High-precision adaptive main shaft dynamic balancing device and adaptive dynamic balancing adjustment method

Abstract

High-precision adaptive main shaft dynamic balance device and adaptive dynamic balance adjustment method belong to the technical field of ultra-precision equipment. The inner hole of the dynamic balance seat is in high-precision cooperation with the rear end of the air static pressure spindle, the right end of the dynamic balance seat is provided with an annular groove, metal suspension liquid is injected into the annular groove, a sealing cover is used for sealing the annular groove, and a locking nut is used for fixing the dynamic balance seat and the air static pressure spindle. The application realizes automatic dynamic balance of the air static pressure spindle, the annular groove of the application adopts a special rotary structure and a specific proportion of metal suspension liquid, so that the air static pressure spindle can automatically eliminate its dynamic unbalance amount when rotating, not only avoiding the cumbersome operation during micro dynamic balance adjustment, but also further improving the dynamic balance precision of the air static pressure spindle. The application breaks through the precision limit of the current air static pressure spindle dynamic balance, and provides a technical basis for further improving the performance of the spindle. High-precision taper cooperation is adopted to ensure the repeated clamping precision of the device.

Description

Technical Field

[0001] This invention belongs to the field of ultra-precision equipment technology, specifically relating to a high-precision adaptive spindle dynamic balancing device and an adaptive dynamic balancing adjustment method. Background Technology

[0002] Ultra-precision air-static spindles are equipped with high-precision, low-friction air-static bearings, giving them excellent characteristics of high rotational accuracy and high speed, making them widely used in ultra-precision machining and ultra-precision inspection. With the development of these fields, increasingly higher demands are being placed on this type of spindle. When an air-static spindle rotates at high speed, uneven mass distribution of rotating components will generate dynamic imbalance, further causing spindle vibration. This not only affects the spindle's performance but can even cause permanent damage to spindle components. Therefore, air-static spindles require dynamic balancing before use to improve their accuracy and safety.

[0003] Currently, the dynamic balancing of air static pressure spindles mainly relies on trial weights. However, this method is limited by the accuracy of the dynamic balancing testing equipment and the influence of the weight error of the balance weight during adjustment. The minimum imbalance error can be controlled within 20mg. Furthermore, spindle dynamic balancing requires repeated attempts for minor adjustments, which is time-consuming and labor-intensive. To further improve the dynamic balancing accuracy of air static pressure spindles, new dynamic balancing devices and methods need to be developed to overcome the accuracy limitations of both the testing and adjustment processes. Summary of the Invention

[0004] In order to overcome the shortcomings of the prior art, the present invention provides an adaptive dynamic balancing device and an adaptive dynamic balancing adjustment method that can improve the dynamic balancing accuracy of the spindle.

[0005] The technical solution adopted in this invention is:

[0006] A high-precision adaptive spindle dynamic balancing device includes a dynamic balancing seat, a metal suspension, a sealing cover, and a locking nut. The inner hole of the dynamic balancing seat is precisely fitted to the rear end of the air static pressure spindle. An annular groove is opened at the right end of the dynamic balancing seat, and the metal suspension is injected into the annular groove. The sealing cover is fixedly connected to the dynamic balancing seat to seal the annular groove. The locking nut is connected to the air static pressure spindle to fix the dynamic balancing seat to the air static pressure spindle.

[0007] The adaptive dynamic balancing adjustment method for a high-precision adaptive spindle dynamic balancing device includes the following steps:

[0008] S1. Install the dynamic balancing device on the air static pressure spindle and connect the air static pressure spindle to the dynamic balancing instrument;

[0009] S2. Perform preliminary dynamic balancing using balance weights;

[0010] S3. Inject a metal suspension into the annular groove of the dynamic balance seat;

[0011] S4. Start the air static pressure spindle to complete the adaptive dynamic balance adjustment.

[0012] Compared with the prior art, the present invention has the following advantages:

[0013] This invention achieves automatic dynamic balancing of air hydrostatic spindles. The annular groove of this invention employs a special rotary structure and a specifically proportioned metal suspension, enabling the air hydrostatic spindle to automatically eliminate its own dynamic imbalance during rotation. This not only avoids the tedious operations of minute dynamic balancing adjustments but also further improves the dynamic balancing accuracy of the air hydrostatic spindle. The method of this invention breaks through the current accuracy limits of dynamic balancing for air hydrostatic spindles, providing a technical foundation for further performance improvements in this type of spindle.

[0014] Furthermore, the device of the present invention adopts a high-precision conical surface mating method to ensure the repeatability of the device's clamping accuracy, so that it meets the range of spindle adaptive dynamic balance adjustment before and after each assembly and disassembly. Attached Figure Description

[0015] Figure 1 This is an overall schematic diagram of the invention;

[0016] Figure 2 This is an exploded isometric view of the present invention;

[0017] Figure 3 This is a front view of the dynamic balance seat of the present invention;

[0018] Figure 4 This is an isometric drawing of the dynamic balance seat of this invention;

[0019] Figure 5 This is a schematic diagram of the principle of adaptive adjustment of spindle dynamic balance in this invention;

[0020] The components are: 1. Air static pressure spindle; 2. Dynamic balance seat; 3. Metal suspension; 4. Sealing cover; 5. Locking nut; 1-1. Contact surface one; 2-1. Dynamic balance hole; 2-2. Contact surface two; 2-3. Contact surface three; 2-4. Annular groove; 4-1. Contact surface four. Detailed Implementation

[0021] To better understand the purpose, structure, and function of this invention, the invention will be described in further detail below with reference to the accompanying drawings.

[0022] like Figures 1-5As shown, a high-precision adaptive spindle dynamic balancing device of the present invention includes a dynamic balancing seat 2, a metal suspension 3, a sealing cover 4, and a locking nut 5. The inner hole of the dynamic balancing seat 2 is precisely fitted with the rear end of the air static pressure spindle 1. An annular groove 2-4 is opened at the right end of the dynamic balancing seat 2, and the metal suspension 3 is injected into the annular groove 2-4. The sealing cover 4 is fixedly connected to the dynamic balancing seat 2 by screws to seal the annular groove 2-4. The locking nut 5 is threadedly connected to the tail end of the air static pressure spindle 1 and contacts the right side of the dynamic balancing seat 2 to fix the dynamic balancing seat 2 and the air static pressure spindle 1.

[0023] like Figure 3 , Figure 4 As shown, near the outer circle of the end face of the dynamic balance seat 2, there are multiple dynamic balance holes 2-1 evenly distributed, preferably 12, and multiple protrusions evenly distributed on the annular groove 2-4, staggered from the dynamic balance holes 2-1, preferably 12. The dynamic balance holes 2-1 and the annular groove 2-4 are used for coarse adjustment of the spindle dynamic balance and adaptive adjustment of dynamic balance under high precision, respectively.

[0024] like Figure 1 , Figure 4 As shown, the contact surface 2-2 of the dynamic balance seat 2 and the contact surface 1-1 of the air static pressure spindle 1 are a pair of high-precision conical surfaces, with a roundness error of <1μm and a cone angle error of <0.01°.

[0025] like Figure 2 , Figure 3 As shown, the contact surface 2-3 of the dynamic balance seat 2 and the contact surface 4-1 of the sealing cover 4 are both high-precision planes. The flatness error of both planes is <1μm and the surface roughness Ra is <0.1μm.

[0026] The metal suspension 3 is composed of 30% tungsten powder and 70% mineral oil.

[0027] The adaptive dynamic balancing adjustment method for a high-precision adaptive spindle dynamic balancing device includes the following steps:

[0028] S1. Press Figure 1 Install the dynamic balancing device on the air static pressure spindle 1, and connect the air static pressure spindle 1 to the dynamic balancing instrument;

[0029] S2. Perform preliminary dynamic balancing using balance weights;

[0030] Start the air static pressure spindle 1 until it reaches the working speed. After the dynamic balancing instrument displays the measurement results, stop the air static pressure spindle 1 and add balance blocks at the corresponding positions of the multiple dynamic balancing holes 2-1 on the dynamic balancing seat 2.

[0031] S3. Inject metal suspension 3 into the annular groove 2-4 of the dynamic balance seat 2;

[0032] Repeat step S2 until the dynamic balancing instrument displays a dynamic imbalance of <50mg for the air static pressure spindle 1. Mark the relative position of the dynamic balancing seat 2 and the air static pressure spindle 1. Remove the dynamic balancing seat 2 and open the sealing cover 4. Inject the metal suspension 3 into the annular groove 2-4. The volume of the metal suspension 3 should be half the space of the annular groove 2-4. Then, according to... Figure 1 Re-fix and install the dynamic balancing device.

[0033] S4. Start the air static pressure spindle 1 with an acceleration a≤50rpm / s2. After the air static pressure spindle 1 reaches the working speed, wait 3-5 minutes to complete the adaptive dynamic balance adjustment.

[0034] like Figure 5 As shown, when the air static pressure spindle 1 rotates, due to uneven mass distribution, it is subjected to centrifugal force generated by the inertia of unbalanced mass. The formula is:

[0035]

[0036] in: Let m be the centrifugal force vector, and m be the unbalanced mass. Let ω be the eccentricity of the unbalanced mass, and ω be the spindle speed.

[0037] When the air static pressure main shaft 1 is subjected to centrifugal force After that, a tiny displacement will occur at the corresponding position. The displaced annular grooves 2-4, as shown Figure 5 As shown by the dashed line, at this point, part of the metal suspension 3 at the displacement location will detach from the annular groove 2-4 and distribute to other positions. Due to the separation of the suspension, the weight at the displacement location is reduced, thus decreasing the centrifugal force and the offset of the main shaft. After multiple main shaft offsets, suspension detachments, and redistributions, the air hydrostatic main shaft 1 finally reaches a stable state, at which point the mass distribution is most uniform and the displacement is minimal, thus completing the adaptive adjustment of dynamic balance.

[0038] The advantage of this invention is that, through the specially structured dynamic balancing annular groove 2-4 and the metal suspension 3 with a specific ratio, high-precision adaptive dynamic balancing adjustment of the air static pressure spindle 1 can be achieved. This not only avoids the cumbersome operation of previous high-precision dynamic balancing adjustments, but also breaks through the current limit of spindle dynamic balancing accuracy.

[0039] Furthermore, this invention specifies the accuracy requirements for the spindle adaptive dynamic balancing device. The device of this invention adopts a high-precision conical surface mating method to ensure the repeatability of the device's clamping accuracy, so that it meets the adjustment range of adaptive dynamic balancing before and after each assembly and disassembly.

[0040] It is understood that the present invention has been described through some embodiments, and those skilled in the art will recognize that various changes or equivalent substitutions can be made to these features and embodiments without departing from the spirit and scope of the invention. Furthermore, under the teachings of the present invention, these features and embodiments can be modified to adapt to specific situations and materials without departing from the spirit and scope of the invention. Therefore, the present invention is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are within the protection scope of the present invention.

Claims

1. A high-precision adaptive spindle dynamic balancing device, characterized in that: The system includes a dynamic balance seat (2), a metal suspension (3), a sealing cover (4), and a locking nut (5). The inner hole of the dynamic balance seat (2) is precisely fitted to the rear end of the air static pressure spindle (1). An annular groove (2-4) is opened at the right end of the dynamic balance seat (2), and the metal suspension (3) is injected into the annular groove (2-4). The sealing cover (4) is fixedly connected to the dynamic balance seat (2) to seal the annular groove (2-4). The locking nut (5) is connected to the air static pressure spindle (1) to fix the dynamic balance seat (2) to the air static pressure spindle (1). The end face of the dynamic balancing seat (2) near the outer circle has multiple dynamic balancing holes (2-1) evenly distributed, and the annular groove (2-4) is provided with multiple protrusions evenly distributed and staggered from the dynamic balancing holes (2-1). The dynamic balancing holes (2-1) and the annular groove (2-4) are used for coarse adjustment of the spindle dynamic balance and adaptive adjustment of dynamic balance under high precision, respectively. The metal suspension (3) is composed of 30% tungsten powder and 70% mineral oil.

2. The high-precision adaptive spindle dynamic balancing device according to claim 1, characterized in that: The contact surface 2 (2-2) of the dynamic balance seat (2) and the contact surface 1 (1-1) of the air static pressure spindle (1) are a pair of high-precision conical surfaces with a roundness error of <1μm and a cone angle error of <0.01°.

3. The high-precision adaptive spindle dynamic balancing device according to claim 1, characterized in that: The contact surface three (2-3) of the dynamic balance seat (2) and the contact surface four (4-1) of the sealing cover (4) are both high-precision planes, with a flatness error of <1μm and a surface roughness Ra of <0.1μm.

4. An adaptive dynamic balancing adjustment method using the high-precision adaptive spindle dynamic balancing device according to any one of claims 1 to 3, characterized in that: Includes the following steps: S1. Install the dynamic balancing device on the air static pressure spindle (1) and connect the air static pressure spindle (1) to the dynamic balancing instrument; S2. Perform preliminary dynamic balancing using balance weights; S3. Inject metal suspension (3) into the annular groove (2-4) of the dynamic balance seat (2); S4. Start the air static pressure spindle (1) and complete the adaptive dynamic balance adjustment.

5. The adaptive dynamic balancing adjustment method of the high-precision adaptive spindle dynamic balancing device according to claim 4, characterized in that: The specific operation of the preliminary dynamic balancing adjustment by the balance block in S2 is as follows: start the air static pressure spindle (1) until it reaches the working speed, wait for the dynamic balancing instrument to display the measurement result, stop the air static pressure spindle (1), and add balance blocks at the corresponding positions of multiple dynamic balancing holes (2-1) on the dynamic balancing seat (2).

6. The adaptive dynamic balancing adjustment method of the high-precision adaptive spindle dynamic balancing device according to claim 5, characterized in that: The specific operation of S3 is as follows: repeat step S2 until the dynamic balancer shows that the dynamic imbalance of the air static pressure spindle (1) is <50 mg, mark the relative position of the dynamic balance seat (2) and the air static pressure spindle (1), remove the dynamic balance seat (2) and open the sealing cover (4), inject the metal suspension (3) into the annular groove (2-4), and then re-fix and install the dynamic balance device.

7. The adaptive dynamic balancing adjustment method of the high-precision adaptive spindle dynamic balancing device according to claim 6, characterized in that: In S3, the volume of the metal suspension (3) is half the space of the annular groove (2-4).

8. The adaptive dynamic balancing adjustment method of the high-precision adaptive spindle dynamic balancing device according to claim 6, characterized in that: The specific operation of S4 is as follows: start the air static pressure spindle (1), with an acceleration a≤50rpm / s2, and wait for 3-5 minutes after the air static pressure spindle (1) reaches the working speed to complete the adaptive dynamic balance adjustment.

Images