Drill bit

Abstract

A drill bit includes a land on which a number of bore wall machining pieces are machined, the bore wall machining pieces being arranged along an axis and forming a first set of machining bodies and a second set of machining bodies. The first set of machining bodies are located in two parallel rows of the second set of machining bodies, and the first set of machining bodies and the second set of machining bodies are distinguished through row separation groove bodies. A first separation groove body is arranged between the hole wall machining parts in the first set of machining bodies so as to form circumferential boundaries of the hole wall machining parts. In the second set of machining bodies, second partition groove bodies are arranged between the hole wall machining parts so as to form circumferential boundaries of the hole wall machining parts. In the feeding direction, the first set of machining bodies enter a machined hole earlier than the second set of machining bodies, and all hole wall machining parts in the second set of machining bodies are located right behind the first part separation groove body. Compared with a common drill bit, the drill bit provided by the utility model has the advantage that the circumferential supporting area is increased by 100-400%.

Description

Technical Field

[0001] The invention relates to a tool for machining, in particular to a hole machining tool, which can improve the cylindricity of a machined hole and the smoothness of a hole wall during machining and prolong the service life of the tool. Background Art

[0002] Drill is a general term for a type of tool used to drill through holes or blind holes in solid materials, and to expand existing holes. Common types include twist drills, flat drills, deep hole drills, reaming drills and center drills.

[0003] Most existing drill bits have problems such as short service life and easy wear, which requires frequent replacement of drill bits during drilling operations, greatly increasing operation time and cost. Furthermore, since drilling is a material removal process (rough processing), existing drill bits often cannot achieve the required dimensional accuracy and surface finish after one drilling process. It is generally necessary to subsequently obtain the required drill hole by fine processing methods such as reaming and honing to improve the cylindricity of the processed hole and the finish of the hole wall. These steps are not only cumbersome, but also require the use of different tools and processes, which can easily lead to low production efficiency and increased processing costs. In particular, in some deep hole processing, due to the large aperture ratio (for example: >10), it is difficult to perform later reaming and honing, which in turn affects the aperture, cylindricity and hole wall finish.

[0004] In order to achieve high processing efficiency and take into account the cylindricity and wall finish of the processed hole at the same time, especially to improve the mechanical and physical characteristics of the contact part between the drill bit and the hole wall, so that the drill bit edge and the hole wall can be in more stable contact, and better guiding and extrusion polishing can be achieved. Therefore, the prior art has developed a variety of technologies including auxiliary oil grooves, double edge bands, triple edge bands, and edge bands with varying widths. In specific implementation, the tool wears severely, and the hole finish and cylindricity cannot meet the processing requirements at the same time. Utility Model Content

[0005] One purpose of the utility model is to provide a drill bit, which improves the cylindricity of a hole, simplifies the processing flow, and thus improves production efficiency and reduces costs.

[0006] Another object of the utility model is to provide a drill bit to improve the smoothness of the hole wall, so as to simplify the processing process, thereby improving production efficiency and reducing costs.

[0007] Another object of the utility model is to provide a drill bit, which is applied to a twist drill to increase the service life (lifespan) of the twist drill during processing.

[0008] The drill bits provided by the utility model are a part of a tool for machining, which can be installed, assembled or connected to a handle on a rotating machine. The drill bits are a narrow and long body component with an axis arranged along the longitudinal direction of the component, including a cutting end (or drill tip) and a drill body.

[0009] In the feed direction of the drill, the drill body is a component located behind the drill tip and moves with the feed of the drill tip. Usually, a cutting edge is provided on the drill tip. At least one chip flute is provided on the drill body, and more commonly at least two chip flutes are provided. The chip flute is provided on the drill body, one end of which extends to the shank (or: the tail end of the flute), and the other end extends to the drill tip (or: the front end of the flute), and the radial outer edge surface of the drill body presents a land portion.

[0010] A drill bit comprises a cutting edge, on which a plurality of hole wall processing parts are processed and formed, and along an axis, the hole wall processing parts are arranged and form a first group of processing bodies and a second group of processing bodies;

[0011] In the feeding direction, the first group of processing bodies enters the processed holes earlier than the second group of processing bodies;

[0012] The first group of processing bodies and the second group of processing bodies are arranged in two parallel rows, and the first group of processing bodies and the second group of processing bodies are distinguished by row separation grooves;

[0013] In the first group of processing bodies, a first separating groove body is arranged between each hole wall processing piece to form a circumferential boundary of each hole wall processing piece;

[0014] In the second group of processing bodies, a second separating groove body is arranged between each hole wall processing piece to form a circumferential boundary of each hole wall processing piece;

[0015] In the feeding direction, each hole wall processing part in the second group of processing bodies is located directly behind the first partition groove body;

[0016] Along the axis, the first group of processing bodies and the second group of processing bodies are alternately arranged on the land.

[0017] In another specific implementation of the drill bit, the first dividing groove body, the second dividing groove body and the row dividing groove body are interconnected to jointly determine the circumferential boundaries of each hole wall processing part.

[0018] In another specific implementation manner of the drill bit, the depth of each first separating groove body is 0.03 mm to 0.8 mm, and the width of the groove opening is 0.02 mm to 2.50 mm.

[0019] In another specific implementation manner of the drill bit, the depth of each second separating groove body is 0.03 mm to 0.8 mm, and the width of the groove opening is 0.02 mm to 2.50 mm.

[0020] In another specific implementation manner of the drill bit, the depth of each row dividing groove is 0.03 mm to 0.8 mm.

[0021] In another specific implementation manner of the drill bit, the distance between adjacent row separation grooves is 0.020 to 2.50 mm.

[0022] The chip removal groove of the drill bit of the utility model is spiral, for example, has a radial rake angle of 0° to 35°, and is twisted spirally at an angle of 3° to 38°. When the number of the chip removal grooves is more than 2, the drill bit is twisted.

[0023] Beneficial effects achieved by the technical solution of the utility model:

[0024] The drill bit of the utility model has a cutting edge on its drill body, and a plurality of hole wall processing parts are arranged on the cutting edge, and the circumferential outer edges of the hole wall processing parts are not connected to each other, like a plurality of independent "islands" (or "cutting edge blocks"). Compared with ordinary drills with continuous cutting edges and continuous relief backs (the part adjacent to the cutting edge and the next spiral groove on the circumference of the drill), the coolant can pass through the grooves surrounding the sides of each hole wall workpiece more quickly and fully during processing, and lubricate and cool all the cutting edge blocks. Therefore, the drill with the same diameter can increase the circumferential support area by 100 to 400% without affecting cooling and lubrication while keeping the groove shape unchanged (that is, by changing the continuous cutting edge to a discontinuous cutting edge block, cooling is improved and friction is reduced, which is equivalent to setting more support area, while increasing the cutting edge width to achieve the same support area will cause processing problems such as scratches due to the inability to fully cool the friction surface), meet the requirements of processing cylindricity and surface finish, reduce reaming and grinding, thereby improving the convenience of hole wall processing, especially the life of deep hole processing tools. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a structural schematic diagram of an embodiment of a drill bit of the utility model;

[0026] Figure 2 It is a structural schematic diagram of another embodiment of the drill bit of the utility model;

[0027] Figure 3 It is a structural schematic diagram of another embodiment of the drill bit of the utility model. DETAILED DESCRIPTION

[0028] The technical solution of the utility model is described in detail below with reference to the accompanying drawings. The embodiments of the utility model are only used to illustrate the technical solution of the utility model but not to limit it. Although the utility model is described in detail with reference to the preferred embodiments, ordinary technicians in the field should understand that the technical solution of the utility model can be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the utility model, which should be included in the scope of the claims of the utility model.

[0029] Figure 1 This is a schematic diagram of the structure of an embodiment of the drill bit of the utility model. Figure 1 As shown, the drill bit of this embodiment includes a drill tip 100 (or: drill bit) and a drill body 200. In hole processing, the drill tip 100 is the first part to contact and cut the material, and it usually includes at least two cutting edges. As the drill tip 100 cuts the material, a channel is gradually formed on the object from the outside to the inside and gradually deepens. The direction in which the channel continues to deepen is also called the feed direction of the drill. Along the feed direction of the drill, the drill body 200 is a component located behind the drill tip 100, and moves with the feed of the drill tip 100 to discharge the generated chips.

[0030] The drill bit of this embodiment is a part of a tool for machining, and can be installed, assembled or connected to a handle on a rotating machine. The handle should be regarded as a narrow and long body component, having an axis arranged along the longitudinal direction of the component. One end of the drill body is connected to the handle, and the drill body extends along the axis. More commonly, the drill tip 100 and the drill body 200 are formed by processing (such as grinding with a grinding wheel, electric cutting or laser ablation) at one end of the cylindrical blank.

[0031] Usually, a cutting edge is provided on the drill tip 100, at least one chip removal groove is provided on the drill body 200, and at least one surface (usually a curved surface) arranged along the axis to perform extrusion processing on the hole wall to define the boundary of the radial outer edge of the drill body, also known as "edge or edge surface". In this embodiment, two chip removal grooves 210, 220 are provided on the circumference of the drill body 200. One end of each chip removal groove extends to the shank (or: groove tail end), and the other end extends to the drill tip (or: groove front end), so that the radial outer edge surface of the drill body 200 presents a edge portion 320, and the edge surface is the outer surface of the edge portion 230.

[0032] A plurality of cylindrical hole wall processing parts 300 are processed on the land portion 320, and the hole wall processing parts 300 are arranged and formed into a first group of processing bodies 410 and a second group of processing bodies 420 distributed along the axis. The first group of processing bodies 410 are located in two parallel rows of the second group of processing bodies 420, and the first group of processing bodies and the second group of processing bodies are distinguished by a row dividing groove 430. In the feeding direction, the first group of processing bodies 410 enters the processed hole earlier than the second group of processing bodies 420.

[0033] A first partitioning groove 412 is disposed between each hole wall processing member 411 of the first processing body 410 to form a circumferential boundary B1 of each hole wall processing member. A second partitioning groove 422 is disposed between each hole wall processing member 421 of the second processing body 420 to form a circumferential boundary B2 of each hole wall processing member.

[0034] The first partition groove body 412, the second partition groove body 422 and the row partition groove body 430 are arranged to be interconnected so as to jointly determine the circumferential boundary of each hole wall processing part. For example, the first partition groove body 412 and the second partition groove body 422 are both axially oriented, and the row partition groove body 430 is circumferentially oriented, so that in the feed direction, each hole wall processing part 421 in the second group of processing bodies is located directly behind the first partition groove body 411.

[0035] The hole wall processing part 300 may also be in the form of a multi-prism type, such as a triangular prism type (see Figure 2 ), quadrangular prism, pentagonal prism and hexagonal prism (see Figure 3 )wait.

[0036] In this embodiment, the width of each groove body is 0.02mm~2.50mm, the length is between 0.03mm and 2.50mm, and the interval between adjacent groove bodies is between 0.02mm and 2.50mm. Compared with the first dividing groove body 412 and the second dividing groove body 422, the length of the row dividing groove body 430 is usually several times, such as: 2 times, 5 times, 10 times, 15 times or more times. The grooves are evenly distributed on the tool surface, so that the margin surfaces are evenly spaced to form an "islanded" processing surface, so that the circumferential outer edges of the hole wall processing parts are not connected to each other, like multiple independent "islands" (or "margin blocks"), which not only increases the contact area with the cooling medium, but also improves the oil film coating while ironing and extruding the hole wall, improves the circumferential and axial thermal stress distribution of the hole wall, and also optimizes the contact between the margin and the hole wall, and homogenizes the support area of ​​the margin and the hole wall in both the circumferential and axial directions, improves the self-guiding property, and helps the drill to achieve better centering and better maintain cylindricity, so that the drill margin and the hole wall are in more stable contact, achieving better guiding and extrusion polishing effects.

[0037] It has been verified that the tool of this embodiment has a service life of a cumulative hole processing depth of 400 meters, a hole finish within Ra3.2, and a cylindricity within 0.02mm / 100mm.

Claims

1. A drill bit, comprising a cutting edge, characterized in that A plurality of hole wall processing parts are formed on the edge band, and the hole wall processing parts are arranged along the axis to form a first group of processing bodies and a second group of processing bodies; The first group of processing bodies and the second group of processing bodies are arranged in two parallel rows, and the first group of processing bodies and the second group of processing bodies are distinguished by row separation grooves; In the first group of processing bodies, a first separating groove body is arranged between each hole wall processing piece to form a circumferential boundary of each hole wall processing piece; In the second group of processing bodies, a second separating groove body is arranged between each hole wall processing piece to form a circumferential boundary of each hole wall processing piece; In the feeding direction, the first group of processing bodies enters the processed holes earlier than the second group of processing bodies, and each hole wall processing part in the second group of processing bodies is located directly behind the first partition groove body.

2. The drill bit according to claim 1, characterized in that Along the axis, the first group of processing bodies and the second group of processing bodies are alternately arranged on the land.

3. The drill bit according to claim 1, characterized in that The depth of each first partition groove body is 0.03mm-0.8mm, and the width of the groove opening is 0.02mm-2.50mm.

4. The drill bit according to claim 1, characterized in that The depth of each second partition groove body is 0.03mm-0.8mm, and the width of the groove opening is 0.02mm-2.50mm.

5. The drill bit according to claim 1, characterized in that The depth of each row separation groove is 0.03mm to 0.8mm.

6. The drill bit according to claim 1, characterized in that The distance between adjacent row separation slots is 0.020 to 2.50 mm.

7. The drill bit according to claim 1, characterized in that The chip flutes are spiral shaped.

8. The drill bit according to claim 7, characterized in that The spiral radial rake angle is 0° to 35°, and the spiral is twisted at an angle of 3° to 38°.

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