Safety position intelligent monitoring lifting appliance system for steel coil lifting

Abstract

The invention discloses a safety position intelligent monitoring lifting appliance system for steel coil lifting, and belongs to the technical field of steel coil lifting, the safety position intelligent monitoring lifting appliance system comprises a travelling crane frame and a moving platform capable of translating on the travelling crane frame, an electric rope disc is mounted on the moving platform, and a steel rope on the electric rope disc is connected with a positioning lifting hook; a visual detection module and a distance measuring sensor are mounted on the positioning lifting hook, the visual detection module and the distance measuring sensor are connected with a controller, and the output end of the controller is connected with the input end of an image processing unit and the input end of a distance measuring calculation unit. According to the safe position intelligent monitoring lifting appliance system for steel coil lifting, through the arrangement of the distance measuring sensor and the visual detection module, the distance between a worker and a lifting appliance in the moving process can be monitored, meanwhile, the visual detection module is used for shooting people and objects around the lifting appliance, when an operator operates mistakenly, alarm reminding can be conducted, and the safety of the lifting appliance is improved. The operation safety of personnel is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of steel coil hoisting, and in particular to a safety position intelligent monitoring hoisting device system for steel coil hoisting. Background Art

[0002] When processing steel coils, they need to be sheared, stamped, and other processes. However, during the shearing or stamping process, the steel coils need to be moved to the corresponding processing stations. In order to facilitate the lifting and transportation of the steel coils, most of the time, corresponding cranes are required to achieve the transfer of the steel coils.

[0003] For example, the Chinese patent with the publication number CN219194197U, titled "A C-type sling for stably lifting steel coils," and the publication date 2023-06-16, includes a sling body, a lifting lug and a counterweight provided on the top of the sling body, a rotating shaft rotatably provided on the inner upper portion of the sling body, a limit rod rotating with the rotating shaft provided on the rotating shaft, and a driving mechanism for driving the rotating shaft to rotate provided on the lower side of the counterweight. The above-mentioned prior art has the following technical problems: When existing steel coil hoists are lifting steel coils, it is not convenient to monitor people and objects around the hoist. When the operator makes an error in operation, it is not convenient to issue an alarm. At the same time, when the hoist is moving, it is not convenient to measure the safe distance between the hoist and the person in real time when the person is walking. When the staff makes an error in operation or the distance between the staff and the moving hoist is too close, it is easy to cause dangerous accidents, thereby reducing the safety of the staff.

[0004] Therefore, we proposed a safe position intelligent monitoring sling system for steel coil hoisting to solve the above problems. Summary of the Invention

[0005] The purpose of the present invention is to provide a safe position intelligent monitoring sling system for steel coil hoisting, so as to solve the problem raised in the above background technology that the existing steel coil slings on the market are not convenient for monitoring people and objects around the slings when hoisting steel coils, and it is not convenient to issue an alarm when the operator makes an error in operation. At the same time, when the sling is moving, it is not convenient to measure the safe distance between the sling and the person in real time when the person is walking. When the staff makes an error in operation or the distance between the staff and the moving sling is too close, it is easy to cause dangerous accidents, thereby reducing the safety of the staff.

[0006] To achieve the above-mentioned objectives, the present invention provides the following technical solutions: a safe position intelligent monitoring sling system for steel coil lifting, comprising a traveling frame and a mobile platform capable of translating on the traveling frame, an electric rope drum being installed on the mobile platform, and the steel cable on the electric rope drum being interconnected with the positioning hook, a visual detection module and a ranging sensor being installed on the positioning hook, and the visual detection module and the ranging sensor being interconnected with a controller, an output end of the controller being respectively connected to an input end of an image processing unit and a ranging calculation unit, and the image processing unit and the ranging calculation unit being electrically connected to a data comparison module, an output end of the data comparison module being interconnected with an input end of an alarm unit, and the alarm unit being used to alert staff members of a safety signal through an alarm.

[0007] Preferably, the data comparison module is used to compare the data input by the image processing unit and the distance calculation unit with the safety threshold and the image, and the alarm unit connected to the data comparison module is configured as an audible and visual alarm.

[0008] By adopting the above technical solution, the data comparison module is set up to facilitate the measurement of data, and by comparing with the safety threshold, automatic alarm reminders of dangerous distances and improper human operations are realized.

[0009] Preferably, a dual-axis motor is installed inside the positioning hook, and one-way rotating parts are installed on the output shafts at both ends of the dual-axis motor. The one-way rotating part on the output shaft at the right end of the dual-axis motor is connected to the center shaft, and a branch block is installed on the center shaft. An electromagnet is installed in the middle part of the inner side of the center shaft, and a plug-in cross bar is provided on the side of the electromagnet. The plug-in cross bar is connected to the center shaft through a built-in spring, and a power magnetic block is fixed on the end of the plug-in cross bar close to the electromagnet. The end of the plug-in cross bar away from the electromagnet extends out of the center shaft and is inserted into the docking hole inside the branch block.

[0010] By adopting the above technical solution, the internal spring is provided so that the plug-in cross bar can be reset and rebound after moving on the central axis.

[0011] Preferably, a plurality of branch blocks are evenly distributed on the central axis, and the contact surfaces between the central axis and the branch blocks are both rough surfaces, and the branch blocks can rotate on the central axis.

[0012] By adopting the above technical solution, the contact surfaces of the central shaft and the branch blocks are rough surfaces, thereby increasing the friction between the two, so that the central shaft can use the friction force to drive the branch blocks to rotate synchronously when rotating.

[0013] Preferably, the upper surface of the branch block and the lower end of the positioning hook are flush with each other, and the inner wall of the internal docking hole of the branch block and the outer wall of the end of the plug-in cross bar are in contact with each other.

[0014] By adopting the above technical solution, the lower ends of the branch block and the positioning hook are flush with each other, so that when the steel coil is hoisted, the steel coil can be simultaneously overlapped on the branch block and the positioning hook.

[0015] Preferably, the power magnetic block at the end of the plug-in cross bar has the same magnetic properties as the electromagnet after power is supplied, and the plug-in cross bar and the central axis are in sliding connection.

[0016] By adopting the above technical solution, the repulsive magnetic force generated by the electromagnet on the power magnetic block can enable the plug-in cross bar to move on the central axis, thereby facilitating the plug-in cross bar to be inserted into the docking hole.

[0017] Preferably, the unidirectional rotating component shaft on the left end output shaft of the dual-axis motor is connected to a driving gear, and a limiting gear rack is provided on the outside of the driving gear, and the upper and lower ends of the limiting gear rack are respectively fixed with an upper pressure plate and a lower pressure plate, and the upper pressure plates are connected to each other through a reset spring and a positioning hook.

[0018] By adopting the above technical solution, the engaging limiting gear rack can be moved in the vertical direction by driving the rotation of the gear.

[0019] Preferably, the position-limiting gear rack can slide on the positioning hook, and the upper pressing plate and the lower pressing plate at the upper and lower ends of the position-limiting gear rack are distributed in parallel.

[0020] By adopting the above technical solution, the limiting gear rack moves downward, so that the lower pressure plate can contact the bottom of the inner ring of the steel coil, and the upper pressure plate can contact the upper end of the outer ring of the steel coil.

[0021] Preferably, the unidirectional rotating parts at the left and right ends of the dual-axis motor rotate and lock in opposite directions. The unidirectional rotating parts include a ratchet, and a ratchet groove is provided circumferentially on the inner ring of the ratchet. Ratchet teeth are provided on the inner side of the ratchet groove, and the ratchet teeth are installed on the rotating shaft circumferentially of the guide plate. The ratchet teeth are connected to each other through an auxiliary spring and the guide plate.

[0022] By adopting the above technical solution, the one-way rotating component rotates in opposite locking directions, so that when the dual-axis motor controls the output shaft to rotate forward or reverse, only one of the drive gear and the center shaft can rotate.

[0023] Compared with the existing technology, the beneficial effects of the present invention are as follows: the intelligent monitoring system for safe position of steel coil hoisting can monitor the distance between the operator and the spreader during movement through the setting of the distance measuring sensor and the visual detection module, and at the same time use the visual detection module to photograph people and objects around the spreader. When the operator makes an erroneous operation, an alarm can be issued to improve the operator's operating safety; 1. It is equipped with a visual detection module and a distance measurement sensor. The visual detection module can monitor people and objects around the spreader, thereby recording any misoperation by the staff and then using the alarm unit to issue an alarm reminder. At the same time, when the spreader is moving, the distance measurement sensor can monitor the safe distance between the staff and the spreader when manipulating the spreader. When the distance is too close, the alarm unit will also issue an alarm reminder, thus forming an intelligent safety position monitoring system to improve the safety of personnel operation; 2. A branch block is provided. After the positioning hook is inserted into the steel coil, the central shaft is controlled by a dual-axis motor to drive the branch block to rotate. Because there are multiple branch blocks, the branch block pressed by the steel coil cannot rotate with the central shaft when the central shaft rotates, while the branch block not pressed by the steel coil rotates with the central shaft under the action of friction damping. The rotated branch block will block the steel coil to prevent it from being unhooked. The setting of multiple branch blocks can adaptively adjust the blocking position according to steel coils of different widths. 3. A plug-in crossbar is provided. When the branch block rotates into position along with the central axis, the electromagnet is energized to generate a repulsive magnetic force on the power magnetic block, thereby causing the plug-in crossbar to move toward the outside of the central axis under the action of the magnetic force and insert into the docking hole inside the branch block, thereby limiting the position of the rotated branch block and preventing the branch block from rotating on its own due to factors such as shaking when lifting the steel coil; 4. A limit gear rack is set up. The limit gear rack can be moved downward by rotating the driving gear. After the limit gear rack moves downward, the upper pressure plate and the lower pressure plate can be moved downward synchronously. After the upper pressure plate moves downward, it can contact and press the outer ring of the steel coil, and after the lower pressure plate moves downward, it will contact the bottom of the inner ring of the steel coil, so as to further improve the locking stability of the steel coil lifting, prevent the steel coil from being unhooked due to shaking or other factors during the lifting process, and improve the safety of the steel coil during lifting. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a schematic diagram of the front three-dimensional structure of the present invention; Figure 2 Schematic diagram of the control system of the present invention; Figure 3 This is a schematic diagram of the structure of the visual detection module and the ranging sensor of the present invention; Figure 4 This is a schematic diagram of the positioning hook and lower pressure plate structure of the present invention; Figure 5 This is a schematic diagram of the electromagnet and the plug-in crossbar structure of the present invention; Figure 6 This is a schematic diagram of the structure of the dual-axis motor and the unidirectional rotating component of the present invention; Figure 7 This is a schematic diagram of the ratchet and guide disc structure of the present invention; Figure 8 For the present invention Figure 7 A in the middle is an enlarged structural diagram; Figure 9 This is a schematic diagram of the structure of the driving gear and the limiting gear rack of the present invention.

[0025] In the figure: 1. Travel frame; 2. Mobile platform; 3. Electric rope drum; 4. Positioning hook; 5. Visual detection module; 6. Distance measurement sensor; 7. Alarm unit; 8. Dual-axis motor; 9. One-way rotating component; 901. Ratchet; 902. Ratchet groove; 903. Ratchet; 904. Auxiliary spring; 905. Guide plate; 10. Center shaft; 11. Branch block; 12. Electromagnet; 13. Plug-in cross bar; 14. Built-in spring; 15. Power magnetic block; 16. Docking hole; 17. Drive gear; 18. Limiting gear rack; 19. Upper pressure plate; 20. Lower pressure plate; 21. Reset spring; 22. Tilt detection level. DETAILED DESCRIPTION

[0026] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0027] Example 1: Please refer to Figures 1-9When the existing steel coil hoist is used to hoist the steel coil, it is not convenient to monitor the people and objects around the hoist. When the operator makes an error in operation, it is not convenient to issue an alarm. At the same time, when the hoist is moving, it is not convenient to measure the safe distance between the hoist and the person in real time when the person is walking. When the staff makes an error in operation or the distance between the staff and the moving hoist is too close, it is easy to cause a dangerous accident, thereby reducing the safety of the staff. In order to solve this technical problem, the following technical content is disclosed in this embodiment: a safe position intelligent monitoring hoist for steel coil hoisting The system includes a traveling frame 1 and a mobile platform 2 that can move horizontally on the traveling frame 1, an electric rope drum 3 is installed on the mobile platform 2, and the steel cable on the electric rope drum 3 is connected to the positioning hook 4, and the positioning hook 4 is installed with a visual detection module 5 and a distance sensor 6, and the visual detection module 5 and the distance sensor 6 are connected to the controller, the output end of the controller is respectively connected to the input end of the image processing unit and the distance calculation unit, and the image processing unit and the distance calculation unit are electrically connected to the data comparison module, and the output end of the data comparison module is connected to the input end of the alarm unit 7. The ends are interconnected, and the alarm unit 7 is used to alert the staff through an alarm. The data comparison module is used to compare the data input by the image processing unit and the distance calculation unit with the safety threshold and the image. The alarm unit 7 connected to the data comparison module is configured to be an audible and visual alarm. A tilt detection level 22 is installed on the upper side of the positioning hook 4. The tilt detection level 22 is used to monitor the horizontality of the positioning hook 4 during manual adjustment. At the same time, the tilt detection level 22 is electrically connected to the alarm unit 7. When the positioning hook 4 tilts during manual operation, the tilt detection level 22 can monitor the tilt. The monitored data is transmitted to the data comparison module and compared with the specified safe tilt data. When the positioning hook 4 is tilted within the safe range, the alarm unit 7 will not issue an alarm reminder, so that subsequent lifting operations can proceed normally. When the manual operation causes the tilt of the positioning hook 4 to be too large, so that there is a risk of excessive center of gravity deviation in the subsequent steel coil lifting, the alarm unit 7 will issue an audible and visual alarm, thereby giving the staff a reminder to adjust the positioning hook 4 in time, thereby improving the overall operation safety.

[0028] When the steel coil needs to be lifted, the controller is connected to the network through the communication module. When the staff operates the steel coil to lift, the visual detection module 5 on the positioning hook 4 can be used to visually monitor the staff's operation. The image captured by the visual monitoring is processed by the image processing unit and sent to the data comparison module. The data comparison module compares the operation with the operation in the database. When the staff makes an erroneous operation, the alarm unit 7 can be used to issue an audible and visual alarm reminder. At the same time, during the lifting of the steel coil, the distance between the staff and the positioning hook 4 can be recorded by the ranging sensor 6 on the positioning hook 4. The ranging sensor 6 transmits the recorded distance data to the data comparison module. The data comparison module compares the data information with the safety threshold distance. When the safety distance is exceeded, the alarm unit 7 can also be used to alarm. Therefore, the visual detection module 5 and the ranging sensor 6 can be used to monitor the lifting and transfer of steel coils, thereby preventing safety accidents caused by erroneous operation and too close distance to the greatest extent, forming an intelligent safety position monitoring system.

[0029] Embodiment 2: The technical content disclosed in this embodiment is a further improvement made on the basis of the above-mentioned embodiment 1. The following technical content is disclosed in this embodiment: a dual-axis motor 8 is installed inside the positioning hook 4, and a one-way rotating component 9 is installed on the output shafts at both ends of the dual-axis motor 8. The one-way rotating component 9 on the right end output shaft of the dual-axis motor 8 is connected to the central shaft 10, and a branch block 11 is installed on the central shaft 10. An electromagnet 12 is installed in the middle of the inner side of the central shaft 10, and a plug-in cross bar 13 is provided on the side of the electromagnet 12. The plug-in cross bar 13 is connected to the central axis 10 through a built-in spring 14, and a power magnetic block 15 is fixed to the end of the plug-in cross bar 13 close to the electromagnet 12. The end of the plug-in cross bar 13 away from the electromagnet 12 extends out of the central axis 10 and is inserted into the docking hole 16 inside the branch block 11. There are multiple branch blocks 11 evenly distributed on the central axis 10, and the contact surfaces between the central axis 10 and the branch blocks 11 are both set to rough surfaces, and the branch blocks 11 can rotate on the central axis 10. The upper surface of the branch block 11 and the lower end of the positioning hook 4 are mutually The inner wall of the docking hole 16 inside the branch block 11 and the outer wall of the end of the plug-in cross bar 13 fit together. The power magnetic block 15 at the end of the plug-in cross bar 13 has the same magnetic property as the electromagnet 12 after power is energized, and the plug-in cross bar 13 and the central axis 10 are connected in a sliding manner. The one-way rotating component 9 on the left end output shaft of the dual-axis motor 8 is connected to the driving gear 17, and a limiting gear rack 18 is provided on the outside of the driving gear 17. The upper and lower ends of the limiting gear rack 18 are respectively fixed with an upper pressure plate 19 and a lower pressure plate 20, and the upper pressure plate 19 is fixed by a reset spring 21 and a positioning The hooks 4 are connected to each other, the limiting gear rack 18 can slide on the positioning hook 4, and the upper pressure plate 19 and the lower pressure plate 20 at the upper and lower ends of the limiting gear rack 18 are distributed in parallel, and the unidirectional rotating parts 9 at the left and right ends of the dual-axis motor 8 rotate and lock in opposite directions. The unidirectional rotating parts 9 include a ratchet 901, and a ratchet groove 902 is circumferentially provided on the inner ring of the ratchet 901. A ratchet 903 is provided on the inner side of the ratchet groove 902, and the ratchet 903 is installed on the circumferential rotating shaft of the guide plate 905. The ratchet 903 is connected to each other through an auxiliary spring 904 and the guide plate 905.

[0030] When the steel coil needs to be lifted, the positioning hook 4 is inserted into the steel coil, and then the double-axis motor 8 is turned on. After the double-axis motor 8 is turned on, it rotates in the opposite direction. Because the rotation locking directions of the one-way rotating parts 9 at the left and right ends of the double-axis motor 8 are opposite, when the double-axis motor 8 controls the output shaft to rotate in the opposite direction, the central shaft 10 on the right output shaft of the double-axis motor 8 will not rotate, and the left output shaft of the double-axis motor 8 can drive the driving gear 17 to rotate under the action of the one-way rotating part 9. When the driving gear 17 rotates, the meshing limit gear rack 18 can be moved downward, and the limit gear rack 18 can be moved downward. It can drive the upper and lower pressure plates 19 and the lower pressure plates 20 at the upper and lower ends to move synchronously. At this time, the upper pressure plate 19 can resist and press the outer ring of the steel coil after moving downward, and the lower pressure plate 20 can resist and press the inner ring of the steel coil after moving downward, thereby realizing automatic limiting of the steel coil. After positioning the steel coil, the dual-axis motor 8 controls the output shaft to rotate forward. At this time, the driving gear 17 will not rotate under the action of the one-way rotating component 9, and the central shaft 10 on the right output shaft of the dual-axis motor 8 can rotate normally, because a rotatable branch block 11 is installed on the central shaft 10, and the central shaft 10 and the branch block 1 1, so the central shaft 10 can normally drive the branch block 11 to rotate when it rotates, and the branch block 11 on the central shaft 10 that is pressed by the steel coil will not rotate, and the branch block 11 that is not pressed by the steel coil will rotate 180 degrees with the central shaft 10, and the steel coil is blocked by the rotated branch block 11 to prevent the steel coil from being unhooked during lifting. When some branch blocks 11 rotate to block the steel coil, the electromagnet 12 is energized, and the electromagnet 12 can generate a repulsive magnetic force on the power magnetic block 15 after being energized. At this time, the power magnetic block 15 and the plug-in cross bar 13 will move toward the central shaft. The outer side of the core shaft 10 is moved, so that the plug-in cross bar 13 is inserted into the docking hole 16 inside the branch block 11, thereby fixing the branch block 11 and avoiding the failure of the blocking caused by the self-rotation of the branch block 11 due to factors such as shaking during the lifting process when the steel coil is lifted. The one-way rotating component 9 is a prior art, and the principle of one-way locking is: the guide disk 905 can make the ratchet 903 rotate synchronously when rotating. At this time, the ratchet 903 can only rotate in one direction due to the ratchet groove 902 inside the ratchet wheel 901, and is locked in the other direction, thereby achieving the purpose of one-way rotation.

[0031] The contents not described in detail in this specification belong to the prior art known to those skilled in the art.

[0032] Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A steel coil hoisting safety position intelligent monitoring sling system, comprising a traveling frame (1) and a mobile platform (2) capable of translating on the traveling frame (1), an electric rope drum (3) being installed on the mobile platform (2), and a steel cable on the electric rope drum (3) being connected to a positioning hook (4), characterized in that: The positioning hook (4) is equipped with a visual detection module (5) and a distance measuring sensor (6), and the visual detection module (5) and the distance measuring sensor (6) are interconnected with a controller, the output end of the controller is respectively connected to the input end of the image processing unit and the distance measuring calculation unit, and the image processing unit and the distance measuring calculation unit are electrically connected to the data comparison module, the output end of the data comparison module is interconnected with the input end of the alarm unit (7), and the alarm unit (7) is used to give a safety signal to the staff in the form of an alarm to remind them.

2. The intelligent monitoring system for safe position of steel coil hoisting according to claim 1 is characterized by: The data comparison module is used to compare the data input by the image processing unit and the distance measurement calculation unit with the safety threshold and the image, and the alarm unit (7) connected to the data comparison module by telecommunications is set to an audible and visual alarm.

3. The intelligent monitoring system for safe position of steel coil hoisting according to claim 1 is characterized in that: A double-axis motor (8) is installed inside the positioning hook (4), and a one-way rotating component (9) is installed on the output shafts at both ends of the double-axis motor (8). The one-way rotating component (9) on the output shaft at the right end of the double-axis motor (8) is connected to a central shaft (10), and a branch block (11) is installed on the central shaft (10). An electromagnet (12) is installed in the middle of the inner side of the central shaft (10), and a plug-in cross bar (13) is arranged on the side of the electromagnet (12). The plug-in cross bar (13) and the central shaft (10) are connected to each other through a built-in spring (14), and a power magnetic block (15) is fixed to one end of the plug-in cross bar (13) close to the electromagnet (12), and one end of the plug-in cross bar (13) away from the electromagnet (12) extends out of the central shaft (10) and is inserted into a docking hole (16) inside the branch block (11).

4. The intelligent monitoring system for safe position of steel coil hoisting according to claim 3 is characterized by: A plurality of branch blocks (11) are evenly distributed on the central axis (10), and the contact surfaces between the central axis (10) and the branch blocks (11) are both configured as rough surfaces, and the branch blocks (11) are capable of rotating on the central axis (10).

5. The intelligent monitoring system for safe position of steel coil hoisting according to claim 3 is characterized by: The upper surface of the branch block (11) and the lower end of the positioning hook (4) are flush with each other, and the inner wall of the internal docking hole (16) of the branch block (11) and the outer wall of the end of the plug-in cross bar (13) are in contact with each other.

6. The intelligent monitoring system for safe position of steel coil hoisting according to claim 3 is characterized by: The power magnetic block (15) at the end of the plug-in crossbar (13) has the same magnetic properties as the electromagnet (12) after power is supplied, and the plug-in crossbar (13) and the central shaft (10) are slidably connected.

7. The intelligent monitoring system for safe position of steel coil hoisting according to claim 3 is characterized by: The rotating shaft of the unidirectional rotating component (9) on the output shaft at the left end of the dual-axis motor (8) is connected to a driving gear (17), and a limit gear rack (18) is arranged outside the driving gear (17), and an upper pressure plate (19) and a lower pressure plate (20) are fixed to the upper and lower ends of the limit gear rack (18), respectively, and the upper pressure plate (19) is connected to each other through a return spring (21) and a positioning hook (4).

8. The intelligent monitoring system for safe position of steel coil hoisting according to claim 7 is characterized in that: The position-limiting gear rack (18) is capable of sliding on the positioning hook (4), and the upper pressing plate (19) and the lower pressing plate (20) at the upper and lower ends of the position-limiting gear rack (18) are distributed in parallel.

9. The intelligent monitoring system for safe position of steel coil hoisting according to claim 7, characterized in that: The one-way rotating parts (9) at the left and right ends of the dual-axis motor (8) rotate and lock in opposite directions. The one-way rotating parts (9) include a ratchet (901), and a ratchet groove (902) is circumferentially provided on the inner ring of the ratchet (901). A ratchet tooth (903) is provided on the inner side of the ratchet groove (902). The ratchet tooth (903) is mounted on a rotating shaft circumferentially of a guide plate (905). The ratchet tooth (903) is connected to the guide plate (905) via an auxiliary spring (904).

Images