Robotic Automatic Bolt Tightening and Removal Method and System

Abstract

This invention discloses a method and system for automatically removing nails from a robot-controlled bolt tightening machine. The method includes the following steps: optimizing the nail-removing trajectory of the robot tightening gun, including the nail-removing position and posture of the nail-removing sleeve; cleaning the surface of the nail-removing sleeve; and installing a nail-removing guide device (wider at the top and narrower at the bottom) at the nail-feeding position of the nail-feeding station, so that the rotating, centrifugal nail-removing sleeve accurately enters the nail-feeding position through the guide device to remove the nail. This invention solves the problem of production line congestion and downtime caused by nail removal failures, improves the stability of automatic nail removal by the robot, and significantly increases production cycle time and capacity.

Description

Technical Field

[0001] This invention relates to the field of robotic automatic tightening in the automotive industry, specifically to a method and system for robotic automatic tightening and bolt removal. Background Technology

[0002] In the process of using robots to automatically tighten bolts on automotive assembly lines, the problem of NOK (No Knockout) during bolt removal has become increasingly prominent as production volume increases, with downtime due to failed bolt removal rising every week. Unlike other production lines, the finishing line is the last line in the workshop with no buffer zone; any downtime there poses a significant threat to production volume, greatly impacting production efficiency and resulting in serious economic losses. Summary of the Invention

[0003] The purpose of this invention is to provide a method and system for automatically tightening and removing bolts by a robot. By increasing non-production maintenance time and rationally setting the relevant steps and devices for the robot to remove bolts, the problem of failure in automatically grasping bolts by the robot is effectively solved, the stability of the robot to remove bolts is improved, and the downtime rate is reduced.

[0004] To achieve the above objectives, the robot automatic bolt tightening and nail removal method of the present invention includes the following steps: optimizing the nail removal trajectory of the robot tightening gun, including the nail removal position and nail removal posture of the nail removal sleeve of the robot tightening gun; cleaning the surface of the nail removal sleeve of the robot tightening gun; and setting a nail removal guide device that is wider at the top and narrower at the bottom at the nail feeding position of the nail feeding station device, so that the nail removal sleeve, which is in a rotating centrifugal state, can accurately enter the nail feeding position through the nail removal guide device to remove the nail.

[0005] In one embodiment of the above-mentioned robot automatic bolt tightening and nail removal method, the step of optimizing the nail removal trajectory of the robot tightening gun further includes the following steps: using a centering auxiliary column to extend the threaded part axis of the nail feeding position of the nail feeding station device, and adjusting the point trajectory of the robot tightening gun multiple times so that the nail removal sleeve is accurately moved to directly above the nail feeding position, and the sleeve axis of the nail removal sleeve coincides with the threaded part axis.

[0006] When the robot tightening gun removes nails, there are four rotation angles for the nail removal sleeve: 90 degrees, 180 degrees, 270 degrees, 360 degrees, and a maximum of 630 degrees. Since the bolt is slightly biased in a certain direction, the nail is removed by first reversing the rotation and then rotating it forward.

[0007] In one embodiment of the above-mentioned automatic bolt tightening and nail removal method for robots, the following steps are also included: periodically inspecting and replacing the bolt top pin of the nail feeding station device, and adding a spring component to the nail removal sleeve of the robot tightening gun.

[0008] In one embodiment of the above-mentioned robot automatic bolt tightening and nail removal method, the following steps are also included: removing irregular nails and periodically testing the magnetic force of the nail removal sleeve, and setting the magnetic force of the nail removal sleeve to be no less than a predetermined value.

[0009] The robotic automatic bolt tightening and nail removal system of the present invention includes a robotic tightening gun and a nail feeding station device. The robotic tightening gun includes a nail-removing sleeve, and the nail feeding station device includes a nail feeding platform. The feeding platform has a nail feeding position, and the nail feeding position has a threaded component axis. The system also includes a centering auxiliary column, which is movably disposed above the nail feeding platform. The centering auxiliary column includes a centering axis, and when the centering auxiliary column is disposed above the nail feeding platform, the centering axis coincides with the threaded component axis.

[0010] In one embodiment of the above-mentioned robotic automatic bolt tightening and nail removal system, the centering auxiliary column includes a first centering column and a second centering column, and the first centering column and the second centering column are connected by an adjusting screw.

[0011] In one embodiment of the above-mentioned robotic automatic bolt tightening and nail removal system, a sleeve cleaning device is also included, which includes a rotating head, a drive unit for driving the rotating head to rotate, and a brush head connected to the rotating head.

[0012] In one embodiment of the above-mentioned robot automatic bolt tightening and nail removal system, a nail removal guide device is further included. The nail removal guide device includes a guide funnel disposed at the nail feeding position. The top diameter of the guide funnel is larger than the bottom diameter of the guide funnel, and the bottom diameter of the guide funnel is adapted to the outer diameter of the nail removal sleeve.

[0013] In one embodiment of the above-described robotic automatic bolt tightening and nail removal system, the nail removal guide device further includes a support assembly, and the guide funnel is connected to the nail feeding position through the support assembly.

[0014] In one embodiment of the above-described robotic automatic bolt tightening and nail removal system, the robotic tightening gun further includes a spring component, and the nail removal sleeve includes a connecting outer cylinder and a rotating inner cylinder rotatably connected to the connecting outer cylinder, with the spring component abutting between the connecting outer cylinder and the rotating inner cylinder.

[0015] The beneficial effects of this invention are that the robot's automatic bolt tightening and nail removal method and system solve the problem of production line congestion and downtime caused by nail removal failure, greatly improve production cycle and capacity, and enhance the stability of robot automatic nail removal.

[0016] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments, but this is not intended to limit the present invention. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of an embodiment of the robotic automatic bolt tightening and nail removal system of the present invention;

[0018] Screw structure diagram;

[0019] Figure 2 This is a schematic diagram of the centering auxiliary column of an embodiment of the robot automatic bolt tightening and nail removal system of the present invention;

[0020] Figure 3 This is a schematic diagram of the sleeve cleaning device of the robot automatic bolt tightening and nail removal system of the present invention;

[0021] Figure 4 for Figure 3 A magnified view of a portion of the image;

[0022] Figure 5 This is a schematic diagram of the working operation of the nail-removing guide device of the robot automatic bolt tightening and nail-removing system of the present invention;

[0023] Figure 6 This is a top view schematic diagram of the guide funnel of the robot automatic bolt tightening and nail removal system of the present invention;

[0024] Figure 7 A schematic diagram showing the addition of a spring component to the robotic tightening gun of the robotic automatic bolt tightening and nail removal system of the present invention;

[0025] Figure 8 This is a schematic diagram showing the position of the bolt top pin in the robot automatic bolt tightening and removal system of the present invention;

[0026] Figure 9 and Figure 10 This is a step diagram of the robot's automatic bolt tightening and nail removal method of the present invention.

[0027] Among them, the attached figures are labeled

[0028] 100: Robotic Tightening Gun

[0029] 110: Nail Removal Sleeve

[0030] 200: Nail delivery station device

[0031] 210: Nail delivery station

[0032] 220: Bolt pin

[0033] 300: Centering auxiliary column

[0034] 310: First pair of central pillars

[0035] 320: Second pair of central pillars

[0036] 330: Adjusting screw

[0037] 340: Guide post

[0038] 400: Sleeve Cleaning Device

[0039] 410: Rotating head

[0040] 420: Drive Unit

[0041] 430: Brush head

[0042] 500: Nail Removal Guide Device

[0043] 510: Guide Funnel

[0044] 520: Bracket Assembly

[0045] E: Nail feeding position

[0046] S1: Axis of threaded component

[0047] S2: Centerline

[0048] S3: Sleeve axis

[0049] D1: Top diameter

[0050] D2: Bottom diameter Detailed Implementation

[0051] The technical solution of the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments to further understand the purpose, solution and effect of the present invention, but it is not intended to limit the scope of protection of the appended claims.

[0052] References to "an embodiment," "embodiment," "example embodiment," etc., in this specification refer to the fact that the described embodiment may include specific features, structures, or characteristics, but not every embodiment must include these specific features, structures, or characteristics. Furthermore, such statements do not refer to the same embodiment. Moreover, when describing specific features, structures, or characteristics in connection with embodiments, whether or not explicitly described, it is indicated that incorporating such features, structures, or characteristics into other embodiments is within the knowledge of those skilled in the art.

[0053] The specification and subsequent claims use certain terms to refer to specific components or parts. Those skilled in the art will understand that users or manufacturers may use different names or terms to refer to the same component or part. This specification and subsequent claims do not distinguish components or parts by differences in name, but rather by differences in function. The terms "comprising" and "including" used throughout the specification and subsequent claims are open-ended and should be interpreted as "including but not limited to". Furthermore, the term "connection" here includes any direct and indirect electrical connection means. Indirect electrical connection means include connections made through other means.

[0054] Furthermore, in the description of this invention, the terms "lateral", "longitudinal", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0055] like Figure 1 and Figure 2 As shown, the robotic automatic bolt tightening and nail removal system of the present invention includes a robotic tightening gun 100 and a nail feeding station device 200. The robotic tightening gun 100 picks up the threaded part on the nail feeding station device 200 and tightens it to a predetermined position on the product. The robotic tightening gun 100 includes a nail-picking sleeve 110, and the nail feeding station device 200 includes a nail feeding platform 210. The feeding platform 210 has a nail feeding position E, and the nail feeding position E has a threaded part axis S1, which is the axis of the threaded part to be picked up at the nail feeding position E. The robotic automatic bolt tightening and nail removal system of the present invention also includes a centering auxiliary column 300, which is movably disposed above the nail feeding platform 210. The centering auxiliary column 300 includes a centering axis S2. When the centering auxiliary column 300 is disposed above the nail feeding platform 210, the centering axis S2 coincides with the threaded part axis S1. By setting a centering auxiliary column 300, the present invention can extend the axis S1 of the threaded part, which is beneficial to the position and posture adjustment of the robot tightening gun 100 and improves the accuracy of nail picking.

[0056] When the robot tightening gun 100 is being positioned and adjusted, the sleeve axis S3 of the nail-removing sleeve 110 needs to be aligned with the centering axis S2 and the threaded component axis S1. At this time, the top protruding part of the centering auxiliary column 300 is positioned to correspond to the centering auxiliary bolt 10 adsorbed by the nail-removing sleeve 110 of the robot tightening gun 100, which greatly reduces the alignment distance between the nail-removing sleeve 110 and the nail feeding position E, and enables the robot tightening gun 100 to quickly achieve trajectory positioning.

[0057] The controller optimizes the nail-picking trajectory of the robot tightening gun 100. An extended centering auxiliary column 300 better aligns the nail-picking sleeve 110 with the bolt's centerline. The robot repeatedly adjusts the nail-picking point trajectory, and the controller records and calculates the center point and wobble between the nail-picking sleeve 110 and the bolt / nut at the nail-feeding position E, ultimately accurately determining the position. This invention significantly reduces the number of nail-picking failures due to point errors, improving nail-picking stability.

[0058] The centering auxiliary column 300 is, for example, a cylinder with a notch at its bottom. It is placed at the nail-feeding position E of the top-feeding platform 210, and the centering axis S2 of the centering auxiliary column 300 is adjusted to coincide with the threaded component axis S1. In other embodiments, an auxiliary bracket can be used to clamp the centering auxiliary column 300 between the centering auxiliary bolt 10 and the nail-feeding position E, and the centering axis S2 of the centering auxiliary column 300 is set to coincide with the threaded component axis S1.

[0059] In one embodiment of the present invention, as Figure 2 As shown, the centering auxiliary column 300 includes a first pair of centering columns 310 and a second pair of centering columns 320, which are connected by an adjusting screw 330. That is, the distance between the first pair of centering columns 310 and the second pair of centering columns 320 is adjusted by the adjusting screw 330. This embodiment applies to a robot tightening gun 100 having two parallel nail-removing sleeves 110. By adjusting the screw 330, the first pair of centering columns 310 and the second pair of centering columns 320 are respectively positioned between the two nail-removing sleeves 110 and their corresponding nail-feeding positions E, assisting the two nail-removing sleeves 110 in positioning their movement trajectory.

[0060] Furthermore, a guide post 340 is provided between the first pair of center posts 310 and the second pair of center posts 320 for guidance. Specifically, the guide post 340 is connected to the first pair of center posts 310, the fixed end of the adjusting screw 330 is connected to the first pair of center posts 310, and the second pair of center posts 320 has a through hole and an adjusting hole. The guide post 340 passes through the through hole of the second pair of center posts 320, and the adjusting screw 330 passes through the adjusting hole of the second pair of center posts 320. Preferably, there are two guide posts 340, located above and below the adjusting screw 340 respectively, to prevent the first pair of center posts 310 and the second pair of center posts 320 from tilting during adjustment.

[0061] like Figure 3 and Figure 4 As shown, the robotic automatic bolt tightening and nail removal system of the present invention also includes a sleeve cleaning device 400. The sleeve cleaning device 400 includes a rotating head 410, a drive unit 420, and a brush head 430. The drive unit 420 drives the rotating head 410 to rotate, and the brush head 430 is connected to the rotating head 410. The rotating head 410 drives the brush head 430 to clean the nail removal sleeve 110.

[0062] The nail-removing sleeve 110 relies on magnetic force to attract bolts and nuts. Prolonged rotation can cause impurities such as iron filings to adhere to the surface of the sleeve, affecting its magnetic force and leading to nail removal failure due to insufficient magnetism. This invention addresses this by incorporating a sleeve cleaning device 400 to periodically clean the iron filings and other impurities attracted by the magnet on the surface of the nail-removing sleeve 110, thereby improving its adsorption capacity and nail removal stability. Of course, this invention is not limited to this; other cleaning devices can also be used for cleaning.

[0063] like Figure 5 and Figure 6 As shown, the robotic automatic bolt tightening and nail removal system of the present invention further includes a nail removal guide device 500. The nail removal guide device 500 includes a guide funnel 510 disposed at the nail feeding position E. The top diameter D1 of the guide funnel 510 is larger than the bottom diameter D2 of the guide funnel 510, and the bottom diameter D2 of the guide funnel 510 is adapted to the outer diameter of the nail removal sleeve 110. That is, the opening of the guide funnel 510 gradually narrows, guiding the nail removal sleeve 110 into the nail removal position E.

[0064] Furthermore, the nail-removing guide device 500 also includes a support assembly 520, through which the guide funnel 510 is disposed at the nail-feeding position E. For example, the support assembly 520 is connected to the side of the top feeding platform 210, supporting the guide funnel 510 disposed above the nail-feeding position E, so as not to affect other parts on the top feeding platform 210 at the nail-feeding position E.

[0065] like Figure 7As shown, the robot tightening gun 100 also includes a spring 120, and the nail removal sleeve 110 includes a connecting outer cylinder 111 and a rotating inner cylinder 112 rotatably connected to the connecting outer cylinder 111. The spring 120 abuts between the connecting outer cylinder 111 and the rotating inner cylinder 112.

[0066] In summary, combining Figure 9 and Figure 10 The automatic bolt tightening and removal method of the present invention includes the following steps:

[0067] S100, optimizes the nail-removing trajectory of the robot tightening gun 100, including the nail-removing position and nail-removing posture of the nail-removing sleeve 110 of the robot tightening gun 100.

[0068] S200, the surface of the nail-removing sleeve 110 of the cleaning robot tightening gun 100 is protected from weakening of the nail-removing magnetic force due to contamination of the nail-removing sleeve 110.

[0069] S300, a nail-retrieving guide device 500, wider at the top and narrower at the bottom, is provided at the nail-feeding position E of the nail-feeding station device 200. This guide device allows the rotating, centrifugal nail-retrieving sleeve 110 to accurately enter the nail-feeding position E through the nail-retrieving guide device 500 to retrieve the nail. The nail-retrieving guide device 500 can correct the positional deviation caused by the centrifugal rotation of the nail-retrieving sleeve 110 during the nail-retrieving process.

[0070] S400, such as Figure 8 As shown, regularly inspect and replace the bolt pins 220 of the nail feeding station device 200, such as... Figure 7 As shown, a spring 120 is added to the nail-removing sleeve 110 of the robot tightening gun 100, abutting between the connecting outer cylinder 111 and the rotating inner cylinder 112.

[0071] S500, rejects irregular nails, replaces batches of nails, and regularly tests the magnetic force of nail-removing sleeves, standardizes the magnetic force of different nail-removing sleeves 110, ensures that the magnetic force of the sleeves supplied by suppliers meets the requirements, and sets the magnetic force of the nail-removing sleeves to be no less than the predetermined value.

[0072] In step S100, the centering auxiliary column 300 is used to extend the threaded part axis of the nail feeding position E of the nail feeding station device 200, and the position trajectory of the robot tightening gun 100 is adjusted multiple times so that the nail taking sleeve 110 is accurately moved to the nail feeding position E and the sleeve axis S3 of the nail taking sleeve 110 is aligned with the threaded part axis S1, and finally the moving position of the robot tightening gun 100 is accurately positioned.

[0073] It should be noted that S100, S200, S300, S400 and S500 do not represent a sequential relationship between the steps.

[0074] When the robot tightening gun removes nails, there are four rotation angles for the nail removal sleeve: 90 degrees, 180 degrees, 270 degrees, 360 degrees, and a maximum of 630 degrees. Since the bolt is slightly biased in a certain direction, the nail is removed by first reversing the rotation and then rotating it forward.

[0075] In step S300, because there is a gap between the nail-removing sleeve 110 of the robot tightening gun 100 and its splined tenon when removing nails, the longer the nail-removing sleeve 110, the greater the centrifugal force and shaking. The nail-removing guide device 500 adopts a funnel shape with a large outer diameter and a small inner diameter, and the inner diameter is slightly larger than the outer diameter of the nail-removing sleeve 110. It plays a straightening role when the nail-removing sleeve 110 removes nails, thereby eliminating centrifugal force and gap shaking, and further improving the stability of the nail removal process.

[0076] In step S400, during the nail removal process of the robot tightening gun 100, such as Figure 8 As shown, the nail feeding station device 200 has a bolt pin 220 to hold the bolt in place. The easily worn bolt pin 220 should be inspected and replaced periodically. Figure 7 As shown, a spring 120 is added to the robot tightening gun 100 to prevent the nail removal sleeve 110 from shaking under the action of the spring force during the nail removal process, thus stabilizing the center of the nail removal sleeve 110.

[0077] In step S500, the bolt batch is replaced, for example, using a plug gauge to check and improve the consistency of the bolts and nuts, thus stabilizing the success rate of bolt removal. For example, a magnetic force detector can be used to periodically test the magnetic force of the bolt removal sleeve 110, so as to replace the bolt removal sleeve 110 in a timely manner if the magnetic force between the magnets weakens due to the large friction generated during the bolt removal and tightening process.

[0078] This invention improves the stability of automatic nail removal by the robot by optimizing the nail-picking trajectory of the robot tightening gun, the sleeve, the bolt, and the nail feeding station, thereby greatly increasing productivity.

[0079] Of course, the present invention may have other various embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and modifications according to the present invention, but these corresponding changes and modifications should all fall within the protection scope of the appended claims.

Claims

1. A method for automatically tightening and removing bolts using a robot, characterized in that, Includes the following steps: Optimize the nail-retrieving trajectory of the robot tightening gun, including the nail-retrieving position and posture of the nail-retrieving sleeve; clean the surface of the nail-retrieving sleeve of the robot tightening gun; install a nail-retrieving guide device (wider at the top and narrower at the bottom) at the nail-feeding position of the nail-feeding station, so that the rotating, centrifugal nail-retrieving sleeve accurately enters the nail-feeding position through the guide device to retrieve the nail; wherein, The steps for optimizing the nail-picking trajectory of the robot tightening gun also include: using a centering auxiliary column to extend the threaded component axis of the nail-feeding station device at the nail-feeding position, adjusting the point trajectory of the robot tightening gun multiple times to accurately move the nail-picking sleeve directly above the nail-feeding position, and aligning the sleeve axis of the nail-picking sleeve with the threaded component axis. The controller records and calculates the center point and the amount of wobble between the nail-picking sleeve and the bolt and nut at the nail-feeding position, and finally accurately positions and determines the location.

2. The robot-assisted automatic bolt tightening and nail removal method according to claim 1, characterized in that, It also includes the following steps: Regularly inspect and replace the bolt pins of the nail feeding station device, and add a spring to the nail-removing sleeve of the robot tightening gun.

3. The robot-assisted automatic bolt tightening and nail removal method according to claim 1, characterized in that, It also includes the following steps: Remove irregularly shaped nails and periodically test the magnetic force of the nail-removing sleeve, ensuring that the magnetic force of the nail-removing sleeve is not lower than a predetermined value.

4. A robotic automatic bolt tightening and nail removal system, comprising a robotic tightening gun, a controller, and a nail feeding station, wherein the robotic tightening gun includes a nail-removing sleeve, the nail feeding station includes a nail feeding platform, the nail feeding platform has a nail feeding position, and the nail feeding position has a threaded component axis, characterized in that, The system also includes a centering auxiliary column, which is movably disposed above the nail feeding table. The centering auxiliary column includes a centering axis, which coincides with the axis of the threaded part when the centering auxiliary column is disposed above the nail feeding table. The controller records and calculates the center point and the amount of wobble between the nail-retrieving sleeve and the bolt and nut at the nail-feeding position, and finally accurately locates and determines the position.

5. The robotic automatic bolt tightening and nail removal system according to claim 4, characterized in that, The centering auxiliary column includes a first centering column and a second centering column, which are connected by an adjusting screw.

6. The robotic automatic bolt tightening and nail removal system according to claim 4, characterized in that, It also includes a sleeve cleaning device, which includes a rotating head, a drive unit for rotating the rotating head, and a brush head connected to the rotating head.

7. The robotic automatic bolt tightening and nail removal system according to claim 4, characterized in that, It also includes a nail-removing guide device, which includes a guide funnel disposed at the nail-feeding position. The top diameter of the guide funnel is larger than the bottom diameter of the guide funnel, and the bottom diameter of the guide funnel is adapted to the outer diameter of the nail-removing sleeve.

8. The robotic automatic bolt tightening and nail removal system according to claim 7, characterized in that, The nail-removing guide device also includes a support assembly, and the guide funnel is connected to the nail-feeding position through the support assembly.

9. The robotic automatic bolt tightening and nail removal system according to any one of claims 4 to 7, characterized in that, The robot tightening gun also includes a spring component, and the nail removal sleeve includes a connecting outer cylinder and a rotating inner cylinder rotatably connected to the connecting outer cylinder, with the spring component abutting between the connecting outer cylinder and the rotating inner cylinder.

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