An internally cooled longitudinal torsional ultrasonic milling tool

Abstract

The present invention relates to an internally cooled longitudinal torsional ultrasonic milling tool, which belongs to the field of milling technology and solves the technical problem that the existing cooling medium cannot be flexibly adjusted according to the cooling requirements of different processing stages and components; the tool includes a tool holder assembly, a joint assembly, a transducer assembly, a tool assembly and a cooling flow channel, the joint assembly includes an outer sleeve and an inner sleeve, the inner sleeve can be moved and inserted into the outer sleeve to form a first position and a second position to achieve adjustment of the cooling medium path, when it is in the first position, the cooling medium flows out of the tool assembly and cools the tool assembly and the cutting area; when it is in the second position, the cooling medium cools the tool holder assembly and the transducer assembly, thereby, the position change of the inner sleeve makes the cooling system have good flexibility and adaptability, and can quickly adjust the flow path and intensity of the cooling medium according to the cooling requirements of different processing stages and different components.

Description

Technical Field

[0001] The invention relates to the technical field of milling, in particular to an internally cooled longitudinal torsional ultrasonic milling tool. Background Art

[0002] Composite materials such as titanium alloys and high-temperature alloys offer excellent properties such as high strength, wear resistance, and corrosion resistance, and are widely used in machinery, aerospace, and marine applications. Milling is typically used to process these composite materials into precision components, but traditional milling processes are inefficient and costly. With the continuous advancement of technology, ultrasonic machining has emerged. Compared to high-speed milling, longitudinal-torsional ultrasonic milling achieves the same machining accuracy at lower speeds, while also reducing cutting forces, reducing tool wear, and extending tool life.

[0003] Long-term processing of the tool will cause the overall temperature of the tool to be too high. In the related art, a flow path of cooling medium is set in the tool to cool the tool part. The flow path of the cooling medium is usually fixed and cannot be flexibly adjusted according to the cooling requirements of different processing stages and components. For example, in some processing stages, the tool assembly requires more cooling, while in other stages, the transducer assembly or the tool holder assembly may also need cooling. Summary of the Invention

[0004] In view of the above analysis, the present invention aims to provide an internally cooled longitudinal torsional ultrasonic milling tool to solve the technical problem in the prior art that the cooling medium cannot be flexibly adjusted according to the cooling requirements of different processing stages and components.

[0005] The purpose of the present invention is mainly achieved through the following technical solutions:

[0006] An internally cooled longitudinal-torsional ultrasonic milling tool comprises a toolholder assembly, a joint assembly, a transducer assembly, a tool assembly, and a cooling channel. The toolholder assembly is connected to a machine tool spindle, the joint assembly is connected between the toolholder assembly and the transducer assembly, the tool assembly is connected to the transducer assembly, and the cooling channel passes through the toolholder assembly, the joint assembly, the transducer assembly, and the tool assembly.

[0007] The joint assembly includes an outer sleeve and an inner sleeve, wherein the outer sleeve is arranged between the tool handle assembly and the transducer assembly, and the inner sleeve is movable through the outer sleeve to form a first position and a second position;

[0008] The outer sleeve is provided with a first inlet and a first outlet. When the inner sleeve is located at the first position, the first inlet is communicated with the inner sleeve to cool the tool assembly. When the inner sleeve is located at the second position, the first inlet is communicated with both the inner sleeve and the first outlet to cool the transducer assembly and the tool assembly.

[0009] The tool assembly is provided with a milling cutter.

[0010] Furthermore, the joint assembly further includes an elastic member, which is disposed between the inner sleeve and the transducer assembly so that the top end of the inner sleeve can block a portion of the first inlet.

[0011] Furthermore, the first inlet includes a central inlet and a circumferential inlet opened at the top end of the outer sleeve. When the inner sleeve is located at the first position, the top end of the inner sleeve is blocked on the central inlet. When the inner sleeve is located at the second position, the top end of the inner sleeve is away from the central inlet.

[0012] Furthermore, the inner sleeve includes a second inlet and a second outlet that are connected to each other, the second inlet is connected to the first inlet, and the second outlet is connected to the cooling channel.

[0013] Furthermore, the tool handle assembly includes a pull pin, a tool handle body and a secondary power supply coil, the pull pin is connected to the machine tool spindle, the tool handle body is connected to the pull pin, and the secondary power supply coil is arranged on the tool handle body to power the transducer assembly.

[0014] Furthermore, the transducer assembly includes a rear cover plate, an amplitude variable rod and a piezoelectric ceramic body, the rear cover plate is connected to the joint assembly, the amplitude variable rod is connected to the rear cover plate, and the piezoelectric ceramic is sleeved on the rear cover plate and abuts against the amplitude variable rod.

[0015] Furthermore, the piezoelectric ceramic body includes a plurality of stacked piezoelectric ceramic units, and the piezoelectric ceramic units include a piezoelectric ceramic sheet and an electrode sheet arranged on the piezoelectric ceramic sheet.

[0016] Furthermore, the amplitude transformer is provided with an amplitude transformer flange, and the amplitude transformer flange is connected to the tool handle assembly.

[0017] Furthermore, the tool assembly includes a chuck and a fastening nut, the milling cutter is inserted into the chuck, the chuck is assembled in the fastening nut, and the fastening nut is connected to the transducer assembly.

[0018] Furthermore, the milling cutter includes a milling cutter body, a main channel and a branch channel. The main channel runs through the milling cutter body and is connected to the cooling channel. One end of the branch channel is connected to the main channel, and the other end of the branch channel is opened between the side wall of the milling cutter and the cutter head.

[0019] Furthermore, the first inlet is connected between the cooling channel and the inner sleeve.

[0020] Furthermore, the first outflow port is communicated with the gap between the tool handle assembly and the transducer assembly.

[0021] Furthermore, the cooling channel includes a first cooling channel, a second cooling channel, a third cooling channel and a fourth cooling channel connected in sequence, the first cooling channel passes through the tool handle assembly, the second cooling channel passes through the joint assembly, the third cooling channel passes through the transducer assembly, and the fourth cooling channel passes through the tool assembly.

[0022] The technical solution of the present invention can achieve at least one of the following effects:

[0023] (1) The inner sleeve of the internally cooled longitudinal torsional ultrasonic milling tool of the present invention is capable of moving inside the outer sleeve, thereby generating a first position and a second position, thereby controlling the flow path and direction of the cooling medium in the cooling channel. When the inner sleeve is at the first position, the cooling medium enters the inner sleeve through the first inlet and passes through the cooling channel, and flows out of the tool assembly to cool the tool assembly and the cutting area; when the inner sleeve is at the second position, a portion of the cooling medium enters the inner sleeve through the first inlet, and a portion of the cooling medium enters the gap between the tool holder assembly and the transducer assembly through the first inlet and the first outlet to cool the two. Therefore, the position change of the inner sleeve makes the cooling system have good flexibility and adaptability, and can quickly adjust the flow path and intensity of the cooling medium according to the cooling requirements of different processing stages and different components;

[0024] (2) In the internally cooled longitudinal torsional ultrasonic milling tool of the present invention, the gap between the tool holder assembly and the transducer assembly is close to or directly facing the secondary power supply coil. The cooling medium flows through the gap between the tool holder assembly and the transducer assembly and directly contacts the secondary power supply coil or is close to the secondary power supply coil, thereby providing cooling for the secondary power supply coil. As a result, the temperature of the secondary power supply coil can be reduced, ensuring that it operates within a safe temperature range, which helps to improve the efficiency and reliability of the secondary power supply coil and extend its service life.

[0025] (3) The internally cooled longitudinal torsional ultrasonic milling tool of the present invention comprises a milling cutter body, a main channel and a branch channel. The outlet of the main channel inside the milling cutter body is divided into a plurality of branch channels, and the main channel is connected to the plurality of branch channels. The cooling medium can flow to the side blade and the processing area, absorb the heat generated during the processing, and reduce the temperature of the bottom blade, side blade and processing area of ​​the tool. At the same time, the cooling medium can reduce the friction coefficient between the blade and the contact surface of the processing area, and reduce the adhesion of chips to the cutting edge. Compared with the straight flow channel with the outlet at the bottom of the tool, the chips are not easy to enter the branch channel, and will not cause the through hole to be blocked, which is convenient for maintenance. Therefore, it can effectively reduce the cutting temperature, reduce tool wear, extend the tool life, optimize the cutting conditions, reduce the temperature of the cutting area, reduce the thermal deformation of the workpiece and the tool caused by high temperature, and improve the processing accuracy.

[0026] In the present invention, the above-mentioned technical solutions can be combined with each other to achieve more preferred combinations. Other features and advantages of the present invention will be described in the following description, and some advantages will become apparent from the description or be learned through practice of the present invention. The objectives and other advantages of the present invention can be realized and obtained through the contents particularly pointed out in the description and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The accompanying drawings are only used for the purpose of illustrating specific embodiments and are not to be considered as limiting the present invention. Throughout the drawings, the same reference symbols denote the same components.

[0028] Figure 1 Schematic diagram of the structure of an internally cooled longitudinal torsional ultrasonic milling tool in an embodiment of the present invention;

[0029] Figure 2 Schematic diagram of the cross-sectional structure of an internally cooled longitudinal torsional ultrasonic milling tool in an embodiment of the present invention;

[0030] Figure 3 for Figure 2 Schematic diagram of the enlarged structure at A in the middle;

[0031] Figure 4 Schematic diagram of the structure of the transducer assembly in an embodiment of the present invention;

[0032] Figure 5 Schematic diagram of the structure of the connector assembly in an embodiment of the present invention;

[0033] Figure 6 Schematic diagram of the flow direction of the cooling medium when the inner sleeve is located in the first position in an embodiment of the present invention;

[0034] Figure 7 Schematic diagram of the flow direction of the cooling medium when the inner sleeve is located at the second position in an embodiment of the present invention;

[0035] Figure 8 A schematic structural diagram of a tool assembly according to an embodiment of the present invention;

[0036] Figure 9 Schematic diagram of the cross-sectional structure of a milling cutter in an embodiment of the present invention;

[0037] Figure 10 This is a modal analysis diagram of a tool without spiral grooves in the prior art;

[0038] Figure 11 is a modal analysis diagram of a tool having a spiral groove (the spiral groove has a rotation direction opposite to that of the milling cutter cutting edge) in an embodiment of the present invention;

[0039] Figure 12 This is a tool modal analysis diagram when the spiral groove and the milling cutter cutting edge have the same rotation direction in an embodiment of the present invention.

[0040] Reference numerals:

[0041] 1-handle assembly, 11-pull nail, 12-handle body, 13-secondary power supply coil;

[0042] 2-transducer assembly, 21-back cover, 22-piezoelectric ceramic body, 221-piezoelectric ceramic sheet, 222-electrode sheet, 23-amplifier, 231-amplifier flange, 232-conical wall;

[0043] 3-connector assembly, 31-outer sleeve, 311-first inlet, 3111-central inlet, 3112-circumferential inlet, 312-first outlet, 32-inner sleeve, 321-second inlet, 322-second outlet, 33-elastic member;

[0044] 4- tool assembly, 41- fastening nut, 42- chuck, 43- milling cutter, 431- milling cutter body, 432- main channel, 433- branch channel;

[0045] 5- cooling channel, 51 first cooling channel, 52 second cooling channel, 53 third cooling channel, 54- fourth cooling channel. DETAILED DESCRIPTION

[0046] The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings, wherein the accompanying drawings constitute a part of the present invention and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not used to limit the scope of the present invention.

[0047] Example 1

[0048] A specific embodiment of the present invention discloses an internally cooled longitudinal torsional ultrasonic milling tool, such as Figure 1 、 Figure 2 and Figure 3As shown, the tool includes a tool handle assembly 1, a joint assembly 3, a transducer assembly 2, a tool assembly 4 and a cooling channel 5. The tool handle assembly 1 is connected to the machine tool spindle, the joint assembly 3 is connected between the tool handle assembly 1 and the transducer assembly 2, the tool assembly 4 is connected to the transducer assembly 2, and the cooling channel 5 runs through the tool handle assembly 1, the joint assembly 3, the transducer assembly 2 and the tool assembly 4; the joint assembly 3 includes an outer sleeve 31 and an inner sleeve 32, and the outer sleeve 31 is arranged between the tool handle assembly 1 and the transducer assembly 2 The inner sleeve 32 can be moved and passed through the outer sleeve 31 to form a first position and a second position; the outer sleeve 31 is provided with a first inlet 311 and a first outlet 312. When the inner sleeve 32 is located at the first position, the first inlet 311 is connected to the inner sleeve 32 to cool the tool assembly 4; when the inner sleeve 32 is located at the second position, the first inlet 311 is connected to both the inner sleeve 32 and the first outlet 312 to cool the transducer assembly 2 and the tool assembly 4; the tool assembly 4 is provided with a milling cutter 43.

[0049] The tool handle assembly 1 is used to connect with the machine tool spindle. The functions of the tool handle assembly 1 include: receiving power, transmitting the power of the machine tool spindle to the joint assembly 3, providing power support for the ultrasonic vibration of the tool assembly 4, and ensuring that the tool assembly 4 can perform effective processing operations; supporting the entire tool and shock-absorbing and buffering, the tool handle assembly 1 can reduce the impact of the vibration of the machine tool spindle on the tool assembly 4, and improve the service life of the tool assembly 4; the joint assembly 3 is used to connect the tool handle assembly 1 and the transducer assembly 2 to ensure close fit and connection between the two; the transducer assembly 2 is used to convert electrical energy into mechanical energy, generate ultrasonic vibration, and transmit the ultrasonic vibration to the tool assembly 4, so that it has the characteristics of longitudinal and torsional composite vibration, thereby improving the cutting performance and processing efficiency of the tool; the tool assembly 4 is used for cutting and processing, and it can receive the ultrasonic vibration generated by the transducer assembly 2 to enhance the cutting ability; The cooling channel 5 runs through the entire tool and can transport the cooling medium to the tool handle assembly 1, the joint assembly 3, the transducer assembly 2 and the tool assembly 4 to cool the entire tool. The cooling medium takes away the heat generated during the cutting process, reduces the temperature of the tool, reduces thermal deformation, and improves the service life and processing accuracy of the tool; the cooling medium passes through the tool assembly 4 and is sprayed to the cutting area, which can play a lubricating role, thereby reducing the friction coefficient between the tool assembly 4 and the workpiece, reducing the cutting force, reducing the wear of the tool, and also helping to reduce the generation of cutting heat, further improving the processing quality and the service life of the tool; illustratively, by adjusting the pressure of the cooling medium in the cooling channel 5, the adjustment of the first position and the second position of the inner sleeve 32 in the outer sleeve 31 is achieved; illustratively, the cooling medium can be a cooling gas, and the cooling gas should be non-corrosive, such as liquid nitrogen, liquid oxygen, liquid argon, This can prevent liquid from entering the handle and contacting the transducer circuit to damage the power supply system.

[0050] Specifically, if Figure 3 、 Figure 5 、 Figure 6 and Figure 7 As shown, the joint assembly 3 includes an outer sleeve 31 and an inner sleeve 32. The outer sleeve 31 is provided with a first inlet 311 and a first outlet 312. The inner sleeve 32 moves in the outer sleeve 31 to generate a first position and a second position, thereby controlling the flow path and direction of the cooling medium in the cooling channel 5. When the inner sleeve 32 is in the first position, the cooling medium enters the inner sleeve 32 through the first inlet 311 and passes through the cooling channel 5 (the dotted arrow in the figure is the flow direction of the cooling medium), and flows out of the tool assembly 4 to cool the tool assembly 4 and the cutting area; when the inner sleeve 32 is in the first position, the cooling medium enters the inner sleeve 32 through the first inlet 311 and passes through the cooling channel 5 (the dotted arrow in the figure is the flow direction of the cooling medium), and flows out of the tool assembly 4 to cool the tool assembly 4 and the cutting area; When the sleeve 32 is in the second position, a portion of the cooling medium enters the inner sleeve 32 through the first inlet 311, and a portion of the cooling medium enters the gap between the tool handle assembly 1 and the transducer assembly 2 through the first inlet 311 and the first outlet 312 to cool the two. Therefore, the position change of the inner sleeve 32 makes the cooling system have good flexibility and adaptability, and can quickly adjust the flow path and intensity of the cooling medium according to the cooling requirements of different processing stages and different components, optimize the cooling effect, and improve the cooling performance and processing efficiency of the entire tool system.

[0051] Among them, the first inlet 311 is connected between the cooling channel 5 and the inner sleeve 32 to cool the tool assembly 4, and the first outlet 312 is connected to the gap between the tool handle assembly 1 and the transducer assembly 2 to cool the transducer assembly 2 and the tool assembly 4.

[0052] like Figure 3 As shown, the upper end of the outer sleeve 31 is connected to the connecting shank assembly 1, and the two can be sealed together. The lower end of the outer sleeve 31 is connected to the transducer assembly 2 (for example, by a thread), and the two can be sealed together. The first flow outlet 312 is opened at the middle end of the outer sleeve 31. Exemplarily, six first flow outlets 312 are opened at the middle end of the outer sleeve 31; a sealing ring can be provided between the inner sleeve 32 and the outer sleeve 31.

[0053] Furthermore, if Figure 3As shown, the connector assembly 3 also includes an elastic member 33, which is arranged between the inner sleeve 32 and the transducer assembly 2 so that the top of the inner sleeve 32 can block part of the first inlet 311; the elastic member 33 provides a reverse force for the inner sleeve 32, so that the top of the inner sleeve 32 can closely contact and block part of the first inlet 311, so that the inner sleeve 32 remains in the first position. Specifically, when the transducer assembly 2 generates ultrasonic vibration, the vibration will be transmitted to the inner sleeve 32, and the elastic member 33 can play a role of buffering and stabilizing The inner sleeve 32 is used to maintain close contact with the first inlet 311 during vibration to achieve sealing, thereby ensuring the stability and controllability of the cooling medium flow path, thereby better controlling the flow direction and flow rate of the cooling medium to achieve cooling and lubrication; when the pressure of the cooling medium in the cooling channel 5 is large enough, the elastic member 33 is compressed to move the inner sleeve 32 downward, and the first inlet 311 is connected to the first outlet 312. At this time, the inner sleeve 32 remains in the second position; illustratively, the elastic member 33 can be a spring.

[0054] Furthermore, if Figure 3 As shown, the first inlet 311 includes a central inlet 3111 and a circumferential inlet 3112 opened at the top of the outer sleeve 31. When the inner sleeve 32 is in the first position, the top of the inner sleeve 32 is blocked on the central inlet 3111; when the inner sleeve 32 is in the first position, its top blocks the central inlet 3111. At this time, the cooling medium flows into the inner sleeve 32 through the circumferential inlet 3112. At this time, the cooling medium can give priority to meeting the cooling needs of the tool assembly 4, ensuring that the cutting area is fully cooled and lubricated. After passing through the tool assembly 4, the cooling medium is directly sprayed into the cutting area, taking away the heat generated during the cutting process, reducing the friction between the tool and the workpiece, thereby improving the processing quality and the service life of the tool; when the inner sleeve 32 is in the second position, the top of the inner sleeve 32 is away from the central inlet 3111. At this time, the central inlet 3111 is no longer blocked. The cooling medium can enter the outer sleeve 31 through the central inlet 3111 and the circumferential inlet 3112 at the same time, and the cooling medium enters the annular space between the outer sleeve 31 and the inner sleeve 32 through the central inlet 3111 and the circumferential inlet 3112. In the annular space, a part of the cooling medium enters the gap between the tool holder assembly 1 and the transducer assembly 2 through the first flow outlet 312 (the first flow outlet 312 is opened because the top of the inner sleeve 32 is away from the central inlet 3111) to cool these components. This design ensures that the tool holder assembly 1 and the transducer assembly 2 can be effectively cooled during operation to prevent performance degradation or damage due to overheating. The other part of the cooling medium still enters through the second flow inlet 321 and flows out from the second flow outlet 322, continuing to flow along the cooling channel 5 to the tool assembly 4, cooling the tool assembly 4 and the cutting area.

[0055] As an improvement to this embodiment, Figure 3 As shown, the inner sleeve 32 includes a second inlet 321 and a second outlet 322 that are connected to each other. The second inlet 321 is connected to the first inlet 311, and the second outlet 322 is connected to the cooling channel 5. The second inlet 321 is the inlet for the cooling medium to enter the inner sleeve 32, and the second outlet 322 is the outlet for the cooling medium to flow out of the inner sleeve 32. When the inner sleeve 32 is in the first position, the top end of the inner sleeve 32 is blocked on the central inlet 3111 of the outer sleeve 31, preventing the cooling medium from entering from the central inlet 3111. The cooling medium passes through the circumferential inlet 3111. 112 enters the second inlet 321 of the inner sleeve 32, and then flows out from the second outlet 322 to enter the cooling channel 5. At this time, the cooling medium mainly flows to the tool assembly 4 to cool and lubricate the tool assembly 4; when the pressure of the cooling medium increases, the cooling medium pushes the inner sleeve 32 from the first position to the second position, and the cooling medium can enter the second inlet 321 and the first outlet 312 of the inner sleeve 32 at the same time through the central inlet 3111 and the circumferential inlet 3112, and then enter the cooling channel 5 and the gap between the tool holder assembly 1 and the transducer assembly 2.

[0056] As an improvement to this embodiment, Figure 1 As shown, the tool handle assembly 1 includes a rivet 11, a tool handle body 12 and a secondary power supply coil 13. The rivet 11 is connected to the machine tool spindle, the tool handle body 12 is connected to the rivet 11, and the secondary power supply coil 13 is arranged on the tool handle body 12 to supply power to the transducer assembly 2; the rivet 11 serves as a connecting piece for connecting the tool handle body 12 to the machine tool spindle, so that the tool handle assembly 1 can be firmly installed on the machine tool; the tool handle body 12 is connected between the rivet 11 and the joint assembly 3 to provide mechanical support for the tool handle assembly 1. Exemplarily, the tool handle body 12 can adopt a BT40 (type of tool handle) tool handle; the secondary power supply coil 13 transmits electrical energy to the transducer assembly 2 through electromagnetic induction or other means, so that the transducer assembly 2 can generate ultrasonic vibration; exemplary, the tool handle body 12 can be in the shape of a truncated cone, the rivet 11 is connected to the top of the tool handle body 12, and the secondary power supply coil 13 is arranged at the bottom of the tool handle body 12.

[0057] On this basis, the gap between the shank assembly 1 and the transducer assembly 2 is close to or facing the secondary power supply coil 13 to provide cooling for the secondary power supply coil 13; thus, the cooling medium flows through the gap between the shank assembly 1 and the transducer assembly 2 and directly contacts the secondary power supply coil 13 or approaches the secondary power supply coil 13, thereby providing cooling for the secondary power supply coil 13. The secondary power supply coil 13 will generate heat in the process of supplying power to the transducer assembly 2. If the heat cannot be dissipated in time, it will affect the performance and life of the secondary power supply coil 13, and then affect the normal operation of the entire tool system. By allowing the cooling medium to flow through the gap, the temperature of the secondary power supply coil 13 can be reduced to ensure that it operates within a safe temperature range, which helps to improve the efficiency and reliability of the secondary power supply coil 13 and extend its service life. At the same time, it also ensures that the transducer assembly 2 can stably receive electricity, maintain the normal generation and transmission of ultrasonic vibrations, and thus ensure the normal operation of the tool.

[0058] As an improvement to this embodiment, Figure 2 and Figure 4 As shown, the transducer assembly 2 includes a rear cover plate 21, an amplitude transformer 23 and a piezoelectric ceramic body 22. The rear cover plate 21 is connected to the joint assembly 3, the amplitude transformer 23 is connected to the rear cover plate 21, and the piezoelectric ceramic body 22 is sleeved on the rear cover plate 21 and abuts against the amplitude transformer 23.

[0059] The rear cover 21 is connected between the joint assembly 3 and the horn 23, and plays a role of mechanical support. In addition, the rear cover 21 also provides a certain sealing performance to prevent external impurities or cooling medium from entering the interior of the transducer assembly 2. The connection between the rear cover 21 and the horn 23 provides an appropriate preload to maintain the overall stiffness of the transducer assembly 2, the stability of the resonant frequency and the working impedance; the main function of the horn 23 is to transmit and amplify the ultrasonic vibration generated by the piezoelectric ceramic body 22, amplify the tiny vibration of the piezoelectric ceramic body 22, and transmit it to the tool assembly 4, thereby enhancing the cutting ability of the tool, and the horn 23 can also adjust the vibration. The impedance of the dynamic system is reduced, so that it is better matched with the tool assembly 4, the energy transfer efficiency is improved, and it is ensured that the ultrasonic vibration can be effectively applied to the cutting process; through the cooperation of the rear cover plate 21, the amplitude transformer 23 and the piezoelectric ceramic body 22, ultrasonic vibration is realized, which reduces the friction and cutting force in the cutting process, reduces the generation of cutting heat, and thus improves the cutting efficiency and the processing surface quality. In addition, combined with the gap between the tool handle assembly 1 and the transducer assembly 2, the cooling medium can effectively cool the piezoelectric ceramic body 22 and the amplitude transformer 23 during the working process, prevent performance degradation or damage due to overheating, and improve the reliability and efficiency of the entire system.

[0060] Specifically, the piezoelectric ceramic body 22 includes a plurality of (even number) stacked piezoelectric ceramic units, and the piezoelectric ceramic unit includes a piezoelectric ceramic sheet 221 and an electrode sheet 222 arranged on the piezoelectric ceramic sheet 221; the piezoelectric ceramic sheet 221 has a piezoelectric effect. When an alternating electric field is applied to the piezoelectric ceramic sheet 221, the piezoelectric ceramic sheet 221 will generate mechanical vibrations, which can significantly reduce cutting force and cutting heat; the electrode sheet 222 is arranged on the piezoelectric ceramic sheet 221 for applying an electric field. Exemplarily, the electrode sheet 222 can be made of a conductive material and can uniformly apply the electric field to the piezoelectric ceramic sheet 221 to ensure that the piezoelectric ceramic sheet 221 can effectively generate vibrations. Through the design of stacked piezoelectric ceramic units, the piezoelectric ceramic body 22 can provide powerful ultrasonic vibration energy for the ultrasonic tool, which can significantly improve the cutting performance of the tool and meet the needs of efficient and precise machining.

[0061] Furthermore, a horn flange 231 is provided on the horn 23 , and the horn flange 231 is connected to the shank assembly 1 .

[0062] The horn flange 231 is used to connect the horn and the handle assembly. The horn 23 is firmly fixed to the handle assembly 1 through mechanical connection (such as threaded connection, welding or riveting, etc.) to reduce energy loss and vibration attenuation during vibration transmission, thereby improving the cutting efficiency and processing quality of the tool. In addition, it also helps to reduce wear and fatigue between components and extend the service life of the horn, handle assembly and the entire ultrasonic tool system.

[0063] Furthermore, the cooling channel 5 includes a first cooling channel 51, a second cooling channel 52, a third cooling channel 53 and a fourth cooling channel 54 connected in sequence, the first cooling channel passes through the tool handle assembly, the second cooling channel passes through the joint assembly, the third cooling channel passes through the transducer assembly, and the fourth cooling channel passes through the tool assembly.

[0064] Example 2

[0065] In the embodiment 2 of the present invention, the tool assembly 4 is further improved on the basis of the embodiment 1, such as Figure 8 As shown, the tool assembly 4 includes a chuck 42 and a fastening nut 41 , the milling cutter 43 is inserted into the chuck 42 , the chuck 42 is assembled into the fastening nut 41 , and the fastening nut 41 is connected to the transducer assembly 2 .

[0066] The chuck 42 is used to fix the milling cutter 43, which firmly clamps the milling cutter 43 therein through an internal clamping structure (such as a spring clamp, a wedge clamp, etc.) to ensure that the milling cutter will not loosen during the cutting process. Exemplarily, the chuck 42 adopts an ER (elastic ring) chuck; the fastening nut 41 is used to assemble the chuck 42 on the transducer assembly 2. Exemplarily, the fastening nut 41 adopts an ER fastening nut; the milling cutter 43 is used to cut the cutting area. In addition, the milling cutter 43 also serves as a channel for the cooling medium, introducing the cooling medium into the cutting area, reducing the cutting temperature, and improving the processing quality.

[0067] As an improvement to this embodiment, Figure 8 and Figure 9 As shown, the milling cutter 43 includes a milling cutter body 431, a main channel 432 and a branch channel 433. The main channel 432 runs through the milling cutter body 431, and the main channel 432 is connected to the cooling channel 5. One end of the branch channel 433 is connected to the main channel 432, and the other end of the branch channel 433 is opened between the side wall and the cutter head of the milling cutter 43. For example, the main channel 432 can be linear or spiral, the cross-sectional area of ​​the main channel 432 can be circular, and the aperture of the main channel can be adjusted as needed. The branch channel 433 can be linear, and the aperture of the branch channel 433 can also be adjusted as needed. Two branch channels 433 can be set, and both branch channels 433 are connected to the main channel 432.

[0068] It should be noted that the structure of the milling cutter 43 is not limited thereto and can be adjusted according to different processing requirements, for example, by changing the number and position of the branch channels 433 and optimizing the distribution of the cooling medium to adapt to different cutting conditions.

[0069] The milling cutter body 431 is the part that directly contacts the workpiece and performs cutting. It has a specific geometric shape and cutting edge and can remove material with the assistance of ultrasonic vibration. The milling cutter body 431 provides physical support for the cooling medium channel (main channel 432 and branch channel 433) to ensure that the cooling medium can flow smoothly; the main channel 432 can pass through the milling cutter body 431 as a whole or partially, as a channel for conveying the cooling medium, which obtains the cooling medium by being connected to the cooling channel 5. The branch channel 433 is connected at the lower end of the main channel 432. Therefore, the main channel 432 also has the function of distributing the cooling medium. By distributing the cooling medium to each branch channel 433, the cooling medium can flow evenly to each cutting area of ​​the milling cutter 43; one end of the branch channel 433 is connected to the main channel 432, and the other end is opened between the side wall and the cutter head of the milling cutter 43, that is, the position of the cutter tip. Therefore, the cooling medium can be directly sprayed into the cutting area to provide cooling and lubrication for the contact part between the cutter head of the milling cutter 43 and the workpiece. In addition, The injection of cooling medium can also reduce cutting force, improve chip discharge, further optimize cutting conditions, and improve processing quality and efficiency. Structurally, the outlet of the main channel 432 inside the milling cutter body 431 is divided into multiple branch channels 433 (for example, two), and the main channel 432 connects multiple branch channels 433. The cooling medium can flow to the side blades and the processing area, absorb the heat generated during the processing, and reduce the temperature of the tool bottom blade, side blade and processing area. At the same time, the cooling medium can reduce the friction coefficient between the blade and the contact surface of the processing area, and reduce the adhesion of chips to the cutting edge. Compared with the straight flow channel with the outlet at the bottom of the tool, the chips are not easy to enter the branch channel 433, and will not cause blockage of the through hole, which is convenient for maintenance. By coordinating the main channel 432 and the branch channel 433, the cutting temperature can be effectively reduced, the tool wear can be reduced, the tool life can be extended, and the cutting conditions can be optimized. Through effective cooling, the temperature of the cutting area is reduced, the thermal deformation of the workpiece and the tool caused by high temperature is reduced, and the processing accuracy is improved.

[0070] Example 3

[0071] In the third embodiment of the present invention, the horn 23 is improved on the basis of the first or second embodiment, such as Figure 1 、 Figure 2 and Figure 4 As shown, the amplitude transformer 23 also includes a conical wall 232, and a plurality of spiral grooves are provided on the conical wall 232 to convert the longitudinal vibration generated by the piezoelectric ceramic body 22 into a longitudinal-torsional composite vibration. Compared with ordinary milling and longitudinal ultrasonic milling, longitudinal-torsional resonance milling has good processing stability, small cutting force, low cutting heat, and can reduce tool wear. Exemplarily, four spiral grooves are provided on the conical wall 232.

[0072] The conical wall 232 is used to transmit the longitudinal vibration generated by the piezoelectric ceramic body 22 to the tool assembly 4. Its conical structure helps to concentrate and amplify the vibration energy and improve the vibration transmission efficiency. The multiple spiral grooves arranged thereon are used to realize longitudinal-torsional composite vibration. When the longitudinal vibration generated by the piezoelectric ceramic body 22 is transmitted through the conical wall 232, the spiral grooves will guide the vibration energy to propagate along the spiral path, thereby converting the longitudinal vibration into longitudinal-torsional composite vibration, thereby significantly improving the cutting efficiency and processing quality of the tool; in addition, the spiral grooves can also optimize the distribution of vibration energy and ensure that the vibration energy is evenly transmitted to various parts of the tool assembly 4, which helps to improve the stability and consistency of the cutting process. Through the conical wall 232 and the multiple spiral grooves arranged thereon, the longitudinal vibration is converted into longitudinal-torsional composite vibration. During the cutting process, the tool can not only vibrate longitudinally, but also generate torsional vibration. This composite vibration mode can more effectively crush materials, reduce the generation of cutting force and cutting heat, and significantly improve cutting efficiency. Moreover, the composite vibration helps to discharge chips, reduce the adhesion of chips on the tool and workpiece surface, and further optimize the processing surface quality.

[0073] As an optional solution of this embodiment, Figure 4 、 Figure 8 and Figure 9 As shown, the rotation direction of the spiral groove along the axial direction is the same as the rotation direction of the cutting edge of the milling cutter 43.

[0074] When the rotation direction of the spiral groove is the same as that of the cutting edge of the milling cutter 43, the longitudinal-torsional composite vibration transmitted by the horn 23 is consistent with the cutting direction of the milling cutter 43. This synergistic effect enables the tool to more effectively crush the material during the cutting process, reducing the generation of cutting force and cutting heat; Figure 10 、 Figure 11 and Figure 12 As shown in the figure, the colored lines represent the direction of vibration transmission. When there is no spiral groove on the amplitude rod 23, the arrows on the amplitude rod 23 and the milling cutter 43 in the velocity vector diagram obtained by simulation are transmitted along the z-axis, which is longitudinal vibration; when there is a spiral groove on the amplitude rod 23, the arrows on the amplitude rod 23 and the milling cutter 43 in the velocity vector diagram of the simulation result spirally diffuse along a certain angle, which is a longitudinal-torsional vibration composed of longitudinal vibration (parallel to the z-axis) and torsional vibration (rotating around the z-axis); when the spiral groove and the cutting edge of the milling cutter 43 have the same rotation direction, the torsional vibration amplitude and the torsional-to-longitudinal ratio (the value of the torsional amplitude divided by the longitudinal amplitude) output by the tool tip are larger; when the rotation direction of the cutting edge is consistent with the rotation direction of the spiral groove, it is helpful to discharge the chips. The chips will be discharged along the rotation direction of the cutting edge during the cutting process, and the design of the spiral groove further optimizes this process, reducing the adhesion of chips to the tool and workpiece surface. The rotation direction of the cutting edge is consistent with the rotation direction of the spiral groove, so that the tool can more evenly bear the cutting force and vibration energy during the cutting process, reducing local wear of the tool and extending the tool life.

[0075] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by any technician familiar with this technical field within the technical scope disclosed by the present invention should be covered by the scope of protection of the present invention.

Claims

1. An internally cooled longitudinal torsional ultrasonic milling tool, characterized in that: The invention comprises a tool handle assembly, a joint assembly, a transducer assembly, a tool assembly and a cooling channel, wherein the tool handle assembly is connected to a machine tool spindle, the joint assembly is connected between the tool handle assembly and the transducer assembly, the tool assembly is connected to the transducer assembly, and the cooling channel passes through the tool handle assembly, the joint assembly, the transducer assembly and the tool assembly; The joint assembly includes an outer sleeve, an inner sleeve, and an elastic member. The outer sleeve is arranged between the tool handle assembly and the transducer assembly. The inner sleeve can be moved through the outer sleeve to form a first position and a second position. The elastic member is arranged between the inner sleeve and the transducer assembly so that the top end of the inner sleeve can block a portion of the first inlet. The outer sleeve is provided with a first inlet and a first outlet; when the inner sleeve is in the first position, the first inlet is communicated with the inner sleeve to cool the tool assembly; when the inner sleeve is in the second position, the first inlet is communicated with both the inner sleeve and the first outlet to cool the transducer assembly and the tool assembly; The inner sleeve comprises a second inlet and a second outlet that are in communication with each other, the second inlet is in communication with the first inlet, and the second outlet is in communication with the cooling channel; The first inlet includes a central inlet and a circumferential inlet opened at the top end of the outer sleeve. When the inner sleeve is in the first position, the top end of the inner sleeve is blocked on the central inlet. When the inner sleeve is in the second position, the top end of the inner sleeve is away from the central inlet. The tool assembly is provided with a milling cutter.

2. The internally cooled longitudinal torsional ultrasonic milling tool according to claim 1, characterized in that: The tool handle assembly includes a pull nail, a tool handle body and a secondary power supply coil. The pull nail is connected to the machine tool spindle, the tool handle body is connected to the pull nail, and the secondary power supply coil is arranged on the tool handle body to supply power to the transducer assembly.

3. The internally cooled longitudinal torsional ultrasonic milling tool according to claim 1, characterized in that: The transducer assembly includes a rear cover plate, an amplitude rod and a piezoelectric ceramic body. The rear cover plate is connected to the joint assembly, the amplitude rod is connected to the rear cover plate, and the piezoelectric ceramic body is sleeved on the rear cover plate and abuts against the amplitude rod.

4. The internally cooled longitudinal torsional ultrasonic milling tool according to claim 3, characterized in that: The piezoelectric ceramic body includes a plurality of stacked piezoelectric ceramic units, each of which includes a piezoelectric ceramic sheet and an electrode sheet disposed on the piezoelectric ceramic sheet.

5. The internally cooled longitudinal torsional ultrasonic milling tool according to claim 3, characterized in that: The amplitude rod is provided with an amplitude rod flange, and the amplitude rod flange is connected to the tool handle assembly.

6. The internally cooled longitudinal torsional ultrasonic milling tool according to claim 1, characterized in that: The tool assembly includes a chuck and a fastening nut. The milling cutter is inserted into the chuck. The chuck is assembled in the fastening nut. The fastening nut is connected to the transducer assembly.

7. The internally cooled longitudinal torsional ultrasonic milling tool according to claim 6, characterized in that: The milling cutter includes a milling cutter body, a main channel and a branch channel. The main channel runs through the milling cutter body and is connected to the cooling channel. One end of the branch channel is connected to the main channel, and the other end of the branch channel is opened between the side wall of the milling cutter and the cutter head.

Images