CN216065694U

CN216065694U - Coating step bores

Info

Publication number: CN216065694U
Application number: CN202122549218.0U
Authority: CN
Inventors: 杨炳辉; 胡新民; 欧日阳
Original assignee: Dongguan Lingyi Precision Metal Co ltd
Current assignee: Dongguan Lingyi Precision Metal Co ltd
Priority date: 2021-10-22
Filing date: 2021-10-22
Publication date: 2022-03-18
Anticipated expiration: 2031-10-22

Abstract

The utility model discloses a coating step drill which comprises a first drill body, a second drill body and a drill handle, wherein the first drill body, the second drill body and the drill handle are coaxial, and the outer diameters of the first drill body and the second drill body are increased in an increasing mode; and the root part of the first drill body is provided with an arc back chipping groove on the side wall close to the transition frustum. According to the utility model, the root part of the first drill body of the step drill is provided with the root cleaning groove, so that the machining allowance can be reserved for the inertial cutting of the transition frustum, the size error of the formed step hole or the taper hole at the aperture change part is avoided, and the drilling precision of the step drill is improved; the inclined first front surface, the inclined first back surface and the interference removing surfaces are arranged on the cutting edge, so that the cutting angles of the first edge and the second edge can be adjusted conveniently according to the actual condition of a machined material part, the cutting efficiency is improved, and the smoothness of a cutting surface is improved; the aluminum titanium nitride coating is arranged on the cutting edge, so that the surface hardness of the cutter can be improved, the cutting edge is protected, and the service life of the cutter is prolonged.

Description

Coating step bores

Technical Field

The utility model relates to the technical field of machining cutters, in particular to a coated step drill.

Background

In production, step holes or taper holes are often required to be machined, the forming method is more, and the step drill is used for machining with higher efficiency. However, the inclination angle of the shoulder of the stepped hole and the taper hole machined by the stepped drill is often slightly different from the designed angle, which is determined by the tool structure and the running inertia of the drill bit, so in actual production, the operation experience of an operator often determines the machining precision of the stepped hole or the taper hole. However, with the development trend of increasingly precise products, the demands of the market on the product precision cannot be met only by depending on the experience of operators. Therefore, the present invention improves step drilling.

SUMMERY OF THE UTILITY MODEL

Aiming at the problems in the prior art, the utility model provides the coating step drill which can reserve machining allowance for inertial cutting, avoid the dimensional error of a formed step hole or a taper hole at the hole diameter change position, improve the drilling precision of the step drill, have higher surface hardness and proper ductility and have long service life.

In order to solve the technical problems, the utility model adopts a technical scheme as follows:

a coating step drill comprises a first drill body, a second drill body and a drill handle which are coaxial and have gradually increased outer diameters from bottom to top, wherein a transition frustum is formed between the first drill body and the second drill body; an arc back chipping groove is formed in the side wall, close to the transition frustum, of the root of the first drill body, and the extension line of the side wall of the transition frustum falls onto the inner wall of the back chipping groove; two cutting edges spirally surrounding the first drill body are symmetrically formed on the first drill body, the end parts of the two cutting edges are intersected at the center of the end part of the first drill body, and a chip discharge groove is formed between the two cutting edges; and the two cutting edges and the chip grooves penetrate through the transition frustum and extend to the second drill body.

As a further elaboration of the above technical solution:

in the technical scheme, the groove depth of the root cleaning groove is smaller than 1/18 of the radius of the first drill body.

In the above technical solution, each of the cutting edges includes an inclined land, and two opposite sides of the land are respectively formed with an inclined first front face and an inclined first rear face; a first edge is formed between the land and the first front face, and a second edge is formed between the land and the first rear face; the first front surface and the first rear surface are connected with the arc surface of the chip groove.

In the above technical solution, each of the cutting edges has more than one interference-removing surface formed on a side of the first relief surface.

In the above technical solution, the bottom end of the first drill body is a conical structure, and the top ends of the two cutting edges do not exceed the center of the first drill body.

In the technical scheme, the cutting edge, the chip groove, the first drill body, the transition frustum, the second drill body and the drill handle are integrally formed; and the cutting edge, the chip groove, the first drill body, the transition frustum and the second drill body are coated with aluminum titanium nitride coatings.

Compared with the prior art, the utility model has the beneficial effects that: according to the utility model, the root part of the first drill body of the step drill is provided with the root cleaning groove, so that the machining allowance can be reserved for the inertial cutting of the transition frustum, the size error of the formed step hole or the taper hole at the aperture change part is avoided, and the drilling precision of the step drill is improved; the inclined first front surface, the inclined first back surface and the interference removing surfaces are arranged on the cutting edge, so that the cutting angles of the first edge and the second edge can be adjusted conveniently according to the actual condition of a machined material part, the cutting efficiency is improved, and the smoothness of a cutting surface is improved; the aluminum titanium nitride coating is arranged on the cutting edge, so that the surface hardness of the cutter can be improved, the cutter has proper ductility, the cutting edge can be protected, and the service life of the cutter is prolonged.

Drawings

FIG. 1 is a schematic structural view of the present invention;

FIG. 2 is a schematic view of the construction of the root-removing groove of the present invention;

FIG. 4 is a schematic view of the cutting edge structure of the present invention;

FIG. 3 is a schematic end elevation view of a first drill body according to the present invention

In the figure: 10. a first drill body; 20. a second drill body; 30. a drill shank; 40. a transition frustum; 50. a root cleaning groove; 60. a cutting edge; 61. a margin; 62. a first front face; 63. a first rear face; 64. a first blade; 65. a second blade; 66. removing the interference surface; 70. chip removal groove, a, eccentricity; H. the groove is deep.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

The embodiments described by referring to the drawings are exemplary and intended to be used for explaining the present application and are not to be construed as limiting the present application. In the description of the present application, it is to be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the present application and for simplicity in description, and are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed in a particular orientation, and be operated in a particular manner, and thus should not be considered limiting. Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present application, "a plurality" means two or more unless specifically limited otherwise. In this application, unless expressly stated or limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can include, for example, fixed connections, removable connections, or integral connections; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art as appropriate. In this application, unless expressly stated or limited otherwise, the first feature "on" or "under" the second feature may comprise direct contact of the first and second features, or may comprise contact of the first and second features not directly but through another feature in between. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly above and obliquely above the second feature, or simply meaning that the first feature is at a lesser level than the second feature.

As shown in fig. 1 to 4, a coated step drill comprises a first drill body 10, a second drill body 20 and a drill shank 30 which are coaxial and have gradually increasing outer diameters from bottom to top, wherein a transition frustum 40 is formed between the first drill body 10 and the second drill body 20; an arc back chipping groove 50 is formed in the side wall, close to the transition frustum 40, of the root of the first drill body 10, and the extension line of the side wall of the transition frustum 40 falls into the inner wall of the back chipping groove 50; two cutting edges 60 spirally wound on the first drill body 10 are symmetrically formed on the first drill body 10, the end parts of the two cutting edges 60 are intersected at the center of the end part of the first drill body 10, and a chip discharge groove 70 is formed between the two cutting edges 60; both cutting edges 60 and junk slots 70 extend through the transition frustum 40 and onto the second drill body 20.

As shown in fig. 2, further, the groove depth H of the undercut groove 50 is less than 1/18 of the radius of the first drill body 10.

It can be appreciated that the back gouging groove 50 reserves a machining allowance for the transition frustum 40: when the driving device stops driving the cutter to drill, the transmission device still drives the cutter to move a small distance under the action of inertia, so that the profile and the size of the set stepped hole or the set taper hole are changed, and the back chipping groove 50 reserves a machining allowance for the movement of the small distance, so that the size error of the joint of the formed stepped hole is avoided; meanwhile, considering the stability of the structure of the cutter, the depth of the root cleaning groove 50 cannot be too deep, and only the requirement of just reserving enough machining allowance for the cutter is met; on the other hand, the allowance on the workpiece is the protruding part of the inner wall of the hole groove, and even if the protruding part is not completely cut off, the matching use of the hole is not influenced.

As a preferred embodiment of the present invention, the diameter of the first drill body 10 is 1.12mm, the taper angle of the transitional vertebral platform 40 is 90 degrees, and the depth of the root-clearing groove 50 is 0.03 mm.

As shown in fig. 3, further, each cutting edge 60 includes an inclined land 61, and opposite sides of the land 61 are formed with an inclined first front face 62 and an inclined first rear face 63, respectively; the land 61 and the first front face 62 form a first edge 64, the land 61 and the first rear face 63 form a second edge 65; the first front face 62 and the first rear face 63 each join with a flute 70.

As a preferred embodiment of the utility model, the step drill is used for processing taper holes on aluminum materials, the axial inclination angle of the blade edge 61 is 12 degrees, the axial inclination angle of the first front surface 62 is 5 degrees, and the axial inclination angle of the first rear surface is 25 degrees.

Further, each cutting edge 60 is formed with more than one interference relief surface 64 on the side of the first relief surface 63.

As shown in fig. 4, further, the bottom end portion of the first drill body 10 is tapered, and the top ends of the two cutting edges 60 do not exceed the center of the first drill body 10.

As a preferred embodiment of the utility model, the eccentricity a of the two cutting edges is between 0.01mm and 0.03 mm.

Further, the cutting edge 60, the chip groove 70, the first drill body 10, the transition frustum 40, the second drill body 20 and the drill shank 30 are integrally formed; the cutting edges 60, the chip grooves 70, the first drill body 10, the transition frustum 40 and the second drill body 20 are coated with aluminum titanium nitride coatings.

The titanium aluminum nitride has the characteristics of high hot hardness, excellent oxidation resistance, abrasion resistance and the like, and can form a compact protective layer when being solidified on the cutter, the surface hardness can reach 3500-4000HV, and the service life of the cutter can be obviously prolonged; meanwhile, the coating has proper ductility, is particularly suitable for intermittent cutting operation, and can well protect a cutting edge.

According to the utility model, the root part of the first drill body 10 of the step drill is provided with the root cleaning groove 50, so that the machining allowance can be reserved for the inertial cutting of the transition frustum 40, the size error of the formed step hole or taper hole at the hole diameter change part is avoided, and the drilling precision of the step drill is improved; the inclined first front surface 62, the inclined first back surface 63 and the interference removing surfaces 64 are arranged on the cutting edge 60, so that the cutting angles of the first edge and the second edge can be conveniently adjusted according to the actual condition of a machined material piece, the cutting efficiency is improved, and the smoothness of a cutting surface is improved; by providing the aluminum titanium nitride coating on the cutting edge 60, the surface hardness of the tool can be improved, and the tool has appropriate ductility, the cutting edge can be protected, and the service life of the tool can be prolonged.

The technical scope of the present invention is not limited to the above embodiments, and any modifications, equivalent variations and modifications made to the above embodiments according to the technical spirit of the present invention still fall within the technical scope of the present invention.

Claims

1. A coated step drill comprises a first drill body, a second drill body and a drill handle which are coaxial and have gradually increased outer diameters from bottom to top, and is characterized in that a transition frustum is formed between the first drill body and the second drill body; an arc back chipping groove is formed in the side wall, close to the transition frustum, of the root of the first drill body, and the extension line of the side wall of the transition frustum falls onto the inner wall of the back chipping groove; two cutting edges spirally surrounding the first drill body are symmetrically formed on the first drill body, the end parts of the two cutting edges are intersected at the center of the end part of the first drill body, and a chip discharge groove is formed between the two cutting edges; and the two cutting edges and the chip grooves penetrate through the transition frustum and extend to the second drill body.

2. The coated step drill of claim 1, wherein the groove depth of the root clearing groove is less than 1/18 of the radius of the first drill body.

3. A coated step drill according to claim 1, wherein each of said cutting edges includes an inclined land, opposite sides of said land being formed with an inclined first leading face and an inclined first trailing face, respectively; a first edge is formed between the land and the first front face, and a second edge is formed between the land and the first rear face; the first front surface and the first rear surface are connected with the arc surface of the chip groove.

4. A coated step drill according to claim 3, wherein each of said cutting edges is formed with more than one interference relief surface adjacent said first relief surface.

5. The coated step drill of claim 3, wherein the bottom end of the first drill body is tapered, and the top end of the cutting edges does not extend beyond the center of the first drill body.

6. A coated step drill according to any one of claims 1-5, wherein the cutting edges, chip flutes, first drill body, transition cone, second drill body, drill shank are integrally formed; and the cutting edge, the chip groove, the first drill body, the transition frustum and the second drill body are coated with aluminum titanium nitride coatings.