An apparatus for assembling a screw and a nut

Abstract

The application discloses a screw and nut assembling device, which comprises a rotating driving device, a screw clamping device, a nut positioning device, an axial force sensor and a control device. The inner wall of the clamping groove of the screw clamping device is provided with a rotating roller, which allows the screw to rotate freely around its own axis without damaging the surface of the screw while clamping the screw; the supporting groove is arranged on the supporting block of the nut positioning device, the limiting side walls on both sides limit the rotation of the nut, the top stop flange limits the axial displacement of the nut and serves as mechanical limiting for assembly in place; the axial force sensor first senses the pressure signal of the nut abutting against the screw to confirm the assembly in place, and then senses the tension signal of the nut abutting against the top stop flange and the supporting block being driven to rise, and the control device controls the rotating driving device to stop rotating when the tension reaches a predetermined value. The application has high reliability, the clamping position does not drift, the assembly in place is accurately determined and is not interfered by thread friction, rotating speed and incoming tolerance, and the consistent screwing degree is ensured in long-term use.

Description

Technical Field

[0001] This invention belongs to the field of injection molding nut pre-embedding process, specifically relating to an assembly device for screws and nuts. Background Technology

[0002] Pre-embedded injection molded nuts are a common process in plastic product manufacturing. In this process, a screw, as an auxiliary component, is pre-engaged and locked to the pre-embedded nut. The outer section of the screw is inserted into the positioning hole of the mold to precisely fix the nut in the center of the cavity. During injection molding, the screw prevents molten plastic from entering the nut's threads and wraps around the nut's outer wall. After the injection molding cools and the mold opens, the screw is unscrewed. Therefore, assembling and connecting the screw and nut is the first step in the pre-embedded injection molded nut process. The consistency of the assembly and the integrity of the screw surface directly determine the accuracy of subsequent injection molding positioning and the product yield.

[0003] In existing technology, the assembly of the screw and nut is usually accomplished by a rigid clamping jaw in conjunction with a rotary drive mechanism. The operation involves the rigid jaws gripping the outer wall of the screw, driving the screw to rotate, and then releasing the jaws once the screw and nut have engaged to a certain extent. However, the reliability of existing equipment significantly decreases after long-term use, specifically manifested in the following ways:

[0004] Firstly, the rigid clamping method creates a trade-off between clamping and rotation. For the screw to rotate while clamped, the rigid jaws must maintain a certain contact with the screw's outer wall, resulting in continuous sliding friction between the screw and the jaws during rotation. Over time, this sliding friction causes scratches and wear on the screw surface. As an auxiliary component in injection molding, surface damage directly affects the positioning accuracy of subsequent assembly. Furthermore, it causes wear on the clamping surfaces of the jaws, gradually reducing the clamping force. Ultimately, this leads to problems such as inaccurate screw clamping and upward displacement of the screw's clamping position (i.e., the effective clamped portion of the screw drifts axially).

[0005] Secondly, the degree of engagement between the screw and nut is usually determined based on the preset number of rotations of the servo motor. That is, the assembly is considered complete when the motor stops rotating after the preset number of rotations. Due to differences in thread friction, fluctuations in rotation speed, and dimensional tolerances of the incoming nut, the actual engagement depth corresponding to the same preset number of rotations already has a deviation. When the clamping position moves upward and the clamping force decreases, the effective length of the screw participating in the engagement changes accordingly, further amplifying the deviation in the actual engagement depth corresponding to the same preset number of rotations.

[0006] In summary, the two problems mentioned above overlap, leading to defects in existing equipment after long-term use, such as inconsistent screw-in degree, missing parts, over-screwing, or improper assembly. These defects become more severe with prolonged use, requiring frequent downtime for maintenance, and making it difficult to guarantee production efficiency and yield. Summary of the Invention

[0007] To address the aforementioned shortcomings of the prior art, the purpose of this application is to provide an assembly device for a screw and a nut, which simultaneously meets the following requirements during the automated engagement process of "rotating the screw to feed the nut": the clamping and transfer process does not result in the nut falling off and allows for rotational assembly without damaging the screw surface or the clamping structure; the nut is both anti-rotation and allows for axial climbing without coming off; the assembly position determination is reliable, and the engagement degree remains consistent after long-term use.

[0008] To achieve the above objectives, this application provides the following technical solution:

[0009] An assembly device for a screw and nut includes: a rotary drive device, a screw clamping device, a nut positioning device, an axial force sensor, and a control device. Wherein:

[0010] A rotary drive is used to drive a screw to rotate about its own axis.

[0011] The screw clamping device includes a clamping assembly, which has a clamping groove for clamping the screw. The inner wall of the clamping groove is provided with a rotating roller. The rotating roller is used to allow the screw to rotate freely about its own axis while clamping the screw, so that the screw and the nut to be assembled are coaxially opposite each other.

[0012] The nut positioning device includes a support block with a support groove for accommodating the nut. Limiting sidewalls are provided on opposite sides of the support groove, with the distance between the two limiting sidewalls matching the nut to restrict rotation of the nut around its own axis. A stop flange is provided at the top of the limiting sidewalls to restrict the nut's displacement along the screw axial direction, preventing the nut from dislodging from the support groove. The support block can move along the screw axial direction to drive the nut to coaxially abut against the screw, and allows the nut to climb along the screw thread as the screw rotates.

[0013] The axial force sensor is connected to the support block and is used to detect the axial tensile force generated when the nut climbs up and hits the stop flange;

[0014] The control device is connected to the axial force sensor and the rotary drive device respectively. When the axial tension detected by the axial force sensor reaches a predetermined value, the rotary drive device is controlled to stop rotating to determine that the screw and nut are assembled.

[0015] Furthermore, the rotary drive device includes a lifting module, a servo motor, and a transmission connector. The servo motor is mounted on the lifting module, and the transmission connector is connected to the output end of the servo motor for connecting with the head end of the screw to drive the screw to rotate around its own axis. The lifting module is used to drive the servo motor and the transmission connector to move along the screw axis so that the transmission connector can connect or disconnect from the head end of the screw.

[0016] Furthermore, the nut positioning device also includes a lifting cylinder, the drive end of which is connected to the support block, and an axial force sensor is disposed between the lifting cylinder and the support block.

[0017] Furthermore, the assembly equipment also includes a positioning base with a guide channel. A support block is placed on the positioning base, and the structure of the support groove is consistent with the structure of the guide channel to ensure the stability of the nut's posture during the conveying process.

[0018] Furthermore, the positioning base is provided with a guide cylinder and a first push cylinder. The driving direction of the guide cylinder is perpendicular to the guide channel. The guide cylinder is connected to a guide block, and the guide block is provided with a guide groove for accommodating the nut. The driving direction of the first push cylinder is consistent with the moving direction of the nut in the guide channel. The first push cylinder is connected to a first push block, which is used to push the nut in the guide groove into the guide channel.

[0019] Furthermore, the assembly equipment also includes a first feeding mechanism for conveying nuts. The first feeding mechanism includes a first feeding disc and a first feeding channel. The first feeding channel is driven by a linear vibrator and is correspondingly arranged with a guide trough to convey the nuts into the guide trough.

[0020] Furthermore, the screw clamping device also includes a receiving platform. The clamping assembly includes two clamping arms arranged opposite each other. The receiving platform is provided with a receiving groove. The two clamping arms are slidably assembled in the receiving groove. Each clamping arm is connected to a clamping drive cylinder. The two clamping arms cooperate to form a clamping seat. The clamping groove is provided in the clamping seat. The clamping drive cylinder is used to drive the two clamping arms to move towards each other to clamp the screw, and to drive the clamping seat to slide along the receiving groove to transfer the screw above the support block.

[0021] Furthermore, the assembly equipment also includes a second feeding mechanism for conveying the screw. The second feeding mechanism includes a second feeding disc and a tubular second feeding channel. The inlet end of the second feeding channel is higher than the outlet end. The receiving platform is located directly below the outlet end of the second feeding channel. The screw moves along the second feeding channel under the action of gravity via the second feeding disc and falls between the two clamping arms.

[0022] Furthermore, the assembly equipment also includes a splitting mechanism for converting the assembled screws from a single row to multiple rows. The splitting mechanism includes a third feeding channel and a splitting platform. The splitting platform is provided with multiple parallel arrangement channels. The splitting platform is equipped with a splitting cylinder and multiple second push cylinders. The driving direction of the splitting cylinder is perpendicular to the conveying direction of the arrangement channels. The splitting cylinder is connected to a splitting block, and the splitting block is provided with multiple splitting slots, the number of which corresponds to the number of arrangement channels. The multiple second push cylinders correspond to the multiple arrangement channels, and the driving direction of the second push cylinders is consistent with the conveying direction of the arrangement channels. The second push cylinders are connected to second push blocks.

[0023] Furthermore, the assembly equipment also includes a tray loading mechanism, which includes a transport module and an output module. The transport module has a two-axis movement function and is equipped with a transport mounting plate. The transport mounting plate is equipped with multiple grippers, and the multiple grippers correspond to the position and layout of the arrangement channels. The output module is a linear movement module, and a material tray is placed on the output module.

[0024] Compared with the prior art, this application has the following beneficial effects:

[0025] 1. High reliability and long-term precision maintenance: The screw clamping device has a rotating roller installed on the inner wall of the clamping groove. The screw makes rolling contact with the rotating roller during clamping, resulting in rolling friction rather than sliding friction. This prevents scratching the screw surface and wear on the clamping structure during rotation. The clamping surface remains intact over time, the clamping force is stable, and the screw's clamping position does not drift. This avoids the reliability problems of existing technologies, such as "rigid clamping causing mutual wear between the screw and the jaws, upward shift of the clamping position over time, and gradual inconsistency in the degree of engagement." The equipment maintains consistent assembly precision throughout its entire lifespan.

[0026] 2. Precise and reliable assembly positioning: This application achieves precise positioning of the nut by using a stop flange in conjunction with an axial force sensor. Specifically, the axial force sensor outputs two characteristic signals in two stages throughout the assembly process: In the first stage, the support block drives the nut to abut against the lower end of the screw. The sensor first senses the pressure signal generated by the nut abutting against the screw, thus confirming that the part is in place. In the second stage, after the nut climbs along the thread to abut the stop flange, the screw continues to rotate, causing the nut and support block to tend to rise axially. The sensor then senses the tension signal generated by the support block being driven upward. When the tension signal reaches a predetermined value, the assembly is determined to be complete.

[0027] Because the stop flange provides a definite axial mechanical limit, the nut will only generate the specified axial tension when it is screwed into the same position that it abuts against the stop flange. Therefore, when the tension reaches the predetermined value, the final axial position of the nut can be directly locked. That is, the degree of engagement of the nut is constant and precise, and does not change with thread friction, speed fluctuation, or material size tolerance. It is also not affected by the drift of the clamping position. Compared with the existing technology that judges the degree of engagement by the number of rotations, the judgment accuracy is significantly improved, and defects such as missing parts, over-tightening, and improper assembly can be effectively avoided.

[0028] 3. Balancing clamping and transfer with rotational assembly: The rotating rollers on the inner wall of the clamping groove reliably support the screw during clamping and transfer, preventing the screw from falling off, while allowing the screw to rotate freely around its own axis. There is no need to loosen the clamps during assembly, further eliminating the accuracy loss caused by switching clamping states.

[0029] 4. Anti-rotation, climbing and anti-disengagement: Through the limiting sidewalls on both sides of the support groove and the stop flange on the top, the nut is restricted from rotating around its own axis, and can climb along the thread axis when the screw rotates. After climbing to the position, it is blocked by the stop flange and will not disengage or over-rotate, ensuring the stability and safety of the screwing process.

[0030] 5. High degree of automation: Through the coordination of mechanisms such as material feeding, guiding conveying, clamping and transferring, sorting and tray loading, the assembly and tray loading of screws and nuts are automated and continuous, improving production efficiency and assembly consistency. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the overall structure of the assembly equipment described in this application.

[0032] Figure 2 yes Figure 1 A magnified view of a portion of point A in the middle.

[0033] Figure 3 This is a top view of the assembly equipment described in this application.

[0034] Figure 4 This is a schematic diagram of the assembly structure of the rotary drive device, the screw clamping device, and the positioning base.

[0035] Figure 5 This is a top view of the screw clamping device and the positioning base.

[0036] Figure 6 This is a partial structural diagram of the screw clamping device.

[0037] Figure 7 It is a partial structural cross-sectional view of the rotary drive device, screw clamping device and positioning base.

[0038] Figure 8 yes Figure 7 A magnified view of a section at point B in the middle.

[0039] The annotations in the figure are explained as follows:

[0040] 1. Rotary drive device; 11. Lifting module; 12. Servo motor; 121. Transmission joint;

[0041] 2. Screw clamping device; 21. Clamping assembly; 22. Receiving platform; 221. Receiving channel; 23. Clamping arm; 231. Rotating roller; 24. Clamping drive cylinder;

[0042] 3. Nut positioning device; 31. Support block; 311. Support groove; 312. Limiting sidewall; 313. Stop flange; 32. Lifting cylinder; 33. Axial force sensor;

[0043] 4. Positioning base; 41. Guide channel; 42. Material guide cylinder; 43. Material guide block; 431. Material guide trough; 44. First push cylinder; 45. First push block;

[0044] 5. First feeding mechanism; 51. First feeding tray; 52. First feeding channel;

[0045] 6. Second feeding mechanism; 61. Second feeding tray; 62. Second feeding channel;

[0046] 7. Separating mechanism; 71. Third feeding channel; 72. Separating platform; 721. Arranging channel; 73. Separating cylinder; 74. Separating block; 741. Separating trough; 75. Second pushing cylinder; 76. Second pushing block;

[0047] 8. Loading mechanism; 81. Handling module; 82. Handling mounting plate; 83. Gripper; 84. Output module; 85. Material tray;

[0048] 9. Screw; 91. Nut. Detailed Implementation

[0049] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0050] In the following embodiments, the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0051] In the description of this invention, it should be understood that terms such as center, longitudinal, transverse, length, width, thickness, upper, lower, front, rear, left, right, vertical, horizontal, top, bottom, inner, outer, clockwise, counterclockwise, etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing and simplifying the description of this invention; therefore, they should not be construed as limiting this invention. Furthermore, terms such as first, second, etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features shown. In the description of this invention, unless otherwise expressly specified and limited, terms such as installation, connection, linking, etc., should be interpreted broadly, and those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0052] This application provides a screw and nut assembly device, which is applied to the automated screwing assembly and tray loading of screw 9 and pre-embedded nut 91 in the injection molding nut pre-embedding process.

[0053] like Figures 1 to 8As shown, the assembly equipment generally includes a first feeding mechanism 5, a second feeding mechanism 6, an assembly mechanism, a splitting mechanism 7, and a tray loading mechanism 8. The first feeding mechanism 5 is used to transport nuts 91, the second feeding mechanism 6 is used to transport screws 9, the assembly mechanism is used to assemble and connect screws 9 and nuts 91, the splitting mechanism 7 is used to convert the assembled screws 9 from a single row to multiple rows, and the tray loading mechanism 8 is used to transport multiple rows of screws 9 and load them into the tray 85. The structure and cooperation relationship of each mechanism are described below.

[0054] The first feeding mechanism 5 includes a first feeding plate 51 and a first feeding channel 52. The first feeding channel 52 is driven by a linear vibrator. Nuts 91 in the first feeding plate 51 are fed forward one by one along the first feeding channel 52 by vibration excitation generated by the linear vibrator, so that the nuts 91 are output one by one in a predetermined posture.

[0055] A positioning base 4 is provided on the discharge side of the first feeding channel 52. The positioning base 4 has a guide channel 41 extending along the conveying direction of the nut 91 to guide the nut 91 to move in a predetermined posture. The positioning base 4 also has a guide cylinder 42 and a first pushing cylinder 44. The driving direction of the guide cylinder 42 is perpendicular to the guide channel 41. The guide cylinder 42 is connected to a guide block 43, which has a guide groove 431 for accommodating a single nut 91. The first feeding channel 52 and the guide groove 431 are correspondingly arranged, and the nut 91 is conveyed from the first feeding channel 52 into the guide groove 431. The guide cylinder 42 drives the guide block 43 to move, aligning the guide groove 431 with the guide channel 41, thereby isolating the single nut 91 from the first feeding channel 52 and transferring it to the entrance of the guide channel 41.

[0056] The driving direction of the first pushing cylinder 44 is consistent with the moving direction of the nut 91 in the guide channel 41. The first pushing cylinder 44 is connected to the first pushing block 45. When the guide groove 431 is aligned with the guide channel 41, the first pushing cylinder 44 drives the first pushing block 45 to extend, pushing the nut 91 in the guide groove 431 into the guide channel 41. With the reciprocating pushing of the first pushing cylinder 44, the nut 91 moves forward along the guide channel 41 in sequence.

[0057] The assembly mechanism includes a rotary drive device 1, a screw clamping device 2, and a nut positioning device 3. The rotary drive device 1 includes a lifting module 11, a servo motor 12, and a transmission connector 121. The servo motor 12 is mounted on the lifting module 11, and the output end of the servo motor 12 is connected to the transmission connector 121. The lifting module 11 drives the servo motor 12 and the transmission connector 121 to move up and down along the axial direction of the screw 9, so that the transmission connector 121 is connected to or disconnected from the head end of the screw 9; the servo motor 12 drives the transmission connector 121 to rotate, thereby driving the screw 9 to rotate around its own axis.

[0058] The screw clamping device 2 includes a receiving platform 22 and a clamping assembly 21. The clamping assembly 21 includes two opposing clamping arms 23 and a clamping drive cylinder 24. The receiving platform 22 has a receiving channel 221, and the two clamping arms 23 are slidably assembled in the receiving channel 221. Each clamping arm 23 is connected to a clamping drive cylinder 24. The two clamping arms 23 cooperate to form a clamping seat, which has a clamping groove for clamping the screw 9. The inner wall of the clamping groove is provided with a rotating roller 231. The clamping drive cylinder 24 drives the two clamping arms 23 to move towards each other to clamp or release the screw 9 in the clamping groove; on the other hand, it drives the two clamping arms 23 and the clamping seat to slide along the receiving channel 221 to transfer the clamped screw 9 above the nut positioning device 3.

[0059] The rotating roller 231 is designed so that when the clamping groove holds the screw 9, the outer circumferential surface of the screw 9 is in rolling contact with the rotating roller 231. The screw 9 can rotate freely around its own axis while being clamped without falling out of the clamping groove. Because the clamping and rotation are in rolling contact, the surface of the screw 9 and the clamping structure will not wear due to repeated operation, and the clamping force and clamping position remain stable during long-term use.

[0060] The nut positioning device 3 includes a support block 31 and a lifting cylinder 32. The support block 31 has a support groove 311 for accommodating the nut 91. Limiting sidewalls 312 are provided on opposite sides of the support groove 311, the distance between which is adapted to the external dimensions of the nut 91, thereby restricting the nut 91 from rotating around its own axis while allowing the nut 91 to move along the extension direction of the support groove 311 (i.e., the axial direction of the screw 9). A stop flange 313 is provided at the top of the limiting sidewalls 312 to prevent the nut 91 from continuing to rise after it has climbed to its position along the thread, preventing the nut 91 from dislodging from the support groove 311 or over-twisting, and providing a definite axial mechanical limit for assembly positioning detection. The drive end of the lifting cylinder 32 is connected to the support block 31 and is used to drive the support block 31 to move up and down along the axial direction of the screw 9. An axial force sensor 33 is provided between the lifting cylinder 32 and the support block 31 to detect the axial force acting on the support block 31.

[0061] Furthermore, the support block 31 is disposed on the positioning base 4, and the structure of the support groove 311 is consistent with the structure of the guide channel 41 on the positioning base 4. In this way, when the nut 91 is conveyed along the guide channel 41 to the position of the support groove 311, its conveying posture is consistent with its assembly posture, thereby ensuring the stability of the nut 91's posture during the conveying and assembly process.

[0062] The second feeding mechanism 6 includes a second feeding disc 61 and a tubular second feeding channel 62. The inlet end of the second feeding channel 62 is higher than the outlet end. The receiving platform 22 is located directly below the outlet end of the second feeding channel 62. The screw 9 moves along the second feeding channel 62 under the action of gravity via the second feeding disc 61 and falls from the outlet end, landing precisely between the two clamping arms 23 on the receiving platform 22, that is, into the clamping groove of the clamping seat.

[0063] The assembly of the screw 9 and nut 91 is carried out according to the following procedure:

[0064] Feeding stage: Nut 91 is conveyed to guide groove 431 by first feeding mechanism 5. Guide cylinder 42 drives guide block 43 to align guide groove 431 with guide channel 41. First push cylinder 44 drives first push block 45 to push nut 91 into guide channel 41. With the reciprocating push of first push cylinder 44, nut 91 moves along guide channel 41 and enters support groove 311 of support block 31. At the same time, two clamping arms 23 move to directly below the feed end of second feeding channel 62. Screw 9 falls from second feeding channel 62 into clamping groove between two clamping arms 23. Clamping drive cylinder 24 drives two clamping arms 23 to move towards each other to clamp screw 9. Subsequently, one clamping drive cylinder 24 extends and the other clamping drive cylinder 24 retracts, so that clamping seat slides along receiving channel 221 to directly above support block 31, that is, screw 9 and nut 91 in support groove 311 are coaxially opposite each other.

[0065] Assembly Stage: The lifting cylinder 32 drives the support block 31 to rise, causing the nut 91 to contact the lower end of the screw 9. At this time, the axial force sensor 33 receives a pressure signal indicating that the part is in place. The lifting module 11 drives the servo motor 12 to descend, connecting the transmission joint 121 to the head end of the screw 9. The servo motor 12 drives the transmission joint 121 and the screw 9 to rotate around their own axis. Since the height of the screw 9 remains unchanged and the nut 91 is restricted from rotation by the limiting sidewall 312, the nut 91 climbs along the thread axis of the screw 9 during its rotation. When the nut 91 climbs and abuts the stop flange 313, the continued rotation of the screw 9 will cause the nut 91 and the support block 31 to move upward. The axial force sensor 33 detects the axial tension that causes the support block 31 to rise. When the axial tension reaches a predetermined value, the control device controls the servo motor 12 to stop rotating and determines that the screw 9 and the nut 91 are assembled. Subsequently, the lifting module 11 drives the servo motor 12 and the transmission joint 121 to rise, causing the transmission joint 121 to disengage from the head end of the screw 9; the two clamping arms 23 release their grip on the screw 9, and the screw 9 and the nut 91 assembled together fall down, disengaging from the contact with the stop flange 313.

[0066] The axial force sensor 33's signal is divided into two stages throughout the assembly process: the first stage is the pressure signal generated when the nut 91 abuts against the lower end of the screw 9, used to confirm the part's position; the second stage is the tension signal generated when the nut 91 abuts against the stop flange 313 and the support block 31 is driven upward, used to determine assembly completion. Since the stop flange 313 is a deterministic axial mechanical limiter, the nut 91 will only generate the specified tension when it is screwed into the same axial position as the stop flange 313. Therefore, using the tension reaching the predetermined value as the criterion for determining assembly completion can accurately lock the final screwing position of the nut 91. This criterion is independent of thread friction, the speed fluctuation of the servo motor 12, the dimensional tolerance of the nut 91, and whether the clamping position drifts. The degree of screwing remains consistent after long-term use, and the judgment result is accurate and reliable.

[0067] The sorting mechanism 7 is used to convert the assembled screws 9 from a single row to multiple rows for tray loading. The sorting mechanism 7 includes a third feeding channel 71 and a sorting platform 72. The sorting platform 72 has multiple parallel arrangement channels 721, the number of which depends on the tray loading requirements. The sorting platform 72 is equipped with a sorting cylinder 73 and multiple second push cylinders 75. The driving direction of the sorting cylinder 73 is perpendicular to the conveying direction of the arrangement channels 721. The sorting cylinder 73 is connected to a sorting block 74, which has multiple sorting slots 741, the number of which corresponds to the number of arrangement channels 721. Each of the multiple second push cylinders 75 corresponds one-to-one with one of the arrangement channels 721. The driving direction of the second push cylinder 75 is consistent with the conveying direction of the arrangement channels 721, and each second push cylinder 75 is connected to a second push block 76.

[0068] The assembled screws 9 are continuously fed forward along the guide channel 41 by the nut 91, moving towards the sorting mechanism 7, entering the third feeding channel 71, and then entering the sorting slots 741 of the sorting block 74 one by one from the third feeding channel 71. The sorting cylinder 73 drives the sorting block 74 to move, so that each sorting slot 741 is aligned with each arrangement channel 721; then each second push cylinder 75 drives the corresponding second push block 76 to push the screws 9 in each sorting slot 741 into the corresponding arrangement channel 721, thereby realizing the arrangement of single-row screws 9 into multiple-row screws 9.

[0069] The tray loading mechanism 8 includes a transport module 81 and an output module 84. The transport module 81 has two-axis movement capability and is equipped with a transport mounting plate 82. The transport mounting plate 82 is equipped with multiple grippers 83, the positions and layout of which correspond to the multiple rows of channels 721 on the sorting table 72. The output module 84 is a linear movement module, and a tray 85 is placed on the output module 84.

[0070] Once each slot 721 contains a screw 9, the transport module 81 drives the transport mounting plate 82 to move, causing each gripper 83 to simultaneously align with each slot 721 and grip the screw 9. The transport module 81 then transports the grippers 83 along with the screw 9 to the tray 85 on the output module 84, where the grippers 83 simultaneously release, loading the screw 9 into the tray 85. The output module 84 then drives the tray 85 to move linearly to receive and output the tray 85 filled with screws 9.

[0071] The scope of protection of this invention includes, but is not limited to, the above embodiments. The scope of protection of this invention is defined by the claims. Any substitutions, modifications, or improvements to this technology that are easily conceived by those skilled in the art fall within the scope of protection of this invention.

Claims

1. An assembly device for a screw and a nut, characterized in that, include: A rotary drive device (1) is used to drive the screw (9) to rotate around its own axis; The screw clamping device (2) includes a clamping assembly (21), which is provided with a clamping groove for clamping a screw (9). The inner wall of the clamping groove is provided with a rotating roller (231). The rotating roller (231) is used to allow the screw (9) to rotate freely around its own axis while clamping the screw (9), so that the screw (9) and the nut (91) to be assembled are coaxially opposite each other. The nut positioning device (3) includes a support block (31), which has a support groove (311) for accommodating the nut (91). The support groove (311) has limiting sidewalls (312) on opposite sides. The distance between the limiting sidewalls (312) on both sides is adapted to the nut (91) to restrict the nut (91) from rotating around its own axis. The top of the limiting sidewall (312) has a stop flange (313) for restricting the displacement of the nut (91) along the axial direction of the screw (9) to prevent the nut (91) from falling out of the support groove (311). The support block (31) can move along the axial direction of the screw (9) to drive the nut (91) to coaxially abut against the screw (9) and allow the nut (91) to climb along the thread of the screw (9) when the screw (9) rotates. An axial force sensor (33), connected to the support block (31), is used to detect the axial tension generated when the nut (91) climbs up and abuts against the stop flange (313); The control device is connected to the axial force sensor (33) and the rotary drive device (1) respectively, and is used to control the rotary drive device (1) to stop rotating when the axial tension detected by the axial force sensor (33) reaches a predetermined value, so as to determine that the screw (9) and the nut (91) are assembled.

2. The assembly equipment for screws and nuts according to claim 1, characterized in that, The rotary drive device (1) includes a lifting module (11), a servo motor (12), and a transmission connector (121). The servo motor (12) is mounted on the lifting module (11), and the transmission connector (121) is connected to the output end of the servo motor (12) for connecting with the head end of the screw (9) to drive the screw (9) to rotate around its own axis. The lifting module (11) is used to drive the servo motor (12) and the transmission connector (121) to move along the axial direction of the screw (9) so that the transmission connector (121) can connect or disconnect from the head end of the screw (9).

3. The assembly equipment for screws and nuts according to claim 1, characterized in that, The nut positioning device (3) also includes a lifting cylinder (32), the driving end of the lifting cylinder (32) is connected to the support block (31), and the axial force sensor (33) is disposed between the lifting cylinder (32) and the support block (31).

4. The assembly equipment for screws and nuts according to claim 1, characterized in that, It also includes a positioning base (4), on which a guide channel (41) is provided. The support block (31) is set on the positioning base (4). The structure of the support groove (311) is consistent with the structure of the guide channel (41) to ensure the stability of the nut (91) during the conveying process.

5. The assembly equipment for screws and nuts according to claim 4, characterized in that, The positioning base (4) is provided with a guide cylinder (42) and a first push cylinder (44). The driving direction of the guide cylinder (42) is perpendicular to the guide channel (41). The guide cylinder (42) is connected to a guide block (43). The guide block (43) is provided with a guide groove (431) for accommodating nuts (91). The driving direction of the first push cylinder (44) is consistent with the moving direction of the nuts (91) in the guide channel (41). The first push cylinder (44) is connected to a first push block (45). The first push block (45) is used to push the nuts (91) in the guide groove (431) into the guide channel (41).

6. The assembly equipment for screws and nuts according to claim 5, characterized in that, It also includes a first feeding mechanism (5) for conveying nuts (91), the first feeding mechanism (5) includes a first feeding plate (51) and a first feeding channel (52), the first feeding channel (52) is driven by a linear vibrator, the first feeding channel (52) is correspondingly arranged with the guide groove (431) for conveying nuts (91) into the guide groove (431).

7. The assembly equipment for screws and nuts according to claim 1, characterized in that, The screw clamping device (2) further includes a receiving platform (22). The clamping assembly (21) includes two clamping arms (23) arranged opposite to each other. The receiving platform (22) is provided with a receiving channel (221). The two clamping arms (23) are slidably assembled in the receiving channel (221). Each clamping arm (23) is connected to a clamping drive cylinder (24). The two clamping arms (23) cooperate to form a clamping seat. The clamping groove is provided in the clamping seat. The clamping drive cylinder (24) is used to drive the two clamping arms (23) to move towards each other to clamp the screw (9) and to drive the clamping seat to slide along the receiving channel (221) to transfer the screw (9) above the support block (31).

8. The assembly equipment for screws and nuts according to claim 7, characterized in that, It also includes a second feeding mechanism (6) for conveying the screw (9), the second feeding mechanism (6) includes a second feeding disc (61) and a tubular second feeding channel (62), the inlet end of the second feeding channel (62) is higher than the outlet end, the receiving platform (22) is located directly below the outlet end of the second feeding channel (62), the screw (9) moves along the second feeding channel (62) under the action of gravity via the second feeding disc (61) and falls between the two clamping arms (23).

9. The assembly equipment for screws and nuts according to claim 1, characterized in that, It also includes a sorting mechanism (7) for converting the assembled screws (9) from a single row to multiple rows. The sorting mechanism (7) includes a third feeding channel (71) and a sorting platform (72). The sorting platform (72) is provided with multiple parallel arrangement channels (721). The sorting platform (72) is equipped with a sorting cylinder (73) and multiple second push cylinders (75). The driving direction of the sorting cylinder (73) is perpendicular to the conveying direction of the arrangement channels (721). (73) Connected to a split block (74), the split block (74) is provided with a plurality of split slots (741), the plurality of split slots (741) correspond to the number of the plurality of arrangement channels (721); a plurality of second push cylinders (75) correspond to the plurality of arrangement channels (721), the driving direction of the second push cylinders (75) is consistent with the conveying direction of the arrangement channels (721), and the second push cylinders (75) are connected to a second push block (76).

10. The assembly equipment for screws and nuts according to claim 9, characterized in that, It also includes a tray loading mechanism (8), which includes a transport module (81) and an output module (84). The transport module (81) has a two-axis movement function. The transport module (81) is equipped with a transport mounting plate (82). The transport mounting plate (82) is equipped with multiple grippers (83). The multiple grippers (83) correspond to the position and layout of the arrangement channel (721). The output module (84) is a linear movement module. The output module (84) has a material tray (85) placed on it.

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