A rivet nut assembly precision detection device and detection method

Abstract

The present application relates to the rivet nut internal thread detection technical field, especially relates to a kind of rivet nut assembly precision detection device and detection method, including basic base plate, clamping device and detection device are equipped on basic base plate.Justification rivet nut, ensure that position remains unchanged during detection process, and detection device is used to detect the assembly precision of rivet nut.The present application drives driving disc to rotate forward, and the elastic deformation of volute spring is compressed to drive hollow sleeve to rotate detection rod to rotate, detects screw rod and rivet nut internal thread cooperation, judges assembly precision by the elastic force change of volute spring, that is, according to the size of rivet nut internal thread gap reflected by the amount of volute spring stress change.

Description

Technical Field

[0001] The present 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] Rivet nuts, as important fasteners, play an indispensable role in numerous industrial fields, particularly in aviation, machinery, and electronics. Their primary purpose is to connect and secure components by attaching bolts or other fasteners to rivets, which have internally threaded holes. In many fastener applications, the quality of the rivet nut's internal threads directly determines the robustness and reliability of the entire component. Therefore, ensuring the machining accuracy and surface quality of the rivet nut's internal threads is crucial.

[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 pushing assembly is used to push 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 assembly 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, whether the internal thread of the nut meets the established standard is evaluated by detecting the thread fit between the screw and the nut. 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 threads are matched, the screw and the nut may become loose.

[0005] Based on this, the above existing technologies cannot meet the requirements of high-precision assembly, resulting in safety hazards and unstable performance in actual 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:

[0008] A clamping device is assembled on the base plate, and the clamping device includes two sets of clamping side plates, and a plurality of clamping members are provided between the two sets of clamping side plates for carrying and clamping rivet nuts;

[0009] The detection device is arranged above the clamping device, and includes multiple sets of hollow sleeves corresponding to the clamping members one by one. A driving disk is provided on the outer side of the hollow sleeve, and a volute spring is provided between the hollow sleeve and the driving disk. When the driving disk rotates, the volute spring drives the hollow sleeve to rotate. 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;

[0010] The lifting device is assembled on the base plate and is located on 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.

[0011] 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 transmission, a protective shell is detachably installed on the lower end of the driving disk, and a volute spring is arranged in the protective shell.

[0012] Preferably, one end of the spiral spring can be detachably mounted on the hollow sleeve, and the other end can be detachably mounted on the supporting cylinder, and the end of the supporting cylinder facing the driving disk has a slider, and a sliding groove is opened on the driving disk along the radial direction, and the slider can be detachably mounted in the sliding groove and slides in the sliding groove.

[0013] Preferably, the driving disk has multiple sliding grooves, and the multiple sliding grooves are distributed on the driving disk at equal intervals in the circumferential direction. The distances between the ends of the sliding grooves close to the edge of the driving disk and the hollow sleeve are different. A scale bar is provided on one side of each sliding groove to measure the sliding distance of the slider in the sliding groove.

[0014] 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 sliding groove.

[0015] Preferably, the driving disk and the hollow sleeve are connected through a ratchet pawl transmission. When the detection rod is detecting, the driving 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 driving disk rotates reversely to drive the hollow sleeve to rotate reversely through the ratchet pawl, and the volute spring does not work.

[0016] Preferably, the bottom of the detection rod is detachably connected to a detection screw, and the assembly accuracy of the rivet nut is detected by cooperating between the detection screw and the internal thread of the rivet nut; the top of the detection rod is threadedly connected to an extension rod, and the top of the extension rod is provided with a rod cap.

[0017] Preferably, a through hole is opened at the position corresponding to the hollow sleeve of the horizontal mounting plate, and a mounting sleeve is detachably mounted on the through hole. A cylinder cover is mounted on the top of the mounting sleeve, and a rotating shaft is rotatably passed through the middle of the cylinder cover. An electromagnet is mounted at the lower end of the rotating shaft and below the cylinder cover. When the electromagnet is energized, the rod cap is attracted to move upward.

[0018] 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. When the telescopic end of the elastic telescopic rod contacts the pre-pressing plate, downward pressure is applied to the pre-pressing plate.

[0019] In a second aspect, a method for detecting the assembly accuracy of rivet nuts is provided, the detection method comprising the following steps:

[0020] The first step is to place the rivet nut to be tested on the clamping member so that the rivet nut is clamped between the two sets of clamping side plates by the clamping member;

[0021] In the second step, the detection device is driven downward by the lifting device so that the detection rod is accurately aligned with the internal threaded hole of the rivet nut. Then the driving disk is driven to rotate. Under the action of the scroll spring, the hollow sleeve drives the detection rod to slowly screw into the internal threaded hole of the rivet nut.

[0022] The third step is that after the test is completed, the drive disc 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;

[0023] The fourth step is to judge 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 part is released from the rivet nut, the rivet nut that has been tested is taken out, and the qualified and unqualified rivet nuts are classified and stored.

[0024] In summary, this application has the following beneficial technical effects:

[0025] 1. The present invention drives the driving disk to rotate in the forward direction, and the scroll spring is compressed and elastically deformed, thereby driving the hollow sleeve to rotate and the detection rod to rotate accordingly. The detection screw cooperates with the internal thread of the rivet nut, and the assembly accuracy is judged by the change in 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 in the force of the scroll spring.

[0026] Second, when the electromagnet is energized, the present invention generates a magnetic force that attracts the detection rod, causing the detection screw to tend to move upward, thereby simulating the pulling state between the detection screw and the rivet nut during the actual assembly process, so as 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 gradually separates from the rivet nut, so that the detection screw has a stable pulling force during the separation process. The double verification mechanism ensures the assembly accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The present invention will be further described below with reference to the accompanying drawings and examples.

[0028] Figure 1 It is a structural schematic diagram of the present invention.

[0029] Figure 2 This is a schematic diagram of the structure of the detection device of the present invention Figure 1 .

[0030] Figure 3 This is a schematic diagram of the structure of the detection device of the present invention Figure 2 .

[0031] Figure 4 This is a schematic diagram of the structure of the detection device of the present invention Figure 3 .

[0032] Figure 5 This is a schematic diagram of the structure of the detection device of the present invention Figure 4 .

[0033] Figure 6 It is a schematic structural diagram of the detection rod, detection screw and rod cap of the present invention.

[0034] Figure 7 This invention Figure 2 A partial enlarged view of point A in the middle.

[0035] Figure 8 It is a structural schematic diagram of the lifting device of the present invention.

[0036] Figure 9 It is a schematic structural diagram of the clamping device of the present invention.

[0037] Figure 10 This invention Figure 9 A partial enlarged view of point B in the middle.

[0038] Figure 11 It is a side view of the clamping member of the present invention.

[0039] In the figure, 1. base plate; 2. clamping device; 20. clamping side plate; 21. clamping member; 211. clamping plate; 212. clamping rod; 213. synchronization plate; 214. electric push rod; 215. limit plate; 216. adjustment screw; 217. extension bar; 218. adjustment plate; 219. sliding hole; 220. bidirectional screw; 3. detection device; 30. transverse mounting plate; 300. hollow sleeve; 301. drive disc; 302. volute spring; 303. detection rod; 304. drive ring; 305. protective shell; 306 307, support cylinder; 308, slide; 309, scale bar; 310, displacement sensor; 311, detection screw; 312, stud; 313, extension rod; 314, rod cap; 315, mounting sleeve; 316, cylinder cover; 317, rotating shaft; 318, electromagnet; 319, preload plate; 320, elastic telescopic rod; 321, annular cover; 322, cushion; 4, lifting device; 401, lifting frame; 402, lifting plate; 403, lifting screw; 404, guide rod; 405, guide bar. 50, rivet nut; 501, annular outer edge. DETAILED DESCRIPTION

[0040] The following combination Figures 1-11 The embodiments of the present invention are described in detail.

[0041] Example 1: Reference Figure 1 As shown, a rivet nut assembly accuracy detection device includes a base plate 1, on which are provided a clamping device 2 and a detection device 3. The clamping device 2 is responsible for stabilizing the rivet nut 50 to ensure that it remains in position during the detection process, while the detection device 3 is used to detect the assembly accuracy of the rivet nut 50.

[0042] Specifically, the clamping device 2 is assembled on the base 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.

[0043] Reference Figures 2 to 4As shown, the detection device 3 is disposed above the clamping device 2 and includes multiple sets of hollow sleeves 300 corresponding one-to-one with the clamping members 21. The hollow sleeves 300 are constructed as an annular cylindrical structure with a hollow interior. A drive disk 301 is sleeved on the outer side of the hollow sleeve 300. The drive disk 301 is constructed in a circular structure. An annular cover plate 321 is provided on the upper sidewall of the hollow sleeve 300. The lower surface of the annular cover plate 321 is in rotational contact with the upper surface of the drive disk 301. A scroll spring 302 is disposed between the hollow sleeve 300 and the drive disk 301. When the drive disk 301 rotates, the scroll spring 302 drives the hollow sleeve 300 to rotate. The change in the force on the scroll spring 302 is used to determine the fit accuracy of the internal thread of the rivet nut 50. The scroll spring 302 generates an elastic force under the action of the drive disk 301, which then drives the hollow sleeve 300 to rotate, thereby achieving accurate measurement of the internal thread of the rivet nut 50.

[0044] 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 detection screw 311 and the internal thread of the rivet nut 50.

[0045] The driving disc 301 and the hollow sleeve 300 are connected via a ratchet and pawl transmission.

[0046] When the detection rod 303 is detecting, the drive disk 301 rotates in the forward direction, the ratchet pawl does not work, and the hollow sleeve 300 rotates through the spiral spring 302. 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 spiral spring 302 will change accordingly, and the rotational resistance of the drive 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 spiral spring 302.

[0047] When the detection rod 303 is reset, the drive disk 301 rotates in the opposite direction, the spiral spring 302 stops working, the ratchet pawl starts working, driving the hollow sleeve 300 to rotate in the opposite direction, and the detection rod 303 drives the detection screw 311 to disengage from the internal thread of the rivet nut 50, achieving rapid reset.

[0048] 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.

[0049] See 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. At the same time, a pin is provided on the side wall at the bottom of the detection rod 303 to penetrate into the stud 312. 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 facilitates the subsequent replacement of detection screws 311 of different specifications to meet the detection requirements of various rivet nuts 50.

[0050] See Figure 2 and Figure 4 As shown, the detection device 3 also includes a transverse mounting plate 30, and a drive ring 304 is installed on the upper end of the drive disk 301. The drive ring 304 is rotatably mounted on the bottom of the transverse mounting plate 30. All the drive rings 304 are connected by belt transmission. The belt transmission is driven by a drive motor (not shown in the figure). After the motor is started, it drives the drive ring 304 to rotate synchronously, and then drives all the drive disks 301 to rotate, so that multiple groups of rivet nuts 50 can be detected at the same time, thereby improving the detection efficiency.

[0051] The driving motor is provided with a variable frequency speed regulation function, which can adjust the speed according to the detection requirements of different rivet nuts 50, and the driving motor has a forward and reverse rotation function. By controlling the forward and reverse rotation of the motor, the detection and reset operations of the detection rod 303 are realized, ensuring the flexibility and accuracy of the detection process.

[0052] Reference Figures 2 to 4 As shown, a protective housing 305 is removably mounted at the lower end of the drive disk 301, housing the scroll spring 302. This housing effectively prevents damage to the spring and facilitates maintenance and replacement. Furthermore, the housing is made of a transparent rubber material, specifically polycarbonate, to facilitate observation of the internal structure and ensure safe operation. The housing is also designed with heat dissipation holes (not shown) to prevent overheating of the scroll spring 302 during prolonged operation, thereby extending its service life.

[0053] The drive disc 301 is detachably mounted on the drive ring 304, facilitating routine maintenance and replacement. Made of a high-strength alloy, the drive disc 301 ensures durability and stability. A shock-absorbing pad (not shown) is positioned between the drive ring 304 and the transverse mounting plate 30 to reduce vibration during operation and improve detection accuracy.

[0054] Because during the inspection process 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 driving disk 301, the end of the spiral spring 302 away from the hollow sleeve 300 is radially slidably arranged on the driving disk 301.

[0055] Reference Figure 5Specifically, one end of the scroll spring 302 is detachably mounted on the hollow sleeve 300, and the other end is detachably mounted on the support cylinder 306. The support cylinder 306 has a slider 307 on the end facing the drive disk 301. A radial groove 308 is defined on the drive disk 301, and the slider 307 is detachably mounted within and slides within the groove 308. This ensures that the scroll spring 302 can freely extend and retract under the drive disk 301. The coordinated design of the slider 307 and the groove 308 reduces frictional resistance, improving the response speed and detection accuracy of the scroll spring 302. The slider 307 is made of wear-resistant material, extending its service life and ensuring long-term stable operation.

[0056] A lubrication groove (not shown) is provided on the inner wall of the slide groove 308 , and the lubrication groove is filled with a special lubricant to further reduce friction, ensure smooth movement of the slider 307 , and improve overall detection efficiency.

[0057] Continue to refer to Figure 5 As shown, in addition, the driving disk 301 has multiple sliding grooves 308, and the multiple sliding grooves 308 are distributed on the driving disk 301 at equal intervals in the circumferential direction. The distances between one end of the sliding grooves 308 close to the edge of the driving disk 301 and the hollow sleeve 300 are different, and the sliding member can be detachably installed in one of the sliding grooves 308.

[0058] Initially, due to the elastic force of the volute 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 volute spring 302 to expand and contract. The deformation of the volute spring 302 generates a corresponding elastic force, driving the hollow sleeve 300 to rotate, thereby realizing accurate detection of the rivet nut 50.

[0059] 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 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 conform to 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, affecting the assembly accuracy of the rivet nut 50 and needs to be adjusted or replaced in time.

[0060] When the position of the slider 307 in the chute 308 is less than the preset standard scale, it indicates 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 internal thread size of the rivet nut 50 is too large, resulting in unstable assembly. Conversely, if the position is greater than the preset standard scale, the deformation of the scroll spring 302 is too large and the thread engagement is too tight, that is, the internal thread size of the rivet nut 50 is too small, which is prone to stress concentration during assembly, affecting the structural strength and requiring reprocessing or replacement to ensure assembly quality. Through this design, the quality of the internal thread of the rivet nut 50 is accurately detected, effectively avoiding assembly errors caused by thread problems and improving the assembly accuracy of the rivet nut 50.

[0061] 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 results.

[0062] Embodiment 2: The present invention only detects the degree of thread engagement between the screw 311 and the rivet nut 50 by the deformation degree of the scroll spring 302 and the position change of the slider 307, and judges 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 by only using 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 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 guaranteeing the assembly quality and assembly accuracy of the rivet nut 50.

[0063] 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.

[0064] 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 passed 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.

[0065] After the detection screw 311 is engaged with the rivet nut 50, the electromagnet 318 controls the rod cap 314 to move upward, driving the extension rod 313 and the detection rod 303 to reset, thereby driving 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 actual assembly.

[0066] When the electromagnet 318 is energized, it will generate a magnetic attraction force 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 engaged, 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 thread of the rivet nut 50. By observing the movement of the rod cap 314, the detection rod 303 or the detection screw 311, the quality of the thread engagement can be accurately judged.

[0067] 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, ensuring that each rivet nut 50 meets high-standard assembly requirements, thereby improving overall assembly efficiency and product quality.

[0068] 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 by 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 by disengaging from the internal thread of the rivet nut 50. The double verification mechanism further detects the engagement quality of the internal thread of the rivet nut 50.

[0069] 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 to improve the durability and stability of the equipment.

[0070] In addition, at the initial stage, when the driving disk 301 rotates in the forward direction, 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.

[0071] 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-load plate 319 downward to apply force, so that an initial pre-load is generated between the detection screw 311 and the rivet nut 50, ensuring smooth engagement, avoiding unstable engagement due to insufficient weight, and improving detection accuracy.

[0072] It should be noted that the mounting sleeve 315 and the cylinder cover 316 are both made of transparent materials, which facilitates observation of the internal structure and operating status, ensuring that the operator can monitor the dynamic changes of the rod cap 314 and the detection rod 303 in real time.

[0073] See Figure 1 As shown, further, the lifting device 4 is assembled on the base plate 1 and is located on one side of the clamping device 2 , and the detection device 3 is assembled on the lifting device 4 , and the longitudinal movement of the detection device 3 is controlled by the lifting device 4 .

[0074] See 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 403 is rotatably installed in the lifting frame 401 and is threadedly matched with the lifting plate 402.

[0075] The lifting frame 401 can be detachably mounted on the base plate 1 , and two groups of lifting screw rods 403 are provided, and the lower ends of both groups are rotated and passed through the bottom of the base plate 1 , and the bottoms of the two groups of lifting screw rods 403 are connected by a chain drive.

[0076] 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 and contacts the electromagnet 318. At this time, the rivet nut 50 to be inspected is placed on the clamping part 21, and the clamping part 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 rebound force 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.

[0077] 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 depends entirely on its own structure, ensuring a stable detection process.

[0078] During the detection process, the operator can observe the relative position changes between the rod cap 314 and the detection rod 303 in real time through the transparent installation sleeve 315 and the cylinder cover 316 to determine whether the engagement state is normal.

[0079] See Figure 8 As shown, a plurality of guide rods 404 with equal spacing are rotatably passed through the lifting frame 401, and the lifting plate 402 is slidably passed through the guide rods 404. The inner side walls of the two side plates of the lifting frame 401 are provided with guide slides 405. Sliding holes that slide with the guide slides 405 are opened at both ends of the lifting plate 402. The guide rods 404 ensure that the lifting plate 402 moves smoothly to avoid deflection.

[0080] Example 3: See Figures 9 to 11 As shown, on the basis of Example 1 and Example 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. 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, ensuring that the rivet nut 50 and the detection screw 311 are on the same axis.

[0081] The two clamping plates 211 are connected to the back sides with clamping rods 212, and the clamping rods 212 slide through the clamping side plates 20. The rivet nut 50 is placed between the two clamping plates 211. By driving the clamping rods 212, the two clamping plates 211 can be moved relative to each other, thereby clamping the rivet nut 50 between the two clamping plates 211.

[0082] Synchronizing plates 213 are installed on opposite sides of the two clamping side plates 20. The end of the clamping rod 212, facing away from the clamping plate 211, is connected to the synchronizing plate 213. An electric push rod 214 is connected between the synchronizing plate 213 and the clamping side plates 20. The electric push rod 214 controls the movement of the synchronizing plate 213 to achieve synchronized expansion and contraction of the two clamping rods 212, ensuring a balanced clamping force of the clamping plates 211 on the rivet nut 50 and avoiding detection errors caused by uneven clamping. The stroke of the electric push rod 214 is adjustable to accommodate rivet nuts 50 of different sizes, improving detection flexibility and accuracy.

[0083] 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 surface of the two clamping plates 211, so that the bottom of the rivet nut 50 does not contact the base plate 1, that is, the rivet nut 50 is in a suspended state. In this way, the present invention can carry out load clamping and internal thread detection for rivet nuts 50 of different lengths.

[0084] 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 from the horizontal plate is used to abut the upper surface of the annular outer edge 501 of the rivet nut 50. The limit plate 215 can be adjusted in 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, with its horizontal section parallel to the horizontal plate and its vertical section close to the vertical plate. The horizontal section of the limit plate 215 extends from a section of the horizontal plate to apply a stable limiting force to the annular outer edge 501 of the rivet nut 50, preventing the rivet nut 50 from deflecting during the detection process and ensuring detection accuracy.

[0085] 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. This means that the annular outer edge 501 of the rivet nut 50 must be supported by both the limiting plate 215 and the upper surface of the clamping plate 211. This increases the difficulty of initial placement and requires precise alignment of the upper surfaces of both. To address this issue, the present invention provides an extension bar 217 extending from the lower surface of the horizontal plate that holds the side plate 20. The extension bar 217 is used to support the lower surface of the annular outer edge 501 of the rivet nut 50. The extension bar 217 is separated at the limiting plate 215 to be staggered with the limiting plate 215.

[0086] During initial placement, the annular outer edge 501 of the rivet nut 50 is first placed on the two extension bars 217, and then the rivet nut 50 is pushed along the length of the extension bar 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, achieving precise positioning. This design not only simplifies the placement process of the rivet nut 50, but also ensures its stability during testing, further improving the efficiency and accuracy of testing. The clever combination of the extension bar 217 and the limit plate 215 makes operation more convenient, reduces human error, and reflects the practicality and innovation of the present invention.

[0087] 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 an upward movement tendency 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 is carried out smoothly.

[0088] Adjustment plates 218 are provided on the undersides of both ends of the clamping side plates 20. Sliding holes 219 are provided on the base plate 1 for the adjustment plates 218 to move. A bidirectional screw 220 is threadedly connected to the bottoms of the two adjustment plates 218 on the same side of the two sets of clamping side plates 20. In other words, the two adjustment plates 218 are threadedly connected to the ends of the bidirectional screw 220. The bidirectional screw 220 is rotatably mounted on a base provided at the lower end of the base plate 1. A handle is provided at one end of the bidirectional screw 220. By rotating the handle, the bidirectional screw 220 drives the adjustment plates 218 to move synchronously, thereby precisely adjusting the spacing between the clamping side plates 20 to accommodate rivet nuts 50 of different sizes.

[0089] In addition, the present application also provides a method for detecting the assembly accuracy of rivet nuts, which includes the following steps:

[0090] In the first step, the rivet nut 50 to be inspected is placed on the clamping member 21 so as to clamp the rivet nut 50 between the two sets of clamping side plates 20 through the clamping member 21 .

[0091] In the second step, the detection device 3 is driven downward by the lifting device 4 so that the detection rod 303 is accurately aligned 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 scroll 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 scroll 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.

[0092] 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 exit the internal threaded hole of the rivet nut 50, and the lifting device 4 drives the detection device 3 to move upward and reset.

[0093] The fourth step is to determine whether the quality of the internal thread of the corresponding rivet nut 50 is qualified based on the deformation of the scroll spring 302. At the same time, the clamping of the rivet nut 50 by the clamping member 21 is released, the rivet nut 50 that has been tested is taken out, and the qualified and unqualified rivet nuts 50 are classified and stored.

[0094] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention. Therefore, the embodiments should be considered in all respects as exemplary and non-restrictive.

[0095] In addition, it should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This narrative method 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 can also be appropriately combined to form other implementation methods 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 assembled on the base plate (1), the clamping device (2) comprising two sets of clamping side plates (20), and a plurality of clamping members (21) are provided between the two sets of clamping side plates (20); The detection device (3) is arranged above the clamping device (2), and includes a plurality of hollow sleeves (300) corresponding to the clamping members (21). A driving disk (301) is provided on the outer side of the hollow sleeve (300). A volute spring (302) is provided 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. A detection rod (303) is slidably inserted into the hollow sleeve (300). A lifting device (4) is mounted on the base plate (1) and is located on one side of the clamping device (2); and a detection device (3) is mounted on the lifting device (4); 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 within the protective housing (305); 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); A through hole is formed in the horizontal mounting plate (30) corresponding to the hollow sleeve (300), a mounting sleeve (315) is mounted on the through hole, a cylinder cover (316) is mounted on the top of the mounting sleeve (315), a rotating shaft (317) is rotatably passed through the middle of the cylinder cover (316), and an electromagnet (318) is mounted at the lower end of the rotating shaft (317) and below the cylinder cover (316); 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).

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

3. The rivet nut assembly accuracy detection device according to claim 2, 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). The distances 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).

4. The rivet nut assembly accuracy detection device according to claim 2, characterized in that: A displacement sensor (310) is provided on the side of the supporting cylinder (306) facing the hollow sleeve (300).

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

6. A method for detecting assembly accuracy of rivet nuts, using the rivet nut assembly accuracy detection device according to any one of claims 1 to 5, characterized in that: The detection method includes the following steps: In the first step, the rivet nut to be tested is placed on the clamping member (21) 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 threaded hole of the rivet nut, and then drives the driving disk (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 threaded hole of the rivet nut; In the third step, after the detection is completed, the driving disc (301) rotates in the opposite direction, the hollow sleeve (300) drives the detection rod (303) to exit the inner 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, the quality of the internal thread of the rivet nut is judged to be qualified according to the deformation 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 after the inspection is taken out.

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