Grounding combined bolt and nut assembly, tightening detection device and tightening detection process

Abstract

The present application relates to the technical field of bolt and nut tightening detection, and discloses a grounding combined bolt and nut assembling, tightening, detecting equipment and a tightening and detecting process, which comprises a placing platform, a rotating platform arranged on the placing platform, a nut placing hole arranged on the disc of the rotating platform, a tightening station, a detecting station, a lifting adjusting module, a rotating bolt module and a vibration detecting module. Through the cooperation of multiple stations, the present application can automatically complete the whole-process operation of nut feeding, bolt pre-tightening, torque tightening, vibration detection and finished product discharging, thereby improving the assembly and detection efficiency, screening out products with unqualified pre-tightening force in advance through vibration, ensuring that the grounding combined bolt and nut leaving the factory will not be loosened and dropped during transportation, avoiding the problems of missing parts and customer secondary assembly, and effectively improving the use experience of the product.

Description

Technical Field

[0001] This invention relates to the field of bolt and nut tightening testing technology, and more specifically to a grounding combination bolt and nut assembly tightening testing equipment and tightening testing process. Background Technology

[0002] In grounding construction in fields such as power and rail transportation, grounding components are assembled and connected by bolts and nuts. The reliability of the grounding connection directly determines the safety performance of the grounding system. After the bolts and nuts are produced, they are screwed together and sold as a product.

[0003] Currently, most bolt and nut tightening on the market is done in one step, with a certain torque applied to prevent the bolts and nuts from coming loose during transportation. However, in the actual bolt and nut tightening process, sometimes the bolts and nuts become loose, causing the finished products sold to easily separate and lose bolts or nuts during transportation, affecting the user experience. Therefore, a special equipment that can complete assembly and tightening and simultaneously perform quality inspection is needed to solve the existing problems. Summary of the Invention

[0004] To overcome the aforementioned deficiencies of the prior art, this invention provides a grounding combination bolt and nut assembly tightening detection device and tightening detection process to solve the problem that during transportation, the bolts and nuts are very easy to separate due to transportation vibration, resulting in the finished products not only requiring secondary assembly by the customer, but also easily losing nuts or bolts during transportation, affecting the user experience.

[0005] This invention provides the following technical solution: a grounding combination bolt and nut assembly tightening testing device, comprising: a placement platform, on which a turntable is provided, and a nut placement hole is provided on the disc of the turntable for placing the nut; a tightening station, located on the placement platform, for tightening the bolt and nut and applying torque; a testing station, located on the placement platform, behind the tightening station, for testing the bolt and nut tightened together; a lifting adjustment module, located in the tightening station and testing station, installed on the placement platform, and equipped with a mounting frame; a rotating bolt module, located in the tightening station and testing station, installed on the mounting frame, for driving the bolt to rotate; and a vibration testing module, located in the testing station, for performing vibration testing on the installed bolt and nut.

[0006] As a further embodiment of the present invention, the rotating bolt module includes: a rotating frame, rotatably mounted on the top of the mounting frame; a lifting frame, slidably mounted inside the rotating frame and only slidably connected to the rotating frame, the bottom of the lifting frame having a bolt insertion hole and the top having a turntable fixedly mounted thereon; a first spring, disposed between the lifting frame and the rotating frame; an external air pipe, installed on the top of the lifting frame and connected to the bolt insertion hole through an air passage; and a drive assembly, disposed on the mounting frame, for driving the rotating frame to rotate.

[0007] As a further embodiment of the present invention, the driving component includes: a support frame, fixedly mounted on the top of the mounting frame, and a servo motor fixedly mounted on the top of the support frame; a first gear, rotatably mounted on the top of the mounting frame, connected to the output shaft of the servo motor, and driven by the servo motor; and a second gear, fixedly mounted on the outside of the rotating frame, meshing with the first gear.

[0008] As a further embodiment of the present invention, the rotary bolt module located in the tightening station further includes: a first touch switch, which is fixedly installed on the top of the mounting bracket and used in conjunction with the turntable; a torque sensor, which is fixedly installed on one side of the support bracket, with its input end fixed to the output shaft of the servo motor and its output end fixed to the first gear, and the torque sensor is used in conjunction with the first touch switch.

[0009] As a further embodiment of the present invention, the rotating bolt module located in the testing station also includes: a second touch switch, which is fixedly installed above the mounting bracket and used in conjunction with the turntable to control the start and stop of the servo motor in the testing station.

[0010] As a further embodiment of the present invention, the vibration detection module includes: an electric push rod, installed on one side of the lifting adjustment module, with a guide frame fixedly installed at the movable end of the electric push rod, and a clearance groove extending through the top of the guide frame; a detection frame, disposed in the clearance groove and connected to the guide frame via a second spring, with a placement groove on the top of the detection frame, the placement groove having the same shape as the nut placement hole; a vibration motor, fixedly installed below the detection frame, for driving the vibration of the detection frame; a first distance sensor, installed on one side of the lifting adjustment module, with its detection end facing the bolt placed in the placement groove; and a second distance sensor, fixedly installed at the bottom of the mounting frame, with its detection end facing the bolt placed in the placement groove, the first distance sensor and the second distance sensor being used in conjunction.

[0011] As a further embodiment of the present invention, the vibration detection module further includes: a socket, which is provided on both sides of the bottom of the detection frame; and an electromagnetic lock, which is fixedly installed on the bottom of the guide frame and used in conjunction with the socket.

[0012] As a further embodiment of the present invention, the lifting adjustment module includes: a fixed base, which is fixedly installed on the placement platform, an electric push rod fixed to one side of the fixed base, and a guide frame slidably installed with the fixed base; a linear module, which is fixedly installed on one side of the fixed base, a slide is fixedly installed on the mover of the linear module, the slide is slidably installed with the fixed base, and the slide is fixed to the mounting frame.

[0013] A process for testing the tightening of grounding combination bolts and nuts includes the following steps: Step 1: When bolt and nut assembly and tightening operations are required, the turntable drives the pre-tightened bolts and nuts from the bolt loading and pre-tightening station to the tightening station. The lifting and adjusting module drives the mounting frame and rotating bolt module to descend, so that the rotating bolt module covers the head of the pre-tightened bolt. Step 2: The rotating bolt module drives the bolt to rotate, assembling the bolt and nut. After assembly, the rotating bolt module outputs the set torque to tighten the bolt into the corresponding nut and output a stable preset preload force. Step 3: After the tightening operation is completed, the rotating bolt module stops rotating, the lifting and adjusting module drives the rotating bolt module to rise and reset, and the turntable rotates to send the tightened bolts and nuts into the inspection station; Step 4: In the testing station, the rotating bolt module descends, driving the assembled bolts and nuts, and sending the bolts and nuts into the vibration testing module; Step 5: The vibration detection module is activated to perform vibration detection on the assembled bolts and nuts; Step Six: After the vibration ends, the rotating bolt module drives the bolt and nut out of the vibration detection module. The detection sensor determines whether the bolt and nut have become loose. Qualified products are output to the unloading station as the turntable rotates, while unqualified products are sorted and rejected separately, completing the entire assembly tightening and detection process.

[0014] The technical effects and advantages of this invention are as follows: 1. This invention, through the coordinated use of multiple workstations, can automatically complete the entire process of nut loading, bolt pre-tightening, torque tightening, vibration detection, and finished product unloading. This not only improves the efficiency of assembly and inspection, but also allows for the early screening of products with unqualified pre-tightening force through vibration, ensuring that the grounding combination bolts and nuts will not loosen or fall off during transportation, avoiding the problem of lost parts, and effectively improving the user experience of the product.

[0015] 2. This invention utilizes the elasticity of the spring to maintain a constant pressure output during tightening, ensuring that the bolt and the lifting frame remain in close contact during the tightening process.

[0016] 3. This invention utilizes a torque sensor in conjunction with a first touch switch. When the bolt head contacts the nut, it contacts the first touch switch and triggers a signal. At this time, the torque sensor starts working. When the torque sensor detects the predetermined torque, it controls the servo motor to stop running, completing the tightening operation. This accurately controls the preload and avoids loosening during transportation due to insufficient preload.

[0017] 4. The present invention uses a first distance sensor and a second distance sensor in combination to detect the positional change of the bolt head before and after vibration in both radial and axial directions. If the positional change exceeds a preset threshold, it can be determined that the preload of the bolt and nut is unqualified and it will be rejected by the subsequent sorting mechanism. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the overall structure of the device of the present invention.

[0019] Figure 2 This is a three-dimensional structural diagram of the present invention.

[0020] Figure 3 This is an enlarged schematic diagram of the overall structure of the tightening station of the present invention.

[0021] Figure 4 This is an enlarged structural diagram of the rotating bolt module in the tightening station of the present invention.

[0022] Figure 5 For the present invention Figure 4 A schematic diagram of a localized explosion structure.

[0023] Figure 6 This is a cross-sectional view of the lifting frame of the present invention.

[0024] Figure 7 This is a magnified schematic diagram of the overall structure of the detection station of the present invention.

[0025] Figure 8 This is a schematic diagram of the structure of the first distance sensor and the second distance sensor of the present invention.

[0026] Figure 9 This is an enlarged structural schematic diagram of the rotating bolt module in the testing station of the present invention.

[0027] Figure 10 This is a magnified structural diagram of the vibration detection module of the present invention.

[0028] Figure 11 This is an enlarged schematic diagram of the detection frame structure of the present invention.

[0029] Figure 12 This is a schematic diagram of the enlarged structure of the electromagnetic lock of the present invention.

[0030] The attached diagram is labeled as follows: 1. Placement platform; 2. Turntable; 3. Tightening station; 4. Inspection station; 5. Nut placement hole; 6. Lifting and adjusting module; 7. Mounting bracket; 8. Rotary bolt module; 9. Torque sensor; 10. First touch switch; 11. First distance sensor; 12. Second distance sensor; 13. Vibration detection module; 14. Second touch switch; 601. Fixed base; 602. Linear module; 603. Carriage; 801. Support frame; 802. Servo motor; 803. First gear; 804. Second gear; 805. Lifting frame; 806. Rotating frame; 807. Turntable; 808. External air pipe; 809. First spring; 810. Bolt hole; 811. Air passage; 1301 Electric push rod; 1302 Guide frame; 1303 Alternating groove; 1304 Second spring; 1305 Detection frame; 1306 Vibration motor; 1307 Electromagnetic lock; 1308 Socket; 1309 Placement groove; 1310 Slide groove; 1311 Elastic rubber pad. Detailed Implementation

[0031] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. In addition, the forms of the various structures described in the following embodiments are merely illustrative. The present invention is not limited to the structures described in the following embodiments. All other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0032] Reference Figures 1-12 This invention provides a grounding combination bolt and nut assembly tightening testing device, which solves the problem that bolts and nuts are easily separated during transportation due to vibration. This results in customers needing to reassemble the finished product, and nuts or bolts are easily lost during transportation, affecting the user experience. The device mainly consists of a placement platform 1 and multiple workstations, as detailed below: A turntable 2 (a conventional electric rotary worktable that can drive the workstations to rotate and switch sequentially at preset angles) is set on the placement platform 1. The disc of the turntable 2 is provided with nut placement holes 5 for placing nuts. Nut loading station, bolt loading and pre-tightening station, tightening station 3, inspection station 4 and unloading station are set on the placement platform 1. Multiple workstations surround the turntable 2 and cooperate with the nut placement holes 5 on the turntable 2. The nut loading station, bolt loading and pre-tightening station, and unloading station are all common technologies in this field. They can be implemented using vibratory feeders, gripper cylinders, ball screw modules, etc., and the pre-tightening function can be implemented using rotary cylinders. This equipment focuses on improving the design of tightening station 3 and inspection station 4, as follows: The main function of tightening station 3 is to tighten the bolts and nuts and apply a certain preload to ensure that the bolts and nuts will not loosen during transportation and to enable the bolts and nuts to be quickly separated during use. The main function of inspection station 4 is to perform vibration tests on the tightened bolts and nuts to detect any looseness.

[0033] Specifically, a lifting adjustment module 6 is set in the tightening station 3 and the testing station 4. A mounting frame 7 is set on the lifting adjustment module 6. A rotating bolt module 8 is installed on the mounting frame 7. The rotating bolt module 8 can drive the bolt to rotate. In tightening station 3, the rotating bolt module 8 can apply a certain preload force between the bolt and the nut.

[0034] In inspection station 4, the rotating bolt module 8 is only used to move the assembled bolts and nuts up and down.

[0035] Meanwhile, a vibration detection module 13 is set up in the detection station 4. The rotating bolt module 8 in the detection station 4 will transport the bolts and nuts to the vibration detection module 13, and the vibration detection module 13 will generate vibration to detect the looseness of the bolts and nuts.

[0036] By using multiple workstations in coordination, the entire process of nut loading, bolt pre-tightening, torque tightening, vibration detection, and finished product unloading can be completed automatically. This not only improves the efficiency of assembly and inspection, but also allows for the early screening of products with unqualified pre-tightening force through vibration. This ensures that the grounding combination bolts and nuts will not loosen or fall off during transportation, avoiding the loss of parts and the problem of secondary assembly by customers, and effectively improving the user experience of the product.

[0037] Meanwhile, the integrated multi-station turntable design makes the entire equipment structure more compact, occupies less space, and is suitable for production site needs of different sizes.

[0038] Based on the above, the bolt and nut assembly and tightening process is as follows: When bolt and nut assembly and tightening operations are required, the turntable 2 drives the pre-tightened bolts and nuts from the bolt loading and pre-tightening station to the tightening station 3. The lifting and adjusting module 6 drives the mounting frame 7 and the rotating bolt module 8 to descend, so that the rotating bolt module 8 covers the head of the pre-tightened bolt. The rotating bolt module 8 drives the bolt to rotate, assembling the bolt and nut. After assembly, the rotating bolt module 8 outputs the set torque, tightening the bolt into the corresponding nut and outputting a stable preset preload force. After the tightening operation is completed, the rotating bolt module 8 stops rotating, the lifting and adjusting module 6 drives the rotating bolt module 8 to rise and reset, and the turntable 2 rotates to send the tightened bolts and nuts into the inspection station 4. In the testing station 4, the rotating bolt module 8 descends and drives the assembled bolts and nuts to be sent into the vibration testing module 13; Vibration detection module 13 is activated to perform vibration detection on the assembled bolts and nuts; After the vibration ends, the rotating bolt module 8 drives the bolt and nut to exit the vibration detection module 13. The detection sensor determines whether the bolt and nut have become loose. Qualified products are output as the turntable 2 rotates into the unloading station, while unqualified products are sorted and removed separately, completing the entire assembly tightening and detection process.

[0039] It should be noted that the bolt heads mentioned in this article are all hexagonal heads of conventional hexagonal bolts, and the dimensional tolerances and geometric tolerances specified in the national standard GB / T5782 are adopted. The bolt head type, basic standard and basic parameters will not be repeated in the following description.

[0040] like Figures 4-6 As shown, the rotating bolt module 8 mainly consists of a rotating frame 806, a lifting frame 805, a first spring 809, and an external air pipe 808, etc., and its specific structure is as follows: A rotating frame 806 is rotatably installed on the top of the mounting frame 7. A lifting frame 805 is slidably installed inside the rotating frame 806, and the lifting frame 805 and the rotating frame 806 are only slidably connected. A bolt insertion hole 810 is provided at the bottom of the lifting frame 805, and bolts can be inserted into the bolt insertion hole 810. A turntable 807 is fixedly installed on the top of the lifting frame 805. A first spring 809 is provided between the lifting frame 805 and the rotating frame 806. The first spring 809 always pushes the lifting frame 805 to move downward, ensuring that the lifting frame 805 is always at the lowest point. An external air pipe 808 is installed on the top of the lifting frame 805. The external air pipe 808 is connected to an external negative pressure generating device (such as a rotary vane pump). The air inlet of the external air pipe 808 extends through the air passage 811 into the bolt insertion hole 810, and can fix the bolt head inserted into the bolt insertion hole 810 by negative pressure adsorption.

[0041] When it is necessary to tighten bolts and nuts, the lifting adjustment module 6 drives the lifting frame 805 and the rotating frame 806 to move downward synchronously, so that the lifting frame 805 contacts the bolt head. As the rotating frame 806 continues to descend, the bolt head is inserted into the bolt hole 810 and the first spring 809 is compressed. Subsequently, the rotating frame 806 drives the lifting frame 805 and the bolt to rotate synchronously. The lifting frame 805 will move downward under the action of the first spring 809, thereby completing the tightening operation of the bolt and nut.

[0042] After tightening, the lifting adjustment module 6 drives the entire structure to rise and reset, and the lifting frame 805 resets to the lowest point, preparing for the next operation.

[0043] By utilizing the elasticity and floating of the spring, pressure output can be maintained during the tightening process, ensuring that the bolt and the lifting frame 805 remain in contact during the tightening process.

[0044] like Figure 4 As shown, in order to drive the rotating frame 806 to rotate, a drive assembly is also provided. The drive assembly is set on the mounting frame 7 and mainly consists of a servo motor 802, a first gear 803 and a second gear 804. The specific structure is as follows.

[0045] A support frame 801 is fixedly installed on the top of the mounting bracket 7, and a servo motor 802 is fixedly installed on the top of the support frame 801. The first gear 803 is rotatably mounted on the top of the mounting bracket 7. The first gear 803 can be driven by the servo motor 802. A second gear 804 is fixedly installed on the outside of the rotating frame 806. The second gear 804 meshes with the first gear 803, so that when the servo motor 802 drives the first gear 803, it drives the second gear 804, thereby driving the rotating frame 806 and the lifting frame 805 to rotate as a whole, so as to realize the bolt tightening operation.

[0046] In addition, both the first gear 803 and the second gear 804 can be helical gears, which have high transmission accuracy, good stability, and can accurately control the rotational torque to ensure that the output of the preload meets the set requirements.

[0047] The servo motor 802 can also be used with an encoder to precisely control the output angle, and those skilled in the art can set it according to actual needs.

[0048] Furthermore, in the tightening station 3, the rotating bolt module 8 is also equipped with a first touch switch 10 and a torque sensor 9, as detailed below: The first touch switch 10 is fixedly installed above the mounting bracket 7 and is used in conjunction with the turntable 807 to control the start of the servo motor 802 when the turntable 807 is disengaged from the first touch switch 10. The torque sensor 9 (a strain gauge torque sensor can be selected, which can detect the tightening torque output by the servo motor 802 in real time, and can be purchased according to actual needs) is fixedly installed on one side of the support frame 801. The input end is fixed to the output shaft of the servo motor 802, and the output end is fixed to the first gear 803. The torque sensor 9 is used in conjunction with the first touch switch 10 to ensure that the torque of the assembly between all bolts and nuts is a constant value.

[0049] Specifically, when the bolt head has not yet contacted the nut, the lifting frame 805 is not at its lowest point due to the obstruction of the bolt head. Therefore, the turntable 807 is not in contact with the first touch switch 10. Driven by the servo motor 802, the lifting frame 805 will rotate the bolt, aligning the bolt hole 810 with the edge of the bolt head, thereby causing the lifting frame 805 to move downward. When the bolt head contacts the nut, the turntable 807 will contact the first touch switch 10 and trigger a signal. At this time, the torque sensor 9 starts to work. When the torque sensor 9 detects the predetermined torque, it will control the servo motor 802 to stop running, completing the tightening operation and accurately controlling the preload to avoid insufficient preload causing loosening during transportation.

[0050] Furthermore, in the inspection station 4, the rotating bolt module 8 is also equipped with a second touch switch 14. The second touch switch 14 is fixedly installed above the mounting bracket 7 and is used in conjunction with the turntable 807 to control the start and stop of the servo motor 802 in the inspection station 4.

[0051] That is, when the bolt head cannot be inserted into the bolt hole 810 at the bottom of the lifting frame 805 due to misalignment of the edges, the lifting frame 805 cannot fall to the lowest point. At this time, the servo motor 802 is started, and the servo motor 802 drives the rotating frame 806 to rotate, which in turn drives the lifting frame 805 to rotate, so that the bolt hole 810 is aligned with the bolt head. Under the action of the first spring 809, the bolt head is inserted into the bolt hole 810, and the connection between the lifting frame 805 and the bolt is completed. Then, the external negative pressure generating device is activated, and negative pressure is formed in the bolt insertion hole 810 through the external air pipe 808 and air channel 811, which firmly attracts and fixes the bolt head, completing the docking of the bolt nut with the rotating bolt module 8. After docking, the lifting adjustment module 6 drives the whole to descend, sending the bolt nut into the vibration detection module 13 to carry out the detection operation.

[0052] It should be noted that both the first contact switch 10 and the second contact switch 14 can be conventional limit switches available on the market. They are inexpensive, have stable triggering, and can meet the triggering requirements of the equipment's reciprocating operation. No special accessories need to be customized, which facilitates the later maintenance and replacement of parts of the equipment.

[0053] like Figure 3As shown, the lifting adjustment module 6 mainly consists of a fixed base 601, a linear module 602, and a slide 603, as detailed below: A fixed base 601 is fixedly installed on the placement platform 1. A linear module 602 (a ball screw module or a synchronous belt linear slide can be selected) is fixedly installed on one side of the fixed base 601. Those skilled in the art can select according to the actual load and accuracy requirements. A slide 603 is fixedly installed on the mover (slider) of the linear module 602. A mounting bracket 7 is fixedly installed on the slide 603. The linear module 602 drives the slide 603 and the mounting bracket 7 to move in the vertical direction, thereby realizing the lifting and lowering action of the entire rotating bolt module 8. The overall structure is simple, the transmission accuracy is high, and the lifting distance and speed can be stably controlled, which is suitable for the operation requirements of bolt and nut station conversion, fastening, inspection, etc.

[0054] like Figures 10-11 As shown, the vibration detection module 13 mainly consists of an electric push rod 1301, a detection frame 1305, a vibration motor 1306, a first distance sensor 11, and a second distance sensor 12, as detailed below: An electric push rod 1301 (a linear motion power actuator that converts electrical energy into mechanical energy, which can be connected to an external power supply and control switch and drive the push rod to perform linear reciprocating motion by controlling the forward and reverse rotation of the motor; it can be used in conjunction with a limit switch or Hall sensor to achieve safety protection and position control of the push rod's extension and retraction stroke; those skilled in the art can set it according to actual needs) is fixedly installed at the movable end of the electric push rod 1301. The guide frame 1302 is slidably installed with the fixed base 601, and a clearance groove 1303 is provided through the top of the guide frame 1302. A detection frame 1305 is set in the clearance groove 1303 and connected to the guide frame 1302 by a second spring 1304. The second spring 1304 can support the detection frame 1305 to always remain in the initial position, allowing the detection frame 1305 to float elastically in the clearance groove 1303. A vibration motor 1306 (an eccentric vibration motor can be selected, which can output vibrations of different frequencies and amplitudes, and the working power can be adjusted according to the requirements) is fixedly installed below the testing frame 1305. The top of the testing frame 1305 is provided with a placement groove 1309, which has the same shape as the nut placement hole 5. After the assembled bolt and nut are placed into the placement groove 1309, the nut is supported by the placement groove 1309. Sliding grooves 1310 are provided on both sides of the clearance groove 1303, so that the testing frame 1305 can move in the sliding groove 1310.

[0055] It should be noted that both the first spring 809 and the second spring 1304 are common wear parts, and their periodic replacement is within the scope of routine equipment maintenance. In actual use, the frequency of use and lifespan of the springs are within a reasonable range and will not affect the overall stability of the equipment.

[0056] Meanwhile, an electromagnetic lock 1307 (which can be an energized lock, with the locking pin extending when energized and retracting when de-energized, can be fixedly installed at the bottom of the guide frame 1302; the wiring method can be selected according to actual control requirements, and can be flexibly set by those skilled in the art) is provided on both sides of the bottom of the test frame 1305. The plug 1308 is used in conjunction with the electromagnetic lock 1307 to fix the position of the test frame 1305 and to make the test frame 1305 quickly stabilize.

[0057] When it is necessary to test the connection of bolts and nuts, the pin end of the electromagnetic lock 1307 is disengaged from the socket 1308. At this time, the vibration motor 1306 is started. The vibration motor 1306 will drive the test frame 1305 and the nut to vibrate at high frequency together to perform vibration test on the assembled bolts and nuts. The first distance sensor 11 is fixedly installed on one side of the mounting base 601, with the detection end facing the side of the bolt head placed in the placement slot 1309; The second distance sensor 12 is fixedly installed at the bottom of the mounting bracket 7, with the detection end facing the top of the bolt head placed in the placement slot 1309; The first distance sensor 11 and the second distance sensor 12 work together to detect the position change of the bolt head before and after vibration in both radial and axial directions. If the position change exceeds the preset threshold, it can be determined that the preload of the bolt and nut is unqualified and will be rejected by the subsequent sorting mechanism. After the vibration test is completed, the pin end of the electromagnetic lock 1307 extends out and inserts into the socket 1308 to quickly lock the floating test frame 1305, so as to avoid the residual vibration of the test frame 1305 from affecting the accuracy of the position detection and to ensure that the test results are accurate and reliable. In addition, an elastic rubber pad 1311 can be set at the pin end (locking pin) of the electromagnetic lock 1307 near the end of the test frame 1305. During the process of the electromagnetic lock 1307 locking the test frame 1305, the locking pin will extend towards the test frame 1305. If the locking pin is not aligned with the insertion port 1308, the elastic rubber pad 1311 will press against the side wall of the test frame 1305, causing the test frame 1305 to stop quickly. Under the action of the second spring 1304, the test frame 1305 will move slightly to adjust its position in the relief groove 1303. The locking pin will repeatedly extend and retract until the insertion port 1308 is aligned with the locking pin, and the locking pin will be successfully inserted to complete the locking, thus avoiding the failure of locking from affecting the progress of subsequent testing processes. Using electromagnetic lock 1307 to lock the detection frame 1305 is only one embodiment of the present invention. Other locking structures such as cylinder telescopic pins and electric locking pins can also be used instead. Those skilled in the art can flexibly choose according to actual control and cost requirements without affecting the normal realization of the detection function of this solution.

[0058] When the first distance sensor 11 and the second distance sensor 12 are used for detection, they will detect the position of the bolt head before and after vibration, and compare the two sets of data before and after detection. If the bolt and nut become loose, the bolt will move downward along the nut axis, and the bolt head will rotate. Since the bolt head is hexagonal, the data detected by the first distance sensor 11 and the second distance sensor 12 will have deviations. If the deviation value exceeds the set threshold, the product can be determined to be unqualified, and a sorting signal will be triggered to reject it.

[0059] It should be noted that both the first distance sensor 11 and the second distance sensor 12 can be laser rangefinders or ultrasonic rangefinders, as long as they can accurately detect the positional changes of the bolt head. Those skilled in the art can flexibly choose according to the detection accuracy requirements and the usage environment to ensure the accuracy of position detection.

[0060] The following is the specific operating principle of this device: After the turntable 2 rotates the station with bolts and nuts to the tightening station 3, the linear module 602 in the tightening station 3 drives the mounting frame 7 to move downward, so that the rotating frame 806 and the lifting frame 805 descend synchronously. As the mounting frame 7 continues to descend, because the bolt head is misaligned with the insertion hole of the lifting frame 805, after the bolt head contacts the lifting frame 805, the bolt head pushes the lifting frame 805 to move upward relative to the rotating frame 806, thereby causing the turntable 807 to disengage from the first touch switch 10. At this time, the disengagement of the turntable 807 at the top of the lifting frame 805 will trigger the first touch switch 10 to cut off the power. Subsequently, the servo motor 802 starts and drives the rotating frame 806 and the lifting frame 805 to rotate synchronously through the meshing of the first gear 803 and the second gear 804, so that the bolt head will be inserted into the bolt insertion hole 810 at the bottom of the lifting frame 805 and the bolt will be driven to rotate synchronously by the lifting frame 805. The bolt is tightened by the elastic pressure of the first spring 809. When the bolt head contacts the nut, the turntable 807 will contact the first touch switch 10. At this time, the first touch switch 10 is energized, triggering the torque sensor 9 to work. The servo motor 802 stops running and the tightening operation is completed when the torque sensor 9 detects that the tightening torque has reached the set value. Subsequently, the linear module 602 drives the entire rotary bolt module 8 to rise and reset, and the turntable 2 rotates to send the bolt and nut into the inspection station 4; The lifting adjustment module 6 of the inspection station 4 repeats the above-mentioned descent action. When the mounting frame 7 descends to the preset position, if the bolt head is not aligned and inserted into the bolt socket 810, the lifting frame 805 cannot fall to the lowest point, and the second touch switch 14 is not triggered. At this time, the servo motor 802 starts to drive the lifting frame 805 to rotate and adjust its position until the bolt head is successfully inserted and the docking adsorption is completed. At this time, the turntable 807 on the lifting frame 805 will contact the second touch switch 14 and trigger the second touch switch 14, thereby stopping the servo motor 802. Afterwards, the external negative pressure generating device operates, forming negative pressure in the bolt insertion hole 810, which firmly attaches the bolt to the lifting frame 805. Then, the lifting adjustment module 6 drives the bolt and nut to lift upward together, disengaging from the nut placement hole 5 on the turntable 2. Start the electric push rod 1301 to drive the guide frame 1302 to move, so that the placement slot 1309 is located below the bolt and nut, and then put the bolt and nut into the placement slot 1309 of the vibration detection module 13 as a whole; Subsequently, the negative pressure generating equipment stopped operating, and the bolt and nut were supported by the placement groove 1309. Then, the lifting and adjusting module 6 drove the rotating bolt module 8 to rise and reset, and the electric push rod 1301 drove the guide frame 1302 and the detection frame 1305 to reset. At this time, the first distance sensor 11 and the second distance sensor 12 respectively detect the initial position of the bolt head and record the initial data. Then, the electromagnetic lock 1307 unlocks the detection frame 1305, starts the vibration motor 1306, and drives the detection frame 1305 and the bolt and nut to vibrate for a set time (such as 5 seconds) to detect the loosening of the bolt and nut. After the vibration ends, the electromagnetic lock 1307 automatically extends the locking pin and inserts into the socket 1308 to lock the test frame 1305. The first distance sensor 11 and the second distance sensor 12 detect the position of the bolt head again and compare the detection data with the initial data. Based on whether the position deviation exceeds the threshold, it is determined whether the bolt and nut assembly is qualified. After the inspection is completed, the electric push rod 1301 drives the guide frame 1302 to move, and works with the lifting adjustment module 6 and the negative pressure generating equipment to unload the bolts and nuts, so that the inspected bolts and nuts can re-enter the turntable 2 and wait for the next set of bolts and nuts to enter the inspection process. Qualified products flow into the unloading station, and unqualified products are rejected (a robotic arm and gripper cylinder can be used to cooperate). Qualified products are directly output, completing the entire automatic tightening and inspection operation of bolts and nuts. This process is repeated to form a continuous, automated workflow.

[0061] Finally, the following points should be noted: In the description of this application, it should be noted that, unless otherwise specified and limited, the terms "installation", "connection" and "linkage" should be interpreted broadly, and can be mechanical or electrical connection, or internal connection between two components, or direct connection. "Up", "down", "left", "right", etc. are only used to indicate relative positional relationship. When the absolute position of the described object changes, the relative positional relationship may change. The electronic components and modules used in this invention can all be commonly used parts on the market that can achieve the specific functions in this case, and the specific models and sizes can be selected and adjusted according to actual needs; The accompanying drawings of the embodiments disclosed in this invention only involve structures relevant to the embodiments disclosed in this invention. Other structures can be referred to with common designs. Unless otherwise specified, the same embodiment and different embodiments of this invention can be combined with each other.

Claims

1. A grounding combination bolt and nut assembly tightening testing device, characterized in that, include: Placement platform (1), a turntable (2) is provided on the placement platform (1), and a nut placement hole (5) for placing nuts is provided on the disc of the turntable (2). Tightening station (3) is set on the placement platform (1) and is used to tighten bolts and nuts and apply torque; The inspection station (4) is set on the placement platform (1) and located behind the tightening station (3) for inspecting bolts and nuts that are screwed together; The lifting adjustment module (6) is set in the tightening station (3) and the testing station (4) and installed on the placement platform (1). The lifting adjustment module (6) is equipped with a mounting bracket (7). The rotating bolt module (8) is set in the tightening station (3) and the inspection station (4), and is installed on the mounting bracket (7) to drive the bolt to rotate; The vibration detection module (13) is set in the detection station (4) and is used to perform vibration detection on the installed bolts and nuts.

2. The grounding combination bolt and nut assembly tightening testing device according to claim 1, characterized in that: The rotating bolt module (8) includes: Rotary bracket (806) is rotatably mounted on top of mounting bracket (7); The lifting frame (805) is slidably installed inside the rotating frame (806) and is only slidably connected to the rotating frame (806). The bottom of the lifting frame (805) is provided with bolt holes (810) and the top is fixedly installed with a turntable (807). The first spring (809) is disposed between the lifting frame (805) and the rotating frame (806); An external air pipe (808) is installed on the top of the lifting frame (805) and connected to the bolt hole (810) through the air passage (811); A drive assembly, mounted on the mounting bracket (7), is used to drive the rotating bracket (806) to rotate.

3. The grounding combination bolt and nut assembly tightening testing device according to claim 2, characterized in that: The driving component includes: The support frame (801) is fixedly installed on the top of the mounting frame (7), and a servo motor (802) is fixedly installed on the top of the support frame (801). The first gear (803) is rotatably mounted on the top of the mounting bracket (7), connected to the output shaft of the servo motor (802), and driven by the servo motor (802); The second gear (804) is fixedly installed on the outside of the rotating frame (806) and meshes with the first gear (803).

4. The grounding combination bolt and nut assembly tightening testing device according to claim 3, characterized in that: The rotary bolt module (8) located in the tightening station (3) also includes: The first touch switch (10) is fixedly installed above the mounting bracket (7) and used in conjunction with the turntable (807); The torque sensor (9) is fixedly installed on one side of the support frame (801). Its input end is fixed to the output shaft of the servo motor (802), and its output end is fixed to the first gear (803). The torque sensor (9) is used in conjunction with the first touch switch (10).

5. The grounding combination bolt and nut assembly tightening testing device according to claim 3, characterized in that: The rotating bolt module (8) located in the inspection station (4) also includes: The second touch switch (14) is fixedly installed above the mounting bracket (7) and used in conjunction with the turntable (807) to control the start and stop of the servo motor (802) in the detection station (4).

6. The grounding combination bolt and nut assembly tightening testing device according to claim 1, characterized in that: The vibration detection module (13) includes: An electric push rod (1301) is installed on one side of the lifting adjustment module (6). A guide frame (1302) is fixedly installed on the movable end of the electric push rod (1301). A clearance groove (1303) is opened through the top of the guide frame (1302). The testing frame (1305) is set in the clearance groove (1303) and connected to the guide frame (1302) through the second spring (1304). The top of the testing frame (1305) is provided with a placement groove (1309), which has the same shape as the nut placement hole (5). A vibration motor (1306) is fixedly installed below the testing frame (1305) to drive the vibration of the testing frame (1305); The first distance sensor (11) is installed on one side of the lifting adjustment module (6), with the detection end facing the bolt placed in the placement slot (1309); The second distance sensor (12) is fixedly installed at the bottom of the mounting bracket (7), with the detection end facing the bolt placed in the placement slot (1309). The first distance sensor (11) and the second distance sensor (12) are used together.

7. The grounding combination bolt and nut assembly tightening testing device according to claim 6, characterized in that: The vibration detection module (13) also includes: The socket (1308) is located on both sides of the bottom of the testing frame (1305); The electromagnetic lock (1307) is fixedly installed at the bottom of the guide frame (1302) and is used in conjunction with the socket (1308).

8. The grounding combination bolt and nut assembly tightening test equipment according to claim 6, characterized in that: The lifting adjustment module (6) includes: The fixed base (601) is fixedly installed on the placement platform (1), the electric push rod (1301) is fixed on one side of the fixed base (601), and the guide frame (1302) is slidably installed with the fixed base (601); The linear module (602) is fixedly installed on one side of the fixed base (601). A slide (603) is fixedly installed on the mover of the linear module (602). The slide (603) is slidably installed with the fixed base (601), and the slide (603) is fixed with the mounting bracket (7).

9. The grounding combination bolt and nut assembly tightening test equipment according to claim 7, characterized in that: The clearance groove (1303) has sliding grooves (1310) on both sides, and the detection frame (1305) is installed in the sliding groove (1310).

10. A process for testing the tightening of grounding combination bolts and nuts, applicable to the grounding combination bolt and nut assembly tightening testing equipment as described in claim 1, characterized in that, Includes the following steps: Step 1: When bolt and nut assembly and tightening operations are required, the turntable (2) drives the pre-tightened bolt and nut from the bolt loading pre-tightening station to the tightening station (3). The lifting adjustment module (6) drives the mounting frame (7) and the rotating bolt module (8) to descend, so that the rotating bolt module (8) covers the head of the pre-tightened bolt. Step 2: The rotating bolt module (8) drives the bolt to rotate, assembling the bolt and nut. After assembly, the rotating bolt module (8) outputs the set torque to tighten the bolt into the corresponding nut and output a stable preset preload force. Step 3: After the tightening operation is completed, the rotating bolt module (8) stops rotating, the lifting adjustment module (6) drives the rotating bolt module (8) to rise and reset, and the turntable (2) rotates to send the tightened bolts and nuts into the inspection station (4). Step 4: In the testing station (4), the rotating bolt module (8) descends and drives the assembled bolts and nuts to be sent into the vibration testing module (13); Step 5: The vibration detection module (13) is started to perform vibration detection on the assembled bolts and nuts; Step 6: After the vibration ends, the rotating bolt module (8) drives the bolt and nut to exit the vibration detection module (13). The detection sensor determines whether the bolt and nut have become loose. Qualified products are output as the turntable (2) rotates into the unloading station. Unqualified products are sorted and removed separately, completing the entire assembly tightening detection process.

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