A method and equipment for positioning inner hole of valve body

Abstract

The present application relates to the technical field of internal hole positioning processing, and specifically to a method and equipment for internal hole positioning processing for valve bodies. The method comprises: determining the path jitter characteristics of each moment in the current cutting process based on the difference between the previous acquisition moment of each moment in the current cutting process and any acquisition moment in the previous cutting process, and combining the cutting jitter characteristics of all acquisition moments in the previous cutting process; determining the path difference weights of each moment in the current cutting process, and correcting the feed speed at each moment in the valve body internal hole positioning processing process in combination with the feed speed and path jitter characteristics. The present application improves the quality of the final product of the valve body internal hole positioning processing process by real-time monitoring of the cutting vibration during the cutting process and timely adjusting the feed speed.

Description

Technical Field

[0001] The present application relates to the technical field of inner hole positioning processing, and in particular to an inner hole positioning processing method and processing equipment for a valve body. Background Art

[0002] The valve body is the core component of various valves, controlling the flow of fluids. The accuracy of the valve body's inner bore directly affects the valve's sealing performance and control flexibility. Milling is typically used during valve body machining. Milling uses a cutting tool to remove material and create a desired inner cavity within the valve body, completing the valve body process.

[0003] During the milling process, the cutter and the raw material are constantly cutting and colliding, causing the cutter to vibrate continuously. The vibration of the cutter will cause uneven cutting of the raw material, resulting in a rough surface of the inner hole, which affects the quality of the valve body. To eliminate the rough surface of the inner hole caused by the vibration of the cutter, the traditional method is to detect the vibration of the cutter and adjust the feed rate of the cutter to reduce the jitter of the cutter and improve the quality of the inner hole. However, the inner hole of the valve body usually has a complex geometry and high precision requirements. If the cutter vibration data is detected in real time, it will not be able to quickly adapt to the complex and changeable shape of the inner hole in the valve body, resulting in a rougher inner hole surface in the more complex areas of the valve body, which reduces the quality of the final product during the valve body hole positioning process. Summary of the Invention

[0004] In order to solve the above technical problems, the purpose of this application is to provide a method and equipment for positioning the inner hole of a valve body. The technical solutions adopted are as follows:

[0005] In a first aspect, an embodiment of the present application provides a method for positioning and machining an inner hole of a valve body, the method comprising the following steps:

[0006] During each cutting process of the valve body bore, the pressure data, the position coordinates of the cutting tool and the feed speed of all sampling moments within a preset time period before each moment are obtained;

[0007] Based on the pressure data of all acquisition moments before each moment, all decomposition vectors at each moment are obtained. A neighborhood is divided with any acquisition moment in each decomposition vector as the center. Based on the average distribution of all elements in the neighborhood, the jitter energy of each decomposition vector at any acquisition moment is determined. Based on the distribution of the jitter energy of all decomposition vectors at any acquisition moment, the cutting jitter characteristics at any acquisition moment are determined.

[0008] Based on the position coordinates of any acquisition moment and the previous acquisition moment, the cutting direction at any acquisition moment is determined, and the cutting jitter characteristics, position coordinates and cutting direction at any acquisition moment are combined into a path feature vector at any acquisition moment;

[0009] Based on the difference in path feature vectors between the previous acquisition moment of each moment in the current cutting process and any acquisition moment in the previous cutting process, the path feature weight of each moment in the current cutting process relative to any acquisition moment in the previous cutting process is determined. In combination with the cutting jitter features of all acquisition moments in the previous cutting process, the path jitter features of each moment in the current cutting process are determined.

[0010] Before each moment in the current cutting process, the path difference weight of each moment in the current cutting process is determined based on the difference in path feature vectors between the acquisition moments adjacent to and next adjacent to the moment;

[0011] Based on the preset feed speed and path difference weight at each moment in the cutting process, as well as the path jitter characteristics at each moment and the previous acquisition moment, the feed speed at each moment in the valve body inner hole positioning processing is corrected.

[0012] Preferably, the process of obtaining all decomposition vectors at each moment is:

[0013] The pressure data of all acquisition moments before each moment are used as the input of the wavelet decomposition algorithm, and all decomposition vectors of each moment are output.

[0014] Preferably, the method for determining the jitter energy of each decomposition vector at any acquisition moment is:

[0015] In each decomposition vector, the mean value of all elements in the neighborhood at any acquisition time is taken as the jitter energy of each decomposition vector at any acquisition time.

[0016] Preferably, the expression of the cutting jitter feature at any acquisition moment is: Where, represents the cutting jitter characteristics at acquisition time i; It represents the skewness of the jitter energy of all decomposed vectors at the acquisition time i; Indicates a preset constant greater than 0.

[0017] Preferably, the method for determining the cutting direction at a moment is:

[0018] The position coordinates of the previous acquisition moment of any acquisition moment are taken as the starting point of the cutting motion vector, and the position coordinates of any acquisition moment are taken as the end point of the cutting motion vector to obtain the cutting motion vector of any acquisition moment. The cutting direction of any acquisition moment is the unit vector of the cutting motion vector of any acquisition moment.

[0019] Preferably, the path feature weight at each moment in the process relative to any acquisition moment in the previous cutting process is the normalized value of the inverse of the difference between the path feature vectors of the previous acquisition moment of each moment in the current cutting process and any acquisition moment in the previous cutting process.

[0020] Preferably, the method for determining the path jitter characteristics at each moment in the current cutting process is:

[0021] Calculate the product of the path feature weight at each moment in the current cutting process relative to any acquisition moment in the previous cutting process and the cutting jitter feature at the corresponding acquisition moment in the previous cutting process, and take the cumulative sum of the products at each moment in the current cutting process relative to all acquisition moments in the previous cutting process as the path jitter feature at each moment in the current cutting process.

[0022] Preferably, the expression of the path difference weight at each moment in the current cutting process is: Where, represents the path difference weight at time k in this cutting process; It represents the difference in path feature vectors between the collection moments adjacent to and next to the time k before the time k in this cutting process.

[0023] Preferably, the correction of the feed speed at each moment during the positioning process of the valve body inner hole includes:

[0024] Corrected feed rate at time k during this cutting process The expression is: Where, Indicates the preset feed rate at time k in this cutting process; It represents the ratio of the path jitter feature at time k in the current cutting process to the path jitter feature at the previous acquisition time k.

[0025] In the second aspect, an embodiment of the present application also provides an internal hole positioning processing device for a valve body, comprising a memory, a processor, and a computer program stored in the memory and running on the processor. When the processor executes the computer program, it implements the steps of any one of the above-mentioned methods for internal hole positioning processing for a valve body.

[0026] This application has at least the following beneficial effects:

[0027] This application determines the cutting jitter characteristics at any collection moment by analyzing the vibration conditions of the cutting tool at different collection moments before each moment in the historical cutting process. Its beneficial effect is that it integrates the vibration data of the historical cutting process and dynamically adjusts the cutting conditions in the current cutting process to reduce vibration, thereby improving the quality of the valve body inner hole processing during the positioning processing of the valve body inner hole; This application determines the path feature weight by analyzing the differences in cutting vibration characteristics, cutting tool position coordinates and cutting direction at each moment in the current cutting process and all collection moments in the historical cutting process. Its beneficial effect is that by analyzing the differences in cutting paths at the current moment and the historical moment, it determines the reference value of the historical path characteristics to the current cutting state, thereby optimizing the cutting parameters and improving the quality of the valve body inner hole processing. and efficiency; the present application constructs the path jitter characteristics of each moment in this cutting process by comprehensively considering the path feature weights and cutting jitter characteristics, which has the beneficial effect of reflecting the vibration characteristics of the cutting tool under different postures, which can more accurately control the cutting process and improve the processing quality; the present application determines the path difference weights of each moment in this cutting process by analyzing the degree of difference in the cutting tool postures between adjacent moments, which has the beneficial effect of timely adjusting the cutting parameters and improving the processing stability; further, the present application corrects the speed at the current moment by comprehensively considering the path jitter characteristics, path difference weights and preset feed speeds at each moment in this processing process, and adjusts the feed speed in time by real-time monitoring of the cutting vibration during the cutting process, thereby improving the quality of the final product of the valve body inner hole positioning processing process. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions and advantages of the embodiments of the present application or the prior art, the following is a brief introduction to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0029] Figure 1 A flowchart of a method for positioning an inner hole of a valve body according to an embodiment of the present application;

[0030] Figure 2 A schematic diagram of a cutting jitter feature acquisition process provided in one embodiment of the present application;

[0031] Figure 3 A flow chart of a process for obtaining path jitter characteristics provided by one embodiment of the present application;

[0032] Figure 4 A schematic diagram of a corrected feed rate extraction process provided in one embodiment of the present application. DETAILED DESCRIPTION

[0033] To further illustrate the technical means and effectiveness of this application's achievement of its intended purpose, the following, in conjunction with the accompanying drawings and preferred embodiments, details the specific implementation, structure, features, and effectiveness of a valve body internal hole positioning machining method and apparatus proposed in this application. In the following description, references to "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. Furthermore, specific features, structures, or characteristics of one or more embodiments may be combined in any suitable manner.

[0034] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

[0035] The following describes in detail a specific solution of a valve body inner hole positioning processing method and processing equipment provided by the present application in conjunction with the accompanying drawings.

[0036] See also Figure 1 , which shows a flowchart of a method for positioning an inner hole of a valve body provided by an embodiment of the present application, the method comprising the following steps:

[0037] Step S1: During each cutting process of the inner hole of the valve body, pressure data, position coordinates of the cutting tool, and feed speed of all acquisition moments within a preset time period before each moment are acquired.

[0038] In the control model of a CNC machine tool, the cutter is typically given a fixed control path to complete the cutting process. During the cutting control process, the cutter's feed rate, or the amount of movement, must be controlled to ensure a smooth cutting surface and avoid affecting the quality of the valve body. Furthermore, during the cutting process, the measured pressure represents the radial force exerted by the material within the cutter's inner hole. Low pressure indicates the cutter is away from the inner hole surface, resulting in low cutting force; high pressure indicates the cutter is close to the inner hole surface, resulting in high cutting force. Changes in pressure can also represent the vibration of the cutter during milling. Minimizing vibration ensures a smoother inner hole and improves valve body quality.

[0039] Therefore, various data during the cutting process are acquired through the CNC machine control system and pressure sensors. Specifically, during each cutting process, pressure data, the position coordinates of the cutting tool, and the feed speed are acquired at each moment and at all previous acquisition times within a preset time interval t. The data acquisition frequency is set to f. The position coordinates are in the form of a two-tuple, with the two elements representing the depth and height of the cutting tool within the valve body during the cutting process, respectively.

[0040] It should be noted that the values ​​of the preset time length t and the data sampling frequency f are both manually set. In this embodiment, the value of the preset time length t is 1s, and the value of the data sampling frequency f is 100KHz. The implementer can also set them according to the specific situation. This embodiment does not impose any special restrictions.

[0041] Step S2: Based on the pressure data of all acquisition moments before each moment, all decomposition vectors at each moment are obtained, and a window is divided with any acquisition moment in each decomposition vector as the center. Based on the average distribution of all elements in the window, the jitter energy of each decomposition vector at any acquisition moment is determined, and based on the distribution of the jitter energy of all decomposition vectors at any acquisition moment, the cutting jitter characteristics at any acquisition moment are determined.

[0042] Traditional cutter control methods eliminate cutter jitter through adaptive control. These methods typically only adaptively adjust the feed rate based on the cutter's real-time jitter intensity. When jitter is excessive, the feed rate is reduced, thereby reducing jitter. Traditional cutter control methods fail to consider the impact of the cutter's control path on jitter. Consequently, in complex paths, CNC machine tools are unable to quickly respond to cutter jitter caused by path changes, resulting in a rough valve body surface.

[0043] Therefore, this embodiment controls the feed rate of the cutting blade during the cutting process by combining the path movement characteristics of the cutting blade in the previous cutting process of the current cutting process. Specifically:

[0044] (1) The pressure data of all acquisition moments before each moment are used as the input of the wavelet decomposition algorithm, and all decomposition vectors of each moment are output;

[0045] The wavelet decomposition algorithm is a well-known technology in the field of signal processing. The lengths of all decomposition vectors output by the algorithm are the same, and its specific principle will not be described in detail.

[0046] (2) Furthermore, a neighborhood is divided with any acquisition moment in each decomposition vector as the center, and the mean of all elements in the neighborhood is used as the jitter energy of each decomposition vector at any acquisition moment.

[0047] It should be noted that the value of the neighborhood radius is set manually. In this embodiment, the value of the neighborhood radius is 12. The implementer can also set it by himself according to the specific situation. This embodiment does not impose any special restrictions.

[0048] In addition, it should be understood that all decomposition vectors obtained by the wavelet decomposition algorithm have the same length as the vector composed of the original pressure data at all acquisition moments, so each decomposition vector is also composed of element values ​​at multiple acquisition moments. Therefore, it can be understood that any acquisition moment corresponds to multiple decomposition vectors.

[0049] According to the jitter energy of each decomposed vector at any acquisition moment, it can be understood that the larger the jitter energy value, the more likely the jitter of the cutter at the corresponding acquisition moment is caused by the cutter squeezing the cutting material and causing plastic deformation, and a larger feed rate should be maintained; conversely, the smaller the jitter energy value, the better the stability of the cutter at the corresponding acquisition moment.

[0050] (3) Furthermore, based on the distribution of the jitter energy of all decomposed vectors at any acquisition moment, the cutting jitter characteristics at any acquisition moment are determined, specifically:

[0051] Cutting jitter characteristics at acquisition time k The expression is: Where, It represents the skewness of the jitter energy of all decomposed vectors at the acquisition time i; Indicates a preset constant greater than 0 to prevent the calculation result from being 0. The value of is set artificially. The value of is 0.01. Under the premise of ensuring that the calculation results are not excessively affected, the implementer can set it according to the specific situation. This embodiment does not impose any special restrictions.

[0052] The calculation process of the skewness is a well-known technique, and the specific calculation steps are not repeated here.

[0053] According to the cutting jitter characteristics at any acquisition moment, it can be understood that if the skewness of the jitter energy of all decomposed vectors is greater, the cutting jitter characteristics are greater, indicating that the cutting tool jitter at the corresponding acquisition moment is more caused by the cutting tool squeezing the cutting material to cause plastic deformation, and a larger feed rate should be maintained; conversely, if the skewness of the jitter energy of all decomposed vectors is smaller, the cutting jitter characteristics are smaller, indicating that the cutting tool at the corresponding acquisition moment is more stable, and the current feed rate can be maintained.

[0054] Preferably, the schematic diagram of the cutting jitter feature acquisition process provided in this embodiment is as follows: Figure 2 shown.

[0055] In particular, if this cutting is the first time the CNC machine tool is used for processing and there is no data from the previous cutting process, the traditional cutting tool control method will still be used for this cutting.

[0056] Step S3: Based on the position coordinates of any acquisition moment and its previous acquisition moment, determine the cutting direction of any acquisition moment, and combine the cutting jitter characteristics, position coordinates and cutting direction of any acquisition moment to form a path feature vector of any acquisition moment; based on the difference in path feature vectors between the previous acquisition moment of each moment in the current cutting process and any acquisition moment in the previous cutting process, determine the path feature weight of each moment in the current cutting process relative to any acquisition moment in the previous cutting process, and combine the cutting jitter characteristics of all acquisition moments in the previous cutting process to determine the path jitter characteristics of each moment in the current cutting process.

[0057] When using a cutting tool to machine the inner hole of a valve body, different cutting tool movement paths, different contact surfaces between the cutting tool and the material, and different cutting postures will all cause the cutting tool's jitter characteristics to change during the machining process. Therefore, this embodiment comprehensively analyzes the cutting jitter characteristics under different cutting paths and establishes a relationship between the cutting tool's posture during the cutting path and the cutting jitter characteristics to more accurately control the cutting process, reduce machining errors, and improve the machining accuracy of the valve body hole. Specifically:

[0058] (1) Since the cutting posture is related to the cutting path direction and the position of the cutting tool, the position coordinates of the previous acquisition moment of any acquisition moment are used as the starting point of the cutting motion vector, and the position coordinates of any acquisition moment are used as the end point of the cutting motion vector to obtain the cutting motion vector of any acquisition moment. The unit vector of the cutting motion vector of any acquisition moment is used as the cutting direction of any acquisition moment.

[0059] (2) Furthermore, the cutting jitter characteristics, position coordinates and cutting direction at any acquisition moment are combined to form a path feature vector at any acquisition moment, wherein the path feature vector has four attribute values, namely, the cutting jitter characteristics, the depth and height of the cutting tool in the valve body during the cutting process in the position coordinates, and the cutting direction.

[0060] (3) Furthermore, the reciprocal normalized value of the difference between the previous acquisition moment of each moment in the current cutting process and any acquisition moment in the previous cutting process is taken as the path feature weight of each moment in the current cutting process relative to any acquisition moment in the previous cutting process.

[0061] It should be noted that there are many methods for measuring the differences between vectors. In this embodiment, the differences between path feature vectors are measured by calculating the Euclidean distance of the path feature vectors between each moment in the current cutting process and any acquisition moment in the previous cutting process. The implementer may also use other methods that can measure the differences between vectors, such as Mahalanobis distance and Manhattan distance. This embodiment does not impose any special restrictions on the selection of methods for measuring the differences between vectors.

[0062] The calculation process of the Euclidean distance is a well-known technology, and its specific calculation steps are not repeated here.

[0063] Furthermore, according to the path feature weights of each moment in the current cutting process relative to any acquisition moment in the previous cutting process, it can be understood that the greater the path feature weight, the smaller the difference in path feature vector between the current moment of the current cutting process and the corresponding acquisition moment in the previous cutting process, indicating that the path features between the current moment of the current cutting process and the corresponding acquisition moment in the previous cutting process are more similar, indicating that the cutting jitter feature at the corresponding acquisition moment has more reference value to the cutting jitter feature at that moment; conversely, the smaller the path feature weight, the greater the difference in path feature vector between the current moment of the current cutting process and the corresponding acquisition moment in the previous cutting process, indicating that the similarity between the path features between the current moment of the current cutting process and the corresponding acquisition moment in the previous cutting process is smaller, indicating that the cutting jitter feature at the corresponding acquisition moment has less reference value to the cutting jitter feature at that moment.

[0064] (4) Further, the product of the path feature weight at each moment in the current cutting process relative to any acquisition moment in the previous cutting process and the cutting jitter feature at the corresponding acquisition moment in the previous cutting process is calculated, and the cumulative sum of the products at each moment in the current cutting process relative to all acquisition moments in the previous cutting process is taken as the path jitter feature at each moment in the current cutting process.

[0065] According to the path jitter characteristics at each moment in this cutting process, it can be understood that the greater the path feature weight, the greater the cutting jitter characteristic, and the larger the obtained path jitter characteristic, which indicates that the cutting jitter at the current moment in this cutting process is more likely to be the cutting tool jitter caused by the cutting tool squeezing the cutting material to cause plastic deformation, and a larger feed rate should be maintained; conversely, the smaller the path feature weight, the smaller the cutting jitter characteristic, and the smaller the obtained path jitter characteristic, which indicates that the cutting tool at the current moment in this cutting process is relatively stable during the cutting process and the current feed rate can be maintained.

[0066] Preferably, the flow chart of the path jitter feature acquisition process provided in this embodiment is as follows: Figure 3 shown.

[0067] Step S4: Before each moment in this cutting process, the path difference weight of each moment in this cutting process is determined based on the difference in path feature vectors between the adjacent and next adjacent acquisition moments to this moment; based on the feed speed, path jitter characteristics and path difference weight of the previous acquisition moment in each moment in this cutting process, the feed speed at each moment in the valve body inner hole positioning processing is corrected.

[0068] CNC machine tools control the feed rate of the cutting tool by controlling the feed rate of the cutting tool during the cutting process. Therefore, this embodiment analyzes the differences in the path feature vectors between the adjacent and next adjacent acquisition moments before each moment in the current cutting process, and combines the feed rate, path jitter characteristics, and path difference weights of each moment in the current cutting process and the previous acquisition moment to correct the feed rate at each moment in the valve body inner hole positioning process. Specifically, the following corrections are made:

[0069] (1) In order to improve the stability of the valve body inner hole positioning process, the path difference weights of each moment in the current cutting process are determined based on the differences in the path feature vectors between the adjacent and next adjacent acquisition moments before each moment in the current cutting process, so as to accurately control the cutting process. Specifically,

[0070] The path difference weight at time k during this cutting process The expression is: Where, It represents the difference in path feature vectors between the collection moments adjacent to and next to the time k before the time k in this cutting process.

[0071] It should be noted that there are many methods for measuring the differences between vectors. In this embodiment, the difference between path feature vectors is measured by calculating the Euclidean distance between the path feature vectors before time k and the adjacent acquisition time and the next adjacent acquisition time of time k in the current cutting process. The implementer may also use other methods for measuring the difference between vectors, such as Manhattan distance or DTW distance. This embodiment does not impose any special restrictions on the selection of the method for measuring the difference between vectors.

[0072] According to the path difference weights at each moment in this cutting process, it can be understood that the greater the difference between the path feature vectors, the greater the path difference weight, which means that the posture difference of the cutting tool between adjacent moments is greater, and the feed speed should be corrected according to the path jitter characteristics; conversely, the smaller the difference between the path feature vectors, the smaller the path difference weight, which means that the posture difference of the cutting tool between adjacent moments is smaller, which means that the cutting tool is relatively stable during the cutting process, and the feed speed can be appropriately adjusted.

[0073] (2) Furthermore, based on the feed speed, path jitter characteristics and path difference weight of each moment in the previous acquisition time during this cutting process, the feed speed at each moment in the valve body inner hole positioning processing is corrected, specifically:

[0074] Corrected feed rate at time k during this cutting process The expression is: Where, Indicates the preset feed rate at time k in this cutting process; It represents the ratio of the path jitter feature at time k in the current cutting process to the path jitter feature at the previous acquisition time k.

[0075] It should be noted that the path jitter characteristics at any collection moment are acquired in the same manner as the path jitter characteristics at all moments.

[0076] In addition, it should be understood that the preset feed speed can be obtained through a CNC machine tool. Generally, for rough machining, the feed speed may be between 0.1 and 0.5 mm / rev; for semi-finishing, the feed speed may be between 0.05 and 0.2 mm / rev; and for finishing, the feed speed may be between 0.01 and 0.1 mm / rev. However, due to the differences in processing materials and cutting tools, the preset feed speed given by the CNC machine tool is also different at each moment. Therefore, this example no longer provides specific data, and the implementer can refer to the specific processing process for setting.

[0077] Preferably, the schematic diagram of the correction feed speed extraction process provided in this embodiment is as follows: Figure 4 shown.

[0078] At this point, this embodiment takes the complex shape of the inner hole of the valve body into consideration when considering the feed speed of the cutter during the cutting process, analyzes the cutting posture of the cutter and the relationship between the cutter's jitter and adjusts the feed speed, thereby solving the problem of cutter jitter caused by the complex shape of the inner hole of the valve body and improving the quality of the final product during the positioning processing of the inner hole of the valve body.

[0079] Based on the same inventive concept as the above method, an embodiment of the present application also provides an internal hole positioning processing device for a valve body, comprising a memory, a processor, and a computer program stored in the memory and running on the processor. When the processor executes the computer program, the steps of any one of the above-mentioned methods for internal hole positioning processing of a valve body are implemented.

[0080] It should be noted that the order in which the embodiments of the present application are presented is for illustrative purposes only and does not necessarily represent the superiority or inferiority of the embodiments. Furthermore, the foregoing descriptions of specific embodiments of this specification are provided. Furthermore, the processes depicted in the accompanying drawings do not necessarily require the specific order or sequential sequence shown to achieve the desired results. In certain embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0081] The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on the differences from other embodiments.

[0082] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the principles of the present application shall be included in the scope of protection of the present application.

Claims

1. A method for positioning the inner hole of a valve body, characterized in that: The method comprises the following steps: During each cutting process of the valve body bore, the pressure data, the position coordinates of the cutting tool and the feed speed of all sampling moments within a preset time period before each moment are obtained; Based on the pressure data of all acquisition moments before each moment, all decomposition vectors at each moment are obtained. A neighborhood is divided with any acquisition moment in each decomposition vector as the center. Based on the average distribution of all elements in the neighborhood, the jitter energy of each decomposition vector at any acquisition moment is determined. Based on the distribution of the jitter energy of all decomposition vectors at any acquisition moment, the cutting jitter characteristics at any acquisition moment are determined. Based on the position coordinates of any acquisition moment and the previous acquisition moment, the cutting direction at any acquisition moment is determined, and the cutting jitter characteristics, position coordinates and cutting direction at any acquisition moment are combined into a path feature vector at any acquisition moment; Based on the difference in path feature vectors between the previous acquisition moment of each moment in the current cutting process and any acquisition moment in the previous cutting process, the path feature weight of each moment in the current cutting process relative to any acquisition moment in the previous cutting process is determined. In combination with the cutting jitter features of all acquisition moments in the previous cutting process, the path jitter features of each moment in the current cutting process are determined. Before each moment in the current cutting process, the path difference weight of each moment in the current cutting process is determined based on the difference in path feature vectors between the acquisition moments adjacent to and next adjacent to the moment; Based on the preset feed speed and path difference weight at each moment in the cutting process, as well as the path jitter characteristics at each moment and the previous acquisition moment, the feed speed at each moment in the valve body inner hole positioning processing is corrected.

2. A method for positioning the inner hole of a valve body according to claim 1, characterized in that: The process of obtaining all decomposition vectors at each moment is as follows: The pressure data of all acquisition moments before each moment are used as the input of the wavelet decomposition algorithm, and all decomposition vectors of each moment are output.

3. The method for positioning the inner hole of a valve body according to claim 1, characterized in that: The method for determining the jitter energy of each decomposition vector at any acquisition moment is: In each decomposition vector, the mean value of all elements in the neighborhood at any acquisition time is taken as the jitter energy of each decomposition vector at any acquisition time.

4. A method for positioning the inner hole of a valve body according to claim 1, characterized in that: The expression of the cutting jitter feature at any acquisition moment is: Where, represents the cutting jitter characteristics at acquisition time i; It represents the skewness of the jitter energy of all decomposed vectors at the acquisition time i; Indicates a preset constant greater than 0.

5. The method for positioning the inner hole of a valve body according to claim 1, characterized in that: The method for determining the cutting direction at any acquisition moment is: The position coordinates of the previous acquisition moment of any acquisition moment are taken as the starting point of the cutting motion vector, and the position coordinates of any acquisition moment are taken as the end point of the cutting motion vector to obtain the cutting motion vector of any acquisition moment. The cutting direction of any acquisition moment is the unit vector of the cutting motion vector of any acquisition moment.

6. The method for positioning the inner hole of a valve body according to claim 1, characterized in that: The path feature weight of each moment in the current cutting process relative to any acquisition moment in the previous cutting process is the normalized value of the inverse of the difference between the path feature vectors of the previous acquisition moment of each moment in the current cutting process and any acquisition moment in the previous cutting process.

7. The method for positioning the inner hole of a valve body according to claim 1, characterized in that: The method for determining the path jitter characteristics at each moment in the cutting process is as follows: Calculate the product of the path feature weight at each moment in the current cutting process relative to any acquisition moment in the previous cutting process and the cutting jitter feature at the corresponding acquisition moment in the previous cutting process, and take the cumulative sum of the products at each moment in the current cutting process relative to all acquisition moments in the previous cutting process as the path jitter feature at each moment in the current cutting process.

8. The method for positioning the inner hole of a valve body according to claim 1, wherein: The expression of the path difference weight at each moment in the cutting process is: Where, represents the path difference weight at time k in this cutting process; It represents the difference in path feature vectors between the collection moments adjacent to and next to the time k before the time k in this cutting process.

9. A method for positioning the inner hole of a valve body according to claim 8, characterized in that: The correction of the feed speed at each moment during the positioning process of the valve body inner hole includes: Corrected feed rate at time k during this cutting process The expression is: Where, Indicates the preset feed rate at time k in this cutting process; It represents the ratio of the path jitter feature at time k in the current cutting process to the path jitter feature at the previous acquisition time k.

10. An inner hole positioning processing device for a valve body, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that: When the processor executes the computer program, the steps of the inner hole positioning processing method for a valve body as described in any one of claims 1 to 9 are implemented.

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