An adaptive vibration suppression method based on particle damping

Abstract

The present invention relates to the technical field of vibration suppression of cutting tools, and specifically to a device based on particle damping vibration suppression and an adaptive vibration suppression method. The present invention can effectively suppress the chattering phenomenon of the tool during the processing, and realize the suppression of tool chatter in a wide frequency band; the tool vibration energy is consumed by the collision and friction between particles and particles and cavities, and the amplitude is reduced, thereby reducing the risk of chattering and improving the cutting quality and processing accuracy; it can effectively reduce the tool wear and breakage caused by chattering, extend the service life of the tool, reduce the frequency of tool replacement, and thus reduce costs; the application of the particle damping technology of the present invention provides a new method for tool chatter suppression, and realizes wide-band vibration suppression of the tool through a simple particle damper device, which helps to improve the stability of the cutting process and the surface processing quality, and has broad application prospects in related fields such as cutting, tool design and process optimization.

Description

Technical Field

[0001] The invention relates to the technical field of vibration suppression of cutting tools, and in particular to an adaptive vibration suppression method based on particle damping. Background Art

[0002] During the cutting process, when chatter occurs, it will lead to a decrease in processing efficiency and processing accuracy, and the product will not meet the standards or even be scrapped. How to suppress vibration during the processing is a major problem that plagues researchers. It is directly related to the safety, processing quality, tool life and processing efficiency of the cutting process. The cutting system stiffness, cutting parameters, tool condition, workpiece condition, etc. in the cutting process may cause chatter or processing resonance. Moreover, the tool chatter frequency is not single and it is difficult to suppress the tool tip vibration through traditional tuned mass dampers under high speed conditions. Therefore, wide-band vibration reduction in the cutting process has always been a problem, which brings inconvenience to the cutting process. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a tool holder device and an adaptive vibration suppression method for suppressing tool tip vibration by particle damping technology, so as to suppress chatter during cutting processing.

[0004] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0005] ① The present invention comprises a tool handle body, a particle damper, a particle damper mounting nut, a particle damper connecting thread, a partition, an upper cavity, and a lower cavity; the particle damper is divided into a cavity part and a connecting part, and is composed of two parts stacked concentrically; the cavity part is composed of an upper cavity and a lower cavity connected up and down, and separated by a partition; the connecting part comprises a particle damper connecting thread; the particle damper mounting nut and the particle damper connecting thread are threadedly connected to connect the tool handle body to the particle damper.

[0006] The device of the present invention is used to implement the adaptive vibration suppression method, and the steps are as follows:

[0007] ② The particle damper is equivalent to a subsystem with only a viscous damper and mass. The dynamic equation of the system can be written as:

[0008]

[0009] Where m1 is the tool mass; m2 includes the tool handle mass, the particle damping cavity mass and the mass of particles attached to the particle damping cavity that do not participate in motion energy consumption; m3 is the mass of particles that participate in motion energy consumption; k1 is the tool stiffness; c1 is the tool damping coefficient; k2 is the tool handle stiffness; c2 is the tool handle damping coefficient; c eqis the damping coefficient of the mass of the particles involved in the motion; it can be organized into a matrix form as follows:

[0010]

[0011] ③Further written in frequency domain form:

[0012]

[0013] ④ The tool displacement frequency response function can be derived from formula (III):

[0014]

[0015] ⑤The values ​​of m2 and m3 are affected by the vibration acceleration of the tool and change with the vibration acceleration, but the sum of the two is a constant value and satisfies the following formula:

[0016] m2+m3=m c +m p (five);

[0017] Where m c is the weight of the tool holder and particle damping chamber, m p is the total mass of the damping particles; the particle mass dynamic distribution scheme adopts the following formula:

[0018]

[0019] ⑥ Based on the damping ratio definition of the single degree of freedom system, the calculation formula of the equivalent damping coefficient is as follows:

[0020]

[0021] ⑦ Implement steps ① to ⑥, and adjust the frequency response function of formula (IV) by adjusting the number and type of particles.

[0022] The present invention also includes an upper cavity particle filling hole and a lower cavity particle filling hole; the lower cavity particle filling hole is located at the bottom center of the lower cavity; the top of the upper cavity has three or more evenly distributed holes as the upper cavity particle filling holes; the filling particles are alloy copper or tungsten steel spherical particles.

[0023] The particle damper is manufactured by 3D printing of TC4 titanium alloy material; the radius of the cavity part is 14mm, the height is 54mm, the wall thickness is 1mm, and the middle partition between the upper cavity and the lower cavity is 1mm.

[0024] The radius of the particle filling hole of the lower cavity is 2mm, and the radius of the particle filling hole of the upper cavity is 1.25mm; the diameter of the connecting thread part is 8mm and the length is 28mm, and an M8 particle damper connecting thread with a length of 18mm is set at the overhanging end of the connecting thread.

[0025] The alloy copper or tungsten steel particles are filled with 1665 particles respectively, the lower cavity is closed with tape, and the upper cavity does not need to be specially closed.

[0026] The positive effects of the present invention are as follows: the present invention discloses an implementation method for suppressing tool tip chatter using particle damping technology, as well as specific size parameters of particle dampers, alloy copper particle sizes and filling quantities; the present invention can effectively suppress the chatter phenomenon of a tool during machining, and achieve tool chatter suppression in a wide frequency band; the present invention consumes tool vibration energy through collision and friction between particles and between particles and cavities, reduces the amplitude, thereby reducing the risk of chatter and improving cutting quality and machining accuracy; the present invention increases the damping characteristics of the tool system, improves the stability of the cutting process, and helps to reduce the amplitude and frequency of tool vibration; the present invention effectively reduces tool wear and breakage caused by chatter, extends the service life of the tool, reduces the frequency of tool replacement, and thus reduces costs; the present invention effectively reduces noise and vibration caused by tool vibration, provides a more stable and safe working environment, reduces health risks to operators and the occurrence of industrial accidents, and has important application value in the field of tool machining; the application of the particle damping technology of the present invention provides a new method for tool chatter suppression, and achieves tool broadband vibration suppression through a simple particle damper device, which helps to improve the stability of the cutting process and the surface machining quality, and has broad application prospects in related fields such as cutting machining, tool design and process optimization. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0028] Figure 1 It is an exploded view of the installation of the particle damper of the tool handle of the present invention;

[0029] Figure 2 It is a schematic diagram of the structure of the particle damper of the tool handle of the present invention;

[0030] Figure 3 is a cross-sectional view of a particle damper for a tool handle according to the present invention;

[0031] Figure 4 It is a schematic diagram of the dynamic model of the particle damper of the present invention;

[0032] Figure 5 This is the effect diagram of particle damper on the frequency response function of tool system;

[0033] Figure 6This is a partial enlarged diagram of the influence of the particle damper on the frequency response function of the tool system.

[0034] In the figure: 1 handle body, 8 particle damper, 801a particle damper mounting nut, 801b particle damper connecting thread, 802 upper cavity particle filling hole, 803 lower cavity particle filling hole, 804 partition, 805 upper cavity, 806 lower cavity. DETAILED DESCRIPTION

[0035] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0036] Establish the intelligent tool handle device characterizing the present invention:

[0037] like Figure 1 As shown, the tool handle vibration suppression device is composed of a tool handle body 1, a particle damper 8, and a particle damper mounting nut 801a. The tool handle body model is HSK63A-ER40-160L. The particle damper 8 is connected to the tool handle body 1 through the particle damper mounting nut 801a.

[0038] Implementation method of particle damping to suppress flutter in the present invention:

[0039] The particle damper device for suppressing the vibration of the tool tip is as follows: Figure 1-3 As shown. Based on the particle damping energy dissipation mechanism, the device realizes the vibration suppression of the tool tip by setting the particle damper 8 inside the tool handle. The specific implementation method is to fill 1665 alloy copper particles with a radius of 1mm into the particle damper 8 from the particle filling hole 802 of the upper cavity 805 and the particle filling hole 803 of the lower cavity 806, respectively, and install it inside the tool handle through the particle damper connecting thread 801b and the particle damper mounting nut 801a on the extended part of the particle damper 8. The particle damper 8 is made of TC4 titanium alloy substrate by 3D printing, as shown in FIG. Figure 3 The interior of the particle damper 8 is divided into upper and lower cavities of equal volume by partition 804. When the tool generates chatter, the particles inside the particle damper 8 will interact violently with the wall surface, thereby inducing interaction between the internal particles, and the energy generated by the vibration is consumed by collision and friction between particles and particles and the damper wall surface to achieve the effect of suppressing chatter, thereby improving the surface quality of the workpiece.

[0040] As attached Figure 4The dynamic model shown in the figure is used to perform dynamic analysis on the tool handle system containing the particle damper, and an equivalent particle damper model is established. In order to approximately describe the macroscopic collective effect of many damping particles, a subsystem with only one viscous damper and mass is used inside the container to equivalent the dynamic behavior of many particles under a given acceleration. The dynamic equation of the system can be written as:

[0041]

[0042] Where m1 is the mass of the tool; m2 is the mass including the mass of the tool handle, the mass of the particle damping cavity and the mass of the particles attached to the particle damping cavity that do not participate in the motion energy consumption; m3 is the mass of the particles that participate in the motion energy consumption; k1 is the tool stiffness; c1 is the tool damping coefficient; k2 is the tool handle stiffness; c2 is the tool handle damping coefficient; c eq is the damping coefficient of the mass of the particles involved in the motion; it can be organized into a matrix form as follows:

[0043]

[0044] Further written in frequency domain form:

[0045]

[0046] The tool displacement frequency response function can be derived from the above formula:

[0047]

[0048] The values ​​of m2 and m3 are affected by the vibration acceleration of the tool and change with the vibration acceleration, but the sum of the two is a constant value and satisfies the following formula:

[0049] m2+m3=m c +m p (five);

[0050] Where m c is the weight of the tool holder and particle damping chamber, m p is the total mass of the damping particles; m3 reflects the energy consumption of the particle damper to a certain extent. If the equivalent damping ratio ζ eq is very small, indicating that only a few particles move relative to each other, that is, m3 is very small, and most of the particle mass is attached to the cavity (m2 is large); on the contrary, if ζ eq If it is larger, it means that a lot of particles are involved in relative motion. The mass of particles attached to the cavity will be less; based on this basic physical common sense, the following particle mass dynamic distribution scheme can be used to simply approximate m2 and m3;

[0051]

[0052] Since it is difficult to find the relationship between the equivalent damping coefficient and the system parameters, the definition of the damping ratio of the single-degree-of-freedom system is used to obtain the calculation formula of the equivalent damping coefficient as follows:

[0053]

[0054] The frequency response function in formula (IV) can be controlled by adjusting the number and type of particles.

[0055] Given a set of structural parameter values, m1 = 0.123 kg, m c =2kg,m p =0.3kg, k1=1.26×10 7 N / m, k2=5.0×10 7 N / m, ζ1=0.012, ζ2=0.01; calculate the tool frequency response function as shown in the attached Figures 5-6 As shown in the figure. It can be seen from the graph that the peak value of the system decreases proportionally, and no matter how large the damping is, the performance of the particle damper is not affected and still works. This is a feature that traditional viscous damping systems do not have. Because the particle damper is not in direct contact with the main structure, no matter how large the damping is, the particle damper will not fail, but will consume more energy in the system. This is an important feature of the particle damper.

[0056] The above-described embodiments are only preferred embodiments of the present invention, and are not exhaustive of the feasible implementations of the present invention. For those skilled in the art, any obvious changes made thereto without departing from the principles and spirit of the present invention should be considered to be included in the scope of protection of the claims of the present invention.

Claims

1. An adaptive vibration suppression method based on particle damping, characterized in that: Here are the steps: ① The particle damping vibration suppression device comprises: a tool handle body (1), a particle damper (8), a particle damper mounting nut (801a), a particle damper connecting thread (801b), a partition (804), an upper cavity (805), and a lower cavity (806); the particle damper (8) is divided into a cavity part and a connecting part, and is composed of two parts stacked concentrically; the cavity part is composed of an upper cavity (805) and a lower cavity (806) connected up and down, and separated by a partition (804); the connecting part comprises a particle damper connecting thread (801b); the particle damper mounting nut (801a) and the particle damper connecting thread (801b) are connected to the tool handle body (1) and the particle damper (8) through threaded connection; ② The particle damper (8) is equivalent to a subsystem with only a viscous damper and mass. The dynamic equation of the system is: Where m1 is the tool mass; m2 includes the tool handle mass, the particle damping cavity mass and the mass of particles attached to the particle damping cavity that do not participate in motion energy consumption; m3 is the mass of particles that participate in motion energy consumption; k1 is the tool stiffness; c1 is the tool damping coefficient; k2 is the tool handle stiffness; c2 is the tool handle damping coefficient; c eq is the damping coefficient of the mass of particles involved in the motion; ③ Arrange formula (1) into a matrix form: Further written in frequency domain form: ④ The tool displacement frequency response function is derived from formula (III): ⑤The values ​​of m2 and m3 are affected by the vibration acceleration of the tool and change with the vibration acceleration, but the sum of the two is a constant value and satisfies the following formula: m2+m3=m c +m p (five); Where m c is the weight of the tool holder and particle damping chamber, m p is the total mass of the damping particles; the particle mass dynamic distribution scheme adopts the following formula: ⑥The damping ratio of the single degree of freedom system is defined, and the calculation formula of the equivalent damping coefficient is as follows: ⑦ Implement steps ① to ⑥, and adjust the frequency response function of formula (IV) by adjusting the number and type of particles.

2. The adaptive vibration suppression method based on particle damping according to claim 1, characterized in that: It also includes an upper cavity particle filling hole (802) and a lower cavity particle filling hole (803); the lower cavity particle filling hole (803) is located at the bottom center of the lower cavity; the top of the upper cavity (805) has three or more evenly distributed holes which are the upper cavity particle filling holes (802); the filling particles are alloy copper or tungsten steel spherical particles.

3. The adaptive vibration suppression method based on particle damping according to claim 2, characterized in that: The particle damper (8) is manufactured by 3D printing of TC4 titanium alloy material; the radius of the cavity part is 14 mm, the height is 54 mm, the wall thickness is 1 mm, and the middle partition between the upper cavity (805) and the lower cavity (806) is 1 mm.

4. The adaptive vibration suppression method based on particle damping according to claim 2, characterized in that: The radius of the lower cavity particle filling hole (803) is 2 mm, and the radius of the upper cavity particle filling hole (802) is 1.25 mm; the diameter of the connecting thread part is 8 mm and the length is 28 mm, and an M8 particle damper connecting thread (801b) with a length of 18 mm is set at the overhanging end of the connecting thread.

5. The adaptive vibration suppression method based on particle damping according to claim 2, characterized in that: The alloy copper or tungsten steel particles are filled with 1665 particles respectively, and the lower cavity (806) is sealed with tape, while the upper cavity (805) does not need to be specially sealed.

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