A lightweight processing device for a trailer axle head

Abstract

The application discloses a trailer axle head lightweight processing device and belongs to the technical field of axle head processing devices. The device comprises a controller, a horizontal machine table, a coordinate calibration box, a C-shaped coplanar detection unit, a synchronous turning unit and a full-profile allowance verification control unit. The horizontal machine table is in an L-shaped structure. A power main shaft is installed on the vertical surface of the horizontal machine table. A chuck clamp is fixed to the rotating end of the power main shaft. The coordinate calibration box is in a hollow structure towards one end of the power main shaft. The coordinate calibration box comprises a calibration pedestal which is integrally made of three adjacent vertical surfaces. An outer cover is fixed to the outside of the calibration pedestal. The trailer axle head lightweight processing device can complete the axle head finish machining without reserving excessive allowance and is more lightweight. Moreover, the device can protect the machining tool and directly eliminate the error or clamping slight deviation of the axle head blank during turning.

Description

Technical Field

[0001] This invention specifically relates to a lightweight processing device for trailer axle heads, belonging to the technical field of axle head processing devices. Background Technology

[0002] Axle heads are key components in mechanical equipment, widely used in transmission and support systems of forklifts, trailers, concrete mixers, and automobiles. Their core functions include connecting rotating parts, supporting operating loads, and ensuring equipment stability. As a type of metal shaft, trailer axle heads often require a lathe for machining. The spindle drives the axle head to rotate, and a cutting tool is used to machine the surface. For example, Chinese Patent Publication No. CN121535231A discloses a lightweight machining device for trailer axle heads, including a chuck rotatably mounted on the left side of the inner wall of a base. Three sets of moving blocks are slidably mounted on the inner wall of the chuck. Jaws are fixedly mounted on the right side of each moving block. Workpieces are clamped between the multiple sets of jaws. When the clamping plate is fully in contact with the workpiece, bolts rotate and abut against a sealing plate, thereby restricting the movement of the sealing plate and limiting... The deformation of the clamping plate allows it to generate a rigid clamping force on the workpiece with a larger contact area, preventing rigid damage to the workpiece by the chuck during clamping. This structure solves the clamping problem of axle head blanks. However, in the current production of trailer axle heads, inspection is carried out after production is completed. Once the inspection fails, the axle head must be scrapped. Especially when the fixture is eccentric or the axle head blank itself is defective, multiple defective products will be generated, wasting processing resources. Moreover, since the entire finishing process is in a blind machining state, a certain turning allowance needs to be increased to avoid scrapping the final machined axle head. Finishing requires tool feed for the same machining area to achieve the required inner and outer diameters. The production turning workload is large, and since the actual inner and outer diameters of the axle head blank cannot be monitored, the turning process is prone to tool breakage due to excessive thickness. Summary of the Invention

[0003] To address the aforementioned issues, this invention proposes a lightweight machining device for trailer axle heads, which eliminates the need for excessive allowances and achieves more lightweight precision machining of the axle heads. Furthermore, it protects the machining tools and can directly eliminate errors or minor clamping deviations during the production and forming of the axle head blanks during turning.

[0004] The lightweight processing device for trailer axle heads of the present invention includes: Controller for overall machine control; A horizontal machine tool, which has an L-shaped structure, has a power spindle mounted on its vertical surface. A chuck fixture is fixed to the rotating end of the power spindle. The chuck fixture can clamp and lock the shaft head blank, and the power spindle can drive the shaft head blank to rotate, thereby realizing the inspection and processing of it. The coordinate calibration box has a hollow structure at the end facing the power spindle. The coordinate calibration box includes a calibration platform, which is integrally formed from three adjacent vertical surfaces. An outer cover is fixed to the outside of the calibration platform. The C-shaped coplanar detection unit includes a first calibration seat slidably disposed on the upper part of a calibration platform, the first calibration seat being fixed to the calibration platform by bolts; a first closed-loop stepping platform is fixed on the first calibration seat; a hollow frame is fixed to the slider of the first closed-loop stepping platform by a clamp; the frame is hollow inside, and an inner hole laser sensor and an outer circle laser sensor are respectively fixed to the upper and lower parts of the frame away from the hollow end; the inner hole laser sensor and the outer circle laser sensor adopt a time-division multiplexing anti-interference method, both of which use 650nm line lasers, and the inner hole laser sensor and the outer circle laser sensor emit lasers alternately. The laser emits at a frequency of 10kHz. The receivers of the inner hole laser sensor and the outer circle laser sensor receive the data synchronously. Data is collected only when the corresponding sensor emits laser light. 1000 points can be collected in one revolution of the axle head blank, which fully meets the detection accuracy requirements. A 45° total reflection prism is set in the hollow end of the frame, facing the inner hole laser sensor and the outer circle laser sensor. The angle of the two sets of 45° total reflection prisms is adjusted by a laser interferometer so that the scanning planes of the two laser beams of the inner hole laser sensor and the outer circle laser sensor are completely coplanar. After the 45° total reflection prism deflects the laser beams of the inner hole laser sensor and the outer circle laser sensor by 90°, it vertically scans the inner hole and outer circle of the axle head. The C-shaped coplanar detection unit uses a hollow frame as a carrier, with the opening facing the shaft blank. The opening width is 10mm larger than the maximum outer diameter of the blank. The inner hole laser sensor and the outer circle laser sensor are installed on the upper and lower sides of the frame end. The scanning frequency of the inner hole laser sensor and the outer circle laser sensor is 100kHz, and the measurement accuracy is ±0.0005mm. The scanning planes of the inner hole laser sensor and the outer circle laser sensor are strictly coplanar. During scanning, the power spindle drives the shaft blank to rotate one revolution, and the inner hole laser sensor and the outer circle laser sensor synchronously collect the inner diameter and outer diameter data of the shaft blank at each angle within a 360° range. A synchronous turning unit is located directly below the first calibration base; the detection point of the C-shaped coplanar detection unit and the machining point of the synchronous turning unit are on the same vertical line, and the vertical line is on the plane formed by the axis of the power spindle and the z-axis; A full contour margin verification control unit is integrated inside the controller.

[0005] The lightweight machining device for trailer axle heads of this invention pre-calibrates the coordinates of the C-shaped coplanar detection unit and the synchronous turning unit through a coordinate calibration box, ensuring that the detection end of the C-shaped coplanar detection unit and the machining end of the synchronous turning unit are on the same vertical line. By adjusting the position of the coordinate calibration box on the horizontal machine tool, an integrated structure of the horizontal machine tool and the coordinate calibration box is achieved, rigidly locking the coordinate system of the separate C-shaped coplanar detection unit, the synchronous turning unit, and the rotation center of the power spindle. This achieves pre-coaxiality, eliminating the need for subsequent coordinate unification calculations. The scanned original contour data is directly unified with the power spindle to the reference coordinate system. When the full contour allowance verification control unit calculates, it ensures accurate and error-free calculation of the machining allowance across the entire area and automatic determination of the eccentricity type. During operation, the axle head blank of the radially forged seamless steel pipe is clamped on a high-precision spindle chuck fixture. The C-shaped coplanar detection unit moves to the entire area or key section position of the axle head blank, and the power spindle drives the axle head blank to rotate one revolution, completing the circumferential synchronous scanning of the complete inner and outer contours of that area. The first closed-loop stepping platform steps back... The process involves retracting the spindle blank and performing a high-speed rotational scan to obtain the full contour data of the inner and outer parts of the blank. The controller calculates the feasible machining area through the full contour allowance verification control unit and verifies whether the center of the drive spindle is within this area. After verification, the synchronous turning unit feeds along the Z-axis. The internal turning tool and the external turning tool simultaneously turn the inner and outer circles concentric with the spindle at a fixed radius and feed. After machining, a quality report containing the wall thickness distribution is automatically generated. The machined inner hole and outer circle are both circles centered on the center of the drive spindle, and they are absolutely concentric, with zero wall thickness difference at all angles of the same circumference. By strictly controlling the eccentricity and roundness error of the radially forged spindle blank, it can be ensured that all spindle blanks can pass the verification. Unqualified blanks can be rejected in advance to avoid wasting machining time. The machined axle head can achieve zero coaxiality error and zero wall thickness difference with the parameters specified in the drawing. The machining process is simple, and the tool only needs to feed at a fixed radius without any real-time adjustment. The quality is the most stable, and the product quality of all qualified spindle blanks is completely consistent.

[0006] Furthermore, the full contour allowance verification control unit calculates the machining allowance for the outer circle and inner hole of any candidate machining center at any angle. When the allowance for the outer circle and inner hole at all angles is greater than or equal to 0, the candidate machining center is a feasible machining area. Instead of repeatedly adjusting the position of the shaft head blank within the feasible machining area, the blank's qualification is directly verified. The feasible machining area is the set of all machining center positions capable of machining inner and outer circles that meet the drawing requirements. If the power spindle center is within this area, it indicates sufficient machining allowance at all angles, allowing for the removal of all errors in the blank and obtaining a shaft head with concentric inner and outer circles. If the power spindle center is not within this area, it indicates insufficient machining allowance at at least one angle, making it impossible to machine concentric circles, and the blank is unqualified. When the power spindle center falls into the feasible machining area, the synchronous turning unit feeds according to the inner and outer diameter requirements of the shaft head. If the power spindle is not within the feasible machining area, it is determined that the machining allowance for the outer circle or inner hole at at least one angle is insufficient, failing to meet the machining requirements, triggering an automatic alarm, and the shaft head blank is discarded. The specific calculation is as follows: The full profile margin verification control unit predefines calculation parameters, among which The polar angle (0°-360°) of the shaft head blank cross section corresponds to the angle of rotation of the shaft head blank; The outer diameter of the shaft head blank obtained by scanning is at an angle The actual radius at the location (polar coordinates of the outer contour of the shaft head blank); The inner hole of the shaft head blank obtained by scanning is at an angle The actual radius at the location (polar coordinates of the inner contour of the shaft head blank); Coordinates of the candidate machining center (spindle rotation center is fixed at (0,0)); The outer radius of the finished product as required by the drawing (fixed value); The inner diameter of the finished product as required by the drawing (fixed value); The machining allowance for the outer ring is calculated as follows: ; For the outer circle of the blank at the angle The original radius at that point, which is the distance from the outer surface of the blank to the geometric center of the outer circle of the blank; for From the candidate machining center to the outer diameter of the shaft head blank The actual distance of the point , On the outer circle of the shaft head blank The coordinates of the point in the rectangular coordinate system (with the geometric center of the outer circle of the shaft head blank as the origin). outer circle of blank The effective radius of the point relative to the candidate machining center, minus To obtain the thickness of metal that needs to be machined away at that angle, i.e., the machining allowance for the outer diameter; when "Time" indicates the angle. At this point, the outer diameter of the blank has sufficient allowance to be machined to the finished radius. If it is negative, it means that the outer diameter of the blank at that position is insufficient and the required outer diameter cannot be machined.

[0007] The machining allowance for the inner circle is calculated as follows: ; For the inner hole of the blank at an angle The original radius at that point is the distance from the inner surface of the shaft head blank to the geometric center of the inner hole of the blank. Candidate machining center to the inner hole of the blank The actual distance between the points; For the inner hole of the shaft head blank The effective radius of the point relative to the candidate machining center; its minus To obtain the thickness of metal that needs to be machined away at this angle, i.e. the machining allowance for the inner hole; when "Time" indicates the angle. At this point, the inner hole of the blank has sufficient allowance to be machined to the finished radius. If it is negative, it means that the outer diameter of the blank at that position is too large and the required inner hole cannot be machined. The difference between calculating the machining allowance for the outer diameter and the inner diameter is that the outer diameter is calculated by subtracting the effective radius from the blank radius and then subtracting the finished radius; the inner hole is calculated by subtracting the blank radius from the effective radius and then subtracting the finished radius. The reason is that the outer diameter is machined from the outside to the inside, while the inner hole is machined from the inside to the outside, and the calculation direction of the allowance is opposite. When calculating the full contour allowance, the control unit can guarantee absolute concentricity: when the center (0,0) of the power spindle is within the feasible machining area, the tool will operate at a fixed radius. and The feed ensures that the machined inner and outer circles are perfectly concentric with the center of the power spindle, achieving zero wall thickness difference, i.e., the finished wall thickness is perfect. (Fixed value) and angle It is irrelevant; theoretically, the wall thickness difference is 0. If the center of the power spindle is not within the feasible machining area, it means that the allowance of the outer circle or inner hole at at least one angle is insufficient, and it is impossible to machine out the standard inner and outer concentric circles. The blank is directly judged as unqualified.

[0008] Furthermore, the full contour allowance verification control unit also includes a defect determination unit. After receiving an alarm signal, the defect determination unit performs defect determination as follows: by comparing the synchronous correlation of the inner and outer circumferential machining allowances, if the overall allowances are symmetrically deviated in the same direction, it is determined to be a fixture clamping axis offset; if the allowances are disordered and independent, it is determined to be a blank manufacturing eccentricity; after classification and identification, only the clamping eccentricity is corrected by three-dimensional micro-alignment of the chuck fixture, and after correction, the full contour allowance verification continues. When it is determined to be a blank manufacturing eccentricity, the blank is directly scrapped.

[0009] The characteristics of clamping eccentricity (man-made installation offset, not inherent to the shaft head blank) are as follows: On the full circumference, the inner and outer allowances shift synchronously and periodically in the same direction. On one side, the outer allowance is generally larger and the inner allowance is also synchronously larger. On the opposite side, the outer allowance is generally smaller and the inner allowance is also synchronously smaller. The defect judgment unit determines that the inner and outer allowances are sinusoidally symmetrically offset across the entire domain, indicating clamping eccentricity. The chuck fixture needs to be fine-tuned or the shaft head blank needs to be readjusted to align the power spindle reference.

[0010] The characteristics of the original eccentricity of the shaft head blank forging body (inherent in the shaft head blank and unrelated to clamping) are as follows: the internal and external distortions of the shaft head blank are independent and unrelated, the outer diameter allowance is sometimes large and sometimes small, the inner diameter allowance is chaotic and has no synchronous pattern, and the two offsets are not linked and are not in the same direction; the defect judgment unit judges that: the allowance is chaotic and has no synchronous symmetry pattern, which determines that the shaft head blank itself is eccentric and there is no problem with clamping.

[0011] Furthermore, the full contour allowance verification control unit also includes a tool feed calculation unit. The tool feed calculation unit sequentially obtains the maximum outer diameter and the minimum inner diameter of the shaft head after scanning one circumference; and calculates the difference between the actual inner and outer diameter parameters calibrated in this area and the inner and outer diameter parameters obtained from the scanning. Finally, the difference is divided by the maximum cutting amount of the synchronous turning unit to determine the number of feeds. When the number of feeds is a decimal, the decimal is discarded, and 1 is added to the number of feeds to obtain the total number of feeds. Finally, the difference is divided by the number of feeds to obtain the feed amount for each feed. The synchronous turning unit performs the turning work according to the total number of feeds and the feed amount for each feed. It first calculates the maximum cutting amount of one circumference of the surface to be machined, then calculates the number of tool feeds based on the maximum cutting amount and the maximum feed amount of the track, and finally distributes the maximum cutting amount evenly across the number of tool feeds.

[0012] Furthermore, the synchronous turning unit is located directly below the first calibration base; the synchronous turning unit includes a second calibration base fixed to the calibration base by bolts, and a second closed-loop stepping platform is fixed on the second calibration base; a tool holder is fixed on the slider of the second closed-loop stepping platform, and two sets of Z-axis electric slides are fixed on the tool holder with vertical offset; an internal boring tool unit and an external turning unit are fixed on the slider of the Z-axis electric slide through a support arm; during operation, the internal boring tool unit and the external turning unit are translated to the inner and outer walls of the shaft head blank by the second closed-loop stepping platform, and then the two sets of Z-axis electric slides on the tool holder drive the internal boring tool unit and the external turning unit to feed the inner and outer walls of the shaft head blank, and the second closed-loop stepping platform slides along the axial direction of the shaft head blank, and the power spindle drives the shaft head blank to rotate circumferentially to complete the turning machining of the inner and outer wall areas of the shaft head blank.

[0013] Furthermore, the first closed-loop stepping platform and the second closed-loop stepping platform include an electric lead screw slide. An optical grating ruler is fixed to the outside of the slide base of the electric lead screw slide. The reading head equipped with the optical grating ruler is fixed to the side of the slider of the electric lead screw slide. The electric lead screw slide can drive the slider to slide linearly along the slide base. During sliding, the slider displacement can be accurately monitored through the cooperation of the optical grating ruler and the reading head.

[0014] Furthermore, a dovetail rail is integrally formed on the horizontal surface of the horizontal machine tool; a positioning rim is fixed to the outside of the dovetail rail; the coordinate calibration box is movably fitted with the dovetail rail and fixed to the positioning rim by bolts; in use, the coordinate calibration box is replaced and installed as a whole according to different axle head models.

[0015] Furthermore, a coaxial laser cladding unit is fixed to the side of the internal boring tool unit. The cladding end of the coaxial laser cladding unit is coplanar with the machining surface of the boring end of the internal boring tool unit. The coaxial laser cladding unit includes a laser cladding head, which adopts an annular powder feeding nozzle. When a defect is detected in the shaft blank itself, it is determined whether the defect location is a critical area. If so, it is scrapped. If not, the area and depth of the defect are determined. If they exceed the set value, it is scrapped. If they do not exceed the set value, the defect location is clad by the coaxial laser cladding unit, and then turned. In addition, the coaxial laser cladding unit is also used for surface reinforcement. When turning to the bearing position and oil seal position, laser cladding is started simultaneously to directly clad a nickel-based tungsten carbide alloy reinforcement layer on the newly turned near-surface. Because the surface after turning has high activity, the bonding strength between the cladding layer and the substrate is greatly improved, and deformation caused by subsequent heat treatment can be avoided.

[0016] Furthermore, the cladding powder is a nickel-based tungsten carbide alloy, and the cladding thickness is adjustable from 0.3 to 0.8 mm.

[0017] Furthermore, the internal boring tool unit and the external turning unit are passive carbide tools held by tool chucks or grinding tools driven by grinding drive equipment. Through the high-speed rotation power of the power spindle, the shaft head blank workpiece is driven to rotate at high speed, and the passive carbide tool performs passive turning on the shaft head blank. When an automatic force grinding tool is used, the power spindle acts as a shaft head blank rotation reversing unit, and the grinding tool actively turns the inner and outer walls of the shaft blank.

[0018] Compared with the prior art, the lightweight machining device for trailer axle heads of the present invention has the following advantages: by performing coplanar scanning of the inner and outer circles of the axle head, the machining allowance of the entire contour of the axle head is determined, eliminating the need to reserve excessive allowance, thus completing the precision machining of the axle head in a lighter manner; and it can calculate the tool feed rate and number of feeds based on the full contour data of the axle head, avoiding tool breakage. During turning, axle head blanks that meet the reserved allowance can be directly machined, directly eliminating errors or slight deviations in the production and forming of the axle head blanks, ensuring that the inner and outer circles of the machined axle head are concentric, and meeting the requirements for inner and outer diameters and wall thickness. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of the lightweight processing device for trailer axle heads according to the present invention.

[0020] Figure 2 This is a schematic diagram of the lightweight processing device for trailer axle heads of the present invention without the outer cover.

[0021] Figure 3 This is a schematic diagram of the overall structure of the synchronous turning unit of the present invention.

[0022] Figure 4 This is a schematic diagram of the overall structure of the C-shaped coplanar detection unit of the present invention.

[0023] Figure 5 This is a schematic diagram of another embodiment of the synchronous turning unit of the present invention.

[0024] Reference numerals: 1. Horizontal machine tool, 2. Power spindle, 3. Chuck fixture, 4. Spindle head blank, 5. Coordinate calibration box, 6. Calibration platform, 7. Outer cover, 8. First calibration seat, 9. First closed-loop stepping platform, 10. Clamp, 11. Frame seat, 12. Internal hole laser sensor, 13. External circle laser sensor, 14. 45° total reflection prism, 15. Second calibration seat, 16. Second closed-loop stepping platform, 17. Tool holder, 18. Z-axis electric slide, 19. Support arm, 20. Internal boring tool unit, 21. External circle turning unit, 22. Electric lead screw slide, 23. Grating ruler, 24. Reading head, 25. Dovetail caliper, 26. Positioning edging, 27. Coaxial laser cladding unit. Detailed Implementation

[0025] Example 1: like Figures 1 to 4 The lightweight machining device for trailer axle heads shown includes: Controller for overall machine control; A horizontal machine base 1, which has an L-shaped structure, is equipped with a power spindle 2 on its vertical surface. A chuck clamp 3 is fixed to the rotating end of the power spindle 2. The chuck clamp 3 can clamp and lock the shaft head blank 4, and drive the shaft head blank 4 to rotate through the power spindle 2, so as to realize the detection and processing of it. The coordinate calibration box 5 has a hollow structure at the end facing the power spindle 2. The coordinate calibration box 5 includes a calibration platform 6, which is integrally made of three adjacent vertical surfaces. An outer cover 7 is fixed to the outside of the calibration platform 6. The C-shaped coplanar detection unit includes a first calibration seat 8 slidably disposed on the upper part of a calibration platform 6, which is fixed to the calibration platform 6 by bolts. A first closed-loop stepping platform 9 is fixed on the first calibration seat 8. A hollow frame 11 is fixed to the slider of the first closed-loop stepping platform 9 by a clamp 10. The frame 11 is hollow inside, and an inner hole laser sensor 12 and an outer circle laser sensor 13 are respectively fixed to the upper and lower parts away from the hollow end of the frame 11. The inner hole laser sensor 12 and the outer circle laser sensor 13 adopt a time-division multiplexing anti-interference method. Both the inner hole laser sensor 12 and the outer circle laser sensor 13 use 650nm line lasers, and the inner hole laser sensor 12 and the outer circle laser sensor 13 emit lasers alternately. The laser emits at a frequency of 10kHz. The receivers of the inner hole laser sensor 12 and the outer circle laser sensor 13 receive the laser synchronously. Data is collected only when the corresponding sensor emits the laser. The axle head blank 4 can collect 1000 points in one revolution, which fully meets the detection accuracy requirements. A 45° total reflection prism 14 is set in the hollow end of the frame 11, facing the inner hole laser sensor 12 and the outer circle laser sensor 13. The angle of the two sets of 45° total reflection prisms 14 is adjusted by a laser interferometer so that the scanning planes of the two laser beams of the inner hole laser sensor 12 and the outer circle laser sensor 13 are completely coplanar. After the 45° total reflection prism 14 deflects the laser beams of the inner hole laser sensor 12 and the outer circle laser sensor 13 by 90°, it vertically scans the inner hole and outer circle of the axle head. The C-shaped coplanar detection unit uses a hollow frame 11 at the front end as a carrier, with the opening facing the shaft blank 4. The opening width is 10mm larger than the maximum outer diameter of the blank. The inner hole laser sensor 12 and the outer circle laser sensor 13 are installed on the upper and lower sides of the end of the frame 11. The scanning frequency of the inner hole laser sensor 12 and the outer circle laser sensor 13 is 100kHz, and the measurement accuracy is ±0.0005mm. The scanning planes of the inner hole laser sensor 12 and the outer circle laser sensor 13 are strictly coplanar. During scanning, the power spindle 2 drives the shaft blank 4 to rotate one revolution. The inner hole laser sensor 12 and the outer circle laser sensor 13 synchronously collect the inner diameter and outer diameter data of the shaft blank 4 at each angle within a 360° range. The synchronous turning unit is located directly below the first calibration base 8; the detection point of the C-shaped coplanar detection unit and the machining point of the synchronous turning unit are on the same vertical line, and the vertical line is on the plane formed by the axis of the power spindle 2 and the z-axis; A full contour margin verification control unit is integrated inside the controller.

[0026] The lightweight machining device for trailer axle heads of the present invention pre-calibrates the coordinates of the C-shaped coplanar detection unit and the synchronous turning unit through the coordinate calibration box 5, ensuring that the detection end of the C-shaped coplanar detection unit and the machining end of the synchronous turning unit are on the same vertical line; and by adjusting the position of the coordinate calibration box 5 on the horizontal machine tool 1, the horizontal machine tool 1 and the coordinate calibration box 5 are integrated into a reference structure, rigidly locking the coordinate system of the separate C-shaped coplanar detection unit, the synchronous turning unit and the rotation center of the power spindle 2, achieving pre-coaxiality and eliminating the need for later processing. Coordinate unification calculation: the scanned original contour data is directly unified with the power spindle 2 to the reference coordinate system. When the full contour allowance verification and control unit calculates, it ensures accurate and error-free calculation of the machining allowance across the entire domain and automatic determination of eccentricity type. During operation, the shaft head blank 4 of the radial forged seamless steel pipe is clamped on the high-precision spindle chuck fixture 3. The C-shaped coplanar detection unit moves to the entire domain or key section position of the shaft head blank 4. The power spindle 2 drives the shaft head blank 4 to rotate one revolution, completing the circumferential synchronous scanning of the complete inner and outer contours of this area. The first closed-loop stepping platform The machined spindle head blank 4 is then rotated and scanned at high speed to obtain the full contour data of its inner and outer parts. The controller calculates the feasible machining area through the full contour allowance verification control unit and verifies whether the center of the drive spindle is within this area. After verification, the synchronous turning unit feeds along the Z-axis. The internal turning tool and the external turning tool simultaneously turn the inner and outer circles concentric with the spindle at fixed radii and feed rates. After machining, a quality report containing the wall thickness distribution is automatically generated. The machined inner hole and outer circle are both circles centered on the center of the power spindle 2. The axle head blanks are absolutely concentric, and the wall thickness difference at all angles of the same circumference is zero. By strictly controlling the eccentricity and roundness error of the radially forged axle head blank 4, it can be guaranteed that all axle head blanks 4 can pass the verification. For unqualified blanks, they can be rejected in advance to avoid wasting processing time. The processed axle head can achieve zero coaxiality error and zero wall thickness difference with the parameters specified in the drawing. The processing process is simple. The tool only needs to be fed according to a fixed radius without any real-time adjustment. The quality is the most stable. The product quality processed from all qualified axle head blanks 4 is completely consistent.

[0027] The full contour allowance verification control unit calculates the machining allowance of the outer circle and inner hole of any candidate machining center at any angle. When the allowance of the outer circle and inner hole at all angles is greater than or equal to 0, the candidate machining center is a feasible machining area. Within the feasible machining area, the position of the shaft head blank 4 is no longer repeatedly adjusted; instead, the blank's qualification is directly verified. The feasible machining area is the set of all machining center positions that can machine the inner and outer circles that meet the drawing requirements. If the center of the power spindle 2 is within this area, it means there is sufficient machining allowance at all angles, allowing all errors in the blank to be removed, resulting in a shaft head with concentric inner and outer circles. If the center of the power spindle 2 is not within this area, it means there is insufficient machining allowance at at least one angle, making it impossible to machine concentric circles, and the blank is unqualified. When the center of the power spindle 2 falls into the feasible machining area, the synchronous turning unit feeds according to the inner and outer diameter requirements of the shaft head. If the power spindle 2 is not within the feasible machining area, it is determined that the machining allowance of the outer circle or inner hole at at least one angle is insufficient, failing to meet the machining requirements, triggering an automatic alarm, and discarding the 4 shaft head blanks. The specific calculation is as follows: The full profile margin verification control unit predefines calculation parameters, among which The polar angle (0°-360°) of the section of the shaft head blank 4 corresponds to the angle of rotation of the shaft head blank 4. The outer diameter of the 4th shaft blank obtained by scanning is at an angle The actual radius at the location (polar coordinates of the outer contour of the shaft head blank 4); The inner hole of the shaft head blank 4 obtained by scanning is at an angle The actual radius at the location (polar coordinates of the inner contour of the shaft head blank 4); Coordinates of the candidate machining center (spindle rotation center is fixed at (0,0)); The outer radius of the finished product as required by the drawing (fixed value); The inner diameter of the finished product as required by the drawing (fixed value); The machining allowance for the outer ring is calculated as follows: ; For the outer circle of the blank at the angle The original radius at that point, which is the distance from the outer surface of the blank to the geometric center of the outer circle of the blank; for From the candidate machining center to the outer diameter of the shaft head blank 4 The actual distance of the point , For the outer circle of the shaft head blank 4 The coordinates of the point in the rectangular coordinate system (with the geometric center of the outer circle of the shaft head blank 4 as the origin). outer circle of blank The effective radius of the point relative to the candidate machining center, minus To obtain the thickness of metal that needs to be machined away at that angle, i.e., the machining allowance for the outer diameter; when "Time" indicates the angle. At this point, the outer diameter of the blank has sufficient allowance to be machined to the finished radius. If it is negative, it means that the outer diameter of the blank at that position is insufficient and the required outer diameter cannot be machined.

[0028] The machining allowance for the inner circle is calculated as follows: ; For the inner hole of the blank at an angle The original radius at that point is the distance from the inner surface of the shaft head blank 4 to the geometric center of the inner hole of the blank. Candidate machining center to the inner hole of the blank The actual distance between the points; For the inner hole of the shaft head blank 4 The effective radius of the point relative to the candidate machining center; its minus To obtain the thickness of metal that needs to be machined away at this angle, i.e. the machining allowance for the inner hole; when "Time" indicates the angle. At this point, the inner hole of the blank has sufficient allowance to be machined to the finished radius. If it is negative, it means that the outer diameter of the blank at that position is too large and the required inner hole cannot be machined. The difference between calculating the machining allowance for the outer diameter and the inner diameter is that the outer diameter is calculated by subtracting the effective radius from the blank radius and then subtracting the finished radius; the inner hole is calculated by subtracting the blank radius from the effective radius and then subtracting the finished radius. The reason is that the outer diameter is machined from the outside to the inside, while the inner hole is machined from the inside to the outside, and the calculation direction of the allowance is opposite. When calculating the full contour allowance, the control unit can guarantee absolute concentricity: when the center (0,0) of the power spindle 2 is within the feasible machining area, the tool operates at a fixed radius. and The feed ensures that the machined inner and outer circles are perfectly concentric with the center of the power spindle 2, achieving zero wall thickness difference, i.e., the finished wall thickness is perfect. (Fixed value) and angle It is irrelevant; theoretically, the wall thickness difference is 0. If the center of the power spindle 2 is not within the feasible machining area, it means that the allowance of the outer circle or inner hole at at least one angle is insufficient, and it is impossible to machine out the standard inner and outer concentric circles. The blank is directly judged as unqualified.

[0029] The full contour allowance verification control unit also includes a defect determination unit. After receiving an alarm signal, the defect determination unit performs defect determination as follows: by comparing the synchronous correlation of the inner and outer circumferential machining allowances, if the overall allowances are symmetrically deviated in the same direction, it is determined to be a fixture clamping axis offset; if the allowances are disordered and independent, it is determined to be a blank manufacturing eccentricity; after classification and identification, only the clamping eccentricity is corrected by chuck fixture 3D micro-alignment, and after correction, the full contour allowance verification continues. When it is determined to be a blank manufacturing eccentricity, the blank is directly scrapped.

[0030] The characteristics of clamping eccentricity (manual installation offset, not inherent to the shaft head blank 4) are as follows: On the full circumference, the inner and outer allowances shift synchronously and periodically in the same direction. On one side, the outer allowance is generally larger and the inner allowance is also synchronously larger. On the other side, the outer allowance is generally smaller and the inner allowance is also synchronously smaller. The defect judgment unit determines that the inner and outer allowances shift sinusoidally and symmetrically across the entire area, indicating clamping eccentricity. The chuck fixture 3 needs to be fine-tuned or the shaft head blank 4 needs to be readjusted to align the power spindle 2 reference.

[0031] The characteristics of the original eccentricity of the forging body of the shaft head blank 4 (which is inherent to the shaft head blank 4 and is unrelated to clamping) are as follows: the internal and external distortions of the shaft head blank 4 are independent and unrelated, the outer diameter allowance is sometimes large and sometimes small, the inner diameter allowance is chaotic and has no synchronous pattern, and the two offsets are not linked and are not in the same direction; the defect judgment unit judges that: the allowance is chaotic and has no synchronous symmetry pattern, which determines that the shaft head blank 4 is eccentric on its own and there is no problem with clamping.

[0032] The full contour allowance verification control unit also includes a tool feed calculation unit. The tool feed calculation unit sequentially obtains the maximum outer diameter and minimum inner diameter of the shaft head after scanning one circumference; and calculates the difference between the actual inner and outer diameter parameters calibrated in this area and the inner and outer diameter parameters obtained by scanning. Finally, the difference is divided by the maximum cutting amount of the synchronous turning unit to determine the number of feeds. When the number of feeds is a decimal, the decimal is discarded, and 1 is added to the number of feeds to obtain the total number of feeds. Finally, the difference is divided by the number of feeds to obtain the feed amount for each feed. The synchronous turning unit performs the turning work according to the total number of feeds and the feed amount for each feed. It first calculates the maximum cutting amount of one circumference of the surface to be machined, then calculates the number of tool feeds based on the maximum cutting amount and the maximum feed amount of the track, and finally distributes the maximum cutting amount evenly across the number of tool feeds.

[0033] The synchronous turning unit is located directly below the first calibration base 8; the synchronous turning unit includes a second calibration base 15 fixed to the calibration platform 6 by bolts, and a second closed-loop stepping platform 16 is fixed on the second calibration base 15; a tool holder 17 is fixed on the slider of the second closed-loop stepping platform 16, and two sets of Z-axis electric slides 18 are fixed on the tool holder 17 with vertical offset; an internal boring tool unit 20 and an external turning unit 2 are fixed on the slider of the Z-axis electric slide 18 by a support arm 19. 1. During operation, the internal boring tool unit 20 and the external turning unit 21 are translated to the inner and outer walls of the shaft head blank 4 by the second closed-loop stepping platform 16. Then, the internal boring tool unit 20 and the external turning unit 21 are driven by the two sets of Z-axis electric slides 18 on the tool holder 17 to feed the inner and outer walls of the shaft head blank 4. The second closed-loop stepping platform 16 slides along the axial direction of the shaft head blank 4 and drives the shaft head blank 4 to rotate circumferentially by the power spindle 2 to complete the turning of the inner and outer wall areas of the shaft head blank 4.

[0034] The first closed-loop stepping platform 9 and the second closed-loop stepping platform 16 include an electric lead screw slide 22. An optical grating ruler 23 is fixed to the outside of the slide base of the electric lead screw slide 22. The reading head 24 equipped with the optical grating ruler 23 is fixed to the side of the slider of the electric lead screw slide 22. The electric lead screw slide 22 can drive the slider to slide linearly along the slide base. During sliding, the optical grating ruler 23 and the reading head 24 cooperate to achieve accurate monitoring of the slider displacement.

[0035] The horizontal machine tool 1 has an integrally formed dovetail rail 25 on its horizontal surface; the dovetail rail 25 is fixed with a positioning edge 26; the coordinate calibration box 5 is movably fitted with the dovetail rail 25 and fixed to the positioning edge 26 by bolts; in use, the coordinate calibration box 5 is replaced and installed as a whole according to different axle head models.

[0036] The internal boring tool unit 20 and the external turning unit 21 are passive carbide tools held by tool chucks or grinding tools driven by grinding drive equipment. Through the high-speed rotation power of the power spindle 2, the shaft head blank 4 workpiece is driven to rotate at high speed, and the passive carbide tool performs passive turning on the shaft head blank 4. When an automatic force grinding tool is used, the power spindle 2 acts as a rotation reversing unit for the shaft head blank 4, and the grinding tool actively turns the inner and outer walls of the shaft blank.

[0037] Example 2: like Figure 5The lightweight machining device for trailer axle heads shown includes a support arm 19 with a coaxial laser cladding unit 27 fixed to the side of the internal boring tool unit 20. The cladding end of the coaxial laser cladding unit 27 is coplanar with the machining surface of the boring end of the internal boring tool unit 20. The coaxial laser cladding unit 27 includes a laser cladding head, which uses an annular powder feeding nozzle. When a defect is detected in the axle head blank 4, it is determined whether the defect location is a critical area. If so, it is scrapped. If not, the area and depth of the defect are determined. If they exceed a set value, further processing is performed. For scrapping, when the defect does not exceed the set value, the defective area is clad by the coaxial laser cladding unit 27, and then machined. In addition, the coaxial laser cladding unit 27 is also used for surface enhancement. When machining to the bearing position and oil seal position, laser cladding is started simultaneously to directly clad the nickel-based tungsten carbide alloy reinforcement layer on the newly machined near-surface. Since the surface after machining has high activity, the bonding strength between the cladding layer and the substrate is greatly improved, and deformation caused by subsequent heat treatment can be avoided. The cladding powder is nickel-based tungsten carbide alloy, and the cladding thickness is adjustable from 0.3 to 0.8 mm.

[0038] The above embodiments are merely preferred embodiments of the present invention. Therefore, all equivalent changes or modifications made to the structure, features and principles described in the claims of the present invention are included within the scope of the present invention.

Claims

1. A lightweight machining device for trailer axle heads, characterized in that: include: Controller for overall machine control; A horizontal machine tool, wherein the horizontal machine tool has an L-shaped structure, a power spindle is mounted on the vertical surface of the horizontal machine tool, and a chuck clamp is fixed to the rotating end of the power spindle; The coordinate calibration box has a hollow structure at the end facing the power spindle. The coordinate calibration box includes a calibration platform, which is integrally formed from three adjacent vertical surfaces. An outer cover is fixed to the outside of the calibration platform. The C-shaped coplanar detection unit includes a first calibration seat slidably disposed on the upper part of a calibration platform, the first calibration seat being fixed to the calibration platform by bolts; a first closed-loop stepping platform is fixed on the first calibration seat; a hollow frame is fixed to the slider of the first closed-loop stepping platform by a clamp; the frame is hollow inside, and an inner hole laser sensor and an outer circular laser sensor are respectively fixed to the upper and lower parts of the frame away from the hollow end; a 45° total reflection prism is set on the hollow end of the frame facing the inner hole laser sensor and the outer circular laser sensor; the angles of the two sets of 45° total reflection prisms are adjusted by a laser interferometer so that the scanning planes of the two laser beams of the inner hole laser sensor and the outer circular laser sensor are completely coplanar; A synchronous turning unit is located directly below the first calibration base; the detection point of the C-shaped coplanar detection unit and the machining point of the synchronous turning unit are on the same vertical line, and the vertical line is on the plane formed by the axis of the power spindle and the z-axis; A full contour margin verification control unit is integrated inside the controller.

2. The lightweight machining device for trailer axle heads according to claim 1, characterized in that: The full contour allowance verification and control unit calculates the machining allowance of the outer circle and inner hole of any candidate machining center at any angle. When the allowance of the outer circle and inner hole at all angles is greater than or equal to 0, the candidate machining center is a feasible machining area. When the center of the power spindle falls into the feasible machining area, the synchronous turning unit feeds according to the inner and outer diameter requirements of the axle head. If the power spindle is not in the feasible machining area, it is determined that the machining allowance of the outer circle or inner hole at at least one angle is insufficient and cannot meet the machining requirements. An alarm is automatically triggered, and the axle head blank is rejected.

3. The lightweight machining device for trailer axle heads according to claim 2, characterized in that: The full contour allowance verification control unit also includes a defect determination unit. After receiving an alarm signal, the defect determination unit performs defect determination as follows: by comparing the synchronous correlation of the inner and outer circumferential machining allowances, if the overall allowances are symmetrically deviated in the same direction, it is determined to be a fixture clamping axis offset; if the allowances are disordered and independent, it is determined to be a blank manufacturing eccentricity; after classification and identification, only the clamping eccentricity is corrected by three-dimensional micro-alignment of the chuck fixture, and after correction, the full contour allowance verification continues. When it is determined to be a blank manufacturing eccentricity, the blank is directly scrapped.

4. The lightweight machining device for trailer axle heads according to claim 3, characterized in that: The full contour allowance verification control unit also includes a tool feed calculation unit. The tool feed calculation unit sequentially obtains the largest outer diameter and the smallest inner diameter of the shaft head after scanning one revolution; and calculates the difference between the actual inner and outer diameter parameters calibrated in this area and the inner and outer diameter parameters obtained by scanning. Finally, the difference is divided by the maximum cutting amount of the synchronous turning unit to determine the number of feeds. When the number of feeds is a decimal, the decimal is discarded, and the number of feeds is incremented by 1 to obtain the total number of feeds. Finally, the difference is divided by the number of feeds to obtain the feed amount for each feed. The synchronous turning unit performs the turning operation according to the total number of feeds and the feed amount for each feed.

5. The lightweight machining device for trailer axle heads according to claim 1, characterized in that: The synchronous turning unit is located directly below the first calibration base; the synchronous turning unit includes a second calibration base that is fixed to the calibration base by bolts, and a second closed-loop stepping platform is fixed on the second calibration base; a tool holder is fixed on the slider of the second closed-loop stepping platform, and two sets of Z-axis electric slides are fixed on the tool holder by offset vertically; an internal boring tool unit and an external turning unit are fixed on the slider of the Z-axis electric slide by a support arm.

6. The lightweight machining device for trailer axle heads according to claim 5, characterized in that: The first closed-loop stepping platform and the second closed-loop stepping platform include an electric lead screw slide. An optical grating ruler is fixed to the outside of the slide base of the electric lead screw slide, and the reading head of the optical grating ruler is fixed to the side of the slider of the electric lead screw slide.

7. The lightweight machining device for trailer axle heads according to claim 1, characterized in that: The horizontal machine tool has an integrally formed dovetail rail on its horizontal surface; the dovetail rail is fixed with a positioning rim; the coordinate calibration box is movably fitted with the dovetail rail and fixed to the positioning rim with bolts.

8. The lightweight machining device for trailer axle heads according to claim 5, characterized in that: The arm is fixed with a coaxial laser cladding unit on the side of the internal boring tool unit. The cladding end of the coaxial laser cladding unit is coplanar with the machining surface of the boring end of the internal boring tool unit. The coaxial laser cladding unit includes a laser cladding head, which is a ring-shaped powder feeding nozzle.

9. The lightweight machining device for trailer axle heads according to claim 8, characterized in that: The cladding powder is a nickel-based tungsten carbide alloy, and the cladding thickness is adjustable from 0.3 to 0.8 mm.

10. The lightweight machining device for trailer axle heads according to claim 5, characterized in that: The internal boring tool unit and the external turning unit are passive alloy tools held by tool chucks or grinding tools driven by grinding drive equipment.

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