Multi-shaft combined machining tool

Abstract

The invention relates to the technical field of multi-axis combined machining machine tools, in particular to a multi-axis combined machining machine tool which is provided with a rack, a moving assembly, a workpiece cradle, a stress detection unit and a process control unit, and the moving assembly comprises an X-axis moving mechanism, a Y-axis moving mechanism and a Z-axis moving mechanism; the Z-axis moving mechanism comprises a milling cutter machining unit and a grinding head machining unit, a to-be-machined workpiece is borne through the workpiece cradle, cooperative cooperation of shafts of different machining process units such as the milling cutter machining unit and the grinding head machining unit is achieved, and the machining efficiency is improved; the process control unit determines a stress unit vector and adjusts the single sliding distance of the feeding sliding table according to the change conditions of the stress unit vector in the spatial dimension and the time dimension, so that adaptive adjustment on machining parameters in a special machining time period is achieved according to the real-time analysis result of the machining process parameters. And the machining effect and the machining precision of the thin-wall workpiece are improved.

Description

Technical Field

[0001] The invention relates to the technical field of multi-axis combined machining machine tools, and in particular to a multi-axis combined machining machine tool. Background Art

[0002] The application of multi-axis compound processing machine tools in the field of mechanical processing is becoming more and more extensive. Multi-axis compound processing machine tools can realize the integration of multiple processing technologies on the same equipment, effectively improving the processing efficiency and processing accuracy. In the processing of milling and grinding, due to the complex and changeable interaction forces between the workpiece and the cutting tool and the mold, it is easy to cause the processing accuracy to be difficult to achieve the ideal state.

[0003] Thin-walled parts are used more and more widely to meet the diversified needs of modern industrial production. For the processing of thin-walled parts, due to the poor rigidity of thin-walled parts, the errors caused by cutting force and processing impact force are more obvious. Different processing technologies have different requirements for processing parameters. In actual processing, it is difficult to avoid processing damage and deformation of thin-walled parts, which affects processing efficiency and product quality. It is urgent to have machine tools with process adaptability adjustments for coordinated multi-axis to meet the needs of modern industrial production.

[0004] For example, China Patent Publication No.: CN110814758A, the invention discloses a variable steering multi-spindle drilling and milling machine tool, and its technical solution is: the control drive system controls and drives the start, stop and speed change of the main motor, the speed regulating motor, and the lifting motor according to the input instructions through the data drive line, the opening and closing of the electromagnetic brake, the inward and outward movement of the horizontal feed worktable, the left and right movement of the longitudinal feed worktable, and the up and down movement of the machine tool lifting platform, which can realize efficient milling of the workpiece and simultaneous drilling of a hole group formed by multiple holes, greatly improving the processing efficiency of milling and drilling.

[0005] The prior art still has the following problems:

[0006] The prior art does not take into account that excessive or insufficient feed rate of the grinding head during machining of thin-walled workpieces may easily cause axial movement and radial runout of the workpiece, thus affecting machining accuracy. The prior art cannot adaptively adjust machining parameters in special machining time periods based on real-time analysis of machining process parameters, thus affecting machining effect and machining accuracy of thin-walled workpieces. Summary of the invention

[0007] To this end, the present invention provides a multi-axis compound machining machine tool to overcome the problem in the prior art that the machining parameters cannot be analyzed in real time and the machining parameters in a special machining time period cannot be adaptively adjusted.

[0008] To achieve the above object, the present invention provides a multi-axis composite machining machine tool, comprising:

[0009] A frame, comprising a base and a crossbeam arranged on the base;

[0010] A moving assembly, comprising an X-axis moving mechanism, a Y-axis moving mechanism and a Z-axis moving mechanism, wherein the X-axis moving mechanism comprises a slide rail arranged at the front of the crossbeam and an X-axis slide saddle arranged on the slide rail;

[0011] The Y-axis moving mechanism comprises a slide rail arranged on the upper surface of the base and a Y-direction slide saddle arranged on the slide rail;

[0012] The Z-axis moving mechanism comprises a Z-direction first slide saddle and a Z-direction second slide saddle respectively arranged on the slide rails on the surface of the X-direction slide saddle, a milling cutter processing unit is arranged on the Z-direction first slide saddle, and a grinding head processing unit is arranged on the Z-direction second slide saddle, and the grinding head processing unit comprises a grinding head and a feed slide table driving the grinding head to slide along the radial direction of the rotation of the grinding head;

[0013] A workpiece cradle, which is used to carry the workpiece to be processed, comprises a support frame fixed on the Y-axis slide saddle and a cradle body, wherein both ends of the cradle body are connected to the support frame through a rotating shaft and a bearing so that the cradle body rotates about the axis of the rotating shaft;

[0014] Stress detection units are respectively arranged at both ends of the support frame to obtain the contact stress value between the bearing and the sleeve;

[0015] A process control unit is respectively connected to the stress detection unit and the moving component, and is used to determine the stress unit vector according to the contact stress conditions at both ends of the support frame and adjust the single sliding distance of the feed slide according to the changes of the stress unit vector in the spatial dimension and the time dimension.

[0016] Furthermore, a tool changing magazine for storing milling cutters is provided on one side of the crossbeam close to the milling cutter processing unit.

[0017] Furthermore, the grinding head processing unit further includes a grinding head revolution axis and a grinding head rotation axis, and the grinding head revolution axis drives the grinding head on the feed slide to revolve with the axis center line of the grinding head revolution axis as a reference;

[0018] The grinding head rotation shaft is arranged on the feed slide to drive the grinding head to rotate with the axis of the grinding head rotation shaft as the reference;

[0019] The circumferential radius of the revolution is determined according to the sliding distance of the grinding head driven by the feed slide along the radial direction of the grinding head's rotation.

[0020] Furthermore, a workpiece spindle for carrying the workpiece to be processed is also provided on the cradle body, so that the workpiece spindle drives the workpiece to be processed to rotate.

[0021] Further, the process control unit is used to determine the stress unit vector according to the contact stress value between the rotating shaft and the bearing;

[0022] The vector end point of the stress unit vector is the position where the maximum contact stress is located in the contact position between the rotating shaft and the bearing, and the vector starting position of the stress unit vector is the center position of the bearing.

[0023] Furthermore, the process control unit is used to determine the change of the stress unit vector in the time dimension, wherein:

[0024] The process control unit is used to obtain stress unit vectors corresponding to several moments in a preset monitoring period, and determine the maximum angle between two stress unit vectors according to the stress unit vectors corresponding to the several moments.

[0025] Furthermore, the process control unit is also used to determine whether the preset monitoring cycle is a processing feature cycle, wherein:

[0026] If the maximum angle meets the characteristic phenomenon screening condition, the process control unit determines that the preset monitoring period is a processing characteristic period;

[0027] The characteristic phenomenon screening condition is that the maximum angle between two stress unit vectors at any end of the support frame within a preset monitoring period exceeds a preset angle threshold.

[0028] Furthermore, the process control unit is also used to determine the characteristic characterization angle of the stress unit vector in the spatial dimension, wherein:

[0029] Under the condition that the preset monitoring period is determined to be a processing characteristic period, the process control unit obtains the stress unit vectors corresponding to each end of the support frame at several moments within the preset monitoring period, and determines the angle between the two stress unit vectors at the two ends of the support frame at the same moment as the characteristic characterization angle.

[0030] Furthermore, the process control unit is also used to determine whether to adjust the single sliding distance of the feed slide, wherein:

[0031] The process control unit calculates the angle standard deviation according to the characteristic characterization angle at several moments, and if the angle standard deviation exceeds a preset angle standard deviation reference value, the process control unit determines to adjust the single sliding distance of the feed slide.

[0032] Furthermore, the process control unit is used to adjust the single sliding distance of the feed slide, wherein:

[0033] The process control unit obtains in advance a target machining trajectory of the grinding head machining unit for the workpiece to be machined within a machining feature cycle, determines a single sliding distance corresponding to the target machining trajectory at a number of moments, and adjusts the single sliding distance based on the included angle standard deviation;

[0034] The single sliding distance is negatively correlated with the standard deviation of the angle.

[0035] Compared with the prior art, the beneficial effect of the present invention lies in that the present invention is provided with a frame, a moving component, a workpiece cradle, a stress detection unit and a process control unit, the moving component includes an X-axis moving mechanism, a Y-axis moving mechanism and a Z-axis moving mechanism, the Z-axis moving mechanism includes a milling cutter processing unit and a grinding head processing unit, and the workpiece cradle carries the workpiece to be processed, so as to realize the coordinated cooperation of the axes of different processing process units such as the milling cutter processing unit and the grinding head processing unit, thereby accelerating the processing efficiency, and determining the stress unit vector according to the contact stress conditions at both ends of the support frame of the workpiece cradle through the process control unit, and adjusting the single sliding distance of the feed slide according to the changes of the stress unit vector in the spatial dimension and the time dimension, thereby realizing the adaptive adjustment of the processing parameters of the special processing time period according to the real-time analysis results of the processing process parameters, thereby improving the processing effect and processing accuracy of thin-walled workpieces.

[0036] Furthermore, the present invention constructs a three-dimensional processing space through the cooperation of X-axis, Y-axis, and Z-axis moving mechanisms. The X-axis moving mechanism enables the X-axis slide saddle to move along the slide rail at the front of the beam, the Y-axis moving mechanism allows the Y-axis slide saddle to move on the slide rail on the upper surface of the base, and the Z-axis moving mechanism carries the milling cutter processing unit and the grinding head processing unit respectively through the Z-axis first slide saddle and the Z-axis second slide saddle to move along the slide rail on the surface of the X-axis slide saddle. This multi-axis linkage method provides a rich motion trajectory for the processing tool, allowing the machine tool to process workpieces of complex shapes and meet diverse processing needs.

[0037] Furthermore, the present invention realizes the rotation of the grinding head and the revolution with adjustable circumferential radius through the grinding head revolution axis, feed slide and grinding head rotation axis in the grinding head processing unit. It can be understood that when processing thin-walled workpieces, excessive grinding force may cause deformation or warping of the thin-walled part. By accurately controlling the radial feed amount of the grinding head, fine grinding depth adjustment can be achieved to avoid irreversible deformation of the thin-walled workpiece due to excessive grinding force. The circumferential radius of revolution is determined according to the sliding distance of the feed slide, so that the grinding head can flexibly adjust the revolution radius when processing thin-walled workpieces, which can avoid a large impact on the thin-walled workpiece due to sudden changes in processing parameters and ensure the stability of the processing process.

[0038] Furthermore, the present invention represents the real-time situation of the contact stress between the rotating shaft and the bearing in the form of a vector. It can be understood that during the processing, the stress state will continue to change with the progress of the processing. The stress unit vector can capture these changes in real time and intuitively show the distribution characteristics of the contact stress in the contact area. In different processing stages, the change of the stress unit vector can reflect the change of stress distribution, and then, in the long and complex processing process, the real-time analysis of the processing parameters is realized.

[0039] Furthermore, the present invention selects the processing characteristic cycle during the processing of thin-walled parts. It is understandable that thin-walled workpieces are very easy to deform due to stress. By determining the processing characteristic cycle, the change of the stress unit vector in the time dimension can be grasped in real time, and then the stress state change trend of the thin-walled parts at different times can be understood. When the maximum angle exceeds the angle threshold, it indicates that the part may have a greater deformation risk within the processing characteristic cycle, which is convenient for timely adjustment of processing parameters to reduce part deformation. Furthermore, it realizes the adaptive adjustment of processing parameters in special processing time periods according to the real-time analysis results of the processing process parameters, thereby improving the processing effect and processing accuracy of thin-walled workpieces.

[0040] Furthermore, the present invention determines whether to adjust the single sliding distance of the feed slide by determining the characteristic characterization angle of the stress unit vector in the spatial dimension. It can be understood that when thin-walled parts are being processed, the stress distribution at both ends of the support frame may be uneven. By determining the characteristic characterization angle and the standard deviation of the angle, the difference in stress distribution can be reflected. When the standard deviation of the angle exceeds the reference value, it means that the stress distribution difference is large. Adjusting the single sliding distance of the feed slide can make the processing force of the grinding head on the part more reasonable, avoid the impact of uneven stress, and reduce the deformation of the part caused by uneven stress. Furthermore, it realizes the adaptive adjustment of the processing parameters of the special processing time period according to the real-time analysis results of the processing process parameters, thereby improving the processing effect and processing accuracy of thin-walled workpieces. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 It is a structural schematic diagram of a multi-axis compound machining machine tool according to an embodiment of the present invention;

[0042] Figure 2 It is a structural schematic diagram of a grinding head processing unit according to an embodiment of the present invention;

[0043] Figure 3 It is a structural schematic diagram of a milling cutter processing unit according to an embodiment of the present invention;

[0044] Figure 4 This is a schematic diagram of the structure of a workpiece cradle according to an embodiment of the present invention;

[0045] Figure 5A logic flow chart of a process control unit according to an embodiment of the present invention determining whether a preset monitoring cycle is a processing feature cycle;

[0046] In the figure, 1-base, 2-crossbeam, 3-X-direction slide saddle, 31-X-direction first slide rail, 32-X-direction second slide rail, 33-X-direction third slide rail, 34-driving motor, 4-Y-direction slide saddle, 5-Z-direction first slide saddle, 51-turntable, 52-tool spindle, 6-Z-direction second slide saddle, 61-grinding head, 62-feed slide, 63-grinding head revolution axis, 64-grinding head rotation axis, 7-support frame, 8-cradle body, 9-tool magazine for tool change, 10-workpiece spindle. DETAILED DESCRIPTION

[0047] In order to make the objects and advantages of the present invention more clearly understood, the present invention is further described below in conjunction with embodiments; it should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0048] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the protection scope of the present invention.

[0049] It should be noted that, in the description of the present invention, terms such as "upper", "lower", "inside" and "outside" indicating directions or positional relationships are based on the directions or positional relationships shown in the drawings. This is only for the convenience of description and does not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation on the present invention.

[0050] In addition, it should be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "installation" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0051] See also Figures 1 to 4 As shown, Figure 1 is a schematic structural diagram of a multi-axis compound machining machine tool according to an embodiment of the present invention, Figure 2 is a schematic structural diagram of a grinding head processing unit according to an embodiment of the present invention, Figure 3 is a schematic structural diagram of a milling cutter processing unit according to an embodiment of the present invention, Figure 4 This is a schematic diagram of the structure of a workpiece cradle according to an embodiment of the present invention;

[0052] The multi-axis compound processing machine tool of this embodiment includes:

[0053] The frame comprises a base 1 and a crossbeam 2 arranged on the base 1;

[0054] A moving assembly, including an X-axis moving mechanism, a Y-axis moving mechanism and a Z-axis moving mechanism, wherein the X-axis moving mechanism includes a slide rail arranged at the front of the crossbeam 2 and an X-axis slide saddle 3 arranged on the slide rail;

[0055] The Y-axis moving mechanism comprises a slide rail arranged on the upper surface of the base 1 and a Y-direction slide saddle 4 arranged on the slide rail;

[0056] The Z-axis moving mechanism comprises a Z-direction first slide saddle 5 and a Z-direction second slide saddle 6 respectively arranged on the slide rails on the surface of the X-direction slide saddle 3, a milling cutter processing unit is arranged on the Z-direction first slide saddle 5, and a grinding head processing unit is arranged on the Z-direction second slide saddle 6, and the grinding head processing unit comprises a grinding head 61 and a feed slide 62 driving the grinding head 61 to slide along the radial direction of the grinding head rotation;

[0057] The milling cutter processing unit includes a turntable 51 and a tool spindle 52 installed on the end surface of the turntable 51 .

[0058] A workpiece cradle, which is used to carry the workpiece to be processed, comprises a support frame 7 fixed on the Y-axis slide saddle 4 and a cradle body 8, wherein both ends of the cradle body 8 are connected to the support frame 7 through a rotating shaft and a bearing so that the cradle body 8 rotates about the axis of the rotating shaft;

[0059] Specifically, three X-direction slide rails in the same plane are installed at the front of the beam 2. The installation plane of the X-direction slide rail is perpendicular to the installation surface at the bottom of the beam 2. The three X-direction slide rails are, from bottom to top, the first X-direction slide rail 31, the second X-direction slide rail 32 and the third X-direction slide rail 33. A lead screw and a drive motor 34 for driving the lead screw to rotate are arranged between the first X-direction slide rail 31 and the second X-direction slide rail 32, so that the drive motor 34 drives the X-direction saddle 3 to slide along the first X-direction slide rail 31, the second X-direction slide rail 32 and the third X-direction slide rail 33.

[0060] Stress detection units are respectively arranged at both ends of the support frame 7 to obtain the contact stress value between the bearing and the sleeve;

[0061] A process control unit is respectively connected to the stress detection unit and the moving component, and is used to determine the stress unit vector according to the contact stress conditions at both ends of the support frame 7 and adjust the single sliding distance of the feed slide 62 according to the changes of the stress unit vector in the spatial dimension and the time dimension.

[0062] In practice, the single sliding distance of the feed slide 62 refers to the straight-line distance moved by the feed slide 62 each time it slides along the radial direction of the rotation of the grinding head during the processing. It can be understood that the workpiece processing includes rough grinding and fine grinding, and the circumferential radius of the revolution of the grinding head 61 can be adjusted according to the processing requirements to ensure the uniform distribution of the grinding force. In the rough grinding stage, a larger single sliding distance can be set to improve the material removal rate; in the fine grinding stage, a smaller single sliding distance is set to ensure the surface quality. The single sliding distance of the feed slide 62 in different processing time periods during the rough grinding and fine grinding processes is pre-programmed according to the processing requirements of rough grinding and fine grinding. This is a prior art and will not be repeated here.

[0063] Specifically, the stress detection unit may be a strain gauge stress sensor. During use, the strain gauge on the strain gauge stress sensor is deformed, thereby causing the resistance value of the strain gauge to change. The corresponding stress value is calculated by measuring the change in resistance value. This is a prior art and will not be described in detail here.

[0064] Specifically, the present invention does not limit the specific structure of the process control unit, which itself can be constructed using logic components. The logic components can be field programmable logic components, microprocessors, processors used in computers, etc., which will not be repeated here.

[0065] Specifically, the present invention constructs a three-dimensional processing space through the cooperation of X-axis, Y-axis, and Z-axis moving mechanisms. The X-axis moving mechanism enables the X-axis slide 3 to move along the slide rail in front of the beam 2, and the Y-axis moving mechanism allows the Y-axis slide 4 to move on the slide rail on the upper surface of the base 1. The Z-axis moving mechanism carries the milling cutter processing unit and the grinding head processing unit to move along the slide rail on the surface of the X-axis slide 3 through the Z-axis first slide 5 and the Z-axis second slide 6. This multi-axis linkage method provides a rich motion trajectory for the processing tool, so that the machine tool can process workpieces of complex shapes and meet diverse processing needs.

[0066] Specifically, a tool change magazine 9 for storing milling cutters is provided on one side of the crossbeam 2 close to the milling cutter processing unit.

[0067] In practice, the tool magazine 9 can adopt a disc-type design to store multiple tools. The tool is taken out from the magazine by a robotic arm and automatically installed in the milling cutter processing unit. The computer-controlled intelligent selection of the required processing tools is an existing technology and will not be repeated here.

[0068] Please continue reading Figure 3As shown, it is a schematic diagram of the structure of the milling cutter processing unit according to an embodiment of the present invention, the grinding head processing unit further includes a grinding head revolution axis 63 and a grinding head rotation axis 64, the grinding head revolution axis 63 drives the grinding head 61 on the feed slide 62 to revolve with the axis center line of the grinding head revolution axis 63 as a reference;

[0069] The grinding head self-rotating shaft 64 is disposed on the feed slide 62 to drive the grinding head 61 to rotate with the axis of the grinding head self-rotating shaft 64 as a reference;

[0070] The circumferential radius of the revolution is determined according to the sliding distance of the grinding head 61 driven by the feed slide 62 along the radial direction of the grinding head rotation.

[0071] Specifically, the present invention realizes the rotation of the grinding head 61 and the revolution with adjustable circumferential radius through the grinding head revolution axis 63, the feed slide 62 and the grinding head rotation axis 64 in the grinding head processing unit. It can be understood that when processing thin-walled workpieces, excessive grinding force may cause deformation or warping of the thin-walled part. By accurately controlling the radial feed amount of the grinding head 61, fine grinding depth adjustment can be achieved to avoid irreversible deformation of the thin-walled workpiece due to excessive grinding force. The circumferential radius of revolution is determined according to the sliding distance of the feed slide 62, so that the grinding head 61 can flexibly adjust the revolution radius when processing thin-walled workpieces, which can avoid a large impact on the thin-walled workpiece due to sudden changes in processing parameters and ensure the stability of the processing process.

[0072] Please continue reading Figure 4 As shown, it is a schematic structural diagram of a workpiece cradle according to an embodiment of the present invention. A workpiece spindle 10 for carrying the workpiece to be processed is also provided on the cradle body 8, so that the workpiece spindle 10 drives the workpiece to be processed to rotate.

[0073] Specifically, the process control unit is used to determine the stress unit vector according to the contact stress value between the rotating shaft and the bearing;

[0074] The vector end point of the stress unit vector is the position where the maximum contact stress is located in the contact position between the rotating shaft and the bearing, and the vector starting position of the stress unit vector is the center position of the bearing.

[0075] Specifically, the present invention represents the real-time situation of the contact stress between the rotating shaft and the bearing in the form of a vector. It can be understood that during the processing, the stress state will continue to change with the progress of the processing. The stress unit vector can capture these changes in real time and intuitively show the distribution characteristics of the contact stress in the contact area. In different processing stages, the change of the stress unit vector can reflect the change of stress distribution, and then, in the long and complex processing process, the real-time analysis of the processing parameters is realized.

[0076] Specifically, the process control unit is used to determine the change of the stress unit vector in the time dimension, wherein:

[0077] The process control unit is used to obtain stress unit vectors corresponding to several moments in a preset monitoring period, and determine the maximum angle between two stress unit vectors according to the stress unit vectors corresponding to the several moments.

[0078] In this embodiment, the duration of the preset monitoring cycle may be 5 seconds, and the corresponding stress unit vector is acquired every 1 second within the preset monitoring cycle of 5 seconds. The interval duration between adjacent preset monitoring cycles may be 3 seconds.

[0079] See also Figure 5 As shown, it is a logic flow chart of the process control unit of an embodiment of the present invention for determining whether a preset monitoring cycle is a processing feature cycle. The process control unit is also used to determine whether the preset monitoring cycle is a processing feature cycle, wherein:

[0080] If the maximum angle meets the characteristic phenomenon screening condition, the process control unit determines that the preset monitoring period is a processing characteristic period;

[0081] If the maximum angle does not meet the characteristic phenomenon screening condition, the process control unit determines that the preset monitoring period is not a processing characteristic period;

[0082] The characteristic phenomenon screening condition is that the maximum angle between two stress unit vectors at any end of the support frame 7 within a preset monitoring period exceeds a preset angle threshold.

[0083] Specifically, technicians in this field can determine the preset angle threshold based on the processing precision requirements. The higher the precision requirement, the smaller the angle threshold. In this embodiment, the angle threshold value range is [3°, 8°]. Preferably, the angle threshold can be 5°.

[0084] Specifically, the present invention selects the processing characteristic cycle during the processing of thin-walled parts. It is understandable that thin-walled workpieces are very easy to deform due to stress. By determining the processing characteristic cycle, the change of the stress unit vector in the time dimension can be grasped in real time, and then the stress state change trend of the thin-walled parts at different times can be understood. When the maximum angle exceeds the angle threshold, it indicates that the part may have a large deformation risk within the processing characteristic cycle, which is convenient for timely adjustment of processing parameters to reduce part deformation. Furthermore, it realizes the adaptive adjustment of processing parameters in special processing time periods according to the real-time analysis results of the processing process parameters, thereby improving the processing effect and processing accuracy of thin-walled workpieces.

[0085] Specifically, the process control unit is also used to determine the characteristic characterization angle of the stress unit vector in the spatial dimension, wherein,

[0086] Under the condition that the preset monitoring period is determined to be a processing characteristic period, the process control unit obtains the stress unit vectors corresponding to each end of the support frame 7 at several moments within the preset monitoring period, and determines the angle between the two stress unit vectors at both ends of the support frame 7 at the same moment as the characteristic characterization angle.

[0087] Specifically, the process control unit is also used to determine whether to adjust the single sliding distance of the feed slide 62, wherein:

[0088] The process control unit calculates the angle standard deviation according to the characteristic characterization angle at several moments, and if the angle standard deviation exceeds a preset angle standard deviation reference value, the process control unit determines to adjust the single sliding distance of the feed slide 62;

[0089] If the angle standard deviation does not exceed the preset angle standard deviation reference value, the process control unit determines not to adjust the single sliding distance of the feed slide 62;

[0090] Specifically, technical personnel in this field can set the angle standard deviation reference value according to the processing precision requirement. The higher the precision requirement, the smaller the angle standard deviation reference value. In this embodiment, the angle standard deviation reference value ranges from [2°, 5°]. Preferably, the angle standard deviation reference value can be 3°.

[0091] Specifically, the present invention determines whether to adjust the single sliding distance of the feed slide 62 by determining the characteristic characterization angle of the stress unit vector in the spatial dimension. It can be understood that when thin-walled parts are being processed, the stress distribution at both ends of the support frame 7 may be uneven. By determining the characteristic characterization angle and the standard deviation of the angle, the difference in stress distribution can be reflected. When the standard deviation of the angle exceeds the reference value, it means that the stress distribution difference is large. Adjusting the single sliding distance of the feed slide 62 can make the grinding head 61 more reasonable in processing the parts, avoid the impact of uneven stress, and reduce the deformation of parts caused by uneven stress. Furthermore, it realizes the adaptive adjustment of the processing parameters of the special processing time period according to the real-time analysis results of the processing process parameters, thereby improving the processing effect and processing accuracy of thin-walled workpieces.

[0092] Specifically, the process control unit is used to adjust the single sliding distance of the feed slide 62, wherein:

[0093] The process control unit obtains in advance a target machining trajectory of the grinding head machining unit for the workpiece to be machined within a machining feature cycle, determines a single sliding distance corresponding to the target machining trajectory at a number of moments, and adjusts the single sliding distance based on the included angle standard deviation;

[0094] The single sliding distance is negatively correlated with the standard deviation of the angle.

[0095] In implementation, if the process control unit determines that the single sliding distances corresponding to the five moments of the target machining trajectory within the machining feature cycle with a cycle length of 5s are: 2.5mm, 2.8mm, 3.2mm, 1.8mm and 3mm respectively;

[0096] If the standard deviation of the angle is 3.5°, the single sliding distances corresponding to the five moments can be multiplied by the first adjustment coefficient A1=0.8, and the single sliding distances corresponding to the five moments are: 2 mm, 2.24 mm, 2.56 mm, 1.44 mm and 2.4 mm respectively;

[0097] If the standard deviation of the angle is 4°, the single sliding distances corresponding to the five moments can be multiplied by the second adjustment coefficient A2=0.7, and the single sliding distances corresponding to the five moments are: 1.75 mm, 1.96 mm, 2.24 mm, 1.26 mm and 2.1 mm respectively;

[0098] Of course, for those skilled in the art, other negative correlation calculation methods suitable for processing the negative correlation between the single sliding distance and the standard deviation of the angle in this embodiment can be selected as the methods of this embodiment. In addition, in order not to affect the final grinding effect of the grinding head, the grinding time can be extended to ensure that the grinding head 61 grinds the workpiece to be processed to the target effect with a smaller single sliding distance. This is well known to those skilled in the art and will not be repeated here.

[0099] So far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

[0100] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A multi-axis compound machining machine tool, characterized in that: include: A frame, comprising a base and a crossbeam 2 arranged on the base; A moving assembly, comprising an X-axis moving mechanism, a Y-axis moving mechanism and a Z-axis moving mechanism, wherein the X-axis moving mechanism comprises a slide rail arranged at the front of the crossbeam and an X-axis slide saddle arranged on the slide rail; The Y-axis moving mechanism comprises a slide rail arranged on the upper surface of the base and a Y-direction slide saddle arranged on the slide rail; The Z-axis moving mechanism comprises a Z-direction first slide saddle and a Z-direction second slide saddle respectively arranged on the slide rails on the surface of the X-direction slide saddle, a milling cutter processing unit is arranged on the Z-direction first slide saddle, and a grinding head processing unit is arranged on the Z-direction second slide saddle, and the grinding head processing unit comprises a grinding head and a feed slide table driving the grinding head to slide along the radial direction of the rotation of the grinding head; A workpiece cradle, which is used to carry the workpiece to be processed, comprises a support frame fixed on the Y-axis slide saddle and a cradle body, wherein both ends of the cradle body are connected to the support frame through a rotating shaft and a bearing so that the cradle body rotates about the axis of the rotating shaft; Stress detection units are respectively arranged at both ends of the support frame to obtain the contact stress value between the bearing and the sleeve; A process control unit is respectively connected to the stress detection unit and the moving component, and is used to determine the stress unit vector according to the contact stress conditions at both ends of the support frame and adjust the single sliding distance of the feed slide according to the changes of the stress unit vector in the spatial dimension and the time dimension.

2. The multi-axis compound machining machine tool according to claim 1, characterized in that: A tool changing magazine for storing milling cutters is also arranged on one side of the crossbeam close to the milling cutter processing unit.

3. The multi-axis compound machining machine tool according to claim 1, characterized in that: The grinding head processing unit further includes a grinding head revolution axis and a grinding head rotation axis, wherein the grinding head revolution axis drives the grinding head on the feed slide to revolve with the axis center line of the grinding head revolution axis as a reference; The grinding head rotation shaft is arranged on the feed slide to drive the grinding head to rotate with the axis of the grinding head rotation shaft as the reference; The circumferential radius of the revolution is determined according to the sliding distance of the grinding head driven by the feed slide along the radial direction of the grinding head's rotation.

4. The multi-axis compound machining machine tool according to claim 1, characterized in that: The cradle body is also provided with a workpiece spindle for carrying the workpiece to be processed, so that the workpiece spindle drives the workpiece to be processed to rotate.

5. The multi-axis compound machining machine tool according to claim 1, characterized in that: The process control unit is used to determine the stress unit vector according to the contact stress value between the rotating shaft and the bearing; The vector end point of the stress unit vector is the position where the maximum contact stress is located in the contact position between the rotating shaft and the bearing, and the vector starting position of the stress unit vector is the center position of the bearing.

6. The multi-axis compound machining machine tool according to claim 5, characterized in that: The process control unit is used to determine the change of the stress unit vector in the time dimension, wherein: The process control unit is used to obtain stress unit vectors corresponding to several moments in a preset monitoring period, and determine the maximum angle between two stress unit vectors according to the stress unit vectors corresponding to the several moments.

7. The multi-axis compound machining machine tool according to claim 6, characterized in that: The process control unit is also used to determine whether the preset monitoring cycle is a processing feature cycle, wherein: If the maximum angle meets the characteristic phenomenon screening condition, the process control unit determines that the preset monitoring period is a processing characteristic period; The characteristic phenomenon screening condition is that the maximum angle between two stress unit vectors at any end of the support frame within a preset monitoring period exceeds a preset angle threshold.

8. The multi-axis compound machining machine tool according to claim 7, characterized in that: The process control unit is also used to determine the characteristic characterization angle of the stress unit vector in the spatial dimension, wherein, Under the condition that the preset monitoring period is determined to be a processing characteristic period, the process control unit obtains the stress unit vectors corresponding to each end of the support frame at several moments within the preset monitoring period, and determines the angle between the two stress unit vectors at the two ends of the support frame at the same moment as the characteristic characterization angle.

9. The multi-axis compound machining machine tool according to claim 8, characterized in that: The process control unit is also used to determine whether to adjust the single sliding distance of the feed slide, wherein: The process control unit calculates the angle standard deviation according to the characteristic characterization angle at several moments, and if the angle standard deviation exceeds a preset angle standard deviation reference value, the process control unit determines to adjust the single sliding distance of the feed slide.

10. The multi-axis compound machining machine tool according to claim 9, characterized in that: The process control unit is used to adjust the single sliding distance of the feed slide, wherein: The process control unit obtains in advance a target machining trajectory of the grinding head machining unit for the workpiece to be machined within a machining feature cycle, determines a single sliding distance corresponding to the target machining trajectory at a number of moments, and adjusts the single sliding distance based on the included angle standard deviation; The single sliding distance is negatively correlated with the standard deviation of the angle.

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