A three-degree-of-freedom ultra-precision lathe tool holder adjustment system

Abstract

The present invention discloses a three-degree-of-freedom ultra-precision lathe tool rest adjustment system, comprising: a tool rake angle adjustment mechanism, a tool plane angle adjustment mechanism and a vertical lifting platform, wherein the tool rake angle adjustment mechanism is installed on the tool plane angle adjustment mechanism and can rotate around the Y axis to adjust the rake angle of the tool, the tool plane angle adjustment mechanism is installed on the vertical lifting platform and can rotate around the Z axis to adjust the plane angle of the tool, and the vertical lifting platform can move up and down along the Z axis to adjust the height of the tool. Through the above-mentioned method, the present invention can realize multi-degree-of-freedom adjustment of the tool rake angle, plane angle and tool height, and has the characteristics of high adjustment accuracy, high efficiency and high rigidity.

Description

Technical Field

[0001] The invention relates to the technical field of ultra-precision lathes, in particular to a tool holder adjustment system for a three-degree-of-freedom ultra-precision lathe. Background Art

[0002] Ultra-precision machining has become a key technology for the country in international competition. With the development of ultra-precision machining manufacturing technology, ultra-precision single-point diamond lathes can achieve nano-level machining accuracy for non-ferrous metals. Compared with traditional precision machining, low machining efficiency and high costs have become bottlenecks restricting its mass production. In the ultra-precision turning process, the accuracy of tool setting is one of the main factors affecting the machining accuracy of the workpiece. Taking the 2-axis ultra-precision single-point diamond lathe as an example, it is necessary to ensure that the center of the tool tip arc coincides with the rotation axis of the spindle, and the error must be within sub-micron. This has led to tool setting becoming one of the steps that takes the longest time and seriously restricts its machining efficiency.

[0003] The current tool holder adjustment system based on the traditional sliding wedge and flexible hinge is simple in structure and easy to implement. However, due to its mechanical structure, with each adjustment, static friction will be generated between the relatively sliding surfaces of the wedge under the pressure of the flexible hinge. As time goes by, after a few days, the static friction will be released, causing relative sliding between the surfaces, resulting in micron-level deviation between the tool and the zero point. In addition, most tool holder adjustment systems can only achieve linear motion in the horizontal or vertical direction, and cannot achieve rotational motion to adjust the plane angle and rake angle of the tool.

[0004] Therefore, in order to make up for the shortcomings of the tool holder adjustment system based on the cooperation of the traditional sliding wedge and the flexible mechanism, a new type of ultra-precision lathe tool holder adjustment system is continuously developed. Summary of the invention

[0005] The main technical problem solved by the present invention is to provide a three-degree-of-freedom ultra-precision lathe tool holder adjustment system.

[0006] In order to solve the above technical problems, a technical solution adopted by the present invention is: to provide a three-degree-of-freedom ultra-precision lathe tool holder adjustment system, including: a tool rake angle adjustment mechanism, a tool plane angle adjustment mechanism and a vertical lifting platform, the tool rake angle adjustment mechanism is installed on the tool plane angle adjustment mechanism, and can rotate around the Y axis to adjust the rake angle of the tool, the tool plane angle adjustment mechanism is installed on the vertical lifting platform, and can rotate around the Z axis to adjust the plane angle of the tool, and the vertical lifting platform can move up and down along the Z axis to adjust the height of the tool.

[0007] In a preferred embodiment of the present invention, the tool rake angle adjustment mechanism includes a base, a lever arm and a first high-precision adjustment screw, a tool is mounted on an end face of one end of the lever arm, and the lever arm is connected to the base via a first flexible hinge, a first preload spring for resetting the lever arm is mounted between the lever arm and the base, the first high-precision adjustment screw is mounted on the lever arm near the first preload spring, and is used to apply pressure to one end of the lever arm, thereby causing the first flexible hinge connected between the lever arm and the base to deform and drive the tool rake angle adjustment mechanism to rotate around the Y-axis.

[0008] In a preferred embodiment of the present invention, the first high-precision adjustment screw includes a knob and a first screw rod, wherein the first screw rod penetrates the lever arm and contacts the base.

[0009] In a preferred embodiment of the present invention, a limit block is further provided between the lever arm and the base for limiting the up and down displacement of the lever arm along the Z axis.

[0010] In a preferred embodiment of the present invention, the tool plane angle adjustment mechanism includes: a frame, a turntable connected to the middle of the frame through a second flexible hinge, a second high-precision adjustment screw connected to the turntable, and a second pre-tightening spring for providing horizontal support for the turntable, the tool front angle adjustment mechanism is installed on the turntable, and the second high-precision adjustment screw is used to apply a thrust to the turntable to cause the second flexible hinge connected to the turntable to deform and drive the turntable to rotate around the Z axis.

[0011] In a preferred embodiment of the present invention, there are at least three second flexible hinges, which are connected between the turntable and the frame at equal intervals.

[0012] In a preferred embodiment of the present invention, a boss is integrally connected to the side wall of the turntable, a stop block and a fixed block are provided on the frame, the second screw of the second high-precision adjustment screw passes through the fixed block and contacts the boss, and the second preload spring is provided between the boss and the stop block.

[0013] In a preferred embodiment of the present invention, the vertical lifting platform is fixed below the tool plane angle adjustment mechanism, and is controlled by a servo motor to drive the tool plane angle adjustment mechanism and the tool front angle adjustment mechanism to move up and down along the Z axis.

[0014] In a preferred embodiment of the present invention, the first flexible hinge and the second flexible hinge are elliptical flexible hinges.

[0015] The beneficial effects of the present invention are as follows: compared with the traditional tool holder adjustment system based on the cooperation of the sliding wedge block and the flexible hinge, the present invention eliminates the problem of slow release of static friction between the two sliding surfaces in the sliding system, thereby causing the tool position creep, and has higher precision. The present invention can achieve multi-degree-of-freedom adjustment of the tool rake angle, plane angle and tool height through the structural design of the tool rake angle adjustment mechanism, the tool plane angle adjustment mechanism and the vertical lifting platform, and has the characteristics of high adjustment precision, high efficiency and high rigidity. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a three-dimensional structural schematic diagram of a three-degree-of-freedom ultra-precision lathe tool holder adjustment system of the present invention;

[0017] Figure 2 yes Figure 1 The three-dimensional structural diagram of the tool rake angle adjustment mechanism shown;

[0018] Figure 3 yes Figure 1 The three-dimensional structural diagram of the tool plane angle adjustment mechanism shown;

[0019] The components in the accompanying drawings are marked as follows: 1. Tool front angle adjustment mechanism, 11. Base, 12. Lever arm, 13. First high-precision adjustment screw, 131. Knob, 132. First screw, 14. First flexible hinge, 15. First preload spring, 16. Tool, 17. Limit block; 2. Tool plane angle adjustment mechanism, 21. Frame, 22. Turntable, 221. Boss, 23. Second high-precision adjustment screw, 231. Knob, 232. Second screw, 24. Second flexible hinge, 25. Second preload spring, 26. Stop block, 27. Fixed block; 3. Vertical lifting platform. DETAILED DESCRIPTION

[0020] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the protection scope of the present invention.

[0021] See also Figure 1 , the embodiment of the present invention includes:

[0022] A three-degree-of-freedom ultra-precision lathe tool rest adjustment system includes: a tool rake angle adjustment mechanism 1, a tool plane angle adjustment mechanism 2 and a vertical lifting platform 3, wherein the tool rake angle adjustment mechanism 1 is installed on the tool plane angle adjustment mechanism 2, and can rotate around the Y axis to adjust the rake angle of the tool, the tool plane angle adjustment mechanism 2 is installed on the vertical lifting platform 3, and can rotate around the Z axis to adjust the plane angle of the tool, and the vertical lifting platform 3 can move up and down along the Z axis to adjust the height of the tool. That is, the tool rake angle adjustment mechanism 1, the tool plane angle adjustment mechanism 2 and the vertical lifting platform 3 can realize multi-degree-of-freedom adjustment of the tool rake angle, plane angle and tool height.

[0023] Continue to refer Figure 2 The tool rake angle adjustment mechanism 1 includes a base 11, a lever arm 12 and a first high-precision adjustment screw 13. A tool 16 is installed on the end surface of one end of the lever arm 12, and the end of the lever arm 12 on which the tool 16 is installed is connected to one end of the base 11 through a first flexible hinge 14. A first preload spring 15 is installed between the other end of the lever arm 12 and the other end of the base 11. The first preload spring 15 is used to reset the lever arm 12. The first high-precision adjustment screw 13 is installed on the lever arm 12 near the first preload spring 15, and is used to apply pressure to one end of the lever arm 12, so that the first flexible hinge 14 connected between the lever arm 12 and the base 11 is deformed to drive the tool rake angle adjustment mechanism 1 to rotate around the Y-axis, thereby realizing the adjustment of the tool rake angle.

[0024] Specifically, the first high-precision adjustment screw 13 includes a knob 131 and a first screw 132. The first screw 132 penetrates the lever arm 12 and contacts the base 11. The knob 131 is manually turned, and the first screw 132 applies pressure to the base 11, so that one end of the lever arm 12 moves up along the Z axis. At this time, the other end of the lever arm 12 is constrained by the first flexible hinge 14, forcing the first flexible hinge 14 to produce elastic deformation, so that the tool rake angle adjustment mechanism 1 rotates around the Y axis, thereby achieving adjustment of the tool rake angle.

[0025] Furthermore, a limit block 17 is fixed on the lever arm 12 , and the limit block is located between the lever arm 12 and the base 11 , and is used to limit the displacement of the lever arm 12 along the Z axis, prevent the lever arm 12 from excessive displacement, and avoid plastic deformation of the first flexible hinge 14 .

[0026] Continue to refer Figure 3The tool plane angle adjustment mechanism 2 includes: a frame 21, a turntable 22 connected to the middle part of the frame 21 through a second flexible hinge 24, a second high-precision adjustment screw 23 connected to the turntable 22, and a second preload spring 25 for resetting the turntable 22. The tool rake angle adjustment mechanism 1 is installed on the turntable 22. The second high-precision adjustment screw 23 is used to apply a thrust to the turntable 22, so that the second flexible hinge 24 connected to the turntable 22 produces elastic deformation, driving the turntable 22 to rotate around the Z axis, thereby realizing the adjustment of the plane angle of the tool.

[0027] Specifically, a boss 221 is integrally connected to the side wall of the turntable 22, and a stopper 26 and a fixing block 27 are also fixed to the frame 21. The second high-precision adjustment screw 23 includes a knob 231 and a second screw 232. The second screw 232 of the second high-precision adjustment screw 23 passes through the fixing block 27 and contacts the boss 221. The second preload spring 25 is fixed between the boss 221 and the stopper 26 to reset the boss 221. The knob 231 is manually turned, and the second screw 232 applies an X-direction thrust to the boss 221. At this time, the turntable 22 is constrained by the second flexible hinge 24 connected thereto, forcing the second flexible hinge 24 to produce elastic deformation, driving the turntable 22 to rotate around the Z-axis, thereby realizing the adjustment of the plane angle of the tool.

[0028] Preferably, there are at least three second flexible hinges 24 , which are connected between the turntable 22 and the frame 21 at equal intervals.

[0029] Continue to refer Figure 1 The vertical lifting platform 3 is fixed below the tool plane angle adjustment mechanism 2 and is controlled by a high-precision servo motor to drive the tool plane angle adjustment mechanism 2 and the tool front angle adjustment mechanism 1 to move up and down along the Z axis.

[0030] In this embodiment, the first flexible hinge 14 and the second flexible hinge 24 are both elliptical flexible hinges.

[0031] The first high-precision adjustment screw 13 and the second high-precision adjustment screw 23 are both nanometer-level high-precision adjustment screws with a thread density of not less than 170 TPI (Thread per Inch).

[0032] Next, continue to combine Figure 1 The working process of the three-degree-of-freedom ultra-precision lathe tool holder adjustment system includes the following steps:

[0033] A. First, the tool rake angle adjustment mechanism 1 at the top is controlled to rotate around the Y axis to adjust the tool rake angle;

[0034] B. Then, the tool plane angle is adjusted by controlling the middle tool plane angle adjustment mechanism 2 to rotate around the Z axis;

[0035] C. Finally, when the plane angle and rake angle of the tool meet the requirements, the tool height is adjusted by controlling the vertical lifting platform 3 at the bottom to move along the Z axis.

[0036] Among them, in step A, the front angle adjustment mechanism 1 based on a flexible hinge is used to rotate around the Y axis to achieve controllable adjustment of the angle of the tool front angle. After the front angle meets the requirements, step B is executed. The plane angle adjustment mechanism 2 based on a flexible hinge is used to rotate around the Z axis to achieve controllable adjustment of the angle of the tool plane angle. Through the cooperation of a high-precision manual threaded micron-level adjuster and a flexible hinge, the plane angle and front angle of the tool can be accurately and efficiently controlled.

[0037] In step C, after the tool plane angle and the front angle meet the requirements, the optical tool setting system is used to control the vertical lifting platform 3 at the bottom to adjust the height along the Z-axis direction using a high-precision servo motor. The height displacement resolution is less than 0.1µm. When the optical tool setting system is adjusted to the zero position, the preliminary tool setting in the Z and Y directions is completed.

[0038] Furthermore, in steps B and C, there is no coupling error between the rake angle adjustment and the plane angle adjustment. There is a unidirectional coupling error between the rake angle adjustment and the X-direction height adjustment. When the rake angle of the tool changes, the tool will be accompanied by a slight displacement in the X-direction. After the adjustment is completed through tool setting, the error can be eliminated by moving along the X-axis, realizing multi-dimensional high-precision tool setting, and compensating the machining accuracy based on the known tool plane angle, rake angle, tool tip arc radius, and tool tip arc center coordinates to reduce machining errors and meet the technical requirements of ultra-precision machining.

[0039] To sum up, the three-degree-of-freedom ultra-precision lathe tool holder adjustment system of the present invention can realize multi-degree-of-freedom adjustment of the tool rake angle, plane angle and tool height based on flexible hinges and high-precision servo motors, and has the characteristics of high adjustment accuracy, high efficiency and high rigidity.

[0040] Specifically, compared with the traditional tool holder adjustment system based on the cooperation of the sliding wedge block and the flexible hinge, the problem of slow release of static friction between the two sliding surfaces in the sliding system, which causes tool position creep, is eliminated, and higher precision is achieved; the tool angle adjustment mechanism based on the flexible hinge and the vertical lifting platform can realize multi-degree-of-freedom adjustment of the tool rake angle, plane angle and tool height, and the angle resolution can be less than 0.002° and the height displacement resolution can be less than 0.1µm. During the tool setting process, the processing error caused by insufficient tool setting accuracy is reduced, thereby achieving the purpose of high-precision tool setting.

[0041] In the description of the present invention, it should be noted that the terms "upper", "lower", "left", "right", "inside", "outside" and the like indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, or are directions or positional relationships in which the invented product is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention. The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

[0042] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A three-degree-of-freedom ultra-precision lathe tool holder adjustment system, characterized in that: include: A tool rake angle adjustment mechanism (1), a tool plane angle adjustment mechanism (2) and a vertical lifting platform (3), wherein the tool plane angle adjustment mechanism (2) is installed on the vertical lifting platform (3). The tool plane angle adjustment mechanism (2) comprises: a frame (21), a turntable (22) connected to the middle of the frame (21) via a second flexible hinge (24), a second high-precision adjustment screw (23) connected to the turntable (22), and a second preload spring (25) for resetting the turntable (22); the tool rake angle adjustment mechanism (1) is mounted on the turntable (22); the second high-precision adjustment screw (23) is used to apply a thrust to the turntable (22) so that the second flexible hinge (24) connected to the turntable (22) is deformed to drive the turntable (22) to move. The tool is rotated about the Z axis to adjust the plane angle of the tool, the second flexible hinges (24) are at least three and are connected between the turntable (22) and the frame (21) at equal intervals, a boss (221) is integrally connected to the side wall of the turntable (22), a stopper (26) and a fixing block (27) are provided on the frame (21), a second screw rod (232) of the second high-precision adjustment screw (23) passes through the fixing block (27) and contacts the boss (221), and the second preload spring (25) is provided between the boss (221) and the stopper (26), The vertical lifting platform (3) can move up and down along the Z axis to adjust the height of the tool; the vertical lifting platform (3) is fixed below the tool plane angle adjustment mechanism (2) and is controlled by a servo motor to drive the tool plane angle adjustment mechanism (2) and the tool front angle adjustment mechanism (1) to move up and down along the Z axis.

2. The three-degree-of-freedom ultra-precision lathe tool holder adjustment system according to claim 1, characterized in that: The tool rake angle adjustment mechanism (1) comprises a base (11), a lever arm (12) and a first high-precision adjustment screw (13); a tool (16) is mounted on an end surface of one end of the lever arm (12); the lever arm (12) is connected to the base (11) via a first flexible hinge (14); a first preload spring (15) for resetting the lever arm (12) is mounted between the lever arm (12) and the base (11); the first high-precision adjustment screw (13) is mounted on the lever arm (12) near the first preload spring (15) and is used to apply pressure to one end of the lever arm (12), thereby causing the first flexible hinge (14) connected between the lever arm (12) and the base (11) to deform and drive the tool rake angle adjustment mechanism (1) to rotate around the Y axis.

3. The three-degree-of-freedom ultra-precision lathe tool holder adjustment system according to claim 2, characterized in that: The first high-precision adjustment screw (13) comprises a knob (131) and a first screw rod (132), wherein the first screw rod (132) penetrates the lever arm (12) and contacts the base (11).

4. The three-degree-of-freedom ultra-precision lathe tool holder adjustment system according to claim 2, characterized in that: A limit block (17) is also provided between the lever arm (12) and the base (11) for limiting the vertical displacement of the lever arm (12) along the Z axis.

5. The three-degree-of-freedom ultra-precision lathe tool rest adjustment system according to any one of claims 2 to 4, characterized in that: The first flexible hinge (14) and the second flexible hinge (24) are elliptical flexible hinges.

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