A large-pitch coaxial hole intelligent machining device and a machining method

Abstract

The application provides a large-pitch coaxial hole intelligent machining device and a machining method. The coaxial hole intelligent machining device comprises a numerical control boring machine, the numerical control boring machine comprises a workbench and a boring bar, and the boring bar is provided with a boring tool; the coaxial hole intelligent machining device further comprises a circular positioning instrument and a controller; the circular positioning instrument comprises a fixed group and a moving group, the fixed group is provided with at least two fixed positioning components, the moving group is provided with at least one moving positioning component, both the fixed group and the moving group are provided with a contact part, a pressure sensor and a driving mechanism, the driving mechanism can drive the contact part to be close to or away from the rotation axis of the boring bar, the pressure sensor detects the contact pressure of the contact part and the boring bar or the machined hole, and the controller can read the value of the pressure sensor and control the driving mechanism. The device can accurately determine the relative position of the boring bar and the axis of the hole to be machined through multi-point positioning circumferential constraint, and significantly improves the reliability and repeat accuracy of coaxiality positioning under large-pitch working conditions.

Description

Technical Field

[0001] The invention relates to the field of coaxial hole processing technology, specifically to an intelligent processing device and method for coaxial holes with large hole spacing. Background Technology

[0002] For long-shaft and extra-long-shaft components (such as large-span roller supports), the center distance between the bearing holes or bearing housing mounting holes at both ends can reach 2 meters, 3 meters or even longer. Such components place stringent requirements on the coaxiality and straightness accuracy of the rotation axes of the two holes, which directly determines the operational stability and service life of the entire system.

[0003] Existing metal cutting equipment (such as horizontal boring machines and gantry boring machines) struggles to achieve continuous, single-cut machining of the surfaces of two holes with large hole spacing. Conventional machining processes typically involve machining one hole first, then re-clamping the component by turning it 180°, re-setting the tool, or moving the side hole to be machined to the machining position on a gantry boring and milling machine and adjusting the boring tool's 180° orientation. All of these methods introduce linear table displacement errors, making it difficult to meet high coaxiality accuracy requirements, and consequently directly affecting the operational accuracy and performance of the mechanical system. Therefore, innovation in processes and equipment technology to solve the challenge of high-precision coaxial machining of such large-hole-spacing hole systems has become a pressing technological need for the industry. Summary of the Invention

[0004] In view of the shortcomings of the existing technology, the purpose of the invention is to propose an intelligent processing device and method for coaxial holes with large hole spacing, so as to solve the problems mentioned in the background section above.

[0005] The invention is achieved through the following technical solution:

[0006] A large-pitch coaxial hole intelligent machining device includes a CNC boring machine, the CNC boring machine includes a worktable and a boring bar, the boring bar is equipped with a boring tool, and also includes a circular positioning device and a controller;

[0007] The circular positioning instrument includes a fixed group and a movable group. The fixed group has at least two fixed positioning components, and the movable group has at least one movable positioning component. The movable positioning component is movable along the direction of approaching or moving away from the rotation axis of the boring bar.

[0008] Both the fixed positioning component and the mobile positioning component are respectively equipped with a contact part, a pressure sensor and a driving mechanism;

[0009] The driving mechanism is used to drive the corresponding contact part to move in a direction close to or away from the rotation axis of the boring bar, and the pressure sensor is used to detect the contact pressure between the contact part and the boring bar or the machining hole;

[0010] The controller is electrically connected to the pressure sensor and the drive mechanism. The controller is used to read the detection value of the pressure sensor and control the drive mechanism to perform extension and retraction actions according to the detection value.

[0011] Furthermore, the number of fixed positioning components is two, and the number of mobile positioning components is one.

[0012] Furthermore, the included angle between the central axes of two adjacent fixed positioning components is 120°, and the included angle between the central axes of adjacent fixed positioning components and mobile positioning components is 120°.

[0013] Furthermore, the circular positioning device also includes a fixed frame and a rotating frame. One end of the rotating frame is hinged to the corner of the fixed frame. The fixed positioning component is fixedly installed on the fixed frame, and the moving positioning component is fixedly installed on the rotating frame.

[0014] Furthermore, both the fixed positioning component and the mobile positioning component are equipped with lead screws, and the lead screws satisfy the following:

[0015] In the formula, Let $\mathbf$ be the lead of the leadscrew. The diameter of the lead screw is given.

[0016] On the other hand, the present invention provides a processing method based on the intelligent coaxial hole processing device described in any one of the above claims, comprising the following steps:

[0017] S1. Determine the center axis of the first hole to be machined, align the rotation axis of the boring bar with the center axis of the first hole, and adjust the radial distance between the boring tool cutting edge and the rotation axis of the boring bar according to the diameter of the first hole.

[0018] S2. Drive the contact part of the circular positioning instrument to move and abut against the outer circumferential surface of the boring bar, so that the detection values ​​of each pressure sensor are within the preset threshold range;

[0019] S3. Record the position coordinates of the contact part and the detected pressure values ​​of each pressure sensor, and then control the contact part to move away from the working motion area of ​​the boring bar;

[0020] S4. Boring the first hole to the required accuracy;

[0021] S5. Control the movement of the contact part according to the coordinate values ​​or coordinate difference between the first hole and the second hole in the Y-axis direction of the worktable, and the corresponding relationship of the longitudinal movement error compensation table of the worktable.

[0022] S6. Adjust the position of the boring bar so that the detected pressure values ​​of each pressure sensor fall into the same preset threshold range as in step S3, and then control the contact part to move away from the working motion area of ​​the boring bar;

[0023] S7. Boring the second hole to the required accuracy.

[0024] Furthermore, step S3 includes the following sub-steps:

[0025] S31. Determine the operating threshold range of the pressure sensor based on the material strength of the boring bar and the contact part. ,in:

[0026] ;

[0027] In the formula, δ is the material strength reduction factor, which is used to reduce the material's ultimate pressure value to a safe working reference pressure; This represents the ultimate pressure value, which is the strength limit of the material. This is the allowable deviation of the pressure threshold, used to limit the range of fluctuation of the working pressure.

[0028] S32. Check if each contact part is in the working position. If it is not in the working position, continue to adjust it to the working position.

[0029] ;

[0030] S33. If the contact part is already in the working position, start pressure detection and adjust the position of the contact part until the detection value of the pressure sensor falls within the working threshold range.

[0031] S34. Record the position coordinates of each contact part, denoted as:

[0032] ,

[0033] In the formula: This indicates the spatial location of the first contact point; Indicates the spatial location of the second contact point; This indicates the spatial location of the third contact point.

[0034] Furthermore, the longitudinal movement error compensation table for the worktable in step S5 specifically includes:

[0035] S51. Record the deviation of the worktable along the Y-axis and parallel to the XOZ plane as:

[0036] ;

[0037] ;

[0038] In the formula, The total number of experiments, For the first This experiment; This indicates the offset along the X-axis at the Y-axis position; This indicates the offset along the Z-axis at the Y-axis position;

[0039] S52. Measure the position points of each Y-axis of the worktable to obtain the longitudinal movement error compensation table of the worktable.

[0040] Furthermore, in step S5, the amount of extension / retraction of the contact portion is... The calculation formula is:

[0041] ;

[0042] In the formula, Indicates the first One contact part, This indicates the outer radius of the boring bar used to machine the first hole. This indicates the outer radius of the boring bar used to machine the second hole. This represents the coordinate difference between the first hole and the second hole along the X-axis of the worktable. This represents the coordinate difference between the first hole and the second hole in the Z-axis direction of the worktable. Indicates the first The initial extension / retraction direction angle of the contact part during the machining of the first hole;

[0043] according to The positive and negative values, if If the value is greater than 0, the control contact part of the drive mechanism extends towards the direction of rotation of the boring bar; if If the value is less than 0, the control contact part of the drive mechanism retracts in a direction away from the rotation axis of the boring bar.

[0044] On the other hand, the present invention provides a processing method based on the intelligent coaxial hole processing device described in any one of the above claims, comprising the following steps:

[0045] S1. Determine the center axis of the first hole to be machined, align the rotation axis of the boring bar with the center axis of the first hole, and adjust the radial distance between the boring tool cutting edge and the rotation axis of the boring bar according to the diameter of the first hole.

[0046] S2. Rough boring of the first hole;

[0047] S3. Drive the contact part of the circular positioning instrument to move and abut against the inner circumferential surface of the first hole, so that the detection values ​​of each pressure sensor are within the preset threshold range.

[0048] S4. Record the position coordinates of the contact part and the detected pressure values ​​of each pressure sensor, and then control the contact part to move away from the working motion area of ​​the boring bar;

[0049] S5. Boring the first hole to the required accuracy;

[0050] S6. Determine the center axis of the second hole to be machined, align the rotation axis of the boring bar with the center axis of the second hole, and adjust the radial distance between the boring tool cutting edge and the rotation axis of the boring bar according to the diameter of the second hole.

[0051] S7. Rough boring of the second hole;

[0052] S8. Calculate the coordinate values ​​or coordinate difference between the first hole and the second hole in the Y-axis direction of the worktable, and control the movement of the contact part according to the correspondence between the Y-axis coordinate values ​​or coordinate difference and the longitudinal movement error compensation table of the worktable.

[0053] S9. Adjust the position of the workpiece to be processed so that the detected pressure values ​​of each pressure sensor fall into the same preset threshold range as in step S4, and then control the contact part to move away from the working motion area of ​​the boring bar.

[0054] S10. Boring the second hole to the required accuracy.

[0055] The beneficial effects of the invention are as follows: A smart machining device for coaxial holes with large hole spacing includes a CNC boring machine, which includes a worktable and a boring bar, the boring bar being equipped with a boring tool, and also includes a circular positioning device and a controller; the circular positioning device includes a fixed group and a moving group, the fixed group having at least two fixed positioning components, and the moving group having at least one moving positioning component, the moving positioning component being movable along the direction approaching or away from the boring bar's rotation axis; each of the fixed positioning component and the moving positioning component is respectively equipped with a contact part, a pressure sensor, and a drive mechanism; the drive mechanism is used to drive the corresponding contact part to displace along the direction approaching or away from the boring bar's rotation axis, the pressure sensor is used to detect the contact pressure between the contact part and the boring bar or the machining hole; the controller is electrically connected to the pressure sensor and the drive mechanism, the controller being used to read the detection value of the pressure sensor and control the drive mechanism to perform extension and retraction actions according to the detection value. This device, by setting at least two fixed positioning components and at least one movable positioning component, uses a multi-point positioning method to circumferentially constrain the boring bar or the machined hole. It can quickly and stably determine the relative position of the boring bar's rotation axis and the axis of the hole to be machined, significantly improving the reliability and repeatability of coaxiality positioning under large hole spacing conditions. Attached Figure Description

[0056] Figure 1 This is a perspective view of the circular positioning instrument in the coaxial hole intelligent machining device of the present invention.

[0057] Figure 2 This is a perspective view of the worktable and processing components in the intelligent coaxial hole processing device of the present invention.

[0058] Figure 3 This is a perspective view of the fixed positioning component or the movable positioning component in the intelligent coaxial hole processing device of the present invention.

[0059] Figure 4 This is a three-dimensional schematic diagram of the processing method of the coaxial hole intelligent processing device of the present invention, showing the processing of the first hole and the second hole.

[0060] Figure 5 This is a front view of the processing method based on the intelligent coaxial hole processing device of the present invention, showing the processing of the first hole and the second hole.

[0061] Figure 6 This is another front view of the processing method based on the intelligent coaxial hole processing device of the present invention, showing the processing of the first hole and the second hole.

[0062] The above figures include the following reference numerals:

[0063] 1. Workbench; 2. Machining assembly; 21. Boring bar; 3. Circular positioning device; 31. Fixed positioning assembly; 311. Contact part; 312. Drive mechanism; 313. Pressure sensor; 314. Lead screw; 315. Moving nut; 32. Moving positioning assembly; 33. Fixed frame; 34. Rotating frame; 35. Clearance opening. Detailed Implementation

[0064] To make the objectives, technical solutions, and advantages of the embodiments of the invention clearer, the technical solutions of the embodiments will be clearly and completely described below with reference to the accompanying drawings. It should be noted that the description of these embodiments is intended to aid in understanding the invention but does not constitute a limitation thereof. Furthermore, the technical features involved in the various embodiments of the invention described below can be combined with each other as long as they do not conflict with each other.

[0065] A coaxial hole intelligent machining device with large hole spacing includes a CNC boring machine. In the prior art, the CNC boring machine includes a worktable 1 and a machining component 2. The machining component 2 is equipped with a boring bar 21, and a boring tool is mounted on the boring bar 21. In actual machining, the boring tool with different extension lengths can be replaced according to the hole diameter requirements, or the installation position of the boring tool can be directly fine-tuned to adjust the radial distance between the boring tool cutting edge and the rotation axis of the boring bar 21, thereby adapting to boring operations of different hole diameters.

[0066] For machining large-pitch coaxial holes in long and extra-long shaft components, the industry mainly adopts two machining methods: First, referring to... Figure 2In one operation, the machining component 2 can slide and feed along the Y-axis of the worktable 1. During the boring process, the component to be machined is kept fixed. The displacement stroke of the machining component 2 is precisely controlled by the machine tool controller to complete the coaxial hole boring process in sequence. In another operation, the machining component 2 remains stationary and fixed. The component to be machined is driven to slide and feed along the Y-axis of the worktable 1 by the drive mounting table. The displacement stroke of the mounting table is precisely controlled by the machine tool controller to complete the coaxial hole boring process in sequence.

[0067] Among them, the Y-axis movement control structure, guide structure, boring tool radial adjustment mechanism, etc. of machining component 2 or mounting table are all implemented using mature existing technologies in this field. For example, linear guide rails can be used in conjunction with servo motor drive to achieve precise Y-axis feed, and precision lead screw 314 or slider mechanism can be used to achieve radial micro-adjustment of the boring tool. These will not be elaborated further here.

[0068] Reference Figure 1 As shown, a large-pitch coaxial hole intelligent machining device also includes a circular positioning instrument 3 and a controller. In the figure, the black lines represent the fixed frame 33 and the rotating frame 34 of the circular positioning instrument 3, the red lines represent the boring bar 21, and the blue lines represent the moving positioning component 32 and the fixed positioning component 31, respectively. Specifically:

[0069] The circular positioning instrument 3 includes a fixed group and a movable group. The fixed group is provided with at least two fixed positioning components 31, and the movable group is provided with at least one movable positioning component 32. The movable positioning component 32 is movable along the direction close to or away from the rotation axis of the boring bar 21.

[0070] The fixed positioning component 31 and the mobile positioning component 32 are each equipped with a contact part 311, a pressure sensor 313 and a drive mechanism 312.

[0071] The drive mechanism 312 is used to drive the corresponding contact part 311 to move in a direction close to or away from the rotation axis of the boring bar 21, and the pressure sensor 313 is used to detect the contact pressure between the contact part 311 and the boring bar 21 or the machining hole;

[0072] The controller is electrically connected to the pressure sensor 313 and the drive mechanism 312. The controller is used to read the detection value of the pressure sensor 313 and control the drive mechanism 312 to perform extension and retraction actions according to the value.

[0073] Example 1

[0074] In this embodiment, the circular positioning device 3 is used for positioning calibration by abutting against the outer peripheral surface of the boring bar 21. The circular positioning device 3 forms at least three contact parts 311 through at least two fixed positioning components 31 and at least one movable positioning component 32. Before processing, the controller controls the operation of each drive mechanism 312 to drive the corresponding contact part 311 to move along the direction close to the rotation axis of the boring bar 21, so that each contact part 311 abuts against the outer peripheral surface of the boring bar 21 at the same time, forming a three-point positioning structure. Using the geometric principle of three points determining a unique center and axis, the current rotation axis position of the boring bar 21 can be accurately determined. Each pressure sensor 313 detects the contact pressure between the contact part 311 and the boring bar 21 in real time. The controller adjusts the extension of the drive mechanism 312 according to the pressure value fed back by the pressure sensor 313, so that the contact pressure between each contact part 311 and the boring bar 21 is kept within a preset threshold range, thereby ensuring stable positioning and reliable coaxiality accuracy of the boring bar 21.

[0075] Example 2

[0076] The difference between Embodiment 2 and Embodiment 1 is that the positioning object of the circular positioning instrument 3 is changed from the outer peripheral surface of the boring bar 21 to the inner wall of the hole to be machined. During machining, the boring bar 21 and the boring tool are first used to rough-bor the first hole or the second hole. After rough boring, the controller controls each drive mechanism 312 to drive the contact part 311 to extend into the rough-bored first hole or the second hole, and moves the contact part 311 along the direction close to the inner wall of the hole until it abuts. Through the three-point contact structure formed by at least two fixed positioning components 31 and at least one moving positioning component 32, the actual center axis of the first hole or the second hole is determined, and the rotation axis of the boring bar 21 is compensated and corrected based on the actual axis. After the correction is completed, the controller controls the contact part 311 to retract and exit the machining area, and then performs semi-finish boring and finish boring on the first hole or the second hole, thereby eliminating the movement error and clamping error of the worktable 1 and improving the coaxiality machining accuracy between the two holes with a large hole distance.

[0077] The number of fixed positioning components 31 is two, and the number of movable positioning components 32 is one. The two fixed positioning components 31 are fixedly positioned relative to the rotation axis of the boring bar 21, and the movable positioning component 32 can be moved and adjusted in the direction of approaching or moving away from the rotation axis of the boring bar 21. Through the cooperation of the two fixed positioning components 31 and the one movable positioning component 32, three-point contact positioning of the outer peripheral surface of the boring bar 21 or the inner wall of the machined hole is achieved.

[0078] The three-point positioning structure, which uses two fixed positioning components 31 and one moving positioning component 32, effectively reduces the overall number of positioning components while meeting the requirements of high-precision coaxial positioning. This simplifies the overall structure of the circular positioning instrument 3, and the reduction in the number of parts directly reduces the manufacturing and material costs of the circular positioning instrument 3. At the same time, it reduces the number of supporting components such as the drive mechanism 312, pressure sensor 313, and contact part 311, further saving costs and improving the economic efficiency of the device.

[0079] The included angle between the central axes of two adjacent fixed positioning components 31 is 120°, and the included angle between the central axes of adjacent fixed positioning components 31 and moving positioning components 32 is 120°, so that the three contact parts 311 are arranged in a uniform circular array around the rotation axis of the boring bar 21 or the central axis of the hole to be processed.

[0080] By arranging the three contact parts 311 evenly at 120° angles, the radial extension and contraction directions of each contact part 311 are symmetrical and the force is balanced. During positioning, the boring bar 21 or the hole wall is subjected to uniform force, which is less prone to wobble and helps to improve positioning stability and coaxiality accuracy. At the same time, the symmetrical and uniform arrangement gives the extension and contraction displacement of each contact part 311 a clear geometric correspondence. This allows the controller to quickly and accurately calculate the extension and contraction compensation of each contact part 311 based on the feedback value of the pressure sensor 313, simplifying the control algorithm and improving the positioning response speed and control accuracy.

[0081] The circular positioning instrument 3 also includes a fixed frame 33 and a rotating frame 34. One end of the rotating frame 34 is hinged to the corner of the fixed frame 33. The fixed positioning component 31 is fixedly installed on the fixed frame 33, and the moving positioning component 32 is fixedly installed on the rotating frame 34. When it is necessary to install or remove the boring bar 21, the rotating frame 34 can be rotated around the hinge point to form an avoidance opening 35 between the rotating frame 34 and the fixed frame 33, providing space for the boring bar 21 to pass through, thus facilitating the smooth passage of the boring bar 21 through the circular positioning instrument 3 for assembly. After the boring bar 21 is assembled in place, the rotating frame 34 is rotated in the opposite direction to reset it, and the three positioning components re-form a closed three-point positioning structure to achieve positioning detection of the boring bar 21 or the machined hole.

[0082] The fixing and closing method of the rotating frame 34 and the fixed frame 33 at the clearance opening 35 can be achieved using existing conventional locking structures. This application does not specifically limit this method, nor does it provide corresponding drawings. An example of an existing locking method is as follows:

[0083] Example 1: The openings of the fixed frame 33 and the rotating frame 34 are respectively provided with elastic buckles and locking grooves. When the rotating frame 34 returns to the closed position, the elastic buckles automatically engage with the locking grooves to achieve quick locking; when it is necessary to open, the buckles can be manually moved to release the lock.

[0084] Example 2: Ear plates are respectively installed at corresponding positions of the open ends of the fixed frame 33 and the rotating frame 34, and coaxial through holes are opened on the ear plates. After the rotating frame 34 is closed, fastening bolts or quick-release screws are used to thread-lock the two through the ear plates to ensure that the frame does not loosen or deflect during the positioning process, and to ensure the angular position accuracy of the three-point positioning assembly.

[0085] Furthermore, both the fixed positioning component 31 and the moving positioning component 32 are respectively equipped with a lead screw 314, which satisfies the following: In the formula, The lead of the lead screw 314 is... The diameter of the lead screw 314 is given.

[0086] In the above scheme: the lead screw 314 adopts a structure design with a small lead and a large screw diameter ratio, and the lead... Under certain conditions, when the lead screw 314 rotates through the circumference arc length Corresponding corner At that time, the axial micro-displacement of the contact portion 311 satisfy:

[0087] ;

[0088] It can be seen that when the lead and the arc length of the rotation angle are fixed, increasing the screw diameter... It can significantly reduce axial micro-displacement This allows for more precise displacement adjustment.

[0089] Therefore, the present invention satisfies the requirements of lead screw 314. The design allows for smaller axial micro-displacement under the same angular arc length, significantly improving the position adjustment accuracy of the contact part 311 and ensuring the coaxial positioning accuracy of the boring bar 21 or the hole to be machined.

[0090] Reference Figure 4 As shown, the fixed positioning component 31 and the moving positioning component 32 have the same structure, differing only in their assembly positions. Their working principle is as follows: The fixed frame 33 or rotating frame of the circular positioning instrument 3 is fixedly connected to the drive mechanism 312. The drive mechanism 312 adopts a micro motor as in the prior art. The drive mechanism 312 drives the lead screw 314 and nut mechanism fixed thereto. The moving nut 315, which cooperates with the lead screw 314, can move forward and backward along the axis. The moving nut 315 is fixedly connected to the contact part 311, which has a spherical structure. The front end of the contact part 311 is a pressure sensor. When the micro motor is working, the moving part of the component moves forward, and the contact ball contacts the workpiece positioning surface. The pressure sensor 313 measures and feeds back the pressure value. The control system controls the rotation and direction of the micro motor according to the set threshold, thereby realizing effective and intelligent adjustment of the contact pressure of the contact ball.

[0091] On the other hand, based on the aforementioned intelligent coaxial hole processing device, the present invention further provides two processing methods, specifically:

[0092] Regarding the processing method of Embodiment 1 above:

[0093] A machining method for a coaxial hole intelligent machining device based on large hole spacing includes the following steps:

[0094] S1. Determine the center axis of the first hole to be machined, align the rotation axis of the boring bar 21 with the center axis of the first hole, and adjust the radial distance between the boring tool cutting edge and the rotation axis of the boring bar 21 according to the diameter of the first hole.

[0095] S2. Drive the contact part 311 of the circular positioning instrument 3 to move and abut against the outer peripheral surface of the boring bar 21, so that the detection values ​​of each pressure sensor 313 are within the preset threshold range;

[0096] S3. Record the position coordinates of the contact part 311 and the detected pressure values ​​of each pressure sensor 313, and then control the contact part 311 to move away from the working motion area of ​​the boring bar 21;

[0097] S4. Boring the first hole to the required accuracy;

[0098] S5. Control the contact part 311 to extend or retract according to the coordinate values ​​or coordinate difference between the first hole and the second hole in the Y-axis direction of the worktable 1 and the corresponding relationship of the longitudinal movement error compensation table of the worktable 1.

[0099] S6. Adjust the position of the boring bar 21 so that the detected pressure value of each pressure sensor 313 falls into the same preset threshold range as in step S3, and then control the contact part 311 to move away from the working movement area of ​​the boring bar 21.

[0100] S7. Boring the second hole to the required accuracy.

[0101] In a preferred embodiment, step S3 includes the following sub-steps:

[0102] S31. Determine the working threshold range of the pressure sensor 313 based on the material strength of the boring bar 21 and the contact part 311. ,in:

[0103] ;

[0104] In the formula, δ is the material strength reduction factor, which is used to reduce the material's ultimate pressure value to a safe working reference pressure; This represents the ultimate pressure value, which is the strength limit of the material. This is the allowable deviation of the pressure threshold, used to limit the range of fluctuation of the working pressure.

[0105] In step S31, the present invention establishes a calculation model for the working threshold range of the pressure sensor 313 based on the material strength of the boring bar 21 and the contact part 311. The safe working reference pressure can be obtained by scientifically reducing the limit pressure value of different materials, avoiding excessive contact pressure that could cause plastic deformation or surface damage to the boring bar 21 or the contact part 311, while preventing insufficient pressure that could lead to positioning failure, thus effectively balancing positioning reliability and structural safety.

[0106] Preferred parameters in this invention: , The above parameters take into account both material safety margin and control accuracy, ensuring that the contact pressure is far below the material's ultimate strength to avoid structural damage, while also retaining a reasonable pressure fluctuation range to adapt to positioning requirements under different working conditions. At the same time, the parameter configuration is simplified, making it easy for industrial promotion and application.

[0107] S32. Check if each contact part 311 is in the working position. If it is not in the working position, continue to adjust it to the working position.

[0108] ;

[0109] In step S32, a position detection unit can be configured in both the fixed positioning component 31 and the mobile positioning component 32, thereby enabling the detection of the position when the first position is reached. The position detection signal of the contact part 311 indicates that it has moved to the preset radial position range.

[0110] The position detection unit is existing technology, and this application does not specifically limit it, nor does it provide corresponding drawings. Examples of existing position detection units are as follows:

[0111] Example 1: Each positioning component's drive motor (such as a stepper motor / servo motor) has a built-in rotary encoder, which detects the number of motor rotations and the lead screw 314. The radial displacement of the contact part 311 is indirectly calculated. By reading the encoder pulse count, the controller can accurately obtain the real-time radial position of the contact part 311 and determine whether it is within the preset positioning range.

[0112] Example 2: Install a linear displacement sensor (such as a magnetostrictive sensor, an inductive displacement sensor, or a grating ruler) on the contact part 311 or the double-threaded connecting sleeve to directly measure the radial expansion and contraction displacement of the contact part 311.

[0113] S33. If the contact part 311 is already in the working position, start pressure detection and adjust the position of the contact part 311 until the detection value of the pressure sensor 313 falls within the working threshold range.

[0114] That is, the working threshold range satisfies: , The controller reads the detected pressure values ​​from each pressure sensor 313.

[0115] S34. Record the position coordinates of each contact part 311 as follows:

[0116] ,

[0117] In the formula: This indicates the spatial location of the first contact part 311; This indicates the spatial location of the second contact part 311; This indicates the spatial location of the third contact part 311.

[0118] The longitudinal movement error compensation table for worktable 1 in step S5 specifically includes:

[0119] S51. The deviation of worktable 1 along the Y-axis and parallel to the XOZ plane is:

[0120] ;

[0121] ;

[0122] In the formula, The total number of experiments, For the first This experiment; This indicates the offset along the X-axis at the Y-axis position; This indicates the offset along the Z-axis at the Y-axis position;

[0123] S52. Measure the position points of each Y-axis of worktable 1 to obtain the longitudinal movement error compensation table of worktable 1.

[0124] A specific test method example involves placing the laser interferometer along the X and Z axes on the reference plane of worktable 1, calibrating the measurement optical path to its optimal state, and controlling worktable 1 to move along the Y axis from the starting position (y=0mm) to the maximum travel position (y=3000mm) in preset steps (e.g., 30mm). After reaching each target position, the current Y coordinate and the corresponding X-axis error are recorded. Z-axis error ; Among them, the total number of experiments Next, multiple sets of repeated experimental data were obtained and the average value was calculated to ensure accuracy. The resulting error compensation representation is as follows:

[0125]

[0126] In step S5, the movement of the contact part 311 is controlled according to the correspondence between the Y-axis coordinate value or coordinate difference and the longitudinal movement error compensation table of the worktable 1. Specifically, this includes:

[0127] The amount of extension / retraction of the contact portion 311 The calculation formula is:

[0128] ;

[0129] In the formula, Indicates the first Contact part 311, This indicates the outer radius of the boring bar 21 used for machining the first hole. This indicates the outer radius of the boring bar 21 used for machining the second hole. This represents the coordinate difference between the first hole and the second hole along the X-axis of worktable 1. This represents the coordinate difference between the first hole and the second hole along the X-axis of worktable 1. Indicates the first The initial extension / retraction direction angle of the contact portion 311 during the machining of the first hole.

[0130] according to The positive and negative values, if If the value is greater than 0, then the drive mechanism 312 controls the contact portion 311 to extend towards the rotation axis of the boring bar 21; if If the value is less than 0, the drive mechanism 312 controls the contact part 311 to retract in a direction away from the rotation axis of the boring bar 21.

[0131] Examples of this invention are as follows:

[0132] Reference Figures 4 to 6 As shown, The spatial position point where the boring bar 21 used to machine the first hole contacts the first contact part 311; The spatial position point where the boring bar 21 used to machine the first hole contacts the second contact part 311; The spatial position point where the boring bar 21 used to machine the first hole contacts the third contact part 311; The spatial position point where the boring bar 21 used to machine the first hole contacts the first contact part 311; The spatial position point where the boring bar 21 used for machining the second hole contacts the second contact part 311; The spatial position point where the boring bar 21 used to machine the second hole contacts the third contact part 311;

[0133] Figure 4This is a three-dimensional schematic diagram of the processing method based on the intelligent coaxial hole processing device of the present invention, showing the processing of the first hole and the second hole. The first hole and the second hole need to be processed coaxially, and the boring bar 21 used to process the first hole and the boring bar 21 used to process the second hole have the same diameter.

[0134] Figure 5 This is a front view of the machining method based on the coaxial hole intelligent machining device of the present invention, showing the machining of the first hole and the second hole. The first hole and the second hole need to be machined coaxially, and the boring bar 21 used to machine the first hole and the boring bar 21 used to machine the second hole have the same diameter. The black line represents the outline of the boring bar 21 used to machine the first hole, and the red line represents the outline of the boring bar 21 used to machine the first hole.

[0135] Figure 6 This is another front view of the machining method based on the coaxial hole intelligent machining device of the present invention, showing the machining of the first hole and the second hole. The first hole and the second hole need to be machined coaxially, and the diameters of the boring bar 21 used to machine the first hole and the boring bar 21 used to machine the second hole are different. The black line represents the outline of the boring bar 21 used to machine the first hole, the red line represents the outline of the boring bar 21 used to machine the first hole, and the blue line represents the boring bar 21 used to machine the first hole. Because the machining component 2 can slide and feed along the Y-axis direction of the worktable 1, or the machining component 2 can remain stationary and fixed, the component to be machined is driven to slide and feed along the Y-axis direction of the worktable 1 by the drive mounting table. This movement causes the center of the boring bar 21 to shift in the X-axis direction.

[0136] During the machining of the first hole: the three contact parts 311 are distributed at equal angles of 120°, the contact parts... Angle with the X-axis , contact department Angle with the X-axis , contact department Angle with the X-axis Corresponding to: , , ; Set to 100mm, If the offset of worktable 1 is set to 80mm, and it is at Y=0 when machining the first hole, and at Y=2710mm when machining the second hole, then the offset of worktable 1 can be obtained through the error compensation table. mm, mm;

[0137] Among them, the contact part Angle with the X-axis , contact department Angle with the X-axis , contact department Angle with the X-axis The position coordinates of each contact part 311 recorded in step S3 can be used as a reference. Calculations are performed to obtain the results;

[0138] Calculate the displacement of each contact part 311 by substituting it into the above formula:

[0139] (1) For point :

[0140] Then control the contact part It extends approximately 32.51 mm in the direction closer to the axis of rotation of the boring bar 21;

[0141] (2) For point :

[0142] Then control the contact part It extends approximately 23.19 mm in the direction closer to the axis of rotation of the boring bar 21;

[0143] (2) For point :

[0144] Then control the contact part It extends approximately 6.42 mm in the direction closer to the axis of rotation of the boring bar 21;

[0145] Regarding the processing method of Embodiment 2 above:

[0146] A machining method for a coaxial hole intelligent machining device based on large hole spacing includes the following steps:

[0147] S1. Determine the center axis of the first hole to be machined, align the rotation axis of the boring bar 21 with the center axis of the first hole, and adjust the radial distance between the boring tool cutting edge and the rotation axis of the boring bar 21 according to the diameter of the first hole.

[0148] S2. Rough boring of the first hole;

[0149] S3. Drive the contact part 311 of the circular positioning instrument 3 to move and abut against the inner circumferential surface of the first hole, so that the detection values ​​of each pressure sensor 313 are within the preset threshold range.

[0150] S4. Record the position coordinates of the contact part 311 and the detection pressure values ​​of each pressure sensor 313, and then control the contact part 311 to move away from the working motion area of ​​the boring bar 21;

[0151] S5. Boring the first hole to the required accuracy;

[0152] S6. Determine the center axis of the second hole to be machined, align the rotation axis of the boring bar 21 with the center axis of the second hole, and adjust the radial distance between the boring tool cutting edge and the rotation axis of the boring bar 21 according to the diameter of the second hole.

[0153] S7. Rough boring of the second hole;

[0154] S8. Calculate the coordinate values ​​or coordinate differences between the first hole and the second hole in the Y-axis direction of the worktable 1, and control the movement of the contact part 311 according to the correspondence between the Y-axis coordinate values ​​or coordinate differences and the longitudinal movement error compensation table of the worktable 1.

[0155] S9. Adjust the position of the workpiece to be processed so that the detected pressure value of each pressure sensor 313 falls into the same preset threshold range as in step S4, and then control the contact part 311 to move away from the working motion area of ​​the boring bar 21.

[0156] S10. Boring the second hole to the required accuracy.

[0157] Example 2 uses the inner wall of the hole to be processed as the positioning reference, so a rough boring process is added to the processing flow: firstly, the first hole and the second hole are rough bored to form a stable inner circumferential surface positioning reference, and then the reference data is collected by the circular positioning instrument 3 and coaxiality compensation is completed.

[0158] Therefore, in Embodiment 2, the amount of extension / retraction of the contact portion 311 is... The calculation formula is:

[0159] ;

[0160] In the formula, Indicates the first One contact part, This indicates the inner diameter of the first hole after rough boring. This indicates the inner diameter of the second hole after rough boring. This indicates the amount of offset in the X-axis direction of the center of the boring bar 21 caused by the movement of the worktable 1. The movement of the worktable 1 causes the center of the boring bar 21 to shift in the Z-axis direction. Indicates the first The initial extension / retraction direction angle of the contact part during the machining of the first hole.

[0161] This invention discloses an intelligent machining device and method for large-pitch coaxial holes. Addressing the technical challenges of large errors, low precision, and cumbersome operation in existing large-pitch coaxial hole machining processes, this invention achieves high-precision and convenient machining of large-pitch coaxial holes through the scientific design of process steps and the integrated application of core technologies. Specific beneficial effects are as follows:

[0162] 1. This processing method, relying on a specially designed circular positioning instrument 3, achieves theoretical zero error and actual minimal error in the straightness or coaxiality of the two holes, completely solving the problem of insufficient precision caused by error accumulation in existing processing methods, and meeting the high-precision processing requirements of coaxial holes with large hole spacing.

[0163] 2. The core feature of the processing technology of this invention is that for a pair or more coaxial holes on a workpiece, the same machine tool, the same process, the same clamping, and the same set of process parameters are used for processing. There is no need for multiple clamping, tool setting, or adjustment of process parameters. This not only significantly improves the convenience of processing, but also effectively avoids the errors caused by multiple clamping and tool setting, ensuring the consistency and high precision of coaxial hole processing, and keeping the coaxiality error within a very small range.

[0164] 3. Minimize original errors and improve machining datum accuracy: In this machining process, except for a slight straightness error in the movement of the worktable 1, all other original errors are close to zero, which is equivalent to achieving synchronous replication of the two holes. Relying on the extremely small straight movement error of the worktable 1, the positioning accuracy and machining accuracy are further guaranteed, reducing the source of error from the source and providing a reliable guarantee for the high-precision machining of coaxial holes with large hole spacing.

[0165] 4. Achieving precise positioning and flexible adaptation by relying on the circular positioning device 3: One of the core features of this processing technology is the use of a specially designed circular positioning device 3. Based on the geometric principle of "three non-coincident points determine a circle", the circular positioning device 3 uses the boring bar 21 as the positioning reference. By fixing the boring bar 21, it is equivalent to fixing the center of the circle, which can conveniently and accurately determine the center of the coaxial hole system with large hole spacing. It is realized through the pressure sensor 313, the drive mechanism 312 and the control algorithm. It can make three-point contact with the outer peripheral surface of the boring bar 21 or the inner wall of the pre-made hole to be processed through three contact parts 311. The contact pressure of each contact part 311 is controlled and pressure fluctuations are suppressed to ensure the reliability and durability of positioning, while adapting to the processing requirements of different hole diameters.

[0166] 5. Enhanced flexibility and processing consistency based on the standardized design of the three sets of contact parts 311: This processing technology adopts the standardized design and manufacturing of the three sets of contact parts 311 (fixed positioning component 31 and moving positioning component 32). That is, all components of the three sets of components, such as the lead screw 314 mechanism, double threaded connecting sleeve, and contact parts 311, adopt the same design, the same clamping and processing, the same tooling step, and the same installation process. Although there may be slight errors in individual parts, the relative error affecting the position of the hole system after assembly is always zero. At the same time, through each drive mechanism 312, the three contact parts 311 can form positioning circles of different diameters on the same concentric circumference, flexibly adapting to the high-precision processing of hole systems with different hole diameters and different axial distances, greatly improving the versatility and adaptability of the device.

[0167] 6. Effective compensation for the guiding error of the worktable 1 to achieve theoretical zero coaxiality error: This machining process adopts a comprehensive method combining experimentation and mathematical approximation to accurately determine the guiding error of the worktable 1 in the X and Z directions when it moves along the Y-axis. Combined with the compensation algorithm calculated by the displacement of the contact part 311, the error is completely compensated by adjusting the position of the boring bar 21, ensuring that the theoretical coaxiality error of the coaxial hole system is zero, further improving the machining accuracy of large-pitch coaxial holes, and ensuring the operating accuracy and performance of the mechanical system.

[0168] 7. This technical solution can be used to process any coaxially arranged holes in a component structure, regardless of hole diameter, hole spacing, or whether they are conventional short-distance coaxial holes, large-span long-distance coaxial holes, or distributed coaxial holes on long-shaft or ultra-long-shaft components. This technology relies on precise center alignment, adaptive deviation detection, and closed-loop compensation adjustment. It is not limited by workpiece shape, clamping method, or hole arrangement, and has extremely high versatility. It can achieve standardized, high-precision positioning and boring of all coaxial holes, greatly improving the coaxial accuracy and processing consistency of various coaxial holes.

[0169] In the description of the invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention.

[0170] In the description of the invention, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature.

[0171] The above description is merely a preferred embodiment of the invention and is not intended to limit the invention. Various modifications and variations are possible for those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the invention should be included within the scope of protection of the invention.

Claims

1. A smart machining device for coaxial holes with large hole spacing, comprising a CNC boring machine, the CNC boring machine including a worktable and a boring bar, the boring bar being equipped with a boring tool, characterized in that: It also includes a circular positioning device and a controller; The circular positioning instrument includes a fixed group and a movable group. The fixed group is provided with two fixed positioning components, and the movable group is provided with one movable positioning component. The two fixed positioning components and the movable positioning component are arranged non-collinearly. The movable positioning component can be moved along the direction close to or away from the rotation axis of the boring bar. Both the fixed positioning component and the mobile positioning component are respectively equipped with a contact part, a pressure sensor and a driving mechanism; The driving mechanism is used to drive the corresponding contact part to move in a direction close to or away from the rotation axis of the boring bar, and the pressure sensor is used to detect the contact pressure between the contact part and the boring bar or the machining hole; The controller is electrically connected to the pressure sensor and the drive mechanism. The controller is used to read the detection value of the pressure sensor and control the drive mechanism to perform extension and retraction actions according to the detection value.

2. The intelligent machining device for large-pitch coaxial holes according to claim 1, characterized in that: The included angle between the central axes of two adjacent fixed positioning components is 120°, and the included angle between the central axes of adjacent fixed positioning components and mobile positioning components is 120°.

3. The intelligent machining device for coaxial holes with large hole spacing according to claim 1, characterized in that: The circular positioning device further includes a fixed frame and a rotating frame. One end of the rotating frame is hinged to the corner of the fixed frame. The fixed positioning component is fixedly installed on the fixed frame, and the moving positioning component is fixedly installed on the rotating frame.

4. The intelligent machining device for coaxial holes with large hole spacing according to claim 1, characterized in that: Both the fixed positioning component and the mobile positioning component are equipped with lead screws, and the lead screws satisfy the following: In the formula, The lead of the leadscrew is... The diameter of the lead screw is given.

5. A processing method based on the intelligent coaxial hole processing device according to any one of claims 1 to 4, characterized in that, Includes the following steps: S1. Determine the center axis of the first hole to be machined, align the rotation axis of the boring bar with the center axis of the first hole, and adjust the radial distance between the boring tool cutting edge and the rotation axis of the boring bar according to the diameter of the first hole. S2. Drive the contact part of the circular positioning instrument to move and abut against the outer circumferential surface of the boring bar, so that the detection values ​​of each pressure sensor are within the preset threshold range; S3. Record the position coordinates of the contact part and the detected pressure values ​​of each pressure sensor, and then control the contact part to move away from the working motion area of ​​the boring bar; S4. Boring the first hole to the required accuracy; S5. Control the movement of the contact part according to the coordinate values ​​or coordinate difference between the first hole and the second hole in the Y-axis direction of the worktable, and the corresponding relationship of the longitudinal movement error compensation table of the worktable. S6. Adjust the position of the boring bar so that the detected pressure values ​​of each pressure sensor fall into the same preset threshold range as in step S3, and then control the contact part to move away from the working motion area of ​​the boring bar; S7. Boring the second hole to the required accuracy.

6. The processing method according to claim 5, characterized in that, Step S3 includes the following sub-steps: S31. Determine the operating threshold range of the pressure sensor based on the material strength of the boring bar and the contact part. ,in: ； In the formula, δ is the material strength reduction factor, which is used to reduce the material's ultimate pressure value to a safe working reference pressure; This represents the ultimate pressure value, which is the strength limit of the material. This is the allowable deviation of the pressure threshold, used to limit the range of fluctuation of the working pressure. S32. Check if each contact part is in the working position. If it is not in the working position, continue to adjust it to the working position. ； S33. If the contact part is already in the working position, start pressure detection and adjust the position of the contact part until the detection value of the pressure sensor falls within the working threshold range. S34. Record the position coordinates of each contact part, denoted as: ； In the formula: This indicates the spatial location of the first contact point; Indicates the spatial location of the second contact point; This indicates the spatial location of the third contact point.

7. The processing method according to claim 6, characterized in that, The longitudinal movement error compensation table for the worktable in step S5 specifically includes: S51. Record the deviation of the worktable along the Y-axis and parallel to the XOZ plane as: ； ； In the formula, The total number of experiments, For the first This experiment; This indicates the offset along the X-axis at the Y-axis position; This indicates the offset along the Z-axis at the Y-axis position; S52. Measure the position points of each Y-axis of the worktable to obtain the longitudinal movement error compensation table of the worktable.

8. The processing method according to claim 7, characterized in that, In step S5, the amount of extension / retraction of the contact portion is... The calculation formula is: ； In the formula, Indicates the first One contact part, This indicates the outer radius of the boring bar used to machine the first hole. This indicates the outer radius of the boring bar used to machine the second hole. This represents the coordinate difference between the first hole and the second hole along the X-axis of the worktable. This represents the coordinate difference between the first hole and the second hole in the Z-axis direction of the worktable. Indicates the first The initial extension / retraction direction angle of the contact part during the machining of the first hole; according to The positive and negative values, if If the value is greater than 0, the control contact part of the drive mechanism extends towards the direction of rotation of the boring bar; if If the value is less than 0, the control contact part of the drive mechanism retracts in a direction away from the rotation axis of the boring bar.

9. A processing method based on the intelligent coaxial hole processing device according to any one of claims 1 to 4, characterized in that, Includes the following steps: S1. Determine the center axis of the first hole to be machined, align the rotation axis of the boring bar with the center axis of the first hole, and adjust the radial distance between the boring tool cutting edge and the rotation axis of the boring bar according to the diameter of the first hole. S2. Rough boring of the first hole; S3. Drive the contact part of the circular positioning instrument to move and abut against the inner circumferential surface of the first hole, so that the detection values ​​of each pressure sensor are within the preset threshold range. S4. Record the position coordinates of the contact part and the detected pressure values ​​of each pressure sensor, and then control the contact part to move away from the working motion area of ​​the boring bar; S5. Boring the first hole to the required accuracy; S6. Determine the center axis of the second hole to be machined, align the rotation axis of the boring bar with the center axis of the second hole, and adjust the radial distance between the boring tool cutting edge and the rotation axis of the boring bar according to the diameter of the second hole. S7. Rough boring of the second hole; S8. Calculate the coordinate values ​​or coordinate difference between the first hole and the second hole in the Y-axis direction of the worktable, and control the movement of the contact part according to the correspondence between the Y-axis coordinate values ​​or coordinate difference and the longitudinal movement error compensation table of the worktable. S9. Adjust the position of the workpiece to be processed so that the detected pressure values ​​of each pressure sensor fall into the same preset threshold range as in step S4, and then control the contact part to move away from the working motion area of ​​the boring bar. S10. Boring the second hole to the required accuracy.

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