Automatic hollow rivet spin riveting machine
By adopting a horizontal symmetrical structure and a double riveting head mechanism controlled by a permanent magnet synchronous motor in the riveting machine, the problems of uneven rivet deformation and unbalanced riveting force are solved, and efficient and stable riveting of hollow rivets is achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SHANGHAI TIEKE BEARING CO LTD
- Filing Date
- 2025-06-05
- Publication Date
- 2026-06-16
AI Technical Summary
Existing riveting machines suffer from problems such as uneven rivet deformation, low efficiency, and poor riveting quality. In particular, hollow rivets cannot be riveted at both ends simultaneously, and the vertical structure leads to an imbalance in riveting force.
The main drive mechanism drives the left-hand riveting head mechanism and the right-hand riveting head mechanism. It adopts a horizontal symmetrical structure and controls the synchronous, same-speed, and reverse movement of the riveting head through a permanent magnet synchronous motor. The symmetrical torque is achieved by combining gear transmission and sliding spline pair. Carbide riveting head and isosceles trapezoidal thread are used to set the riveting torque.
It achieves a stable riveting effect, improves riveting quality and efficiency, ensures consistent riveting at both ends of the rivet, and reduces power consumption during the riveting process.
Smart Images
Figure CN224359318U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to a riveting machine, and in particular discloses an automatic riveting machine for hollow rivets. Background Technology
[0002] Spin riveting is a joining process that uses rotational pressure to deform the rivet. Unlike traditional hammer riveting, spin riveting is generally more precise and has a more uniform pressure distribution. Hollow rivets are hollow, and during spin riveting, the tube wall expands evenly to fit the joined parts, resulting in better connection and less material damage. The uniform pressure applied by the rotating riveting head reduces stress concentration and improves the fatigue resistance of hollow rivets.
[0003] The existing riveting process has the following problems:
[0004] Traditional riveting mechanisms mainly consist of a frame and a lifting module and a rotating module mounted on the frame. The lifting module primarily uses a pneumatic or hydraulic cylinder, while the rotating module mainly includes a riveting head, a lever, and a motor. The pressure rod is mounted on the riveting head, and the motor drives the riveting head to rotate. The riveting head then drives the pressure rod to rotate, and under the drive of the pneumatic / hydraulic cylinder, the pressure rod makes a conical motion around the rivet and presses down on the rivet, thus flattening it and completing the riveting operation. However, because the rotating module moves too quickly during the downward movement driven by the pneumatic / hydraulic cylinder, the impact force of the riveting head on the rivet is too large in a short time, resulting in uneven rivet deformation and poor riveting effect.
[0005] Utility model patent CN222725395U discloses an improved riveting machine, which adopts a lifting module with a lead screw and motor. The lead screw can drive the rotating module to move downwards smoothly and at a uniform speed, avoiding excessive impact force on the rivet by the riveting head in a short time, thus ensuring uniform rivet deformation. However, this structure is still a unidirectional riveting structure, and its structural disadvantages are:
[0006] (1) The rivet is subjected to unidirectional torque during the riveting process, which will cause torsion and deformation, affecting the riveting quality.
[0007] (2) Hollow rivets are hollow cylinders, and both ends need to be riveted. This structure cannot rivet both ends at the same time, resulting in low efficiency.
[0008] When riveting is done separately, the torque applied to the rivet will vary with each riveting process, which can easily cause the riveting cones at both ends of the rivet to be inconsistent in size.
[0009] Existing riveting machines all adopt a vertical structure, and the eccentricity of the structure's own weight can also cause an imbalance in riveting force. Summary of the Invention
[0010] The purpose of this invention is to overcome the defects in the existing technology and provide an automatic riveting machine for hollow rivets that can maintain rivet stability and achieve good riveting effect.
[0011] This utility model is implemented as follows: an automatic riveting machine for hollow rivets, comprising a main drive mechanism, a left-hand riveting head mechanism, and a right-hand riveting head mechanism; the main drive mechanism comprises a permanent magnet synchronous motor, a coupling, a main drive shaft, and a main bevel gear connected in sequence;
[0012] The left-hand riveting head mechanism includes a left gear shaft, the center of which is provided with a first spur gear, and one side end of the left gear shaft meshes with the main bevel gear through a left bevel gear; the first spur gear meshes with a second spur gear, the center of which is connected to the head end of the left-hand riveting shaft, and the tail end of the left-hand riveting shaft passes through the left fixed seat and is connected to the left-hand riveting head; the left-hand riveting shaft is provided with a left trapezoidal thread that meshes with the internal thread of the left fixed seat.
[0013] The right-hand riveting head mechanism includes a right gear shaft, the center of which is provided with a third spur gear. One side of the right gear shaft meshes with the main bevel gear through a right-hand bevel gear. The third spur gear meshes with a fourth spur gear. The center of the fourth spur gear is connected to the head end of the right-hand riveting shaft. The tail end of the right-hand riveting shaft passes through the right fixed seat and is connected to the right-hand riveting head. The right-hand riveting shaft is provided with a right-hand trapezoidal thread that meshes with the internal thread of the right fixed seat.
[0014] The first and third spur gears are small spur gears; the second and fourth spur gears are large spur gears; wherein the number of teeth on the small spur gears is 20 to 30; the number of teeth on the large spur gears is 40 to 60; and the transmission ratio i = 2 to 3.
[0015] The rotational speed of the large spur gear is reduced to 1 / 3 of the rotational speed of the small spur gear, and the torque of the large spur gear is increased to 3 times the torque of the small spur gear.
[0016] The second spur gear is connected to the left-hand riveting shaft, and the fourth spur gear is connected to the right-hand riveting shaft via sliding spline pairs.
[0017] The left and right riveting heads are both cemented carbide riveting heads.
[0018] The left and right trapezoidal threads are both isosceles trapezoidal threads with a tooth angle of 30°.
[0019] The maximum riveting torque of the left and right riveting heads is set by setting the maximum current intensity of the permanent magnet synchronous motor.
[0020] The tail end of the left trapezoidal thread is provided with a first mounting hole (20) for placing the tail end of the left riveting head (10);
[0021] The tail end of the right trapezoidal thread is provided with a second mounting hole (22) for placing the tail end of the right riveting head (17);
[0022] The first mounting hole (20) and the tail end of the left riveting head (10), and the second mounting hole (22) and the tail end of the right riveting head (17) are respectively matched by Morse taper, preferably Morse taper No. 2.
[0023] The beneficial effects of this utility model are as follows: This utility model adopts a horizontal symmetrical structure by setting a left-hand riveting head mechanism and a right-hand riveting head mechanism on both sides of the main drive mechanism, so that the left and right riveting heads move synchronously, at the same speed, and in opposite directions, and apply symmetrical torque to the rivet, thereby making the rivet stable during the riveting process and achieving a good riveting effect. Attached Figure Description
[0024] Figure 1 This is a schematic diagram of the structural transmission system of this utility model.
[0025] Figure 2 This is a schematic diagram showing the connection between the left-hand riveting shaft and the left-hand riveting head of this utility model.
[0026] Figure 3 This is a schematic diagram showing the connection relationship between the right-hand riveting shaft and the right-hand riveting head of this utility model.
[0027] The components are: 1. Permanent magnet synchronous motor; 2. Coupling; 3. Main drive shaft; 4. Main bevel gear; 5. Left gear shaft; 6. First spur gear; 7. Left bevel gear; 8. Second spur gear; 9. Left riveting shaft; 10. Left riveting head; 11. Left trapezoidal thread; 12. Right gear shaft; 13. Third spur gear; 14. Right bevel gear; 15. Fourth spur gear; 16. Right riveting shaft; 17. Right riveting head; 18. Right trapezoidal thread; 19. Left fixed seat; 20. First mounting hole; 21. Right fixed seat; 22. Second mounting hole. Detailed Implementation
[0028] according to Figure 1-3 This utility model is an automatic riveting machine for hollow rivets, including a main drive mechanism, a left-hand riveting head mechanism and a right-hand riveting head mechanism; the main drive mechanism includes a permanent magnet synchronous motor 1, a coupling 2, a main drive shaft 3 and a main bevel gear 4 connected in sequence.
[0029] The left-hand riveting head mechanism includes a left gear shaft 5, with a first spur gear 6 at its center. One end of the left gear shaft 5 meshes with the main bevel gear 4 via a left bevel gear 7. The first spur gear 6 meshes with a second spur gear 8, the center of which is connected to the head end of the left-hand riveting shaft 9. The tail end of the left-hand riveting shaft 9 passes through the left fixed seat 19 and connects to the left-hand riveting head 10. The left-hand riveting shaft 9 has a left trapezoidal thread 11 that meshes with the internal thread of the left fixed seat 19. The right-hand riveting head mechanism has the same structure as the left-hand riveting head mechanism and is symmetrically arranged on the right side of the main drive mechanism.
[0030] The right-hand riveting head mechanism includes a right gear shaft 12, with a third spur gear 13 at its center. One end of the right gear shaft 12 meshes with the main bevel gear 4 via a right bevel gear 14. The third spur gear 13 meshes with a fourth spur gear 15, the center of which is connected to the head end of the right-hand riveting shaft 16. The tail end of the right-hand riveting shaft 16 passes through the right fixed seat 21 and is connected to the right-hand riveting head 17. The right-hand riveting shaft 16 has a right trapezoidal thread 18 that meshes with the internal thread of the right fixed seat 21.
[0031] The first spur gear 6 and the third spur gear 13 are small spur gears; the second spur gear 8 and the fourth spur gear 15 are large spur gears; wherein the number of teeth of the small spur gear is 20~30 teeth; the number of teeth of the large spur gear is 40~60 teeth; and the transmission ratio i = 2~3.
[0032] Preferably, the rotational speed of the large spur gear is reduced to 1 / 3 of the rotational speed of the small spur gear, and the torque of the large spur gear is increased to 3 times the torque of the small spur gear.
[0033] The second spur gear 8 and the left-hand riveting shaft 9, and the fourth spur gear 15 and the right-hand riveting shaft 16, are respectively connected by sliding spline pairs. These sliding spline pairs ensure that the second spur gear 8 and the fourth spur gear 15 can slide freely axially. That is, while transmitting torque, the second spur gear 8 and the fourth spur gear 15 do not affect the axial feed motion of the left-hand riveting shaft 9 and the right-hand riveting shaft 16.
[0034] The left riveting head 10 and the right riveting head 17 are both cemented carbide riveting heads, which greatly improve the wear resistance of the riveting heads.
[0035] according to Figure 2 , Figure 3The left trapezoidal thread 11 and the right trapezoidal thread 18 have thread angles of α=30°, which are isosceles trapezoidal threads. Isosceles trapezoidal threads have high root strength and good centering. The small thread angle reduces the radial component of the axial pressure, and the frictional resistance of the contact area of the left trapezoidal thread 11 and the right trapezoidal thread 18 is reduced, thereby improving transmission efficiency and reducing power consumption.
[0036] The tail end of the left trapezoidal thread 11 is provided with a first mounting hole 20 for placing the tail end of the left riveting head 10; the tail end of the right trapezoidal thread 18 is provided with a second mounting hole 22 for placing the tail end of the right riveting head 17; the first mounting hole 20 and the tail end of the left riveting head 10, and the second mounting hole 22 and the tail end of the right riveting head 17 are respectively matched by Morse taper, preferably Morse taper No. 2.
[0037] The maximum riveting torque of the left riveting head 10 and the right riveting head 17 is set by setting the maximum current intensity of the permanent magnet synchronous motor 1. The forward and reverse rotation of the permanent magnet synchronous motor 1 enables the feed and retraction movements of the left and right riveting heads 10 and 17, thus achieving a fully automatic riveting process. When the motor current reaches the set maximum current intensity value, it indicates that the two parts have been riveted together, and the permanent magnet synchronous motor 1 reverses, automatically disengaging from the riveting process. This achieves full automation of the riveting process.
Claims
1. An automatic riveting machine for hollow rivets, characterized in that: It includes a main drive mechanism, a left-hand riveting head mechanism and a right-hand riveting head mechanism; the main drive mechanism includes a permanent magnet synchronous motor (1), a coupling (2), a main drive shaft (3) and a main bevel gear (4) connected in sequence. The left-hand riveting head mechanism includes a left gear shaft (5), the center of which is provided with a first spur gear (6), and one side of the shaft end of the left gear shaft (5) meshes with the main bevel gear (4) through a left bevel gear (7); the first spur gear (6) meshes with a second spur gear (8), the center of the second spur gear (8) is connected to the head end of the left-hand riveting shaft (9), and the tail end of the left-hand riveting shaft (9) passes through the left fixed seat (19) and is connected to the left-hand riveting head (10); the left-hand riveting shaft (9) is provided with a left trapezoidal thread (11) that meshes with the internal thread of the left fixed seat (19). The right-hand riveting head mechanism includes a right gear shaft (12), the center of which is provided with a third spur gear (13), and one side of the shaft end of the right gear shaft (12) meshes with the main bevel gear (4) through a right bevel gear (14); the third spur gear (13) meshes with a fourth spur gear (15), the center of which is connected to the head end of the right-hand riveting shaft (16), and the tail end of the right-hand riveting shaft (16) passes through the right fixed seat (21) and is connected to the right-hand riveting head (17). The right-hand riveting shaft (16) is provided with a right trapezoidal thread (18) that meshes with the internal thread of the right fixed seat (21).
2. The automatic riveting machine for hollow rivets according to claim 1, characterized in that: The first spur gear (6) and the third spur gear (13) are small spur gears; the second spur gear (8) and the fourth spur gear (15) are large spur gears; wherein the number of teeth of the small spur gear is 20~30 teeth; the number of teeth of the large spur gear is 40~60 teeth; and the transmission ratio i = 2~3.
3. The automatic riveting machine for hollow rivets according to claim 2, characterized in that: The rotational speed of the large spur gear is reduced to 1 / 3 of the rotational speed of the small spur gear, and the torque of the large spur gear is increased to 3 times the torque of the small spur gear.
4. The automatic riveting machine for hollow rivets according to claim 1, characterized in that: The second spur gear (8) is connected to the left-hand riveting shaft (9), and the fourth spur gear (15) is connected to the right-hand riveting shaft (16) via sliding spline pairs.
5. The automatic riveting machine for hollow rivets according to claim 1, characterized in that: The left riveting head (10) and the right riveting head (17) are respectively cemented carbide riveting heads.
6. The automatic riveting machine for hollow rivets according to claim 1, characterized in that: The left trapezoidal thread (11) and the right trapezoidal thread (18) are both isosceles trapezoidal threads with a tooth angle of 30°.
7. The automatic riveting machine for hollow rivets according to claim 1, characterized in that: The maximum riveting torque of the left riveting head (10) and the right riveting head (17) is set by setting the maximum current intensity of the permanent magnet synchronous motor (1).
8. The automatic riveting machine for hollow rivets according to claim 1, characterized in that: The tail end of the left trapezoidal thread (11) is provided with a first mounting hole (20) for placing the tail end of the left riveting head (10); The tail end of the right trapezoidal thread (18) is provided with a second mounting hole (22) for placing the tail end of the right riveting head (17); The first mounting hole (20) and the tail end of the left riveting head (10), and the second mounting hole (22) and the tail end of the right riveting head (17) are respectively matched by Morse taper.