CN218903721U - Drilling tool - Google Patents

Abstract

The application provides a drilling tool, which comprises a clamping section and a cantilever section, wherein the cantilever section comprises a connecting part and a drilling part, the clamping section and the connecting part are integrally formed by stainless steel materials, the drilling part is made of hard alloy materials, and the drilling part is welded with the connecting part; the length of the drilling tool is L, L is more than or equal to 27.8mm and less than or equal to 38.1mm, the length of the clamping section is L1, L1 is more than or equal to 9.8mm and less than or equal to 20.1mm, the diameter of the clamping section is D1, D1 is more than or equal to 1mm and less than or equal to 4mm, and the length of the cantilever section is L2, L2 is more than or equal to 9.0mm and less than or equal to 22.0mm. The utility model provides a drill can reduce the rock when the drill high-speed rotates to improve the security of machining precision and processing.

Description

Drilling tool

Technical Field

The application belongs to the technical field of drilling tools, and more particularly relates to a drilling tool.

Background

In the aspect of hole processing of miniature workpieces (such as circuit boards and electronic product parts), the sizes of corresponding drilling tools are smaller due to smaller sizes of to-be-drilled holes, and in order to obtain better hole processing effects, high-rotation-speed operation conditions are generally selected so as to reduce the roughness of hole walls and improve the drilling quality.

Generally, the above-mentioned high-rotation-speed operation condition generally refers to a rotation speed range of 20-350 Krpm, and at the same time, the machine tool spindle generally adopts an air spindle to reduce rotation friction force and improve rotation stability; in addition, the whole drill is integrally formed by adopting hard alloy, and also is formed by adopting a drill bit made of a steel handle and a hard alloy material for welding.

However, due to the influence of the assembly coaxiality between the drill bit and the main shaft and the influence of runout of the main shaft during high-speed rotation, the drill bit is easy to deform under the action of centrifugal force during high-speed rotation, and the deformation degree is increased along with the increase of the rotating speed, so that the cantilever end of the drill bit generates larger transverse displacement. When the stress generated by the transverse displacement of the cantilever end on the drilling tool reaches the intensity limit or the service life limit which can be born by the material, the drilling tool can not bear the influence of centrifugal force caused by the processing environment, so that the deviation of the hole position of the drilling tool is large, the tool is broken and the like abnormally, and even the main shaft of the machine tool is damaged.

The above-mentioned effects are particularly remarkable in the arrangement of drill bits formed by welding steel shanks and drill bits made of cemented carbide materials.

Disclosure of Invention

An object of the embodiment of the application is to provide a drill to solve the technical problem that the drill that exists among the prior art is influenced by centrifugal force great.

In order to achieve the above object, the present application adopts a technical scheme that provides a drill, it includes:

the cantilever comprises a clamping section and a cantilever section, wherein the cantilever section comprises a connecting part and a drilling part, the clamping section and the connecting part are integrally formed by stainless steel materials, the drilling part is made of hard alloy materials, and the drilling part is welded with the connecting part;

the length of the drilling tool is L, L is more than or equal to 27.8mm and less than or equal to 38.1mm, the length of the clamping section is L1, L1 is more than or equal to 9.8mm and less than or equal to 20.1mm, the diameter of the clamping section is D1, D1 is more than or equal to 1mm and less than or equal to 4mm, and the length of the cantilever section is L2, L2 is more than or equal to 9.0mm and less than or equal to 22.0mm.

Optionally, the diameter D1 of the clamping section is 2mm, the length L1 of the clamping section is 12.55mm, and the length L2 of the cantilever section is: l2 is less than or equal to 15.25mm and less than or equal to 19.25mm.

Optionally, the diameter D1 of the clamping section is 3.175mm, the length L1 of the clamping section is 17.3mmmm, and the length L2 of the cantilever section is: l2 is more than or equal to 12.8mm and less than or equal to 20.8mm.

Optionally, the diameter D1 of the clamping section is 3.175mm, the length L1 of the clamping section is 20.1mm, and the length L2 of the cantilever section is: l2 is more than or equal to 9.0mm and less than or equal to 18.0mm.

Optionally, the diameter D1 of the clamping section is 2mm, the length L1 of the clamping section is 9.8mm, and the length L2 of the cantilever section is: l2 is more than or equal to 18mm and less than or equal to 22mm.

Optionally, the drilling part comprises a drill rod, and the length of the drill rod is L21, wherein L21 is more than or equal to 0.1mm and less than or equal to 8mm; the diameter of the drill rod is D21, and D21 is more than or equal to 0.01mm and less than or equal to 0.5mm.

Optionally, the drilling portion further comprises a first conical transition table, the first transition table and the drill rod are integrally formed, and the first transition table is welded with the connecting portion.

Optionally, the connecting portion includes the connective handle, changeover portion and is the second changeover portion that is the taper, the diameter of connective handle with the diameter of centre gripping section is unanimous, the diameter of changeover portion is less than the diameter of connective handle, the both ends of second changeover portion are connected the connective handle with the changeover portion, the changeover portion keep away from the one end of second changeover portion with drilling portion welded connection.

Optionally, the diameter of the transition section is fixedly set under the condition of the same length of the drill rod.

Optionally, the drilling portion is made of cemented tungsten carbide.

The drilling tool provided by the application has the following beneficial effects:

under the premise of meeting the clamping requirement of clamping high rotating speed, the length of the cantilever section is reduced, so that the mass center of the drilling tool is located on the clamping section or is close to the clamping section as much as possible, and the length and the mass of the cantilever section are smaller. Under the high-speed rotation working condition of the machine tool spindle, even if the spindle is jumped or coaxiality errors exist between the drill and the spindle in assembly, the drill is limited under the slightly eccentric assembly condition due to the fact that the mass of the drill is small, so that the shaking of the drill during high-speed rotation can be reduced, and the machining precision and the machining safety are improved.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are required for the embodiments or the description of the prior art will be briefly described below, it being obvious that the drawings in the following description are only some embodiments of the present application, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a perspective view of a drill bit according to some embodiments of the present application;

FIG. 2 is an exploded view of a drill bit in some embodiments of the present application;

FIG. 3 is a schematic dimensional view of a drill in accordance with some embodiments of the present application;

FIG. 4 is a schematic dimensional view of a drill in some embodiments of the present application;

fig. 5 is a schematic diagram showing deformation of a cantilever segment under the influence of centrifugal force in some embodiments of the present application.

Wherein, each reference sign in the figure:

100. a clamping section;

200. a cantilever section;

210. a connection part;

211. a connecting handle;

212. a second transition stage;

213. a transition section;

220. a drilling section;

221. a drill rod;

222. a first transition stage;

223. and a connecting section.

Detailed Description

In order to make the technical problems, technical schemes and beneficial effects to be solved by the present application more clear, the present application is further described in detail below with reference to the accompanying drawings and embodiments.

It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the present application.

It will be understood that when an element is referred to as being "mounted" or "disposed" on another element, it can be directly on the other element or be indirectly on the other element.

When an element is referred to as being "connected to" another element, it can be directly connected to the other element or be indirectly connected to the other element.

It is to be understood that the terms "length," "width," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like indicate or are based on the orientation or positional relationship shown in the drawings, merely to facilitate description of the present application and simplify description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be configured and operated in a particular orientation, and therefore should not be construed as limiting the present application.

Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature.

In the description of the present application, the meaning of "a plurality" is two or more, unless explicitly defined otherwise.

Referring to fig. 1 to 5, a drill provided in an embodiment of the present application will be described.

Referring to fig. 1 to 4, the drill bit described herein, which is formed of stainless steel material and cemented carbide welded, includes a clamping section 100 and a cantilever section 200.

Specifically, the cantilever section 200 includes a connection portion 210 and a drilling portion 220.

Wherein the connecting portion 210 and the clamping section 100 are integrally formed of a stainless steel material; the drilling portion 220 is made of cemented carbide material, and the drilling portion 220 is welded to an end of the connection portion 210 remote from the clamping section 100.

It will be appreciated that at least part of the connection portion 210 and the clamping section 100 together form the shank of the drill.

In this application, the drill is formed by stainless steel material and carbide welding, compares and makes by carbide material in whole drill, so, the drill is lower with the material cost of its manufacturing under the prerequisite of keeping the same drilling performance.

Meanwhile, it should be understood that, when the connection portion 210 of the cantilever section 200 and the clamping section 100 are made of a stainless steel material and only the drilling portion 220 of the cantilever section 200 is made of a cemented carbide material, such a structure has the following problems as compared to the entire drill made of cemented carbide material:

because the elastic modulus of the stainless steel material is smaller than that of the hard alloy material, under the working condition of high rotating speed, such as the working condition that the rotating speed is greater than or equal to 250Krpm, the large swing easily occurs due to insufficient rigidity of the handle of the drill.

Specifically, for the spindle of the machine tool, the clamping length of the drill is fixed, that is, the length of the clamping section 100 on the drill is fixed, when the length of the cantilever section 200 on the drill is long, the mass of the cantilever section 200 is increased, when the spindle is jumped and/or coaxiality assembly error exists between the drill and the spindle, the centrifugal force to which the drill is subjected is large, and also because the distance between the drilling part 220 and the clamping section 100 is large, when the drill swings under the influence of the centrifugal force, the swing amplitude of the drilling part 220 is multiplied (particularly, as shown in fig. 5, the relation between the length of the cantilever section 200 and the swing amount is shown, wherein the X axis represents the length of the cantilever section 200, and the Y represents the swing amount), so that the drilling part 220 is completely deviated from the preset rotation axis, the drilling precision is seriously reduced, and even extreme conditions such as the collision of the drill occur.

For this reason, the dimensions of the various portions of the drill are modified to reduce the mass and flexibility of the cantilever section 200 and thereby improve drilling accuracy. Specifically, the improvement is as follows:

the length of the drilling tool is L which is more than or equal to 27.8mm and less than or equal to 38.1mm, the length of the clamping section 100 is L1 which is more than or equal to 9.8mm and less than or equal to 20.1mm, the diameter of the clamping section 100 is D1 which is more than or equal to 1mm and less than or equal to 4mm, the length of the cantilever section 200 is L2 which is more than or equal to 9mm and less than or equal to 22mm.

For example, in the case of a setting in which the diameter D1 of the grip section 100 is 2mm, the length L of the drill is 27.8mm to 31.8mm; alternatively, in the case where the diameter D1 of the grip section 100 is 3.175mm, the length L of the drill is 29.1mm to 38.1mm.

Therefore, the drilling tools with different lengths of the clamping section 100 are selected according to different machining working conditions, the center of mass of the cantilever section 200 can be closer to the clamping section 100 under the condition of meeting machining requirements, and meanwhile, the rigidity of the cantilever section 200 can be effectively enhanced, so that the cantilever section 200 has higher bending resistance.

Under the working condition of high rotating speed, even if the main shaft is jumped or coaxiality errors exist between the main shaft and the drill bit in assembly, the influence of centrifugal force on the drilling part 220 can be reduced to a lower range, so that the drilling precision is improved, the situation that the drill bit 220 is broken due to overlarge deflection can be avoided to the greatest extent, and the safety of drilling processing is improved.

Further, referring to fig. 1-2, in some embodiments of the present application, the drilling portion 220 is made of tungsten cobalt-based cemented carbide.

Referring to fig. 1 to 4 in detail, the drill of the present application is described in detail below in four specific embodiments.

In a first embodiment of the present application, the diameter D1 of the gripping section 100 is 2mm, the length L1 of the gripping section 100 is 12.55mm, and the length L2 of the cantilever section 200 is 15.25mm to 19.25mm.

In this embodiment, under the condition that the length of the clamping section 100 is fixed, when the length L21 of the cantilever section 200 is continuously shortened, under the working condition that the rotation speed is 300Krpm, the following several comparative embodiments may be provided:

in the case of a cantilever segment 200 length L2 of 19.25mm, the bore hole position CPK value is 1.83;

in the case of a length L2 of the cantilever segment 200 of 18.25mm, the bore hole position CPK value is 1.91;

in the case of a cantilever segment 200 with a length L2 of 17.25mm, the bore hole position CPK value is 1.98;

in the case of a length L2 of the cantilever segment 200 of 15.25mm, the bore hole position CPK value is 2.20.

In a second embodiment of the present application, the diameter D1 of the gripping section 100 is 3.175mm, the length L1 of the gripping section 100 is 17.3mm, and the length L2 of the cantilever section 200 is 12.8mm to 20.8mm.

In this embodiment, under the condition that the length of the clamping section 100 is fixed, when the length L2 of the cantilever section 200 is continuously shortened, under the working condition that the rotation speed is 300Krpm, the following several comparative embodiments may be provided:

in the case of a length L2 of the cantilever segment 200 of 20.8mm, the bore hole position CPK value is 2.539;

in the case that the length L2 of the cantilever section 200 is 18.8mm, the hole position CPK value of the drill hole is 2.799;

in the case where the length L2 of the cantilever section 200 is 16.8mm, the hole site CPK value is 2.836;

in the case where the length L2 of the cantilever section 200 is 12.8mm, the bore hole position CPK value is 3.262.

In a third embodiment of the present application, the diameter D1 of the gripping section 100 is likewise 3.175mm, the length L1 of the gripping section 100 is 20.1mm, and the length L2 of the cantilever section 200 is 9mm to 18mm.

In this application, under the condition that the length of the clamping section 100 is fixed, when the length L2 of the cantilever section 200 is continuously shortened, under the working condition that the rotation speed is 300Krpm, the following several comparison embodiments may be provided in this embodiment:

in the case that the length L2 of the cantilever section 200 is 18mm, the hole position CPK value of the drill hole is 2.721;

in the case that the length L2 of the cantilever section 200 is 14mm, the hole position CPK value of the drill hole is 2.987;

in the case where the length L2 of the cantilever section 200 is 9mm, the hole site CPK value is 3.127.

In a fourth embodiment of the present application, the diameter D1 of the gripping section 100 is 2mm, the length L1 of the gripping section 100 is 9.8mm, and the length L2 of the cantilever section 200 is 18mm to 22mm.

In this application, under the condition that the length of the clamping section 100 is fixed, when the length L2 of the cantilever section 200 is continuously shortened, under the working condition that the rotation speed is 300Krpm, the following several comparison embodiments may be provided in this embodiment:

in the case that the length L2 of the cantilever section 200 is 18mm, the hole position CPK value is 1.88;

in the case that the length L2 of the cantilever section 200 is 20mm, the hole position CPK value of the drill hole is 1.75;

in the case of a length L2 of the cantilever segment 200 of 22mm, the bore hole position CPK value is 1.62.

In summary, as can be seen from the different comparison implementations of the foregoing embodiments, the CPK value of the drilling hole is continuously increased, i.e., the drilling accuracy is continuously increased, when the length L2 of the cantilever section 200 is continuously shortened, under otherwise identical conditions.

It is understood that in some embodiments of the present application, the drilling portion 220 includes a drill rod 221, and the length L21 (i.e., the aforementioned working length) of the drill rod 221 is 0.1mm to 8mm.

For example, the length L21 of the drill rod 221 may be 0.1mm, 1.8mm, 2.02mm, 3mm, 3.73mm, or 8mm, and may be specifically selected according to actual conditions of the machining site (e.g., height of a jig, drilling depth of an object to be machined, etc.).

It will be appreciated that the diameter D21 of the drill rod 221 is 0.01mm to 0.5mm on the basis of the previous embodiment.

For example, in the first and second embodiments described above, the diameter D21 of the drill rod 221 is 0.156mm; whereas in the third embodiment described above the diameter D21 of the drill rod 221 is 0.2mm.

It will be appreciated that referring to fig. 2, in some embodiments of the present application, the drilling portion 220 further includes a first transition stage 222 having a tapered shape, the first transition stage 222 is integrally formed with the drill pipe 221, and the first transition stage 222 is welded to the connecting portion 210.

Specifically, by providing the first transition piece 222, the rigidity of the entire drilling portion 220 can be improved, and thus the vibration resistance of the drilling portion 220 can be improved, and stress concentration due to abrupt cross-section changes at the junction between the drilling portion 220 and the connection portion 210 can be prevented, thereby improving the reliability and safety of the drilling portion 220.

It will be appreciated that, based on the foregoing arrangement, the drilling portion 220 further includes a connecting section 223, and the connecting section 223 is columnar and is used for welding connection with the transition section 213, and the first transition stage 222 connects the connecting section 223 and the drill pipe 221.

More specifically, referring to fig. 4, in some embodiments, the taper α of the first transition stage 222 may be set at 30 °.

Further, referring to fig. 2, in some embodiments of the present application, the connection portion 210 includes a connection handle 211. It will be appreciated that, because the diameter of the connection portion 210 is greatly different from the diameter of the drill rod 221, in order to reduce stress concentration caused by excessive diameter change during drilling operation, and also to avoid that the drill can enter into the positioning area on more jigs, so as to avoid that the drilling operation range of the drill is affected by the larger diameter, a second transition stage 212 and a transition section 213 are disposed between the connection handle 211 and the drilling portion 220 of the connection portion 210.

Referring to fig. 2, specifically, the diameter of the transition section 213 is smaller than the diameter of the connection handle 211 and the diameter of the transition section 213 matches the diameter of the clamping section 100, i.e., one end of the transition section 213 is welded to the connection section 223 on the drilling section 220; the second transition stage 212 has a conical shape and has two ends respectively connected to the transition section 213 and the connection handle 211.

More specifically, referring to fig. 4, in some embodiments, the taper β of the second transition stage 212 may be set at 20 °.

In this way, the transition section 213 is provided, so that the diameter of the drill bit at the part close to the drilling part 220 is gradually reduced, and the drill bit can cover a larger working range so as to adapt to more jigs with different models; at the same time, the second transition stage 212 is provided to function similarly to the first transition stage 222 described above, and also to achieve a gentle transition of the cross section to reduce stress concentrations on the drill.

Further, the diameter of the transition section 213 is fixed at the same length of the drill pipe 221. For example, in a setting where the length L21 of the drill pipe 221 is 2.02mm, the diameter D22 of the transition section 213 is 0.7mm; whereas the drill pipe 221 is 3.73mm in length L21, the diameter D22 of the transition section 213 is 0.8mm.

The foregoing description of the preferred embodiments of the present application is not intended to be limiting, but is intended to cover any and all modifications, equivalents, and alternatives falling within the spirit and principles of the present application.

Claims (10)

1. A drill bit, comprising:

the cantilever comprises a clamping section and a cantilever section, wherein the cantilever section comprises a connecting part and a drilling part, the clamping section and the connecting part are integrally formed by stainless steel materials, the drilling part is made of hard alloy materials, and the drilling part is welded with the connecting part;

the length of the drilling tool is L, L is more than or equal to 27.8mm and less than or equal to 38.1mm, the length of the clamping section is L1, L1 is more than or equal to 9.8mm and less than or equal to 20.1mm, the diameter of the clamping section is D1, D1 is more than or equal to 1mm and less than or equal to 4mm, and the length of the cantilever section is L2, L2 is more than or equal to 9.0mm and less than or equal to 22.0mm.

2. The drill bit of claim 1, wherein: the diameter D1 of the clamping section is 2mm, the length L1 of the clamping section is 12.55mm, and the length L2 of the cantilever section is as follows: l2 is less than or equal to 15.25mm and less than or equal to 19.25mm.

3. The drill bit of claim 1, wherein: the diameter D1 of the clamping section is 3.175mm, the length L1 of the clamping section is 17.3mm, and the length L2 of the cantilever section is as follows: l2 is more than or equal to 12.8mm and less than or equal to 20.8mm.

4. The drill bit of claim 1, wherein: the diameter D1 of the clamping section is 3.175mm, the length L1 of the clamping section is 20.1mm, and the length L2 of the cantilever section is as follows: l2 is more than or equal to 9.0mm and less than or equal to 18.0mm.

5. The drill bit of claim 1, wherein: the diameter D1 of the clamping section is 2mm, the length L1 of the clamping section is 9.8mm, and the length L2 of the cantilever section is as follows: l2 is more than or equal to 18mm and less than or equal to 22mm.

6. The drill according to any one of claims 1 to 5, wherein: the drilling part comprises a drill rod, and the length of the drill rod is L21, wherein L21 is more than or equal to 0.1mm and less than or equal to 8.0mm; the diameter of the drill rod is D21, and D21 is more than or equal to 0.01mm and less than or equal to 0.5mm.

7. The drill bit of claim 6, wherein: the drilling part further comprises a first conical transition table, the first transition table is integrally formed with the drill rod, and the first transition table is welded with the connecting part.

8. The drill bit of claim 7, wherein: the connecting portion comprises a connecting handle, a transition section and a conical second transition table, the diameter of the connecting handle is consistent with that of the clamping section, the diameter of the transition section is smaller than that of the connecting handle, two ends of the second transition table are respectively connected with the connecting handle and the transition section, and one end, far away from the second transition table, of the transition section is welded with the drilling portion.

9. The drill bit of claim 8, wherein: and the diameter of the transition section is fixedly set under the condition of the same length of the drill rod.

10. The drill bit of claim 1, wherein: the drilling part is made of tungsten cobalt hard alloy.

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