A gantry milling C-axis indexing tooth disc zero alignment assembly method

Abstract

The application provides a gantry milling C-axis indexing gear disc zero position alignment assembly method, and relates to the technical field of machine tool assembly and adjustment, which comprises four steps of pre-assembly, parallelism calibration, zero position deviation detection, and error compensation and solidification. By moving the adjustment timing to the sub-assembly stage, taking the ram reference surface as the global reference, the parallelism of the rotating body axis is first checked by using the table and scraping. Then, under the constraint of parallelism, the distance size difference between the pull claw hole and the reference surface is extracted, and then the position of the upper gear disc is fine-tuned and rigid centering is performed. The application adopts the dimensionality reduction decoupling cooperative adjustment mode of "adjusting inclination first and then adjusting eccentricity", discards the traditional general assembly borrowing position extensive process, eliminates the internal stress caused by forced borrowing position, effectively improves the machine tool joint misplacement and oil leakage pain points, significantly reduces the similar failure rate of the machine tool, and greatly improves the overall assembly quality and assembly efficiency of the numerical control machine tool.

Description

Technical Field

[0001] This application relates to the field of machine tool assembly and adjustment technology, and in particular to an assembly method for zero-position alignment of the C-axis indexing gear plate of a gantry milling machine. Background Technology

[0002] like Figures 1-3 The Z-axis of the gantry milling machine 1 is typically a linear axis through which the slide 3 moves up and down along the guide rail surface of the slide 2. An accessory milling head 4 is mounted on the slide 3, and the direction of rotation of the milling head around the Z-axis is the C-axis direction of the gantry milling machine 1. In a conventional structure, the slide 3 typically uses upper and lower gear discs 11 to control the C-axis indexing. The number of teeth and machining accuracy of the gear discs directly affect the C-axis indexing accuracy. Specifically, the upper gear disc 5, slide 3, C-axis transmission device 6, main sleeve 7, and piston body 8 are fixedly connected, forming a fixed part; while the accessory milling head 4, pull claw 9, rotating body assembly 10, lower gear disc 11, cylinder body 12, and transmission shaft assembly 13 are fixedly connected, forming a moving part. The basic process of C-axis rotation indexing is to use hydraulic control to push the rotating body assembly 10, causing the lower gear plate 11 to disengage from the upper gear plate 5; then start the C-axis transmission device 6 to drive the rotating body assembly 10 to rotate by the corresponding angle; finally, through hydraulic control, push the cylinder body 12 to make the lower gear plate 11 mesh with the upper gear plate 5, thus completing the indexing and positioning.

[0003] Among these processes, the zero-position alignment of the C-axis indexing gear plate is crucial for ensuring the geometric accuracy of the subsequent milling head assembly, directly impacting machine tool machining accuracy, mechanical safety, and the logical judgment of the CNC system. However, in existing technologies, this alignment process is typically performed during the machine tool assembly stage, when checking and adjusting the assembly accuracy of the right-angle milling head. By this time, the upper gear plate has already been installed, fixed, and glued during the previous ram assembly stage. If a deviation is discovered during the zero-position alignment of the gear plate during final assembly, since the upper gear plate cannot be adjusted, the operator can only barely complete the alignment by forcibly adjusting the relative position of the milling head and the rotating body (i.e., "borrowing").

[0004] Due to the aforementioned "borrowing" operation, the mating surfaces of various components generate extremely unreasonable internal stress. Furthermore, this borrowing can easily lead to misalignment of other joints between the milling head and the rotating body, which may ultimately cause serious malfunctions such as mechanical damage and oil leakage at the mating surfaces. According to actual assembly statistics, the failure rate caused by this type of rigid leveling exceeds 90%, and the average assembly rework time loss per machine tool exceeds 48 hours, resulting in poor overall assembly quality and low production efficiency. Summary of the Invention

[0005] To address the issues of misalignment of joints, mechanical damage, oil leakage at mating surfaces, and high equipment failure rates caused by rigid offset alignment during the final assembly stage, this application provides an assembly method for zero-position alignment of the C-axis indexing gear plate of a gantry milling machine.

[0006] The assembly method for zero-position alignment of the C-axis indexing gear plate in a gantry milling machine provided in this application adopts the following technical solution: An assembly method for zero-position alignment of the C-axis indexing gear plate in a gantry milling machine includes the following steps: S1. Pre-assembly: Position and install the upper gear plate on the gear plate mounting surface of the slide block, and keep the upper gear plate in an unfastened state; combine the rotating body assembly with the lower gear plate with the slide block, so that the rotating body assembly is positioned by the meshing of the lower gear plate and the upper gear plate; S2. Parallelism calibration: Using the slide reference surface of the slide as the global positioning reference, the relative perpendicularity between the rotating end face of the rotating body assembly and the slide reference surface is obtained, so as to derive the parallelism between the rotation axis of the rotating body assembly and the slide reference surface; and the toothed disk mounting surface is scraped and intervened according to the derived parallelism until the parallelism meets the first preset accuracy. S3. Zero-position deviation detection: Under the mechanical constraint that the parallelism meets the first preset accuracy, the slide ram reference surface is used as the global positioning reference to extract the distance difference between the axis of the multiple accessory claw mounting holes on the rotating body assembly and the slide ram reference surface. S4. Error Compensation and Fixation: Based on the extracted distance difference, the upper gear plate is driven to move relative to the gear plate mounting surface until the distance difference corresponding to the mounting holes of each accessory claw meets the second preset accuracy. Then, the upper gear plate is rigidly fastened to complete the alignment closed loop.

[0007] Furthermore, in step S2, the step of obtaining the relative perpendicularity involves a parallelism detection system, which includes: A right-angle ruler is positioned against and pressed against the end face of the rotating body to convert the end face orientation of the rotating body assembly into a perpendicularity detection reference. A curved plate, perpendicular to the slide ram reference surface, is fitted tightly to the slide ram reference surface to provide a parallel detection guide path; and When the dial indicator assembly is attached to the bending plate, its probe abuts against the other side of the right-angle ruler that is not in contact with the end face of the rotating body. It is used to continuously output the displacement change when the bending plate slides along the feed direction of the slide block, so as to reflect the relative perpendicularity.

[0008] Furthermore, in step S2, obtaining the data acquisition and calculation closed loop for the relative verticality specifically includes: S21. Along the eight directions where the four corners of the slide feed direction are located, the bending plate is translated sequentially and the dial indicator is used for detection, and the first set of spatial detection data is locked and recorded; S22. After driving the rotating body assembly to rotate around its rotation axis by a preset angle, it is again moved along the eight directions to perform dialing detection, and the second set of spatial detection data is locked and recorded. S23. Extract the first set of spatial detection data and the second set of spatial detection data of the right angle ruler at the same spatial position, and calculate the average value of the two to offset the shape and position processing error of the end face of the rotating body, so as to obtain the final relative perpendicularity.

[0009] Furthermore, in step S2, the specific operation process of scraping and intervening on the mounting surface of the gear disc includes: Disengage the rotating body assembly and the temporary engagement between the upper gear plate and the slide block; Apply red lead evenly to the exposed mounting surface of the toothed disc of the ram; After tightly fitting the special grinding tool to the mounting surface of the toothed disc and performing a rotary grinding action, it is removed to obtain the high-protrusion contact marks of the red lead distribution. Based on the distribution characteristics of the contact marks and the derived parallelism deviation, manual metal scraping is performed on the high point area of ​​the toothed disk mounting surface to remove excess material.

[0010] Furthermore, the scraping intervention is performed repeatedly and the device is reassembled and verified until the toothed disc mounting surface meets the first preset accuracy requirement defined by the following parameters: The contact area between the mounting surface of the gear disc and the mating surface of the special grinding tool is not less than 75% of the total area; When a feeler gauge with a thickness of 0.04 mm is used for insertion testing, the circumferential joint of the mating surface shows physical interference and cannot be inserted; and After completing the scraping intervention and repositioning the rotating body assembly, the parallelism between the rotation axis of the rotating body assembly and the slide reference surface is calculated a second time, and its absolute value is no greater than 0.01mm / 1m.

[0011] Furthermore, in step S3, extracting the distance dimension difference involves a zero-position deviation detection system, which includes: A special test bar is coaxially and interference-fitted into the mounting hole of the accessory pull claw to be tested, which is used to convert the spatial position of the hidden internal hole axis into the external solid busbar; A flat plate, selectively abutting against either the front or side reference surface included in the slide ram reference surface, serves as an extended reference for detecting distance dimension differences; and A dial indicator assembly is attached to the plate, with its probe abutting against the positive or side busbar of the special probe, for outputting the absolute distance change of the special probe relative to the positive or side reference plane.

[0012] Furthermore, the step of extracting the error signal for a single accessory claw mounting hole includes: S31. Constrain the plate to fit tightly against the positive reference plane, control the probe of the dial indicator assembly to abut against the positive generatrix of the special test bar, and extract and lock the first stroke reading; S32. Maintain the relative rigidity of the plate and the dial indicator assembly adsorbed thereon, and transfer the plate as a whole and constrain it to the side reference surface; S33. Control the dial indicator assembly to adaptively fit the side busbar of the special test bar and generate piezoresistive contact, extract and lock the second stroke reading, thereby completing the distance data acquisition of a single hole position in both the front and side dimensions.

[0013] Furthermore, the steps for extracting the distance size difference are as follows: The special inspection bar is inserted into the four accessory pull claw mounting holes in turn; Repeat steps S31 to S33 until all eight sets of stroke readings corresponding to the four accessory claw mounting holes are obtained. The eight sets of travel readings are input into the preset comparison algorithm. Using the slide ram reference surface as the coordinate origin, the relative eccentricity values ​​of the axes of the four accessory claw mounting holes on the two-dimensional detection plane are calculated and output as the distance size difference to the feedback loop.

[0014] Furthermore, in step S4, the error compensation step for driving the upper gear disk to cause relative displacement includes: Based on the direction and deviation guidance provided by the calculated distance difference, the upper gear disk, which is not tightened, is forced to slide smoothly in the plane or rotate around its own axis by an external mechanical thrust. After the relative displacement action is completed, control the lower gear to re-engage rigidly with the upper gear after the position change, and verify the position after fine adjustment by mechanical centering. The displacement fine-tuning action of the upper gear disk and the detection step in step S3 are performed alternately and iteratively until the alignment closed loop is satisfied.

[0015] Furthermore, the final execution node for completing the aforementioned alignment loop requires the following: When the relative values ​​of all the distance size differences are converged to less than 0.01 mm after iterative retesting, it is determined that the current system meets the second preset accuracy. The fastening node action is performed by applying force in a symmetrical and cross-shaped sequence around the circumference. The comprehensive positional tolerance state generated by the upper gear plate is permanently fixed and locked onto the gear plate mounting surface by mechanical screws, thus completing the zero-position pre-alignment process applied to the slide assembly stage.

[0016] In summary, this application includes at least one of the following beneficial technical effects: 1. By moving the zero-position positioning of the gear plate from the machine tool assembly stage to the slide assembly stage, and maintaining the initial free state of the upper gear plate, the alignment action is transformed from a passive hard-adjusting milling head to an active fine-adjusting upper gear plate, thereby achieving coaxial centering without internal stress. This effectively solves the problem of a failure rate of over 90% caused by forced borrowing in the existing technology, such as joint misalignment, mechanical damage, and oil leakage at the mating surface. 2. By introducing a two-stage control logic that first checks the parallelism of the toothed disc mounting surface and then extracts the eccentricity error by measuring the gauge bar to fine-tune the position, the spatial three-dimensional assembly tolerance is orthogonally decoupled, thereby realizing the elimination of the mutual interference between parallelism error and coaxiality error, which significantly improves the geometric accuracy and operational stability of machine tool assembly adjustment. 3. By rotating the rotating body under test by 90° and measuring again when testing the perpendicularity with a dial indicator and taking the average value, the machining error of the end face of the rotating body itself is algebraically canceled in the calculation, thereby realizing a purer and more realistic extraction of the assembly tilt angle and improving the problem that the reading is easily distorted under a single measurement condition. 4. By using a circumferentially symmetrical cross-force application process at the final fastening node, the thread preload stress is evenly distributed around the toothed disc, thereby achieving permanent non-destructive curing with extremely low error (less than 0.01mm) tolerance, effectively solving the problem of warping and deformation failure of the scraped surface caused by unidirectional hard tightening. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the Z-axis and C-axis of a gantry milling machine in the background technology; Figure 2 This is a schematic diagram of the meshing and positioning of the upper and lower gear disks in the background art; Figure 3 This is a schematic diagram of the indexing rotation of the upper and lower gear disks in the background art; Figure 4 This is a schematic diagram illustrating how a right-angle ruler and dial indicator are used to detect the parallelism between the axis of the rotating body and the reference surface of the slide block in an embodiment of this application. Figure 5 This is another schematic diagram illustrating the use of a right-angle ruler and dial indicator to detect the parallelism between the axis of the rotating body and the reference surface of the slide block in this embodiment of the application; Figure 6 This is a schematic diagram of an embodiment of this application where the mounting surface of the upper gear disc is scraped with a special grinding tool; Figure 7 This is a schematic diagram illustrating the use of a special inspection bar to detect the difference in distance between the mounting hole of the accessory pull claw and the reference surface of the slide block, according to an embodiment of this application. Figure 8 This is another schematic diagram illustrating the use of a special probe to detect the difference in distance between the mounting hole of the accessory pull claw and the reference surface of the slide block, according to an embodiment of this application. Figure 9 This is a schematic diagram illustrating the principle of using a test bar to detect the position of the upper gear plate in an embodiment of this application.

[0019] Figure label: 1. Gantry milling machine; 2. Slide; 3. Ram; 4. Attachment milling head; 5. Upper gear plate; 6. C-axis transmission device; 7. Spindle sleeve; 8. Piston body; 9. Connecting claw; 10. Rotating body assembly; 11. Lower gear plate; 12. Hydraulic cylinder body; 13. Transmission shaft assembly; 14. Gear plate mounting surface; 15. Right angle ruler; 16. Rotating body end face; 17. Bending plate; 18. Ram reference surface; 19. Dial indicator assembly; 20. Special grinding tool; 21. Attachment connecting claw mounting hole; 22. Special inspection bar; 23. Plate. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0021] Reference Figures 4-9 This application discloses an assembly method for zero-position alignment of the C-axis indexing gear plate in a gantry milling machine, which includes the following steps: S1. Pre-assembly: Position and install the upper gear plate 5 on the gear plate mounting surface 14 of the slide ram 3, and keep the upper gear plate 5 in an unfastened state; combine the rotating body assembly 10 with the slide ram 3, so that the rotating body assembly 10 is positioned by meshing with the upper gear plate 5 through the lower gear plate 11.

[0022] S2. Parallelism calibration: Using the slide reference surface 18 of the slide 3 as the global positioning reference, the relative perpendicularity between the rotating end face 16 of the rotating body assembly 10 and the slide reference surface 18 is obtained to deduce the parallelism between the rotation axis of the rotating body assembly 10 and the slide reference surface 18; and the toothed disk mounting surface 14 is scraped and intervened according to the derived parallelism until the parallelism meets the first preset accuracy.

[0023] S3. Zero-position deviation detection: Under the mechanical constraint that the parallelism meets the first preset accuracy, the distance difference between the axis of the multiple accessory claw mounting holes 21 on the rotating body assembly 10 and the slide reference surface 18 is extracted, using the slide reference surface 18 as the global positioning reference.

[0024] S4. Error Compensation and Fixation: Based on the extracted distance difference, drive the upper gear 5 to move relative to the gear mounting surface 14 until the distance difference corresponding to the mounting holes 21 of each accessory claw meets the second preset accuracy. Then, perform rigid fastening on the upper gear 5 to complete the alignment closed loop.

[0025] Therefore, when aligning the C-axis of the gantry milling machine, the slide block 3 is first smoothly placed into the assembly pit with its gear plate mounting surface 14 facing upwards. At this time, the upper gear plate 5 is in a "free" and adjustable state. Subsequently, the assembly method of this application reduces the dimensionality of the alignment three-dimensional space error. Through the two-stage control logic of leveling the tilt angle in step S2 and compensating for eccentricity in step S4, the traditional one-time forced borrowing mode is avoided. In this way, through the extraction of various detection data and the feedback loop of manual scraping / fine-tuning, the stress-free pure geometric coaxial centering of the parts is achieved from the source, effectively solving the pain points of high machine tool failure rate and long assembly time in the prior art.

[0026] To achieve dimensionality reduction adjustment, in some embodiments, the step of obtaining relative perpendicularity in step S2 involves a parallelism detection system, referring to... Figure 4 and Figure 5 The parallelism detection system includes a right-angle ruler 15, a curved plate 17, and a dial indicator assembly 19. The right-angle ruler 15 is positioned and pressed against the end face 16 of the rotating body, converting the end face orientation of the rotating body assembly 10 into a perpendicularity detection reference. The curved plate 17 is pressed against the slide reference surface 18 in a direction perpendicular to it, providing a parallelism detection guide path. When the dial indicator assembly 19 is attached to the curved plate 17, its probe abuts against the side of the right-angle ruler 15 that is not in contact with the end face 16 of the rotating body, thus continuously outputting the displacement change as the curved plate 17 slides along the feed direction (i.e., the Z-axis direction) of the slide 3. Therefore, the hidden axis parallelism error is visually converted into a visible end face runout displacement using this specialized tooling.

[0027] Specifically, to ensure data reliability, the data acquisition and calculation closed loop for relative verticality in step S2 includes the following execution process: S21. Along the eight directions where the four corners of the slide block 3 are located, sequentially translate the bending plate 17 and perform dial gauge detection, lock and record the first set of spatial detection data; S22. After driving the rotating body assembly 10 to rotate around its rotation axis by a preset angle (exemplarily, it can rotate 90°), it translates again along the eight directions to detect and lock the second set of spatial detection data; S23. Extract the first set of spatial detection data and the second set of spatial detection data at the same spatial position of the right angle ruler 15, and calculate the average value of the two to offset the shape and position machining error of the end face 16 of the rotating body, and obtain the final relative perpendicularity.

[0028] It is worth noting that simple manual dialing can easily introduce the runout error of the machining end face of the rotating component 10 itself. By using the calculation rule of taking the average value after orthogonal angle rotation, the form and position error of the component itself can be cleverly eliminated, and the assembly tilt angle can be truly reflected.

[0029] Furthermore, after calculating the parallelism deviation, the specific operation process of scraping and intervening on the gear plate mounting surface 14 in step S2 includes: Disengage the rotating body assembly 10 and the upper gear plate 5 from the temporary assembly engagement with the slide block 3 and lift them out; Red lead is evenly coated on the exposed toothed plate mounting surface 14 of the bare slide ram 3; After tightly fitting the special grinding tool 20 to the toothed disc mounting surface 14 and performing a rotary grinding action, remove it to obtain high-protrusion contact marks of red lead distribution, such as... Figure 6 As shown; Finally, based on the distribution of contact marks and the deduced parallelism deviation, manual metal scraping was performed on the high point area of ​​the toothed disk mounting surface 14 to remove excess material.

[0030] In other embodiments, in order to establish an objective acceptance standard for subjective manual scraping, the scraping intervention is repeatedly performed and reinstalled for verification until the toothed disk mounting surface 14 meets a first preset accuracy requirement defined by the following parameters: The contact area between the toothed disc mounting surface 14 and the special grinding tool 20 is not less than 75% of the total area; When a feeler gauge with a thickness of 0.04 mm is used for insertion testing, the circumferential joint of the mating surface shows physical interference and cannot be inserted. Furthermore, the absolute value of the parallelism between the rotation axis of the rotating body assembly 10 and the slide reference surface 18 is no greater than 0.01mm / 1m.

[0031] It is important to emphasize here that only when the parallelism accuracy (tilt error) is completely converged will the subsequent two-dimensional zero-position deviation measurement have mathematical and geometric meaning. Otherwise, the needle runout of the dial indicator component 19 will be mixed with the spatial tilt angle, resulting in adjustment distortion.

[0032] After parallelism calibration is completed, in some embodiments, the process proceeds to step S3, which involves extracting the distance dimension difference using a zero-position deviation detection system. (Refer to...) Figure 7 , Figure 8 and Figure 9 The zero-point deviation detection system includes: a dedicated probe 22 coaxially inserted into the mounting hole 21 of the accessory pull claw to be tested; a plate 23 selectively attached to the positive or side reference surface of the slide ram 3; and a dial indicator assembly 19 adsorbed on the plate 23. By inserting the dedicated probe 22 into the mounting hole 21 of the accessory pull claw, the concealed internal hole is replaced by a physical busbar, which facilitates the physical probe of the dial indicator assembly 19 to capture the target.

[0033] Therefore, the specific closed-loop action for extracting the error signal for a single accessory claw mounting hole 21 is as follows: S31. The constraint plate 23 is tightly fitted with the positive reference surface of the slide ram reference surface 18, and the probe of the dial indicator assembly 19 is brought into contact with the positive generatrix of the special test bar 22 to extract and lock the first stroke reading, such as... Figure 7 As shown.

[0034] S32. Maintaining the relative rigidity of the plate 23 and the dial indicator assembly 19 adsorbed thereon, transfer the plate 23 as a whole and constrain it to the side reference surface of the slide ram reference surface 18, as follows. Figure 8 As shown; in specific operation, the dial indicator assembly 19 can be strongly magnetically locked onto the plate 23 by the magnetic base, and the flexible clamping fixture can be used to avoid slight deformation of the indicator frame during the transfer process, so as to ensure that the reference system remains unchanged during cross-reference transfer.

[0035] S33. Control the probe direction of the dial indicator assembly 19 to adaptively fit the side busbar of the special probe 22 and generate piezoresistive contact, extract and lock the second stroke reading.

[0036] Subsequently, the special probe 22 is inserted sequentially into the four accessory claw mounting holes 21, repeating this process until a total of eight sets of travel readings are obtained. Next, the eight sets of travel readings are input into a preset comparison algorithm, using the slide ram reference plane 18 as the coordinate origin, to calculate the relative eccentricity value and output it as the distance dimension difference. Specifically, the comparison algorithm is based on vector difference calculations in a geometric coordinate system, visually mapping the deviation vector of the hole center on the XY plane through the algebraic difference between the front and side readings.

[0037] Entering the error compensation stage in step S4, based on the direction and deviation guidance provided by the calculated distance difference, an external mechanical thrust is applied to force the upper gear 5, which is in a loose state, to perform a smooth sliding or rotational fine-tuning action in the plane. For example, a copper rod can be used to lightly tap or a fine-tuning set screw can be configured to achieve smooth thrust control. After adjustment, the lower gear 11 is controlled to re-engage rigidly with the upper gear 5 for centering verification; fine-tuning and detection are performed alternately and iteratively until the relative values ​​of all distance differences converge to less than 0.01 mm, at which point the current system is determined to meet the second preset accuracy.

[0038] Finally, the fastening action is performed by tightening the machine screws in a symmetrical, cross-force sequence around the circumference. It should be noted that the symmetrical, cross-force application is to ensure that the screw preload is evenly distributed around the gear plate, preventing uneven warping and deformation of the originally scraped high-precision surface due to unilateral force, thereby permanently fixing the overall positional tolerance to the gear plate mounting surface 14.

[0039] The implementation principle of the assembly method for zero-position alignment of the C-axis indexing gear plate of a gantry milling machine according to an embodiment of this application is as follows: The assembly method of this application adopts the core engineering principle of "dimensional upgrading detection and decoupling dimensional reduction adjustment". First, assembly preparation is carried out. During the assembly stage of slide 3, the upper gear plate 5 is set to an unsecured free state and connected to the lower gear plate 11 to simulate the meshing constraint of the final assembly. Then, the parallelism calibration loop (first dimensional reduction stage) is entered. Using the slide ram reference surface 18 as the absolute reference, the invisible axis tilt is converted into the horizontal runout displacement of the end face with the help of the right angle ruler 15, the bending plate 17 and the dial indicator assembly 19. When collecting data, the rotation and averaging algorithm is introduced to eliminate the end face's own machining error. The calculated tilt deviation is combined with the red lead smear mark to guide the manual scraping of the gear plate mounting surface 14 with a special grinding tool 20. The inspection is repeated until the tilt angle parallelism converges to ≤0.01mm / m.

[0040] After eliminating the physical interference of spatial tilt, the zero-position eccentricity calibration loop (second dimensionality reduction stage) is entered. Within the controlled absolute two-dimensional plane, the coordinate data of the four holes are extracted by transferring the plate 23 and probing the front and side generatrices of the special probe 22, and the precise eccentricity vector is calculated. Based on the deviation data, an external force is manually applied to translate or rotate the free upper gear disk 5, and the mechanism correction is verified by repeated engagement of the gear disk. Finally, when all readings approach zero (<0.01mm), a uniform symmetrical torque is used to lock the upper gear disk 5, completing the stress-free, smooth transition closed loop from the free state adjustment to the high-precision constrained state solidification.

[0041] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An assembly method for zero-position alignment of the C-axis indexing gear plate in a gantry milling machine, characterized in that, Includes the following steps: S1. Pre-assembly: Position and install the upper gear plate on the gear plate mounting surface of the slide block, and keep the upper gear plate in an unfastened state; combine the rotating body assembly with the lower gear plate with the slide block, so that the rotating body assembly is positioned by the meshing of the lower gear plate and the upper gear plate; S2. Parallelism calibration: Using the slide reference surface of the slide as the global positioning reference, the relative perpendicularity between the rotating end face of the rotating body assembly and the slide reference surface is obtained, so as to derive the parallelism between the rotation axis of the rotating body assembly and the slide reference surface; and the toothed disk mounting surface is scraped and intervened according to the derived parallelism until the parallelism meets the first preset accuracy. S3. Zero-position deviation detection: Under the mechanical constraint that the parallelism meets the first preset accuracy, the slide ram reference surface is used as the global positioning reference to extract the distance difference between the axis of the multiple accessory claw mounting holes on the rotating body assembly and the slide ram reference surface. S4. Error Compensation and Fixation: Based on the extracted distance difference, the upper gear plate is driven to move relative to the gear plate mounting surface until the distance difference corresponding to the mounting holes of each accessory claw meets the second preset accuracy. Then, the upper gear plate is rigidly fastened to complete the alignment closed loop.

2. The assembly method for zero-position alignment of the C-axis indexing gear plate in a gantry milling machine according to claim 1, characterized in that, In step S2, obtaining the relative perpendicularity involves a parallelism detection system, which includes: A right-angle ruler is positioned against and pressed against the end face of the rotating body to convert the end face orientation of the rotating body assembly into a perpendicularity detection reference. A curved plate, perpendicular to the slide ram reference surface, is fitted tightly to the slide ram reference surface to provide a parallel detection guide path; and When the dial indicator assembly is attached to the bending plate, its probe abuts against the other side of the right-angle ruler that is not in contact with the end face of the rotating body. It is used to continuously output the displacement change when the bending plate slides along the feed direction of the slide block, so as to reflect the relative perpendicularity.

3. The assembly method for zero-position alignment of the C-axis indexing gear plate in a gantry milling machine according to claim 2, characterized in that, In step S2, obtaining the data acquisition and calculation closed loop for the relative verticality specifically includes: S21. Along the eight directions where the four corners of the slide feed direction are located, the bending plate is translated sequentially and the dial indicator is used for detection, and the first set of spatial detection data is locked and recorded; S22. After driving the rotating body assembly to rotate around its rotation axis by a preset angle, it is again moved along the eight directions to perform dialing detection, and the second set of spatial detection data is locked and recorded. S23. Extract the first set of spatial detection data and the second set of spatial detection data of the right angle ruler at the same spatial position, and calculate the average value of the two to offset the shape and position processing error of the end face of the rotating body, so as to obtain the final relative perpendicularity.

4. The assembly method for zero-position alignment of the C-axis indexing gear plate in a gantry milling machine according to claim 1, characterized in that, In step S2, the specific operation process of scraping and intervening on the mounting surface of the gear disc includes: Disengage the rotating body assembly and the temporary engagement between the upper gear plate and the slide block; Apply red lead evenly to the exposed mounting surface of the toothed disc of the ram; After tightly fitting the special grinding tool to the mounting surface of the toothed disc and performing a rotary grinding action, it is removed to obtain the high-protrusion contact marks of the red lead distribution. Based on the distribution characteristics of the contact marks and the derived parallelism deviation, manual metal scraping is performed on the high point area of ​​the toothed disk mounting surface to remove excess material.

5. The assembly method for zero-position alignment of the C-axis indexing gear plate in a gantry milling machine according to claim 4, characterized in that, The scraping intervention is performed repeatedly and the device is reassembled and verified until the toothed disc mounting surface meets the first preset accuracy requirement defined by the following parameters: The contact area between the mounting surface of the gear disc and the mating surface of the special grinding tool is not less than 75% of the total area; When a feeler gauge with a thickness of 0.04 mm is used for insertion testing, the circumferential joint of the mating surface shows physical interference and cannot be inserted; and After completing the scraping intervention and repositioning the rotating body assembly, the parallelism between the rotation axis of the rotating body assembly and the slide reference surface is calculated a second time, and its absolute value is no greater than 0.01mm / 1m.

6. The assembly method for zero-position alignment of the C-axis indexing gear plate in a gantry milling machine according to claim 1, characterized in that, In step S3, extracting the distance dimension difference involves a zero-position deviation detection system, which includes: A special test bar is coaxially and interference-fitted into the mounting hole of the accessory pull claw to be tested, which is used to convert the spatial position of the hidden internal hole axis into the external solid busbar; A flat plate, selectively abutting against either the front or side reference surface included in the slide ram reference surface, serves as an extended reference for detecting distance dimension differences; and When the dial indicator assembly is attached to the plate, its probe abuts against the positive or side busbar of the special test bar, and is used to output the absolute distance change of the special test bar relative to the positive or side reference surface.

7. The assembly method for zero-position alignment of the C-axis indexing gear plate in a gantry milling machine according to claim 6, characterized in that, The steps for extracting error signals for a single accessory claw mounting hole include: S31. Constrain the plate to fit tightly against the positive reference plane, control the probe of the dial indicator assembly to abut against the positive generatrix of the special test bar, and extract and lock the first stroke reading; S32. Maintain the relative rigidity of the plate and the dial indicator assembly adsorbed thereon, and transfer the plate as a whole and constrain it to the side reference surface; S33. Control the dial indicator assembly to adaptively fit the side busbar of the special test bar and generate piezoresistive contact, extract and lock the second stroke reading, thereby completing the distance data acquisition of a single hole position in both the front and side dimensions.

8. The assembly method for zero-position alignment of the C-axis indexing gear plate in a gantry milling machine according to claim 7, characterized in that, The steps for extracting the distance size difference are as follows: The special inspection bar is inserted into the four accessory pull claw mounting holes in turn; Repeat steps S31 to S33 until all eight sets of stroke readings corresponding to the four accessory claw mounting holes are obtained. The eight sets of travel readings are input into the preset comparison algorithm. Using the slide ram reference surface as the coordinate origin, the relative eccentricity values ​​of the axes of the four accessory claw mounting holes on the two-dimensional detection plane are calculated and output as the distance size difference to the feedback loop.

9. The assembly method for zero-position alignment of the C-axis indexing gear plate in a gantry milling machine according to claim 1, characterized in that, In step S4, the error compensation step for driving the upper gear disk to cause relative displacement includes: Based on the direction and deviation guidance provided by the calculated distance difference, the upper gear disk, which is not tightened, is forced to slide smoothly in the plane or rotate around its own axis by an external mechanical thrust. After the relative displacement action is completed, control the lower gear to re-engage rigidly with the upper gear after the position change, and verify the position after fine adjustment by mechanical centering. The displacement fine-tuning action of the upper gear disk and the detection step in step S3 are performed alternately and iteratively until the alignment closed loop is satisfied.

10. The assembly method for zero-position alignment of the C-axis indexing gear plate in a gantry milling machine according to claim 9, characterized in that, The final execution node requirement for completing the alignment loop is as follows: When the relative values ​​of all the distance size differences are converged to less than 0.01 mm after iterative retesting, it is determined that the current system meets the second preset accuracy. The fastening node action is performed by applying force in a symmetrical and cross-shaped sequence around the circumference. The comprehensive positional tolerance state generated by the upper gear plate is permanently fixed and locked onto the gear plate mounting surface by mechanical screws, thus completing the zero-position pre-alignment process applied to the slide assembly stage.

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