Rivet nut assembly precision detection device and detection method

Abstract

The invention relates to the technical field of rivet nut internal thread detection, in particular to a rivet nut assembly precision detection device and method, and the device comprises a foundation bottom plate which is provided with a clamping device and a detection device. The clamping device is responsible for stabilizing the rivet nut and ensuring that the position is kept unchanged in the detection process, and the detection device is used for detecting the assembly precision of the rivet nut. The driving disc is driven to rotate in the forward direction, the volute spiral spring is stressed and compressed to generate elastic deformation, the hollow sleeve is driven to rotate, the detection rod rotates along with the hollow sleeve, the detection screw is matched with the rivet nut internal thread, the assembly precision is judged through the elastic force change of the volute spiral spring, and the size of the rivet nut internal thread gap is reflected according to the stress change quantity of the volute spiral spring.

Description

Technical Field

[0001] The invention relates to the technical field of rivet nut internal thread detection, and in particular to a rivet nut assembly accuracy detection device and a detection method. Background Art

[0002] As an important fastener, rivet nuts play an indispensable role in many industrial fields, especially in the aviation, machinery, electronics and other industries. Its main purpose is to connect and fix components by fixing bolts or other fasteners on rivets with threaded holes inside. In many fastener application scenarios, the quality of the internal threads of the rivet nuts directly determines the firmness and reliability of the entire component. Therefore, it is crucial to ensure the processing accuracy and surface quality of the internal threads of the rivet nuts.

[0003] However, some existing detection methods have some limitations in actual operation, such as a nut internal thread detection device with announcement number CN220083846U, which includes a mounting table, a pushing assembly, a detection assembly and two clamping assemblies for clamping multiple nuts; multiple nuts are placed between two limit plates, and then the pusher assembly pushes the multiple nuts toward the two connecting plates, and the nuts push the two connecting plates away from each other, so that the two limit plates press the two elastic support assemblies, and the resetting of the elastic support assemblies pushes the two clamping plates to clamp the nuts; then the controller controls the first telescopic device to push the detection device downward, and the detection device detects the internal thread of the nut.

[0004] In the above-mentioned prior art, the thread fit between the screw and the nut is detected to evaluate whether the internal thread of the nut meets the established standard. However, when there is a slight deviation in the thread size, even if the screw and the thread can be matched, there will be problems with assembly accuracy. For example, if the internal thread size of the nut is smaller than the established standard, the thread fit between the screw and the nut will become more difficult, and a larger torque will need to be applied to control the rotation of the screw, and the required rotational force will exceed the established value. On the contrary, if the internal thread size of the nut is larger than the established standard, the thread fit between the screw and the nut will become too easy, the required torque will be reduced, and after the thread fit, looseness may occur between the screw and the nut.

[0005] Based on this, the above-mentioned prior art cannot meet the high-precision assembly requirements, resulting in potential safety hazards and unstable performance problems in practical applications. Therefore, it is particularly important to develop a device that can accurately detect the assembly accuracy of rivet nuts. Summary of the invention

[0006] In order to solve the above problems, the present invention provides a rivet nut assembly accuracy detection device and detection method.

[0007] In a first aspect, a rivet nut assembly accuracy detection device includes a base plate and further includes: A clamping device is mounted on the base bottom plate, and the clamping device includes two sets of clamping side plates, and a plurality of clamping members are arranged between the two sets of clamping side plates for carrying and clamping rivet nuts; The detection device is arranged above the clamping device, and includes a plurality of hollow sleeves corresponding to the clamping members one by one. A driving disk is sleeved on the outer side of the hollow sleeve, and a volute spring is arranged between the hollow sleeve and the driving disk. When the driving disk rotates, the hollow sleeve is driven to rotate by the volute spring. A detection rod is slidably penetrated in the hollow sleeve, and the detection rod is used to detect the internal thread of the rivet nut; The lifting device is assembled on the base bottom plate and is located at one side of the clamping device. The detection device is assembled on the lifting device, and the longitudinal movement of the detection device is controlled by the lifting device.

[0008] Preferably, the detection device also includes a transverse mounting plate, a driving ring is installed on the upper end of the driving disk, the driving ring is rotatably installed on the bottom of the transverse mounting plate, all the driving rings are connected by belt drive, a protective shell is detachably installed on the lower end of the driving disk, and a volute spring is arranged in the protective shell.

[0009] Preferably, one end of the spiral spring can be removably mounted on the hollow sleeve, and the other end can be removably mounted on the supporting cylinder, and the end of the supporting cylinder facing the driving disk has a sliding block, and a sliding groove is opened on the driving disk along the radial direction, and the sliding block can be removably mounted in the sliding groove and slide in the sliding groove.

[0010] Preferably, the driving disk has a plurality of slide grooves, and the plurality of slide grooves are circumferentially evenly spaced on the driving disk, and the distances from one end of the slide grooves close to the edge of the driving disk to the hollow sleeve are different, and a scale bar is provided on one side of each slide groove to measure the sliding distance of the slider in the slide groove.

[0011] Preferably, a displacement sensor is provided on the side of the support cylinder facing the hollow sleeve, and the distance between the support cylinder and the hollow sleeve is measured by the displacement sensor to determine the sliding distance of the slider in the slide groove.

[0012] Preferably, the drive disk and the hollow sleeve are connected via a ratchet pawl transmission. When the detection rod is detecting, the drive disk rotates forward to drive the hollow sleeve to rotate forward through the volute spring, and the ratchet pawl does not work; when the detection rod is reset, the drive disk rotates reversely to drive the hollow sleeve to rotate reversely through the ratchet pawl, and the volute spring does not work.

[0013] Preferably, a detection screw is detachably connected to the bottom of the detection rod, and the assembly accuracy of the rivet nut is detected by the cooperation between the detection screw and the internal thread of the rivet nut; an extension rod is threadedly connected to the top of the detection rod, and a rod cap is provided on the top of the extension rod.

[0014] Preferably, a through hole is opened at the position corresponding to the hollow sleeve of the transverse mounting plate, and a mounting sleeve is detachably mounted on the through hole. A sleeve cover is mounted on the top of the mounting sleeve, and a rotating shaft is rotatably penetrated through the middle of the sleeve cover. An electromagnet is mounted at the lower end of the rotating shaft and below the sleeve cover. When the electromagnet is energized, the rod cap is attracted to move upward.

[0015] Preferably, a pre-pressing plate is rotatably mounted on the outer side wall of the rod cap, and an elastic telescopic rod is mounted on the top of the cylinder cover, and when the telescopic end of the elastic telescopic rod contacts the pre-pressing plate, downward pressure is applied to the pre-pressing plate.

[0016] In a second aspect, a method for detecting the assembly accuracy of a rivet nut is provided, the detection method comprising the following steps: The first step is to place the rivet nut to be tested on the clamping member so as to clamp the rivet nut between the two sets of clamping side plates through the clamping member; The second step is to drive the detection device downward through the lifting device so that the detection rod is accurately aligned with the internal thread hole of the rivet nut, and then drive the driving disk to rotate. Under the action of the scroll spring, the hollow sleeve drives the detection rod to slowly screw into the internal thread hole of the rivet nut; The third step is that after the detection is completed, the driving disk rotates in the opposite direction, the hollow sleeve drives the detection rod to exit the inner threaded hole of the rivet nut, and the lifting device drives the detection device to move up and reset; The fourth step is to determine whether the quality of the internal thread of the rivet nut is qualified based on the deformation of the scroll spring. At the same time, the clamping of the rivet nut by the clamp is released, the rivet nut that has been tested is taken out, and the qualified and unqualified rivet nuts are classified and stored.

[0017] In summary, this application includes the following beneficial technical effects: 1. The present invention drives the driving disk to rotate in the forward direction, and the scroll spring is compressed and elastically deformed, so as to drive the hollow sleeve to rotate and the detection rod rotates accordingly. The detection screw cooperates with the internal thread of the rivet nut, and the assembly accuracy is judged by the change of the elastic force of the scroll spring, that is, the size of the internal thread gap of the rivet nut is reflected according to the change of the force of the scroll spring.

[0018] 2. When the electromagnet is energized, the magnetic force generated by the present invention attracts the detection rod, so that the detection screw has a tendency to move upward, thereby simulating the pulling state of the detection screw and the rivet nut in the actual assembly process to further improve the detection accuracy of the assembly precision. At the same time, the driving disk rotates in the opposite direction, and with the cooperation of the ratchet pawl, the detection screw is gradually separated from the rivet nut, so that the detection screw has a stable pulling force during the separation process, and the double verification mechanism ensures the assembly accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0020] Figure 1 It is a structural schematic diagram of the present invention.

[0021] Figure 2 The structure of the detection device of the present invention is shown in FIG. Figure 1 .

[0022] Figure 3 The structure of the detection device of the present invention is shown in FIG. Figure 2 .

[0023] Figure 4 The structure of the detection device of the present invention is shown in FIG. Figure 3 .

[0024] Figure 5 The structure of the detection device of the present invention is shown in FIG. Figure 4 .

[0025] Figure 6 It is a schematic diagram of the structure among the detection rod, the detection screw rod and the rod cap of the present invention.

[0026] Figure 7 The present invention Figure 2 A partial enlarged view of point A in the middle.

[0027] Figure 8 It is a structural schematic diagram of the lifting device of the present invention.

[0028] Fig. 9 It is a schematic structural diagram of the clamping device of the present invention.

[0029] Fig.10 The present invention Fig. 9 A partial enlarged view of point B in the middle.

[0030] Fig.11 It is a side view of the clamping member of the present invention.

[0031] In the figure, 1, base plate; 2, clamping device; 20, clamping side plate; 21, clamping member; 211, clamping plate; 212, clamping rod; 213, synchronous plate; 214, electric push rod; 215, limit plate; 216, adjusting screw; 217, extension strip; 218, adjusting plate; 219, sliding hole; 220, bidirectional screw; 3, detection device; 30, horizontal mounting plate; 300, hollow sleeve; 301, driving disk; 302, scroll spring; 303, detection rod; 304, driving ring; 305, protective shell; 306 , support cylinder; 307, slider; 308, slide; 309, scale bar; 310, displacement sensor; 311, detection screw; 312, stud; 313, extension rod; 314, rod cap; 315, installation sleeve; 316, cylinder cover; 317, rotating shaft; 318, electromagnet; 319, pre-pressing plate; 320, elastic telescopic rod; 321, annular cover plate; 322, buffer pad; 4, lifting device; 401, lifting frame; 402, lifting plate; 403, lifting screw rod; 404, guide rod; 405, guide slide bar. 50, rivet nut; 501, annular outer edge. DETAILED DESCRIPTION

[0032] The following combination Figure 1-Figure 11 Embodiments of the present invention are described in detail.

[0033] Example 1: Reference Figure 1 As shown, a rivet nut assembly accuracy detection device includes a base plate 1, on which a clamping device 2 and a detection device 3 are provided. The clamping device 2 is responsible for stabilizing the rivet nut 50 to ensure that the position remains unchanged during the detection process, and the detection device 3 is used to detect the assembly accuracy of the rivet nut 50.

[0034] Specifically, the clamping device 2 is assembled on the base bottom plate 1, and the clamping device 2 includes two groups of clamping side plates 20. A plurality of clamping members 21 are provided between the two groups of clamping side plates 20 for carrying and clamping rivet nuts 50. The rivet nuts 50 are fixed between the two groups of clamping side plates 20 by the clamping members 21.

[0035] Reference Figures 2 to 4As shown, the detection device 3 is arranged above the clamping device 2, and the detection device 3 includes a plurality of hollow sleeves 300 corresponding to the clamping member 21. The hollow sleeve 300 is constructed as an annular cylinder structure with a hollow interior. A driving disk 301 is sleeved on the outer side of the hollow sleeve 300. The driving disk 301 is constructed as a circular structure. An annular cover plate 321 is provided on the upper side wall of the hollow sleeve 300. The lower surface of the annular cover plate 321 is in rotational contact with the upper surface of the driving disk 301. A volute spring 302 is arranged between the hollow sleeve 300 and the driving disk 301. When the driving disk 301 rotates, the hollow sleeve 300 is driven to rotate by the volute spring 302. The matching accuracy of the internal thread of the rivet nut 50 is judged by the change of the force of the volute spring 302. The volute spring 302 generates elastic force under the action of the driving disk 301, and then uses the elastic force to drive the hollow sleeve 300 to rotate, so as to achieve accurate measurement of the internal thread of the rivet nut 50.

[0036] A detection rod 303 is slidably inserted into the hollow sleeve 300, and the detection rod 303 is used to detect the internal thread of the rivet nut 50; a detection screw 311 is detachably connected to the bottom of the detection rod 303, and the assembly accuracy of the rivet nut 50 is detected by the cooperation between the detection screw 311 and the internal thread of the rivet nut 50.

[0037] The driving disc 301 and the hollow sleeve 300 are connected via a ratchet and pawl transmission.

[0038] When the detection rod 303 is detecting, the driving disk 301 rotates forward, the ratchet pawl does not work, and the hollow sleeve 300 rotates through the volute spring 302, and the detection rod 303 rotates accordingly, and the detection screw 311 begins to cooperate with the internal thread of the rivet nut 50. If the thread gap is too large or too small, the elastic force of the volute spring 302 will change accordingly, and the rotational resistance of the driving disk 301 will increase or decrease. The assembly accuracy of the rivet nut 50 can be obtained by the change in the elastic force of the volute spring 302.

[0039] When the detection rod 303 is reset, the drive disk 301 rotates in the opposite direction, the spiral spring 302 stops working, and the ratchet pawl starts working, driving the hollow sleeve 300 to rotate in the opposite direction. The detection rod 303 drives the detection screw 311 to disengage from the internal thread of the rivet nut 50, thereby achieving rapid reset.

[0040] The outer wall of the detection rod 303 is constructed as an external spline structure, which slides with the corresponding internal spline on the inner wall of the hollow sleeve 300 to ensure that the detection rod 303 can be driven to rotate synchronously when the hollow sleeve 300 rotates, while not affecting the axial sliding of the detection rod 303 in the hollow sleeve 300.

[0041] See also Figure 6As shown, further, a stud 312 is provided at the upper end of the detection screw 311, and a threaded hole is provided at the bottom of the detection rod 303 to be threadedly matched with the stud 312. The detection screw 311 is installed by the cooperation between the stud 312 and the threaded hole, and a pin is provided on the side wall at the bottom of the detection rod 303 to penetrate into the stud 312, and the pin is used to lock the stud 312 to prevent the detection screw 311 from loosening during the detection process. The detection screw 311 is installed through the stud 312, which is convenient for subsequent replacement of detection screws 311 of different specifications to meet the detection requirements of various rivet nuts 50.

[0042] See also Figure 2 and Figure 4 As shown, the detection device 3 also includes a transverse mounting plate 30, and a driving ring 304 is installed on the upper end of the driving disk 301. The driving ring 304 is rotatably installed at the bottom of the transverse mounting plate 30. All the driving rings 304 are connected by belt transmission. The belt transmission is driven by a driving motor (not shown in the figure). After the motor is started, it drives the driving ring 304 to rotate synchronously, and then drives all the driving disks 301 to rotate, so as to realize the simultaneous detection of multiple groups of rivet nuts 50 and improve the detection efficiency.

[0043] The driving motor is provided with a variable frequency speed regulation function, and the speed can be adjusted according to the detection requirements of different rivet nuts 50. The driving motor has a forward and reverse rotation function, and the detection and resetting operations of the detection rod 303 are realized by controlling the forward and reverse rotation of the motor, thereby ensuring the flexibility and accuracy of the detection process.

[0044] Reference Figures 2 to 4 As shown, a protective shell 305 is detachably mounted at the lower end of the driving disk 301, and the spiral spring 302 is arranged in the protective shell 305. The protective shell 305 effectively prevents the spring from being damaged and is convenient for maintenance and replacement. At the same time, the protective shell 305 is set to a transparent rubber material, specifically a polycarbonate material, which is convenient for observing the internal structure and ensuring safe operation. The protective shell 305 is designed with heat dissipation holes (not shown in the figure) to prevent the spiral spring 302 from overheating after long-term operation and extend its service life.

[0045] The drive disk 301 is detachably mounted on the drive ring 304, which is convenient for daily maintenance and replacement. The drive disk 301 is made of high-strength alloy material to ensure durability and stability. A shock-absorbing pad (not shown in the figure) is provided between the drive ring 304 and the transverse mounting plate 30 to reduce vibration during operation and improve detection accuracy.

[0046] Because during the inspection of the rivet nut 50, the elastic force generated by the winding deformation of the spiral spring 302 acts on the hollow sleeve 300 through the drive disk 301, so the end of the spiral spring 302 away from the hollow sleeve 300 is radially slidably arranged on the drive disk 301.

[0047] Reference Figure 5As shown, specifically, one end of the volute spring 302 is detachably mounted on the hollow sleeve 300, and the other end is detachably mounted on the support cylinder 306, and the support cylinder 306 has a slider 307 at one end facing the drive disk 301, and a slide groove 308 is provided on the drive disk 301 along the radial direction, and the slider 307 is detachably mounted in the slide groove 308 and slides in the slide groove 308. It is ensured that the volute spring 302 can be freely extended and retracted under the drive disk 301, and at the same time, the matching design of the slider 307 and the slide groove 308 reduces the friction resistance, and improves the response speed and detection accuracy of the volute spring 302. The slider 307 is made of wear-resistant material to extend the service life and ensure long-term stable operation.

[0048] A lubrication groove (not shown) is provided on the inner wall of the slide groove 308 , and a special lubricant is filled in the lubrication groove to further reduce friction, ensure smooth movement of the slider 307 , and improve overall detection efficiency.

[0049] Continue to refer to Figure 5 As shown, in addition, the driving disk 301 has a plurality of slide grooves 308, and the plurality of slide grooves 308 are evenly spaced circumferentially distributed on the driving disk 301, and the distances from one end of the slide grooves 308 close to the edge of the driving disk 301 to the hollow sleeve 300 are different, and the sliding part 308 can be detachably installed in one of the slide grooves 308.

[0050] Initially, due to the elastic force of the spiral spring 302, the slider 307 is in the starting position of the slide groove 308, that is, the slider 307 is at the end of the slide groove 308 away from the hollow sleeve 300. As the driving disk 301 rotates, the slider 307 gradually moves in the slide groove 308, driving the spiral spring 302 to expand and contract. The deformation of the spiral spring 302 generates a corresponding elastic force, driving the hollow sleeve 300 to rotate, thereby realizing accurate detection of the rivet nut 50.

[0051] A scale bar 309 is provided on one side of each slide groove 308 to measure the sliding distance of the slider 307 in the slide groove 308. The deformation amount of the scroll spring 302 depends on the degree of thread engagement between the detection screw 311 and the rivet nut 50. The scale bar 309 measures the position of the slider 307 in the slide groove 308. If the position of the slider 307 in the slide groove 308 does not match the preset standard scale, it indicates that there is a problem with the thread engagement, that is, the internal thread of the rivet nut 50 is unqualified, which affects the assembly accuracy of the rivet nut 50 and needs to be adjusted or replaced in time.

[0052] When the position of the slider 307 in the slide groove 308 is less than the preset standard scale, it means that the deformation of the scroll spring 302 is less than the preset value, indicating that the thread engagement is too loose, that is, the size of the internal thread of the rivet nut 50 is too large, resulting in unstable assembly; on the contrary, if the position is greater than the preset standard scale, the deformation of the scroll spring 302 is too large, the thread engagement is too tight, that is, the size of the internal thread of the rivet nut 50 is too small, and stress concentration is easily generated during assembly, affecting the structural strength, and reprocessing or replacement is required to ensure the assembly quality. Through this design, the quality of the internal thread of the rivet nut 50 is accurately detected, which effectively avoids assembly errors caused by thread problems and improves the assembly accuracy of the rivet nut 50.

[0053] A displacement sensor 310 is provided on the side of the support cylinder 306 facing the hollow sleeve 300. The displacement sensor 310 measures the distance between the support cylinder 306 and the hollow sleeve 300, thereby determining the sliding distance of the slider 307 in the slide groove 308 and evaluating the actual deformation of the scroll spring 302. At the same time, the reading of the scale bar 309 is referred to to achieve double verification of the thread engagement state, thereby ensuring the reliability and accuracy of the detection result.

[0054] Embodiment 2: The present invention detects the degree of thread engagement between the screw rod 311 and the rivet nut 50 only by the deformation degree of the scroll spring 302 and the position change of the slider 307, and determines whether the internal thread of the rivet nut 50 is qualified and whether the assembly accuracy meets the requirements. However, it is difficult to fully reflect the assembly accuracy under complex working conditions only by the deformation of the scroll spring 302 and the position of the slider 307. Therefore, on the basis of Embodiment 1, this embodiment pulls the detection rod 303 when the detection rod 303 moves up and resets to drive the engagement strength of the detection screw rod 311 and the rivet nut 50, further simulating the force conditions in the actual assembly process, ensuring the comprehensiveness and accuracy of the detection results, and thus more effectively ensuring the assembly quality and assembly accuracy of the rivet nut 50.

[0055] Reference Figure 6 As shown, specifically, the top of the detection rod 303 is threadedly connected with an extension rod 313, and the top of the extension rod 313 is provided with a rod cap 314. By pulling the rod cap 314, the extension rod 313 is driven to drive the detection rod 303 to move longitudinally.

[0056] Reference Figure 2 and Figure 7 As shown, a through hole is opened at the position corresponding to the hollow sleeve 300 of the horizontal mounting plate 30, and a mounting sleeve 315 is detachably mounted on the through hole. A cylinder cover 316 is mounted on the top of the mounting sleeve 315, and a rotating shaft 317 is rotatably penetrated through the middle of the cylinder cover 316. An electromagnet 318 is mounted at the lower end of the rotating shaft 317 and below the cylinder cover 316. The rod cap 314 is made of a magnetic material that can be attracted by the electromagnet 318, so that the electromagnet 318 attracts the rod cap 314 to move upward when power is supplied to it.

[0057] After the detection screw 311 is engaged with the rivet nut 50, the rod cap 314 is moved upward by the electromagnet 318 to drive the extension rod 313 and the detection rod 303 to reset, so as to generate a pulling force between the detection screw 311 and the rivet nut 50 to detect the engagement strength of the detection screw 311 and the rivet nut 50, simulating the force conditions in the actual assembly.

[0058] When the electromagnet 318 is energized, it will generate a magnetic attraction on the rod cap 314, driving it to move upward. Under normal circumstances, although the rod cap 314 has a tendency to move upward, the detection screw 311 and the rivet nut 50 are in a meshing state, and the upward movement of the rod cap 314 is hindered and cannot move upward smoothly. If the detection screw 311 and the rivet nut 50 are not tightly meshed, the rod cap 314 will move upward under the action of the magnetic attraction, and axial sliding will occur between the detection screw 311 and the rivet nut 50, thereby exposing the defects of the internal threads of the rivet nut 50. By observing the movement of the rod cap 314, the detection rod 303 or the detection screw 311, the thread engagement quality can be accurately judged.

[0059] In this way, not only can thread defects be effectively identified, but also subtle changes in the assembly process can be monitored in real time to ensure that each rivet nut 50 meets high-standard assembly requirements, thereby improving overall assembly efficiency and product quality.

[0060] When the electromagnet 318 is energized, the detection screw 311 tends to move upward, and the driving disk 301 rotates in the opposite direction. The hollow sleeve 300 is driven to rotate in the opposite direction through the ratchet pawl, so that the detection screw 311 rotates in the opposite direction synchronously. The detection screw 311 begins to disengage from the internal thread of the rivet nut 50, and when the electromagnet 318 is energized to drive the rod cap 314 to move upward, the detection screw 311 has a pulling force to move upward while the detection screw 311 disengages from the internal thread of the rivet nut 50. The double verification mechanism further detects the meshing quality of the internal thread of the rivet nut 50.

[0061] When the electromagnet 318 is powered off and the detection screw 311 is disengaged from the rivet nut 50, under the action of gravity, the detection rod 303, the detection screw 311, the extension rod 313 and the rod cap 314 fall down and reset in sequence. A buffer pad 322 is provided on the upper end of the hollow sleeve 300, and the rod cap 314 falls onto the buffer pad 322, which can effectively absorb the impact force of the fall and avoid mechanical damage. The buffer pad 322 is preferably made of rubber material to improve the durability and stability of the equipment.

[0062] In addition, at the initial stage, when the driving disk 301 rotates forward, the hollow sleeve 300 is driven to rotate synchronously through the spiral spring 302. The detection rod 303 slides axially in the hollow sleeve 300. In the initial engagement stage, the detection screw 311 and the rivet nut 50 may not be initially engaged smoothly due to the deadweight of the detection rod 303, the detection screw 311, the extension rod 313 and the rod cap 314. Therefore, a pre-load plate 319 is rotatably installed on the outer wall of the rod cap 314, and an elastic telescopic rod 320 is installed on the top of the cylinder cover 316. When the telescopic end of the elastic telescopic rod 320 contacts the pre-load plate 319, it exerts downward pressure on the pre-load plate 319.

[0063] During the initial engagement, the rod cap 314 is at the highest point, that is, it is in contact with the electromagnet 318. At this time, the elastic telescopic rod 320 is compressed and contracts, pushing the pre-compression plate 319 downward to apply force, so that an initial pre-compression force is generated between the detection screw 311 and the rivet nut 50, ensuring smooth engagement, avoiding unstable engagement due to insufficient dead weight, and improving detection accuracy.

[0064] It should be noted that the installation sleeve 315 and the cylinder cover 316 are both made of transparent materials, which is convenient for observing the internal structure and operating status, and ensures that the operator can monitor the dynamic changes of the rod cap 314 and the detection rod 303 in real time.

[0065] See also Figure 1 As shown, further, the lifting device 4 is mounted on the base plate 1 and is located on one side of the clamping device 2 , and the detection device 3 is mounted on the lifting device 4 , and the longitudinal movement of the detection device 3 is controlled by the lifting device 4 .

[0066] See also Figure 8 As shown, the lifting device 4 includes a lifting frame 401, a lifting plate 402 is longitudinally slidably provided in the lifting frame 401, a transverse mounting plate 30 is installed on one side of the lifting plate 402, and a lifting screw rod 403 is rotatably installed in the lifting frame 401 and is threadedly matched with the lifting plate 402.

[0067] The lifting frame 401 is detachably mounted on the base bottom plate 1 , and two groups of lifting screw rods 403 are provided, and the lower ends of both groups of lifting screw rods 403 are rotated and penetrated under the base bottom plate 1 , and the bottoms of the two groups of lifting screw rods 403 are connected by chain transmission.

[0068] When preparing to inspect the rivet nut 50, the electromagnet 318 is energized to drive the rod cap 314, the inspection rod 303, and the inspection screw 311 to move upward until the rod cap 314 moves up to contact with the electromagnet 318. At this time, the rivet nut 50 to be inspected is placed on the clamping member 21, and the clamping member 21 clamps the rivet nut 50. The motor connected to one of the lifting screw rods 403 is started, and the other lifting screw rod 403 is driven to rotate synchronously through the chain drive. The lifting plate 402 moves downward with the lifting screw rod 403 until the lower end of the inspection screw 311 contacts the rivet nut 50. Then the electromagnet 318 is de-energized, and the rod cap 314 is acted upon by gravity and the resilience of the elastic telescopic rod 320, giving the inspection screw 311 an initial pre-pressure to ensure that it is tightly engaged with the rivet nut 50.

[0069] After completing the preliminary preparations, start the motor connected to the drive ring 304, and the drive disk 301 rotates forward, driving the scroll spring 302 to rotate, and then driving the hollow sleeve 300 and the detection rod 303 to rotate synchronously. As the detection screw 311 gradually penetrates and engages with the rivet nut 50, the increase in the engagement depth causes the contact between the elastic telescopic rod 320 and the pre-loaded plate 319 to be disconnected. At this time, the engagement of the detection screw 311 and the rivet nut 50 completely relies on its own structure to ensure the stability of the detection process.

[0070] During the detection process, the operator can observe the relative position change between the rod cap 314 and the detection rod 303 in real time through the installation sleeve 315 and the tube cover 316 made of transparent material to determine whether the meshing state is normal.

[0071] See also Figure 8 As shown, a plurality of guide rods 404 equidistantly distributed are rotatably penetrated in the lifting frame 401, and the lifting plate 402 is slidably penetrated on the guide rods 404. Guide slide bars 405 are provided on the inner side walls of the two side plates of the lifting frame 401. Sliding holes slidably matched with the guide slide bars 405 are provided at both ends of the lifting plate 402. The guide rods 404 ensure that the lifting plate 402 moves smoothly to avoid deflection.

[0072] Example 3: See Figures 9 to 11 As shown, on the basis of Embodiment 1 and Embodiment 2, the clamping member 21 is further optimized. Specifically, the clamping side plate 20 is an inverted L-shaped structure composed of a horizontal plate and a vertical plate, and the clamping member 21 includes two symmetrically distributed clamping plates 211. Each clamping plate 211 is provided with an anti-slip pad on the inner side. The clamping plate 211 preferably has a V-shaped structure to enhance the stable clamping force on the rivet nut 50 and to achieve the technical effect of centering adjustment when clamping the rivet nut 50, thereby ensuring that the rivet nut 50 and the detection screw 311 are on the same axis.

[0073] The two clamping plates 211 are connected to the back sides thereof with clamping rods 212 , and the clamping rods 212 are slidably passed through the clamping side plates 20 . The rivet nut 50 is placed between the two clamping plates 211 . The two clamping plates 211 are moved relative to each other by driving the clamping rods 212 , thereby clamping the rivet nut 50 between the two clamping plates 211 .

[0074] The two clamping side plates 20 are provided with a synchronous plate 213 on the opposite sides, and the end of the clamping rod 212 away from the clamping plate 211 is connected to the synchronous plate 213, and an electric push rod 214 is connected between the synchronous plate 213 and the clamping side plate 20. The electric push rod 214 controls the movement of the synchronous plate 213 to achieve the synchronous extension and contraction of the two clamping rods 212, ensure the balanced clamping force of the clamping plate 211 on the rivet nut 50, and avoid the detection error caused by uneven clamping. The stroke of the electric push rod 214 is adjustable to adapt to rivet nuts 50 of different sizes, thereby improving the flexibility and accuracy of detection.

[0075] Since the upper end of the rivet nut 50 has a protruding annular outer edge 501, when the rivet nut 50 is placed, the annular outer edge 501 of the rivet nut 50 will be supported on the upper surfaces of the two clamping plates 211, so that the bottom of the rivet nut 50 does not contact the base bottom plate 1, that is, the rivet nut 50 is in a suspended state, so that the present invention can carry out clamping and internal thread detection of rivet nuts 50 of different lengths.

[0076] A plate groove corresponding to the clamping plate 211 is provided on the horizontal plate of the clamping side plate 20, and a limit plate 215 is longitudinally slidably installed in the plate groove. The limit plate 215 is threadedly connected to the clamping side plate 20 through an adjusting screw 216. The end of the limit plate 215 extending out of the horizontal plate is used to abut against the upper surface of the annular outer edge 501 of the rivet nut 50. The limit plate 215 can adjust the position according to the thickness of the annular outer edge 501 of the rivet nut 50 to ensure accurate positioning of the annular outer edge 501 of the rivet nut 50. The limit plate 215 is constructed as an inverted L-shaped structure, the horizontal section of which is parallel to the horizontal plate, and the vertical section is close to the vertical plate. The horizontal section of the limit plate 215 extends out of the horizontal plate to apply a stable limiting force to the annular outer edge 501 of the rivet nut 50 to prevent the rivet nut 50 from deviating during the detection process and ensure the detection accuracy.

[0077] Initially, the rivet nut 50 is placed between the horizontal section of the limiting plate 215 and the upper surface of the clamping plate 211, that is, the annular outer edge 501 of the rivet nut 50 needs to be supported by both the limiting plate 215 and the upper surface of the clamping plate 211, which increases the difficulty of initial placement and requires precise alignment of the upper surfaces of the two. To solve this problem, the present invention provides an extension bar 217 extending from the horizontal plate on the lower surface of the horizontal plate of the clamping side plate 20, and the extension bar 217 is used to support the lower surface of the annular outer edge 501 of the rivet nut 50, and the extension bar 217 is separated at the limiting plate 215 to be staggered with the limiting plate 215.

[0078] During initial placement, the annular outer edge 501 of the rivet nut 50 is first placed on the two extension strips 217, and then the rivet nut 50 is pushed to move along the length direction of the extension strip 217 toward the limit plate 215 until the annular outer edge 501 of the rivet nut 50 slides between the horizontal section of the limit plate 215 and the upper surface of the clamping plate 211 to achieve precise positioning. This design not only simplifies the placement process of the rivet nut 50, but also ensures its stability during detection, further improving the detection efficiency and accuracy. The clever coordination of the extension strip 217 and the limit plate 215 makes the operation more convenient, reduces human errors, and reflects the practicality and innovation of the present invention.

[0079] It should be noted that the present invention supports the annular outer edge 501 of the rivet nut 50 on the upper surface of the clamping plate 211, so that the contact between the detection screw 311 and the internal thread of the rivet nut 50 during the initial engagement is smoother and more stable; and the limit plate 215 provided in the present invention is used for the detection screw 311 to have a tendency to move upward when the electromagnet 318 is energized, and the horizontal section of the limit plate 215 limits the axial movement of the rivet nut 50, ensuring that the axial stretching of the detection screw 311 and the internal thread of the rivet nut 50 proceeds smoothly.

[0080] Adjustment plates 218 are provided at the lower sides of both ends of the clamping side plates 20, and sliding holes 219 for the adjustment plates 218 to move are provided on the base bottom plate 1. A bidirectional screw rod 220 is threadedly connected between the bottoms of the two adjustment plates 218 on the same side of the two sets of clamping side plates 20, that is, the two adjustment plates 218 are threadedly connected to the two ends of the bidirectional screw rod 220, and the bidirectional screw rod 220 is rotatably installed on a base provided at the lower end of the base bottom plate 1. A handle is provided at one end of the bidirectional screw rod 220. By rotating the handle, the bidirectional screw rod 220 drives the adjustment plates 218 to move synchronously, thereby accurately adjusting the spacing between the clamping side plates 20 to adapt to rivet nuts 50 of different sizes.

[0081] In addition, the present application also provides a rivet nut assembly accuracy detection method, the detection method comprising the following steps: In the first step, the rivet nut 50 to be inspected is placed on the clamping member 21 , so that the rivet nut 50 is clamped between the two sets of clamping side plates 20 by the clamping member 21 .

[0082] In the second step, the detection device 3 is driven downward by the lifting device 4 to accurately align the detection rod 303 with the internal threaded hole of the rivet nut 50, and then the driving disk 301 is driven to rotate. Under the action of the volute spring 302, the hollow sleeve 300 drives the detection rod 303 to slowly screw into the internal threaded hole of the rivet nut 50. By observing the deformation of the volute spring 302, the depth and resistance of the detection rod 303 are judged, and then the quality of the internal thread of the rivet nut 50 is judged.

[0083] In the third step, after the detection is completed, the driving disk 301 rotates in the opposite direction, the hollow sleeve 300 drives the detection rod 303 to withdraw from the internal threaded hole of the rivet nut 50, and the lifting device 4 drives the detection device 3 to move up and reset.

[0084] The fourth step is to determine whether the quality of the internal thread of the corresponding rivet nut 50 is qualified according to the deformation of the scroll spring 302, and at the same time release the clamping of the rivet nut 50 by the clamping member 21, take out the inspected rivet nut 50, and classify and store the qualified and unqualified rivet nuts 50.

[0085] It is obvious 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 present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be considered as exemplary and non-restrictive in all respects.

[0086] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A rivet nut assembly accuracy detection device, comprising a base plate (1), characterized in that: Also includes: A clamping device (2) is mounted on the base bottom plate (1), the clamping device (2) comprising two groups of clamping side plates (20), and a plurality of clamping members (21) are arranged between the two groups of clamping side plates (20); The detection device (3) is arranged above the clamping device (2), and comprises a plurality of groups of hollow sleeves (300) corresponding one to one with the clamping members (21). A driving disk (301) is sleeved on the outer side of the hollow sleeve (300), and a volute spring (302) is arranged between the hollow sleeve (300) and the driving disk (301). When the driving disk (301) rotates, the volute spring (302) drives the hollow sleeve (300) to rotate, and a detection rod (303) is slidably inserted into the hollow sleeve (300); The lifting device (4) is mounted on the base plate (1) and is located on one side of the clamping device (2), and the detection device (3) is mounted on the lifting device (4).

2. A rivet nut assembly accuracy detection device according to claim 1, characterized in that: The detection device (3) further comprises a transverse mounting plate (30), a driving ring (304) being mounted on the upper end of the driving disk (301), the driving ring (304) being rotatably mounted on the bottom of the transverse mounting plate (30), all the driving rings (304) being connected by a belt transmission, a protective housing (305) being mounted on the lower end of the driving disk (301), and a volute spring (302) being disposed in the protective housing (305).

3. A rivet nut assembly accuracy detection device according to claim 1, characterized in that: One end of the spiral spring (302) is mounted on the hollow sleeve (300), and the other end is mounted on the supporting cylinder (306), and one end of the supporting cylinder (306) facing the driving disk (301) has a sliding block (307), a sliding groove (308) is provided on the driving disk (301) along a radial direction, and the sliding block (307) is mounted in the sliding groove (308) and slides in the sliding groove (308).

4. A rivet nut assembly accuracy detection device according to claim 3, characterized in that: The driving disk (301) has a plurality of slide grooves (308), and the plurality of slide grooves (308) are circumferentially distributed at equal intervals on the driving disk (301), and the intervals between one end of the plurality of slide grooves (308) close to the edge of the driving disk (301) and the hollow sleeve (300) are different, and a scale bar (309) is provided on one side of each slide groove (308).

5. The rivet nut assembly accuracy detection device according to claim 3, characterized in that: A displacement sensor (310) is provided on the side of the supporting cylinder (306) facing the hollow sleeve (300).

6. A rivet nut assembly accuracy detection device according to claim 1, characterized in that: The driving disk (301) and the hollow sleeve (300) are connected via a ratchet pawl transmission. During detection, the driving disk (301) rotates in the forward direction, and the hollow sleeve (300) is driven to rotate in the forward direction via the spiral spring (302), and the ratchet pawl does not work. During reset, the driving disk (301) rotates in the reverse direction, and the hollow sleeve (300) is driven to rotate in the reverse direction via the ratchet pawl, and the spiral spring (302) does not work.

7. A rivet nut assembly accuracy detection device according to claim 2, characterized in that: The bottom of the detection rod (303) is connected to a detection screw rod (311), the top of the detection rod (303) is threadedly connected to an extension rod (313), and the top of the extension rod (313) is provided with a rod cap (314).

8. A rivet nut assembly accuracy detection device according to claim 7, characterized in that: A through hole is formed in the transverse mounting plate (30) at a position corresponding to the hollow sleeve (300), a mounting sleeve (315) is mounted on the through hole, a sleeve cover (316) is mounted on the top of the mounting sleeve (315), a rotating shaft (317) is rotatably penetrated through the middle of the sleeve cover (316), and an electromagnet (318) is mounted at the lower end of the rotating shaft (317) and below the sleeve cover (316).

9. A rivet nut assembly accuracy detection device according to claim 8, characterized in that: A pre-pressing plate (319) is rotatably mounted on the outer wall of the rod cap (314), and an elastic telescopic rod (320) is mounted on the top of the cylinder cover (316). When the telescopic end of the elastic telescopic rod (320) contacts the pre-pressing plate (319), downward pressure is applied to the pre-pressing plate (319).

10. A method for detecting the assembly accuracy of a rivet nut, using a rivet nut assembly accuracy detection device according to any one of claims 1 to 9, characterized in that: The detection method includes the following steps: The first step is to place the rivet nut to be tested on the clamping member (21) so as to clamp the rivet nut between the two sets of clamping side plates (20); In the second step, the lifting device (4) drives the detection device (3) to move downward so that the detection rod (303) is aligned with the internal thread hole of the rivet nut, and then drives the driving plate (301) to rotate. Under the action of the scroll spring (302), the hollow sleeve (300) drives the detection rod (303) to be screwed into the internal thread hole of the rivet nut; In the third step, after the detection is completed, the driving disk (301) rotates in the opposite direction, the hollow sleeve (300) drives the detection rod (303) to withdraw from the internal threaded hole of the rivet nut, and the lifting device (4) drives the detection device (3) to move upward and reset; In the fourth step, whether the quality of the internal thread of the rivet nut is qualified is determined based on the deformation amount of the scroll spring (302), and at the same time, the clamping of the rivet nut by the clamping member (21) is released, and the rivet nut that has been tested is taken out.

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