A drilling and milling integrated tool for suppressing burrs and a design method thereof

Abstract

The present invention provides a drilling and milling integrated tool and design method for suppressing burrs, and relates to the technical field of drilling and milling tools. The tool of the present invention includes a tool bar, a drill bit located at the front end of the tool bar, and a plurality of spiral cutting edges extending spirally along the drill bit toward the tool bar, the spiral cutting edges are arranged along the extension direction of the spiral line S1, and a spiral chip groove is formed between adjacent spiral cutting edges, a plurality of burr shearing microgrooves are arranged on the spiral cutting edge, and the burr shearing microgrooves are spirally distributed along the extension direction of the spiral line S2 on the spiral cutting edge, and the spiral line S1 and the spiral line S2 have opposite rotation directions. The present invention achieves the effect of suppressing the generation of burrs at the drilling outlet by arranging a plurality of burr shearing microgrooves on the spiral cutting edge, and the spiral line S1 where the spiral cutting edge is located and the spiral line S2 where the burr shearing microgrooves are located have opposite rotation directions, so that no additional work of removing burrs is required, thereby reducing the workload and improving the rate of high-quality products.

Description

Technical Field

[0001] The invention relates to the technical field of drilling and milling tools, and in particular to an integrated drilling and milling tool for suppressing burrs and a design method thereof. Background Art

[0002] The burrs and tears at the exit of the drill hole are formed during the drilling process due to the plastic deformation of the material and the cutting force, and they usually appear at the edge of the hole. The presence of burrs not only affects the assembly accuracy and performance of the product, but also increases the cost and difficulty of the post-processing process. At present, most of the methods for dealing with burrs are to remove them by manual removal, mechanical deburring, chemical deburring, thermal deburring, etc. after the burrs appear, but these removal methods will undoubtedly increase the workload, extend the processing time, and even cause the workpiece to be scrapped. In the manufacturing and processing of aviation parts, due to the extremely high requirements for precision and surface quality, the presence of burrs may affect the performance and safety of the parts, and corresponding measures need to be taken to remove the burrs. Therefore, there is an urgent need for an integrated drilling and milling tool that can suppress the generation of burrs during the drilling and milling process.

[0003] The above information disclosed in this Background section is only for enhancement of understanding of the background of the present disclosure and therefore it may contain information that does not constitute the prior art that is already known to one of ordinary skill in the art. Summary of the invention

[0004] The object of the present invention is to provide a drilling and milling integrated tool and a design method for suppressing burrs, so as to solve the problems raised in the above-mentioned background technology.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A drilling and milling integrated tool for suppressing burrs, comprising a tool bar, a drill bit located at the front end of the tool bar, and a plurality of spiral cutting edges spirally extending from the drill bit toward the tool bar, wherein the ball head of the drill bit is divided into an arc structure with a small curvature radius, and the ball head and the tool bar are transitioned through an arc with a large curvature radius;

[0007] The spiral cutting edge is arranged along the extension direction of the spiral line S1, and a spiral chip groove is formed between adjacent spiral cutting edges. A plurality of burr shearing microgrooves are arranged on the spiral cutting edge, and the burr shearing microgrooves are spirally distributed along the extension direction of the spiral line S2 on the spiral cutting edge, and the spiral lines S1 and S2 have opposite rotation directions.

[0008] Furthermore, the large curvature radius is twice the small curvature radius.

[0009] Furthermore, the hand direction of the helix S1 is right-handed, and the hand direction of the helix S2 is left-handed.

[0010] Furthermore, the ends of the circular arc with a small curvature radius and the circular arc with a large curvature radius that are close to each other are tangent to each other, and the end of the circular arc with a large curvature radius that is away from the small curvature radius is tangent to the tool rod.

[0011] Furthermore, the center of the arc with a small curvature radius is taken as the origin of the coordinate system , with the normal direction of the radial section of the shank as Axis, with the inner radius of the shank radial section as Axis, determined by the right-hand rule axis, and define the direction away from the ball head as The positive direction of the axis, away from the center of the cross section and to the right is Axis positive direction, to establish a rectangular coordinate system ;

[0012] The tool bar radius, large curvature radius, and small curvature radius are defined as , , , define the tangent point of the arc with large curvature radius and the arc with small curvature radius as , define the tangent point between the large radius arc and the tool bar as , the tangent point and tangent point Between The distance along the axis is defined as ,and , the origin and tangent point The connection between The acute angle between the axes is defined as ,and , define the center of the arc with large curvature radius as ,and Located on the circle where the arc with small curvature radius is located, connect the tangent line where the tangent point E is located with The acute angle between the axes is defined as ,and .

[0013] Furthermore, the acute angle between the tangent line at any point on the helix S1 and the tool axis is defined as the helix angle , and the helix angle The acute angle between the tangent line at any point on the helix S2 and the tool axis is defined as the helix angle , and the helix angle .

[0014] Furthermore, the cross-section of the burr shearing microgroove is composed of a microtooth front line, a microtooth arc and a microtooth side line connected in sequence, and the microtooth front line and the microtooth arc are tangent at one end close to each other, and the microtooth arc is tangent to the microtooth side line at one end away from the microtooth front line.

[0015] Further, the width and depth of the burr shear microgroove are defined as , ,and , the angle between the front line of the micro-tooth and the spiral cutting edge is defined as ,and , the tangent point between the micro-tooth arc and the front line of the micro-tooth is defined as , the tangent point between the micro-tooth side line and the micro-tooth arc is defined as , the intersection of the micro-tooth side line and the spiral cutting edge is defined as , the cut point and intersection The acute angle between the line connecting the micro-tooth and the front line of the micro-tooth is defined as ,and .

[0016] Furthermore, the starting point of the spiral line S2 is the tangent point , the length of the helix S2 in the tool feed direction is defined as , and the distance between two adjacent burr shear microgrooves on the same spiral cutting edge is defined as , and the length , the length of the burr shearing micro-groove in the tool feed direction is defined as , and the length , the feed per tooth is defined as ,and , is the scaling factor, and .

[0017] A design method for machining the above-mentioned integrated drilling and milling tool for suppressing burrs comprises the following steps:

[0018] Step 1, designing the ball head of the drill bit to be an arc structure with a small curvature radius, and the ball head and the tool rod are transitioned through an arc with a large curvature radius;

[0019] Step 2, a plurality of spiral cutting edges are arranged along the extending direction of the spiral line S1, and spiral chip removal grooves are formed between adjacent spiral cutting edges;

[0020] Step 3: a plurality of burr shearing micro grooves are provided on the spiral cutting edge, and the burr shearing micro grooves are distributed in a spiral manner in the extending direction of the spiral line S2, and the spiral lines S1 and S2 have opposite rotation directions.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] The integrated drilling and milling tool and design method for suppressing burrs of the present invention achieves the effect of suppressing the generation of burrs at the drill hole outlet by arranging an arc with a large curvature radius for transition near the tool rod and the ball head of the arc structure with a small curvature radius, and arranging a plurality of burr shearing microgrooves on the spiral cutting edge, and the spiral line S1 where the spiral cutting edge is located and the spiral line S2 where the burr shearing microgrooves are located are arranged in opposite directions, thereby eliminating the need for additional burr removal work, reducing workload and improving the rate of high-quality products. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a display diagram of the burr shearing micro groove in the present invention;

[0024] Figure 2 It is a front view of the integrated drilling and milling tool of the present invention;

[0025] Figure 3 for Figure 1 A magnified schematic diagram of the structure of the middle A area;

[0026] Figure 4 Schematic diagram of the tool bar and drill bit in the present invention in the X0Z coordinate system;

[0027] Figure 5 This is a view of the burr shearing microgroove in the present invention perpendicular to the spiral line S1. DETAILED DESCRIPTION

[0028] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments.

[0029] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the present invention should be understood by people with ordinary skills in the field to which the present invention belongs. The words "first", "second" and similar words used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0030] See also Figure 1-5 , the present invention provides the following technical solutions:

[0031] Embodiment 1:

[0032] A drilling and milling integrated tool for suppressing burrs, comprising a tool bar, a drill bit at the front end of the tool bar, and a plurality of spiral cutting edges 2 extending spirally from the drill bit toward the tool bar, wherein the number of the spiral cutting edges 2 is determined according to the requirements of rough and fine machining, service life, and rigidity, and is preferably 2-6, the ball head of the drill bit is divided into an arc structure with a small curvature radius, and the ball head and the tool bar are transitioned by an arc with a large curvature radius, and the tool forms a cone-like structure by setting a large and small double arc transition, so that the tool takes into account the characteristics of a drilling tool while being suitable for milling, meets the characteristics of a drilling and milling integrated tool, and ensures that the tool has a sufficient service life under the premise of being used for both drilling and milling;

[0033] The spiral cutting edge 2 is arranged along the extension direction of the spiral line S1, and a spiral chip groove 1 is formed between adjacent spiral cutting edges 2. The spiral chip groove 1 is convenient for discharging waste during the drilling and milling process. A plurality of burr shearing micro-grooves 3 are arranged on the spiral cutting edge 2, and the burr shearing micro-grooves 3 are spirally distributed along the extension direction of the spiral line S2 on the spiral cutting edge 2, and the spiral lines S1 and S2 have opposite rotation directions. The structure of the spiral cutting edge 2 is optimized by setting the burr shearing micro-grooves 3, so as to suppress the generation of burrs at the drill hole exit during the drilling and milling process.

[0034] Embodiment 2:

[0035] Embodiment 2 Based on Embodiment 1, the drill bit structure is further limited as follows: the large curvature radius is twice the small curvature radius, the ends of the small curvature radius arc and the large curvature radius arc close to each other are tangent, and the end of the large curvature radius arc away from the small curvature radius is tangent to the tool rod;

[0036] The following conditions are met in the dimension design of the drill bit and the tool holder:

[0037] The center of the arc with a small curvature radius is the origin of the coordinate system , with the normal direction of the radial section of the shank as Axis, with the inner radius of the shank radial section as Axis, determined by the right-hand rule axis, and define the direction away from the ball head as The positive direction of the axis, away from the center of the cross section and to the right is Axis positive direction, to establish a rectangular coordinate system ;

[0038] The tool bar radius, large curvature radius, and small curvature radius are defined as , , , define the tangent point of the arc with large curvature radius and the arc with small curvature radius as , define the tangent point between the large radius arc and the tool bar as , the tangent point and tangent point Between The distance along the axis is defined as ,and , the origin and tangent point The connection between The acute angle between the axes is defined as ,and , define the center of the arc with large curvature radius as ,and Located on the circle where the arc with small curvature radius is located, connect the tangent line where the tangent point E is located with The acute angle between the axes is defined as ,and The cone angles of the two common drill bits are 118 degrees and 135 degrees respectively. In the value range of Related to chip removal performance, Under the premise of It helps in the smooth discharge of debris;

[0039] According to the positional relationship, a geometric relationship model is established. The specific relationship is as follows:

[0040] ;

[0041] Then the small radius of curvature and the large radius of curvature satisfy the following relationship:

[0042] ;

[0043] The tangent point and tangent point Between The distance along the axis is defined as ,but The following relationship is satisfied:

[0044] ;

[0045] Define the point where the drill tip is away from the shank as , and the vertex and tangent point exist The distance along the axis is defined as ,but The following relationship is satisfied:

[0046] ;

[0047] The distance and distance The following relationship is satisfied:

[0048] .

[0049] Embodiment three:

[0050] Embodiment 3 further defines the structure of the spiral cutting edge 2 on the basis of Embodiment 2, specifically as follows: the hand direction of the spiral line S1 is right-handed, and the hand direction of the spiral line S2 is left-handed. Of course, the hand direction of the spiral line S1 is left-handed and the hand direction of the spiral line S2 is right-handed. The staff can set it according to the actual situation and it is not limited here. The tangent line at any point on the spiral line S1 and the tool axis (i.e. The acute angle between the two axes is defined as the helix angle , and the helix angle The acute angle between the tangent line at any point on the helix S2 and the tool axis is defined as the helix angle , and the helix angle ;

[0051] In the view perpendicular to the spiral line S1, the cross-section of the burr shear microgroove 3 is composed of a microtooth front line 4, a microtooth arc 5 and a microtooth side line 6 connected in sequence, and the microtooth front line 4 and the microtooth arc 5 are tangent at the ends close to each other, and the microtooth arc 5 is tangent to the microtooth side line 6 at the end away from the microtooth front line 4.

[0052] In the dimension design of the spiral cutting edge 2 and the burr shearing micro groove 3, the following conditions are met:

[0053] The width and depth of the burr shear microgroove 3 are defined as , ,and , the angle between the micro-tooth front line 4 and the spiral cutting edge 2 is defined as ,and , define the tangent point between the micro-tooth arc 5 and the micro-tooth front line 4 as , define the tangent point between the micro-tooth side line 6 and the micro-tooth arc 5 as , the intersection of the micro-tooth side line 6 and the spiral cutting edge 2 is defined as , the tangent point and intersection The acute angle between the line connecting the micro-tooth and the front line 4 is defined as ,and .

[0054] The starting point of spiral S2 is the tangent point , the length of the helix S2 in the tool feed direction is defined as , and the distance between two adjacent burr shear microgrooves 3 on the same spiral cutting edge 2 is defined as , and the length , the length of the burr shearing micro groove 3 in the tool feed direction is defined as , and the length , the feed per tooth is defined as ,and , is a proportional factor, which is used to ensure that the burr shearing micro groove 3 can completely remove the burrs on the entire machined surface, and .

[0055] Embodiment 4:

[0056] The present invention provides a design method for processing the integrated drilling and milling tool for suppressing burrs in the first embodiment, comprising the following steps:

[0057] Step 1, designing the ball head of the drill bit to be an arc structure with a small curvature radius, and the ball head and the tool rod are transitioned through an arc with a large curvature radius;

[0058] Step 2, a plurality of spiral cutting edges 2 are arranged along the extending direction of the spiral line S1, and spiral chip removal grooves 1 are formed between adjacent spiral cutting edges 2;

[0059] Step 3: a plurality of burr shearing micro grooves 3 are provided on the spiral cutting edge 2, and the burr shearing micro grooves 3 are distributed in a spiral manner in the extending direction of the spiral line S2, and the spiral lines S1 and S2 have opposite rotation directions.

[0060] The above formulas are all dimensionless and numerical calculations. The formula is a formula for the most recent real situation obtained by collecting a large amount of data and performing software simulation. The preset parameters in the formula are set by technicians in this field according to actual conditions.

[0061] The above embodiments may be implemented in whole or in part by software, hardware, firmware or any other combination thereof. When implemented by software, the above embodiments may be implemented in whole or in part in the form of a computer program product. Those skilled in the art may appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein may be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed by hardware or software methods depends on the specific application and design constraints of the technical solution.

[0062] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, and may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0063] The above description is only a specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application.

Claims

1. A drilling and milling integrated tool for suppressing burrs, comprising a tool bar, a drill bit located at the front end of the tool bar, and a plurality of spiral cutting edges extending spirally from the drill bit toward the tool bar, characterized in that: The ball head of the drill bit is divided into an arc structure with a small curvature radius, and the ball head and the cutter rod are transitioned by an arc with a large curvature radius; The spiral cutting edge is arranged along the extension direction of the first spiral line (S1), and a spiral chip removal groove is formed between adjacent spiral cutting edges. A plurality of burr shearing micro grooves are arranged on the spiral cutting edge, and the burr shearing micro grooves are distributed in a spiral shape along the extension direction of the second spiral line (S2) on the spiral cutting edge, and the first spiral line (S1) and the second spiral line (S2) have opposite rotation directions. The cross section of the burr shearing microgroove is composed of a micro-tooth front line, a micro-tooth circular arc and a micro-tooth side line connected in sequence, and the micro-tooth front line and the micro-tooth circular arc are tangent at one end close to each other, and the micro-tooth circular arc is tangent at one end away from the micro-tooth front line and the micro-tooth side line; The ends of the arc with a small curvature radius and the arc with a large curvature radius that are close to each other are tangent, and the end of the arc with a large curvature radius that is away from the small curvature radius is tangent to the tool bar. The tangent point of the arc with a large curvature radius and the arc with a small curvature radius is defined as , define the tangent point between the large radius arc and the tool bar as The width and depth of the burr shear microgroove are defined as , ,and The acute angle between the tangent line at any point on the first helix (S1) and the tool axis is defined as the helix angle , and the helix angle , the angle between the front line of the micro-tooth and the spiral cutting edge is defined as ,and ; The starting point of the second helix (S2) is the tangent point , the length of the second helix (S2) in the tool feed direction is defined as , and the distance between two adjacent burr shear microgrooves on the same spiral cutting edge is defined as , the tangent point and tangent point Between The distance along the axis is defined as , and the length , the length of the burr shearing micro-groove in the tool feed direction is defined as , and the length , the feed per tooth is defined as ,and , is the scaling factor, and .

2. The integrated drilling and milling tool for suppressing burrs according to claim 1, characterized in that: The large curvature radius is twice the small curvature radius.

3. The integrated drilling and milling tool for suppressing burrs according to claim 1, characterized in that: The hand direction of the first helix (S1) is right-handed, and the hand direction of the second helix (S2) is left-handed.

4. The integrated drilling and milling tool for suppressing burrs according to claim 1, characterized in that: The center of the arc with a small curvature radius is the origin of the coordinate system , with the normal direction of the radial section of the shank as Axis, with the inner radius of the shank radial section as Axis, determined by the right-hand rule axis, and define the direction away from the ball head as The positive direction of the axis, away from the center of the cross section and to the right is Axis positive direction, to establish a rectangular coordinate system ; The tool bar radius, large curvature radius, and small curvature radius are defined as , , , the tangent point and tangent point Between The distance along the axis is defined as ,and , the origin and tangent point The connection between The acute angle between the axes is defined as ,and , the center of the arc with large curvature radius is defined as ,and Located on the circle where the arc with small curvature radius is located, connect the tangent line where the tangent point E is located with The acute angle between the axes is defined as ,and .

5. The integrated drilling and milling tool for suppressing burrs according to claim 4, characterized in that: The acute angle between the tangent line at any point on the second helix (S2) and the tool axis is defined as the helix angle , and the helix angle .

6. The integrated drilling and milling tool for suppressing burrs according to claim 5, characterized in that: The tangent point between the micro-tooth arc and the front line of the micro-tooth is defined as , the tangent point between the micro-tooth side line and the micro-tooth arc is defined as , the intersection of the micro-tooth side line and the spiral cutting edge is defined as , the cut point and intersection The acute angle between the line connecting the micro-tooth and the front line of the micro-tooth is defined as ,and .

7. A design method for machining the integrated drilling and milling tool for suppressing burrs as claimed in any one of claims 1 to 6, characterized in that: The steps include: Step 1, designing the ball head of the drill bit to be an arc structure with a small curvature radius, and the ball head and the tool rod are transitioned through an arc with a large curvature radius; Step 2, arranging a plurality of spiral cutting edges along the extending direction of the first spiral line (S1), and forming spiral chip removal grooves between adjacent spiral cutting edges; Step 3, a plurality of burr shearing micro grooves are arranged on the spiral cutting edge, and the burr shearing micro grooves are distributed in a spiral manner in the extension direction of the second spiral line (S2), and the rotation directions of the first spiral line (S1) and the second spiral line (S2) are opposite.

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