A spherical hole-bottom deep-hole drilling device and method

Abstract

The present invention relates to the technical field of deep-hole drilling, and discloses a deep-hole drilling device and method for spherical hole bottoms, including a drill bit; the drill bit includes a tool body, and a connecting thread is provided at the rear of the tool body; a blade is provided at the front end of the tool body, and the front end of the tool body is hemispherical, and the surface of the front end of the tool body is a hemispherical arc surface; the blade includes a first blade, a second blade and a third blade, and they are all arranged radially; and the first blade and the third blade are arranged staggeredly on both sides of the axial direction of the tool body, and the first blade and the second blade are on the same side; the angles formed by the center lines of the first blade, the second blade and the third blade with the axis of the tool body are a°, b°, and c° respectively; and the cutting edges of the blades form an arc required for machining the workpiece; chip-breaking grooves are provided on the blades; a chip removal groove is provided in the tool body, and several guide blocks are provided on the outer side surface of the tool body. The present invention can complete the efficient machining of deep holes with spherical hole bottoms, and has relatively high machining accuracy.

Description

Technical Field

[0001] The present invention relates to the technical field of deep hole drilling, and particularly relates to a deep hole drilling device and method for a spherical hole bottom. Background Art

[0002] Internal chip removal deep hole drills have been widely applied in the fields of national defense industry, machine tools, power generation equipment manufacturing, oil machinery, steel, and various heavy equipment manufacturing.

[0003] With the improvement of current manufacturing requirements, the drilling accuracy required for the processing of many devices is getting higher and higher. In the processing of equipment in special fields such as the national defense field, in addition to the processing of conventional through holes, countersunk holes, etc., deep hole processing, especially the processing of deep holes with special shapes, also accounts for a large proportion in hole processing. For such deep holes with special shapes, such as deep hole blind holes with a spherical hole bottom shape, due to their special shape, chip removal is difficult and it is difficult to guarantee the processing accuracy. Moreover, during the processing of deep holes, the cutting condition of the tool cannot be directly observed, and only work experience (such as listening to the sound during cutting, looking at the chips, etc.) can be relied on to judge whether the cutting process is normal, and the processing difficulty is relatively high. In this process, it is particularly important to maintain high cutting accuracy and guiding accuracy of the tool.

[0004] Conventional internal chip removal deep hole tools, firstly, cannot meet the processing requirements of special hole bottom shapes. Secondly, the cutting accuracy is still easily affected by factors such as hole depth, hole diameter, etc. and the asymmetric structure of the tool itself. During cutting, vibrations, ripples, and tapers are easily generated, and the resultant force of the cutting force is likely to cause deformation of the workpiece, resulting in low cutting accuracy. Moreover, the chip removal effect is poor and the tool durability is low. Summary of the Invention

[0005] The present invention aims to provide a deep hole drilling device and method for a spherical hole bottom, which can efficiently process deep holes with a spherical hole bottom and has relatively high processing accuracy.

[0006] To achieve the above object, the present invention provides the following solutions:

[0007] Solution 1

[0008] A deep hole drilling device for a spherical hole bottom, comprising a drill bit; the drill bit includes a tool body, and a connecting thread is provided at the rear of the tool body; a blade is provided at the front end of the tool body, and the front end of the tool body is hemispherical, and the surface of the front end of the tool body is a hemispherical arc surface;

[0009] The blade includes a first blade, a second blade, and a third blade, and they are all arranged radially; the first blade and the third blade are arranged in a staggered manner on both sides of the axial direction of the tool body, and the first blade and the second blade are on the same side; the angles formed by the center lines of the first blade, the second blade, and the third blade with the axis of the tool body are a°, b°, and c° respectively; and the cutting edges of the blade form an arc required for processing the workpiece;

[0010] Each of the blades is provided with a chip-breaking groove; a chip removal groove is provided inside the tool body, and several guiding blocks arranged along the axis of the tool body are provided on the outer side surface of the tool body.

[0011] Solution Two

[0012] A method for drilling a deep hole with a spherical hole bottom uses a device for drilling a deep hole with a spherical hole bottom as described in Solution One for drilling.

[0013] The working principle and advantages of the present invention are as follows: the front end of the tool body is set as a hemispherical shape, and three blades radially distributed and offset from each other are provided at the front end of the tool body, and the cutting edges of the blades form an arc required for machining the workpiece, which can specifically machine a spherical bottom surface, meet the processing requirements of special deep holes, can efficiently machine special deep holes, and by using blades and tool bodies with different arcs, deep hole parts with spherical hole bottoms of different apertures can be machined.

[0014] The design of multiple blades with different arrangement angles, in addition to being able to complete the cutting task of deep holes with special shapes, each blade can also break the drilling chips of the remaining blades, which is conducive to the discharge of drilling chips, helps to reduce the drilling resistance, and improves the tool life. In particular, in this solution, each blade has its corresponding setting angle, rather than being similar to a conventional tool, only setting a single blade or arranging the blades evenly. The specific blade arrangement in this solution can better adapt to the processing requirements of special spherical hole bottoms, and each blade assists each other to complete the processing of a complete spherical hole bottom with a smooth surface connection, and can achieve a high processing quality. The chip-breaking groove and the chip removal groove can make the chip removal smooth, thereby ensuring the stability of cutting (drilling) and the reliable operation of the tool. And, several guiding blocks are also provided on the tool body in this solution, which can prevent the deep hole drill bit from being eccentric during drilling, and helps to ensure the processing quality of deep holes with special shapes. Description of the Drawings

[0015] Figure 1 It is the three-view drawing of the overall structure of the first embodiment of a device and method for drilling a deep hole with a spherical hole bottom according to the present invention;

[0016] Figure 2 It is the multi-directional schematic diagram of the overall structure of the first embodiment of a device and method for drilling a deep hole with a spherical hole bottom according to the present invention;

[0017] Figure 3 It is the schematic diagram of the structure of the first blade of the first embodiment of a device and method for drilling a deep hole with a spherical hole bottom according to the present invention;

[0018] Figure 4 It is the schematic diagram of the structure of the tool body of the third embodiment of a device and method for drilling a deep hole with a spherical hole bottom according to the present invention;

[0019] Figure 5Schematic diagram I of the cutter body structure of Embodiment 1 of a spherical hole-bottom deep-hole drilling device and method of the present invention;

[0020] Figure 6 Schematic diagram II of the cutter body structure of Embodiment 1 of a spherical hole-bottom deep-hole drilling device and method of the present invention;

[0021] Figure 7 Schematic diagram of the basic guide block structure of Embodiment 1 of a spherical hole-bottom deep-hole drilling device and method of the present invention;

[0022] Figure 8 Schematic diagram of the bakelite guide block structure of Embodiment 1 of a spherical hole-bottom deep-hole drilling device and method of the present invention;

[0023] Figure 9 Schematic diagram of the auxiliary guide block structure of Embodiment 1 of a spherical hole-bottom deep-hole drilling device and method of the present invention. Detailed implementation manners

[0024] The following is a more detailed description through specific implementation manners:

[0025] The markings in the accompanying drawings of the specification include: cutter body 1, front end portion 11 of the cutter body, opening portion 12, solid portion 13, first blade groove 131, second blade groove 132, third blade groove 133, basic guide block installation groove 134, bakelite guide block installation groove 135, auxiliary guide block installation groove 136, chip removal groove 14, first blade 2, second blade 3, third blade 4, chip breaking groove 5, screw hole 51, friction reducing groove 6, basic guide block 7, bakelite guide block 8, auxiliary guide block 9, connecting thread 10.

[0026] Embodiment 1

[0027] The embodiment is basically as shown in the attached Figure 1 、 Figure 2 figures:

[0028] A spherical hole-bottom deep-hole drilling device includes a drill bit; the drill bit includes a cutter body, and a connecting thread 10 is provided at the rear of the cutter body. Specifically, when using this device, the whole device can be connected to the drill pipe through the connecting thread 10, and the length of the drill pipe corresponds to the hole depth to facilitate the completion of deep-hole processing.

[0029] In addition, in this embodiment, a spherical hole-bottom deep hole refers to a hole with a spherical hole bottom surface and a hole depth to aperture ratio L / d≥5. Such holes are prone to the problem that the surface roughness of the hole cannot meet the processing requirements due to poor chip removal; and due to the large hole depth and the special shape of the hole bottom surface, it is very difficult to process and is prone to drilling deviation.

[0030] The front end portion 11 of the tool body is provided with a blade, and the front end portion 11 of the tool body is hemispherical, and the surface of the front end portion 11 of the tool body is a hemispherical arc surface. In this embodiment, the size of the hemispherical arc surface matches the size requirement of the spherical bottom surface of the pre-machined spherical hole bottom deep hole.

[0031] The blades include a first blade 2, a second blade 3 and a third blade 4, and are all arranged radially; the first blade 2 and the third blade 4 are arranged in a staggered manner on both sides of the axis of the tool body 1, and the first blade 2 and the second blade 3 are on the same side; the center lines of the first blade 2, the second blade 3 and the third blade 4 form angles of a°, b°, c° with the axis of the tool body 1 respectively, and the cutting edges of the blades form an arc required for machining the workpiece. Specifically, the value of a is in the range of 80 to 90; the value of b is in the range of 45 to 55; the value of c is in the range of 15 to 25. With such a setting, the installation positions of the three blades are appropriate. Compared with conventional evenly distributed blade and other solutions, in this solution, the cooperation among the three blades is better, and the three blades with different setting angles can comprehensively machine each part of the sphere at the spherical hole bottom, and the spherical arc surface of the machined spherical hole bottom can be guaranteed to be smooth, and the machining effect is better.

[0032] As shown in the Figure 3 attachment, the shapes and structures of the first blade 2, the second blade 3 and the third blade 4 are the same, and they are all indexable cutting blades in the shape of an equilateral triangle, and they overlap each other in the radial direction of the tool body 1, thereby forming an arc required for machining the workpiece. The three sides of the equilateral triangle blade are all arc edges consistent with the arc of the workpiece hole bottom. When the blade is installed, two corners of the blade are correspondingly located on the arc surface required for machining the workpiece, and the other corner of the blade faces the axis of the tool body 1. With such a setting, the blade is adapted to the shape of the hole bottom to be machined, and the jointly formed spherical end portion can specifically complete the machining of the spherical hole bottom deep hole. In this embodiment, the nose radius of the blade is 0.4 mm. And for the pre-machined spherical hole bottom workpiece with a diameter range of 32 to 65 mm, the inscribed circle diameter of the blade can be set to 8.5 mm, 10.5 mm, 12.7 mm, which can effectively ensure the overlap of the blades in the radial direction and ensure that the spherical shape of the workpiece hole bottom can be completely machined by using three blades.

[0033] In addition, the radian of the hemispherical arc surface of the front end portion 11 of the tool body is smaller than the arc required for machining the pre-machined workpiece formed by the blade. With such a setting, it can be ensured that the tool body 1 does not interfere during machining.

[0034] Each of the blades is provided with a chip breaker groove 5; specifically, the chip breaker groove 5 is arranged along the three sides of the equilateral triangle blade. A boss scaled proportionally to the blade shape is provided in the middle of the equilateral triangle blade. The chip breaker groove 5 is located on the side surface of the boss, and the width of the chip breaker groove 5 is 1.6 - 1.9 mm, and the depth of the chip breaker groove 5 is 0.4 - 0.7 mm. A screw hole 51 is opened at the center of the blade, and the blade is stably installed on the tool body 1 through the screw hole 51 in cooperation with a screw. The chips generated during drilling can be broken into shorter chips that are more convenient to discharge through the chip breaker groove 5. Moreover, the chip breaker groove 5 can also guide the chip flow direction and chip shape, so that the chip shape meets the processing requirements and avoids poor chip evacuation.

[0035] Several antifriction grooves 6 are additionally provided on the chip breaker groove 5 in a superimposed manner. Specifically, several antifriction grooves 6 are uniformly arranged in an array along the groove length direction on the chip breaker groove 5. The antifriction grooves 6 can effectively reduce the main cutting force without reducing the durability of the blade and simultaneously improve the chip breaking performance of the blade.

[0036] A chip evacuation groove 14 is provided inside the tool body 1. The tool body 1 is hollow inside, and the hollow part is communicated with the chip evacuation groove 14. Two opposite openings are opened at the front end part 11 of the tool body. The openings are communicated with the chip evacuation groove 14; and the two openings divide the front end part 11 of the tool body into four parts. Specifically, the two openings divide the front end part 11 of the tool body into two opening parts 12 and two solid parts 13; the blade is arranged on the solid part 13. First blade grooves 131, second blade grooves 132 and third blade grooves 133 for installing the first blade 2, the second blade 3 and the third blade 4 are respectively provided on the solid part 13; the bottom surface of the first blade groove 131 is parallel to the bottom surface of the third blade groove 133 and the distance therebetween is equal to twice the blade thickness. The shape of the installation groove is consistent with the shape of the blade. Screw holes corresponding to the screw holes 51 of the blade are also provided at the installation groove for fixing the blade.

[0037] Several guiding blocks are provided on the outer side surface of the tool body 1 along the axis of the tool body 1. The guiding blocks include a basic guiding block 7, a bakelite guiding block 8 and an auxiliary guiding block 9. Specifically, as shown in the attached... Figure 5 、 Figure 6 As shown in the attached... Figure 7 、 Figure 8 、 Figure 9 As shown in the attached...

[0038] There are two base guiding blocks 7 arranged around the axis of the tool body 1. There are three bakelite guiding blocks 8 arranged around the axis of the tool body, and two of the bakelite guiding blocks 8 are coaxial with the base guiding blocks 7. The auxiliary guiding block 9 is arranged on the front side of the bakelite guiding block 8 that is not coaxial with the base guiding block 7.

[0039] This embodiment also provides a method for drilling deep holes with a spherical hole bottom, using a device for drilling deep holes with a spherical hole bottom as described above for drilling.

[0040] For the device and method for drilling deep holes with a spherical hole bottom provided in this embodiment, the shape of the front end portion 11 of the tool body is special. With three specially installed cutting blades, it can complete the efficient processing of deep holes with a spherical hole bottom, and the processing accuracy is relatively high. In this solution, the design of multiple cutting blades with different arrangement angles can specifically complete the cutting tasks of deep holes with special shapes, and can also break the drilling chips of the remaining blades, which helps to discharge the drilling chips.

[0041] Moreover, compared with the conventional solution, the processing tools provided by the conventional solution often use general cutting blades, and the shape of the cutting blades does not match the special spherical hole bottom shape. Although it can also complete the processing of the spherical hole bottom, the processing error is relatively large, and additional finishing processes need to be arranged for processing again to reduce the error. In this solution, the shape of the cutting blade is consistent with the arc required for the pre-processed workpiece, the processing error is very small, it can achieve a relatively high processing accuracy, and can be used for finishing or semi-finishing.

[0042] Furthermore, the design of the chip-breaking groove 5 and the friction-reducing groove 6 on the cutting blade can better guide the shape and direction of chip breaking, and then ensure smooth chip discharge, and the chip shape meets the requirements. In addition, in this solution, several different types of guiding blocks are provided and are respectively distributed at different positions of the tool body 1, which can guide in all directions, effectively correct the tool deflection, achieve a relatively high guiding accuracy, effectively prevent the hole from deflecting, help to ensure the drilling accuracy and surface finish, and improve the tool life.

[0043] Embodiment 2

[0044] A device for drilling deep holes with a spherical hole bottom, different from Embodiment 1 in that: in this embodiment, the angles formed by the center lines of the first cutting blade 2, the second cutting blade 3, and the third cutting blade 4 with the axis of the tool body 1 are 85°, 50°, and 20° respectively.

[0045] For the device for drilling deep holes with a spherical hole bottom provided in this embodiment, compared with Embodiment 1, the setting angles of the three cutting blades here are the best and can achieve a relatively high cutting accuracy.

[0046] Embodiment 3

[0047] A spherical hole-bottom deep-hole drilling device, based on Embodiment 1, has adjusted the structure of the tool body 1.

[0048] As shown in the Figure 4 attachment, the connecting thread 10 at the rear of the tool body 1 is a square thread, and a double positioning platform is also provided at the rear of the tool body 1 to ensure the connection accuracy.

[0049] For the spherical hole-bottom deep-hole drilling device provided in this embodiment, compared with Embodiment 1, the positioning platform can serve as a stop portion, and thus can better position the tool body 1, which helps to further improve the machining accuracy of the tool.

[0050] Embodiment 4

[0051] A spherical hole-bottom deep-hole drilling device, which is different from Embodiment 1 in that: in this embodiment, the chip-breaking grooves 5 are arranged along the three sides of the equilateral triangular blade, and 6 friction-reducing grooves 6 are evenly arranged at the chip-breaking grooves 5 corresponding to each side of the triangular blade.

[0052] With such a setting, the number and arrangement of the friction-reducing grooves 6 are appropriate, which can reduce the main cutting force to the greatest extent and improve the chip-breaking performance of the blade without affecting the performance of the chip-breaking grooves 5. Specifically, when the feed rate of the tool is large, the chip thickness and stiffness increase and it is not easy to bend, the contact stress between the chip and the bottom of the chip-breaking groove 5 is very large and in an adhesive contact state. At this time, the friction-reducing grooves 6 at the bottom of the groove can effectively reduce the contact area, so that the friction between the chip and the bottom of the groove is reduced, thereby effectively reducing the main cutting force. At the same time, the friction-reducing grooves 6 can assist the chip-breaking grooves 5 to control the shape, size, etc. of the chip, and thus effectively improve the chip-breaking performance.

[0053] Embodiment 5

[0054] A spherical hole-bottom deep-hole drilling device, which is different from Embodiment 1 in that: in this embodiment, the top surface of the basic guide block 7 is flush with the bottom surface of the front end of the hemispherical tool body 11. Three bakelite guide blocks 8 are evenly distributed on the outer side surface of the tool body 1 around the axis of the tool body 1. And the bakelite guide block 8 coaxial with the basic guide block 7 is located behind the basic guide block 7, and this bakelite guide block 8 is approximately located at the 1 / 2 position of the whole tool body 1 and the connecting thread 10 (based on the axis of the threaded hole at the center of the bakelite guide block 8).

[0055] The auxiliary guide block 9 is arranged on the front side of the bakelite guide block 8 that is not coaxial with the basic guide block 7, and the auxiliary guide block 9 is used to better protect the tool body and guide.

[0056] In this embodiment, the position arrangement of each guide block is more appropriate, and through the cooperation of the three types of guide blocks, a comprehensive and accurate guiding effect can be achieved, which helps to further improve the guiding accuracy and thus improve the machining accuracy.

[0057] The above are only embodiments of the present invention. Specific structures and characteristics and other common knowledge in the art are not described in detail herein. Those of ordinary skill in the art know all the common general technical knowledge in the technical field to which the invention pertains before the filing date or the priority date, are able to learn all the prior art in this field, and have the ability to apply the conventional experimental means before this date. Those of ordinary skill in the art can, under the inspiration given in this application, combine their own abilities to complete and implement this solution. Some typical well-known structures or well-known methods should not become obstacles for those of ordinary skill in the art to implement this application. It should be noted that for those skilled in the art, without departing from the structure of the present invention, several deformations and improvements can also be made, and these should also be regarded as the protection scope of the present invention, and these will not affect the implementation effect of the present invention and the practicality of the patent.

Claims

1. A spherical hole bottom deep hole drilling device, comprising a drill bit; the drill bit includes a cutter body, and a connecting thread is provided at the rear of the cutter body; characterized in that, A blade is provided at the front end of the tool body, and the front end of the tool body is hemispherical, and the surface of the front end of the tool body is a hemispherical arc surface; The blade includes a first blade, a second blade and a third blade, all of which are arranged radially; the first blade and the third blade are arranged offset on both sides of the axial direction of the tool body, and the first blade and the second blade are on the same side; the central lines of the first blade, the second blade and the third blade form angles of a°, b°, and c° with the axis of the tool body respectively; and the cutting edges of the blades form an arc required for machining the workpiece; the value of a is in the range of 80-90; the value of b is in the range of 45-55; the value of c is in the range of 15-25; Chip-breaking grooves are provided on each blade; a chip evacuation groove is provided in the tool body, and several guide blocks are provided on the outer side surface of the tool body along the axis of the tool body; Each blade overlaps in the radial direction; when using this device, the whole device is connected to the drill pipe through a connecting thread, and the length of the drill pipe corresponds to the hole depth, so as to facilitate the deep hole machining of the spherical hole bottom; the deep hole of the spherical hole bottom refers to: a hole with a spherical bottom surface and a hole depth to hole diameter ratio L / d≥5; the size of the hemispherical arc surface matches the size requirements of the spherical bottom surface of the pre-machined deep hole of the spherical hole bottom.

2. The deep-hole drilling device for spherical hole bottoms according to claim 1, characterized in that, Two opposite openings are provided at the front end of the tool body, and the openings communicate with the chip evacuation groove; and the two openings divide the front end of the tool body into two opening parts and two solid parts; the blade is provided on the solid part.

3. A spherical hole bottom deep hole drilling device according to claim 2, characterized in that, First blade grooves, second blade grooves and third blade grooves for installing the first blade, the second blade and the third blade are respectively provided on the solid parts; the bottom surfaces of the first blade groove and the third blade groove are parallel and the distance therebetween is equal to twice the thickness of the blade.

4. A spherical hole bottom deep hole drilling device according to claim 1, characterized in that, Several anti-friction grooves are additionally provided on the chip-breaking groove.

5. The spherical hole bottom deep hole drilling device according to claim 4, characterized in that, The width of the chip-breaking groove is 1.6-1.9 mm, and the depth of the chip-breaking groove is 0.4-0.7 mm.

6. The deep-hole drilling device for spherical hole bottom according to claim 1, characterized in that The guide block includes a basic guide block; there are two basic guide blocks arranged around the axis of the tool body.

7. The deep-hole drilling device for spherical hole bottom according to claim 6, characterized in that, The guide block further includes a bakelite guide block; there are three bakelite guide blocks arranged around the axis of the tool body, and two of the bakelite guide blocks are coaxial with the basic guide block.

8. A spherical hole bottom deep hole drilling device according to claim 7, characterized in that, The guide block further includes an auxiliary guide block; the auxiliary guide block is provided on the front side of the bakelite guide block that is not coaxial with the basic guide block.

9. A method for deep-hole drilling with a spherical hole bottom, characterized in that, Drilling is carried out by using a deep hole drilling device for the spherical hole bottom as described in any one of claims 1-8.

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