extrusion threads (61) which are spirally arranged along the axial direction, and the thread pitches of any two adjacent extrusion threads (61) are the same and are equal to the thread pitch P of the first cutting part (4).

5. The tool according to claim 1, wherein: one end of the first blade part (4) adjacent to the head end is provided with a guide conical surface (42) which gradually extends outwards in an inclined way from the head end to the tail end, and an included angle alpha formed between an outer tangent line of the guide conical surface (42) and the axis of the cutter head is 30-60 degrees.

6. The tool according to claim 1, wherein: the bottom edge part (3) has an interval between the tail end and the head end of the first edge part (4), and the following relationship is satisfied by the maximum outer diameter D1 of the bottom edge part (3) and the minimum inner diameter D2 of the first edge part (4): d1 is not less than D2.

7. The tool according to claim 6, wherein: a transition part (5) is arranged between the first blade part (4) and the second blade part (6), the inner diameter D4 of the transition part (5) meets the condition that D4 is not less than D2, the length of the transition part (5) is np + delta p, n is an integer and not less than 0, and delta p meets the relation that delta p is more than 0 and less than p/2.

8. The tool according to claim 1, wherein: the cutting head further comprises a third edge part (7) used for reaming, the third edge part (7) is located at the tail end of the cutting part (1a), and the head end of the third edge part (7) is directly or indirectly connected with the tail end of the second edge part (6).

9. The tool according to claim 8, wherein: the tail end of tool bit (1) has handle of a knife (2), third cutting part (7) are from the head end of handle of a knife (2) towards the contraction section of second cutting part (6) direction shrink, third cutting part (7) through changeover portion (9) with the tail end of second cutting part (6) is connected.

10. The tool according to claim 8, wherein: the front angle alpha 3 of the cutting edge of the third edge part (7) is 0-20 degrees, the back angle alpha 4 of the cutting edge of the third edge part (7) is 0-20 degrees, and the main declination angle beta is 30-80 degrees.