Automatic punching machining method for retro spoke automobile hub
By designing an automatic punching equipment and utilizing CNC computer control of multiple motors and pneumatic lifting bearings, the automated processing of retro spoked car wheel hubs has been achieved, solving the problems of low efficiency and safety hazards of manual operation, and realizing an efficient and safe production process.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-30
- Publication Date
- 2026-03-10
AI Technical Summary
Existing technology requires manual operation in the punching process of retro spoked car wheels, resulting in low production efficiency, high costs, and the risk of workplace accidents.
Design an automatic punching machine that uses a CNC computer to control a pneumatic lifting bearing, lifting motor, telescopic motor, servo motor, and push-pull motor to achieve an automated processing flow from loading to changing parts, including the coordinated work of the punching machine, fixture, mold base, and bottom mold.
Automated production has been achieved, which has improved production efficiency, reduced costs, eliminated workplace accidents, and ensured product quality and process simplicity.
Smart Images
Figure CN121624282A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the field of automobile parts manufacturing process, especially to an automatic punching processing method of a retro spoke automobile hub. BACKGROUND
[0002] The hub of modern automobile is mainly divided into aluminum alloy hub and steel hub, which is generally formed by pressure casting, and the steel hub is mostly formed by welding.
[0003] The spoke automobile hub was used in the last century due to the limitation of production level and manufacturing process, and it was connected with the rim and axle sleeve, which was shown in many successful and brilliant film and television works, and became the demand of many people in the market economy society. In order to improve production efficiency and reduce production cost, and at the same time guarantee product quality, an automatic intelligent processing equipment and processing method are designed and developed to avoid manual operation in the punching process of the spoke automobile hub, and to prevent the occurrence of work accidents. SUMMARY
[0004] The technical problem to be solved by the present application is to provide an automatic punching processing method of a retro spoke automobile hub, which is scientifically designed, and a pair of pneumatic lifting bearings are controlled by a numerical control computer to complete the feeding, a lifting motor is used to complete the lifting of the workbench, a telescopic motor is used to complete the telescopic movement of a servo motor, the servo motor is used to drive the clamp, and a push-pull motor is used to complete the push-pull movement of the die seat, so as to form a complete set of automatic intelligent punching process, achieve automatic processing from feeding to changing, save manual operation in the punching process, improve production efficiency, reduce production cost, guarantee product quality, prevent work accidents, and have the beneficial effects of standardized production, safety and efficiency, simple process, quality guarantee, and cost reduction.
[0005] The technical scheme adopted by the present application to solve the above technical problem is as follows: an automatic punching processing method of a retro spoke automobile hub, comprising an automatic punching equipment and an automatic punching processing method. The automatic punching equipment comprises a punch, a pair of pneumatic lifting bearings, a lifting motor, a workbench, a telescopic motor, a servo motor, a clamp, a push-pull motor, a die seat, a bottom die, a punch pin and a numerical control computer. The punch comprises a driving device, a punch head, a pair of vertical arms and a base, the base is symmetrically provided with a pair of vertical arms, the driving device is fixedly arranged on a pair of vertical arms, the driving device drives the punch head to reciprocate up and down in a pair of vertical arms to form punching, and the bottom surface of the punch head is connected with a punch pin through bolts. The lifting motor is fixedly installed in the reserved hole in the middle of the base, driving a lifting rod to rotate, which in turn drives the worktable, which is spirally sleeved on the upper part of the lifting rod, to move up and down along a pair of positioning rods. The telescopic motor is fixedly installed at the rear of the top surface of the workbench. The telescopic motor drives a slider that is movably installed in the open slide groove at the front of the top surface of the workbench to move horizontally left and right through the first rotating lead screw. A servo motor is fixedly mounted on the slider, and the servo motor moves horizontally back and forth synchronously with the slider; The front end of the servo motor is fixedly connected to the center of the turntable in the middle of the fixture via a connecting rod; The clamp includes a turntable and a collar in the middle. The inner ring of the collar is fitted onto the outer ring of the turntable by a ring of steel balls. Four buckles are regularly arranged at 90 degrees on the front of the collar. Each buckle is inserted into one of the four oblique slots regularly arranged at 90 degrees on the front of the turntable by a caster at the lower end of a long strip, forming a movable connection. The push-pull motor is fixedly mounted on the base platform at the other right end of the base. The push-pull motor pushes and pulls the mold seat back and forth in the slide groove provided in the middle of the base through the second lead screw. The mold base has a slanted notch at the lower front part of the fixture, and the top of the mold base is fixedly connected to the bottom mold by the bolts; The central hole of the sleeve fixedly installed on the top of the bottom mold is connected and permeable to the central hole of the bottom mold center and the chip removal hole of the upper part of the mold base. Each pair of pneumatic lifting bearings includes one identical pneumatic lifting bearing on each side. Each left pneumatic lifting bearing includes a left cylinder, a left lifting rod, and a left bearing located at the top of the left lifting rod. Each right pneumatic lifting bearing includes a right cylinder, a right lifting rod, and a right bearing located at the top of the right lifting rod. The pair of pneumatic lifting bearings are symmetrically arranged in a pair of holes pre-drilled in the base, respectively located on both sides of the sliding groove provided in the middle of the base.
[0006] The upper edges of the two sides of the groove in the middle of the base are symmetrically recessed, and a through chip leakage hole is provided at the bottom of the groove. The CNC computer is fixedly installed on the outside of one of the vertical arms of the stamping machine. The CNC computer is equipped with a central processing unit. The CNC computer is connected to the stamping machine, a pair of pneumatic lifting bearings, the lifting motor, the telescopic motor, the servo motor, and the push-pull motor through several data cables.
[0007] The automatic punching method of the automatic punching equipment: First, a car wheel hub to be punched slowly rolls from the left side of the conveying mechanism into the recess in the middle of the top surface of the base of the stamping press; Furthermore, the CNC computer commands the pneumatic lifting bearing to rise synchronously, pushing the car wheel hub against the turntable of the clamp to the concentric circle position of the collar; Furthermore, the CNC computer instructs the servo motor to rotate slowly clockwise, and the four inclined slots on the turntable rotate synchronously clockwise; Furthermore, the four casters at the lower ends of the four buckles slide synchronously downward in the four inclined slots, and pull the four buckles toward the center by their respective long strips, tightly locking one side rim of the car wheel hub. The turntable, the collar, and the car wheel hub are all locked together to form a whole. Furthermore, the CNC computer instructs the lifting motor to operate, raising the worktable to a set height; Furthermore, the CNC computer instructs the telescopic motor to operate, synchronously extending the slider and the servo motor to a set position; Furthermore, the CNC computer instructs the push-pull motor to operate, synchronously pushing the mold base and the bottom mold forward to the set position, where they are engaged in the car wheel hub; Furthermore, the CNC computer instructs the drive device of the stamping machine to work, and the stamping head drives the punch to press downwards, punching a hole in the rim of the car wheel hub. The debris generated by punching is discharged through the chip discharge hole in the sleeve, the bottom die, and the mold base. Furthermore, after a hole is punched, the CNC computer instructs the telescopic motor to drive the slider, the servo motor, the fixture, and the car wheel hub to move synchronously to the set position; Furthermore, the CNC computer instructs the servo motor to rotate clockwise to a set position to begin punching the next hole; this process is repeated to perform automatic punching according to the set program. Furthermore, after one round of holes is punched, the CNC computer instructs the lifting motor to raise or lower the worktable to a set position; the CNC computer instructs the telescopic motor to synchronously move the slider, the servo motor, the clamp, and the car wheel hub to a set position; and the second round of holes is punched. When the servo motor drives the clamp and the car wheel hub to rotate clockwise, the left and right bearings of the pair of pneumatic lifting bearings gently press against the outer ring surface of the car wheel hub to prevent the car wheel hub from sliding out of place due to inertia or sliding back to its original position, thus preventing displacement. Furthermore, once both rings of holes are punched, the CNC computer instructs the push-pull motor to pull the mold seat back completely detached from the car wheel hub; Furthermore, the CNC computer instructs the telescopic motor to drive the slider, the servo motor, and the fixture to move backward; Furthermore, the CNC computer instructs the servo motor to rotate slowly counterclockwise, and the turntable rotates slowly accordingly. The four inclined slots on the turntable drive each caster at the lower end of each strip to move obliquely upward relative to each other within the four inclined slots, pushing the four buckles outward and separating the car wheel hub from the clamp. Furthermore, the CNC computer commands a pair of pneumatic lifting bearings to slowly descend. When they are about to reach the bottom, the right pneumatic lifting bearing in the pair descends rapidly, and the car wheel hub slowly rolls away from the base to the right and enters the right-side conveyor mechanism. The conveyor mechanism on the left then slowly rolls into the next car wheel hub, and the CNC computer automatically repeats the above process to perform automatic punching production.
[0008] Compared with the prior art, the advantages of the present invention are as follows: The beneficial effects of this invention lie in its scientific design of an automatic punching process for retro-style spoked car wheel hubs. A pair of pneumatic lifting bearings, controlled by a CNC computer, complete the loading of the part. A lifting motor raises and lowers the worktable, a telescopic motor extends and retracts a servo motor, the servo motor drives the fixture, and a push-pull motor pushes and pulls the mold base, forming a complete automatic intelligent punching process. This achieves automated processing from loading to changing parts, eliminating manual operation in the punching process, improving production efficiency while reducing production costs, ensuring product quality while preventing workplace accidents. It offers the advantages of standardized procedures, automated production, safety and efficiency, simple processes, guaranteed quality, and significantly reduced costs. Attached Figure Description
[0009] Figure 1 This is a perspective view of the fixture assembly structure of the automatic punching equipment of the present invention; Figure 2 This is a front perspective view of the overall structure of the automatic punching device of the present invention; Figure 3 This is a side view of the longitudinal section of the automatic punching equipment of the present invention in its working state. Figure 4 This is a longitudinal sectional perspective view of the separated portion of the automatic punching device of the present invention. Figure 5 This is a side view of the overall structure of the automatic punching equipment of the present invention in its working state; Figure 6 This is a side view of the overall structure of the automatic punching device of the present invention in its separated state; Figure 7 for Figure 3 Enlarged perspective view of section A in the diagram; Figure 8 for Figure 4 Enlarged perspective view of section B in the diagram; Figure 9 for Figure 5 Enlarged schematic diagram of section C in the diagram; Figure 10 for Figure 6 An enlarged schematic diagram of the D section structure. Implementation
[0010] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments.
[0011] In this specific embodiment, such as Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 , Figure 8 , Figure 9 , Figure 10 As shown, an automatic punching method for retro spoked car wheel hubs includes an automatic punching device and an automatic punching method. The automatic punching equipment includes: a punching machine 1, a pair of pneumatic lifting bearings, a lifting motor 19, a worktable 22, a telescopic motor 35, a servo motor 32, a clamp, a push-pull motor 30, a mold base 29, a bottom mold 28, a punch 4, and a CNC computer 20. The stamping machine 1 includes a drive device, a stamping head 2, a pair of vertical arms 3, and a base 13. A pair of vertical arms 3 are symmetrically arranged on the base 13. The drive device is fixedly arranged on the pair of vertical arms 3. The drive device drives the stamping head 2 to reciprocate up and down in the pair of vertical arms 3 to form a stamping. A punch 4 is bolted to the bottom surface of the stamping head 2. The lifting motor 19 is fixedly installed in the reserved hole in the middle of the base 13, driving a lifting rod 38 to rotate, which in turn drives the worktable 22, which is spirally sleeved on the upper part of the lifting rod 38, to move up and down along a pair of positioning rods 37. The telescopic motor 35 is fixedly installed on the rear of the top surface of the workbench 22. The telescopic motor 35 drives a slider 33, which is movably installed in the front opening groove 36 of the top surface of the workbench 22, to move horizontally back and forth through the first rotating lead screw 34. A servo motor 32 is fixedly mounted on the slider 33, and the servo motor 32 moves horizontally back and forth synchronously with the slider 33; The front end of the servo motor 32 is fixedly connected to the center of the turntable 11 in the middle of the fixture via a connecting rod; The clamp includes the turntable 11 in the middle and the collar 5. The inner ring wall of the collar 5 is fitted onto the outer ring wall of the turntable 11 by a ring of steel balls 12. Four buckles 7 are regularly arranged at 90 degrees on the front of the collar 5. Each buckle 7 is inserted into one of the four oblique slots 8 regularly arranged at 90 degrees on the front of the turntable 11 by a caster 10 at the lower end of a long strip 9, forming a movable connection. The push-pull motor 30 is fixedly mounted on the base 31 at the other end of the base 13. The push-pull motor 30 pushes and pulls the mold seat 29 back and forth in the slide groove 17 provided in the middle of the base 13 through the second lead screw 40. The mold base 29 has a slanted notch at the lower front part of the fixture to allow the mold base 29 to avoid the car wheel hub 6. The top of the mold base 29 is fixedly connected to the bottom mold 28 by the bolts. The central hole of the sleeve 27 fixedly installed on the top of the bottom mold 28 is connected and permeable to the central hole of the bottom mold 28 and the chip removal hole 39 provided on the upper part of the mold base 29. Each pair of pneumatic lifting bearings includes one identical pneumatic lifting bearing on each side. The left pneumatic lifting bearing includes a left cylinder 16, a left lifting rod 15, and a left bearing 14 at the top of the left lifting rod 15. The right pneumatic lifting bearing includes a right cylinder 26, a right lifting rod 25, and a right bearing 24 at the top of the right lifting rod 25. The pair of pneumatic lifting bearings are symmetrically arranged in a pair of holes reserved in the base 13, respectively located on both sides of the sliding groove 17 provided in the middle of the base 13.
[0012] The upper edges of the sliding groove 17 in the middle of the base 13 are symmetrically arranged as a recess 23, and a through chip leakage hole 18 is provided at the bottom of the sliding groove 17. The CNC computer 20 is fixedly installed on the outside of one of the vertical arms 3 of the stamping machine. The CNC computer 20 is equipped with a central processing unit 21. The CNC computer 20 is connected to the stamping machine 1, a pair of pneumatic lifting bearings, the lifting motor 19, the telescopic motor 35, the servo motor 32, and the push-pull motor 30 through several data cables.
[0013] In this specific embodiment, such as Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 ,Figure 6 , Figure 7 , Figure 8 , Figure 9 , Figure 10 As shown, the automatic punching method of the automatic punching equipment is as follows: First, a car wheel hub 6 to be punched slowly rolls from the left side of the conveying mechanism into the recess 23 in the middle of the top surface of the base 13 of the stamping machine 1; Furthermore, the CNC computer 20 instructs the pneumatic lifting bearing to rise synchronously, so that the car wheel hub 6 is pushed against the turntable 11 of the clamp to the collar 5 in a concentric circle position; Furthermore, the CNC computer 20 instructs the servo motor 32 to rotate slowly clockwise, and the four inclined slots 8 on the turntable 11 rotate clockwise synchronously. Furthermore, the four casters 10 at the lower ends of the long strips 9 of the four buckles 7 slide down synchronously in the four inclined slots 8, and pull the four buckles 7 toward the center by their respective long strips 9, tightly locking one side rim of the car wheel hub 6, so that the turntable 11, the collar 5 and the car wheel hub 6 are locked together to form a whole. Furthermore, the CNC computer 20 instructs the lifting motor 19 to operate, raising the worktable 22 to a set height; Furthermore, the CNC computer 20 instructs the telescopic motor 35 to work, synchronously extending the slider 33 and the servo motor 32 to the set position; Furthermore, the CNC computer 20 instructs the push-pull motor 30 to work, synchronously pushing the mold base 29 and the bottom mold 28 forward to the set position and locking them into the car wheel hub 6; Furthermore, the CNC computer 20 instructs the drive device of the stamping machine 1 to work, and the stamping head 2 drives the punch 4 to punch downwards, punching a hole 41 on the rim of the car wheel hub 6. The debris generated by punching is discharged through the chip discharge hole 39 in the sleeve 4, the bottom die 28, and the die seat 29. Furthermore, after a hole 41 is punched, the CNC computer 20 instructs the telescopic motor 35 to drive the slider 33, the servo motor 32, the fixture, and the car wheel hub 6 to move synchronously to the set position; Furthermore, the CNC computer 20 instructs the servo motor 32 to rotate clockwise to a set position to start punching the next hole 41; this process is repeated to perform automatic punching according to the set program. Furthermore, after the first ring of holes 41 is punched, the CNC computer 20 instructs the lifting motor 19 to raise or lower the worktable 22 to a set position; the CNC computer 20 instructs the telescopic motor 35 to synchronously move the slider 33, the servo motor 32, the clamp, and the car wheel hub 6 to a set position; and the second ring of holes 41 is punched. When the servo motor 32 drives the clamp and the car wheel hub 6 to rotate clockwise, the left bearing 14 and the right bearing 24 of the pair of pneumatic lifting bearings gently press against the outer ring surface of the car wheel hub 6 to prevent the car wheel hub 6 from sliding out of place due to inertia or rotating back to its original position, thus preventing displacement. Furthermore, once both holes 41 are punched, the CNC computer 20 instructs the push-pull motor 30 to pull the mold base 29 back completely away from the car wheel hub 6; Furthermore, the CNC computer 20 instructs the telescopic motor 35 to drive the slider 33, the servo motor 32, and the fixture to move backward; Furthermore, the CNC computer 20 instructs the servo motor 32 to rotate slowly counterclockwise, and the turntable 11 rotates slowly accordingly. The four inclined slots 8 on the turntable 11 drive each caster 10 at the lower end of each strip 9 to move obliquely upward relative to each other within the four inclined slots 8, pushing the four buckles 7 outward and separating the car wheel hub 6 from the clamp. Furthermore, the CNC computer 20 instructs a pair of pneumatic lifting bearings to slowly descend. When they are about to reach the bottom, the right pneumatic lifting bearing in the pair descends rapidly, and the car wheel hub 6 slowly rolls away from the base 13 to the right and enters the right-side conveyor mechanism. The left-hand conveyor then slowly rolls into the next car wheel hub 6, and the CNC computer 20 automatically repeats the above process to perform automatic punching production.
[0014] Compared with the prior art, the advantages of the present invention are as follows: The beneficial effects of this invention lie in its scientific design of an automatic punching process for retro-style spoked car wheel hubs. A pair of pneumatic lifting bearings, controlled by a CNC computer, complete the loading of the part. A lifting motor raises and lowers the worktable, a telescopic motor extends and retracts a servo motor, the servo motor drives the fixture, and a push-pull motor pushes and pulls the mold base, forming a complete automatic intelligent punching process. This achieves automated processing from loading to changing parts, eliminating manual operation in the punching process, improving production efficiency while reducing production costs, ensuring product quality while preventing workplace accidents. It offers the advantages of standardized procedures, automated production, safety and efficiency, simple processes, guaranteed quality, and significantly reduced costs.
[0015] Finally, it should be noted that the specific embodiments described herein are merely illustrative of the spirit of the invention and are not intended to limit the implementation of the invention. Those skilled in the art can make various modifications or additions to the described embodiments or use similar methods to replace them; it is neither necessary nor possible to exemplify all embodiments here. However, these obvious variations or modifications derived from the essential spirit of the invention still fall within the scope of protection of the invention, and interpreting them as any additional limitation would contradict the spirit of the invention.
Claims
1. An automatic punching method for retro-style spoked car wheel hubs, characterized in that: The application relates to an automatic punching device and an automatic punching method. The automatic punching device comprises a punch press, a pair of pneumatic lifting bearings, a lifting motor, a workbench, an extension motor, a servo motor, a clamp, a push-pull motor, a die holder, a bottom die, a punch pin and a numerical control computer. The punch press comprises a driving device, a punch head, a pair of vertical arms, and a base, the base is symmetrically provided with the pair of vertical arms, the driving device is fixedly arranged on the pair of vertical arms, the driving device drives the punch head to reciprocate up and down in the pair of vertical arms to form a punch, and the punch head bottom surface is provided with the punch pin through bolt connection. The lifting motor is fixedly arranged in a reserved hole arranged in the middle of the base, drives a lifting rod to rotate, and drives the workbench provided with a screw sleeve on the upper part of the lifting rod to move up and down along a pair of positioning rods. The extension motor is fixedly arranged on the top surface of the workbench, drives a sliding block movably arranged in an opening sliding groove arranged on the front part of the top surface of the workbench to move left and right horizontally through a first rotating screw rod. A servo motor is fixedly arranged on the sliding block, and the servo motor moves forward and backward horizontally synchronously with the sliding block. The front end of the servo motor is fixedly connected with the center of a rotating disc arranged in the middle of the clamp through a connecting rod. The clamp comprises the rotating disc arranged in the middle and a sleeve ring, the inner wall of the sleeve ring is provided with a steel ball through a ring, the front surface of the sleeve ring is regularly provided with four buckles at an angle of 90 degrees, each buckle is inserted into four oblique insertion grooves regularly arranged at an angle of 90 degrees on the front surface of the rotating disc through a long strip end wheel, and the sleeve ring is movably connected with the rotating disc. The push-pull motor is fixedly arranged on a base arranged at the other right end of the base, and the push-pull motor drives the die holder to move forward and backward in a sliding groove arranged in the middle of the base through a second screw rod. The die holder is provided with an oblique notch in the front middle and lower part of the clamp, and the top of the die holder is fixedly connected with the bottom die through the bolt. The middle hole of the sleeve pipe fixedly arranged on the top of the bottom die is connected with the center hole arranged in the center of the bottom die and the chip removal hole arranged on the upper part of the die holder. The pair of pneumatic lifting bearings comprises two completely same pneumatic lifting bearings, each left pneumatic lifting bearing comprises a left cylinder, a left lifting rod and a left bearing arranged on the top end of the left lifting rod, and each right pneumatic lifting bearing comprises a right cylinder, a right lifting rod and a right bearing arranged on the top end of the right lifting rod. The pair of pneumatic lifting bearings are symmetrically arranged in a pair of holes reserved in the base and located on the two sides of the sliding groove arranged in the middle of the base.
2. The two upper openings of the sliding groove arranged in the middle of the base are symmetrically arranged into a recess, and a through chip removal hole is arranged on the bottom of the sliding groove. The numerical control computer is fixedly arranged outside one vertical arm of the punch press, a central processing unit is arranged in the numerical control computer, and the numerical control computer is connected with the punch press, the pair of pneumatic lifting bearings, the lifting motor, the extension motor, the servo motor and the push-pull motor through a plurality of data lines.
3. The automatic punching processing method of the retro spoke automobile wheel hub according to claim 1, characterized in that: The automatic punching method of the automatic punching device: First, a to be punched automobile hub slowly rolls from the left on the conveying mechanism into the recess in the middle of the top surface of the base of the punch press; Further, the numerical control computer instruction synchronously raises the pneumatic lifting bearings, and the automobile hub is lifted to the concentric position with the sleeve ring against the rotating disc of the clamp; Further, the numerical control computer instruction slowly rotates the servo motor clockwise, and the four inclined slots on the rotating disc synchronously rotate clockwise; Further, the four casters at the lower ends of the four clamps synchronously slide downward in the four inclined slots, and the four clamps are retracted to the center by pulling the respective long strips, tightly clamping and blocking one side of the automobile hub, and the rotating disc, the sleeve ring and the automobile hub are clamped to form an integral whole; Further, the numerical control computer instruction operates the lifting motor to lift the workbench to a set height; Further, the numerical control computer instruction operates the telescopic motor to synchronously extend the slider and the servo motor to a set position; Further, the numerical control computer instruction operates the push-pull motor to synchronously push the die holder and the bottom die to a set position and clamp into the automobile hub; Further, the numerical control computer instruction operates the driving device of the punch press, and the punch head drives the punch pin to punch downward to punch a hole on the rim of the automobile hub, and the debris generated by punching is discharged through the drain hole in the sleeve, the bottom die and the die holder; Further, the numerical control computer instruction synchronously moves the slider, the servo motor, the clamp and the automobile hub to a set position by operating the telescopic motor; Further, the numerical control computer instruction rotates the servo motor clockwise to a set position to start punching the next hole; the above process is repeated according to the set program to automatically punch holes; Further, when a circle of holes is punched, the numerical control computer instruction lifts or lowers the workbench to a set position by operating the lifting motor, and synchronously moves the slider, the servo motor, the clamp and the automobile hub to a set position by operating the telescopic motor to start punching the second circle of holes; When the rotating disc and the automobile hub are rotated clockwise by the servo motor, the left bearing and the right bearing of the pair of pneumatic lifting bearings are lightly pressed against the outer surface of the automobile hub to prevent the automobile hub from sliding out of position or rotating back to the original position, thereby preventing displacement; Further, when two circles of holes are punched, the numerical control computer instruction operates the push-pull motor to pull the die holder backward to completely separate from the automobile hub; Further, the numerical control computer instruction drives the slider, the servo motor and the clamp backward by operating the telescopic motor; Further, the numerical control computer instructs the servo motor to rotate slowly counterclockwise, the rotating disc follows to rotate slowly, the four inclined slots on the rotating disc drive each caster at the lower end of each long strip to move relatively obliquely upward in the four inclined slots, four buckles are pushed outward, and the automobile hub is separated from the clamp; Further, the numerical control computer instructs a pair of pneumatic lifting bearings to slowly descend, when descending to the bottom, the right pneumatic lifting bearing in the pair of pneumatic lifting bearings quickly descends, the automobile hub slowly rolls away from the base to the right into the right conveying mechanism; The left conveying mechanism slowly rolls into the next automobile hub, and the numerical control computer automatically repeats the above process to automatically punch.