Semi-hollow rivet non-prepunching rotary feeding riveting device for automobile safety belt shaft and riveting process thereof

Abstract

The application relates to the technical field of rotary riveting, in particular to a semi-hollow rivet pre-punching-free rotary feeding riveting device for an automobile safety belt shaft and a riveting process thereof, which comprises a rack, a supporting table and a switching disc arranged on the rack, a plurality of groups of magnetic attraction driving heads with different specifications arranged on the switching disc, the magnetic attraction driving heads being capable of being actively rotated when the magnetic attraction driving heads are switched to operation stations, a coupling shaft coaxially connected with the switching disc, a locking disc installed on the coupling shaft, a plurality of groups of locking grooves arranged on the locking disc, and an inclined guide surface connected to the end of the locking groove, a lifting frame arranged on the rack, an elastic locking structure arranged on the lifting frame, the elastic locking structure being matched with the locking groove and capable of axially locking the switching disc, a driving assembly installed on the rack, the driving assembly being capable of rotating the coupling shaft after driving the elastic locking structure to be separated from the locking disc, and the inclined guide surface being capable of guiding the elastic locking structure to enter the locking groove when the driving assembly rotates by a predetermined angle, so that the riveting efficiency is improved.

Description

Technical Field

[0001] This invention relates to the field of rotary riveting technology, specifically to a rotary feed riveting device and riveting process for a semi-hollow rivet without pre-drilled holes for a car seat belt spindle. Background Technology

[0002] In the manufacturing process of automotive seat belt spindles, the riveting of the spindle and the connecting parts is one of the key processes. Semi-hollow rivet without pre-drilled holes rotary feed riveting technology is an advanced connection process. By using the high-speed rotation and axial feed of the rivet, frictional heat is used to soften the material, achieving a high-quality connection without pre-drilled holes. It has significant advantages in the field of seat belt spindle assembly.

[0003] However, in actual production, automotive seat belt spindles often correspond to various specifications of connectors. These connectors differ in thickness, material, and structure, necessitating the use of semi-hollow rivets of different sizes or specifications during riveting. Therefore, during the riveting process, it is necessary to switch the drive head that matches the rivet according to the working conditions.

[0004] Currently, drive head switching methods are mainly divided into two categories: manual replacement and axial cyclic switching. Manual replacement is cumbersome, and the drive head must be recalibrated after replacement to ensure that its rotation axis is perpendicular to the workpiece surface. If the calibration is not done properly, the drive head is prone to vibration when rotating at high speed, which may cause rivets to fall off or the riveting angle to deviate, directly affecting the riveting quality and consistency.

[0005] The axial cyclic switching method involves mounting multiple drive heads on a switching disc, with a self-locking motor driving the disc's rotation to switch the drive heads. While this method improves switching efficiency, it still has inherent drawbacks: Firstly, the self-locking motor itself has angular control errors, making it difficult to guarantee precise switching each time; secondly, there are mechanical clearances within the self-locking mechanism, causing a slight amount of wobble in the switched disc even when locked. The combination of these two factors can easily cause a slight misalignment of the drive head axis relative to the theoretical vertical direction after switching, making it impossible to guarantee the strict perpendicularity between the rivet and the connecting part. More importantly, during riveting, the drive head is subjected to significant axial reaction force and torque. The clearances in the switching mechanism can cause instantaneous displacement or vibration of the drive head, weakening the connection stability between the drive head and the rivet, thus affecting the rivet's screwing trajectory and forming quality, and in severe cases, even leading to riveting failure. Summary of the Invention

[0006] The purpose of this invention is to provide a riveting device and riveting process for a semi-hollow rivet without pre-drilled holes for automotive seat belt spindles, in order to solve the problems mentioned in the background art.

[0007] To achieve the above objectives, the present invention provides the following technical solution: A rotary feed riveting device for semi-hollow rivets without pre-drilled holes on automotive seat belt spindles, comprising: The frame is equipped with a support platform and a switching plate. The switching plate is equipped with multiple sets of magnetic drive heads of different specifications. When the magnetic drive head is switched to the working position, it can rotate actively. A coupling is coaxially connected to the switching disk. A locking disc is installed on the coupling. The locking disc is provided with multiple sets of locking grooves. An inclined guide surface is connected to the end of the locking groove. A lifting frame is mounted on the machine frame. The lifting frame is equipped with an elastic locking structure. The elastic locking structure cooperates with the locking groove to lock the switching disc axially. A drive assembly is mounted on the frame. The drive assembly can drive the coupling to rotate after the elastic locking structure is separated from the locking disc. When the drive assembly rotates at a predetermined angle, the inclined guide surface can guide the elastic locking structure into the locking groove.

[0008] The semi-hollow rivet riveting device for the automotive seat belt spindle without pre-drilled holes, as described above, has an annular groove on the switching disc, which rolls in cooperation with multiple sets of limit wheels rotatably mounted on the lifting frame.

[0009] The semi-hollow rivet without pre-drilled holes rotary feed riveting device for the automotive seat belt spindle as described above: the elastic locking structure includes a bracket mounted on the lifting frame and a horizontal shaft set on the bracket. The bracket is provided with a shaft shifting member coaxial with the coupling. The shaft shifting member is slidably connected to the horizontal shaft. A first columnar spring is sleeved on the horizontal shaft. The first columnar spring is connected to the shaft shifting member. A second convex shaft is provided on the outer side of the shaft shifting component, and the second convex shaft is adapted to the locking groove; The shaft shifting component has a protrusion inside, which abuts and is adapted to the third convex shaft provided on the drive assembly.

[0010] The semi-hollow rivet without pre-drilled holes rotary feed riveting device for the automotive seat belt spindle as described above: the protrusion protrudes towards the center of the shaft moving part and forms a first helical surface, an arc-shaped surface and a second helical surface; The first helical surface engages with the third convex shaft, which can drive the second convex shaft away from the locking groove. The second helical surface engages with the third convex shaft, enabling the second convex shaft to move toward the locking groove.

[0011] The semi-hollow rivet riveting device for automotive seat belt spindle without pre-drilled holes as described above: the drive assembly includes a second drive motor mounted on the bracket, a drive shaft connected to the output shaft of the second drive motor, and the drive shaft connected to the coupling via a sliding key structure; The drive assembly also includes a follower ring coaxially connected to the drive shaft, and the third convex shaft is disposed on the follower ring.

[0012] The semi-hollow rivet riveting device for automotive seat belt spindles without pre-drilled holes, as described above, has the following internal structure: the coupling is hollow, and the sliding key structure includes a first convex shaft disposed on the drive shaft and an arc-shaped groove disposed on the coupling, wherein the first convex shaft can slide within the arc-shaped groove.

[0013] The semi-hollow rivet without pre-drilled holes rotary feed riveting device for the automotive seat belt spindle as described above: multiple sets of electric telescopic rods are provided on the support platform, and a pressure member is connected to the actuating end of the electric telescopic rod. One end of the pressure member is provided with a pressing part, and the other end is provided with a guide shaft. The guide shaft is slidably connected to the support platform. The pressure-applying component is also provided with a pre-pressure structure. When the pressure-applying component moves toward the workpiece, the pre-pressure structure and the pressing part abut against the workpiece in sequence.

[0014] The semi-hollow rivet riveting device for automotive seat belt spindles without pre-drilled holes as described above: the pre-pressure structure includes a pre-pressure rod that slides through the pressure-applying component, and a second columnar spring is sleeved on the pre-pressure rod. The second columnar spring connects the end of the pre-pressure rod and the pressure-applying component.

[0015] The riveting process using the semi-hollow rivet without pre-drilled holes rotary feed riveting device for the automotive seat belt mandrel includes the following steps: Step 1: Place the car seat belt spindle and connector to be riveted on the support platform, and start the electric telescopic rod to make the pre-compression structure and the lower pressure part abut against the connector; Step 2: Control the operation of the drive component according to production needs. First, release the elastic locking structure from locking the switching disk, and then drive the coupling to rotate, so that the corresponding magnetic drive head can be switched to the working position. Step 3: Place the rivet of the corresponding specification on the magnetic drive head, and then control the magnetic drive head to rotate; Step 4: The lifting frame moves toward the support platform until the rivet abuts against the connector. The friction between the two generates heat, causing the rivet to pass through the connector and partially enter the spindle of the car seat belt. Step 5: Control the magnetic drive head to stop rotating, and at the same time, the lifting frame further descends, pressing down on the rivet, causing the lower end of the rivet to expand and deform inside the spindle of the car seat belt.

[0016] Compared with the prior art, the beneficial effects of the present invention are: By incorporating annular grooves, limiting wheels, locking discs, and elastic locking structures, the magnetic drive head first maintains a strictly perpendicular relationship with the coupling in the X direction when it switches to the working position (i.e., it is vertical in the X direction). This effectively prevents bending torque on the coupling caused by the upward reaction force on the magnetic drive head during riveting, thus ensuring the vertical accuracy of riveting and the long-term stability of the structure. Secondly, when the magnetic drive head switches to the working position, the coupling and switching disc are in an axially locked state. In this state, the axis of the magnetic drive head remains vertical in the Y direction. The precise constraints in both directions ensure that the magnetic drive head maintains a vertical posture throughout the riveting process, effectively preventing tilting or deflection due to force reaction when rotating towards the connector and the car seat belt spindle. This ensures the perpendicularity requirements between the rivet and the workpiece, improves the stability and quality of the riveting process, and enhances the connection strength and consistency. The elastic locking structure and drive components allow the coupling and switching disc to be unlocked before rotation, effectively preventing motion interference. Furthermore, the inclined guide surface guides the second convex shaft to automatically slide into the locking groove when the second drive motor rotates to a preset angle, ensuring precise entry of the second convex shaft into the locking groove. This guarantees the perpendicularity accuracy of the magnetic drive head in the Y direction after switching, preventing positional deviations caused by errors in the rotation angle of the second drive motor, and further ensuring the perpendicularity of the magnetic drive head. Attached Figure Description

[0017] Figure 1 A schematic diagram of a rotary feed riveting device for a semi-hollow rivet without pre-drilled holes for a car seat belt spindle.

[0018] Figure 2 This is a schematic diagram of the structure of a rotary feed riveting device for semi-hollow rivets without pre-drilled holes in automotive seat belt spindles after the frame and support platform have been removed.

[0019] Figure 3 for Figure 2 Enlarged view of the structure at point A in the middle.

[0020] Figure 4 This is a schematic diagram of the structure of a semi-hollow rivet without pre-drilled holes in a rotary feed riveting device for automotive seat belt spindles, taken from another angle after the frame and support platform have been removed.

[0021] Figure 5 Exploded view of the switching disc, coupling, lifting frame, and drive assembly in a rotary feed riveting device for semi-hollow rivets without pre-drilled holes for automotive seat belt spindles.

[0022] Figure 6A schematic diagram of the coupling and locking disc in a rotary feed riveting device for a semi-hollow rivet without pre-drilled holes, used for automotive seat belt spindles.

[0023] Figure 7 An exploded view of the elastic locking structure in a rotary feed riveting device for a semi-hollow rivet without pre-drilled holes, used for automotive seat belt spindles.

[0024] Figure 8 This is a structural diagram of the support platform, electric telescopic rod, pressure application component, and pre-pressure structure in a rotary feed riveting device for semi-hollow rivets without pre-drilled holes for automotive seat belt spindles.

[0025] Figure 9 Exploded view of the electric telescopic rod, pressure application component, and pre-compression structure in a rotary feed riveting device for a semi-hollow rivet without pre-drilled holes for a car seat belt spindle.

[0026] In the diagram: 1. Frame; 2. Support platform; 3. Lifting frame; 4. Switching disc; 401. Annular groove; 5. Magnetic drive head; 6. First gear; 7. Second gear; 8. First drive motor; 9. Limiting wheel; 10. Bracket; 11. Second drive motor; 12. Drive shaft; 1201. First convex shaft; 13. Coupling; 1301. Arc groove; 14. Locking disc; 1401. Locking groove; 1402. Inclined guide surface; 15. Shaft shifting component; 1501. Second convex shaft; 1502. First helical surface; 1503. Arc surface; 1504. Second helical surface; 16. Horizontal shaft; 17. First cylindrical spring; 18. Follower ring; 1801. Third convex shaft; 19. Electric telescopic rod; 20. Pressure application component; 21. Guide shaft; 22. Lowering part; 23. Preload rod; 24. Second cylindrical spring. Detailed Implementation

[0027] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0028] Please see Figures 1-9 As an embodiment of the present invention, the semi-hollow rivet riveting device for the automotive seat belt spindle without pre-drilled holes includes: a frame 1, a coupling 13, a lifting frame 3, and a drive assembly.

[0029] The frame 1 is provided with a support platform 2 and a switching disk 4. The switching disk 4 is provided with multiple sets of magnetic drive heads 5 of different specifications. When the magnetic drive head 5 is switched to the working position, it can rotate actively. Specifically, the magnetic drive head 5 is rotatably mounted on the switching disk 4, and one end of the magnetic drive head 5 is provided with a first gear 6. The lifting frame 3 is equipped with a first drive motor 8, and the output shaft of the first drive motor 8 is connected to a second gear 7. The second gear 7 is adapted to the first gear 6.

[0030] In this embodiment, the switching disk 4 can rotate relative to the lifting frame 3. During use, by driving the switching disk 4 to rotate, the spatial position of each set of magnetic drive heads 5 mounted on it can be changed. When any set of magnetic drive heads 5 rotates to a vertically downward position, it switches to the working position. In this state, the first gear 6 connected to that set of magnetic drive heads 5 meshes with the second gear 7. At this time, the first drive motor 8 is started, and power is transmitted to the corresponding magnetic drive head 5 through the meshing first gear 6 and second gear 7, driving it to rotate, thereby causing the rivets mounted on that set of magnetic drive heads 5 to rotate at high speed, performing the riveting operation.

[0031] Compared to the existing technology that configures an independent drive source for each set of magnetic drive heads 5, this application uses a single drive source. First, by using a single drive source combined with gear switching, the number of drive motors is significantly reduced, simplifying the overall structure and electrical control system, and reducing equipment manufacturing costs and control complexity. Second, the reduction in the number of drive sources effectively reduces the rotational inertia of the switching disk 4 during rotation, resulting in a smaller drive load on the switching disk 4. This not only reduces the requirements for the output capacity of the drive components but also reduces the mechanical impact caused by inertia when switching to the correct position, improving the smoothness and positioning accuracy of the workstation switching, thereby enhancing the long-term reliability and service life of the equipment.

[0032] It should be noted that the magnetic drive head 5 has a truncated quadrangular cavity at its end, while the top of the rivet has a truncated quadrangular protrusion. The truncated quadrangular protrusion and the truncated quadrangular cavity are matched to achieve automatic centering and positioning when the rivet is loaded onto the magnetic drive head 5, preventing the two from shaking during rotation. At the same time, the cooperation between the truncated quadrangular protrusion and the truncated quadrangular cavity can achieve stable torque transmission, ensuring that the rivet and the magnetic drive head 5 can rotate stably and synchronously.

[0033] Please see Figures 5-6 The coupling 13 is coaxially connected to the switching disk 4. A locking disk 14 is installed on the coupling 13. The locking disk 14 is provided with multiple sets of locking grooves 1401. An inclined guide surface 1402 is connected to the end of the locking groove 1401. The switching disk 4 is provided with an annular groove 401, which is in rolling cooperation with multiple sets of limit wheels 9 rotatably mounted on the lifting frame 3.

[0034] To facilitate a clear description of spatial orientation, the following definitions apply: the X direction is the direction passing through the central axis of coupling 13 and perpendicular to the horizontal plane, and the Y direction is the direction perpendicular to the central axis of coupling 13 and parallel to the vertical plane.

[0035] When the magnetic drive head 5 in the working position is vertical in both the X and Y directions, and the car seat belt spindle and connector are placed horizontally, it can ensure that the rivet acts on the car seat belt spindle and connector in an attitude perpendicular to the workpiece surface, thus meeting the strict requirements of the riveting process for perpendicularity.

[0036] During the rotation of the switching disk 4 driven by the coupling 13, the limiting wheel 9 always maintains rolling contact with the annular groove 401, and the side of the limiting wheel 9 also maintains contact with the side of the annular groove 401. Under this constraint, the switching disk 4 can always maintain an attitude parallel to the Y direction. Therefore, when the magnetic drive head 5 switches to the working position, its axis maintains a strict perpendicular relationship with the coupling 13 in the X direction (i.e., it is vertical in the X direction), effectively avoiding the bending moment generated on the coupling 13 due to the upward reaction force on the magnetic drive head 5 during the riveting process, thus ensuring the vertical accuracy of the riveting and the long-term stability of the structure.

[0037] Please see Figures 4-5 , Figure 7 The lifting frame 3 is mounted on the frame 1, and the lifting frame 3 is provided with an elastic locking structure. The elastic locking structure cooperates with the locking groove 1401 to lock the switching disk 4 axially. In this embodiment, when the elastic locking structure is embedded in the locking groove 1401, the coupling 13 and the switching disk 4 are in an axially locked state. In this state, after the magnetic drive head 5 switches to the working position, its axis remains vertical in both the X and Y directions, thus achieving strict vertical locking in both directions.

[0038] This locking state ensures that the magnetic drive head 5 remains vertical during the riveting process, effectively preventing tilting or deflection due to force reaction when rotating towards the connector and the car seat belt spindle. This ensures the perpendicularity requirement between the rivet and the workpiece, improves the stability and quality of the riveting process, and enhances the connection strength and consistency.

[0039] Specifically, the elastic locking structure includes a bracket 10 mounted on the lifting frame 3 and a horizontal shaft 16 disposed on the bracket 10. The bracket 10 is provided with a shaft shifting member 15 coaxial with the coupling 13. The shaft shifting member 15 is slidably connected to the horizontal shaft 16. A first columnar spring 17 is sleeved on the horizontal shaft 16. The first columnar spring 17 is connected to the shaft shifting member 15. A second convex shaft 1501 is provided on the outer side of the shaft shifting member 15, and the second convex shaft 1501 is adapted to the locking groove 1401. The shaft shifting member 15 has a protrusion inside, which abuts and is adapted to the third convex shaft 1801 provided on the drive assembly.

[0040] In the initial state, the first cylindrical spring 17 is in its natural state, and the second convex shaft 1501 is located within the locking groove 1401 (the second convex shaft 1501 does not abut against the end of the locking groove 1401). At this time, the second convex shaft 1501 and the locking groove 1401 cooperate to lock the coupling shaft 13, so that when the switching disk 4 rotates to change the spatial position of the corresponding magnetic drive head 5, the magnetic drive head 5 in the working position can be in a vertical state in both the X and Y directions, ensuring that the magnetic drive head 5 can be stably perpendicular to the connector and the car seat belt spindle.

[0041] Please see Figure 7 The protrusion protrudes toward the center of the shaft shifter 15 and forms a first helical surface 1502, an arc-shaped surface 1503 and a second helical surface 1504; The first spiral surface 1502 cooperates with the third convex shaft 1801, which can drive the second convex shaft 1501 away from the locking groove 1401. The second helical surface 1504 engages with the third convex shaft 1801, enabling the second convex shaft 1501 to move toward the locking groove 1401.

[0042] During the riveting process, when it is necessary to switch between different rivet specifications and change the spatial position of the magnetic drive head 5, the drive assembly starts to operate. At this time, the third cam shaft 1801 on the drive assembly acts on the first helical surface 1502, driving the second cam shaft 1501 to move away from the locking disc 14. As the third cam shaft 1801 rotates further, the second cam shaft 1501 gradually moves onto the arc-shaped surface 1503, thereby achieving complete separation of the second cam shaft 1501 from the locking disc 14.

[0043] Based on the above settings, the locking state of the locking disc 14 can be released in advance before the drive component drives the coupling 13 to rotate, effectively avoiding locking or interference caused by the locking disc 14 still being locked, ensuring the smoothness and reliability of the workstation switching process, and thus improving the stability and safety of equipment operation.

[0044] It should also be noted that a damping sleeve is provided at the rotating connection between the coupling 13 and the lifting frame 3. The damping sleeve can provide a certain rotational resistance to the coupling 13 to prevent it from rotating freely after the axial lock of the coupling 13 is released, which would cause the switching of the magnetic drive head 5 to be disordered.

[0045] Please see Figures 4-5 , Figure 7 The drive assembly is mounted on the frame 1. The drive assembly can drive the coupling 13 to rotate after the elastic locking structure is separated from the locking disc 14. When the drive assembly rotates at a predetermined angle, the inclined guide surface 1402 can guide the elastic locking structure into the locking groove 1401. The drive assembly includes a second drive motor 11 mounted on the bracket 10, and a drive shaft 12 is connected to the output shaft of the second drive motor 11. The drive shaft 12 is connected to the coupling 13 via a keyway structure. The drive assembly also includes a follower ring 18 coaxially connected to the drive shaft 12, and the third convex shaft 1801 is disposed on the follower ring 18; The coupling 13 has a hollow interior. The sliding key structure includes a first convex shaft 1201 on the drive shaft 12 and an arc groove 1301 on the coupling 13. The first convex shaft 1201 can slide within the arc groove 1301.

[0046] In this embodiment, initially, the third convex shaft 1801 is separated from the first helical surface 1502, and the first convex shaft 1201 is located at the end of the arc-shaped groove 1301 away from its direction of movement. When the drive shaft 12 starts to rotate, the third convex shaft 1801 first engages with the first helical surface 1502. During this engagement, the first convex shaft 1201 slides within the arc-shaped groove 1301 and has not yet engaged with the other end of the arc-shaped groove 1301. At this time, the third convex shaft 1801 moves in a circular motion with the drive shaft 12, and through its engagement with the first helical surface 1502, it drives the second convex shaft 1501 to gradually separate from the locking groove 1401. During this unlocking process, the coupling 13 has not yet rotated due to the rotation of the drive shaft 12, thus effectively avoiding motion interference.

[0047] When the third convex shaft 1801 moves onto the arc-shaped surface 1503, the second convex shaft 1501 has completely disengaged from the locking groove 1401. At this time, the first convex shaft 1201 just abuts against the other end of the arc-shaped groove 1301, and the coupling 13 begins to rotate synchronously with the drive shaft 12. After rotating to a predetermined angle, the third convex shaft 1801 separates from the arc-shaped surface 1503. Under the action of the first columnar spring 17, the shaft shifting member 15 moves towards the locking disc 14 until the second convex shaft 1501 abuts against the side of the locking disc 14. When the second drive motor 11 rotates to a preset angle, the second convex shaft 1501 enters the corresponding inclined guide surface 1402. Under the guidance of the inclined guide surface 1402, the second convex shaft 1501 automatically slides into the locking groove 1401. This structure can effectively compensate for the angular deviation that may occur during the rotation of the second drive motor 11, ensuring that the second convex shaft 1501 accurately enters the locking groove 1401, thereby ensuring the perpendicularity accuracy of the magnetic drive head 5 in the Y direction after switching.

[0048] In addition, the second drive motor 11 has a built-in torque sensor. When the second drive motor 11 rotates excessively due to rotational error, after the second cam 1501 enters the locking groove 1401, if the second drive motor 11 continues to rotate, the torque sensor detects an abnormal increase in output torque and immediately controls the second drive motor 11 to stop, preventing damage to the motor due to overload.

[0049] Furthermore, after the second convex shaft 1501 enters the locking groove 1401, the coupling 13 and the switching disk 4 are again axially locked, ensuring that the magnetic drive head 5 in the working position always maintains a perpendicular posture to the connector and the car seat belt spindle. To facilitate subsequent position switching, the second drive motor 11 needs to rotate in the opposite direction. During this process, the third convex shaft 1801 rotates in the opposite direction and abuts against the second helical surface 1504, and the drive shaft moving part 15 moves further toward the locking groove 1401. During this process, the coupling 13 and the switching disk 4 can still be locked. After the third convex shaft 1801 is fully reset, the third convex shaft 1801 separates from the protrusion and returns to the initial state. At the same time, the relative position of the first convex shaft 1201 and the arc groove 1301 also returns to the initial state. Thus, the device provides an accurate position reference for the next switching action, ensuring that the magnetic drive head 5 can achieve continuous and stable cyclic switching.

[0050] Please see Figure 1 , Figures 8-9 The support platform 2 is provided with multiple sets of electric telescopic rods 19. The actuating end of the electric telescopic rod 19 is connected to a pressure member 20. One end of the pressure member 20 is provided with a pressing part 22, and the other end is provided with a guide shaft 21. The guide shaft 21 is slidably connected to the support platform 2. The pressure-applying component 20 is also provided with a pre-pressure structure. When the pressure-applying component 20 moves toward the workpiece, the pre-pressure structure and the pressing part 22 abut against the workpiece in sequence. The pre-pressure structure includes a pre-pressure rod 23 that slides through the pressure-applying component 20. A second columnar spring 24 is sleeved on the pre-pressure rod 23. The second columnar spring 24 connects the end of the pre-pressure rod 23 and the pressure-applying component 20.

[0051] In this embodiment, initially, the pressure-applying component 20 is at its highest point. After the seatbelt spindle and connector are placed on the support platform 2, the electric telescopic rod 19 drives the pressure-applying component 20 towards the connector. During this process, the pre-pressure rod 23 preferentially contacts the connector, causing the connector to exert pre-pressure on the seatbelt spindle, ensuring stable relative positions between the two. Subsequently, the pressure-applying component 20 continues to move downwards until the pressing part 22 presses against the connector, further increasing the pressure force between the connector and the seatbelt spindle.

[0052] Because the pressing part 22 is positioned closer to the riveting area between the connector and the seat belt spindle, it ensures a uniform and tight fit between the two at the riveting point, significantly improving the heat transfer efficiency of the riveting interface. This facilitates the smooth screwing of the rivet into the seat belt spindle, ensuring riveting quality and connection strength. Furthermore, the two-stage application of pre-pressure and main pressure avoids rigid impact during initial contact while ensuring full fit in the riveting area, achieving an optimized match between the clamping force and the application position.

[0053] As an embodiment of the present invention, a riveting process using the semi-hollow rivet without pre-drilled holes rotary feed riveting device of the aforementioned automotive seat belt mandrel is also proposed, comprising the following steps: Step 1: Place the car seat belt spindle and connector to be riveted on the support platform 2, and start the electric telescopic rod 19 so that the pre-compression structure and the lowering part 22 abut against the connector. Step 2: Control the operation of the drive component according to production needs. First, release the elastic locking structure from locking the switching disk 4. Then, drive the coupling 13 to rotate, so that the corresponding magnetic drive head 5 is switched to the working position. Step 3: Place the rivet of the corresponding specification on the magnetic drive head 5, and then control the magnetic drive head 5 to rotate; Step 4: The lifting frame 3 moves toward the support platform 2 until the rivet abuts against the connector. The friction between the two generates heat, causing the rivet to pass through the connector and partially enter the car seat belt spindle. Step 5: Control the magnetic drive head 5 to stop rotating, and at the same time, the lifting frame 3 further descends, pressing down on the rivet, causing the lower end of the rivet to expand and deform inside the spindle of the car seat belt.

[0054] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0055] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A rotary feed riveting device for semi-hollow rivets without pre-drilled holes on automotive seat belt spindles, comprising: The frame is equipped with a support platform and a switching plate. The switching plate is equipped with multiple sets of magnetic drive heads of different specifications. When the magnetic drive head is switched to the working position, it can rotate actively. Its characteristic is that it further includes: A coupling is coaxially connected to the switching disk. A locking disc is installed on the coupling. The locking disc is provided with multiple sets of locking grooves. An inclined guide surface is connected to the end of the locking groove. A lifting frame is mounted on the machine frame. The lifting frame is equipped with an elastic locking structure. The elastic locking structure cooperates with the locking groove to lock the switching disc axially. A drive assembly is mounted on the frame. The drive assembly can drive the coupling to rotate after the elastic locking structure is separated from the locking disc. When the drive assembly rotates at a predetermined angle, the inclined guide surface can guide the elastic locking structure into the locking groove.

2. The semi-hollow rivet riveting device for automotive seat belt mandrels without pre-drilled holes according to claim 1, characterized in that, The switching disk is provided with an annular groove, which is in rolling cooperation with multiple sets of limit wheels rotatably mounted on the lifting frame.

3. The semi-hollow rivet riveting device for automotive seat belt mandrels without pre-drilled holes according to claim 1, characterized in that, The elastic locking structure includes a bracket mounted on the lifting frame and a horizontal shaft mounted on the bracket. The bracket is provided with a shaft shifting member coaxial with the coupling. The shaft shifting member is slidably connected to the horizontal shaft. A first cylindrical spring is sleeved on the horizontal shaft. The first cylindrical spring is connected to the shaft shifting member. A second convex shaft is provided on the outer side of the shaft shifting component, and the second convex shaft is adapted to the locking groove; The shaft shifting component has a protrusion inside, which abuts and is adapted to the third convex shaft provided on the drive assembly.

4. The semi-hollow rivet riveting device for automotive seat belt mandrels without pre-drilled holes according to claim 3, characterized in that, The protrusion protrudes toward the center of the shaft shifting member and forms a first helical surface, an arc-shaped surface and a second helical surface; The first helical surface engages with the third convex shaft, which can drive the second convex shaft away from the locking groove. The second helical surface engages with the third convex shaft, enabling the second convex shaft to move toward the locking groove.

5. The semi-hollow rivet riveting device for automotive seat belt mandrels without pre-drilled holes according to claim 3, characterized in that, The drive assembly includes a second drive motor mounted on the bracket, and a drive shaft is connected to the output shaft of the second drive motor. The drive shaft is connected to the coupling via a keyway structure. The drive assembly also includes a follower ring coaxially connected to the drive shaft, and the third convex shaft is disposed on the follower ring.

6. The semi-hollow rivet riveting device for automotive seat belt mandrels without pre-drilled holes according to claim 5, characterized in that, The coupling has a hollow interior. The sliding key structure includes a first convex shaft on the drive shaft and an arc-shaped groove on the coupling. The first convex shaft can slide within the arc-shaped groove.

7. The semi-hollow rivet riveting device for automotive seat belt mandrels without pre-drilled holes according to claim 1, characterized in that, Multiple sets of electric telescopic rods are provided on the support platform. A pressure-applying component is connected to the actuating end of the electric telescopic rod. One end of the pressure-applying component is provided with a pressing part, and the other end is provided with a guide shaft. The guide shaft is slidably connected to the support platform. The pressure-applying component is also provided with a pre-pressure structure. When the pressure-applying component moves toward the workpiece, the pre-pressure structure and the pressing part abut against the workpiece in sequence.

8. The semi-hollow rivet riveting device for automotive seat belt mandrels without pre-drilled holes according to claim 7, characterized in that, The pre-compression structure includes a pre-compression rod that slides through the pressure-applying component, and a second cylindrical spring is sleeved on the pre-compression rod. The second cylindrical spring connects the end of the pre-compression rod and the pressure-applying component.

9. A process for riveting using a rotary feed riveting device for semi-hollow rivets without pre-drilled holes for automotive seat belt mandrels as described in any one of claims 1 to 8, characterized in that, Includes the following steps: Step 1: Place the car seat belt spindle and connector to be riveted on the support platform, and start the electric telescopic rod to make the pre-compression structure and the lower pressure part abut against the connector; Step 2: Control the operation of the drive component according to production needs. First, release the elastic locking structure from locking the switching disk, and then drive the coupling to rotate, so that the corresponding magnetic drive head can be switched to the working position. Step 3: Place the rivet of the corresponding specification on the magnetic drive head, and then control the magnetic drive head to rotate; Step 4: The lifting frame moves toward the support platform until the rivet abuts against the connector. The friction between the two generates heat, causing the rivet to pass through the connector and partially enter the spindle of the car seat belt. Step 5: Control the magnetic drive head to stop rotating, and at the same time, the lifting frame further descends, pressing down on the rivet, causing the lower end of the rivet to expand and deform inside the spindle of the car seat belt.

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