A wheel hub bearing spin riveting assembly clearance control method and spin riveting assembly machine

Abstract

A wheel hub bearing spin riveting assembly clearance control method and a spin riveting assembly machine, wherein the spin riveting assembly machine is provided with a spin riveting turntable assembly and a torque measuring device; during spin riveting assembly of the wheel hub bearing, the wheel hub bearing is fixedly arranged on the spin riveting turntable assembly, the spin riveting head and the spin riveting turntable assembly rotate in the same direction, and the spin riveting head feeds downward to complete the spin riveting assembly of the wheel hub bearing; during the spin riveting assembly process, the torque measuring device accurately detects the spin riveting rotation torque M during the spin riveting assembly process of the wheel hub bearing ， The free rotation torque m after the rivet head is lifted is used to feedback the rivet rotation torque M to control the rivet pressure or position of the rivet head. The free rotation torque m is used to determine whether it falls within the standard rotation torque m. s Within the control range, it is determined whether the negative clearance of the wheel hub bearing is qualified, so as to control the negative clearance of the finished wheel hub bearing during the wheel hub bearing riveting process, thereby greatly reducing the production cost of the wheel hub bearing and improving the product quality and economic benefits of the wheel hub bearing manufacturing company.

Description

Technical Field

[0001] The invention relates to the technical field of wheel hub bearing spin riveting assembly, and in particular to a wheel hub bearing spin riveting assembly clearance control method and a spin riveting assembly machine. Background Art

[0002] The existing wheel hub bearing riveting assembly process control is based on the fixed process parameters obtained after the assembly process experiment to ensure the negative clearance of the wheel hub bearing after riveting assembly; the Chinese invention patent with application number 201710385965.0 discloses a wheel hub bearing unit riveting pressure measurement system and its measurement method, and the Chinese invention patent with application number 202411062431.0 discloses a wheel hub bearing clearance detection system and method, both of which are for detecting the residual axial preload and negative clearance size of the wheel hub bearing after riveting assembly, and can only be applied to the wheel hub bearing assembly process experiment to obtain the corresponding process of the rivet head pressure or position in the riveting assembly. Parameters, but they cannot be applied to the dynamic adjustment control of the rivet head pressure or position process parameters in the wheel hub bearing rivet assembly process; in the actual rivet assembly process of the wheel hub bearing, since its process parameters (rivet head pressure or rivet head position) cannot be adjusted and controlled according to the actual processing shape and position tolerances and material physical parameters (hardness, stiffness, elastic modulus, Poisson's ratio) of each part of the wheel hub bearing, when the rivet process parameters are fixed, the negative clearance of the wheel hub bearing after rivet assembly is completely dependent on the processing accuracy and material physical parameters of each part of the wheel hub bearing. Therefore, the requirements for the processing accuracy and physical parameters of each part of the wheel hub bearing are extremely strict, thereby increasing the production cost of the wheel hub bearing.

[0003] The Chinese invention patent application number 200810158074.2 discloses a hub unit radial CNC riveting device, wherein a torque sensor is provided on one side of the riveting head, the upper end of the torque sensor is connected to a driving servo motor, the lower end is connected to a transmission shaft, the pulley at the lower end of the transmission shaft is connected to the pulley on the connecting plate at the lower end of the riveting head through a belt drive, the riveting head is used for radial riveting of the hub unit, the pulley on the connecting plate at the lower end of the riveting head is used to drive the hub unit's HUB to rotate when the hub unit is radially riveted, and the torque sensor is used to detect the HUB rotation torque during the riveting connection; since the transmission chain of the hub unit's HUB rotation torque during the riveting connection is too long and there are too many influencing factors, the hub unit's HUB torque detection error is too large ; For example, the tightness of the belt used to connect the transmission shaft and the connecting disk at the lower end of the rivet head, the bearing on the transmission shaft and the friction between the bearing of the connecting disk and the pulley will affect the detection accuracy of the HUB torque of the hub unit; when the HUB torque with low detection accuracy is applied to the radial riveting process control of the hub unit, it will inevitably affect the control accuracy of the radial riveting of the hub unit, and ultimately affect the negative clearance accuracy of the hub unit after radial riveting; the invention patent also discloses a riveting clearance control method, which adopts the method of controlling the HUB rotation torque to detect the change of its rotation torque in real time. When the control value is reached, the riveting is stopped immediately, and the riveting quality is judged comprehensively with the monitoring values ​​of pressure, displacement and riveting time, so as to control the negative clearance of the hub bearing after riveting. The technical effect of the present invention is that the rivet clearance control method essentially only provides an idea of ​​dynamically adjusting the rivet head pressure or position process parameters by detecting the rivet torque of the wheel hub bearing during the rivet assembly process of the wheel hub bearing, but it does not provide a specific implementation method; in addition, when the above idea of ​​dynamically adjusting the rivet head pressure or position process parameters by detecting the rivet torque of the wheel hub bearing is applied to the actual rivet assembly process of the wheel hub bearing, due to the influence of the actual processing shape and position tolerances of the various parts of the hub bearing and the physical parameters of the materials (hardness, stiffness, elastic modulus, Poisson's ratio), under the premise of only giving a fixed wheel hub bearing rivet torque parameter and the low measurement accuracy of the wheel hub bearing rivet torque, it is actually impossible to guarantee the negative clearance of the wheel hub bearing after rivet processing. For example, the machining error of the fillet at the upper end of the inner circle of the small inner ring of the hub bearing, or the machining error of the size from the raceway to the bottom of the small inner ring of the hub bearing, or the wall thickness error at the upper end of the small inner ring of the hub bearing, will affect the change in the negative clearance springback amount after the hub bearing is unloaded during the riveting process. Even if the riveting pressure or position is dynamically controlled by a given riveting torque during the riveting process, there is still a large change in the negative clearance springback after unloading the riveting process. In fact, the final negative clearance of the hub bearing product cannot be controlled during the riveting process. Therefore, the radial CNC riveting equipment of the hub unit disclosed in this patent, and the method of controlling the negative clearance of the final product by dynamically adjusting the pressure or position process parameters of the riveting head by detecting the riveting torque of the hub bearing, still need to be further improved.

[0004] Based on the above, how to solve the technical difficulties that the existing wheel hub bearings have strict requirements on the actual processing shape and position tolerances of each part and the physical parameters of the materials, and the wheel hub bearings cannot control the negative clearance of the final product during the riveting assembly process, is of great practical significance to improving the product quality and economic benefits of wheel hub bearing manufacturers. Summary of the invention

[0005] In order to overcome the shortcomings in the background technology, the present invention provides a wheel hub bearing spin riveting assembly clearance control method and a spin riveting assembly machine, which are used to solve the technical problems that the existing wheel hub bearing has strict requirements on the actual processing shape and position tolerances and material physical parameters of each part, the torque detection accuracy is low during the spin riveting process, and the negative clearance cannot be controlled during the spin riveting assembly process.

[0006] In order to solve the above technical problems, the present invention adopts the following technical solutions: a method for controlling clearance of wheel hub bearing spin riveting assembly, a spin riveting assembly machine used for the spin riveting assembly of the wheel hub bearing comprises a fuselage, a spin riveting head, a spin riveting turntable assembly, and a torque measuring device, the spin riveting head is rotatably arranged on the upper side of the fuselage, and the feeding or pressure is controlled by servo; the spin riveting turntable assembly rotates on the lower side of the fuselage; the torque measuring device is fixedly arranged on the side of the spin riveting turntable assembly; when the wheel hub bearing is spin riveted and assembled, it is fixedly arranged on the spin riveting turntable assembly, the spin riveting head and the spin riveting turntable assembly rotate in the same direction, the rotation speed of the spin riveting turntable assembly is less than the rotation speed of the spin riveting head, and the spin riveting head feeds downward at the same time to complete the spin riveting assembly of the wheel hub bearing;

[0007] During the wheel hub bearing riveting assembly process, the torque measuring device detects the riveting rotation torque M during the wheel hub bearing riveting assembly process. ， And the free rotation torque m after the rivet head is lifted; the rivet pressure or position of the rivet head is controlled by feedback of the rivet rotation torque M, and whether the hub bearing rivet assembly is completed is determined by checking whether the free rotation torque m falls within the control range.

[0008] Furthermore, the wheel hub bearing spin riveting assembly process includes more than one spin riveting assembly section, and each spin riveting assembly section is set with a standard spin riveting rotation torque M n , where the standard riveting torque M n The subscript n indicates the number of the rotary riveting assembly section. In each rotary riveting assembly section, the rotary riveting rotation torque M is detected to see whether it reaches the standard rotary riveting rotation torque M of the section. n Feedback controls the pressure or position of the rivet head; when the rivet rotation torque M of the wheel hub bearing reaches the standard rivet rotation torque M of this section n When the riveting pressure is locked, continue to rivet for a certain period of time, then reduce the riveting pressure, rivet flatten for a certain period of time, lift the riveting head to unload the riveting pressure; or when the riveting rotation torque M of the wheel hub bearing reaches the standard riveting rotation torque M of this section nWhen the riveting head is locked, the riveting head is kept in position for a certain period of time, and the riveting head is lifted to unload the riveting pressure.

[0009] If the free rotation torque m detected in a certain riveting assembly section is less than the standard rotation torque m s When the control range reaches the lower limit, continue to the next riveting assembly section until the free rotation torque m is detected to fall within the standard rotation torque m. s When the wheel hub bearing is within the control range, the riveting assembly is completed; or the riveting rotation torque M n Exceeding the maximum setting value M M At this time, the wheel hub bearing riveting assembly is completed.

[0010] Furthermore, the rotary riveting torque of the first rotary riveting assembly section is M1, and the standard rotary riveting torque corresponding to each subsequent rotary riveting assembly section is M1. n Increase successively until the maximum setting value M M .

[0011] Furthermore, the standard rotation torque of the hub bearing is m s The method is as follows: select several hub bearings that have completed the spin riveting assembly and are within the negative clearance range required by the standard, divide them into several groups, and measure their free rotation torque m at the set speed (the set speed is equal to the rotation speed of the spin riveting turntable assembly during the spin riveting assembly of the hub bearing), and make a mean standard deviation control chart of the free rotation torque m , with the mean standard deviation control chart of the rotation torque m The upper control line UCL and the lower control line LCL are used as the standard rotation torque m s Control scope.

[0012] Furthermore, the riveting rotation torque M1 of the first riveting assembly section of the hub bearing is measured by experiment, and the method is as follows:

[0013] S5.1. Based on the original wheel hub bearing riveting assembly process parameters (the riveting head speed in the original wheel hub bearing riveting assembly process parameters is equal to the speed difference between the riveting head and the riveting turntable assembly), several wheel hub bearings are divided into several groups and riveted on the riveting assembly machine for riveting assembly experiments. During the riveting assembly experiment, the riveting rotation torque of the wheel hub bearing is detected and recorded. , and detect and record free rotation torque ; Calculate the average torque of several groups of rivet rotation ; Make free rotation torque Mean standard deviation control chart for ;

[0014] S5.2, free rotation torque Mean standard deviation control chart for Control chart of mean standard deviation of free rotation torque m For comparison, if the free-wheeling torque Mean standard deviation control chart for Upper control line , greater than the mean standard deviation control chart of the free rotation torque m If the upper control line UCL is found, modify the rivet head pressure or position in the original wheel hub bearing rivet assembly process parameters and conduct the wheel hub bearing rivet assembly experiment again;

[0015] S5.3, repeat the above steps until the free rotation torque Mean standard deviation control chart for Upper control line Mean standard deviation control chart equal to or slightly less than free rotation torque m The upper control line UCL, at this time the average value of the rivet rotation torque The riveting rotation torque M1 is the first riveting assembly stage of the wheel hub bearing.

[0016] Furthermore, the maximum riveting torque of the hub bearing M M The method is measured by experiment:

[0017] S6.1. Based on the original wheel hub bearing riveting assembly process parameters (the rotation speed of the riveting head in the original wheel hub bearing riveting assembly process parameters is equal to the rotation speed difference between the riveting head and the riveting turntable assembly), several wheel hub bearings are divided into several groups and riveted on the riveting assembly machine for riveting assembly experiments. During the riveting assembly experiment, the rotation torque of the wheel hub bearing riveting is detected and recorded. , and detect and record free rotation torque ; Calculate the average torque of several groups of rivet rotation ; Make free rotation torque Mean standard deviation control chart for ;

[0018] S6.2, free rotation torque Mean standard deviation control chart for Control chart of mean standard deviation of free rotation torque m For comparison, if the free-wheeling torque Mean standard deviation control chart for Lower control line , less than the mean standard deviation control chart of free rotation torque m If the lower control line LCL is reached, modify the rivet head pressure or position in the original wheel hub bearing rivet assembly process parameters, and conduct the wheel hub bearing rivet assembly experiment again;

[0019] S6.3, repeat the above steps until the free rotation torque Mean standard deviation control chart for Lower control line Mean standard deviation control chart equal to or slightly greater than free rotation torque m The lower control line LCL, at this time the average value of the rivet rotation torque As the maximum riveting torque of the wheel hub bearing M M .

[0020] Furthermore, the standard rivet rotation torque M is set for each subsequent rivet assembly stage. n+1 , compared with the standard rivet rotation torque M set in the previous rivet assembly section n , increasing in increments of 5-20% of the riveting torque range.

[0021] A rotary riveting assembly machine, wherein a torque measuring device comprises a force measuring rod fixedly arranged on the rear side of a machine body, and four resistance strain gauges fixedly pasted on vertical surfaces on both sides of the force measuring rod.

[0022] Preferably, the torque measuring device includes a force measuring rod rotatably arranged on the rear side of the fuselage, and a force measuring sensor fixedly arranged on the rear side of the fuselage, and the force measuring rod is fixedly provided with a force measuring head on the side surface close to the end of the fuselage; when the torque measuring device detects the rotary riveting torque of the wheel hub bearing, the force measuring head contacts the force measuring sensor.

[0023] Furthermore, the rotary riveting turntable assembly includes a turntable, a positioning column, and a pressure block. The positioning column is fixedly arranged on the upper surface of the turntable, and the pressure block is movably arranged on the upper surface of the turntable. A bearing box assembly is fixedly arranged at the lower part of the rotary riveting turntable assembly. The rotary riveting turntable assembly is driven by the main shaft in the bearing box assembly to rotate. The main shaft is directly driven to rotate by the turntable motor, or the turntable motor and the main shaft are driven and connected by a synchronous belt; or the turntable motor and the main shaft are driven and connected by gear meshing.

[0024] Due to the adoption of the technical scheme as described above, the present invention has the following beneficial effects: the present invention discloses a wheel hub bearing rotary riveting assembly clearance control method and a rotary riveting assembly machine, and the hub bearing rotary riveting assembly machine is provided with a rotary riveting turntable assembly and a torque measuring device; when the wheel hub bearing is rotary riveted, the wheel hub bearing is fixedly arranged on the rotary riveting turntable assembly, the rotary riveting head and the rotary riveting turntable assembly rotate in the same direction, and the rotary riveting head feeds downward to complete the rotary riveting assembly of the wheel hub bearing; during the rotary riveting assembly process, the torque measuring device does not need to pass through a transmission chain or the transmission chain is short, so the detection of the rotary riveting rotation torque M during the rotary riveting assembly process of the wheel hub bearing and the free rotation torque m after the rotary riveting head is lifted has extremely high accuracy; in the rotary riveting assembly clearance control method of the present invention, the rotary riveting assembly includes more than one rotary riveting assembly section, and each rotary riveting assembly section controls the rotary riveting pressure or position of the rotary riveting head through the feedback of the rotary riveting rotation torque M, and checks whether the free rotation torque m falls within the standard rotation torque m sWithin the control range, it is used to determine whether the hub bearing rotary riveting assembly is completed, and the dynamic adjustment of the rotary riveting rotation torque M is realized. Through the dynamic adjustment of the rotary riveting rotation torque M, it is adapted to the influence of the actual processing shape and position tolerances of each part of the hub bearing and the physical parameters of the material on the rotary riveting parameters, so as to achieve the technical effect of negative clearance control in the hub bearing assembly process; the hub bearing rotary riveting assembly clearance control method and rotary riveting assembly machine of the invention overcome the problem that the rotary riveting rotation torque M, the rotary riveting head pressure or the rotary riveting head position process parameters cannot be dynamically adjusted based on the actual processing shape and position tolerances of the parts and the physical parameters of the material in the existing hub bearing rotary riveting assembly process, which greatly reduces the stringent requirements on the actual processing shape and position tolerances and material physical parameters of each part of the hub bearing, and at the same time ensures the control of negative clearance in the hub bearing assembly process, thereby greatly reducing the production cost of the hub bearing and improving the product quality and economic benefits of the hub bearing manufacturing enterprise. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a schematic diagram of the appearance of the wheel hub bearing spin riveting assembly clearance control method according to the first embodiment;

[0026] Figure 2 This is a schematic diagram of the appearance of the wheel hub bearing;

[0027] Figure 3 It is a schematic diagram of the cross-sectional structure of a wheel hub bearing;

[0028] Figure 4 It is a schematic diagram of the working state of the wheel hub bearing spin riveting assembly clearance control method of the first embodiment;

[0029] Figure 5 It is a top view schematic diagram of the clearance control method of the hub bearing spin riveting assembly according to the first embodiment;

[0030] Figure 6 It is a schematic diagram of the appearance of the rotary riveting turntable assembly and the bearing box assembly;

[0031] Figure 7 It is a cross-sectional structural schematic diagram of a wheel hub bearing spin riveting assembly clearance control method according to Embodiment 1;

[0032] Figure 8 This is a schematic diagram of the appearance of a wheel hub bearing spin riveting assembly clearance control method according to Embodiment 2;

[0033] Fig. 9 It is a top view schematic diagram of the clearance control method for the spin riveting assembly of a hub bearing according to the second embodiment.

[0034] In the figure: 1. Riveting head; 2. Riveting turntable assembly; 2.1. Turntable; 2.2. Positioning column; 2.3. Pressure block; 3. Force measuring rod; 3.1. Resistance strain gauge; 3.2. Force measuring head; 4. Hub bearing; 4.1. Flange inner ring; 4.1.1. Flange inner ring rivet joint; 4.2. Flange outer ring; 4.2.1. Flange connecting ear; 4.3. Small inner ring; 4.4. Rolling element; 5. Bearing box assembly; 5.1. Bearing box; 5.2. Spindle; 5.3. Tapered bearing; 5.4. Large synchronous wheel; 5.5. Bearing spacer; 5.6. Bearing back nut; 5.7. Bearing end cover; 6. Turntable motor; 6.1. Small synchronous wheel; 7. Synchronous belt; 8. Force sensor. DETAILED DESCRIPTION

[0035] The present invention can be explained in detail by the following examples, and the purpose of disclosing the present invention is to protect all technical improvements within the scope of the present invention.

[0036] The structure of wheel hub bearing 4 is shown in the attached manual. Figure 2 , 3 : It includes a flange inner ring 4.1, a flange outer ring 4.2, a small inner ring 4.3, and a rolling body 4.4, wherein the upper end of the flange inner ring 4.1 is provided with a flange inner ring rivet joint 4.1.1, wherein the outer side of the flange outer ring 4.2 is provided with a flange connection ear 4.2.1.

[0037] A rotary riveting assembly machine is used for the rotary riveting assembly of the above-mentioned wheel hub bearing 4; see the attached manual Figure 1: The wheel hub bearing spin riveting assembly clearance control method includes a fuselage, a spin riveting head 1 rotatably arranged on the upper side of the fuselage, a spin riveting turntable assembly 2 rotatably arranged on the lower side of the fuselage, and a torque measuring device is fixedly arranged on the side of the spin riveting turntable assembly 2, wherein the feed or pressure of the spin riveting head 1 is servo controlled; the fuselage adopts a C-type fuselage, an integrated casting molding process, and is subjected to aging stress relief treatment, and has the advantages of high fuselage rigidity and stability. A gantry fuselage can also be adopted, which is welded from steel plates and has the advantages of short production cycle and low cost; when the wheel hub bearing 4 is spin riveted and assembled, the wheel hub bearing 4 is fixedly arranged On the riveting turntable assembly 2, the riveting head 1 and the riveting turntable assembly 2 rotate in the same direction, and the rotation speed of the riveting turntable assembly 2 is lower than that of the riveting head 1 to form a speed difference. At the same time, the riveting head 1 feeds downward to complete the riveting assembly of the hub bearing 4. When the hub bearing 4 is riveted, the flange inner ring 4.1 rotates with the riveting turntable assembly 2, and the flange connection ear 4.2.1 of the flange outer ring 4.2 is blocked by the torque measuring device and remains motionless, so that the flange inner ring 4.1 and the flange outer ring 4.2 will produce relative rotation. During the riveting assembly process, the rolling body 4.4 is relative to the flange inner ring 4. 1. The raceway positions of the flange outer ring 4.2 and the small inner ring 4.3 are continuously changed, which can prevent the rolling element 4.4, the flange inner ring 4.1, the flange outer ring 4.2, and the small inner ring 4.3 from being repeatedly affected by impact loads at fixed positions during the riveting assembly process, thereby improving the impact of the riveting assembly on the service life of the hub bearing; during the riveting assembly of the hub bearing 4, as the riveting head feeds downward, the pressure gradually increases, causing the flange inner ring rivet joint 4.1.1 to undergo plastic deformation and flip outward, and press on the upper end surface of the small inner ring 4.3, causing the hub bearing 4 to have a large negative clearance At this time, the relative rotation between the flange inner ring 4.1 and the flange outer ring 4.2 will produce a riveting rotation torque, which is transmitted to the torque measuring device through the flange connection ear 4.2.1 of the flange outer ring 4.2, so that the riveting rotation torque between the flange inner ring 4.1 and the flange outer ring 4.2 can be measured (in actual operation, the torque measuring device measures the thrust generated by the flange connection ear 4.2.1 on the torque measuring device, and the riveting rotation torque between the flange inner ring 4.1 and the flange outer ring 4.2 can be obtained by calculation); and the flange inner ring 4.1 and the flange outer ring 4.2 is positively correlated with the process parameters of the maximum pressure of the rivet head (pressure control mode) or the final position of the rivet head (position control mode), and the maximum pressure of the rivet head or the final position of the rivet head is positively correlated with the free rotation torque corresponding to the negative clearance after the hub bearing 4 is riveted. Therefore, the rivet rotation torque in the hub bearing riveting assembly process can be used to feedback control the rivet head pressure or rivet head position, and finally achieve the purpose of controlling the negative clearance after the hub bearing is assembled (actually the free rotation torque within the standard range of the negative clearance requirement after the hub bearing is assembled); the corresponding relationship between the rivet rotation torque range in the hub bearing riveting assembly process and the free rotation torque within the standard range of the negative clearance requirement after the hub bearing is assembled can be obtained through assembly process experiments. .

[0038] For further information, see the attached manual. Figure 1 , 5 The torque measuring device includes a force measuring rod 3 fixedly arranged on the rear side of the C-shaped fuselage, and four resistance strain gauges 3.1 fixedly pasted on the vertical surfaces on both sides of the force measuring rod 3. The four resistance strain gauges 3.1 constitute a measuring bridge for detecting the thrust of the flange connection ear 4.2.1 on the outer end of the force measuring rod 3. The rotational torque of the hub bearing 4 can be obtained by calculating the thrust. This torque measuring device can directly measure the thrust on the outer end of the force measuring rod 3 and has the advantage of high precision, but the torque measuring device needs to be homemade.

[0039] Preferably, see the attached specification Figure 8 , 9 The torque measuring device includes a force measuring rod 3 rotatably arranged on the rear side of the C-shaped fuselage, and a force measuring sensor 8 fixedly arranged on the rear side of the C-shaped fuselage. The force measuring rod 3 is fixedly provided with a force measuring head 3.2 on the side near the end of the C-shaped fuselage. When the outer end of the force measuring rod 3 is subjected to the thrust of the flange connecting ear 4.2.1, the force measuring head 3.2 contacts the force measuring sensor 8, and the thrust of the flange connecting ear 4.2.1 on the outer end of the force measuring rod 3 is detected by the force measuring sensor 8. This torque measuring device adopts a commercially available finished force measuring sensor 8, which has the advantages of easy procurement and no need for self-production.

[0040] For further information, see the attached manual. Figure 6:The rotary riveting turntable assembly 2 includes a turntable 2.1, a positioning column 2.2, and a pressure block 2.3. The positioning column 2.2 is fixedly arranged on the upper disk surface of the turntable 2.1, and the pressure block 2.3 is movably arranged on the upper disk surface of the turntable 2.1 through a locking bolt; when the wheel hub bearing 4 is subjected to rotary riveting processing, the bolt hole on the flange inner ring 4.1 cooperates with the positioning column 2.2 to realize the positioning of the flange inner ring 4.1 on the rotary riveting turntable assembly 2, and the locking bolt is used to enable the pressure block 2.3 to realize fixed connection between the flange inner ring 4.1 and the turntable 2.1; in addition, for the wheel hub bearing 4 with connecting bolts pre-installed on the flange inner ring 4.1, the turntable 2.1 is no longer equipped with the positioning column 2.2, but a positioning hole is reserved, and the connecting bolts pre-installed on the flange inner ring 4.1 cooperate with the positioning hole to realize the positioning of the flange inner ring 4.1 on the rotary riveting turntable assembly 2.

[0041] For further information, see the attached manual. Figure 6 , 7 : The lower part of the rotary riveting turntable assembly 2 is fixedly provided with a bearing box assembly 5; the rotary riveting turntable assembly 2 is driven by the main shaft 5.2 in the bearing box assembly 5 to rotate; the main shaft 5.2 is driven to rotate by the turntable motor 6.

[0042] For further information, see the attached manual. Figure 7 : Both the turntable motor 6 and the main shaft 5.2 are provided with synchronous gear wheels, and the turntable motor 6 and the main shaft 5.2 are driven and connected by a synchronous belt 7; or both the turntable motor 6 and the main shaft 5.2 are provided with gears, and the turntable motor 6 and the main shaft 5.2 are driven and connected by gear meshing. Embodiment 1:

[0043] A rotary riveting assembly machine, see the attached manual Figure 7 : It includes a C-shaped fuselage, a rivet head 1 rotatably arranged on the upper side of the C-shaped fuselage, a rivet turntable assembly 2 rotatably arranged on the lower side of the C-shaped fuselage, a bearing box assembly 5 and a turntable motor 6 fixedly arranged in the cavity on the lower side of the C-shaped fuselage, a force measuring rod 3 fixedly arranged on the rear side of the C-shaped fuselage, and a control system; wherein the feed and pressure of the rivet head 1 are controlled by hydraulic servo;

[0044] See the instruction manual Figure 6 : The rotary riveting turntable assembly 2 includes a turntable 2.1, a positioning column 2.2, and a pressure block 2.3. The positioning column 2.2 is fixedly arranged on the upper surface of the turntable 2.1, and the pressure block 2.3 is movably arranged on the upper surface of the turntable 2.1 through a locking bolt;

[0045] See the instruction manual Figure 7: The bearing box assembly 5 includes a bearing box body 5.1, a main shaft 5.2, a tapered bearing 5.3, a large synchronous wheel 5.4, a bearing spacer 5.5, a bearing back-tightening nut 5.6, and a bearing end cover 5.7; two sets of tapered bearings 5.3 are arranged back to back, separated by a bearing spacer 5.5, and arranged in the inner cavity of the bearing box body 5.1, and the bearing end cover 5.7 is fixedly arranged at the upper end of the bearing box body 5.1 to press the outer sleeve of the upper tapered bearing 5.3; the main shaft 5.2 is arranged in the inner sleeves of the two sets of tapered bearings 5.3, and is connected with the inner sleeves of the tapered bearings 5.3 by interference fit, the inner sleeve of the upper tapered bearing 5.3 is in contact with the shoulder of the main shaft 5.2, and the inner sleeve of the lower tapered bearing 5.3 is in contact with the bearing back-tightening nut 5.6, and the bearing back-tightening nut 5.6 is connected to the main shaft 5.2 through a thread; The step wheel 5.4 is arranged at the lower end of the main shaft 5.2 and is fixedly connected to the main shaft 5.2 by a saddle screw; the bearing box assembly 5 is arranged in the lower side cavity of the C-type fuselage and is fixedly connected to the top plate of the lower side cavity of the C-type fuselage by bolts; the turntable 2.1 is fixed to the upper end of the main shaft 5.2 by bolts; the turntable motor 6 is fixedly arranged on the longitudinal partition of the lower side cavity of the C-type fuselage through a motor bracket, and a small synchronous wheel 6.1 is connected to the output shaft of the turntable motor 6 by a flat key; the small synchronous wheel 6.1 and the large synchronous wheel 5.4 are connected by a synchronous belt 7; in this embodiment, a large gear can also be fixedly arranged on the lower end of the main shaft 5.2, and a small gear can also be fixedly arranged on the output shaft of the turntable motor 6, and the main shaft 5.2 and the output shaft of the turntable motor 6 are connected by a large and small gear meshing transmission; see the attached manual Figure 5 The force measuring rod 3 is fixedly arranged at the rear side of the C-shaped fuselage by bolts, and four resistance strain gauges 3.1 are symmetrically pasted and fixedly arranged on the vertical surfaces on both sides of the force measuring rod 3, and the four resistance strain gauges 3.1 constitute a measuring bridge.

[0046] Before the wheel hub bearing 4 is riveted, the bolt holes on the flange inner ring 4.1 cooperate with the positioning columns 2.2 to realize the positioning of the flange inner ring 4.1 on the turntable 2.1, and the pressing block 2.3 is fixedly connected to the flange inner ring 4.1 and the turntable 2.1 by the locking bolts; when the wheel hub bearing 4 is riveted, the riveting head 1 and the riveting turntable assembly 2 rotate clockwise in the same direction, and the rotation speed of the riveting turntable assembly 2 is less than the rotation speed of the riveting head 1 to form a speed difference, and the riveting head 1 feeds downward to complete the riveting assembly of the wheel hub bearing 4; during the riveting assembly of the wheel hub bearing 4, the flange inner ring 4.1 rotates with the riveting turntable assembly 2, and the flange connection ear 4.2.1 of the flange outer ring 4.2 is blocked by the force measuring rod 3 and remains motionless, and the flange inner ring 4 .1 and the flange outer ring 4.2 will produce relative rotation. As the pressure of the rivet head increases, the flange inner ring rivet head 4.1.1 undergoes plastic deformation of flipping outward and presses on the upper end surface of the small inner ring 4.3, causing a large negative clearance in the hub bearing 4. At this time, the relative rotation between the flange inner ring 4.1 and the flange outer ring 4.2 will produce a rivet rotation torque, and the magnitude of the rivet rotation torque is positively correlated with the magnitude of the negative clearance of the hub bearing 4. The rivet rotation torque is transmitted to the force measuring rod 3 through the flange connecting ear 4.2.1 of the flange outer ring 4.2, causing it to undergo elastic deformation, and then the rivet rotation torque between the flange inner ring 4.1 and the flange outer ring 4.2 is measured by the measuring bridge composed of four resistance strain gauges 3.1.

[0047] A method for controlling clearance of a hub bearing during spin riveting assembly is provided. Based on the spin riveting assembly machine of the above structure, the spin riveting rotating torque M is used to feedback and control the spin riveting pressure working mode of the spin riveting head. When the hub bearing 4 is spin riveted, the hub bearing 4 is fixedly arranged on the spin riveting turntable assembly 2, the spin riveting head 1 and the spin riveting turntable assembly 2 rotate in the same direction, the rotation speed of the spin riveting turntable assembly 2 is less than the rotation speed of the spin riveting head 1, and the spin riveting head 1 is fed downward to complete the spin riveting assembly of the hub bearing 4.

[0048] During the spin riveting assembly process of the wheel hub bearing 4, the torque measuring device detects the spin riveting rotation torque M during the spin riveting assembly process of the wheel hub bearing 4. ， and the free rotation torque m after the rivet head 1 is lifted; the rivet pressure of the rivet head 1 is controlled by feedback of the rivet rotation torque M, and whether the rivet assembly of the hub bearing 4 is completed is judged by the free rotation torque m;

[0049] The spin riveting assembly process of the wheel hub bearing 4 includes more than one spin riveting assembly section. The number of spin riveting assembly sections is not fixed and is determined by automatic control according to the actual assembly process. Each spin riveting assembly section is set with a standard spin riveting rotation torque M. n , the standard riveting torque M set for each subsequent riveting assembly stage n+1 , compared with the standard rivet rotation torque M set in the previous rivet assembly section n , in order of riveting torque range (M M-M1) by 5-20%; the standard riveting torque M n The subscript n indicates the number of the rotary riveting assembly section. In each rotary riveting assembly section, the rotary riveting rotation torque M is detected to see whether it reaches the standard rotary riveting rotation torque M of the section. n Feedback control of the riveting head pressure; when the riveting rotation torque M of the hub bearing 4 reaches the standard riveting rotation torque M of this section n When the riveting pressure is locked, continue to rivet for a certain period of time, then reduce the riveting pressure, rivet flattening for a certain period of time, and lift the riveting head to unload the riveting pressure;

[0050] If the free rotation torque m detected in a certain riveting assembly section is less than the standard rotation torque m s When the control range reaches the lower limit, continue to the next riveting assembly section until the free rotation torque m is detected to fall within the standard rotation torque m. s When the riveting torque M is within the control range, the hub bearing 4 is assembled and riveted; or n Exceeding the maximum setting value M M At this time, the wheel hub bearing 4 is riveted and assembled, but the wheel hub bearing 4 is a defective product and needs to be removed for defective cause analysis;

[0051] For the same type of wheel hub bearing, the first riveting assembly section riveting torque M1, the maximum riveting torque M M is a fixed value, standard rotation torque m s is a fixed control range (rotation torque mean standard deviation control chart The upper control line UCL and the lower control line LCL); the riveting rotation torque M of the middle riveting section n In order of riveting torque range (M M -M1) by 5-20% increments, up to M M ; The first riveting assembly section riveting rotation torque M1, the maximum riveting rotation torque M M , Standard rotation torque m s The control ranges were obtained through experiments;

[0052] Wheel hub bearing standard rotation torque m s The actual measurement method is: select 36 wheel hub bearings 4 that have completed the spin riveting assembly and are within the negative clearance range required by the standard as test samples, divide them into 6 groups, measure the free rotation torque m of the 6 groups of samples at the set speed (the set speed is equal to the speed of the spin riveting turntable assembly 2 during the spin riveting assembly of the wheel hub bearing, which is 180r / min), and make a mean standard deviation control chart of the free rotation torque m , with the mean standard deviation control chart of the rotation torque m The upper control line UCL and the lower control line LCL are used as the standard rotation torque m s Scope of control;

[0053] The experimental method for the riveting rotation torque M1 of the first riveting assembly section of the wheel hub bearing is:

[0054] S5.1. Then, 36 wheel hub bearings 4 to be assembled by riveting are selected and divided into 6 groups. The wheel hub bearing 4 riveting assembly experiment is carried out with the original wheel hub bearing 4 riveting assembly process parameters (including the riveting head rotation speed, the riveting head feed speed, the riveting head pressure, and the leveling time. The riveting speed in the original wheel hub bearing 4 riveting assembly process parameters is equal to the speed difference between the riveting head 1 and the riveting turntable assembly 2, which is 360r / min). During the riveting assembly experiment, the riveting machine control system automatically detects and records the riveting rotation torque of each wheel hub bearing 4. , and detect and record free rotation torque , and calculate the average torque of the six groups of rivet rotation , making free rotation torque Mean standard deviation control chart for ;

[0055] S5.2, free rotation torque Mean standard deviation control chart for Control chart of mean standard deviation of free rotation torque m For comparison, if the free-wheeling torque Mean standard deviation control chart for Upper control line , greater than the mean standard deviation control chart of the free rotation torque m If the upper control line UCL is obtained, the rivet head pressure in the original wheel hub bearing rivet assembly process parameters is reduced by 3% (three times the rivet head pressure control accuracy), and 36 wheel hub bearings 4 to be rivet assembled are randomly selected, and the wheel hub bearing rivet assembly experiment is performed again according to the above step S5.1;

[0056] S5.3, repeat steps S5.1 and S5.2 until the free rotation torque Mean standard deviation control chart for Upper control line Mean standard deviation control chart equal to or slightly less than free rotation torque m The upper control line UCL, at this time, the average torque of the six groups of rivets The riveting rotation torque M1 as the first riveting assembly section of the wheel hub bearing;

[0057] Wheel hub bearing 4 maximum riveting torque M M The experimental method is:

[0058] S6.1. Then, 36 wheel hub bearings 4 to be assembled by riveting are selected and divided into 6 groups. The wheel hub bearing 4 riveting assembly experiment is carried out with the original wheel hub bearing 4 riveting assembly process parameters (including the riveting head rotation speed, the riveting head feed speed, the riveting head pressure, and the leveling time. The riveting speed in the original wheel hub bearing 4 riveting assembly process parameters is equal to the speed difference between the riveting head 1 and the riveting turntable assembly 2, which is 360r / min). During the riveting assembly experiment, the riveting machine control system automatically detects and records the riveting rotation torque of each wheel hub bearing 4. , and detect and record free rotation torque , and calculate the average torque of the six groups of rivet rotation , making free rotation torque Mean standard deviation control chart for ;

[0059] S6.2, free rotation torque Mean standard deviation control chart for Control chart of mean standard deviation of free rotation torque m For comparison, if the free-wheeling torque Mean standard deviation control chart for Lower control line , less than the mean standard deviation control chart of free rotation torque m If the lower control line LCL is obtained, the rivet head pressure in the original wheel hub bearing rivet assembly process parameters is increased by 3% (three times the rivet head pressure control accuracy), and 36 wheel hub bearings 4 to be rivet assembled are randomly selected, and the wheel hub bearing rivet assembly experiment is performed again according to the above step S5.1;

[0060] S6.3, repeat the steps of S5.1 and S5.2 until the free rotation torque Mean standard deviation control chart for Lower control line Mean standard deviation control chart equal to or slightly greater than free rotation torque m The lower control line LCL, at this time, the average torque of the six groups of rivets As the maximum riveting torque of the wheel hub bearing M M .

[0061] The following specifically describes the spin riveting assembly process of the wheel hub bearing using the pressure control mode. This control mode is applied to the spin riveting assembly machine using the hydraulic servo control spin riveting head 1 feed and pressure control; the spin riveting rotation torque M1 of the first spin riveting assembly section is 3.9Nm, and the maximum spin riveting rotation torque M M is 4.5Nm; control chart of mean standard deviation of free rotation torque m The upper control line UCL is 1.2Nm, the lower control line LCL is 1.12Nm, and the center value is 1.16Nm;

[0062] When the hub bearing 4 is riveted, the hub bearing is fixedly arranged on the riveting turntable assembly 2, and the flange connection ear 4.2.1 contacts the outer end of the force measuring rod 3; the riveting head 1 rotates clockwise at a speed of 540r / min, and the feed speed is 1.0mm / s; the turntable 2.1 drives the flange inner ring 4.1 to rotate clockwise at a speed of 180r / min, and the flange outer ring 4.2 remains stationary; the speed difference between the riveting head 1 and the flange inner ring 4.1 is 360r / min (the speed difference is the speed of the riveting head of the original hub bearing 4 riveting assembly, and the other riveting process parameters are the same as the original hub bearing 4 riveting assembly process parameters), that is, the actual riveting speed of the riveting head 1 is 360r / min;

[0063] As the rivet head 1 is fed into the first rivet assembly section, the rivet head 1 contacts the flange inner ring rivet head 4.1.1, and the rivet head 1 continuously presses the flange inner ring rivet head 4.1.1 at the set feed speed and rivet rotation speed, causing it to undergo plastic deformation of flipping outward and pressing on the upper end face of the small inner ring 4.3; in this process, as the pressure of the rivet head 1 gradually increases, the plastic deformation of the flange inner ring rivet head 4.1.1 also increases synchronously, and at the same time, the pressure on the upper end face of the small inner ring 4.3 also gradually increases, resulting in an increase in the negative clearance of the wheel hub bearing 4, and a gradual increase in the rivet rotation torque between the flange inner ring 4.1 and the flange outer ring 4.2; the measuring bridge on the force measuring rod 3 continuously measures the internal and external forces between the flange inner ring 4.1 and the flange outer ring When the measured rivet rotation torque reaches the rivet rotation torque M1 of the first rivet assembly section of 3.9Nm, feedback control is used to lock the pressure of the rivet head 1, and the rivet head 1 continues to work for 0.67s under the locking pressure (i.e., the rivet head 1 spins 4 circles) to complete the plastic deformation of the rivet joint 4.1.1 of the inner ring of the spun flange; then the pressure of the rivet head 1 is reduced to 70%-80% of the locking pressure, and the rivet is continued for 0.67s to level, and the rivet head is lifted by 1.0mm; after the rivet head 1 is lifted and depressurized, if the free rotation torque m of the hub bearing 4 falls between the upper control line UCL of 1.2Nm and the lower control line LCL of 1.12Nm, the hub bearing 4 rivet assembly is completed;

[0064] After the rivet head 1 is lifted and pressure-relieved in the first riveting assembly section, if the free rotation torque m of the hub bearing 4 is less than 1.12Nm of the lower control line LCL, the second riveting assembly section is carried out; in the second riveting assembly section, the riveting rotation torque M2 of the hub bearing 4 increases to 4.02Nm by 20% of the riveting rotation torque range (4.5-3.9=0.6Nm), that is, in the second riveting assembly section, when the measured riveting rotation torque M2 reaches 4.02Nm, the feedback control locks the riveting head 1 pressure riveting for 0.67s, and then the pressure of the riveting head 1 is reduced to 70%-80% of the locking pressure, and then the riveting is continued for 0.67s, and the riveting is lifted by 1.0mm; after the rivet head 1 is lifted and pressure-relieved, if the free rotation torque m of the hub bearing 4 falls between 1.2Nm of the upper control line UCL and 1.12Nm of the lower control line LCL, the riveting assembly of the hub bearing 4 is completed;

[0065] After the rivet head 1 is lifted and pressure-relieved in the second rivet assembly section, if the free rotation torque m of the hub bearing 4 is still less than 1.12Nm of the lower control line LCL, the third rivet assembly section is carried out; in the third rivet assembly section, the rivet rotation torque M2 of the hub bearing 4 increases to 4.14Nm by 20% of the rivet rotation torque range (4.5-3.9=0.6Nm), that is, in the third rivet assembly section, when the measured rivet rotation torque M2 reaches 4.14Nm, feedback control is used to lock the rivet head 1 pressure rivet for 0.67s, and then the pressure of the rivet head 1 is reduced to 70%-80% of the locking pressure, and then the rivet is continuously leveled for 0.67s, and the rivet head is lifted by 1.0mm; after the rivet head 1 is lifted and pressure-relieved, if the free rotation torque m of the hub bearing 4 falls between 1.2Nm of the upper control line UCL and 1.12Nm of the lower control line LCL, the rivet assembly of the hub bearing 4 is completed;

[0066] By analogy, after the fifth riveting assembly section is completed, if the free rotation torque m of the hub bearing 4 is still less than 1.12Nm of the lower control line LCL, the riveting assembly of the hub bearing 4 is also completed; but the hub bearing 4 is judged as a defective product at this time, and the cause of the defect needs to be analyzed. Embodiment 2:

[0067] The rotary riveting assembly machine of the second embodiment is different from the first embodiment in that the rotary riveting head 1 is fed by a servo motor and the torque measuring device is structured; see the attached manual for details. Figure 8 , 9: In this embodiment, the force measuring rod 3 is rotatably arranged on the rear side of the C-type fuselage through a force measuring rod bracket, and the force measuring rod 3 and the force measuring rod bracket are rotatably connected through a bearing. At the same time, a force sensor 8 is fixedly arranged on the rear side of the C-type fuselage through a bracket; a force measuring head 3.2 is fixedly arranged on the side of the force measuring rod 3 close to the force sensor 8; when the rotational torque of the wheel hub bearing is transmitted to the outer end of the force measuring rod 3 through the flange connecting ear 4.2.1 of the flange outer ring 4.2, the force measuring rod 3 is pushed to rotate, so that the force measuring head 3.2 is abutted against the force sensor 8, and the rotary riveting rotational torque between the flange inner ring 4.1 and the flange outer ring 4.2 is measured by the force sensor 8; in this embodiment, the torque measuring device can amplify the thrust transmitted to the force measuring rod 3 by the flange connecting ear 4.2.1, so as to obtain better measurement sensitivity.

[0068] The wheel hub bearing spin riveting assembly clearance control method of the second embodiment adopts the spin riveting rotation torque M feedback control spin riveting head position working mode, and this control mode is applied to the spin riveting assembly machine that adopts the servo motor to control the feed and pressure control of the spin riveting head 1; in the wheel hub bearing spin riveting assembly clearance control method of this embodiment, the first spin riveting assembly section spin riveting rotation torque M1, the maximum spin riveting rotation torque M M , Standard rotation torque m s The control range test method is basically the same as that of the first embodiment, except that: in the first riveting assembly section, the maximum riveting rotation torque M1 test is performed. M In the experiment, the position of the rivet head in the original wheel hub bearing rivet assembly process parameters was adjusted. The adjustment amount of the rivet head position each time was 3-5 times the position control accuracy of the rivet assembly machine.

[0069] The following describes in detail the spin riveting assembly process of the wheel hub bearing using the position control mode; the spin riveting rotation torque M1 of the first spin riveting assembly stage is 3.9 Nm, and the maximum spin riveting rotation torque M M is 4.5Nm; control chart of mean standard deviation of free rotation torque m The upper control line UCL is 1.2Nm, the lower control line LCL is 1.12Nm, and the center value is 1.16Nm;

[0070] When the hub bearing 4 is riveted, the hub bearing is fixedly arranged on the riveting turntable assembly 2, and the flange connection ear 4.2.1 contacts the outer end of the force measuring rod 3; the riveting head 1 rotates clockwise at a speed of 540r / min, and the feed speed is 1.0mm / s; the turntable 2.1 drives the flange inner ring 4.1 to rotate clockwise at a speed of 180r / min, and the flange outer ring 4.2 remains stationary; the speed difference between the riveting head 1 and the flange inner ring 4.1 is 360r / min (the speed difference is the speed of the riveting head of the original hub bearing 4 riveting assembly, and the other riveting process parameters are the same as the original hub bearing 4 riveting assembly process parameters), that is, the actual riveting speed of the riveting head 1 is 360r / min;

[0071] As the rivet head 1 is fed into the first rivet assembly section, the rivet head 1 contacts the flange inner ring rivet joint 4.1.1, and the rivet head 1 continuously presses the flange inner ring rivet joint 4.1.1 at the set feed speed and rivet rotation speed, causing it to undergo plastic deformation of flipping outward and pressing on the upper end face of the small inner ring 4.3; in this process, as the pressure of the rivet head 1 gradually increases, the plastic deformation of the flange inner ring rivet joint 4.1.1 also increases synchronously, and at the same time, the pressure on the upper end face of the small inner ring 4.3 also gradually increases, resulting in an increase in the negative clearance of the wheel hub bearing 4, so that the rivet rotation torque between the flange inner ring 4.1 and the flange outer ring 4.2 also gradually increases; the measuring rod 3 The measuring bridge continuously measures the rivet rotation torque between the flange inner ring 4.1 and the flange outer ring 4.2. When the measured rivet rotation torque reaches the rivet rotation torque M13.9Nm of the first rivet assembly section, feedback control is used to lock the position of the rivet head 1. The rivet head 1 continues to work for 0.67s in the locked position (i.e., the rivet head 1 spins 4 circles) to complete the plastic deformation of the rivet joint 4.1.1 of the inner ring of the rivet flange, and then the rivet head is lifted by 1.0mm. After the rivet head 1 is lifted and depressurized, if the free rotation torque m of the hub bearing 4 falls between the upper control line UCL of 1.2Nm and the lower control line LCL of 1.12Nm, the hub bearing 4 rivet assembly is completed.

[0072] After the rivet head 1 is lifted and depressurized in the first riveting assembly section, if the free rotation torque m of the hub bearing 4 is less than 1.12Nm of the lower control line LCL, the second riveting assembly section is carried out; in the second riveting assembly section, the riveting rotation torque M2 of the hub bearing 4 increases to 4.02Nm by 20% of the riveting rotation torque range (4.5-3.9=0.6Nm), that is, in the second riveting assembly section, when the measured riveting rotation torque M2 reaches 4.02Nm, the feedback control locks the position of the rivet head 1, and then the riveting is continued for 0.67s, and the rivet head is lifted by 1.0mm; after the rivet head 1 is lifted and depressurized, if the free rotation torque m of the hub bearing 4 falls between 1.2Nm of the upper control line UCL and 1.12Nm of the lower control line LCL, the riveting assembly of the hub bearing 4 is completed;

[0073] After the rivet head 1 is lifted and depressurized in the second rivet assembly section, if the free rotation torque m of the hub bearing 4 is still less than 1.12Nm of the lower control line LCL, the third rivet assembly section is carried out; in the third rivet assembly section, the rivet rotation torque M2 of the hub bearing 4 increases to 4.14Nm by 20% of the rivet rotation torque range (4.5-3.9=0.6Nm), that is, in the third rivet assembly section, when the measured rivet rotation torque M2 reaches 4.14Nm, the feedback control locks the position of the rivet head 1, and then the rivet is continuously performed for 0.67s, and the rivet head is lifted by 1.0mm; after the rivet head 1 is lifted and depressurized, if the free rotation torque m of the hub bearing 4 falls between 1.2Nm of the upper control line UCL and 1.12Nm of the lower control line LCL, the rivet assembly of the hub bearing 4 is completed;

[0074] Starting from the fourth riveting assembly stage, the riveting rotation torque M of the hub bearing 4 N The torque range of the riveting rotation is increased by 10% (4.5-3.9=0.6Nm), that is, 0.06Nm is increased each time;

[0075] By analogy, after the seventh riveting assembly section is completed, even if the free rotation torque m of the hub bearing 4 is still less than 1.12Nm of the lower control line LCL, the riveting assembly of the hub bearing 4 is also completed; but at this time, the hub bearing 4 is judged as a defective product and the cause of the defect needs to be analyzed.

[0076] Supplementary explanation: When the pressure control mode is adopted, the reason why the rotary riveting assembly section is provided with the rotary riveting leveling is that when the rotary riveting head 1 causes the flange inner ring rivet joint 4.1.1 to undergo plastic deformation under the action of the locked constant pressure, although theoretically the hardening resistance after plastic deformation is sufficient to resist the continued deformation under the locked constant pressure, in fact, the flange inner ring rivet joint 4.1.1 may still have continuous plastic deformation during the constant pressure spinning process, resulting in parallelism deviation of the riveted surface after rotary riveting, so it is necessary to reduce the locking pressure to perform rotary riveting leveling; while in the position control mode, when the position of the rotary riveting head 1 is locked unchanged, as the flange inner ring rivet joint 4.1.1 undergoes plastic deformation during the spinning process, the pressure of the rotary riveting head 1 on the flange inner ring rivet joint 4.1.1 naturally decreases, so there is no need to increase the rotary riveting leveling.

[0077] The parts not described in detail in this invention are prior art.

[0078] Those skilled in the art should understand that they can implement variations by combining the prior art and the above embodiments. Such variations do not affect the essence of the present solution and are not described in detail here.

[0079] It should be understood that the present solution is not limited to the above-mentioned specific implementation methods, and the devices and structures not described in detail should be understood to be implemented in a common manner in the art; any technician familiar with the art can use the above-disclosed methods and technical contents to make many possible changes and modifications to the technical solution of the present solution without departing from the scope of the technical solution of the present solution, or modify it into an equivalent embodiment with equivalent changes, which does not affect the essential content of the present solution. Therefore, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present solution without departing from the content of the technical solution of the present solution still falls within the scope of protection of the technical solution of the present solution.

Claims

1. A method for controlling clearance of a hub bearing spin riveting assembly, wherein a spin riveting assembly machine used for the hub bearing spin riveting assembly comprises a machine body, a spin riveting head, a spin riveting turntable assembly, and a torque measuring device, wherein the spin riveting head is rotatably arranged on the upper side of the machine body, and the feed or pressure of the spin riveting head is controlled by servo; the spin riveting turntable assembly is rotatably arranged on the lower side of the machine body; the torque measuring device is arranged on the side of the spin riveting turntable assembly; when the hub bearing is spin riveted, the spin riveting head and the spin riveting turntable assembly rotate in the same direction, the rotation speed of the spin riveting turntable assembly is less than the rotation speed of the spin riveting head, and the spin riveting head feeds downward at the same time, thereby completing the spin riveting assembly of the hub bearing; Its characteristics are: During the spin riveting assembly of the wheel hub bearing, the torque measuring device detects the spin riveting rotation torque M during the spin riveting assembly of the wheel hub bearing and the free rotation torque m after the spin riveting head is lifted; the spin riveting pressure or position of the spin riveting head is controlled by feedback of the spin riveting rotation torque M, and whether the spin riveting assembly of the wheel hub bearing is completed is determined by checking whether the free rotation torque m falls within the control range; The wheel hub bearing spin riveting assembly process includes more than one spin riveting assembly section, and each spin riveting assembly section is set with a standard spin riveting rotation torque M. n In each riveting assembly section, the riveting rotation torque M is detected to see whether it reaches the standard riveting rotation torque M of that section. n Feedback control locks the pressure or position of the rivet head; when the rivet rotation torque M of the wheel hub bearing reaches the standard rivet rotation torque M of this section n When the riveting pressure is locked, continue to rivet for a certain period of time, then reduce the riveting pressure, rivet flatten for a certain period of time, lift the riveting head to unload the riveting pressure; or when the riveting rotation torque M of the wheel hub bearing reaches the standard riveting rotation torque M of this section n When the riveting head is locked, the riveting head is kept in position for a certain period of time, and the riveting head is lifted to unload the riveting pressure. If the free rotation torque m detected in a certain riveting assembly section is less than the standard rotation torque m s When the control range reaches the lower limit, continue to the next riveting assembly section until the free rotation torque m is detected to fall within the standard rotation torque m. s When it is within the control range, the hub bearing riveting assembly is completed; Or riveting torque M n Reach the maximum setting value M M At this time, the wheel hub bearing riveting assembly is completed.

2. The wheel hub bearing riveting assembly clearance control method according to claim 1 is characterized by: The rotation torque of the first riveting assembly section is M1, and the standard rotation torque of each subsequent riveting assembly section is M1. n Increase successively until the maximum setting value M M .

3. The wheel hub bearing riveting assembly clearance control method according to claim 2 is characterized by: Wheel hub bearing standard rotation torque m s The method is as follows: select several hub bearings that have been riveted and assembled and are within the negative clearance range required by the standard, divide them into several groups, measure their free rotation torque m at the set speed, make a mean standard deviation control chart mS of the free rotation torque m, and use the upper control line UCL and the lower control line LCL of the mean standard deviation control chart mS of the free rotation torque m as the standard rotation torque m s Control scope.

4. The wheel hub bearing riveting assembly clearance control method according to claim 3 is characterized by: The riveting rotation torque M1 of the first riveting assembly section of the wheel hub bearing is measured experimentally by the following method: S5.

1. Using the original wheel hub bearing riveting assembly process parameters, several wheel hub bearings are divided into several groups and riveted on a riveting assembly machine for riveting assembly experiments; during the riveting assembly experiment, the wheel hub bearing riveting rotation torque M' and the free rotation torque m' are detected and recorded; the mean values ​​M' of the riveting rotation torques of several groups are calculated; and the mean standard deviation control chart m'-S of the free rotation torque m' is made; S5.

2. Compare the mean standard deviation control chart m′-S of the free rotation torque m′ with the mean standard deviation control chart mS of the free rotation torque m. If the upper control line UCL′ of the mean standard deviation control chart m′-S of the free rotation torque m′ is greater than the upper control line UCL of the mean standard deviation control chart mS of the free rotation torque m, modify the rivet head pressure or position parameters in the original wheel hub bearing rivet assembly process parameters, and conduct the wheel hub bearing rivet assembly experiment again; S5.3, repeat the above steps until the upper control line UCL′ of the mean standard deviation control chart m′-S of the free rotation torque m′ is equal to or less than the upper control line UCL of the mean standard deviation control chart mS of the free rotation torque m. At this time, the mean values ​​M′ of several groups of rotary rivet rotation torques are used as the rotary rivet rotation torque M1 of the first rotary rivet assembly section of the wheel hub bearing.

5. The wheel hub bearing riveting assembly clearance control method according to claim 3 is characterized by: Wheel hub bearing maximum riveting torque M M The method is measured by experiment: S6.

1. Using the original wheel hub bearing riveting assembly process parameters, several wheel hub bearings are divided into several groups and riveted on a riveting assembly machine for riveting assembly experiments. During the riveting assembly experiment, the wheel hub bearing riveting rotation torque M′ and the free rotation torque m′ are detected and recorded; the mean values ​​of the riveting rotation torques M′ of several groups are calculated; and the mean standard deviation control chart m′-S of the free rotation torque m′ is made; S6.

2. Compare the mean standard deviation control chart m′-S of the free rotation torque m′ with the mean standard deviation control chart mS of the free rotation torque m. If the lower control line LCL′ of the mean standard deviation control chart m′-S of the free rotation torque m′ is less than the lower control line LCL of the mean standard deviation control chart mS of the free rotation torque m, modify the rivet head pressure or position parameters in the original wheel hub bearing rivet assembly process parameters, and conduct the wheel hub bearing rivet assembly experiment again; S6.3, repeat the above steps until the lower control line LCL' of the mean standard deviation control chart m'-S of the free rotation torque m' is equal to or greater than the lower control line LCL of the mean standard deviation control chart mS of the free rotation torque m, at this time, the mean value M' of several groups of spin riveting rotation torques is taken as the maximum spin riveting rotation torque M of the hub bearing. M .

6. The wheel hub bearing riveting assembly clearance control method according to claim 4 or 5, characterized in that: The standard riveting torque M set for each subsequent riveting assembly stage n+1 , compared with the standard rivet rotation torque M set in the previous rivet assembly section n , in increments of 5-20% of the riveting torque range.

7. A riveting assembly machine based on the wheel hub bearing riveting assembly clearance control method according to claim 1, characterized in that: The torque measuring device comprises a force measuring rod fixedly arranged on the rear side of the fuselage, and four resistance strain gauges fixedly pasted on the vertical surfaces on both sides of the force measuring rod.

8. A riveting assembly machine based on the wheel hub bearing riveting assembly clearance control method according to claim 1, characterized in that: The torque measuring device includes a force measuring rod rotatably arranged on the rear side of the fuselage, and a force measuring sensor fixedly arranged on the rear side of the fuselage. A force measuring head is fixedly arranged on the side of the force measuring rod close to the end of the fuselage. When the torque measuring device detects the rotary riveting torque of the wheel hub bearing, the force measuring head contacts the force measuring sensor.

9. The rotary riveting assembly machine according to claim 7 or 8, characterized in that: The rotary riveting turntable assembly includes a turntable, a positioning column, and a pressure block. The positioning column is fixedly arranged on the upper surface of the turntable, and the pressure block is movably arranged on the upper surface of the turntable. A bearing box assembly is fixedly arranged at the lower part of the rotary riveting turntable assembly. The rotary riveting turntable assembly is driven by the main shaft in the bearing box assembly to rotate; the main shaft is directly driven to rotate by the turntable motor, or the turntable motor and the main shaft are connected by a synchronous belt drive; or the turntable motor and the main shaft are connected by gear meshing drive.

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