A continuously adjustable micro inverted taper hole processing mechanism

Abstract

The application relates to the technical field of electric spark machining equipment, and improves the problem that a single electric spark machining equipment can only machine single-angle inverted taper holes; a continuous adjustable micro inverted taper hole machining mechanism is disclosed, which comprises a feeding unit, a taper swinging unit and a liquid impact unit; the taper swinging unit comprises a rotating shaft sleeve, a second driving assembly for driving the rotating shaft sleeve to rotate, a chuck installed in the rotating shaft sleeve and a positioning end cover fixed on the rotating shaft sleeve, a guide is installed in the chuck in the axial direction, and the feeding unit feeds an electrode wire to the guide; the bottom end of the guide is conical, the positioning end cover has a spherical surface with the vertex of the taper angle of the guide as the spherical center, and the chuck is provided with a matching part matched with the spherical surface of the guide; when the chuck is subjected to an adjusting force, the matching part can slide on the positioning end cover, so that the chuck is inclined relative to the central axis of the rotating shaft sleeve; different inverted taper hole machining with different tapers can be realized by adjusting different inclination angles; the electric spark machining equipment does not need to be replaced, and the production cost is reduced.

Description

Technical Field

[0001] This application relates to the technical field of electrical discharge machining equipment, and in particular to a continuously adjustable micro-conical hole machining mechanism. Background Technology

[0002] Electrical discharge machining (EDM) utilizes the instantaneous high temperature generated by the pulsed spark discharge between the electrode wire 200 and the workpiece to melt or even vaporize the workpiece material, thereby achieving the purpose of localized removal of material. EDM has advantages such as non-contact machining and independence from the hardness of the workpiece material, and has made significant progress in practical application in recent years.

[0003] With the rapid development of industries such as automobiles, medical devices, military, and aerospace, the application of micro-holes in precision equipment is becoming increasingly widespread, and micro-precision machining has become an important research and development direction for electrical discharge machining (EDM) technology. Especially in the machining of engine fuel injector nozzles, because inverted conical nozzles have a higher flow coefficient and better spray effect, current fuel injector holes mostly adopt... Figure 1 The micro-conical hole shown can be machined with higher precision on workpiece 100 by micro-electrical discharge machining.

[0004] However, the required taper hole opening angles are different in different precision equipment, and a single piece of equipment may also have taper holes with different angles. Current electrical discharge machining (EDM) equipment can only open taper holes with a specified angle. When different holes need to be opened, it is necessary to change to another EDM equipment, which is not only troublesome to operate and leads to a decrease in production efficiency, but also increases production costs. Summary of the Invention

[0005] In order to overcome the limitation that a single EDM machine can only process a single-angle inverted conical hole, this application provides a continuously adjustable micro inverted conical hole processing mechanism.

[0006] This application provides a continuously adjustable micro-conical hole machining mechanism, which adopts the following technical solution: A continuously adjustable micro-conical hole machining mechanism includes a feeding unit, a conical swing unit, and a flushing unit. The feeding unit includes a vertically arranged guide tube and a first drive assembly for driving the guide tube to move vertically. The conical swing unit includes a rotating sleeve located below the guide tube, a second drive assembly for driving the rotating sleeve to rotate about a vertical axis, a chuck movably mounted inside the rotating sleeve, and a positioning end cap fixed to the rotating sleeve. A guide is axially fixedly mounted inside the chuck, and the electrode wire passes through from above. The guide wire tube and the guide are sequentially inserted downwards; the bottom end of the guide extending out of the chuck is conical, and the positioning end cap has a spherical surface with the vertex of the conical part of the guide as the center. The outer wall of the chuck is provided with a mating part that spherically engages with the guide. When the chuck is subjected to an adjusting force, the mating part can slide on the positioning end cap, causing the chuck to gradually tilt relative to the central axis of the rotating bushing. The flushing unit is used to impact the working fluid onto the workpiece processed by the electrode wire.

[0007] By adopting the above technical solution, the electrode wire passes through the guide tube from top to bottom and then through the conical bottom end of the guide. The frictional resistance between the mating part and the positioning end cover is relatively large, so the chuck will not move on the positioning end cover when there is no adjustment force. When the first drive assembly reciprocates to drive the guide tube to move up and down, the electrode wire can be continuously fed into the conical pendulum unit, and the guide tube has a good guiding effect on the electrode wire. The second drive assembly drives the rotating bushing to rotate. When the central axis of the guide inside the chuck coincides with the central axis of the rotating bushing... When the electrode wire does not wobble, it discharges electricity to create a fine straight hole on the workpiece. Because of the spherical fit between the mating part and the positioning end cap, "movable" means that when an adjusting force is applied to the chuck, it tilts relative to the central axis of the rotating sleeve. After the force is released, the chuck remains in the tilted state. When the rotating sleeve is driven to rotate, the electrode wire undergoes a conical wobble motion to achieve the machining of a tapered hole in the workpiece. The working fluid enables the workpiece to be machined to the conditions required for the electrode wire's discharge machining. By adjusting the tilt angle of the electrode wire relative to the central axis of the rotating sleeve, the conical wobble angle of the electrode wire can be adjusted, thus achieving the machining of tapered holes with different tapers. This eliminates the need to change the EDM equipment, reducing production costs. The adjustment method is also convenient and quick, improving production efficiency.

[0008] Optionally, the chuck includes a sphere and a cylinder connected eccentrically in a vertical direction. The mating part is disposed on the side wall of the cylinder with the cylinder as the center. The guide is coaxially installed in the cylinder. The rotating bushing has a first limiting groove for the sphere to engage and a movable groove for the cylinder to deflect. When the chuck is in a vertical state, the center line of the cylinder coincides with that of the rotating bushing.

[0009] By adopting the above technical solution, since the sphere and cylinder are set eccentrically in the vertical direction, it is equivalent to the sphere and the guide being eccentric. Therefore, the center line of the first limiting groove and the guide is also eccentric. Through the vertical spherical limiting of the mating part and the positioning end cover, and the horizontal spherical limiting of the sphere and the inner wall of the first limiting groove, the chuck needs to rotate to achieve overall eccentric tilt. Compared with the method of directly pushing the chuck, it can improve the tightness of the connection structure between the chuck and the rotating bushing and the positioning end cover, improve the accuracy of the reverse conical hole machining, and improve the adjustment accuracy by rotating, reducing the occurrence of excessive or insufficient eccentric angle of the guide due to improper force during the adjustment process.

[0010] Optionally, the end face of the rotating shaft sleeve at the opening of the first limiting groove is provided with an annular angular scale along the circumference, and the side of the sphere facing the opening of the first limiting groove is provided with an indicator mark.

[0011] By adopting the above technical solution, since the chuck can only be offset and tilted when it rotates along the positioning end cover, there is a definite relationship between the rotation angle and the tilt angle. By using the indicator mark on the ball to correspond to the angular scale value of the rotating bushing, the tilt angle of the guide can be directly viewed, that is, the taper of the electrode wire machining inverted conical hole can be determined, which improves the convenience of operation and can further ensure the accuracy of machining the inverted conical hole.

[0012] Optionally, the rotating bushing is further provided with a receiving groove for accommodating and allowing the mating part to move. The positioning end cap is installed at the bottom end of the rotating bushing at the opening of the receiving groove. The spherical surface of the positioning end cap protrudes upward and enters the receiving groove. A second limiting groove coaxial with the receiving groove is provided in the middle of the positioning end cap. The column passes through the second limiting groove.

[0013] By adopting the above technical solution, a receiving groove with an inner diameter larger than the movable groove is also provided inside the rotating bushing. This allows the mating part to be covered and provides room for movement of the mating part when adjusting the chuck. The spherical surface is designed to bulge upwards, and the bottom surface of the mating part is concave inwards to form a spherical surface to mate with the positioning end cover. The positioning end cover can cover more of the opening of the receiving groove, making the interior of the rotating bushing a relatively sealed environment, reducing the possibility of debris and dust entering during processing, and ensuring the stability of the operating structure of the conical pendulum unit. Moreover, the inner wall of the first limiting groove can limit the movement path of the ball at the upper end of the chuck, and the inner wall of the second limiting groove can limit the tilt range of the column at the lower end of the chuck, thereby limiting the movement range of the chuck. That is, the distance between the first limiting groove and the second limiting groove and the inner diameter of the second limiting groove can be designed as needed to limit the deflection angle range of the guide, further improving the stability of the electrode wire adjustment angle.

[0014] Optionally, the conical pendulum unit further includes an elastic element disposed in the movable groove and connected to the mating part, the elastic element driving the mating part to move toward the positioning end cap.

[0015] By adopting the above technical solution, the frictional resistance between the mating part and the positioning end cover, as well as the frictional resistance between the ball and the inner wall of the first limiting groove, enables the chuck to automatically lock after the position is adjusted. Furthermore, by using the elastic element to press the positioning end cover against the chuck, the frictional resistance between the chuck and the positioning end cover can be increased, further reducing the possibility of the electrode wire moving off the designated position during the processing.

[0016] Optionally, the conical pendulum unit further includes a ceramic guide sleeve installed in the chuck, the bottom end of the ceramic guide sleeve abutting against the guide, and the electrode wire passing through the ceramic guide sleeve and entering the guide.

[0017] By adopting the above technical solution, since the chuck can only move when the adjustment force is relatively large, in order to avoid being pushed and deformed, the chuck needs to be made of a very hard alloy material. The electrode wire needs to pass through the chuck before entering the guide. In order to avoid the metal chuck affecting the discharge machining of the electrode wire, an insulating ceramic guide sleeve is embedded in the chuck. This makes the discharge state of the electrode wire more stable, and the ceramic guide sleeve can extend the guiding distance to the machining end of the electrode wire, further improving the stability and accuracy of the electrode wire machining.

[0018] Optionally, the first driving component includes a vertically arranged slide rail, a slider connected to the slide rail, and a first driving member that drives the slider to slide on the slide rail. The conduit is fixedly installed on the slider. The slider is also equipped with a wire clamping unit, which includes a pressing member located below the wire guide tube and a third driving component that drives the pressing member to press against or disengage from the electrode wire.

[0019] By adopting the above technical solution, when the guide makes a cone-angle swinging motion, the electrode wire will swing with the guide to a certain extent. Through the pressure limiting of the pressing component, the swing angle of the electrode wire in the suspended part above the cone swinging unit can be reduced, thereby reducing the impact on the machining end below the electrode wire. In addition, during the feeding process of the electrode wire, the clamping and unclamping of the wire clamping unit can make the advancement of the electrode wire more stable compared with feeding only through the wire guide tube, thereby ensuring the stability of the workpiece opening process and further improving the machining accuracy of the workpiece.

[0020] Optionally, the feeding unit further includes an insulating plate covering the side of the slider facing away from the slide rail, and the guide tube and the third drive assembly are respectively mounted on the insulating plate.

[0021] By adopting the above technical solution, since the electrode wire is charged during the processing, in order to protect the feeding unit and the wire clamping unit and reduce the possibility of failure, the electrode wire can be insulated and isolated from the first drive assembly and the third drive assembly by an insulating plate.

[0022] Optionally, a base is fixed to the bottom end of the slide rail, the rotating bushing is rotatably connected to the base, and a compensation unit is also installed on the base. The compensation unit includes a jaw located between the rotating bushing and the pressing member and a fourth driving component for driving the jaw to open and close. When the jaw is closed, it can clamp the electrode wire.

[0023] By adopting the above technical solution, since the electrode wire will be worn during processing, especially during the inverted conical oscillation process, the wear will be greater. Therefore, the feed of the electrode wire can be compensated by the compensation unit. When electrode wire compensation is needed, the fourth drive component drives the gripper to clamp the electrode wire, the third drive component drives the pressing member to disengage from the electrode wire, and the first drive component then drives the wire guide tube and the wire clamping unit to move upward. After moving into position, the pressing member presses the electrode wire again, and the gripper opens to release the electrode wire, thereby completing the electrode wire compensation. This further ensures the stability of the electrode wire processing process, improves the drilling accuracy, and is simple, convenient, and quick to operate.

[0024] Optionally, the second drive assembly includes a second drive member fixed to the base and a pulley fixedly sleeved outside the rotating shaft sleeve. The second drive member has a drive shaft that rotates about a vertical axis, and a transmission belt is sleeved between the drive shaft and the pulley.

[0025] By adopting the above technical solution, the second drive component specifically drives the rotating bushing to rotate through the combination of pulleys and transmission belts. Compared with directly driving the rotating bushing, the drive structure is more stable and the transmission ratio can also be adjusted, so as to adjust the rotation speed of the rotating bushing as needed to meet the processing requirements of different workpieces.

[0026] In summary, this application includes at least one of the following beneficial effects: 1. When the chuck is rotated, the chuck is connected to the positioning end cover and the first limiting groove inside the rotating bushing. The chuck can tilt relative to the central axis of the rotating bushing. When the rotating bushing is driven to rotate, the electrode wire will undergo a cone-angle yaw motion to achieve the machining of the reverse cone hole of the workpiece. 2. By adjusting the tilt angle of the electrode wire relative to the central axis of the rotating bushing, the taper angle of the electrode wire can be adjusted, thereby realizing the machining of inverted taper holes with different tapers. There is no need to change the EDM equipment, which reduces production costs. The adjustment method is also convenient and quick, improving production efficiency. 3. The cooperation of the wire clamping unit and the compensation unit can compensate for the feed of the electrode wire, make up for the loss in the electrode wire processing process, and further improve the stability and accuracy of the electrode wire processing process. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the machining process for the inverted conical hole; Figure 2 This is a schematic diagram of the continuously adjustable micro-conical hole processing mechanism in the embodiments of this application; Figure 3 yes Figure 2 A cross-sectional view along the AA direction; Figure 4 This is a cross-sectional view of the wire clamping unit structure in the embodiments of this application; Figure 5 This is a schematic diagram of the structure of the wire clamping unit, the compensation unit, and the conical pendulum unit in the embodiments of this application; Figure 6 This is a cross-sectional view of the conical pendulum unit in the embodiments of this application, excluding the second drive component; Figure 7 This is a schematic diagram of the chuck structure in an embodiment of this application; Figure 8 This is a schematic diagram of the rotating bushing in an embodiment of this application; Figure 9 This is a cross-sectional view of the chuck and rotating bushing in the embodiment of this application, showing the maximum eccentricity angle between them. Figure 10 This is a top view of the collet and rotating bushing in a concentric state in an embodiment of this application; Figure 11 This is a top view of the chuck and rotating bushing in an embodiment of this application, where they have a certain eccentric angle. Figure 12 This is a top view of the chuck and rotating bushing in the embodiment of this application, showing the maximum eccentricity angle.

[0028] Explanation of reference numerals in the attached drawings: 100, workpiece; 200, electrode wire; 1, feed unit; 11, wire guide tube; 111, first wire threading hole; 12, first drive assembly; 121, slide rail; 122, slider; 123, first drive component; 13, insulating plate; 14, clamping plate; 2, conical pendulum unit; 21, rotating bushing; 211, first limiting groove; 212, movable groove; 213, receiving groove; 214, angle scale; 22, second drive assembly; 221, second drive component; 222, pulley; 223, transmission belt; 23, chuck; 2 31. Sphere; 232. Column; 233. Mating part; 234. Indicator mark; 235. Mounting groove; 24. Positioning end cap; 241. Spherical surface; 242. Second limiting groove; 25. Elastic element; 26. Ceramic guide sleeve; 261. Second wire threading hole; 27. Guide; 271. Third wire threading hole; 28. Bearing; 3. Flushing unit; 31. Press pump; 32. Flushing pipe; 4. Wire clamping unit; 41. Pressing element; 42. Third drive assembly; 5. Compensation unit; 51. Claw; 52. Fourth drive assembly; 6. Base. Detailed Implementation

[0029] The following is in conjunction with the appendix Figure 2-12 This application will be described in further detail.

[0030] Reference Figure 2 and Figure 3 This application discloses a continuously adjustable micro-conical hole machining mechanism, including a feed unit 1, a conical swing unit 2, and a flushing unit 3. The conical swing unit 2 includes a rotating bushing 21, a second drive assembly 22 that drives the rotating bushing 21 to rotate, a chuck 23 installed inside the rotating bushing 21, and a positioning end cap 24 fixed on the rotating bushing 21. A guide 27 is installed axially inside the chuck 23. The feed unit 1 feeds the electrode wire 200 toward the guide 27. The bottom end of the guide 27 is conical. The positioning end cap 24 has a spherical surface 241 with the apex of the conical angle of the guide 27 as the center. The chuck 23 is provided with a mating part 233 that spherically engages with the guide 27. When the chuck 23 is subjected to an adjustment force, the mating part 233 can slide on the positioning end cap 24, so that the chuck 23 is tilted relative to the central axis of the rotating bushing 21. By adjusting different tilt angles, different conical holes with different tapers can be machined without changing the EDM equipment, thus reducing production costs.

[0031] Reference Figure 2The feeding unit 1 includes a guide tube 11 arranged vertically and a first driving component 12 that drives the guide tube 11 to move vertically. The electrode wire 200 passes through the guide tube 11 from top to bottom. When the first driving component 12 reciprocates to drive the guide tube 11 to move up and down, the electrode wire 200 can be continuously fed into the conical pendulum unit 2. Moreover, the guide tube 11 has a good guiding effect on the electrode wire 200. Specifically, the first drive assembly 12 includes a vertically arranged slide rail 121, a slider 122 connected to the slide rail 121, and a first drive member 123 that drives the slider 122 to slide on the slide rail 121. The first drive member 123 is fixed to the top of the slide rail 121. A lead screw is provided inside the slide rail 121. The first drive member 123 is a servo motor that drives the lead screw to rotate. The slider 122 is threadedly connected to the lead screw and is linearly guided by the slide rail 121. A wire guide tube 11 is fixedly installed on the slider 122. A first wire-passing hole 111 with an inner diameter 2-4 times the diameter of the electrode wire 200 is opened vertically through the wire guide tube 11. The electrode wire 200 passes through the first wire-passing hole 111. The opening at the upper end of the first wire-passing hole 111 is flared to facilitate the entry of the electrode wire 200. When the first drive member 123 drives the lead screw to rotate, it can realize the movement of the slider 122, that is, drive the wire guide tube 11 to move up and down, thereby realizing the feeding of the electrode wire 200.

[0032] Furthermore, since the electrode wire 200 is charged during the processing, in order to protect the feed unit 1 and the wire clamping unit 4 and reduce the possibility of failure during the electrical discharge machining process, the feed unit 1 also includes an insulating plate 13 covering the side of the slider 122 facing away from the slide rail 121. The insulating plate 13 can be fixed to the slider 122 by bolts. A clamping plate 14 is fixedly connected to the insulating plate 13. The clamping plate 14 has a connection hole that is interference-fitted with the wire guide tube 11. The wire guide tube 11 is clamped and installed between the insulating plate 13 and the clamping plate 14, thereby being fixedly installed on the slider 122.

[0033] Because the electrode wire 200 will swing with the guide 27 to a certain extent when the guide 27 is making a cone-angle swinging motion, in order to improve the machining accuracy of the workpiece 100, the continuously adjustable micro-conical hole machining mechanism also includes a wire clamping unit 4.

[0034] Reference Figure 4 and Figure 5The wire clamping unit 4 includes a pressing member 41 located below the wire guide tube 11 and a third driving assembly 42 that drives the pressing member 41 to press against or disengage from the electrode wire 200. A U-shaped fixing frame is connected to the insulating plate 13 below the position corresponding to the clamping plate 14. The third driving assembly 42 is preferably a miniature threaded cylinder. The output shaft of the miniature threaded cylinder approaches or moves away from the insulating plate 13 in a horizontal direction. The pressing member 41 is fixed to the end of the output shaft of the miniature threaded cylinder and is also made of insulating material. When the pressing member 41 presses the electrode wire 200 against the insulating plate 13, it can clamp the electrode wire 200. Through the pressing and limiting of the pressing member 41, the swing angle of the electrode wire 200 in the suspended part above the cone pendulum unit 2 can be reduced, thereby reducing the impact on the machining end below the electrode wire 200. When the slider 122 moves up and down, the clamped electrode wire 200 can be fed downward or retracted upward better, thereby ensuring the stability of the EDM hole opening process of the workpiece 100 and further improving the machining accuracy of the workpiece 100.

[0035] Reference Figure 5 and Figure 6 The electrode wire 200 continues downward through the guide tube 11 into the lower rotating sleeve 21. Specifically, a base 6 is fixed to the bottom end of the slide rail 121, and the rotating sleeve 21 is rotatably mounted in the base 6. A bearing 28 connects the rotating sleeve 21 and the base 6 to make the rotation of the rotating sleeve 21 smoother. The second drive assembly 22 includes a second drive member 221 fixed on the base 6 and located on the side of the slide rail 121, and a pulley 222 fixedly sleeved on the outside of the rotating sleeve 21. The second drive member 221 is preferably a stepper motor, and the second drive member 221 has a drive shaft that rotates on a vertical axis. A transmission belt 223 is sleeved between the drive shaft and the pulley 222. The rotating sleeve 21 is driven to rotate by the cooperation of the pulley 222 and the transmission belt 223. Compared with directly rotating the rotating sleeve 21, the drive structure is more stable, and the transmission ratio can also be adjusted, so that the rotation speed of the rotating sleeve 21 can be adjusted as needed to meet the processing requirements of different workpieces 100.

[0036] In one embodiment, the mating portion 233 of the chuck 23 is spherically engaged with the positioning end cap 24. By pushing one end of the chuck 23, the chuck 23 is tilted to be eccentric with the rotating sleeve 21. Fasteners are also provided inside the rotating sleeve 21 to further fix the chuck 23 after the angle adjustment, so as to realize the machining of reverse tapered holes of different tapers by the electrode wire 200. In other embodiments, the positioning end cap 24 can be coaxially fixed inside the rotating sleeve 21. In this case, the spherical surface 241 of the positioning end cap 24 is convex downward or concave inward and upward. The chuck 23 passes through the positioning end cap 24, and the mating portion 233 is correspondingly located below the positioning end cap 24 and abuts against the spherical surface 241.

[0037] As a preferred embodiment, refer to Figure 6-8 The rotating bushing 21 has a first limiting groove 211, a movable groove 212, and a receiving groove 213 connected from top to bottom with increasing inner diameters. All three grooves are cylindrical. The first limiting groove 211 and the movable groove 212 are eccentrically positioned along their vertical axes, while the movable groove 212 and the receiving groove 213 are coaxially positioned. The chuck 23 includes a ball 231 and a cylinder 232 connected eccentrically along their vertical axes. A guide 27 is coaxially mounted inside the cylinder 232, with its tapered end extending outside the cylinder 232. The ball 231 engages with the first limiting groove 211. The cylinder 232 extends out of the bottom of the rotating bushing 21 after passing through the movable groove 212 and the receiving groove 213. The mating part 233 is formed by the cylinder... Centered on the side wall of the column 232, the mating part 233 is annular and located in the receiving groove 213; the positioning end cover 24 is installed at the bottom of the rotating bushing 21 at the opening of the receiving groove 213, the edge of the positioning end cover 24 abuts against the ground end face of the rotating bushing 21 and is fixedly connected by bolts, the spherical surface 241 of the positioning end cover 24 protrudes upward and enters the receiving groove 213, the bottom surface of the corresponding mating part 233 is recessed inward to form a spherical surface to fit with the positioning end cover 24, the middle part of the positioning end cover 24 is provided with a second limiting groove 242 coaxial with the receiving groove 213, the column 232 passes through the second limiting groove 242, and the conical end of the guide 27 also extends out of the positioning end cover 24, so that the electrode wire 200 can better process the workpiece 100. Optionally but not limitedly, the bottom side of the column 232 is provided with two opposing flat parts to facilitate tool clamping and rotation of the chuck 23.

[0038] It should be noted that when the chuck 23 is in a vertical position within the rotating sleeve 21, the central axis of the column 232 coincides with that of the rotating sleeve 21, while the sphere 231 is eccentric to the rotating sleeve 21. Correspondingly, the movable groove 212, the receiving groove 213, and the second limiting groove 242 are all coaxially arranged with the rotating sleeve 21, while the first limiting groove 211 is eccentric to the rotating sleeve 21. (Refer to...) Figure 6 and Figure 9By using the vertical spherical limiting of the mating part 233 and the positioning end cover 24, and the horizontal spherical limiting of the ball 231 and the inner wall of the first limiting groove 211, the chuck 23 needs to rotate to achieve overall eccentric tilting, which can further improve the tightness of the connection structure between the chuck 23 and the rotating bushing 21 and the positioning end cover 24, thereby improving the accuracy of the reverse conical hole machining and the accuracy of the adjusted reverse conical hole taper. When the chuck 23 is tilted, the movable groove 212 and the receiving groove 213 provide space for the column 232 and the mating part 233 to move, respectively. Furthermore, since the inner wall of the first limiting groove 211 can restrict the movement path of the upper ball 231 of the chuck 23, and the inner wall of the second limiting groove 242 can restrict the tilt range of the lower column 232 of the chuck 23, when the chuck 23 rotates eccentrically to the point where the column 232 abuts against the inner wall of the second limiting groove 242, the tilt angle between the guide 27 through which the electrode wire 200 passes and the central axis of the rotating sleeve 21 is at its maximum value, thereby limiting the movement range of the chuck 23, the distance between the first limiting groove 211 and the second limiting groove 242 or the inner diameter of the second limiting groove 242 can be designed as needed to limit the swing angle range of the guide 27, further improving the stability of the adjustment angle of the electrode wire 200. In this embodiment, the maximum rotation range of the chuck 23 relative to the rotating sleeve 21 is set to 90°, and the tilt angle of the chuck 23 can be between 0-60°.

[0039] Reference Figure 10-12 To further improve operational convenience, the end face of the rotating bushing 21 at the opening of the first limiting groove 211 is provided with an annular angular scale 214 along the circumference. The angular scale 214 has a range of 90°. The side of the ball 231 facing the opening of the first limiting groove 211 is set as a plane, and an indicator mark 234 is provided on the plane. Because the chuck 23 can only offset and tilt when rotating along the positioning end cover 24, there is a definite relationship between the rotation angle and the tilt angle. By corresponding the indicator mark 234 on the ball 231 to the angular scale 214 value of the rotating bushing 21, the tilt angle of the guide 27 can be directly viewed. That is, the taper of the machining inverted conical hole of the electrode wire 200 can be determined, and the accuracy of machining the inverted conical hole can be further guaranteed. (Refer to...) Figure 6 and Figure 10 When the chuck 23 is in a vertical position within the rotating sleeve 21, the indicator mark 234 points to the value of "0" on the angle scale 214. At this time, the electrode wire 200 will machine a micro-straight hole into the workpiece 100. (Refer to...) Figure 11 When the chuck 23 rotates eccentrically within the rotating sleeve 21 with the conical apex of the guide 27 as its center, the indicator mark 234 on the sphere 231 points to the corresponding angular scale 214; refer to Figure 9 and Figure 12When the chuck 23 rotates to its limit position within the rotating sleeve 21, the indicator mark 234 points to the maximum value of the angle scale 214. At this time, the taper of the machined inverted conical hole is at its maximum. If the taper needs to be reduced, simply rotate the chuck 23 back.

[0040] Through the frictional resistance between the mating part 233 and the positioning end cap 24, and the frictional resistance between the ball 231 and the inner wall of the first limiting groove 211, the chuck 23 can automatically lock after its position is adjusted. To further reduce the possibility of the electrode wire 200 moving off-center during processing, refer to... Figure 6 The conical pendulum unit 2 also includes an elastic element 25 disposed in the movable groove 212 and connected to the mating part 233. The elastic element 25 is preferably a spring and sleeved on the column 232. One end of the elastic element 25 abuts against the inner wall of the movable groove 212 near the first limiting groove 211, and the other end is connected to the mating part 233. The elastic element 25 drives the mating part 233 to move toward the positioning end cover 24, thereby increasing the frictional resistance between the chuck 23 and the positioning end cover 24, making the locking state of the chuck 23 more stable.

[0041] Furthermore, because the chuck 23 can only move when the adjustment force is large, it needs to be made of a very hard alloy material to prevent deformation. The electrode wire 200 needs to pass through the chuck 23 before entering the guide 27. (Refer to...) Figure 6 To avoid the metal chuck 23 affecting the electrical discharge machining of the electrode wire 200, a mounting groove 235 is provided in the middle of the chuck 23. The conical pendulum unit 2 also includes a ceramic guide sleeve 26 coaxially fixed in the mounting groove 235 with the guide 27. The bottom end of the ceramic guide sleeve 26 abuts against the guide 27. A second wire-passing hole 261 is provided on the ceramic guide sleeve 26 along the axial direction. A third wire-passing hole 271 communicating with the second wire-passing hole 261 is provided on the guide 27. The electrode wire 200 passes through the ceramic guide sleeve 26 and enters the guide 27. The ends of the second wire-passing hole 261 and the third wire-passing hole 271 for the electrode wire 200 to enter are both flared. The inner diameter of the third wire-passing hole 271 is smaller than the inner diameter of the second wire-passing hole 261. The insulating ceramic guide sleeve 26 can make the discharge state of the electrode wire 200 more stable, and the ceramic guide sleeve 26 can extend the guiding distance to the processing end of the electrode wire 200, further improving the stability and accuracy of the processing of the electrode wire 200.

[0042] Because the electrode wire 200 will experience wear and tear during processing, especially during the inverted cone oscillation process, the wear and tear will be greater. Therefore, refer to... Figure 2 and Figure 5The continuously adjustable micro-conical hole machining mechanism also includes a compensation unit 5 for compensating the feed of the electrode wire 200. The compensation unit 5 includes a gripper 51 located between the rotating bushing 21 and the pressing member 41, and a fourth drive assembly 52 that drives the gripper 51 to open and close. When the gripper 51 is closed, it can clamp the electrode wire 200. The fourth drive assembly 52 is preferably a finger cylinder. When compensation of the electrode wire 200 is required, the fourth drive assembly 52 drives the gripper 51 to clamp the electrode wire 200, the third drive assembly 42 drives the pressing member 41 to disengage from the electrode wire 200, and the first drive assembly 12 then drives the wire guide tube 11 and the wire clamping unit 4 to move upwards. After moving to the correct position, the pressing member 41 presses the electrode wire 200 again, and the gripper 51 opens to release the electrode wire 200, thereby completing the compensation of the electrode wire 200. This further ensures the stability of the electrode wire 200 machining process, improves the hole-opening accuracy, and is simple, convenient, and quick to operate.

[0043] Furthermore, the flushing unit 3 includes a flushing pump 31 and a flushing pipe 32 connected to the flushing pump 31. The flushing pipe 32 impacts the working fluid laterally at the discharge machining point of the workpiece 100. The working fluid enables the workpiece 100 to be processed to achieve the discharge machining conditions of the electrode wire 200.

[0044] The implementation principle of a continuously adjustable micro-conical hole machining mechanism according to an embodiment of this application is as follows: The electrode wire 200 passes through the guide tube 11, the ceramic guide sleeve 26 and the guide 27 from top to bottom and extends out of the tapered bottom end of the guide 27. When the first drive assembly 12 reciprocates to drive the guide tube 11 to move up and down, the electrode wire 200 can be continuously fed into the conical pendulum unit 2. When machining a straight hole, the chuck 23 is in a vertical position. At this time, the electrode wire 200 coincides with the central axis of the rotating sleeve 21. The second drive assembly 22 drives the rotating sleeve 21 to rotate, but the electrode wire 200 will not wobble. At this time, the electrode wire 200 discharges and machines a fine straight hole on the workpiece 100. When machining a tapered hole, the bottom end of the chuck 23 is held by a tool and the chuck 23 is rotated. The chuck 23 will rotate eccentrically inside the rotating sleeve 21 with the cone apex of the guide 27 as the center of the ball. Because the mating part 233 and the positioning end cover 24 are connected by a spherical fit, the ceramic guide sleeve 26 and the guide 27 inside the chuck 23 are tilted relative to the central axis of the rotating sleeve 21. After the force is stopped, the chuck 23 will also be fixed in the tilted state. At this time, when the rotating sleeve 21 is driven to rotate, the electrode wire 200 will wobble at the cone angle to achieve the machining of the tapered hole on the workpiece 100. By rotating at different angles, it is possible to process inverted conical holes with different taper angles, eliminating the need to change the EDM equipment, reducing production costs, and the adjustment method is convenient and quick, thus improving production efficiency.

[0045] The above are all preferred embodiments of this application and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A continuously adjustable micro-conical hole machining mechanism, characterized in that, The device includes a feeding unit (1), a conical pendulum unit (2), and a flushing unit (3). The feeding unit (1) includes a guide tube (11) arranged vertically and a first drive assembly (12) that drives the guide tube (11) to move vertically. The conical pendulum unit (2) includes a rotating bushing (21) located below the guide tube (11), a second drive assembly (22) that drives the rotating bushing (21) to rotate about the vertical axis, a chuck (23) that can be movably installed in the rotating bushing (21), and a positioning end cap (24) fixed on the rotating bushing (21). A guide (27) is fixedly installed axially inside the chuck (23). The electrode wire (200) passes through the guide tube from top to bottom. (11) and the guide (27); the bottom end of the guide (27) extending out of the chuck (23) is conical, and the positioning end cap (24) has a spherical surface (241) with the cone corner vertex of the conical part of the guide (27) as the center. The outer wall of the chuck (23) is provided with a mating part (233) that is connected to the spherical surface of the positioning end cap (24). When the chuck (23) is subjected to an adjusting force, the mating part (233) can slide on the positioning end cap (24), so that the chuck (23) gradually tilts relative to the central axis of the rotating bushing (21). The flushing unit (3) is used to flush the working fluid onto the workpiece (100) processed by the electrode wire (200). The chuck (23) includes a sphere (231) and a cylinder (232) connected eccentrically in the vertical direction. The mating part (233) is set on the side wall of the cylinder (232) with the cylinder (232) as the center. The guide (27) is coaxially installed inside the cylinder (232). The rotating bushing (21) has a first limiting groove (211) for the sphere (231) to engage and a movable groove (212) for the cylinder (232) to deflect. When the chuck (23) is in the vertical state, the center line of the cylinder (232) coincides with that of the rotating bushing (21).

2. The continuously adjustable micro-conical hole machining mechanism according to claim 1, characterized in that, The rotating bushing (21) has an annular angular scale (214) on the end face of the first limiting groove (211) opening, and the sphere (231) has an indicator mark (234) on the side facing the first limiting groove (211) opening.

3. The continuously adjustable micro-conical hole machining mechanism according to claim 1, characterized in that, The rotating bushing (21) is also provided with a receiving groove (213) for accommodating and allowing the mating part (233) to move. The positioning end cap (24) is installed at the bottom end of the rotating bushing (21) at the opening of the receiving groove (213). The spherical surface (241) of the positioning end cap (24) protrudes upward and enters the receiving groove (213). The middle part of the positioning end cap (24) is provided with a second limiting groove (242) coaxial with the receiving groove (213). The column (232) passes through the second limiting groove (242).

4. A continuously adjustable micro-conical hole machining mechanism according to claim 1 or 3, characterized in that, The cone pendulum unit (2) also includes an elastic element (25) disposed in the movable groove (212) and connected to the mating part (233), the elastic element (25) driving the mating part (233) to move toward the positioning end cap (24).

5. The continuously adjustable micro-conical hole machining mechanism according to claim 1, characterized in that, The conical pendulum unit (2) also includes a ceramic guide sleeve (26) installed in the chuck (23). The bottom end of the ceramic guide sleeve (26) abuts against the guide (27). The electrode wire (200) passes through the ceramic guide sleeve (26) and enters the guide (27).

6. The continuously adjustable micro-conical hole machining mechanism according to claim 1, characterized in that, The first driving assembly (12) includes a vertically arranged slide rail (121), a slider (122) connected to the slide rail (121), and a first driving member (123) that drives the slider (122) to slide on the slide rail (121). The wire guide tube (11) is fixedly installed on the slider (122). A wire clamping unit (4) is also installed on the slider (122). The wire clamping unit (4) includes a pressing member (41) located below the wire guide tube (11) and a third driving assembly (42) that drives the pressing member (41) to move to press against or disengage from the electrode wire (200).

7. The continuously adjustable micro-conical hole machining mechanism according to claim 6, characterized in that, The feeding unit (1) further includes an insulating plate (13) covering the side of the slider (122) facing away from the slide rail (121), and the guide tube (11) and the third drive assembly (42) are respectively mounted on the insulating plate (13).

8. The continuously adjustable micro-conical hole machining mechanism according to claim 6, characterized in that, The bottom end of the slide rail (121) is fixed with a base (6), the rotating bushing (21) is rotatably connected to the base (6), and a compensation unit (5) is also installed on the base (6). The compensation unit (5) includes a jaw (51) located between the rotating bushing (21) and the pressing member (41) and a fourth driving component (52) for driving the jaw (51) to open and close. When the jaw (51) is closed, it can clamp the electrode wire (200).

9. The continuously adjustable micro-conical hole machining mechanism according to claim 8, characterized in that, The second drive assembly (22) includes a second drive member (221) fixed on the base (6) and a pulley (222) fixedly sleeved on the rotating shaft sleeve (21). The second drive member (221) has a drive shaft that rotates on a vertical axis, and a transmission belt (223) is sleeved between the drive shaft and the pulley (222).

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