阅读说明：本技术 一种高速主轴机械式动平衡装置质量补偿优化方法 (Mass compensation optimization method for high-speed spindle mechanical dynamic balance device ) 是由 王展 张博 涂伟 张珂 于 2019-11-21 设计创作，主要内容包括：本发明提出了一种高速主轴机械式动平衡装置质量补偿优化方法,首先建立出高速主轴机械式动平衡装置中的机械式平衡头中的两个配重块在极坐标下移动的角度的数学建模,然后将该数学模型作为遗传算法的适应度函数,对两个配重块的移动策略进行优化,得到优化后的配重块A、B在极坐标下的移动角度值,最后根据优化得到的移动角度值移动两个配重块,达到消除主轴的初始不平衡量的目的。本发明提高了机械主轴平衡效率,提升了平衡精度,对减小设备噪声、降低损耗、延长使用寿命、保证安全生产方面意义重大,同时也为高速机械主轴在线动平衡调控策略提供了基础和依据,具有一定的工程应用价值。(The invention provides a quality compensation optimization method for a high-speed spindle mechanical dynamic balancing device, which comprises the steps of firstly establishing mathematical modeling of the moving angle of two balancing weights in a mechanical balancing head in the high-speed spindle mechanical dynamic balancing device under a polar coordinate, then taking the mathematical model as a fitness function of a genetic algorithm, optimizing the moving strategy of the two balancing weights to obtain an optimized moving angle value of the balancing weight A, B under the polar coordinate, and finally moving the two balancing weights according to the optimized moving angle value to achieve the purpose of eliminating the initial unbalance amount of a spindle. The invention improves the balance efficiency of the mechanical main shaft, improves the balance precision, has great significance in reducing equipment noise, reducing loss, prolonging service life and ensuring safe production, simultaneously provides basis and basis for the online dynamic balance regulation and control strategy of the high-speed mechanical main shaft, and has certain engineering application value.)

1. A mass compensation optimization method for a high-speed spindle mechanical dynamic balance device is characterized by comprising the following steps:

step 1: running the main shaft at the expected rotating speed for experiment to obtain experiment data parameters, wherein the experiment data parameters comprise the initial phase theta 'of the balancing weight A in the mechanical balance head'_AInitial phase θ 'of weight B in mechanical balance head'_BCentrifugal force F of counterweight A at desired speed₁Centrifugal force F of weight B at desired speed₂；

Step 2: establishing mathematical modeling for the moving angle of two balancing weights in a mechanical balancing head in the high-speed spindle mechanical dynamic balancing device under polar coordinates;

and step 3: taking the established mathematical model of the movement angle of the counterweight blocks as a fitness function of a genetic algorithm, optimizing the movement strategies of the two counterweight blocks to obtain the movement angle value of the optimized counterweight block A under a polar coordinate

And 4, step 4: moving the balancing weight A by the angle value under the polar coordinate

2. The method for optimizing the mass compensation of the high-speed spindle mechanical dynamic balance device according to claim 1, wherein the mathematical model established in the step 2 is expressed as:

in the formula (I), the compound is shown in the specification,

3. The method for optimizing the mass compensation of the high-speed spindle mechanical dynamic balance device according to claim 1, wherein the step 3 is specifically expressed as:

3.1) random generation of N groups by computer

3.2) calculating the corresponding initial solution of the jth group in the mth iteration

3.3) converting the j-th group of initial solutions in the m-th iteration reserved in the step 3.2) into binary systems, and obtaining the latest solution through cross variation, wherein the cross operation is that each bit in two adjacent binary series has a preset probability P₁Randomly exchanging and randomly selecting the position of the exchange, the mutation operation is that each bit in the binary number sequence has a preset probability P₂Converting, namely converting the bit of 0 into 1 and converting the bit of 1 into 0;

3.4) taking the latest solution obtained in the step 3.3) as an initial solution of the (m + 1) th iteration, making m equal to m +1, returning to the step 3.2) for iterative calculation, and taking a result after H iterations as a final solution;

3.5) converting the final solution obtained in the step 3.4) into decimal output which is used as the moving angle value of the two optimized balancing weights under the polar coordinate

4. The method for optimizing the mass compensation of the high-speed spindle mechanical dynamic balance device according to claim 3, wherein the step 3.2) is specifically expressed as:

3.2.1) calculate the probability p that the jth initial solution can be retained using equation (2)_j,m：

In the formula (I), the compound is shown in the specification,

3.2.2) calculating each p by using the formula (3)_j,mCumulative probability of (q)_j,m：

In the formula (p)_j,m)_lRepresenting the probability p that the ith calculation is retained in the mth iteration_j,mM represents the retained probability p calculated from the N initial solutions at the mth iteration_j,mThe total number of times;

3.2.3) in [0,1]Generating a random number r within the interval, if r<q_j,mAnd if not, eliminating the jth initial solution.

Technical Field

The technology relates to the technical field of high-speed spindle on-line dynamic balance, in particular to a mass compensation optimization method for a high-speed spindle mechanical dynamic balance device.

Background

The main shaft system is a core component of the numerical control machine tool, the running quality of the main shaft system determines the performance of the numerical control machine tool, but the main shaft system can generate mass imbalance due to the influence of factors such as load, impact, abrasion deformation and the like in the working process, so that the vibration of the machine tool is aggravated, and the machining precision of the machine tool is seriously influenced. Therefore, the research on the online dynamic balance technology of the spindle system has important theoretical and practical significance.

A large amount of researches on an online dynamic balance regulation and control method and a mass compensation strategy of a main shaft type rotor system are carried out at home and abroad. The standing aromatic provides the criterion and the judgment principle of the optimal movement of the balancing weight; the summarized error-free control algorithm for the double-counterweight balance head can effectively improve the automatic balance quality, so that the motor-driven double-counterweight balance head has no error adjustment, no oscillation and short balance time. The Cao improves the double-balancing disk movement control strategy which can rotate randomly relative to the positive and negative directions of the rotating shaft; the method provides a solution for two special conditions, and effectively improves the automatic balance quality; the Kuen-Tai Tsai simultaneously utilizes an influence coefficient method and a genetic algorithm to obtain each balanced counterweight and an angle plane, so that the balance counterweights can be simultaneously placed on a plurality of balance planes, and the vibration of the bearing is reduced; spanish scholars j.g.mendoza Larios et al propose an on-line identifier method based on algebraic recognition technology, develop a multi-degree-of-freedom rotation system based on finite elements, and make two active balance disks capable of simultaneously balancing up to four vibration modes.

Disclosure of Invention

In order to solve the defects in the prior art and the problems of potential safety hazards caused by the defects, the invention provides a mass compensation optimization method for a mechanical dynamic balancing device of a high-speed spindle. The dynamic balance control device is characterized in that the dynamic balance efficiency can be effectively improved, the dynamic balance is reduced, the vibration amplitude is greatly reduced, a necessary theoretical basis is provided for improving the operation precision of a high-speed spindle system, and the problems that the machining precision of a spindle is reduced and the balance efficiency is low in the dynamic balance control process due to unbalanced vibration generated in the operation process of the high-speed spindle are solved.

In order to achieve the technical purpose, the technical scheme of the invention is as follows:

a mass compensation optimization method for a high-speed spindle mechanical dynamic balance device comprises the following steps:

step 1: running the main shaft at the expected rotating speed for experiment to obtain experiment data parameters, wherein the experiment data parameters comprise the initial phase theta 'of the balancing weight A in the mechanical balance head'_AInitial phase θ 'of weight B in mechanical balance head'_BCentrifugal force F of counterweight A at desired speed₁Centrifugal force F of weight B at desired speed₂；

Step 2: establishing mathematical modeling for the moving angle of two balancing weights in a mechanical balancing head in the high-speed spindle mechanical dynamic balancing device under polar coordinates;

and step 3: taking the established mathematical model of the movement angle of the counterweight blocks as a fitness function of a genetic algorithm, optimizing the movement strategies of the two counterweight blocks to obtain the movement angle value of the optimized counterweight block A under a polar coordinate

And the moving angle value of the balancing weight B under the polar coordinate

And 4, step 4: moving the balancing weight A by the angle value under the polar coordinateMoving the counterweight block B by the angle value under polar coordinates

To eliminate the initial unbalance of the main shaft.

The mathematical model established in the step 2 is expressed as follows:

in the formula (I), the compound is shown in the specification,

represents the moving angle value of the balancing weight A in the mechanical balancing head under the polar coordinate,

represents a value of a movement angle, θ ', of weight B in a mechanical balance head in polar coordinates'_ADenotes the initial phase, θ ', of weight A in the mechanical balance head'_BRepresenting the initial phase, F, of the counterweight B in the mechanical balance head₁Representing the centrifugal force of the counterweight A at the desired speed, F₂Representing the centrifugal force of the counterweight B at the desired rotational speed, η being the phase of the inherent unbalance of the spindle, W representing the inherent unbalance of the spindle.

The step 3 is specifically expressed as follows:

3.1) random generation of N groups by computer

As an initial solution for the first iteration;

3.2) calculating the corresponding initial solution of the jth group in the mth iteration

And according to

Is selected to be eliminated, wherein j satisfies that j is 1,2,3, …, N, m satisfies that m is 1,2,3, …, H, and H are preset iteration times;

3.3) converting the j-th group of initial solutions in the m-th iteration reserved in the step 3.2) into binary systems, and obtaining the latest solution through cross variation, wherein the cross operation is that each bit in two adjacent binary series has a preset probability P₁Randomly exchanging and randomly selecting the position of the exchange, the mutation operation is that each bit in the binary number sequence has a preset probability P₂After conversion, namely after bit conversion of 0A bit that becomes 1 becomes 0 after being converted;

3.4) taking the latest solution obtained in the step 3.3) as an initial solution of the (m + 1) th iteration, making m equal to m +1, returning to the step 3.2) for iterative calculation, and taking a result after H iterations as a final solution;

3.5) converting the final solution obtained in the step 3.4) into decimal output which is used as the moving angle value of the two optimized balancing weights under the polar coordinate

The step 3.2) is specifically expressed as follows:

3.2.1) calculate the probability p that the jth initial solution can be retained using equation (2)_j,m：

In the formula (I), the compound is shown in the specification,

representing the corresponding of the ith set of initial solutions at the mth iteration

Wherein i satisfies i ═ 1,2,3, …, N;

3.2.2) calculating each p by using the formula (3)_j,mCumulative probability of (q)_j,m：

In the formula (p)_j,m)_lRepresenting the probability p that the ith calculation is retained in the mth iteration_j,mM represents the retained probability p calculated from the N initial solutions at the mth iteration_j,mThe total number of times;

3.2.3) in [0,1]Generating a random number r within the interval, if r<q_j,mAnd if not, eliminating the jth initial solution.

The invention has the beneficial effects that:

compared with the prior art, the high-speed spindle mechanical dynamic balance mass compensation optimization method provided by the invention is beneficial to promoting the efficiency of the balance device when the mass block moves and reducing the balance time of the spindle, is also beneficial to improving the mechanical spindle balance efficiency and improving the balance precision, has great significance in reducing equipment noise, reducing loss, prolonging the service life and ensuring safe production, provides a foundation and basis for an online dynamic balance regulation and control strategy of the high-speed spindle, and has a certain engineering application value.

Drawings

Fig. 1 is a flowchart of a method for optimizing mass compensation of a high-speed spindle mechanical dynamic balancing device.

Fig. 2 is a diagram of a mechanical model of a dual-counterweight balance.

Fig. 3 is a schematic diagram of a mechanical dynamic balancing device test platform.

FIG. 4 is a flow chart illustrating the application of genetic algorithms to solve for the optimal solution of the model.

Fig. 5 is a graph showing a comparison of the balanced amplitude before and after the optimization of the mechanical dynamic balancing apparatus.

In fig. 3, 1, motor, 2, spindle, 3, sensor, 4, mechanical balance head, 5, balance system.

Detailed Description

The technical features and advantages of the present invention will become more apparent from the following detailed description of the embodiments with reference to the accompanying drawings.

As shown in the schematic diagram of the test platform of the mechanical dynamic balancing apparatus shown in fig. 3, the motor drives the motor to drive the rear spindle to operate, the sensor on the spindle can measure the amplitude phase of the spindle, and the front panel of the balancing system reads the value; the axle center of the main shaft is provided with a double-balancing-weight balancing head, and the balancing mass block can be controlled to move through a front panel of the balancing system to balance the main shaft.

As shown in the mechanical model diagram of the balancing head with the double balancing weights in fig. 2, the small balls a and B in the diagram represent two mass blocks of the balancing head respectively, the small ball C represents the unbalance amount of the spindle, and the unbalance amount C is balanced by moving the mass blocks a and B.

As shown in fig. 1, a method for optimizing mass compensation of a mechanical dynamic balancing device of a high-speed spindle includes the following steps:

step 1: respectively carrying out a plurality of groups of tests at 6 different rotating speeds of 1000r/min, 1500r/min, 2000r/min, 2500r/min, 3000r/min and 3500r/min to verify the accuracy of the model and obtain experimental data parameters, wherein the experimental data parameters comprise an initial phase theta 'of the balancing weight A in the mechanical balance head'_A0 DEG, initial phase theta of counterweight B in mechanical balance head'_B180 DEG, mass m of weights A and B_aAnd m_bAll can be equivalent to 150g, the rotating radius r is 35mm, and the centrifugal force F of the balancing weight A₁＝m_arω²Centrifugal force F of counterweight B₂＝m_brω²；

Step 2: establishing mathematical modeling for the moving angle of two balancing weights in a mechanical balancing head in the high-speed spindle mechanical dynamic balancing device under polar coordinates;

the mathematical model is expressed as:

in the formula (I), the compound is shown in the specification,represents the moving angle value of the balancing weight A in the mechanical balancing head under the polar coordinate,

represents a value of a movement angle, θ ', of weight B in a mechanical balance head in polar coordinates'_ADenotes the initial phase, θ ', of weight A in the mechanical balance head'_BRepresenting the initial phase, F, of the counterweight B in the mechanical balance head₁Representing the centrifugal force of the counterweight A at the desired speed, F₂Representing the centrifugal force of the counterweight B at the desired rotational speed, η being the phase of the inherent unbalance of the spindle,w represents the inherent imbalance force of the spindle;

and step 3: taking the mathematical model under the movement angle of the counterweight blocks as a fitness function of a genetic algorithm, optimizing the movement strategies of the two counterweight blocks to obtain the movement angle value of the optimized counterweight block A under the polar coordinateAnd the moving angle value of the balancing weight B under the polar coordinate

The flow chart is shown in fig. 4, and is specifically expressed as:

3.1) random generation of N groups by computer

As an initial solution for the first iteration;

3.2) calculating the corresponding initial solution of the jth group in the mth iterationAnd according to

Wherein j satisfies j-1, 2,3, …, N, m satisfies m-1, 2,3, …, H, and H is 100, specifically expressed as:

3.2.1) calculate the probability p that the jth initial solution can be retained using equation (2)_j,m：

In the formula (I), the compound is shown in the specification,

representing the corresponding of the ith set of initial solutions at the mth iteration

Wherein i satisfies i ═ 1,2,3, …, N;

3.2.2) calculating each p by using the formula (3)_j,mCumulative probability of (q)_j,m：

In the formula (p)_j,m)_lRepresenting the probability p that the ith calculation is retained in the mth iteration_j,mM represents the retained probability p calculated from the N initial solutions at the mth iteration_j,mThe total number of times;

3.2.3) in [0,1]Generating a random number r within the interval, if r<q_j,mIf not, eliminating the jth initial solution;

3.3) converting the j-th group of initial solutions retained in the step 3.2) during the mth iteration into binary systems, and obtaining the latest solution through cross variation, wherein the cross operation is that each bit in two adjacent binary series is randomly exchanged with the probability of 0.6, and the exchange position is randomly selected, and the variation operation is that each bit in the binary series is converted with the probability of 0.01, namely that the bit of 0 is converted into 1, and the bit of 1 is converted into 0;

3.4) taking the latest solution obtained in the step 3.3) as an initial solution of the (m + 1) th iteration, returning m to m +1 to the step 3.2) for iterative calculation, and taking a result after H iterations as a final solution;

3.5) converting the final solution obtained in the step 3.4) into decimal output which is used as the moving angle value of the two optimized balancing weights under the polar coordinate

And 4, step 4: moving the balancing weight A by the angle value under the polar coordinate

Moving the counterweight block B by the angle value under polar coordinates

To eliminate the initial unbalance of the main shaft.

And (3) analyzing an experimental result: comparing the amplitude before and after the optimization balance as shown in fig. 5, the optimal phase of the counterweight block required by the balance spindle is finally obtained, as shown in table 1:

TABLE 1 phase of rear counterweight optimized by mechanical dynamic balancing device

The balance time before and after optimization is compared to prove that the method has mechanical main shaft balance efficiency, the balance time is reduced by 31.72% on average and is reduced by 43.86% at most, as shown in table 2:

TABLE 2 comparison of equilibration times