Cutter alignment control and grinding machining method suitable for air compressor shell

Abstract

The invention relates to the technical field of grinding regulation and control, in particular to a tool alignment control and grinding machining method suitable for an air compressor shell. According to the method, an initial grinding point of a grinding tool is determined for grinding according to the local distribution condition of the height and thickness of the surface of the shell; according to the grinding temperature and the grinding depth of the grinding wheel and the time sequence change degree in the grinding process, the grinding strength value of the surface of the machine shell is analyzed, and a grinding change trend index is obtained; according to the height and thickness deviation change and the vibration amplitude of the contact area in the grinding process, in combination with a grinding change trend index, parameter adjustment factors of grinding parameters are determined, and the combination of the rotating speed and the feeding speed of a grinding wheel is adjusted in real time for grinding. According to the method, the real-time parameter adjustment factors in the grinding process are determined by combining the grinding real-time strength change with the shell surface quality, correlation adjustment is carried out on the grinding parameters, and the surface adaptability and the grinding effect in the grinding process are improved.

Description

Technical Field

[0001] The invention relates to the technical field of grinding control, and in particular to a tool alignment control and grinding processing method suitable for an air compressor casing. Background Art

[0002] The grinding of air compressor casing is an important part of the manufacturing process. It is mainly used to finish the surface of the workpiece, improve the surface quality, ensure dimensional accuracy and surface finish. The grinding method is mainly used to further process the casing after forging, casting or rough processing to meet the performance requirements of the air compressor. Therefore, real-time monitoring and optimization of grinding parameters can further improve the stability and efficiency of the process, ensure the stability of processing quality and long-term operation of the equipment.

[0003] At present, when the grinding parameters of the air compressor casing are adjusted in real time during the grinding process, the parameters are generally adjusted based on data such as the grinding strength of the grinding wheel tool. However, due to the difference in surface quality at different positions on the surface of the air compressor casing, such as roughness or scratch defects, the real-time grinding parameters cannot guarantee the smoothness of the surface grinding of the entire casing, resulting in the quality of the casing surface grinding results not meeting the requirements, affecting the efficiency of the grinding process. Summary of the invention

[0004] In order to solve the technical problem that the quality of the casing surface grinding result does not meet the requirements in the prior art and affects the grinding efficiency, the purpose of the present invention is to provide a tool alignment control and grinding method suitable for air compressor casing, and the technical scheme adopted is as follows: The present invention provides a tool alignment control and grinding method applicable to an air compressor casing, the method comprising: The height and thickness of each sampling point on the surface of the casing to be ground, as well as the temperature, grinding depth and vibration amplitude of the grinding wheel at each sampling moment during the grinding process are obtained; based on the chaotic distribution of the local height and thickness of the sampling points, the initial grinding point is determined from the sampling points for grinding; Based on the time series distribution position of the sampling moment in the grinding process, the grinding intensity value at each sampling moment is obtained according to the temperature change and grinding depth at each sampling moment; based on the deviation change of the grinding intensity value between each sampling moment and the previous sampling moment, the grinding change trend index at each sampling moment is obtained; In the area corresponding to the grinding wheel contact point at the sampling moment, the regional quality index at the sampling moment is obtained according to the deviation degree of height and thickness between the sampling points and the vibration amplitude; the parameter adjustment factor at the current moment is obtained according to the deviation of the regional quality index between the current moment and the previous sampling moment and the grinding change trend index; The grinding wheel speed and feed speed at the previous sampling moment are adjusted according to the parameter adjustment factor at the current moment to obtain the grinding wheel speed and feed speed at the current moment; and grinding is performed using the grinding wheel speed and feed speed at the current moment.

[0005] Furthermore, the method for obtaining the initial grinding point includes: In the preset neighborhood of each sampling point, the variance of the height and the variance of the thickness of all sampling points are added to obtain the local roughness of each sampling point; Calculate the difference in local roughness between each sampling point and each other sampling point within a preset neighborhood to obtain the roughness difference between each sampling point and each other sampling point; sum the roughness differences between each sampling point and all other sampling points within the preset neighborhood to obtain the local difference of each sampling point; The product of the local roughness and the local difference of each sampling point is negatively correlated and mapped to obtain the initial selectivity of each sampling point; the sampling point with the highest initial selectivity is used as the initial grinding point.

[0006] Furthermore, the method for obtaining the grinding intensity value includes: Obtain the initial moment when the grinding process starts; negatively correlate the time difference between each sampling moment and the initial moment to obtain the grinding duration at each sampling moment; The difference between the temperature at each sampling moment and the temperature at the previous sampling moment is taken as the cumulative index at each sampling moment; the product of the grinding duration at each sampling moment and the cumulative index is taken as the cumulative state index at each sampling moment; The grinding intensity value at each sampling moment is obtained by multiplying the cumulative state index at each sampling moment by the grinding depth.

[0007] Furthermore, the method for obtaining the grinding change trend index includes: The difference between the grinding intensity value at each sampling moment and the previous sampling moment in the time series is taken as the intensity change value at each sampling moment; According to the degree of deviation between the grinding intensity value at each sampling moment and each previous sampling moment, the historical intensity deviation value at each sampling moment is obtained; The sum of the intensity change value at each sampling moment and the historical intensity deviation value is taken as the grinding change trend indicator at each sampling moment.

[0008] Furthermore, the method for obtaining the historical intensity deviation value includes: For any sampling moment, all sampling moments in the grinding process before the sampling moment are taken as the historical sampling moments of the sampling moment; Calculate the difference between the grinding intensity value at the sampling moment and each historical sampling moment as the intensity deviation value at each historical sampling moment; take the ratio of the intensity deviation value at each historical sampling moment to the total number of historical sampling moments as the change trend value at each historical sampling moment; The sum of the change trend values ​​of all historical sampling moments at the sampling moment is taken as the historical intensity deviation value of the sampling moment.

[0009] Furthermore, the method for obtaining the regional quality index includes: In the area corresponding to the sampling time, the height deviation index at the sampling time is obtained according to the height difference between the two sampling points and the vibration amplitude; According to the deviation between the minimum thickness of all sampling points in the area and the overall thickness, the thickness deviation index at the sampling moment is obtained; The regional quality index at the sampling moment is obtained by combining the height deviation index and the thickness deviation index at the sampling moment.

[0010] Furthermore, the method for obtaining the parameter adjustment factor includes: The ratio of the regional quality index between each sampling moment and the previous sampling moment is used as the quality change index at each sampling moment; The product of the quality change index and the grinding change trend index at each sampling moment is normalized to obtain the parameter adjustment factor at each sampling moment.

[0011] Further, the grinding wheel speed and feed speed at the previous sampling moment are adjusted according to the parameter adjustment factor at the current moment to obtain the grinding wheel speed and feed speed at the current moment, including: When the parameter adjustment factor is a positive number, the product of the grinding wheel speed at the previous sampling moment and the parameter adjustment factor is used as the grinding wheel adjustment amount of the grinding wheel speed, and the difference between the grinding wheel speed at the previous sampling moment and the grinding wheel adjustment amount is used as the grinding wheel speed at the current moment; the product of the feed speed at the previous sampling moment and the parameter adjustment factor is used as the feed adjustment amount of the feed speed, and the sum of the feed speed at the previous sampling moment and the feed adjustment amount is used as the feed speed at the current moment; When the parameter adjustment factor is a negative number, the product of the grinding wheel speed at the previous sampling moment and the absolute value of the parameter adjustment factor is used as the grinding wheel adjustment amount of the grinding wheel speed, and the sum of the grinding wheel speed at the previous sampling moment and the grinding wheel adjustment amount is used as the grinding wheel speed at the current moment; the product of the feed speed at the previous sampling moment and the absolute value of the parameter adjustment factor is used as the feed adjustment amount of the feed speed, and the difference between the feed speed at the previous sampling moment and the feed adjustment amount is used as the feed speed at the current moment; When the parameter adjustment factor is zero, the grinding wheel speed and feed speed at the previous sampling moment are used as the grinding wheel speed and feed speed at the current moment.

[0012] Furthermore, the method for obtaining the height deviation index includes: For any sampling moment, every two different sampling points within the area of ​​the sampling moment are regarded as a difference binary group; the difference in height between the sampling points in each difference binary group is calculated as the height deviation value of each difference binary group; The product of the sum of the height deviation values ​​of all difference binary groups and the vibration amplitude is used as the height deviation index at the sampling moment.

[0013] Furthermore, the method for obtaining the thickness deviation index includes: For any sampling moment, the average thickness of all sampling points within the region at the sampling moment is taken as the average regional thickness at the sampling moment; The difference between the minimum thickness in the area at the sampling moment and the average thickness of the area is used as the thickness deviation index at the sampling moment.

[0014] The present invention has the following beneficial effects: The present invention considers the initial local mass distribution of the housing surface and determines the initial grinding point of the grinding tool, thereby improving the grinding efficiency of the subsequent grinding process. The adjustment trend of the grinding intensity of the housing surface is analyzed by the time series changes of the temperature and grinding depth during grinding of the grinding wheel. The grinding state change required by the housing surface during the grinding process is reflected by real-time analysis of the change of grinding intensity. Then, combined with the rough quality of the housing surface during the grinding process, the roughness and concave-convexity of the housing surface is reflected from the height and thickness deviation and vibration amplitude in the contact area. As the quality changes during the grinding wheel grinding feed analysis, the parameter adjustment factor of the grinding parameter is comprehensively determined to adjust the real-time correlation of the grinding process, adjust the grinding force in real time, and grind by adjusting the grinding wheel rotation speed and feed speed. The present invention determines the real-time parameter adjustment factor of the grinding process by combining the real-time intensity change of the grinding with the housing surface quality, adjusts the correlation of the grinding parameters, and improves the surface adaptability and grinding effect of the grinding process. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions and advantages in the embodiments of the present invention or the prior art, the drawings required for use in the embodiments or the prior art descriptions are 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 work.

[0016] Figure 1A flow chart of a tool alignment control and grinding method for an air compressor casing provided by one embodiment of the present invention; Figure 2 A schematic diagram of a grinding process scenario provided by an embodiment of the present invention; Figure 3 A flow chart of a method for obtaining a regional quality indicator provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0017] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the following is a detailed description of the tool alignment control and grinding processing method for an air compressor casing proposed by the present invention, its specific implementation method, structure, features and effects, in combination with the accompanying drawings and preferred embodiments. In the following description, different "one embodiment" or "another embodiment" does not necessarily refer to the same embodiment. In addition, specific features, structures or characteristics in one or more embodiments may be combined in any suitable form.

[0018] 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 invention belongs.

[0019] The following is a detailed description of a specific solution of a tool alignment control and grinding method applicable to an air compressor casing provided by the present invention in conjunction with the accompanying drawings.

[0020] See also Figure 1 , which shows a flow chart of a tool alignment control and grinding method applicable to an air compressor casing provided by an embodiment of the present invention, the method comprising the following steps: S1: Obtain the height and thickness of each sampling point on the surface of the casing to be ground, as well as the temperature, grinding depth and vibration amplitude of the grinding wheel at each sampling moment during the grinding process; based on the chaotic distribution of the local height and thickness of the sampling points, determine the initial grinding point from the sampling points for grinding.

[0021] The grinding of air compressor housing is generally done by combining centerless grinding and internal grinding on grinding machines to make the outer surface of the housing smooth and clean, as well as the size accuracy and roundness of the internal holes. Grinding machines usually use various grinding wheels to perform contact grinding on the housing surface. During the grinding process, the grinding wheel speed and the moving speed of the housing on the grinding machine relative to the grinding wheel, i.e. the feed speed, will directly affect the grinding efficiency, accuracy and workpiece surface quality. Please refer to Figure 2 , which shows a schematic diagram of a grinding processing scenario provided by an embodiment of the present invention.

[0022] Before grinding begins, the surface data of the air compressor casing is first acquired. In the embodiment of the present invention, a laser scanner is integrated on the casing surface, and the surface of the casing is scanned by a laser beam to record the surface height and thickness data at each sampling point. The height refers to the vertical distance of each point on the casing surface relative to the reference plane, and characterizes the microscopic morphological characteristics of the surface. Such as bumps, scratches, roughness, etc. Non-contact measurement is performed by a laser scanner integrated on the non-contact surface of the grinding wheel. Thickness refers to the actual physical thickness of the casing material at a certain position, and the geometric dimensions from the surface to the bottom layer characterize the processing allowance of the local structure or the uniformity of material distribution. The optical reflection distance from the surface to the bottom layer is synchronously measured by a laser scanner, or dynamically calibrated in combination with the casing pre-processing data (such as a CAD model).

[0023] At the same time, the data generated by grinding is analyzed to reflect the grinding status of the grinding process. The real-time grinding wheel temperature, grinding depth and vibration amplitude data during the grinding process can be obtained through the controller and temperature sensor of the grinding machine. The data generated by grinding will be generated as long as the grinding process is carried out.

[0024] It should be noted that the specific sampling point distribution and sampling frequency settings can be adjusted by the implementer according to the specific implementation situation, such as the sampling points are distributed in a matrix with a spacing of 1 cm and the sampling frequency is once every 0.5 seconds. The specific values ​​are not limited here. The real-time grinding output data can be analyzed later and the grinding parameters can be adaptively adjusted in combination with the quality of the casing surface to improve the grinding quality and efficiency.

[0025] Since the grinding tool will accumulate friction during the grinding process, a relatively smooth position on the casing surface can be selected for the initial grinding alignment to improve the utilization of grinding force in the later stage of continuous grinding. Therefore, the possible local roughness of the sampling point is analyzed by the degree of disorder of height and thickness at the sampling point position, and grinding is performed when the roughness is lower.

[0026] Preferably, in an embodiment of the present invention, the method for obtaining the initial grinding point includes: First, within the preset neighborhood of each sampling point, the variance of the height and the variance of the thickness of all sampling points are added to obtain the local roughness of each sampling point. The variance of the height and the variance of the thickness within the range reflect the degree of chaos in the data distribution of height and thickness. The larger the variance, the more chaotic the data distribution. Taking the variance of height and thickness into consideration, the larger the sum of the variances, the rougher the surface condition at the sampling point may be.

[0027] Since the grinding process is a continuous grinding process, the more stable the overall distribution level of the local sampling points is, the more reliable the local state analysis of the sampling points is, and the higher the possibility that the local state is flat. Therefore, the difference in local roughness between each sampling point and each other sampling point in the preset neighborhood is calculated to obtain the roughness difference between each sampling point and each other sampling point, reflecting the consistency of the surface condition at the local sampling point position. The larger the roughness difference, the more inconsistent the surface state.

[0028] The sum of the roughness differences between each sampling point and all other sampling points in the preset neighborhood is further calculated to obtain the local difference of each sampling point. Combining all the differences, the smaller the overall difference is, the more stable and consistent the local situation of the sampling point position is, and the better the sampling point is as the starting point of grinding.

[0029] Finally, the product of the local roughness and local difference of each sampling point is negatively correlated to obtain the initial selectivity of each sampling point. Combined with the consistency of the local difference of the sampling point and the roughness of the analysis, the degree to which the sampling point can be selected is obtained. When the local roughness is smaller, it means that the degree of smoothness at the sampling point is higher. When the local difference is smaller, it means that the local surface of the sampling point is more consistent, and the sampling point is more likely to be selected as the initial grinding point. Therefore, the sampling point with the highest initial selectivity is used as the initial grinding point.

[0030] In a specific embodiment of the present invention, the preset neighborhood range is set to a range with a sampling point as the center and a side length of 7, and the specific value can be adjusted by the implementer, and is not limited here. It should be noted that negative correlation mapping is a technical means well known to those skilled in the art, such as using an inverse proportional value or a negative exponential power form, etc., which will not be repeated or limited here.

[0031] S2: Based on the temporal distribution position of the sampling moment in the grinding process, the grinding intensity value at each sampling moment is obtained according to the temperature change and grinding depth at each sampling moment; according to the deviation change of the grinding intensity value between each sampling moment and the previous sampling moment, the grinding change trend index at each sampling moment is obtained.

[0032] Based on the initial grinding point position, the grinding tool is aligned and then the grinding process is performed. Since the grinding process requires contact and friction between the grinding wheel and the shell surface, the corresponding grinding intensity is determined by the real-time data generated during the grinding process. The grinding intensity represents the degree to which the grinding wheel acts on the shell, reflects the real-time grinding state, and performs feedback adjustment of relevant parameters to optimize the grinding process.

[0033] Since the grinding wheel performs friction cutting on the casing with a certain intensity, the greater the grinding depth, the greater the grinding intensity. At the same time, the heat generated on the surface of the grinding wheel during the friction process, the greater the heat, the greater the grinding intensity at this time, but in the actual grinding process, the heat of the grinding wheel will have a cumulative effect, resulting in a decrease in the heat dissipation rate as the grinding proceeds, and the grinding wheel temperature continues to increase, and the real-time heat situation reflects the real-time friction intensity inaccurately. Therefore, considering the friction accumulation of the abrasive tool during the grinding process, combined with the time series distribution of the sampling time, the intensity is reflected by the temperature change and the grinding depth to determine the grinding intensity value.

[0034] Preferably, in an embodiment of the present invention, the method for obtaining the grinding intensity value includes: First, the initial moment of the grinding process is obtained, and the time difference between each sampling moment and the initial moment is negatively correlated to obtain the grinding duration at each sampling moment. The time difference between the sampling moment and the initial moment reflects the duration of the grinding.

[0035] The difference between the temperature at each sampling moment and the previous sampling moment is further used as the cumulative index at each sampling moment. The temperature change of the grinding wheel is used to characterize the real-time heat accumulation to measure the friction force of the grinding wheel. The product of the grinding duration at each sampling moment and the cumulative index is used as the cumulative state index at each sampling moment. Since the cumulative effect of temperature in the actual grinding process will cause the grinding wheel temperature and grinding depth to continue to increase as the grinding progresses, it will interfere with the actual friction force. Therefore, the grinding duration is used as the weight for adjustment. If the longer the grinding time, the higher the temperature accumulation, the greater the error.

[0036] Finally, the product of the cumulative state index at each sampling moment and the grinding depth is obtained to obtain the grinding intensity value at each sampling moment. Combined with the grinding depth, the deeper the grinding depth, the greater the grinding intensity, which comprehensively reflects the grinding intensity at the current moment. As an example, the expression of the grinding intensity value is: ; In the formula, It is expressed as the first The grinding intensity value at the sampling moment, Expressed as The cumulative index of the sampling time, Represents the initial moment when the grinding process begins, Expressed as The grinding depth at the sampling moment. It is represented as a preset adjustment coefficient, which is set to 0.001 in the embodiment of the present invention, and its purpose is to prevent the denominator from being zero, making the formula meaningless. Expressed as Grinding duration at each sampling moment, Expressed as The cumulative status indicator at each sampling moment.

[0037] The real-time grinding intensity of the casing during the grinding process will change as the grinding progresses. If the changing trend of the continuously adjusted grinding intensity increases, it means that the grinding force required at the grinding position is greater. Conversely, it means that the adjusted grinding intensity needs to reduce the corresponding grinding force. The grinding force is adjusted by matching the grinding wheel speed with the feed speed. The changing trend of the grinding intensity at different times can represent the degree of adjustment. Therefore, the grinding change trend index is obtained through the changing trend of the grinding intensity value between the sampling time and the previous sampling time, providing data support for subsequent adjustments.

[0038] Preferably, in an embodiment of the present invention, the method for obtaining the grinding change trend index includes: Firstly, the difference between the grinding intensity value at each sampling moment and the previous sampling moment in time series is taken as the intensity change value at each sampling moment, which represents the difference in the grinding intensity value change between the sampling moment and the previous moment, and reflects the change trend of the local grinding intensity at the current moment.

[0039] Further, according to the degree of deviation between the grinding intensity value at each sampling moment and each previous sampling moment, the historical intensity deviation value at each sampling moment is obtained, and the overall change trend of the grinding intensity in the historical stage is reflected in combination with the change of the grinding intensity at the historical moment, so as to assist in adjusting the degree of the current local change trend. In an embodiment of the present invention, the method for obtaining the historical intensity deviation value includes: For any sampling moment, all sampling moments in the grinding process before the sampling moment are taken as the historical sampling moments of the sampling moment to determine the existence of the historical moments. Only when the sampling moment is the initial moment, there is no historical sampling moment, so the historical deviation value is not calculated for adjustment at this time.

[0040] The difference between the grinding intensity value of the sampling moment and each historical sampling moment is further calculated as the intensity deviation value between each historical sampling moment, reflecting the deviation between the current moment and the historical moment. The ratio of the intensity deviation value between each historical sampling moment and the total number of historical sampling moments is used as the change trend value of each historical sampling moment, which is evenly divided by the total number of historical sampling moments, and the sum of the change trend values ​​of all historical sampling moments at the sampling moment is used as the historical intensity deviation value of the sampling moment, that is, the deviation of the grinding intensity value between the sampling moment and all historical moments is comprehensively analyzed to reflect the historical change trend.

[0041] Finally, the sum of the intensity change value and the historical intensity deviation value at each sampling moment is used as the grinding change trend index at each sampling moment. The adjustment requirements of the grinding force required for grinding are analyzed in combination with the local changes and the historical trend degree, so that the subsequent adjustment results can be used for more efficient grinding. As an example, the expression of the grinding change trend index is: ; In the formula, It is expressed as the first Grinding change trend index at each sampling moment. Expressed as The grinding intensity value at the sampling moment, Expressed as The grinding intensity value at the sampling moment before the sampling moment, that is, The grinding intensity value at the sampling moment, Expressed as The grinding intensity value at the historical sampling moment, Expressed as the total number of historical sampling moments. Expressed as The intensity change value at each sampling moment, Expressed as The intensity deviation value at the historical sampling moment, Expressed as The change trend value of the historical sampling moment, Expressed as The historical intensity deviation value at each sampling moment.

[0042] S3: In the area corresponding to the grinding wheel contact point at the sampling moment, the regional quality index at the sampling moment is obtained according to the deviation degree of height and thickness between the sampling points and the vibration amplitude; the parameter adjustment factor at the current moment is obtained according to the deviation of the regional quality index between the current moment and the previous sampling moment and the grinding change trend index.

[0043] If the grinding parameters are adjusted only according to the grinding trend index without considering the surface quality of the casing itself, and lacking the connection with the actual product, the smoothness of different positions on the casing surface will have a counter-effect on the friction of the grinding wheel, thus affecting the grinding effect. Therefore, the impact of the surface quality of the casing itself on the grinding effect should be considered. If the surface area of ​​the casing is rougher during the grinding process, a greater grinding force is required to achieve a better grinding effect. On the contrary, if a certain area is smoother, a greater grinding force is not required to achieve the purpose.

[0044] When grinding the forged air compressor casing, it is necessary to grind and smooth the surface of the casing because scratches and bumps of varying degrees will inevitably occur during the forging process. The degree of smoothness at different positions on the casing surface is different, and the required grinding force is also different. Therefore, the quality of the area that needs to be ground each time is analyzed through the surface information obtained in advance to obtain the regional quality index.

[0045] Preferably, in the embodiment of the present invention, the method for obtaining the regional quality index can be found in Figure 3 , which shows a flow chart of a method for obtaining a regional quality indicator provided by an embodiment of the present invention, the method comprising the following steps: S301: In the area corresponding to the sampling time, according to the height difference between two sampling points, combined with the vibration amplitude, a height disorder index at the sampling time is obtained.

[0046] First, the surface unevenness is measured based on the height difference in the contact grinding area. The greater the height difference, the higher the surface roughness. It should be noted that since the grinding process is contact grinding, there is a contact area range during grinding. The size of the contact area range is obtained based on the size of the grinding tool in the implementation scenario and is not limited here.

[0047] In the embodiment of the present invention, for any sampling moment, every two different sampling points within the region of the sampling moment are taken as a difference binary group, and the height differences between all sampling points are grouped and analyzed by pairwise combination. The height difference between the sampling points in each difference binary group is calculated as the height deviation value of each difference binary group, reflecting the degree of height unevenness in each grouping case.

[0048] Due to the unevenness of the surface of the casing, the force of the grinding wheel will produce different vibrations on the surface of the casing. When the roughness increases, the vibration amplitude tends to increase accordingly. Then the product of the sum of the height deviation values ​​of all difference binary groups and the vibration amplitude is taken as the height deviation index at the sampling moment. The unevenness is characterized by combining all the difference degrees. The larger the height deviation index, the more serious the unevenness of the regional surface and the higher the roughness.

[0049] S302: Obtain a thickness disorder index at the sampling moment according to the degree of deviation between the minimum thickness of all sampling points within the region and the overall thickness.

[0050] However, the surface of the housing itself is generally not a plane, and will show different concave and convex trends. When the grinding wheel is grinding the concave and convex surface, the contact area between the grinding wheel and the housing changes, so the corresponding grinding intensity needs to be increased to achieve the corresponding grinding effect and improve the surface adaptability of the grinding. Therefore, the local concave and convex degree of the surface is further measured based on the thickness difference in the contact grinding area. When the thickness deviation result is higher, it means that there is a certain concave and convex situation, the higher the degree of grinding required, the greater the grinding force that needs to be adjusted later, and the more serious the quality of the area is.

[0051] In the embodiment of the present invention, for any sampling moment, the average thickness of all sampling points within the region at the sampling moment is taken as the regional thickness average at the sampling moment, reflecting the relative overall thickness distribution of the region. The difference between the minimum thickness within the region at the sampling moment and the regional thickness average is taken as the thickness deviation index at the sampling moment. The larger the minimum thickness deviation, the more concave-convex the surface is locally, the more difficult it is to grind the surface flat, the worse the quality is, and the higher the degree of roughness is.

[0052] S303: Combining the height disorder index and the thickness disorder index at the sampling time, obtaining the regional quality index at the sampling time.

[0053] Comprehensively analyze the height and thickness to comprehensively characterize the regional quality. In the embodiment of the present invention, the product of the height disorder index and the thickness disorder index at the sampling moment is normalized to obtain the regional quality index at the sampling moment. The greater the height disorder index and the thickness disorder index, the greater the roughness, the more serious the quality, and the greater the grinding force required. It should be noted that normalization is a technical means well known to those skilled in the art, and the choice of normalization can be linear normalization or standard normalization, etc. The specific normalization method is not limited here.

[0054] At this point, the regional quality analysis implemented in the grinding process is completed. Then, the adjustment factor of the parameter can be determined based on the grinding intensity state to reflect the situation where the grinding parameter needs to be adjusted. Preferably, in an embodiment of the present invention, the method for obtaining the parameter adjustment factor includes: According to the ratio of the regional quality index between each sampling moment and the previous sampling moment, as the quality change index at each sampling moment, the contact area range also changes during the mobile grinding process. When the quality of the regional quality index increases, it reflects the need to increase the grinding force.

[0055] Then, the product of the quality change index and the grinding change trend index at each sampling moment is normalized to obtain the parameter adjustment factor at each sampling moment. The larger the quality change index and the grinding change trend index, that is, the parameter adjustment factor, the rougher the surface quality of the casing, the higher the demand for increasing grinding intensity, and more grinding force is required.

[0056] S4: adjusting the grinding wheel speed and feed speed at the previous sampling moment according to the parameter adjustment factor at the current moment to obtain the grinding wheel speed and feed speed at the current moment; performing grinding at the grinding wheel speed and feed speed at the current moment.

[0057] The main adjustment of grinding parameters is on the grinding wheel speed and feed speed, and the grinding wheel speed and feed speed have different correlations with the grinding force. A higher grinding wheel speed will increase the speed of the grinding wheel cutting the workpiece, and the contact time between each abrasive tool and the workpiece surface will be reduced, thereby reducing the cutting force per unit time. Increasing the feed speed means that the contact area between the workpiece and the grinding wheel per unit time increases, and the grinding depth increases, which directly leads to an increase in the grinding force.

[0058] Therefore, if you want to increase the grinding force, you need a combination of low grinding wheel speed and high feed rate, and if you want to reduce the grinding force, you need a combination of high grinding wheel speed and low feed rate. Based on this feature, combined with the parameter adjustment factor, the current grinding wheel speed and feed rate are adjusted.

[0059] Preferably, in an embodiment of the present invention, the grinding wheel speed and feed speed at the previous sampling moment are adjusted according to the parameter adjustment factor at the current moment to obtain the grinding wheel speed and feed speed at the current moment, including: When the parameter adjustment factor is a positive number, it means that the trend of grinding intensity is increasing. The product of the grinding wheel speed at the previous sampling moment and the parameter adjustment factor is used as the grinding wheel adjustment amount of the grinding wheel speed. The larger the parameter adjustment factor, the greater the degree of adjustment required. The difference between the grinding wheel speed at the previous sampling moment and the grinding wheel adjustment amount is used as the grinding wheel speed at the current moment. Similarly, the product of the feed speed at the previous sampling moment and the parameter adjustment factor is used as the feed adjustment amount of the feed speed, and the sum of the feed speed at the previous sampling moment and the feed adjustment amount is used as the feed speed at the current moment. The grinding force is increased by reducing the grinding wheel speed and increasing the feed speed.

[0060] When the parameter adjustment factor is negative, it means that the trend of grinding intensity is decreasing. The product of the grinding wheel speed at the previous sampling moment and the absolute value of the parameter adjustment factor is used as the grinding wheel adjustment amount of the grinding wheel speed. The larger the absolute value of the parameter adjustment factor, the higher the adjustment intensity. The sum of the grinding wheel speed at the previous sampling moment and the grinding wheel adjustment amount is used as the grinding wheel speed at the current moment. The product of the feed speed at the previous sampling moment and the absolute value of the parameter adjustment factor is used as the feed adjustment amount of the feed speed. The difference between the feed speed at the previous sampling moment and the feed adjustment amount is used as the feed speed at the current moment. The grinding force is reduced by increasing the grinding wheel speed and reducing the feed speed.

[0061] In addition, when the parameter adjustment factor is zero, it means that no strength adjustment is required, and the grinding wheel speed and feed speed at the previous sampling moment are used as the grinding wheel speed and feed speed at the current moment. As an example, the adjustment expression of the grinding wheel speed and feed speed is: ; ; In the formula, Expressed as The grinding wheel speed at the sampling moment, Expressed as The feed speed at each sampling moment, Expressed as The grinding wheel speed at the sampling time before the sampling time, that is, The grinding wheel speed at the sampling moment, Expressed as The feed rate at the sampling time before the sampling time, that is, The feed speed at each sampling moment, Expressed as The parameter adjustment factor at each sampling moment, Expressed as an absolute value extraction function.

[0062] in, It is expressed as the grinding wheel adjustment amount when the parameter adjustment factor is a positive number. It is expressed as the feed adjustment amount when the parameter adjustment factor is a positive number. It is expressed as the grinding wheel adjustment amount when the parameter adjustment factor is negative. Expressed as the feed adjustment amount when the parameter adjustment factor is a negative number.

[0063] The grinding wheel speed and feed speed at the current moment are obtained through real-time correlation adjustment for grinding, so as to achieve the purpose of improving the quality of the ground product. The correlation adjustment is performed for the real-time grinding wheel speed and feed speed of the air compressor casing during the grinding process. The system can automatically optimize the processing parameters according to the actual situation of the workpiece to ensure the processing quality and efficiency. In the embodiment of the present invention, the parameters can also be optimized in real time based on the experience of relevant operators to further improve the stability and reliability of the grinding process.

[0064] In summary, the present invention considers the initial local mass distribution of the housing surface and determines the initial grinding point of the grinding tool, thereby improving the grinding efficiency of the subsequent grinding process. The adjustment trend of the grinding intensity of the housing surface is analyzed by the time series changes of the temperature and grinding depth during grinding of the grinding wheel. The grinding state change required by the housing surface during the grinding process is reflected by real-time analysis of the change in grinding intensity. Then, combined with the rough quality of the housing surface during the grinding process, the roughness and concave-convexity of the housing surface is reflected from the height and thickness deviations and vibration amplitude in the contact area. As the quality changes during the grinding wheel grinding feed analysis, the parameter adjustment factor of the grinding parameter is comprehensively determined to adjust the real-time correlation of the grinding process, adjust the grinding force in real time, and grind by adjusting the grinding wheel speed and feed speed. The present invention determines the real-time parameter adjustment factor of the grinding process by combining the real-time intensity change of the grinding with the housing surface quality, adjusts the correlation of the grinding parameters, and improves the surface adaptability and grinding effect of the grinding process.

[0065] It should be noted that the sequence of the above embodiments of the present invention is only for description and does not represent the advantages and disadvantages of the embodiments. The processes depicted in the accompanying drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0066] The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referenced to each other, and each embodiment focuses on the differences from other embodiments.

Claims

1. A tool alignment control and grinding method suitable for an air compressor casing, characterized in that: The method comprises: The height and thickness of each sampling point on the surface of the casing to be ground, as well as the temperature, grinding depth and vibration amplitude of the grinding wheel at each sampling moment during the grinding process are obtained; based on the chaotic distribution of the local height and thickness of the sampling points, the initial grinding point is determined from the sampling points for grinding; Based on the time series distribution position of the sampling moment in the grinding process, the grinding intensity value at each sampling moment is obtained according to the temperature change and grinding depth at each sampling moment; based on the deviation change of the grinding intensity value between each sampling moment and the previous sampling moment, the grinding change trend index at each sampling moment is obtained; In the area corresponding to the grinding wheel contact point at the sampling moment, the regional quality index at the sampling moment is obtained according to the deviation degree of height and thickness between the sampling points and the vibration amplitude; the parameter adjustment factor at the current moment is obtained according to the deviation of the regional quality index between the current moment and the previous sampling moment and the grinding change trend index; The grinding wheel rotation speed and feed speed at the previous sampling moment are adjusted according to the parameter adjustment factor at the current moment to obtain the grinding wheel rotation speed and feed speed at the current moment; and grinding is performed using the grinding wheel rotation speed and feed speed at the current moment.

2. A tool alignment control and grinding method for an air compressor casing according to claim 1, characterized in that: The method for obtaining the initial grinding point comprises: In the preset neighborhood of each sampling point, the variance of the height and the variance of the thickness of all sampling points are added to obtain the local roughness of each sampling point; Calculate the difference in local roughness between each sampling point and each other sampling point within a preset neighborhood to obtain the roughness difference between each sampling point and each other sampling point; sum the roughness differences between each sampling point and all other sampling points within the preset neighborhood to obtain the local difference of each sampling point; The product of the local roughness and the local difference of each sampling point is negatively correlated and mapped to obtain the initial selectivity of each sampling point; the sampling point with the highest initial selectivity is used as the initial grinding point.

3. A tool alignment control and grinding method for an air compressor casing according to claim 1, characterized in that: The method for obtaining the grinding intensity value comprises: Obtain the initial moment when the grinding process starts; negatively correlate the time difference between each sampling moment and the initial moment to obtain the grinding duration at each sampling moment; The difference between the temperature at each sampling moment and the temperature at the previous sampling moment is taken as the cumulative index at each sampling moment; the product of the grinding duration at each sampling moment and the cumulative index is taken as the cumulative state index at each sampling moment; The grinding intensity value at each sampling moment is obtained by multiplying the cumulative state index at each sampling moment by the grinding depth.

4. A tool alignment control and grinding method for an air compressor casing according to claim 1, characterized in that: The method for obtaining the grinding change trend index includes: The difference between the grinding intensity value at each sampling moment and the previous sampling moment in the time series is taken as the intensity change value at each sampling moment; According to the degree of deviation between the grinding intensity value at each sampling moment and each previous sampling moment, the historical intensity deviation value at each sampling moment is obtained; The sum of the intensity change value at each sampling moment and the historical intensity deviation value is taken as the grinding change trend indicator at each sampling moment.

5. A tool alignment control and grinding method for an air compressor casing according to claim 4, characterized in that: The method for obtaining the historical intensity deviation value includes: For any sampling moment, all sampling moments in the grinding process before the sampling moment are taken as the historical sampling moments of the sampling moment; Calculate the difference between the grinding intensity value at the sampling moment and each historical sampling moment as the intensity deviation value at each historical sampling moment; take the ratio of the intensity deviation value at each historical sampling moment to the total number of historical sampling moments as the change trend value at each historical sampling moment; The sum of the change trend values ​​of all historical sampling moments at the sampling moment is taken as the historical intensity deviation value of the sampling moment.

6. The tool alignment control and grinding method for an air compressor casing according to claim 1, characterized in that: The method for obtaining the regional quality index includes: In the area corresponding to the sampling time, the height deviation index at the sampling time is obtained according to the height difference between the two sampling points and the vibration amplitude; According to the deviation between the minimum thickness of all sampling points in the area and the overall thickness, the thickness deviation index at the sampling moment is obtained; The regional quality index at the sampling moment is obtained by combining the height deviation index and the thickness deviation index at the sampling moment.

7. A tool alignment control and grinding method for an air compressor casing according to claim 1, characterized in that: The method for obtaining the parameter adjustment factor includes: The ratio of the regional quality index between each sampling moment and the previous sampling moment is used as the quality change index at each sampling moment; The product of the quality change index and the grinding change trend index at each sampling moment is normalized to obtain the parameter adjustment factor at each sampling moment.

8. The tool alignment control and grinding method for an air compressor casing according to claim 1, characterized in that: The grinding wheel speed and feed speed at the previous sampling moment are adjusted according to the parameter adjustment factor at the current moment to obtain the grinding wheel speed and feed speed at the current moment, including: When the parameter adjustment factor is a positive number, the product of the grinding wheel speed at the previous sampling moment and the parameter adjustment factor is used as the grinding wheel adjustment amount of the grinding wheel speed, and the difference between the grinding wheel speed at the previous sampling moment and the grinding wheel adjustment amount is used as the grinding wheel speed at the current moment; the product of the feed speed at the previous sampling moment and the parameter adjustment factor is used as the feed adjustment amount of the feed speed, and the sum of the feed speed at the previous sampling moment and the feed adjustment amount is used as the feed speed at the current moment; When the parameter adjustment factor is a negative number, the product of the grinding wheel speed at the previous sampling moment and the absolute value of the parameter adjustment factor is used as the grinding wheel adjustment amount of the grinding wheel speed, and the sum of the grinding wheel speed at the previous sampling moment and the grinding wheel adjustment amount is used as the grinding wheel speed at the current moment; the product of the feed speed at the previous sampling moment and the absolute value of the parameter adjustment factor is used as the feed adjustment amount of the feed speed, and the difference between the feed speed at the previous sampling moment and the feed adjustment amount is used as the feed speed at the current moment; When the parameter adjustment factor is zero, the grinding wheel speed and feed speed at the previous sampling moment are used as the grinding wheel speed and feed speed at the current moment.

9. A tool alignment control and grinding method for an air compressor casing according to claim 6, characterized in that: The method for obtaining the height deviation index includes: For any sampling moment, every two different sampling points within the area of ​​the sampling moment are regarded as a difference binary group; the difference in height between the sampling points in each difference binary group is calculated as the height deviation value of each difference binary group; The product of the sum of the height deviation values ​​of all difference binary groups and the vibration amplitude is taken as the height deviation index at the sampling moment.

10. The tool alignment control and grinding method for an air compressor casing according to claim 6, characterized in that: The method for obtaining the thickness deviation index includes: For any sampling moment, the average thickness of all sampling points within the region at the sampling moment is taken as the average regional thickness at the sampling moment; The difference between the minimum thickness in the area at the sampling moment and the average thickness of the area is used as the thickness deviation index at the sampling moment.

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