A high-rigidity horizontal numerical control milling machine for machining helical groove of drill bit

Abstract

The application discloses a high-rigidity horizontal numerical control milling machine for machining of a drill bit helical groove, and belongs to the technical field of mine drilling tool machining equipment. A fixed base and a moving base are arranged on a base, a tail clamping part is arranged at the fixed base, a head clamping part is arranged at the moving base, a limiting part is arranged outside the tail clamping part, a guide groove is arranged on a limiting frame for feeding and machining of a milling cutter body, a guide body at the lower part of the limiting frame is arranged at the outlet end of the spline groove and extends along the spiral chip removal groove, a first guide plate and a second guide plate are arranged at the end of the limiting frame, a pressing part is arranged outside the first guide plate, after machining of one spline groove is completed, the pressing part presses the first guide plate to the end part of the guide body, the first guide groove is connected with the extension direction of the guide body, the milling cutter is used to machine the spiral chip removal groove and the tooth pocket based on the spline groove, and a chip removal channel is formed between the first guide plate and the guide body, so that machining of the spline, the spiral chip removal groove and the tooth pocket is sequentially completed through one-time clamping.

Description

Technical Field

[0001] This invention relates to the field of mining drill bit processing equipment technology, specifically a high-rigidity horizontal CNC milling machine for machining drill bit spiral grooves. Background Technology

[0002] Down-the-hole (DH) drill bits are used in conjunction with down-the-hole hammers, engaging with the hammer via splines for drilling operations. DH drill bits are widely used in open-pit mining, water well drilling, tunnel construction, quarrying, hydropower projects, and other construction fields, offering advantages such as deep and straight drilling, large hole diameter, and high drilling efficiency. The end face design of DH drill bits mainly includes convex, flat, concave, and center-recessed types. Carbide teeth are often arranged using ball teeth, spring teeth, or a combination of both. The structure of a DH drill bit is relatively complex. Its tail end has an external spline that mates with the hammer, and the head end face is inlaid with carbide tooth recesses. The head also features a spiral chip removal groove to remove rock cuttings generated during drilling. The spiral chip removal groove needs to maintain a precise relative position with the spline groove in the circumferential direction to ensure unobstructed chip removal channels.

[0003] Currently, the splines, helical chip flutes, and tooth sockets of down-the-hole drill bits typically need to be machined separately in different processes. Each process requires reclamping and positioning the workpiece. Specifically, the tail spline is first machined on one machine tool, then the workpiece is disassembled and transferred to another machine tool for reclamping and alignment. Next, the helical chip flutes on the head are machined. Finally, it needs to be transferred again to a third process for machining the end face tooth sockets. Because the splines, helical chip flutes, and tooth sockets are machined independently in multiple processes, each process uses the outer circle or end face of the drill bit blank as a positioning reference for reclamping. The outer circle of the drill bit blank is a rough surface, and its size and shape have large machining allowance deviations. The positioning datum used in different processes is not uniform, and the positioning errors generated during multiple clamping processes accumulate one after another. This makes it difficult to accurately guarantee the angular positional relationship between the machined spline and the helical chip removal groove, as well as between the spline and the tooth socket. This affects the smoothness of the powder removal channel when the down-the-hole drill bit is engaged with the impactor, thereby reducing drilling efficiency and service life. In addition, multiple clamping also significantly increases auxiliary time and reduces production efficiency, making it difficult to meet the needs of large-scale mass production. Therefore, there is an urgent need to provide a horizontal CNC milling machine that can sequentially complete the spline, helical chip removal groove, and tooth socket in a single clamping, fundamentally eliminating the problem of positioning error accumulation caused by multiple clamping. Therefore, we propose a high-rigidity horizontal CNC milling machine for machining helical grooves in drill bits. Summary of the Invention

[0004] The purpose of this invention is to provide a high-rigidity horizontal CNC milling machine for machining helical grooves in drill bits, so as to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a high-rigidity horizontal CNC milling machine for machining spiral grooves in drill bits, comprising a milling machine outer machine, a base inside the milling machine outer machine, a slide plate above the base, a tool holder plate on the slide plate, a milling cutter body mounted on the tool holder plate, a three-dimensional adjustment component inside the milling machine outer machine for adjusting the position of the milling cutter body in three-dimensional coordinates, a fixed seat and a movable seat on the base, a tail clamping component for clamping the tail of the drill bit blank at the fixed seat, and a head clamping component for clamping the head of the drill bit blank at the movable seat, and a movable component installed on the outside of the base for driving the movable seat so that the drill bit blank is clamped between the tail clamping component and the head clamping component; A limiting component is installed on the outside of the tail clamping component. The limiting component includes a limiting frame located above the outer spline of the drill bit blank. The limiting frame has a guide groove adapted to the cross-section of the spline groove. The milling cutter body feeds along the guide groove to machine the spline groove on the surface of the drill bit blank. A guide body is provided at the lower part of the limiting frame. The guide body is located at the outlet end of the spline groove. The starting end of the guide body is connected to the end of the spline groove. The end of the guide body fits against the drill bit neck and extends along the predetermined direction of the spiral chip removal groove. A first guide plate is installed at the end of the limiting frame. The first guide plate has a feature for guiding the milling cutter to machine the spline groove. The first guide groove of the spiral chip removal groove is provided. A second guide plate is installed on the outer side of the first guide plate. The second guide plate has a second guide groove for guiding the milling cutter to process the drill tooth cavity. A pressing member is installed on the outer side of the first guide plate. After one spline groove is processed, the pressing member presses the first guide plate down to the end of the guide body, so that the first guide groove is aligned with the extension direction of the guide body. The milling cutter is guided to process the spiral chip removal groove along the first guide groove with the processed spline groove as a reference, and to process the drill tooth cavity along the second guide groove. At the same time, the first guide plate and the guide body form a chip removal channel.

[0006] Preferably, both the bottom of the first guide plate and the second guide plate are provided with arc-shaped grooves, the curvature of which is adapted to the curvature of the outer circle of the drill bit neck, the length of the second guide plate is shorter than the length of the first guide plate, and the second guide plate is disposed on the upper outer side of the first guide plate.

[0007] Preferably, the head clamping component includes an indexing drive motor mounted on a movable base. A first chuck is mounted on the output end of the indexing drive motor. An intermediate shaft is clamped in the middle of the first chuck. A locking plate is mounted on the end of the intermediate shaft. The inner side of the locking plate is a crown arc-shaped rotating end face that is adapted to the end face of the drill bit head. A slot is provided on the crown arc-shaped rotating end face for the drill bit head protrusion to pass through.

[0008] Preferably, the crown arc-shaped rotating end face is also provided with a positioning post, the position of which corresponds to the position of the air outlet hole on the drill bit end face. The positioning post is inserted into the air outlet hole on the drill bit end face to achieve angular positioning. The intermediate shaft is also equipped with an indexing plate, on which angle scale lines are engraved. The indexing drive motor drives the intermediate shaft to rotate a predetermined angle according to the scale of the indexing plate.

[0009] Preferably, the movable component includes a movable motor mounted on the outside of the base, the output shaft of the movable motor is connected to a first threaded rod, a threaded sleeve is fixed on the movable seat, the threaded sleeve is threadedly engaged with the first threaded rod, the base is also provided with a guide rail, the movable seat is slidably mounted on the guide rail, when the movable motor drives the first threaded rod to rotate, the threaded sleeve drives the movable seat to move linearly along the guide rail.

[0010] Preferably, the tail clamping component includes a second clamping plate mounted on a fixed base. The second clamping plate is used to clamp the clamping sleeve at the tail of the drill bit blank. The clamping sleeve is provided with a positioning insertion post that is inserted into the center hole of the drill bit tail. A rotating motor is mounted outside the base. The output shaft of the rotating motor is connected to the rotating shaft of the second clamping plate through a belt drive. The rotating motor drives the second clamping plate to rotate the clamping sleeve and the drill bit blank at indexing intervals.

[0011] Preferably, the limiting component further includes a fixing ring fixed to the outside of the clamping sleeve, a support plate is installed on the fixing ring, a hinge plate is fixed to one end of the limiting frame, the support plate and the hinge plate are hinged together by a hinge shaft, and a locking nut is provided at the hinge to adjust and lock the hinge angle. A tension spring is connected between the support plate and the hinge plate, and the tension spring provides tension to deflect the limiting frame toward the drill bit blank. After the guide body fits against the drill bit neck, the tension of the tension spring keeps the guide body in a fitted state with the drill bit neck.

[0012] Preferably, the pressing component includes a clamping plate fixed to the side of the first guide plate, a push-pull column fixed on the clamping plate, an electromagnetic plate fixed to the top of the push-pull column, a metal plate fixed to the outside of the limiting frame, a slot on the metal plate, the clamping plate being slidably disposed in the slot, two magnetic suction columns on the bottom surface of the electromagnetic plate, and adsorption holes corresponding to the positions of the magnetic suction columns on the metal plate, a support spring between the electromagnetic plate and the metal plate. After the spline groove is processed, the electromagnetic plate is energized to generate magnetic attraction, the magnetic suction columns are drawn into the adsorption holes, the magnetic attraction overcomes the elastic force of the support spring, causing the push-pull column to drive the clamping plate to slide downward along the slot, and the first guide plate moves down to the position where it docks with the end of the guide body.

[0013] Preferably, the width of the limiting frame is greater than the width of the spline groove, and a track plate is fixed to the end of the limiting frame. A vertically extending guide rail is provided on the track plate, and a slider is fixed to the outside of the first guide plate. The slider slides on the guide rail.

[0014] Preferably, a cooling pipe is installed on the tool holder plate, and multiple cooling nozzles are provided on the cooling pipe. Multiple through holes corresponding to the positions of the cooling nozzles are opened on the side wall of the limiting frame. The cooling nozzles extend into the through holes and spray coolant into the processing area inside the limiting frame.

[0015] Compared with the prior art, the beneficial effects of the present invention are: This invention provides a limiting frame outside the tail clamping component, with a guide groove on the limiting frame that matches the cross-section of the spline groove. The milling cutter body feeds along the guide groove to process the spline groove, so that the machining accuracy of the spline groove is directly guaranteed by the accuracy of the guide groove. At the same time, the width of the limiting frame is greater than the width of the spline groove, providing sufficient overtravel space for the milling cutter body and ensuring that the spline groove is machined completely along its entire length. This invention provides a guide body at the spline groove outlet and a first guide plate and a second guide plate at the end of a limiting frame. After machining one spline groove, a pressing component presses the first guide plate down to align with the end of the guide body, connecting the first guide groove with the extension direction of the guide body to form a continuous guide path. The milling cutter uses the pre-machined spline groove as a reference to machine a spiral chip removal groove along the first guide groove and a tooth socket along the second guide groove. Since each spiral chip removal groove and each tooth socket uses the corresponding pre-machined spline groove as a machining reference, and the drill bit blank does not need to be disassembled during the entire machining process, the accumulation of positioning errors caused by multiple clamping is completely eliminated, ensuring the angular positional accuracy between the spline, spiral chip removal groove, and tooth socket. This invention incorporates an electromagnetic plate within the pressing component. When energized, the electromagnetic plate generates magnetic attraction, overcoming the elastic force of the supporting spring. This causes the push-pull column to drive the clamping plate downwards along the clamping groove. Consequently, the first guide plate moves downwards to a position where it aligns with the end of the guide body. Simultaneously, the first guide plate and the guide body enclose a chip removal channel. This chip removal channel provides a smooth discharge path for chips during the machining process of the spiral chip removal groove, preventing chip accumulation in the machining area and improving the surface finish and tool life. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of the milling machine's outer machine compartment door in the closed state. Figure 2 This is a schematic diagram of the overall structure of the present invention; Figure 3 This is a schematic diagram of the side structure of the present invention; Figure 4 This is a schematic diagram of the present invention after the base has been removed; Figure 5 This is a schematic diagram of the structure of the tool holder support plate of the present invention; Figure 6 This is a schematic diagram of the tail clamping component and head clamping component of the present invention in the state of separation from the drill bit; Figure 7This is a schematic diagram of the structure of the head clamping component of the present invention; Figure 8 This is a schematic diagram of the tail clamping component and the limiting component of the present invention; Figure 9 This is a schematic diagram of the pressing component, the first guide plate, and the second guide plate of the present invention; Figure 10 This is a partial structural diagram of the limiting frame of the present invention.

[0017] In the diagram: 1. Milling machine outer frame; 2. Tail clamping component; 3. Head clamping component; 4. Moving component; 5. Limiting component; 6. Guide body; 7. First guide plate; 8. Second guide plate; 9. Pressing component; 11. Base; 12. Slide plate; 13. Tool holder support plate; 14. Milling cutter body; 15. Fixed seat; 16. Moving seat; 17. Guide slide rail; 18. Cooling pipe; 19. Cooling spray; 21. Second chuck; 22. Clamping sleeve; 23. Positioning insertion post; 24. Rotary motor; 31. Indexing drive motor; 32. First chuck; 33. Intermediate shaft; 34. Clamping plate; 35. Crown arc-shaped rotating end face; 36. Slot; 37. Positioning post; 38. Indexing plate; 41. Moving motor; 42. First threaded rod; 43. Threaded sleeve; 51. Limiting frame; 52. Fixing ring; 53. Support plate; 54. Hinge plate; 55. Tension spring; 71. First guide groove; 72. Arc-shaped groove; 73. Track plate; 74. Slider; 81. Second guide groove; 91. Clamping plate; 92. Push-pull post; 93. Electromagnetic plate; 94. Metal plate; 95. Slot; 96. Magnetic suction post; 97. Adsorption hole; 98. Support spring. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] This invention provides a technical solution: a high-rigidity horizontal CNC milling machine for machining spiral grooves in drill bits. The milling machine outer unit 1 constitutes the external protective structure of the entire horizontal CNC milling machine. The interior of the milling machine outer unit 1 is a hollow structure, within which a base 11 is installed. The base 11 is fixedly installed inside the milling machine outer unit 1. A slide plate 12 is installed above the base 11. An X-axis drive component is installed between the slide plate 12 and the base 11. The X-axis drive component includes an X-axis drive motor installed outside the base 11. The output shaft of the X-axis drive motor is connected to an X-axis threaded rod. An X-axis threaded sleeve is fixed to the bottom of the slide plate 12, and the X-axis threaded sleeve is threadedly engaged with the X-axis threaded rod. An X-axis guide rail is also provided on the base 11, and the slide plate 12 is slidably mounted on the X-axis guide rail. When the motor drives the X-axis threaded rod to rotate, the X-axis threaded sleeve drives the slide plate 12 to move linearly along the X-axis guide rail, thereby realizing the position adjustment of the milling cutter body 14 in the X direction. The slide plate 12 is provided with a Y-axis driving component. The slide plate 12 has an installation groove inside, and a Y-axis driving motor is fixedly installed in the installation groove. The output shaft of the Y-axis driving motor is connected to the Y-axis threaded rod. A Y-axis guide rail is also fixedly installed on the slide plate 12. The tool holder plate 13 is slidably set on the Y-axis guide rail. A Y-axis threaded sleeve is fixed at the bottom of the tool holder plate 13. The Y-axis threaded sleeve is threadedly engaged with the Y-axis threaded rod. When the Y-axis driving motor drives the Y-axis threaded rod to rotate, the Y-axis threaded sleeve drives the tool holder plate 13 to move linearly along the Y-axis guide rail, thereby realizing the position adjustment of the milling cutter body 14 in the Y direction.

[0020] The tool holder plate 13 is equipped with a Z-axis drive component and a mounting base. The Z-axis drive component includes a Z-axis drive motor fixedly mounted on the tool holder plate 13. The output shaft of the Z-axis drive motor is connected to a Z-axis threaded rod. A Z-axis threaded sleeve is fixed on the mounting base, and the Z-axis threaded sleeve is threadedly engaged with the Z-axis threaded rod. The tool holder plate 13 is also equipped with a Z-axis guide rail, and the mounting base is slidably mounted on the Z-axis guide rail. When the Z-axis drive motor drives the Z-axis threaded rod to rotate, the Z-axis threaded sleeve drives the mounting base to move linearly along the Z-axis guide rail, thereby realizing the position adjustment of the milling cutter body 14 in the Z direction. A spindle motor is also fixedly mounted on the mounting base. The output shaft of the spindle motor is fixedly connected to the tool holder of the milling cutter body 14. The spindle motor drives the milling cutter body 14 to rotate around its own axis to realize the cutting motion. The X-axis drive motor, Y-axis drive motor, Z-axis drive motor and spindle motor together constitute a three-dimensional adjustment component. This three-dimensional adjustment component can adjust the milling cutter body 14 to any machining position in the three-dimensional coordinate system to ensure that the milling cutter body 14 is accurately aligned with the feature part to be machined on the drill blank.

[0021] A fixed seat 15 is fixedly installed on the base 11, and a movable seat 16 is slidably arranged on the base 11. The fixed seat 15 and the movable seat 16 are arranged opposite each other along the longitudinal centerline of the base 11. A tail clamping component 2 is installed at the fixed seat 15 for clamping the tail of the drill bit blank. A head clamping component 3 is installed at the movable seat 16 for clamping the head of the drill bit blank. A movable component 4 is installed on the outside of the base 11 for driving the movable seat 16 to reciprocate along the longitudinal direction of the base 11. The movable component 4 includes a movable motor 41 fixedly installed on the outside of the base 11. The output shaft of the movable motor 41 is fixedly connected to a first threaded rod 42, which reciprocates along the longitudinal direction of the base 11. Extending outwards, a threaded sleeve 43 is fixedly installed on the movable seat 16. The threaded sleeve 43 is sleeved on the outside of the first threaded rod 42 and threadedly engaged with the first threaded rod 42. A guide slide rail 17 is also fixedly installed on the base 11. The guide slide rail 17 extends along the longitudinal direction of the base 11. The movable seat 16 is slidably mounted on the guide slide rail 17. When the movable motor 41 drives the first threaded rod 42 to rotate, the threaded sleeve 43 drives the movable seat 16 to move linearly along the guide slide rail 17, thereby adjusting the axial distance between the movable seat 16 and the fixed seat 15 to accommodate drill bit blanks of different lengths. The two ends of the drill bit blank are clamped by the tail clamping component 2 and the head clamping component 3, respectively, so that the drill bit blank is in a stable clamping state on the horizontal CNC milling machine.

[0022] The tail clamping component 2 includes a second chuck 21 fixedly mounted on the fixed base 15. The second chuck 21 is a three-jaw or four-jaw chuck structure. The rotation center line of the second chuck 21 coincides with the longitudinal center line of the base 11. A clamping sleeve 22 is clamped at the center of the second chuck 21. The clamping sleeve 22 is a cylindrical structure. The inner diameter of the clamping sleeve 22 is adapted to the outer diameter of the tail of the drill bit blank. A positioning insertion post 23 is fixedly installed inside the clamping sleeve 22. The positioning insertion post 23 is arranged along the axial center line of the clamping sleeve 22. The outer diameter of the positioning insertion post 23 is adapted to the inner diameter of the central hole of the tail of the drill bit blank. The positioning insertion post 23 is inserted into the central hole of the tail of the drill bit blank to achieve clamping of the drill bit blank. The tail end is axially positioned, and the outer wall of the clamping sleeve 22 is clamped by the claws of the second chuck 21 to achieve radial clamping of the tail end of the drill bit blank. A rotary motor 24 is also fixedly installed on the outside of the base 11. The output shaft of the rotary motor 24 is connected to the rotating shaft of the second chuck 21 by belt drive. A drive pulley is installed on the output shaft of the rotary motor 24, and a driven pulley is installed on the rotating shaft of the second chuck 21. The belt is wound between the drive pulley and the driven pulley. When the rotary motor 24 starts, it drives the rotating shaft of the second chuck 21 to rotate through the belt. The second chuck 21 drives the clamping sleeve 22 and the clamped drill bit blank to rotate around its own axis, thereby realizing the indexing rotation of the drill bit blank.

[0023] The head clamping component 3 includes an indexing drive motor 31 fixedly mounted on the movable base 16. A first chuck 32 is mounted at the output end of the indexing drive motor 31. The first chuck 32 is a three-jaw or four-jaw chuck structure. The rotation center line of the first chuck 32 coincides with the rotation center line of the second chuck 21. An intermediate shaft 33 is clamped at the center of the first chuck 32. The intermediate shaft 33 is a rod-shaped structure extending along the longitudinal direction of the base 11. A locking plate 34 is fixedly mounted at the end of the intermediate shaft 33. The locking plate 34 is a plate-shaped structure. The inner surface of plate 34 is a crown-shaped curved rotating end face 35. The curvature of the crown-shaped curved rotating end face 35 matches the curvature of the drill bit head end face. The crown-shaped curved rotating end face 35 fits against the end face of the drill bit head. A slot 36 is formed on the crown-shaped curved rotating end face 35. The position and shape of the slot 36 correspond to the protrusion on the end face of the drill bit head. The protrusion on the end face of the drill bit head passes through the slot 36, thereby precisely engaging the locking plate 34 with the end face of the drill bit head. A positioning post 37 is also fixedly installed on the crown-shaped curved rotating end face 35. The position of the positioning post 37 is aligned with the drill bit head end face. The air outlets on the head end face are positioned correspondingly, and the outer diameter of the positioning pin 37 is matched with the inner diameter of the air outlet on the drill bit head end face. The positioning pin 37 is inserted into the air outlet on the drill bit head end face to achieve angular positioning of the drill bit head relative to the clamping plate 34. An indexing plate 38 is also fixedly installed on the intermediate shaft 33. The indexing plate 38 has a disc-shaped structure, and angle scale lines are engraved on the circumference of the indexing plate 38. The indexing plate 38 rotates synchronously with the intermediate shaft 33. When the indexing drive motor 31 drives the intermediate shaft 33 to rotate, the intermediate shaft 33 drives the clamping plate 34 and the drill bit head to rotate synchronously. The rotation and indexing drive motor 31 controls the rotation angle of the intermediate shaft 33 according to the angle scale lines on the indexing plate 38, thereby realizing the precise indexing of the drill bit blank. The rotation motor 24 of the tail clamping component 2 and the indexing drive motor 31 of the head clamping component 3 work together to realize the indexing rotation of the drill bit blank around its own axis. During the processing, one end of the drill bit blank is clamped by the tail clamping component 2 and the other end is clamped by the head clamping component 3, forming a double-end support clamping method, which improves the rigidity and stability of the drill bit blank during the processing.

[0024] A limiting component 5 is installed on the outside of the tail clamping component 2. The limiting component 5 is used to guide and limit the feed path of the milling cutter body 14 during machining. The limiting component 5 includes a limiting frame 51, which is set above the outer spline of the drill bit blank. The limiting frame 51 is a frame structure with a hollow cavity inside. A guide groove is provided on the limiting frame 51, which penetrates the upper and lower walls of the limiting frame 51. The cross-sectional shape of the guide groove matches the cross-sectional shape of the spline groove. When the milling cutter body 14 feeds along the guide groove, the guide groove constrains the movement direction of the milling cutter body 14, so that the milling cutter body 14 machines a spline groove of a predetermined shape and position on the surface of the drill bit blank. The width of the limiting frame 51 is greater than the width of the spline groove. The design of the limiting frame 51 being wider than the spline groove allows the limiting frame 51 to cover the entire processing area of ​​the spline groove and provides sufficient operating space for the feed of the milling cutter body 14. The clamping sleeve 22 has an outer fixing ring 52, on which a support plate 53 is installed. One end of the limiting frame 51 is fixed with a hinge plate 54. The support plate 53 and the hinge plate 54 are hinged together by a hinge shaft, and a locking nut is provided at the hinge to adjust and lock the hinge angle. A tension spring 55 is connected between the support plate 53 and the hinge plate 54. The tension spring 55 provides tension to deflect the limiting frame 51 toward the drill bit blank. After the guide body 6 is in contact with the drill bit neck, the tension of the tension spring 55 keeps the guide body 6 in contact with the drill bit neck.

[0025] The lower part of the limiting frame 51 is provided with a guide body 6, which is an arc-shaped plate structure. The guide body 6 is located at the outlet end of the spline groove. The starting end of the guide body 6 is connected to the end of the spline groove, and the end of the guide body 6 extends along the preset direction of the spiral chip removal groove. The end of the guide body 6 is attached to the outer circular surface of the drill neck. The side of the guide body 6 that is in contact with the drill neck is an arc surface. The curvature of the arc surface is adapted to the curvature of the outer circle of the drill neck. The arc surface is tightly attached to the outer circular surface of the drill neck. The surface of the arc surface is sprayed with a wear-resistant coating. The wear-resistant coating is selected from either titanium nitride coating or aluminum titanium nitride coating. The wear-resistant coating can significantly improve the wear resistance of the contact surface between the guide body 6 and the drill neck, extend the service life of the guide body 6, and also reduce the frictional resistance between the guide body 6 and the drill neck, avoiding damage to the surface quality of the drill neck due to high temperature generated by friction during processing.

[0026] A first guide plate 7 is installed at the end of the limiting frame 51. The first guide plate 7 is a plate-shaped structure and is located at the end of the limiting frame 51, extending vertically. A first guide groove 71 is formed on the first guide plate 7, and the extension direction of the first guide groove 71 is consistent with the direction of the spiral chip removal groove. The first guide groove 71 is used to guide the milling cutter to process the spiral chip removal groove. A second guide plate 8 is installed on the outside of the first guide plate 7. The second guide plate 8 is a plate-shaped structure and is located outside and above the first guide plate 7. The length of the second guide plate 8 is shorter than the length of the first guide plate 7. A second guide groove is formed on the second guide plate 8. 81. The extension direction of the second guide groove 81 is consistent with the arrangement direction of the drill tooth socket. The second guide groove 81 is used to guide the milling cutter to process the drill tooth socket. The bottom of the first guide plate 7 is provided with an arc groove 72, and the bottom of the second guide plate 8 is also provided with an arc groove 72. The curvature of the arc groove 72 at the bottom of the first guide plate 7 matches the curvature of the outer circle of the drill neck. The curvature of the arc groove 72 at the bottom of the second guide plate 8 also matches the curvature of the outer circle of the drill neck. When the first guide plate 7 and the second guide plate 8 are in the pressing state, the arc groove 72 fits against the outer circle surface of the drill neck, thereby accurately limiting the final pressing position of the first guide plate 7 and the second guide plate 8.

[0027] A pressing member 9 is installed on the outer side of the first guide plate 7. The pressing member 9 is used to drive the first guide plate 7 and the second guide plate 8 to move downward. The pressing member 9 includes a clamping plate 91, a push-pull column 92, an electromagnetic plate 93, a metal plate 94, and a support spring 98. The clamping plate 91 is fixedly installed on the side of the first guide plate 7. The clamping plate 91 is a plate-shaped structure and extends outward in the horizontal direction. The push-pull column 92 is fixedly installed on the upper surface of the clamping plate 91. The push-pull column 92 is a column-shaped structure and extends in the vertical direction. The top of the push-pull column 92... An electromagnetic plate 93 is fixedly installed on the part. The electromagnetic plate 93 has a flat structure and is manufactured using existing electromagnet technology. An excitation coil is wound inside the electromagnetic plate 93. When the excitation coil is energized, the electromagnetic plate 93 generates a magnetic attraction force. When the excitation coil is de-energized, the magnetic attraction force of the electromagnetic plate 93 disappears. Two magnetic attraction columns 96 are fixedly installed on the bottom surface of the electromagnetic plate 93. The magnetic attraction columns 96 have a columnar structure and are made of magnetically conductive material. The magnetic attraction columns 96 extend vertically downward. A metal plate is fixedly installed on the outer side of the limiting frame 51. 94. The metal plate 94 has a flat structure and is made of ferromagnetic material. It is positioned directly below and parallel to the electromagnetic plate 93. A slot 95, a circular through-slot, extends vertically on the metal plate 94. A slidable plate 91 is slidably disposed within the slot 95, sliding up and down along its extension. Two adsorption holes 97 are also provided on the metal plate 94, positioned relative to two... The magnetic column 96 is positioned correspondingly, and the diameter of the adsorption hole 97 is adapted to the outer diameter of the magnetic column 96. The adsorption hole 97 penetrates the upper and lower walls of the metal plate 94 in a vertical direction. A support spring 98 is provided between the electromagnetic plate 93 and the metal plate 94. The support spring 98 is sleeved on the outside of the push-pull column 92. The upper end of the support spring 98 abuts against the lower surface of the electromagnetic plate 93, and the lower end of the support spring 98 abuts against the upper surface of the metal plate 94. The support spring 98 is in a compressed state and always applies an upward elastic force to the electromagnetic plate 93.

[0028] When the first guide plate 7 and the second guide plate 8 are in the raised state, the elastic force of the support spring 98 pushes the electromagnetic plate 93 upward. The electromagnetic plate 93, through the push-pull column 92 and the clamping plate 91, drives the first guide plate 7 upward, and the first guide plate 7 simultaneously drives the second guide plate 8 upward. At this time, the lower ends of the first guide plate 7 and the second guide plate 8 are both higher than the outer surface of the drill bit blank. After the spline groove is processed, when the spiral chip removal groove and the drill bit tooth socket need to be processed, the excitation coil of the electromagnetic plate 93 is energized, and the electromagnetic plate 93 generates a magnetic attraction force. The electromagnetic plate 93 generates a downward magnetic attraction force on the metal plate 94 through the magnetic attraction column 96. Vertically downwards, the magnitude of the magnetic attraction force is greater than the elastic force of the supporting spring 98. The magnetic attraction force is transmitted to the metal plate 94 through the magnetic column 96. At the same time, the electromagnetic plate 93 is subjected to the reaction magnetic attraction force of the metal plate 94. This reaction magnetic attraction force is vertically downwards and acts on the electromagnetic plate 93. Under the action of this reaction magnetic attraction force, the electromagnetic plate 93 overcomes the elastic force of the supporting spring 98 and moves downwards. The electromagnetic plate 93 drives the push-pull column 92 to move downwards. The push-pull column 92 drives the locking plate 91 to slide downwards along the locking groove 95. The locking plate 91 drives the first guide plate 7 to move downwards. The first guide plate 7 drives the second guide plate 8 to move downwards. When the first guide plate 7... When the arc-shaped groove 72 at its bottom aligns with the outer surface of the drill bit neck, the first guide plate 7 stops moving downwards. At this point, the lower end of the first guide plate 7 aligns with the end of the guide body 6, and the extension direction of the first guide groove 71 aligns with the extension direction of the guide body 6 to form a continuous guide path. Simultaneously, the first guide plate 7 and the guide body 6 enclose a chip removal channel, which extends from the end of the spline groove to the lower end of the first guide plate 7. During subsequent machining of the spiral chip removal groove, chips are smoothly discharged through this chip removal channel. The length of the push-pull column 92 is greater than the downward movement of the first guide plate 7 from the raised position to the final pressed position. The distance ensures that when the first guide plate 7 moves down to its final position, the upper end of the push-pull column 92 remains connected to the electromagnetic plate 93, ensuring that the push-pull column 92 will not detach from the electromagnetic plate 93 during the entire downward movement. After the spiral chip removal groove and drill tooth recess are processed, the excitation coil of the electromagnetic plate 93 is de-energized, the magnetic attraction of the electromagnetic plate 93 disappears, and the elastic force of the support spring 98 pushes the electromagnetic plate 93 upward. The electromagnetic plate 93 drives the first guide plate 7 to lift upward through the push-pull column 92 and the clamping plate 91. The first guide plate 7 drives the second guide plate 8 to lift upward, returning to the lifted state, making room for the next spline groove processing.

[0029] A track plate 73 is fixedly installed at the end of the limiting frame 51. The track plate 73 is a plate-shaped structure that extends vertically. A guide rail is provided on the track plate 73, which also extends vertically and is a linear guide rail structure. A slider 74 is fixedly installed on the outer side of the first guide plate 7. The slider 74 slides on the guide rail and slides up and down along the extension direction of the guide rail. During the downward or upward movement of the first guide plate 7, the slider 74 slides along the guide rail. The guide rail constrains the movement direction of the first guide plate 7, ensuring that the first guide plate 7 moves strictly vertically up and down, preventing the first guide plate 7 from tilting or wobbling during movement, and ensuring that the first guide groove 71 of the first guide plate 7 can accurately align with the extension direction of the guide body 6 after each downward press.

[0030] A cooling pipe 18 is installed on the tool holder plate 13. The cooling pipe 18 is a tubular structure, and coolant flows inside the cooling pipe 18. Multiple cooling nozzles 19 are installed on the cooling pipe 18, and the cooling nozzles 19 are connected to the interior of the cooling pipe 18. The outlet end of the cooling nozzle 19 faces the internal machining area of ​​the limiting frame 51. Multiple through holes are opened on the side wall of the limiting frame 51, and the number of through holes corresponds to the number of cooling nozzles 19. The position of the through holes corresponds to the position of the cooling nozzles 19. The cooling nozzles 19 extend into the through holes and spray coolant into the internal machining area of ​​the limiting frame 51. Coolant is sprayed onto the cutting contact area between the milling cutter body 14 and the drill blank. The coolant carries away a large amount of cutting heat generated during the cutting process, reduces the temperature of the cutting area, and reduces thermal wear of the milling cutter body 14. At the same time, the coolant also acts as a lubricant, reducing the frictional resistance between the milling cutter body 14 and the drill blank, and improving the quality of the machined surface. The coolant also carries away the chips generated during the cutting process, flushing them away from the inside of the limiting frame 51 to prevent chips from accumulating in the machining area. Chip discharge ports are provided at the bottom and sides of the limiting frame 51, and the coolant carries the chips out of the chip discharge ports to the outside of the milling machine 1.

[0031] When the aforementioned horizontal CNC milling machine is working, firstly, according to the model and size of the down-the-hole drill bit to be processed, select the appropriate clamping sleeve 22 of the tail clamping component 2 and the snap-fit ​​plate 34 of the head clamping component 3. The tail of the drill bit blank is loaded into the clamping sleeve 22, and the positioning insert 23 is inserted into the center hole of the tail of the drill bit blank. The head end face of the drill bit blank is then placed against the crown arc-shaped rotating end face 35 of the snap-fit ​​plate 34, and the protrusion of the drill head end face passes through the slot 36. The positioning insert 37 is inserted into the air outlet hole of the drill head end face. The moving motor 41 is started to drive the first threaded rod 42 to rotate, and the threaded sleeve 43 drives the moving seat 16 to move along the guide rail 17, so that the snap-fit ​​plate 34 of the head clamping component 3 is pressed tightly against the drill head end face. At this time, the drill bit blank is clamped. The drill bit blank is held between the tail clamping component 2 and the head clamping component 3. The clamping sleeve 22 is clamped by the second clamping plate 21, and the intermediate shaft 33 is clamped by the first clamping plate 32, thus completing the clamping of the drill bit blank. The X-axis drive motor, Y-axis drive motor and Z-axis drive motor in the three-dimensional adjustment component are started to adjust the milling cutter body 14 to the starting position for machining the spline groove. The spindle motor is started to drive the milling cutter body 14 to rotate. The rotation motor 24 and the indexing drive motor 31 are started to rotate the drill bit blank to the machining angle of the first spline groove. The milling cutter body 14 is fed along the guide groove on the limiting frame 51 to machine the first spline groove on the surface of the drill bit blank. During the machining process, the cooling pipe 18 sprays coolant into the machining area through the cooling nozzle 19. The chips are discharged from the chip outlet with the coolant. After the first spline groove is machined, the milling cutter body 14 retracts along the guide groove. The excitation coil of the electromagnetic plate 93 is energized, and the electromagnetic plate 93 generates a magnetic attraction force. The magnetic attraction force overcomes the elastic force of the support spring 98, causing the push-pull column 92 to drive the clamping plate 91 to slide downward along the clamping groove 95. The first guide plate 7 and the second guide plate 8 move downward synchronously. The first guide plate 7 moves down until its arc groove 72 fits against the outer circular surface of the drill neck. The first guide groove 71 aligns with the extension direction of the guide body 6. Then, the three-dimensional adjustment component is activated to adjust the milling cutter body 14 to the entrance of the first guide groove 71. The milling cutter body 14 feeds along the first guide groove 71. Using the machined first spline groove as a reference, a spiral chip removal groove corresponding to the spline groove is machined on the drill head, while the chips are cut. Chips are smoothly discharged through the chip removal channel formed by the first guide plate 7 and the guide body 6. After the spiral chip removal groove is processed, the milling cutter body 14 is withdrawn. The milling cutter body 14 is replaced with a toothed groove milling cutter or the position of the milling cutter body 14 is adjusted to the entrance of the second guide groove 81. The milling cutter body 14 is fed along the second guide groove 81. Based on the processed first spline groove, a drill toothed groove corresponding to the spline groove is processed on the end face of the drill head. For spiral chip removal groove and drill toothed groove processing, the milling cutter needs to be replaced. After the drill toothed groove is processed, the milling cutter body 14 is withdrawn, the excitation coil of the electromagnetic plate 93 is de-energized, the magnetic attraction disappears, and the elastic force of the support spring 98 pushes the electromagnetic plate 93 upward. The first guide plate 7 and the second guide plate 8 are simultaneously lifted and reset.Then, the rotating motor 24 and the indexing drive motor 31 drive the drill bit blank to rotate by a predetermined angle to the machining angle of the second spline groove. The above steps are repeated to machine the second spline groove, the corresponding spiral chip removal groove, and the drill tooth recess in sequence, until all splines, spiral chip removal grooves, and drill tooth recesses are machined. Since each spiral chip removal groove and each drill tooth recess uses the corresponding machined spline groove as the machining reference, the positional accuracy of all spiral chip removal grooves and drill tooth recesses relative to the spline groove is reliably guaranteed. Furthermore, since the drill bit blank only needs to be clamped once during the entire machining process, the cumulative positioning error caused by multiple clampings is avoided, significantly improving the machining accuracy and efficiency of down-the-hole drill bits.

[0032] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0033] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A high-rigidity horizontal CNC milling machine for machining spiral grooves in drill bits, comprising a milling machine outer unit (1), a base (11) provided inside the milling machine outer unit (1), a slide plate (12) provided above the base (11), and a tool holder plate (13) provided on the slide plate (12), a milling cutter body (14) mounted on the tool holder plate (13), wherein the milling machine outer unit (1) is provided with a three-dimensional adjustment component for adjusting the position of the milling cutter body (14) in three-dimensional coordinates, characterized in that: The base (11) is provided with a fixed seat (15) and a movable seat (16). The fixed seat (15) is equipped with a tail clamping component (2) for clamping the tail of the drill bit blank, and the movable seat (16) is equipped with a head clamping component (3) for clamping the head of the drill bit blank. A movable component (4) is installed on the outside of the base (11) to drive the movable seat (16) so that the drill bit blank is clamped between the tail clamping component (2) and the head clamping component (3). A limiting component (5) is installed on the outside of the tail clamping component (2). The limiting component (5) includes a limiting frame (51) located above the outer spline of the drill bit blank. A guide groove adapted to the cross section of the spline groove is provided on the limiting frame (51). The milling cutter body (14) feeds along the guide groove to process the spline groove on the surface of the drill bit blank. A guide body (6) is provided at the lower part of the limiting frame (51). The guide body (6) is located at the outlet end of the spline groove. The starting end of the guide body (6) is connected to the end of the spline groove. The end of the guide body (6) fits against the neck of the drill bit and extends along the preset direction of the spiral chip removal groove. A first guide plate (7) is installed at the end of the limiting frame (51). A guide plate (7) is provided on the first guide plate (7) for guiding the milling cutter to process the spiral chip removal. The first guide groove (71) of the slot, the second guide plate (8) is installed on the outside of the first guide plate (7), the second guide plate (8) is provided with a second guide groove (81) for guiding the milling cutter to process the drill tooth cavity, the first guide plate (7) is installed with a pressing member (9) on the outside of the first guide plate (7), after one spline groove is processed, the pressing member (9) presses the first guide plate (7) down to the end of the guide body (6), so that the first guide groove (71) is connected with the extension direction of the guide body (6), the milling cutter is guided to process the spiral chip removal groove along the first guide groove (71) with the processed spline groove as the reference, and to process the drill tooth cavity along the second guide groove (81), while the first guide plate (7) and the guide body (6) enclose and form a chip removal channel.

2. A high-rigidity horizontal CNC milling machine for machining helical grooves in drill bits according to claim 1, characterized in that: The bottom of the first guide plate (7) and the second guide plate (8) are provided with arc grooves (72). The arc of the arc grooves (72) is adapted to the arc of the outer circle of the drill neck. The length of the second guide plate (8) is shorter than the length of the first guide plate (7). The second guide plate (8) is located on the upper outer side of the first guide plate (7).

3. A high-rigidity horizontal CNC milling machine for machining helical grooves in drill bits according to claim 2, characterized in that: The head clamping component (3) includes an indexing drive motor (31) mounted on a movable seat (16). The output end of the indexing drive motor (31) is equipped with a first chuck (32). The middle part of the first chuck (32) clamps an intermediate shaft (33). The end of the intermediate shaft (33) is equipped with a locking plate (34). The inner side of the locking plate (34) is a crown arc-shaped rotating end face (35) that is adapted to the end face of the drill bit head. The crown arc-shaped rotating end face (35) is provided with a slot (36) for the drill bit head protrusion to pass through.

4. A high-rigidity horizontal CNC milling machine for machining helical grooves in drill bits according to claim 3, characterized in that: The crown arc-shaped rotating end face (35) is also provided with a positioning post (37). The position of the positioning post (37) corresponds to the position of the air outlet hole on the end face of the drill bit. The positioning post (37) is inserted into the air outlet hole on the end face of the drill bit to achieve angular positioning. The intermediate shaft (33) is also equipped with an indexing plate (38). Angle scale lines are engraved on the indexing plate (38). The indexing drive motor (31) drives the intermediate shaft (33) to rotate a predetermined angle according to the scale of the indexing plate (38).

5. A high-rigidity horizontal CNC milling machine for machining helical grooves in drill bits according to claim 2, characterized in that: The moving part (4) includes a moving motor (41) installed on the outside of the base (11). The output shaft of the moving motor (41) is connected to a first threaded rod (42). A threaded sleeve (43) is fixed on the moving seat (16). The threaded sleeve (43) is threadedly engaged with the first threaded rod (42). A guide rail (17) is also provided on the base (11). The moving seat (16) is slidably mounted on the guide rail (17). When the moving motor (41) drives the first threaded rod (42) to rotate, the threaded sleeve (43) drives the moving seat (16) to move linearly along the guide rail (17).

6. A high-rigidity horizontal CNC milling machine for machining helical grooves in drill bits according to claim 1, characterized in that: The tail clamping component (2) includes a second clamping plate (21) mounted on a fixed base (15). The second clamping plate (21) is used to clamp the clamping sleeve (22) at the tail of the drill bit blank. The clamping sleeve (22) is provided with a positioning insertion post (23) inserted into the center hole of the tail of the drill bit. A rotating motor (24) is mounted outside the base (11). The output shaft of the rotating motor (24) is connected to the rotating shaft of the second clamping plate (21) by belt drive. The rotating motor (24) drives the second clamping plate (21) to rotate the clamping sleeve (22) and the drill bit blank.

7. A high-rigidity horizontal CNC milling machine for machining helical grooves in drill bits according to claim 6, characterized in that: The limiting component (5) also includes a fixing ring (52) fixed outside the clamping sleeve (22). A support plate (53) is installed on the fixing ring (52). A hinge plate (54) is fixed at one end of the limiting frame (51). The support plate (53) and the hinge plate (54) are hinged together by a hinge shaft. A locking nut is provided at the hinge to adjust and lock the hinge angle. A tension spring (55) is connected between the support plate (53) and the hinge plate (54). The tension spring (55) provides tension to make the limiting frame (51) deflect toward the drill bit blank. After the guide body (6) fits against the drill bit neck, the tension of the tension spring (55) keeps the guide body (6) in a fitted state with the drill bit neck.

8. A high-rigidity horizontal CNC milling machine for machining spiral grooves in drill bits according to claim 7, characterized in that: The pressing component (9) includes a clamping plate (91) fixed to the side of the first guide plate (7), a push-pull column (92) fixed on the clamping plate (91), an electromagnetic plate (93) fixed to the top of the push-pull column (92), a metal plate (94) fixed to the outside of the limiting frame (51), a slot (95) opened on the metal plate (94), the clamping plate (91) is slidably disposed in the slot (95), two magnetic suction columns (96) are provided on the bottom surface of the electromagnetic plate (93), and the metal plate (94) is provided with... The magnetic column (96) has an adsorption hole (97) corresponding to its position. A support spring (98) is provided between the electromagnetic plate (93) and the metal plate (94). After the spline groove is processed, the electromagnetic plate (93) is energized to generate a magnetic attraction force. The magnetic column (96) is drawn into the adsorption hole (97). The magnetic attraction force overcomes the elastic force of the support spring (98), causing the push-pull column (92) to drive the card plate (91) to slide down along the card groove (95). The first guide plate (7) then moves down to the position where it docks with the end of the guide body (6).

9. A high-rigidity horizontal CNC milling machine for machining helical grooves in drill bits according to claim 8, characterized in that: The width of the limiting frame (51) is greater than the width of the spline groove. The end of the limiting frame (51) is fixed with a track plate (73). The track plate (73) is provided with a vertically extending guide rail. The outer side of the first guide plate (7) is fixed with a slider (74). The slider (74) slides on the guide rail.

10. A high-rigidity horizontal CNC milling machine for machining helical grooves in drill bits according to claim 1, characterized in that: The tool holder plate (13) is equipped with a cooling pipe (18), and the cooling pipe (18) is provided with multiple cooling spray (19) heads. The side wall of the limiting frame (51) is provided with multiple through holes corresponding to the positions of the cooling spray (19) heads. The cooling spray (19) heads extend into the through holes and spray coolant into the processing area inside the limiting frame (51).

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