Deep hole drilling bit suitable for MQL cooling

Abstract

The utility model discloses a deep hole drilling bit suitable for MQL cooling. The deep hole drilling bit comprises a cutting part, a cutter handle part and an MQL cooling part. The upper end of the cutting part is integrally formed at the lower end of the cylindrical cutter handle part, two cutting edges are symmetrically arranged on the lower end face of an inverted-cone-shaped cutting body of the cutting part, two spiral cutter backs and chip grooves are symmetrically arranged on the circumferential face of the inverted-cone-shaped cutting body of the cutting part, and a main edge belt is arranged on the edge, close to the front cutter face, of each cutter back. The middle of the lower end of the main edge strip is ground to form a relief angle grinding plane, an unprocessed arc surface at the lower end forms a cutting contact surface with smaller width, and the relief angle grinding plane and the cutting contact surface form a combined edge strip; a spiral cooling hole of the MQL cooling part axially penetrates through the upper end face of the cutter handle part and the lower end face of the cutting part. The utility model has the effects of slight circumferential blade abrasion, improved durability, long service life, high processing efficiency and high product yield.

Description

Technical Field

[0001] The utility model relates to the field of automobile parts processing, and particularly relates to a deep hole drilling bit suitable for MQL cooling. Background Art

[0002] In the process of mechanical manufacturing and processing, especially when processing automobile parts, deep holes often need to be drilled. At present, carbide deep hole drills are preferred. Carbide deep hole drills are easy to manufacture, have a spiral rake face that is conducive to chip evacuation, and can ensure high production efficiency and hole quality. The problem is that when the processing depth is large and the on-site conditions are harsh, especially when drilling holes with a length-diameter ratio greater than 20, the cutting chips are difficult to evacuate in time. The cooling method of carbide deep hole drills is often the MQL cooling method (i.e., the micro-oil mist lubrication method). In summary, this causes high processing temperature, rapid tool wear, low tool durability, and low service life; at the same time, the drill bit needs to be frequently ground, reducing the processing speed, and at the same time causing poor drilling and increased processing and manufacturing costs. Summary of the Utility Model

[0003] In order to solve one or more of the above problems, the utility model provides a deep hole drilling bit suitable for MQL cooling.

[0004] According to one aspect of the utility model, the deep hole drilling bit suitable for MQL cooling includes a cutting part, a tool shank part, and an MQL cooling part;

[0005] The upper end of the cutting part is integrally formed at the lower end of the cylindrical tool shank part. The cutting part includes an inverted conical cutting body. Two cutting edges are symmetrically arranged on the lower end face of the cutting body, and two axially spiral tool backs are symmetrically arranged on the circumferential surface. Two axially spiral chip evacuation grooves are formed between the two tool backs. A main cutting edge band that is axially spiral and has an arc-shaped end face is arranged at the edge of each tool back close to the rake face. The middle of the lower end of the main cutting edge band is processed by back angle grinding to form a back angle grinding plane, and the unprocessed arc surface at the lower end forms a cutting contact surface with a smaller width. The back angle grinding plane and the cutting contact surface constitute a combined cutting edge band;

[0006] The two spiral cooling holes of the MQL cooling part axially penetrate the upper end face of the tool shank part and the lower end face of the cutting part.

[0007] In some embodiments, the back angle of the back angle grinding plane is 0.2°.

[0008] In some embodiments, the total width of the main cutting edge band is 0.06 times the tool diameter, and the width of the cutting contact surface is 0.015 times the tool diameter;

[0009] Or the length of the combined cutting edge band is 1.5 times the tool diameter.

[0010] In some embodiments, the tool diameter is 8 mm, the length of the combined land is 12 mm, the total width of the primary land is 0.48 mm, and the width of the cutting contact surface is 0.12 mm.

[0011] In some embodiments, a secondary land with a helical axial shape and an arc-shaped end face is also provided at the middle of each tool flank.

[0012] In some embodiments, a tapered clearance section is also provided between the cutting part and the tool shank. The chip flutes and the tool flanks of the cutting body extend to the end of the clearance section. The tool flank of the clearance section is a smooth and unprocessed surface, and the diameter of the clearance section is lower than the diameter of the cutting body.

[0013] In some embodiments, when the tool diameter is greater than or equal to 8 mm, the diameter of the clearance section is 0.3 mm lower than the diameter of the cutting body 10;

[0014] When the tool diameter is less than 8 mm, the diameter of the clearance section is 0.2 mm lower than the diameter of the cutting body.

[0015] In some embodiments, the deep hole drilling bit is also applicable to dry cutting or ordinary cutting scenarios.

[0016] In some embodiments, the deep hole drilling bit is made of cemented carbide material with an ISO grade of K30-40.

[0017] In some embodiments, the back angle grinding plane is machined by a five-axis grinding machine.

[0018] The deep hole drilling bit applicable to MQL cooling adopts a combined land formed by setting a primary land, a back angle grinding plane and a cutting contact surface at the lower end of the primary land. The width of the cutting contact surface in the combined land is very small and narrow, ensuring a smaller contact area during drilling, so the cutting load is significantly reduced, especially the axial force drops significantly, effectively reducing tool wear in high-temperature and harsh environments. Its beneficial effects are as follows: First, the circumferential edge wear of the deep hole drilling bit with this setting is effectively slowed down, the durability is significantly improved, and the service life is increased; Second, the wear is slight, which helps the subsequent tool grinding, reducing the grinding difficulty and workload; Third, the service life of the drill bit increases, the frequency of grinding the drill bit within the same working time is reduced, the working time of the equipment is increased, and the processing efficiency is effectively improved; Fourth, the drill bit has a small load, can maintain a good working condition for a long time, effectively reduces the occurrence of poor drilling, and at the same time this structure can be directly ground and improved on the original drill bit, further reducing the processing and manufacturing cost; Fifth, the drill bit with this structure is applicable to scenarios with poor processing environments and little cutting coolant. Description of the Drawings

[0019] Figure 1 It is a front view schematic diagram of a deep hole drilling bit applicable to MQL cooling according to an embodiment of the present invention;

[0020] Figure 2 is Figure 1 a partial enlarged schematic view of the cutting part shown;

[0021] Figure 3 is Figure 2 a top view schematic of a deep hole drilling bit suitable for MQL cooling shown;

[0022] Figure 4 is Figure 3 a schematic view of the combined land shown;

[0023] Cutting part 1, cutting body 10, cutting edge 101, flank 11, chip flute 12, main land 13, combined land 130, flank grinding plane 131, cutting contact surface 132, secondary land 14;

[0024] Shank part 2;

[0025] MQL cooling part 3, cooling hole 31;

[0026] Relieved section 4. Detailed implementation mode

[0027] The present utility model will be further described in detail below with reference to the accompanying drawings. It should be noted that the terms "front", "rear", "left", "right", "upper" and "lower" used in the following description refer to the directions in the drawings, and the terms "inner" and "outer" respectively refer to the directions towards or away from the geometric center of a specific component.

[0028] Figures 1 to 4 Schematically shows a deep hole drilling bit suitable for MQL cooling according to an embodiment of the present utility model. As shown in the figure, the deep hole drilling bit suitable for MQL cooling includes a cutting part 1, a shank part 2 and an MQL cooling part 3;

[0029] The upper end of the cutting part 1 is integrally formed at the lower end of the cylindrical shank part 2. The cutting part 1 includes a conical cutting body 10 with a gradually decreasing diameter from bottom to top. Two cutting edges 101 are symmetrically arranged on the lower end face of the cutting body 10, and two axially spiral flanks 11 are symmetrically arranged on the circumferential surface. Two axially spiral chip flutes 12 are formed between the two flanks 11. The chip flutes 12 are preferably of a common profile with a rake angle of 18°. An axially spiral and end-face arc-shaped main land 13 is provided at the edge of each flank 11 close to the rake face. The middle of the lower end of the main land 13 is processed by flank grinding to form a flank grinding plane 131, and the unprocessed arc surface at the lower end forms a cutting contact surface 132 with a smaller width. The flank grinding plane 131 and the cutting contact surface 132 constitute the combined land 130. The flank angle of the flank grinding plane 131 is preferably 0.2°.

[0030] The two spiral cooling holes 31 of the MQL cooling part 3 axially penetrate through the upper end surface of the tool shank part 2 and the lower end surface of the cutting part 1. Preferably, the spiral shape of the cooling hole 31 is similar to the spiral shape of the tool back 11.

[0031] This deep-hole drilling bit suitable for MQL cooling is provided with a main cutting edge band 13. A combined cutting edge band 130 composed of a rear angle grinding plane 131 and a cutting contact surface 132 is arranged at the lower end of the main cutting edge band 13. Among them, the width of the cutting contact surface 132 in the combined cutting edge band 30 is very small and narrow, ensuring a smaller contact area during drilling. Therefore, the cutting load is significantly reduced, especially the axial force drops significantly, effectively reducing tool wear in a high-temperature and harsh environment. Its beneficial effects are as follows: First, the circumferential edge wear of the deep-hole drilling bit with this setting is effectively slowed down, the durability is significantly improved, and the service life is increased; Second, the wear is slight, which helps the subsequent grinding of the tool, reducing the grinding difficulty and workload; Third, the service life of the drill bit increases, the frequency of grinding the drill bit within the same working time is reduced, the working time of equipment use is increased, and the processing efficiency is effectively improved; Fourth, the drill bit bears less load, can maintain good working conditions for a long time, effectively reduces the occurrence of poor drilling, and at the same time, this structure can be directly ground and improved on the original drill bit, further reducing the processing and manufacturing cost; Fifth, the drill bit with this structure is suitable for scenarios with poor processing environment and less cutting coolant.

[0032] Furthermore, the total width of the main cutting edge band 13 is 0.06 times the tool diameter, and the width of the cutting contact surface 132 is 0.015 times the tool diameter; Preferably, the length of the combined cutting edge band 130 is 1.5 times the tool diameter. Preferably, the tool diameter is 8 mm, the length of the combined cutting edge band 130 is 12 mm, the total width of the main cutting edge band 13 is 0.48 mm, and the width of the cutting contact surface 132 is 0.12 mm. Its beneficial effects are: This setting can obtain the optimal cutting load, the tool life can be increased by 50%, ensuring a smaller contact area during the processing, a smaller cutting load, and the wear of the cutting edge band is significantly slower than that of an ordinary deep-hole drill, and the durability is significantly improved, and the durability can be increased by 50%.

[0033] In a group of comparative designs, when the drilling depth is 84 mm and the working conditions are set as: cutting speed 58 m / min and feed speed 506 mm / min, the cutting load of the original ordinary drill bit is 20%, and it can only drill 260 pieces. The cutting load of this design is 16%, and it can drill 400 pieces. Therefore, the service life and durability can be increased by more than 50%.

[0034] Furthermore, a secondary cutting edge band 14 with a spiral shape axially and an arc shape on the end face is also provided at the middle of each tool back 11. Its beneficial effects are: The secondary cutting edge band 14 can improve the straightness and position accuracy of tool processing, and improve the quality of the processed hole position.

[0035] Further, a tapered clearance section 4 is provided between the cutting part 1 and the tool shank part 2. The diameter of the tapered shape gradually decreases from bottom to top. The chip flutes 12 and the tool back 11 of the cutting body 10 extend to the end of the clearance section 4. The tool back 11 of the clearance section 4 is a smooth unprocessed surface, and the diameter of the clearance section 4 is lower than the diameter of the cutting body 10. Preferably, when the tool diameter is greater than or equal to 8 mm, the diameter of the clearance section 4 is 0.3 mm lower than the diameter of the cutting body 10; when the tool diameter is less than 8 mm, the diameter of the clearance section 4 is 0.2 mm lower than the diameter of the cutting body 10. The beneficial effect is that the tapered clearance section 4 can prevent upper-end interference with the newly machined hole and avoid defects caused by damage to the machining features.

[0036] Preferably, the diameters of the clearance section 4 and the cutting body 10 gradually decrease from bottom to top, decreasing by 0.4 mm per 100 mm. The beneficial effect is that this setting reduces interference and is beneficial to machining.

[0037] Preferably, the deep hole drilling bit is made of cemented carbide material of ISO grade K30-40. The beneficial effect is that this selection of cemented carbide material has better drilling performance and service life.

[0038] Preferably, the back angle grinding plane 131 is machined by a five-axis grinding machine. The beneficial effect is that this selection has good machining accuracy.

[0039] Further, the deep hole drilling bit is also applicable to dry cutting or ordinary cutting scenarios. The beneficial effect is that this product can not only be applied to harsh environments but also to ordinary environments, with a wide application range.

[0040] The above are only some embodiments of the present utility model. For those of ordinary skill in the art, without departing from the creative concept of the present utility model, several deformations and improvements can still be made, and these all belong to the protection scope of the present utility model.

Claims

1. A deep hole drilling bit suitable for MQL cooling, characterized in that, It includes a cutting part (1), a tool shank part (2), and an MQL cooling part (3); The upper end of the cutting part (1) is integrally formed at the lower end of the cylindrical tool shank part (2). The cutting part (1) includes an inverted conical cutting body (10). Two cutting edges (101) are symmetrically arranged on the lower end face of the cutting body (10), and two axially helical tool backs (11) are symmetrically arranged on the circumferential surface. Two axially helical chip flutes (12) are formed between the two tool backs (11). At the edge of each tool back (11) near the rake face, there is a main cutting edge band (13) that is axially helical and has an arc-shaped end face. The middle of the lower end of the main cutting edge band (13) is processed by back angle grinding to form a back angle grinding plane (131), and the unprocessed arc surface at the lower end forms a cutting contact surface (132). The back angle grinding plane (131) and the cutting contact surface (132) constitute a combined cutting edge band (130); The two helical cooling holes (31) of the MQL cooling part (3) axially penetrate the upper end face of the tool shank part (2) and the lower end face of the cutting part (1).

2. The deep hole drilling bit applicable to MQL cooling according to claim 1, characterized in that, The back angle of the back angle grinding plane (131) is 0.2°.

3. A deep hole drilling bit suitable for MQL cooling according to claim 1, characterized in that, The total width of the main cutting edge band (13) is 0.06 times the tool diameter, and the width of the cutting contact surface (132) is 0.015 times the tool diameter; Or the length of the combined cutting edge band (130) is 1.5 times the tool diameter.

4. A deep hole drilling bit suitable for MQL cooling according to claim 3, characterized in that, The tool diameter is 8 mm, the length of the combined cutting edge band (130) is 12 mm, the total width of the main cutting edge band (13) is 0.48 mm, and the width of the cutting contact surface (132) is 0.12 mm.

5. A deep hole drilling bit suitable for MQL cooling according to claim 1, characterized in that, At the middle of each tool back (11), there is also a secondary cutting edge band (14) that is axially helical and has an arc-shaped end face.

6. A deep hole drilling bit suitable for MQL cooling according to any one of claims 1 to 5, characterized in that, There is also an inverted conical clearance section (4) between the cutting part (1) and the tool shank part (2). The chip flutes (12) and tool backs (11) of the cutting body (10) extend to the end of the clearance section (4). The tool back (11) of the clearance section (4) is a smooth unprocessed surface, and the diameter of the clearance section (4) is lower than the diameter of the cutting body (10).

7. The deep hole drilling bit applicable to MQL cooling according to claim 6, characterized in that, When the tool diameter is greater than or equal to 8 mm, the diameter of the clearance section (4) is 0.3 mm lower than the diameter of the cutting body (10); When the tool diameter is less than 8 mm, the diameter of the clearance section (4) is 0.2 mm lower than the diameter of the cutting body (10).

8. A deep hole drilling bit suitable for MQL cooling according to claim 6, characterized in that, The deep hole drilling bit is also applicable to dry cutting or ordinary cutting scenarios.

9. A deep hole drilling bit suitable for MQL cooling according to claim 6, characterized in that, The deep hole drilling bit is made of a cemented carbide material with an ISO grade of K30-40.

10. A deep hole drilling bit suitable for MQL cooling according to claim 9, characterized in that, The back angle grinding plane (131) is processed by a five-axis grinding machine.

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