A laser reaming device and method for an automotive brake drum

Abstract

The application discloses a laser reaming machining device and method for an automobile brake drum, and belongs to the field of vehicle accessory manufacturing. The laser reaming machining device for the automobile brake drum comprises a device main body, the device main body comprises a base, a plurality of machining rotary tables and a laser machining device are arranged on the base, the laser machining device comprises a shaft moving system, a plurality of laser head modules are arranged in the shaft moving system; the machining rotary table comprises a rotary table base, a chuck is rotatably arranged on the rotary table base, a plurality of clamping claws and supporting rods are arranged on the chuck, and the upper ends of the supporting rods are used for supporting end face panels of the brake drum. The multi-station rotary table is matched with the same number of laser head modules one by one, reaming machining can be simultaneously implemented on a plurality of brake drums, and the batch machining capacity is doubled. The inner ring supporting rods first support the end faces of the brake drum, and then the outer ring clamping claws clamp the outer walls, the supporting and clamping are not interfered with each other, the clamping stress is uniform, and clamping deformation of the thin wall part of the brake drum is effectively avoided.

Description

Technical Field

[0001] This invention relates to the field of vehicle parts manufacturing, and in particular to a laser hole-reaming equipment and method for automotive brake drums. Background Technology

[0002] The brake drum is a key load-bearing component in a drum braking system, typically formed using casting or spinning processes. After the blank is formed, the center of the brake drum needs to be enlarged and precision-machined to ensure the roundness, dimensional accuracy, and coaxiality of the center hole relative to the inner brake surface. The quality of the center hole enlargement directly affects the dynamic balance performance of the wheel after assembly, as well as the uniformity of the fit between the brake pads and the brake drum. Insufficient machining precision can easily lead to vehicle braking vibration, abnormal noise, and uneven brake pad wear.

[0003] Currently, the machining of brake drum center holes in the industrial sector mainly relies on CNC boring machines and conventional lathes for cutting. The specific process is as follows: the brake drum blank is locked onto the machine spindle by a chuck, the spindle drives the workpiece to rotate as a whole, and the boring tool or turning tool feeds radially to complete the layered cutting of the center hole. In automated production lines, this type of equipment is often equipped with single-station loading and unloading robots to complete the workpiece loading, positioning cutting, and unloading flow one by one. If production capacity needs to be increased, multiple single machines must be added and arranged in parallel.

[0004] Existing boring and turning machining solutions have multiple shortcomings: the equipment relies on contact cutting with hard metal tools, and the casting hard spots and sand holes inside the brake drum blank can easily cause rapid tool wear, requiring frequent machine stops to replace the inserts and compensate for tool errors, which greatly reduces the effective machining time; most commercially available machining equipment operates in a single-station mode, with each machine only able to process one workpiece at a time. Even with multiple machines operating in parallel, each machine independently cycles for loading, unloading, and cutting, resulting in significant waiting time and low overall processing efficiency for the entire production line; at the same time, contact cutting generates large radial cutting forces, which can easily lead to defects such as hole wall vibration marks and out-of-roundness during machining, making it difficult to reliably guarantee the high-precision coaxiality requirements of the center hole. Summary of the Invention

[0005] This invention addresses the problems of low machining accuracy, high tool wear, and the need for sequential loading and unloading of multiple workpieces on a single machine when using traditional contact machining processes for expanding brake drums. It provides a laser-based equipment for expanding brake drums.

[0006] To solve the above problems, the technical solution adopted by the present invention is a laser enlarging processing equipment for automotive brake drums, comprising a main body, a base, a plurality of processing turntables and a laser processing device on the base, the laser processing device comprising a shaft drive system, a plurality of laser head modules installed in the shaft drive system, the number of laser head modules corresponding to the number and position of the processing turntables; the processing turntable comprises a turntable base, a chuck rotatably disposed on the turntable base, a plurality of jaws and support rods disposed on the chuck, the plurality of jaws and the plurality of support rods being circumferentially distributed, and the support rods being located within the circle of the jaws, the upper end of the support rods being used to support the end face panel of the brake drum and being higher than the upper end of the jaws. This solution uses laser non-contact thermal processing to replace traditional turning and boring processes. During processing, no radial cutting force acts on the brake drum workpiece, eliminating defects such as hole wall vibration marks and thin-wall deformation. This significantly improves the roundness and concentricity accuracy of the brake drum's center hole, while avoiding tool wear, frequent tool changes, and time-consuming dimensional compensation. It also eliminates multiple subsequent continuous cutting processes, allowing for one-time center hole enlargement, significantly shortening the single-piece processing cycle and reducing tool consumable procurement and maintenance costs. Furthermore, the equipment uses a multi-station rotary table matched with the same number of laser head modules, enabling simultaneous enlargement processing of multiple brake drums. The internal workstations employ a layered clamping structure where the inner ring support rod first supports the brake drum end face, and the outer ring claws then clamp the outer wall. The support and clamping areas are separated and do not interfere with each other, ensuring uniform force on the workpiece during clamping and further preventing deformation of the brake drum shell during clamping, thus stabilizing the finished product's processing accuracy.

[0007] Preferably, multiple processing turntables are arranged along a first direction, and the laser head module is located on one side of the processing turntable along a second direction and can move to above the processing turntable. The first direction and the second direction are perpendicular to each other. The axial drive system includes a crossbeam. Along the first direction, both sides of the base are provided with first guide rails and first racks. The first guide rails and first racks are arranged along the second direction. Both ends of the crossbeam are provided with crossbeam mounting seats. The crossbeam mounting seats are slidably mounted on the first guide rails on the corresponding sides. The crossbeam mounting seats are also provided with crossbeam drive motors. The output shaft of the crossbeam drive motor is provided with a first gear, which meshes with the first rack on the corresponding side. Multiple laser head modules are mounted on the crossbeam. The crossbeam adopts a double-sided gear and rack synchronous drive, which has strong transmission rigidity, high crossbeam running synchronization, and stable movement positioning accuracy. The crossbeam can move horizontally as a whole to cover all processing stations. A single crossbeam can carry all laser modules, simplifying the overall machine drive structure and reducing equipment manufacturing costs.

[0008] Preferably, the laser head module includes a horizontal slide, a second rack and a second guide rail on the crossbeam, the horizontal slide being movably mounted on the second guide rail, a module drive motor on the horizontal slide, a second gear mounted on the output shaft of the module drive motor, the second gear meshing with the second rack; a forward extension beam is also mounted on the horizontal slide, the forward extension beam being arranged along a second direction and extending towards the machining turntable, a vertical slide being mounted on the end of the forward extension beam near the machining turntable via a lead screw assembly, and the laser head body being mounted on the vertical slide. A single module can move independently horizontally and vertically, and the three-axis linkage flexibly adapts to the inner hole contours of different specifications of brake drums; the lead screw drives the vertical slide to rise and fall, the laser head height is adjusted accordingly, and the processing process can follow the workpiece surface in real time, ensuring a constant laser cutting focal length and improving the smoothness and dimensional consistency of the inner wall of the enlarged hole.

[0009] Preferably, the turntable base is equipped with a rotary motor, which is eccentrically positioned relative to the rotation center of the chuck. A drive gear is mounted on the output shaft of the rotary motor, and a driven gear is located at the lower part of the turntable base. The drive gear meshes with the driven gear. The eccentrically positioned rotary motor makes full use of the unused space inside the turntable base, reducing the overall area occupied by a single turntable and facilitating the compact arrangement of multiple turntables. The gear meshing transmission provides high torque and smooth operation, while the uniform rotation of the chuck eliminates cutting vibration marks and ensures that the roundness of the brake drum's center hole meets the standard.

[0010] Preferably, the upper end of the support rod is machined with a threaded hole and an adjusting screw is installed thereon. The lower end of the support rod is provided with an adjusting plate, and the adjusting plate has an elongated hole. The adjusting plate is installed on the chuck through the elongated hole, which is arranged radially along the chuck. A dustproof plate is also installed at the lower part of the jaws, and the dustproof plate is in contact with the upper surface of the chuck. The radial elongated hole, together with the top adjusting screw, allows for flexible adjustment of the support point and support height, adapting to brake drums of various diameters and thicknesses. The dustproof plate fully covers the chuck sliding track, preventing laser slag and metal dust from entering the transmission gap, reducing chuck jamming failures, and extending the service life of the fixture.

[0011] Preferably, the system also includes a waste conveying platform. The conveying direction of the waste conveying platform is set along a second direction. The receiving end of the waste conveying platform extends into the base and is located below the area where the processing turntable is located. The discharge end of the waste conveying platform is provided with a waste hopper. The base is provided with a mounting platform, and the processing turntable is mounted on the mounting platform. The center of the mounting platform is hollowed out. At the bottom of the mounting platform, a material drop guide plate is provided around the hollowed-out window. The material drop guide plate is inclined, and the lower end of the inclined surface faces the receiving end of the waste conveying platform. The upper surface of the material drop guide plate is provided with a guide protrusion. Processing waste can fall directly through the hollowed-out area in the center of the turntable. The inclined guide plate and the guide protrusion prevent waste from accumulating and blocking. The waste automatically falls into the conveying platform for unified collection, eliminating the need for continuous manual cleaning of the workstation, reducing labor input, and improving the workshop working environment.

[0012] Preferably, the system also includes an external frame comprising multiple columns, the tops of which collectively form a second-floor platform. The main body of the equipment is situated within the space enclosed by the columns and the second-floor platform, on which the supporting equipment for the main body is arranged. The base is further protected by an outer sheet metal enclosure. The upper platform centrally houses the laser, water chiller, power distribution cabinet, and other supporting components, making full use of vertical space and significantly reducing the equipment's floor space requirement. The outer sheet metal enclosure fully encloses the processing area, blocking laser radiation and sparks, thus improving operational safety.

[0013] Preferably, within the outer frame, the bottom surface of the second-floor platform is equipped with multiple dust collection boxes, the number of which corresponds to the number of processing turntables, and the dust collection boxes are located above the corresponding processing turntables. Each dust collection box corresponds one-to-one with a processing station, adsorbing the fumes generated by laser cutting at close range, shortening the fume adsorption path, increasing dust removal efficiency, and preventing the spread of fumes and dust that pollutes the workshop.

[0014] On the other hand, the present invention also provides a laser reaming method for automotive brake drums, using the aforementioned laser reaming equipment for automotive brake drums, and the method includes the following steps: S1. The loading and unloading equipment places several brake drums horizontally on the support rod of the processing turntable, and the chuck clamps and fixes the brake drums. S2. The crossbeam moves each laser head module to the top of the processing turntable, and the vertical slide descends, causing the laser head body to descend to the processing position; S3. The chuck rotates, and at the same time, the laser head emits laser light for processing; S4. After processing is completed, the chuck releases the brake drum, and the loading and unloading equipment removes the brake drum.

[0015] This solution employs automatic loading and unloading, automatic positioning, and laser non-contact hole enlargement, eliminating the need for multiple processes such as rough boring, semi-finish boring, and fine boring. It completes the center hole enlargement of the brake drum in one step, without tool wear or frequent tool changes, thus shortening the processing time per piece and reducing material costs.

[0016] Furthermore, step S2 includes: S2-1. Move the laser head body to the center position of the brake drum, with the nozzle 0.5-1mm above the workpiece surface; S2-2. The laser head body moves radially outward along the brake drum. When it passes the edge of the inner hole of the brake drum, the capacitance sensor inside the laser head body undergoes a capacitance jump, and the coordinates of the laser head body at this time are recorded. S2-3. Repeat step S2-2 at least three times, each time moving the laser head body along a different radius of the brake drum; S2-4. Based on the coordinate information of the multiple sets of laser head bodies recorded in S2-3, recalibrate the center of the moving drum inner hole as the processing reference.

[0017] Multi-point capacitor edge finding automatically corrects workpiece clamping eccentricity, accurately locks the true center of the brake drum as the machining reference, eliminates positioning deviation, ensures the concentricity of the center hole and the outer circle of the brake drum after hole enlargement, and improves subsequent wheel dynamic balance and braking stability.

[0018] As can be seen from the above technical solutions, the beneficial effects of this invention are as follows: This invention uses laser non-contact thermal processing to replace the traditional turning and boring cutting process, eliminating radial cutting force during processing, completely eliminating the problems of vibration marks and thin-wall deformation on the brake drum hole wall, significantly improving the roundness and concentricity of the center hole, and eliminating tool wear, saving multiple boring processes, and forming the center hole in one step, effectively shortening the processing time of a single piece and reducing tool consumables and maintenance costs; the equipment can be matched with an equal number of multi-processing turntables and laser head modules for simultaneous batch processing. The turntable adopts layered clamping with internal support rods and external jaws, ensuring uniform force on the workpiece, avoiding clamping deformation, and stabilizing the accuracy of the finished product; the entire machine's crossbeam is synchronously driven by gears and racks on both sides, which can fully cover all workstations. A single crossbeam carries all modules, simplifying the drive structure and reducing manufacturing costs. Each laser head module can independently perform three-axis linkage, with the lead screw driving the vertical slide. Real-time focus adjustment ensures smooth inner wall and uniform dimensions; the eccentrically arranged rotary motor on the turntable saves space, and the gear transmission ensures smooth operation. Combined with radially adjustable support rods and chuck dustproof plates, it adapts to various brake drum specifications while reducing clamping failures caused by dust and slag; the hollowed-out center of the turntable, along with an inclined material guide plate and waste conveying platform, enables automatic waste collection, eliminating the need for manual cleaning stations; the equipment is equipped with an external frame with a second-floor platform, where auxiliary equipment is centrally located to reduce floor space; the outer sheet metal enclosed processing area has independent dust collection boxes at each workstation for close-range dust adsorption, balancing operational safety and workshop environment; the supporting processing methods enable fully automatic loading and unloading and multi-point capacitive edge-finding positioning; multi-point coordinate acquisition automatically corrects workpiece eccentricity, accurately locking the processing datum, further improving brake drum concentricity, and optimizing wheel dynamic balance and overall vehicle braking performance. Attached Figure Description

[0019] To more clearly illustrate the technical solution of this patent, the drawings used in the description will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this patent. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0020] Figure 1 This is a structural schematic diagram of a specific embodiment of the present invention.

[0021] Figure 2 This is a schematic diagram of the internal structure of the device body in a specific embodiment of the present invention.

[0022] Figure 3 This is a schematic diagram of the laser head module in a specific embodiment of the present invention.

[0023] Figure 4 This is a schematic diagram of the machining turntable in a specific embodiment of the present invention. Figure 1 .

[0024] Figure 5This is a schematic diagram of the machining turntable in a specific embodiment of the present invention. Figure 1 .

[0025] Figure 6 This is a schematic diagram of the material guide plate in a specific embodiment of the present invention.

[0026] Figure 7 This is a schematic diagram of the dust collector housing in a specific embodiment of the present invention.

[0027] Explanation of main figure symbols 01. Main body of equipment; 02. Waste conveying platform; 03. External frame; 1. Base; 2. Processing turntable; 2-1. Turntable base; 2-2. Chuck; 2-3. Jaw; 2-4. Support rod; 2-5. Rotary motor; 2-6. Drive gear; 2-7. Driven gear; 2-8. Adjusting plate; 2-9. Long hole; 2-10. Dustproof plate; 2-11. Adjusting screw; 3. Crossbeam; 4. Laser head module; 4-1. Horizontal slide; 4 -2. Vertical slide, 4-3. Forward beam, 4-4. Laser head body, 4-5. Lead screw assembly, 4-6. Module drive motor, 5. First guide rail, 6. First rack, 7. Crossbeam mounting base, 8. Crossbeam drive motor, 9. Second guide rail, 10. Mounting platform, 11. Unloading guide plate, 12. Guide protrusion, 13. Column, 14. Second floor platform, 15. Peripheral sheet metal, 16. Dust collection box, 17. Waste hopper, 18. Second rack. Detailed Implementation

[0028] To make the objectives, features, and advantages of this patent more apparent and understandable, the technical solutions of this patent will be clearly and completely described below with reference to the accompanying drawings of the specific embodiments. Obviously, the embodiments described below are only some embodiments of this patent, and not all embodiments. Based on the embodiments of this patent, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this patent.

[0029] Example 1 A laser enlargement processing equipment for automotive brake drums includes a main body 01, which includes a base 1. The base 1 is provided with multiple processing turntables 2 and a laser processing device. The laser processing device includes a shaft drive system, and multiple laser head modules 4 are installed in the shaft drive system. The number of laser head modules 4 corresponds to the number and position of the processing turntables 2. The machining turntable 2 includes a turntable base 2-1, on which a chuck 2-2 is rotatably mounted. The chuck 2-2 is provided with multiple jaws 2-3 and support rods 2-4. The multiple jaws 2-3 and multiple support rods 2-4 are distributed in a circumferential manner, and the support rods 2-4 are located inside the circle of the jaws 2-3. The upper end of the support rods 2-4 is used to support the end face panel of the brake drum and is higher than the upper end of the jaws 2-3.

[0030] Multiple processing turntables 2 are arranged along a first direction, and laser head modules 4 are located on one side of the processing turntable 2 along a second direction and can be moved to above the processing turntable 2. The first direction and the second direction are perpendicular to each other. The axial movement system includes a crossbeam 3. Along the first direction, the base 1 has a first guide rail 5 and a first rack 6 on both sides. The first guide rail 5 and the first rack 6 are arranged along the second direction. The crossbeam 3 has a crossbeam mounting seat 7 at both ends. The crossbeam mounting seat 7 is slidably mounted on the first guide rail 5 on the corresponding side. The crossbeam mounting seat 7 is also provided with a crossbeam drive motor 8. The output shaft of the crossbeam drive motor 8 is provided with a first gear, which meshes with the first rack 6 on the corresponding side. Multiple laser head modules 4 are mounted on the crossbeam 3.

[0031] The laser head module 4 includes a horizontal slide 4-1. A second rack 18 and a second guide rail 9 are provided on the crossbeam 3. The horizontal slide 4-1 is movably mounted on the second guide rail 9. A module drive motor 4-6 is provided on the horizontal slide 4-1. A second gear is mounted on the output shaft of the module drive motor 4-6, and the second gear meshes with the second rack 18. A forward extension beam 4-3 is also mounted on the horizontal slide 4-1. The forward extension beam 4-3 is arranged along a second direction and extends towards the processing turntable 2. A vertical slide 4-2 is mounted on the end of the forward extension beam 4-3 near the processing turntable 2 through a lead screw assembly 4-5. The laser head body 4-4 is mounted on the vertical slide 4-2.

[0032] The turntable base 2-1 is provided with a rotary motor 2-5, which is eccentrically positioned relative to the rotation center of the chuck 2-2. A drive gear 2-6 is mounted on the output shaft of the rotary motor 2-5, and a driven gear 2-7 is provided at the lower part of the turntable base 2-1. The drive gear 2-6 meshes with the driven gear 2-7.

[0033] The upper end of the support rod 2-4 is machined with a threaded hole and an adjusting screw 2-11 is installed thereon. The lower end of the support rod 2-4 is provided with an adjusting plate 2-8. An elongated hole 2-9 is opened on the adjusting plate 2-8. The adjusting plate 2-8 is installed on the chuck 2-2 through the elongated hole 2-9. The elongated hole 2-9 is arranged radially along the chuck 2-2. A dustproof plate 2-10 is also installed on the lower part of the jaw 2-3. The dustproof plate 2-10 is in contact with the upper surface of the chuck 2-2.

[0034] It also includes a waste conveying platform 02, the conveying direction of which is set along the second direction. The receiving end of the waste conveying platform 02 extends into the base 1 and is located below the area where the processing turntable 2 is located. The discharge end of the waste conveying platform 02 is provided with a waste hopper 17. The base 1 is provided with a mounting platform 10, and the processing turntable 2 is mounted on the mounting platform 10. The middle of the mounting platform 10 is hollowed out. At the bottom of the mounting platform 10, a material drop guide plate 11 is provided around the hollow window. The material drop guide plate 11 is inclined, and the lower end of the inclined surface faces the receiving end of the waste conveying platform 02. The upper surface of the material drop guide plate 11 is provided with a guide protrusion 12.

[0035] It also includes an external frame 03, which includes multiple columns 13. A second-floor platform 14 is provided on the top of the columns 13. The main body of the equipment 01 is located in the space enclosed by the columns 13 and the second-floor platform 14. The supporting equipment of the main body of the equipment 01 is arranged on the second-floor platform 14. The base 1 is also provided with an outer sheet metal 15.

[0036] Inside the outer frame 03, the bottom surface of the second-floor platform 14 is provided with multiple dust collection boxes 16, the number of which corresponds to the number of processing turntables 2, and the dust collection boxes 16 are located above the corresponding processing turntables 2.

[0037] Example 2 This embodiment further provides a laser reaming method for automotive brake drums, using the laser reaming equipment for automotive brake drums from Embodiment 1. The method includes the following steps: S1. The loading and unloading equipment places several brake drums horizontally on the support rods 2-4 of the processing turntable 2, and the chucks 2-3 clamp and fix the brake drums. S2. The crossbeam 3 moves each laser head module 4 to the top of the processing turntable 2, and the vertical slide 4-2 descends, causing the laser head body 4-4 to descend to the processing position; S3. The chuck 2-2 rotates, and at the same time the laser head body 4-4 emits laser light for processing; S4. After processing is completed, chuck 2-2 releases the brake drum, and the loading and unloading equipment removes the brake drum.

[0038] Step S2 includes: S2-1. Move the laser head body 4-4 to the center position of the brake drum, with the nozzle 0.5-1mm above the workpiece surface; S2-2. The laser head body 4-4 moves radially outward along the brake drum. When it passes the edge of the inner hole of the brake drum, the capacitance sensor inside the laser head body 4-4 experiences a capacitance jump. The coordinates of the laser head body 4-4 at this time are recorded. S2-3. Repeat step S2-2 at least three times, each time moving the laser head body 4-4 along a different radius of the brake drum; S2-4. Based on the coordinate information of multiple laser head bodies 4-4 recorded in S2-3, recalibrate the center of the moving drum inner hole as the processing reference.

[0039] Specifically: S1. The external robotic arm, acting as a loading and unloading device, grabs the brake drum to be processed from the stacking area and smoothly transports it horizontally to the top of the processing turntable 2. It slowly lowers the brake drum so that the bottom end face of the brake drum is completely attached to the top of the support rod 2-4. The workpiece is pre-supported horizontally by multiple support rods 2-4. Then, the internal rotary motor 2-5 of the turntable base 2-1 drives the chuck 2-2 to rotate, which drives the jaws 2-3 to synchronously retract radially inward. Multiple sets of jaws 2-3 simultaneously clamp the outer wall of the brake drum, completing the centering and clamping of the brake drum. After clamping, the robotic arm exits the processing area inside the external frame 03, and the corresponding roller shutter door of the outer sheet metal 15 closes to isolate processing fumes and laser sparks.

[0040] S2. The crossbeam drive motors 8 on both sides of the base 1 drive the crossbeam 3 to move laterally along the first guide rail 5, synchronously moving all laser head modules 4 to the work position directly above the corresponding processing turntable 2; the drive motors 4-6 of each module drive the horizontal slide 4-1 to make small adjustments and positioning on the second guide rail 9 of the crossbeam 3, and then the lead screw assembly 4-5 drives the vertical slide 4-2 to descend vertically, lowering the laser head body 4-4 to the preset processing height range. This step is divided into four positioning processes: S2-1. The horizontal slide 4-1 and the vertical slide 4-2 work together to move the laser head body 4-4 to the estimated center position of the brake drum. The distance between the bottom nozzle of the laser head body 4-4 and the upper surface of the brake drum is precisely adjusted to maintain a constant height of 0.5mm to 1mm to ensure stable detection by the capacitive sensor. S2-2. The CNC system controls the laser head body 4-4 to move outward at a constant speed along the radial direction of the brake drum. When the nozzle passes the edge of the brake inner hole, the built-in capacitance sensor of the laser head body 4-4 detects the sudden change in metal spacing and generates a capacitance jump. The equipment control system collects and stores the X and Y coordinate data of the laser head body 4-4 at this moment in real time. S2-3. The system automatically changes the detection radius angle and repeats the S2-2 radial edge detection operation every 120° interval, accumulating at least three sets of edge coordinate acquisitions from different orientations to eliminate positioning errors caused by single-sided detection. S2-4. The control system recalculates the true center coordinates of the brake drum's inner hole by fitting and calculating three or more sets of acquired coordinates. It then automatically sets these coordinates as the processing reference for subsequent laser hole enlargement and simultaneously corrects the equipment's processing trajectory parameters to compensate for the workpiece clamping eccentricity.

[0041] S3. After the edge-finding and calibration process is completed, the equipment starts the processing program. The internal rotary motor 2-5 of the turntable base 2-1 drives the chuck 2-2 to rotate at a constant speed through the drive gear 2-6 and the driven gear 2-7, so that the brake drum rotates synchronously and smoothly. At the same time, the laser starts to output a laser beam, and the laser head body 4-4 emits a laser downward, performing non-contact hole-expanding cutting on the central area of ​​the brake drum along the preset inner hole contour. During the processing, the lead screw assembly 4-5 continuously drives the vertical slide 4-2 to move slightly to maintain a constant distance between the nozzle and the workpiece. The molten slag generated by the cutting directly passes through the hollow window of the mounting table 10 and slides down to the waste conveying platform 02 for automatic transfer via the material guide plate 11.

[0042] S4. After the entire enlargement contour cutting is completed, the laser stops emitting light, the chuck 2-2 stops rotating and drives the jaws 2-3 to release radially outward, releasing the clamping constraint on the outer wall of the brake drum; the front roller shutter door of the outer sheet metal 15 opens automatically, and the loading and unloading robot arm extends into the processing area again, clamps the processed brake drum and transports it to the finished product storage area, waiting for the next batch of workpieces to be processed to be loaded, and the entire processing process is executed in a cycle.

[0043] As can be seen from the above embodiments, the advantages of the present invention are: This equipment employs a multi-station structure with multiple processing turntables matched one-to-one with corresponding laser head modules, enabling simultaneous processing of multiple brake drums and significantly improving batch processing capacity. The internal structure of the processing turntable features a layered clamping structure with an inner support rod base and outer ring chucks, coupled with radially adjustable support rods to accommodate various brake drum specifications. The clamping force is even, preventing workpiece deformation. Dustproof plates on the chucks prevent laser slag from entering the transmission structure, reducing clamping failures. The crossbeam uses a double-sided gear and rack synchronous transmission, with a single crossbeam covering all stations. Each laser head module can independently achieve three-axis linkage, and the lead screw drives the vertical slide to achieve laser focal length adjustment. Real-time tracking ensures smooth inner walls and high dimensional consistency in the expanded holes; the eccentrically arranged rotary motor on the turntable makes full use of the internal space for compact multi-station layout, and the gear meshing transmission ensures smooth operation and eliminates cutting vibrations; the equipment is equipped with a central hollow mounting platform, an inclined material drop guide plate, and a waste material conveying platform, which can automatically collect and transfer cutting slag without the need for manual cleaning of the workstations; the whole machine is equipped with an external frame with a second-floor platform, and the upper level centrally houses supporting equipment such as water chillers and lasers, which greatly reduces the footprint; the fully enclosed sheet metal exterior, combined with independent dust collection boxes for each workstation, adsorbs cutting fumes at close range and isolates laser sparks, taking into account both the workshop environment and operational safety.

[0044] This processing method employs a non-contact laser hole enlargement process, eliminating radial cutting forces and tool wear issues. It removes multiple steps such as rough boring, semi-finish boring, and finish boring, forming the center hole in a single operation. This effectively shortens the processing time per piece and reduces tool consumables and equipment maintenance costs. The entire process relies on automated loading and unloading by a robotic arm, requiring no manual intervention. Before processing, multi-point capacitive edge calibration is used, acquiring the workpiece edge coordinates at least three times along different radial directions. The system automatically fits and calculates the true center, compensating for workpiece clamping eccentricity and accurately locking the processing datum. This significantly improves the roundness and concentricity of the brake drum center hole, enhancing subsequent wheel dynamic balance and overall vehicle braking performance. During processing, the chuck rotates at a uniform speed in conjunction with laser-guided cutting, ensuring high processing stability. Waste materials are automatically conveyed and circulated, resulting in a high degree of automation and enabling continuous cyclic batch production with lower overall processing costs.

[0045] The above description of the disclosed embodiments enables those skilled in the art to implement or use this patent. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this patent. Therefore, this patent is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A laser reaming machine for automotive brake drums, comprising a main body (01), characterized in that, The main body of the equipment (01) includes a base (1), on which multiple processing turntables (2) and laser processing devices are provided. The laser processing devices include a shaft drive system, on which multiple laser head modules (4) are installed. The number of laser head modules (4) corresponds to the number and position of the processing turntables (2). The machining turntable (2) includes a turntable base (2-1), on which a chuck (2-2) is rotatably mounted. The chuck (2-2) is provided with multiple jaws (2-3) and support rods (2-4). The multiple jaws (2-3) and multiple support rods (2-4) are distributed in a circular pattern, and the support rods (2-4) are located inside the circle of the jaws (2-3). The upper end of the support rods (2-4) is used to support the end face panel of the brake drum and is higher than the upper end of the jaws (2-3).

2. The laser reaming equipment for automotive brake drums according to claim 1, characterized in that, Multiple processing turntables (2) are arranged along a first direction. Laser head modules (4) are located on one side of the processing turntables (2) along a second direction and can be moved above the processing turntables (2). The first direction and the second direction are perpendicular to each other. The axial motion system includes a crossbeam (3). Along the first direction, the base (1) is provided with a first guide rail (5) and a first rack (6) on both sides. The first guide rail (5) and the first rack (6) are arranged along the second direction. The two ends of the crossbeam (3) are provided with crossbeam mounting seats (7). The crossbeam mounting seats (7) are slidably mounted on the first guide rail (5) on the corresponding side. The crossbeam mounting seats (7) are also provided with a crossbeam drive motor (8). The output shaft of the crossbeam drive motor (8) is provided with a first gear. The first gear meshes with the first rack (6) on the corresponding side. Multiple laser head modules (4) are mounted on the crossbeam (3).

3. The laser reaming equipment for automotive brake drums according to claim 2, characterized in that, The laser head module (4) includes a horizontal slide (4-1), a second rack (18) and a second guide rail (9) on the crossbeam (3), the horizontal slide (4-1) is movably mounted on the second guide rail (9), the horizontal slide (4-1) is provided with a module drive motor (4-6), the output shaft of the module drive motor (4-6) is equipped with a second gear, the second gear meshes with the second rack (18); the horizontal slide (4-1) is also equipped with a front extension beam (4-3), the front extension beam (4-3) is arranged along the second direction and extends towards the processing turntable (2), the end of the front extension beam (4-3) near the processing turntable (2) is equipped with a vertical slide (4-2) through a lead screw assembly (4-5), and the laser head body (4-4) is installed on the vertical slide (4-2).

4. The laser reaming equipment for automotive brake drums according to claim 1, characterized in that, The turntable base (2-1) is equipped with a rotary motor (2-5), which is eccentrically positioned relative to the rotation center of the chuck (2-2). A drive gear (2-6) is mounted on the output shaft of the rotary motor (2-5), and a driven gear (2-7) is provided at the lower part of the turntable base (2-1). The drive gear (2-6) meshes with the driven gear (2-7).

5. The laser reaming equipment for automotive brake drums according to claim 1, characterized in that, The upper end of the support rod (2-4) is machined with a threaded hole and an adjusting screw (2-11) is installed thereon. The lower end of the support rod (2-4) is provided with an adjusting plate (2-8). The adjusting plate (2-8) has an elongated hole (2-9) on it. The adjusting plate (2-8) is installed on the chuck (2-2) through the elongated hole (2-9). The elongated hole (2-9) is arranged radially along the chuck (2-2). The lower part of the jaw (2-3) is also provided with a dustproof plate (2-10). The dustproof plate (2-10) is in contact with the upper surface of the chuck (2-2).

6. The laser reaming equipment for automotive brake drums according to claim 1, characterized in that, It also includes a waste conveying platform (02), the conveying direction of the waste conveying platform (02) is set along the second direction, the receiving end of the waste conveying platform (02) extends into the base (1) and is located below the area where the processing turntable (2) is located, and the discharge end of the waste conveying platform (02) is provided with a waste hopper (17). The base (1) is provided with a mounting platform (10), and the processing turntable (2) is installed on the mounting platform (10). The middle part of the mounting platform (10) is hollowed out. At the bottom of the mounting platform (10), a material drop guide plate (11) is provided around the hollow window. The material drop guide plate (11) is inclined, and the lower end of the inclined surface faces the receiving end of the waste conveying platform (02). The upper surface of the material drop guide plate (11) is provided with a guide protrusion (12).

7. The laser reaming equipment for automotive brake drums according to claim 1, characterized in that, It also includes an external frame (03), which includes multiple columns (13), and a second-floor platform (14) is provided on the top of the columns (13). The main body of the equipment (01) is located in the space enclosed by the columns (13) and the second-floor platform (14). The supporting equipment of the main body of the equipment (01) is arranged on the second-floor platform (14). The base (1) is also provided with an outer sheet metal (15).

8. The laser reaming equipment for automotive brake drums according to claim 7, characterized in that, Inside the outer frame (03), the bottom surface of the second-floor platform (14) is provided with multiple dust removal boxes (16), the number of dust removal boxes (16) corresponds to the number of processing turntables (2), and the dust removal boxes (16) are located above the corresponding processing turntables (2).

9. A laser-reamed hole-reaming method for automotive brake drums, characterized in that, The laser reaming equipment for automotive brake drums as described in any one of claims 1-8 includes the following steps: S1. The loading and unloading equipment places several brake drums horizontally on the support rod (2-4) of the processing turntable (2), and the chuck (2-3) clamps and fixes the brake drums. S2. The crossbeam (3) drives each laser head module (4) to move above the processing turntable (2), and the vertical slide (4-2) descends, causing the laser head body (4-4) to descend to the processing position; S3. The chuck (2-2) rotates, and at the same time the laser head body (4-4) emits laser light for processing; S4. After processing is completed, the chuck (2-2) releases the brake drum, and the loading and unloading equipment removes the brake drum.

10. The laser reaming method for automotive brake drums according to claim 9, characterized in that, Step S2 includes: S2-1. The laser head body (4-4) is moved to the center position of the brake drum, and the nozzle is 0.5-1mm away from the workpiece surface; S2-2. The laser head body (4-4) moves radially outward along the brake drum. When it passes the edge of the inner hole of the brake drum, the capacitance sensor inside the laser head body (4-4) undergoes a capacitance jump. The coordinates of the laser head body (4-4) at this time are recorded. S2-3. Repeat step S2-2 at least three times, each time moving the laser head body (4-4) along a different radius of the brake drum; S2-4. Based on the coordinate information of the multiple laser head bodies (4-4) recorded in S2-3, recalibrate the center of the moving drum inner hole as the processing reference.

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