Ultrasonic auxiliary grinding device for superhard micro cutter

Abstract

The ultrasonic auxiliary grinding device comprises an ultrasonic cutter handle, a first-stage ultrasonic assembly is fixedly installed at the end, away from a machine tool spindle, of the ultrasonic cutter handle and comprises a first-stage amplitude-change pole, and a second-stage ultrasonic assembly is fixedly installed at the end, away from the machine tool spindle, of the first-stage amplitude-change pole; the second-stage ultrasonic assembly comprises a second-stage amplitude-change pole and further comprises a grinding wheel set and a plurality of adjusting gaskets, the grinding wheel set comprises a plurality of grinding wheels, the adjusting gaskets are installed on the two sides of the grinding wheels respectively and used for adjusting the positions of the grinding wheels in the axial direction of the first-stage amplitude-change pole, and the first-stage ultrasonic assembly and the second-stage ultrasonic assembly are connected with an ultrasonic power source for supplying power to the first-stage ultrasonic assembly and the second-stage ultrasonic assembly. The two-stage ultrasonic assemblies are arranged to generate axial and radial two-dimensional vibration on the grinding wheel for grinding the cutting edge of the micro cutter, so that the defects of cutting edge micro-collapse, cutter micro-cracks and the like of the cutting edge can be reduced, the lower surface roughness of the cutting edge is obtained, and the service life of the micro cutter is prolonged.

Description

Technical Field

[0001] This invention belongs to the technical field of grinding devices, and relates to an ultrasonic-assisted grinding device for ultrahard micro-tools. Background Technology

[0002] In the production of superhard micro-tools such as PCD, CBN, and diamond, due to the high cost and difficulty in processing superhard raw materials and the small cutting diameter of the tools, grinding is generally used to process superhard micro-tools. However, in the traditional grinding process, the grinding wheel is easily worn. Usually, grinding wheel dressing is required after grinding 3-5 superhard micro-tools, which greatly affects the processing efficiency. At the same time, the grinding force increases after the grinding wheel wears out, which can lead to the breakage of the micro-tools and cause great economic losses. Summary of the Invention

[0003] To address the aforementioned problems, this invention proposes an ultrasonic-assisted grinding device for ultrahard micro-tools, which effectively solves the problems in the prior art.

[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0005] An ultrasonic-assisted grinding device for ultrahard micro-tools includes:

[0006] An ultrasonic tool holder, wherein the ultrasonic tool holder is mounted on a machine tool spindle;

[0007] A primary ultrasonic component is fixedly installed at the end of the ultrasonic shank away from the machine tool spindle, and the primary ultrasonic component includes a primary amplitude transformer.

[0008] A secondary ultrasonic component is fixedly installed at the end of the primary amplitude transformer away from the machine tool spindle, and the secondary ultrasonic component includes a secondary amplitude transformer.

[0009] A grinding wheel assembly, comprising a plurality of grinding wheels sequentially mounted on the first-stage amplitude transformer and a grinding wheel mounted on the second-stage amplitude transformer;

[0010] Adjusting shims, wherein multiple adjusting shims are provided, and the multiple adjusting shims are respectively installed on both sides of the grinding wheel to adjust the position of the grinding wheel in the axial direction of the first-stage amplitude transformer;

[0011] An ultrasonic power supply is used to power the primary ultrasonic component and the secondary ultrasonic component.

[0012] Optionally, the primary ultrasonic component further includes a front cover plate, a copper gasket, a piezoelectric ceramic, a rear cover plate, and a fixing bolt arranged sequentially at the end of the primary amplitude transformer away from the secondary ultrasonic component. The fixing bolt passes through the front cover plate, the copper gasket, the piezoelectric ceramic, and the rear cover plate and is threaded to the primary amplitude transformer.

[0013] Optionally, the first-stage amplitude transformer has an external thread at the end away from the second-stage ultrasonic component, and the ultrasonic scalpel handle has an internal thread at the end near the first-stage ultrasonic component. The first-stage amplitude transformer is threaded to the ultrasonic scalpel handle.

[0014] Optionally, the secondary ultrasonic component also includes a copper washer, a piezoelectric ceramic, and a rear cover plate arranged sequentially at the end of the secondary amplitude transformer near the primary amplitude transformer. A fastening bolt is provided at the end of the rear cover plate away from the piezoelectric ceramic. The fastening bolt passes through the copper washer, the piezoelectric ceramic, and the rear cover plate and is threaded to the secondary amplitude transformer. A fastening nut for fixing the grinding wheel is threaded to the end of the secondary amplitude transformer away from the primary amplitude transformer.

[0015] Optionally, the first-stage amplitude transformer has a groove at the end away from the machine tool spindle, and the groove has an internal thread. The second-stage amplitude transformer has an external thread at the end near the fastening bolt, and the second-stage amplitude transformer is threadedly connected to the first-stage amplitude transformer.

[0016] Optionally, the ultrasonic scalpel handle and the first-stage amplitude transformer are provided with set screw holes in the radial direction, and set screws are connected to the set screw holes by internal threads. When the set screws are tightened, they are lower than the first-stage amplitude transformer and the second-stage amplitude transformer.

[0017] Optionally, the ultrasonic scalpel handle has a through hole in the radial direction, the fixing bolt and the first-stage amplitude transformer have through holes in the axial direction, and a wireless sensing device is provided on the outside of the ultrasonic scalpel handle. The wireless sensing device is electrically connected to the piezoelectric ceramic through the through hole to supply power to it.

[0018] Optionally, the first-stage amplitude transformer is stepped, with its end fitting against the end of the ultrasonic scalpel handle, and a sealing ring is provided between the end of the first-stage amplitude transformer and the end of the ultrasonic scalpel handle.

[0019] Optionally, the grinding wheel is a 45° disc grinding wheel, a flat grinding wheel, a 20° disc grinding wheel, and a cup grinding wheel arranged sequentially on the first-stage amplitude transformer from the position near the machine tool spindle.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] 1. By applying ultrasonic vibration to the grinding wheel assembly through a two-stage ultrasonic component, two-dimensional axial and radial vibrations are generated on the grinding wheel used for grinding the cutting edge of micro-tools. By setting multiple grinding wheels, ultrasonic-assisted grinding of different processing steps can be achieved. Through intermittent contact grinding with ultrasonic assistance, the grinding force and grinding temperature during the grinding of superhard micro-tools are reduced, the surface quality of the tool after grinding is improved, and defects such as micro-chipping and micro-cracks on the cutting edge of the tool are reduced. At the same time, a lower surface roughness of the cutting edge is obtained, and the service life of micro-tools is improved.

[0022] 2. By adjusting the assembly position of different grinding wheels using shims, the ultrasonic vibration amplitude of the grinding wheels used in different processes can be adjusted, effectively reducing grinding wheel wear, increasing the service life of the grinding wheels, and avoiding multiple dressing of the grinding wheels during processing;

[0023] 3. Ultrasonic-assisted grinding of ultrahard micro-tools can also achieve rapid wheel dressing. At the same time, the device is easy to install, highly versatile, suitable for various scenarios, easy to promote and implement, and has good economic benefits. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the overall structure of an embodiment of the present invention;

[0025] Figure 2 This is a schematic diagram of the structure of the primary ultrasound component in an embodiment of the present invention.

[0026] Reference numerals: 1. Ultrasonic scalpel handle; 2. First-stage ultrasonic assembly; 21. First-stage amplitude transformer; 22. Front cover plate; 23. Copper gasket; 24. Piezoelectric ceramic; 25. Rear cover plate; 26. Fixing bolt; 3. Second-stage ultrasonic assembly; 31. Second-stage amplitude transformer; 32. Fastening bolt; 33. Fastening nut; 34. Set screw hole; 4. Grinding wheel assembly; 41. 45° disc grinding wheel; 42. Flat grinding wheel; 43. 20° disc grinding wheel; 44. Cup grinding wheel; 5. Adjusting shim; 6. Wireless sensing device. Detailed Implementation

[0027] 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.

[0028] Please see Figure 1 and Figure 2This invention discloses an ultrasonic-assisted grinding device for ultrahard micro-tools, comprising an ultrasonic tool holder 1 mounted on a machine tool spindle. A primary ultrasonic component 2 is fixedly mounted at the end of the ultrasonic tool holder 1 away from the machine tool spindle. The primary ultrasonic component 2 includes a primary amplitude transformer 21. A secondary ultrasonic component 3 is fixedly mounted at the end of the primary amplitude transformer 21 away from the machine tool spindle. The secondary ultrasonic component 3 includes a secondary amplitude transformer 31, a grinding wheel assembly 4, and multiple adjusting shims 5. The grinding wheel assembly 4 includes multiple grinding wheels sequentially mounted on the primary amplitude transformer 21 and a grinding wheel mounted on the secondary amplitude transformer 31. Multiple adjusting shims 5 are respectively mounted on both sides of the grinding wheel to adjust the position of the grinding wheel in the axial direction of the primary amplitude transformer 21. The primary ultrasonic component 2 and the secondary ultrasonic component 3 are connected to an ultrasonic power supply for powering them.

[0029] Specifically, a primary ultrasonic component 2 and a secondary ultrasonic component 3 are provided on the ultrasonic scalpel handle 1, and grinding wheels are installed on the primary amplitude transformer 21 and the secondary amplitude transformer 31. At the same time, multiple grinding wheels are installed on the primary amplitude transformer 21, and the positions of the multiple grinding wheels can be adjusted by adjusting the shims 5.

[0030] Ultrasonic excitation is applied to the primary ultrasonic component 2 and the secondary ultrasonic component 3 by an ultrasonic power supply, generating high-frequency ultrasonic vibrations on the primary amplitude transformer 21 and the secondary amplitude transformer 31. Due to the propagation characteristics of ultrasonic vibrations, the amplitude of high-frequency ultrasonic vibrations varies at different positions along the axial direction of the primary amplitude transformer 21. The positions of multiple grinding wheels are adjusted by setting adjustment shims 5 to provide the ultrasonic vibration amplitude required for different processing steps. By generating high-frequency vibrations in the grinding wheels, the cutting force during the grinding of micro-tools can be reduced, and defects such as micro-chipping and micro-cracks in the grinding of ultra-hard micro-tools can be reduced. At the same time, by performing intermittent contact grinding with ultrasonic assistance, the grinding temperature during the grinding of ultra-hard micro-tools can be reduced, which can effectively solve the problem of low efficiency in the processing of ultra-hard micro-tools.

[0031] The adjustable shims 5, which can adjust the positions of multiple grinding wheels, can adapt and adjust the ultrasonic vibration amplitude of grinding wheels used in different processes, effectively reducing grinding wheel wear, increasing the service life of grinding wheels, and avoiding multiple dressing of grinding wheels during processing.

[0032] In some feasible ways, to facilitate the adaptation and installation with the machine tool spindle, the ultrasonic tool holder 1 is selected with a standard BT or HSK type interface.

[0033] The primary ultrasonic component 2 also includes a front cover plate 22, a copper gasket 23, a piezoelectric ceramic 24, a rear cover plate 25 and a fixing bolt 26 arranged sequentially at the end of the primary amplitude rod 21 away from the secondary ultrasonic component 3. The fixing bolt 26 passes through the front cover plate 22, the copper gasket 23, the piezoelectric ceramic 24 and the rear cover plate 25 and is threaded to the primary amplitude rod 21.

[0034] The secondary ultrasonic component 3 also includes a copper washer 23, a piezoelectric ceramic 24, and a rear cover plate 25 arranged sequentially at the end of the secondary amplitude transformer 31 near the primary amplitude transformer 21. A fastening bolt 32 is provided at the end of the rear cover plate 25 away from the piezoelectric ceramic 24. The fastening bolt 32 passes through the copper washer 23, the piezoelectric ceramic 24, and the rear cover plate 25 and is threaded to the secondary amplitude transformer 31. A fastening nut 33 for fixing the grinding wheel is threaded to the end of the secondary amplitude transformer 31 away from the primary amplitude transformer 21.

[0035] The ultrasonic power supply generates high-frequency vibration by supplying power to the piezoelectric ceramic 24. The high-frequency vibration is transmitted to the grinding wheel through the first-stage amplitude transformer 21 and the second-stage amplitude transformer 31. The two-stage ultrasonic components generate two-dimensional axial and radial vibrations on the grinding wheel that grinds the cutting edge of the micro-tool. This can reduce defects such as micro-chipping of the cutting edge and micro-cracks in the tool, while obtaining a lower surface roughness of the cutting edge and improving the service life of the micro-tool.

[0036] For easy installation, the first-stage amplitude transformer 21 has an external thread at the end furthest from the second-stage ultrasonic component 3, and the ultrasonic scalpel 1 has an internal thread at the end closest to the first-stage ultrasonic component 2. The first-stage amplitude transformer 21 is threadedly connected to the ultrasonic scalpel 1. The first-stage amplitude transformer 21 also has a groove with an internal thread at the end furthest from the machine tool spindle, and the second-stage amplitude transformer 31 has an external thread at the end closest to the fastening bolt 32. The second-stage amplitude transformer 31 is threadedly connected to the first-stage amplitude transformer 21. This threaded connection facilitates the fixed installation of the first-stage ultrasonic component 2 and the second-stage ultrasonic component 3, and also facilitates the disassembly and adjustment of the grinding wheel and adjusting shims 5.

[0037] To facilitate further fixation of the primary ultrasonic component 2 and the secondary ultrasonic component 3, the ultrasonic scalpel handle 1 and the primary amplitude transformer 21 are radially provided with set screw holes 34. Set screws are internally threaded into the set screw holes 34, and when tightened, the set screws are lower than the primary amplitude transformer 21 and the secondary amplitude transformer 31. The set screws fix the primary ultrasonic component 2 and the secondary ultrasonic component 3, reducing the possibility of the primary amplitude transformer 21 and the secondary amplitude transformer 31 becoming disengaged under high-speed rotation and high-frequency vibration conditions.

[0038] In some feasible embodiments, the primary amplitude transformer 21 is a rod-shaped structure. A ring with a diameter smaller than that of the primary amplitude transformer 21 is provided at the end of the primary amplitude transformer 21 near the ultrasonic scalpel handle 1. The front cover plate 22 is located inside the ring, and the outer side of the ring is threadedly connected to the ultrasonic scalpel handle 1, so that the end of the primary amplitude transformer 21 fits against the end of the ultrasonic scalpel handle 1. A sealing groove is provided between the end of the primary amplitude transformer 21 and the end of the ultrasonic scalpel handle 1, and a sealing ring is placed in the sealing groove to prevent cutting fluid from entering during machining. The front cover plate 22, copper gasket 23, piezoelectric ceramic 24, and rear cover plate 25 are all ring-shaped structures, and fixing bolts 26 pass through the ring holes and are connected to the primary amplitude transformer 21.

[0039] The secondary amplitude transformer 31 has a circular protrusion in the middle, making it a stepped shaft. The outer side of the circular protrusion has an external thread that connects with the primary amplitude transformer 21. After the fastening nut 33 is tightened, the grinding wheel mounted on the secondary amplitude transformer 31 abuts against the adjusting shim 5 on the primary amplitude transformer 21.

[0040] The structural dimensions of the primary amplitude transformer 21 and the secondary amplitude transformer 31 are set according to the ultrasonic transduction amplitude requirements, which are generally multiples of the wavelength used, and are also set to accommodate the installation of the grinding wheel.

[0041] To facilitate the ultrasonic power supply to the primary ultrasonic component 2 and the secondary ultrasonic component 3, the ultrasonic scalpel handle 1 has a through hole along the radial direction, and the fixing bolt 26 and the primary amplitude transformer 21 have through holes along the axial direction. A wireless sensing device 6 is installed on the outside of the ultrasonic scalpel handle 1, and the wireless sensing device 6 is electrically connected to the piezoelectric ceramic 24 through the through hole to supply power. A disc is fixedly installed on the outside of the ultrasonic scalpel handle 1, and the induction coil of the wireless sensing device 6 is installed on the disc. A power supply coil connected to the ultrasonic power supply is installed on the machine tool to facilitate power supply during high-speed rotation.

[0042] In some feasible ways, an electric slip ring structure can also be provided on the outside of the ultrasonic scalpel handle 1, and the cable at the output end of the electric slip ring enters the piezoelectric ceramic 24 through the through hole.

[0043] To facilitate the use of micro-tools, the grinding wheels of the grinding wheel group 4 are arranged in sequence from the position near the machine tool spindle: a 45° disc grinding wheel 41, a flat grinding wheel 42, a 20° disc grinding wheel 43 on the first-stage amplitude transformer 21, and a cup grinding wheel 44 on the second-stage amplitude transformer 31.

[0044] In micro-tool grinding, 45° disc grinding wheels 41 and flat grinding wheels 42 grind helical grooves or cylindrical cutting edges, while 20° disc grinding wheels 43 and cup grinding wheels 44 grind the tool grooves and cutting edges of the micro-tools. Therefore, the 45° disc grinding wheels 41 and flat grinding wheels 42 are fixed near the piezoelectric ceramic 24 on the primary amplitude transformer 21, achieving a larger high-frequency ultrasonic vibration amplitude, significantly reducing grinding force and heat during grinding, and simultaneously obtaining good surface quality. The 20° disc grinding wheel 43 is fixed in the middle position of the primary amplitude transformer 21 to prevent breakage of the micro-tools due to ultrasonic vibration amplitude during grinding. The grinding wheels generate high-frequency axial and radial two-dimensional ultrasonic vibrations under the combined action of the primary and secondary ultrasonic components. Therefore, when grinding the cutting edge of the micro-tool, defects such as micro-chipping and micro-cracks on the cutting edge are reduced, while a lower surface roughness is obtained, improving the service life of the micro-tools.

[0045] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An ultrasonic-assisted grinding device for a micro-superhard cutter, characterized in that, The utility model relates to a kind of ultrasonic cutting tool, including: Ultrasonic cutter handle (1), the ultrasonic cutter handle (1) is installed to machine tool spindle; Primary ultrasonic assembly (2), the primary ultrasonic assembly (2) is fixedly installed to the ultrasonic cutter handle (1) far from machine tool spindle one end, and the primary ultrasonic assembly (2) includes primary amplitude transformer (21); Secondary ultrasonic assembly (3), the secondary ultrasonic assembly (3) is fixedly installed to the primary amplitude transformer (21) far from machine tool spindle one end, and the secondary ultrasonic assembly (3) includes secondary amplitude transformer (31); Grinding wheel group (4), the grinding wheel group (4) includes multiple grinding wheels installed on the primary amplitude transformer (21) in sequence, with the grinding wheel installed on the secondary amplitude transformer (31); Adjusting washer (5), the adjusting washer (5) is provided with multiple, multiple adjusting washer (5) is respectively installed on the both sides of the grinding wheel, to adjust the position of the grinding wheel in the axial direction of the primary amplitude transformer (21); Ultrasonic power supply, the ultrasonic power supply is used to power the primary ultrasonic assembly (2) and secondary ultrasonic assembly (3).

2. The apparatus according to claim 1, wherein: The primary ultrasonic assembly (2) further includes front cover plate (22), copper washer (23), piezoelectric ceramic (24), rear cover plate (25) and fixed bolt (26) arranged in sequence at the primary amplitude transformer (21) far from the secondary ultrasonic assembly (3) one end, the fixed bolt (26) is screwed to the primary amplitude transformer (21) after penetrating through the front cover plate (22), copper washer (23), piezoelectric ceramic (24) and rear cover plate (25).

3. The apparatus according to claim 2, wherein: The primary amplitude transformer (21) is provided with external thread far from the secondary ultrasonic assembly (3) one end, the ultrasonic cutter handle (1) is close to the primary ultrasonic assembly (2) one end and is provided with mounting groove, the mounting groove is provided with internal thread, and the primary amplitude transformer (21) is screwed to the ultrasonic cutter handle (1).

4. The apparatus according to claim 3, wherein: The secondary ultrasonic assembly (3) also includes copper washer (23), piezoelectric ceramic (24) and rear cover plate (25) arranged in sequence at the secondary amplitude transformer (31) close to the primary amplitude transformer (21) one end, the rear cover plate (25) is provided with fastening bolt (32) far from piezoelectric ceramic (24) one end, the fastening bolt (32) is screwed to the secondary amplitude transformer (31) after penetrating through the copper washer (23), piezoelectric ceramic (24) and rear cover plate (25), and the secondary amplitude transformer (31) is screwed to fastening nut (33) for fixing the grinding wheel far from the primary amplitude transformer (21) one end.

5. The apparatus according to claim 4, wherein: The primary amplitude transformer (21) is provided with recess far from machine tool spindle one end, the recess is provided with internal thread, and the secondary amplitude transformer (31) is provided with external thread close to the fastening bolt (32) one end, and the secondary amplitude transformer (31) is screwed to the primary amplitude transformer (21).

6. The apparatus according to claim 5, wherein: The ultrasonic cutter handle (1) and the primary amplitude transformer (21) are provided with jackscrew hole (34) along the radial direction, the jackscrew hole (34) is screwed to the jackscrew, and the jackscrew is below the primary amplitude transformer (21) and secondary amplitude transformer (31) after being screwed.

7. The apparatus according to claim 2, wherein: The ultrasonic knife handle (1) is provided with a through hole in the radial direction, the fixed bolt (26) and the first amplitude lever (21) are provided with a through hole in the axial direction, the ultrasonic knife handle (1) is provided with a wireless induction device (6) on the outside, the wireless induction device (6) is electrically connected with the piezoelectric ceramic (24) through the through hole to supply power for the wireless induction device (6).

8. The apparatus according to claim 2, wherein: The first amplitude lever (21) is in a stepped shape, the end of the first amplitude lever (21) is attached to the end of the ultrasonic knife handle (1), and a sealing ring is arranged between the end of the first amplitude lever (21) and the end of the ultrasonic knife handle (1).

9. The apparatus according to any one of claims 1 to 8, wherein: The grinding wheel is a 45° disc-shaped grinding wheel (41), a flat grinding wheel (42), a 20° disc-shaped grinding wheel (43) arranged on the first amplitude lever (21) in sequence from the position close to the main shaft of the machine tool, and a cup-shaped grinding wheel (44) arranged on the second amplitude lever (31).

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