A cleaning device for the yaw brake disc of a wind turbine.

Abstract

This utility model discloses a cleaning device for the yaw brake disc of a wind turbine, including a mounting frame for fixed connection to the wind turbine base; a rotating cylinder, vertically oriented and fixedly connected to the mounting frame, for rotating along its own axis when the base rotates; a cleaning mechanism, symmetrically arranged in two sets about the axis of the rotating cylinder, including a mounting column located below the rotating cylinder, a connecting plate fixedly connected to one side of the mounting column via a first connecting rod, a fixing component and a scraper at the bottom of the connecting plate, the scraper being detachably connected to the connecting plate via the fixing component, and the bottom of the scraper contacting the upper surface of the yaw brake disc; and a height adjustment mechanism connected to the cleaning mechanism for driving the cleaning mechanism to rise and fall vertically to adjust the height position of the cleaning mechanism. This utility model can adjust the height position of the cleaning mechanism, has a wide range of applications, and improves the connection stability between the scraper and the connecting plate.

Description

Technical Field

[0001] This utility model relates to the field of wind power equipment technology, and in particular to a cleaning device for the yaw brake disc of a wind turbine. Background Technology

[0002] The yaw system of a wind turbine refers to the system that controls the direction of the wind turbine so that the wind direction is aligned with the leading edge of the turbine. The yaw system generally consists of a yaw gear ring, a yaw brake disc, and a yaw brake. It is an important component of the wind turbine and is used to adjust the direction of the wind turbine so that it always faces the wind and captures wind energy to the maximum extent. The lubrication method of the yaw system of a wind turbine usually adopts centralized lubrication by a yaw grease applicator. The yaw grease applicator first lubricates the yaw gear ring, and then uses the meshing action of the yaw gear ring and the yaw internal gear ring to complete the lubrication of the yaw internal gear ring. As the wind turbine operates for a long time, the waste grease on the yaw internal gear ring will be scattered on the yaw brake disc. This will cause the friction coefficient of the upper and lower surfaces of the friction plate to be different, which will eventually lead to abnormal noise and vibration when the unit yaws.

[0003] Chinese patent (CN222739769U) discloses a cleaning device for the yaw brake disc of a wind turbine, specifically disclosing that the device is mounted on the wind turbine base via a mounting bracket. The cleaning mechanism of the device is mounted on the mounting bracket and abuts against the top surface of the yaw brake disc. During the movement of the base, the yaw brake disc remains stationary, while the base drives the mounting bracket to rotate, thereby driving the cleaning mechanism to rotate. The cleaning mechanism rotates on the upper surface of the yaw brake disc, cleaning the upper surface of the yaw brake disc. However, this device still has some problems in actual use:

[0004] (1) One end of the mounting bracket in the device is fixedly connected to the base, and the other end is equipped with a cleaning mechanism. However, the vertical length of the mounting bracket is fixed, which makes the height position of the cleaning mechanism fixed. It can only clean the upper surface of the yaw brake disc at a fixed height position. In different units, there is a difference in the height difference between the base and the upper surface of the yaw brake disc. This device is not suitable for use in wind turbine units with different height differences, and its application range is small.

[0005] (2) The cleaning mechanism of the device includes a mounting plate and a scraper. The lower end face of the mounting plate is provided with a groove, and the upper end face of the scraper is provided with a slider. The mounting plate and the scraper are fixedly connected by the engagement of the groove and the slider. However, this connection method is not stable, and the scraper is easy to detach from the mounting plate, which poses a safety hazard. Utility Model Content

[0006] In view of the above-mentioned defects or deficiencies in the prior art, it is desirable to provide a cleaning device for the yaw brake disc of a wind turbine, which facilitates the replacement of scrapers and has a wider range of applications.

[0007] This utility model provides a cleaning device for the yaw brake disc of a wind turbine, characterized in that it includes:

[0008] Mounting bracket, used for fixed connection with the base of the wind turbine;

[0009] A rotating cylinder, arranged vertically and fixedly connected to the mounting frame, is used to rotate along its own axis when the base rotates;

[0010] The cleaning mechanism has two sets of components symmetrically arranged about the axis of the rotating cylinder. It includes a mounting column located below the rotating cylinder. A connecting plate is fixedly connected to one side of the mounting column via a first connecting rod. A fixing component and a scraper are provided at the bottom of the connecting plate. The scraper is detachably connected to the connecting plate via the fixing component, and the bottom of the scraper contacts the upper surface of the yaw brake disc of the wind turbine. It is used to scrape off the grease on the upper surface of the yaw brake disc when the rotating cylinder rotates along its own axis.

[0011] A height adjustment mechanism is provided on the rotating cylinder and connected to the cleaning mechanism. It is used to drive the cleaning mechanism to move up and down in the vertical direction to adjust the height position of the cleaning mechanism.

[0012] Furthermore, the fixing component includes a fixing seat fixedly disposed at the bottom of the connecting plate, the bottom of the fixing seat having a slot, the top of the scraper being fixedly connected to a locking block matching the slot, and two sets of U-shaped grooves symmetrically disposed on both sides of the slot within the fixing seat, the U-shaped grooves communicating with the slot, and elastic fixing members disposed within the U-shaped grooves for limiting and fixing the sides of the locking block.

[0013] Furthermore, the elastic fastener includes a slider, a fixing block, a pull rod, and a spring. The slider is slidably connected within the U-shaped groove. The fixing block is fixedly connected to one end of the slider near the slot, and the pull rod is fixedly connected to the other end of the slider. The spring is sleeved on the outside of the pull rod. One end of the spring is fixedly connected to the inner wall of the U-shaped groove, and the other end is fixedly connected to the slider. The two sides of the locking block are symmetrically provided with fixing grooves that match the fixing block. The elastic force of the spring can push the fixing block into the fixing groove for fixation.

[0014] Furthermore, it also includes a collection mechanism, which includes a collection box and a second connecting rod. The collection box is fixedly connected to the mounting column via the second connecting rod. The collection box is located directly below the scraper and its top is an open structure.

[0015] Furthermore, the height adjustment mechanism includes two sets of threaded cylinders rotatably disposed within the rotating cylinder in a vertical direction. The threaded cylinders are hollow inside and have openings at both ends. A threaded rod is threadedly fitted inside the threaded cylinder. A mounting plate is fixedly connected to the bottom of the threaded rod. The top of the mounting column is fixedly connected to the mounting plate. A driven gear is fixedly fitted outside the threaded cylinder. A driving gear is rotatably disposed between the two sets of driven gears. The driving gear meshes with the two sets of driven gears. The bottom center of the driving gear is rotatably connected to the inner bottom of the rotating cylinder via a rotating shaft. A rotating rod is coaxially and fixedly connected to the bottom end of the rotating shaft. A rotating handle is fixedly disposed at the bottom end of the rotating rod.

[0016] Furthermore, it also includes a locking mechanism. The rotating rod is located below the rotating cylinder. The locking mechanism includes a locking plate fixedly connected to the outer wall of the rotating rod. The locking plate has a longitudinally penetrating threaded hole. A threaded post is threadedly connected to the threaded hole. A locking post is fixedly connected to the top of the threaded rod. A locking hole matching the locking post is opened at the outer bottom of the rotating cylinder.

[0017] Compared with the prior art, the beneficial effects of this utility model are:

[0018] (1) This utility model includes a mounting frame, a rotating cylinder, a cleaning mechanism and a height adjustment mechanism. The mounting frame is fixedly connected to the base of the wind turbine. When the base rotates relative to the yaw brake disc, it can drive the rotating cylinder and the cleaning mechanism below it to move, so that the scraper in the cleaning mechanism is in contact with the upper surface of the yaw brake disc and makes a circular motion to scrape off the grease on the upper surface of the yaw brake disc. The rotating cylinder is provided with a height adjustment mechanism, which can adjust the height position of the cleaning mechanism so that it can be used for wind turbines with different height differences.

[0019] (2) In this utility model, the scraper is detachably connected to the connecting plate through a fixing component. The fixing component includes an elastic fixing member. The elastic fixing member can limit and fix both sides of the scraper, improve the connection stability between the scraper and the connecting plate, prevent the scraper from falling off during movement, and reduce safety risks.

[0020] It should be understood that the description in this utility model description section is not intended to limit the key or essential features of the embodiments of this utility model, nor is it intended to restrict the scope of this utility model. Other features of this utility model will become readily apparent from the following description. Attached Figure Description

[0021] Other features, objects, and advantages of this invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0022] Figure 1 This is a schematic diagram of the structure of the present invention and the yaw brake disc;

[0023] Figure 2 This is a schematic diagram of the overall front structure of this utility model;

[0024] Figure 3 A side view of the connecting plate, fixing components, and scraper.

[0025] Figure 4 This is a partial structural diagram of the rotating cylinder and the height adjustment mechanism;

[0026] Figure 5 This is a schematic diagram of the height adjustment mechanism;

[0027] The diagram labels are as follows: 1. Mounting bracket; 2. Rotating cylinder; 3. Cleaning mechanism; 4. Height adjustment mechanism; 5. Collection mechanism; 6. Locking mechanism; 7. Yaw brake disc.

[0028] 11. Connecting seat;

[0029] 31. Mounting column; 32. First connecting rod; 33. Connecting plate; 34. Fixing assembly; 35. Scraper;

[0030] 41. Threaded cylinder; 42. Threaded rod; 43. Mounting plate; 44. Driven gear; 45. Driving gear; 46. Rotating handle;

[0031] 51. Collection box; 52. Second connecting rod;

[0032] 61. Locking plate; 62. Threaded post; 63. Locking post;

[0033] 341. Fixed base; 342. Flexible fastener;

[0034] 351. Card block;

[0035] 3411, U-shaped groove;

[0036] 3421, slider; 3422, fixed block; 3423, pull rod; 3424, spring. Detailed Implementation

[0037] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the relevant invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, only the parts relevant to the invention are shown in the accompanying drawings.

[0038] It should be noted that, where there is no conflict, the embodiments and features in the embodiments of this utility model can be combined with each other. The present utility model will now be described in detail with reference to the accompanying drawings and embodiments.

[0039] To facilitate understanding of the technical solution, the relationship between the yaw brake disc and the base of the wind turbine is described here. The wind turbine detects the wind direction through an anemometer and sends a feedback signal to the wind turbine control system. The wind turbine control system controls the operation of the yaw system based on the feedback signal, so that the base drives the wind turbine to actively move to face the wind direction, thereby ensuring the stable operation of the wind turbine and increasing the power generation of the wind turbine. During the movement of the base, the yaw brake disc remains stationary (the two move relative to each other). This disclosure is based on this premise.

[0040] Please refer to Figures 1-5 This utility model provides a cleaning device for the yaw brake disc of a wind turbine, including a mounting frame 1, a rotating cylinder 2, a cleaning mechanism 3, and a height adjustment mechanism 4.

[0041] Mounting bracket 1 is used for fixed connection with the base of the wind turbine unit;

[0042] The rotating cylinder 2 is set vertically and fixedly connected to the mounting frame 1, and is used to rotate along its own axis when the machine base rotates;

[0043] The cleaning mechanism 3 has two sets of components symmetrically arranged about the axis of the rotating cylinder 2. It includes a mounting column 31 located below the rotating cylinder 2. A connecting plate 33 is fixedly connected to one side of the mounting column 31 via a first connecting rod 32. A fixing component 34 and a scraper 35 are provided at the bottom of the connecting plate 33. The scraper 35 is detachably connected to the connecting plate 33 via the fixing component 34. The bottom of the scraper 35 is in contact with the upper surface of the yaw brake disc 7 of the wind turbine. It is used to scrape off the grease on the upper surface of the yaw brake disc 7 when the rotating cylinder 2 rotates along its own axis.

[0044] The height adjustment mechanism 4 is mounted on the rotating cylinder 2 and connected to the cleaning mechanism 3. It is used to drive the cleaning mechanism 3 to rise and fall in the vertical direction to adjust the height position of the cleaning mechanism 3.

[0045] In this embodiment, a connecting seat 11 is fixedly connected to the end of the mounting bracket 1. The connecting seat 11 is provided with a threaded hole, and the connecting seat 11 can be fixedly installed on the base of the wind turbine by means of bolt connection. The mounting bracket 1 is provided with two sets, which increases the stability of the connection.

[0046] Two sets of cleaning mechanisms 3 are symmetrically arranged about the axis of the rotating cylinder 2. The yaw brake disc 7 is annular. The scrapers 35 in both sets of cleaning mechanisms 3 abut against the upper surface of the yaw brake disc 7. The length direction of the scraper 35 is perpendicular to its rotation direction, and the length of the scraper 35 is slightly larger than the width of the annulus of the yaw brake disc 7, so that the scraped grease and dirt can fall from both sides of the annulus. In order to improve wear resistance and avoid severe wear on the surface of the yaw brake disc 7, the scraper 35 can be made of rubber material.

[0047] When the base of the wind turbine rotates according to the wind direction, the mounting frame 1 will rotate with the base, thereby driving the rotating cylinder 2 to rotate along its own axis. During the rotation of the rotating cylinder 2, the two sets of scrapers 35 are in contact with the upper surface of the yaw brake disc 7 and make circular motion. During the rotation, the movement paths of the two sets of scrapers 35 are repeated, and the grease on the upper surface of the yaw brake disc 7 is scraped and cleaned.

[0048] Furthermore, the scraper 35 and the connecting plate 33 of this application are detachably connected by the fixing component 34, which facilitates the periodic replacement of the scraper 35, avoids the replacement of the entire device, and reduces costs. For wind turbines with a small height difference between the base and the yaw brake disc 7, the height of the cleaning mechanism 3 can be appropriately raised by the height adjustment mechanism 4. For wind turbines with a large height difference between the base and the yaw brake disc 7, the height of the cleaning mechanism 3 can be appropriately lowered by the height adjustment mechanism 4, thereby expanding the application range of this device. It is not necessary to design it separately for each unit (only for cases where the height difference changes but the annular structure of the yaw brake disc 7 remains unchanged).

[0049] In a preferred embodiment, such as Figure 2 and Figure 3 As shown, the fixing component 34 includes a fixing seat 341 fixedly disposed at the bottom of the connecting plate 33. The bottom of the fixing seat 341 is provided with a slot. The top of the scraper 35 is fixedly connected with a locking block 351 that matches the slot. Two sets of U-shaped grooves 3411 are symmetrically provided on both sides of the slot in the fixing seat 341. The U-shaped grooves 3411 are connected to the slot. An elastic fixing member 342 is provided in the U-shaped groove 3411 for limiting and fixing the two sides of the locking block 351.

[0050] Preferably, the elastic fastener 342 includes a slider 3421, a fixing block 3422, a pull rod 3423, and a spring 3424. The slider 3421 is slidably connected in the U-shaped groove 3411. The fixing block 3422 is fixedly connected to one end of the slider 3421 near the slot. The pull rod 3423 is fixedly connected to the other end of the slider 3421. The spring 3424 is sleeved on the outside of the pull rod 3423. One end of the spring 3424 is fixedly connected to the inner wall of the U-shaped groove 3411, and the other end is fixedly connected to the slider 3421. Fixing slots matching the fixing block 3422 are symmetrically opened on both sides of the locking block 351. The elastic force of the spring 3424 can push the fixing block 3422 into the fixing slot for fixation.

[0051] In this embodiment, when fixing the scraper 35, one operator first pulls the lever 3423 outward, compressing the spring 3424 and causing the fixing block 3422 to slide into the U-shaped groove 3411. Then, another operator inserts the locking block 351 at the top of the scraper 35 upward into the locking groove at the bottom of the fixing seat 341. Subsequently, the lever 3423 is released, and under the elastic force of the spring 3424, the fixing block 3422 is inserted into the fixing grooves on both sides of the locking block 351 and fixed, thus completing the fixing of the scraper 35. The structure is simple and easy to implement, facilitating disassembly and replacement, and the stability of the scraper 35 after fixing is better.

[0052] In some other preferred embodiments, multiple sets of slider 3421, fixing block 3422, pull rod 3423 and spring 3424 can be provided, and multiple sets of fixing grooves are also provided on the locking block 351. The multiple sets of fixing grooves correspond one-to-one with the multiple sets of fixing blocks 3422, which improves the stability of the scraper 35 after it is fixed. The multiple sets of pull rods 3423 located on the same side are fixedly connected by a pull plate, which makes it easy for the multiple sets of fixing blocks 3422 on the same side to move synchronously.

[0053] In a preferred embodiment, such as Figure 1 and Figure 2 As shown, it also includes a collection mechanism 5, which includes a collection box 51 and a second connecting rod 52. The collection box 51 is fixedly connected to the mounting column 31 through the second connecting rod 52. The collection box 51 is located directly below the scraper 35 and its top is an open structure.

[0054] In this embodiment, the second connecting rod 52 extends downward along the length of the mounting post 31, so that the collection box 51 is located below the lower surface of the yaw brake disc 7 and directly below the scraper 35. When the scraper 35 rotates to perform the scraping action, the collection box 51 also rotates synchronously to collect the scraped dirt.

[0055] Furthermore, the second connecting rod 52 and the mounting post 31 are detachably connected by a bolt group, which facilitates the installation of the collection box 51 below the yaw brake disc 7;

[0056] Furthermore, the opening length of the collection box 51 is greater than the annular width of the yaw brake disc 7.

[0057] In a preferred embodiment, such as Figure 2 , Figure 4 and Figure 5 As shown, the height adjustment mechanism 4 includes two sets of threaded cylinders 41 that are rotatably disposed in the rotating cylinder 2 in the vertical direction. The threaded cylinder 41 is hollow inside and has openings at both ends. A threaded rod 42 is threadedly sleeved inside the threaded cylinder 41. A mounting plate 43 is fixedly connected to the bottom of the threaded rod 42. The top of the mounting column 31 is fixedly connected to the mounting plate 43. A driven gear 44 is fixedly sleeved on the outside of the threaded cylinder 41. A driving gear 45 is rotatably disposed between the two sets of driven gears 44. The driving gear 45 meshes with the two sets of driven gears 44. The bottom center of the driving gear 45 is rotatably connected to the inner bottom of the rotating cylinder 31 through a rotating shaft. A rotating rod is coaxially connected to the bottom end of the rotating shaft. A rotating handle 46 is fixedly disposed at the bottom end of the rotating rod.

[0058] In this embodiment, when the height difference between the base and the yaw brake disc 7 is small, the height position of the cleaning mechanism 3 is appropriately raised by the height adjustment component 4; when the height difference between the base and the yaw brake disc 7 is large, the height position of the cleaning mechanism 3 is appropriately lowered by the height adjustment component 4.

[0059] When height adjustment is required, the drive gear 45 is driven to rotate by turning the handle 46. The rotation of the drive gear 45 drives the two sets of driven gears 44 meshing with it to rotate. The two sets of driven gears 44 rotate in the same direction. The rotation of the driven gears 44 in turn drives the two sets of threaded cylinders 41 to rotate in the same direction. The thread direction of the threaded rods 42 is the same. When the threaded cylinders 41 rotate forward or backward, the threaded rods 42 rise or fall, thereby driving the cleaning mechanism 3 and the collecting mechanism 5 to rise or fall, thus improving the applicability.

[0060] In a preferred embodiment, such as Figure 4 and Figure 5 As shown, it also includes a locking mechanism 6. The rotating rod is located below the rotating cylinder 2. The locking mechanism 6 includes a locking plate 61 fixedly connected to the outer wall of the rotating rod. The locking plate 61 has a longitudinal through threaded hole. A threaded post 62 is threadedly connected inside the threaded hole. A locking post 63 is fixedly connected to the top of the threaded post 62. A locking hole matching the locking post 63 is opened at the bottom of the outer side of the rotating cylinder 2.

[0061] In this embodiment, two sets of threaded posts 62 are symmetrically arranged to improve the stability after locking. After adjusting the height of the outer wall, rotating the threaded posts 62 can drive the locking posts 63 to rise until the locking posts 62 are inserted into the locking holes at the bottom of the rotating cylinder 2 and fixed, thereby locking the drive gear 45 and preventing the drive gear 45 from rotating arbitrarily due to external forces, thus fixing the height position of the cleaning mechanism 3 after adjustment.

[0062] In the description of this specification, the terms "connection," "installation," and "fixing," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0063] In the description of this specification, the terms "one embodiment," "some embodiments," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0064] The above are merely preferred embodiments of this application and are not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A cleaning device for a yaw brake disc of a wind turbine generator unit, characterized in that include: Mounting bracket, used for fixed connection with the base of the wind turbine; A rotating cylinder, arranged vertically and fixedly connected to the mounting frame, is used to rotate along its own axis when the base rotates; The cleaning mechanism has two sets of components symmetrically arranged about the axis of the rotating cylinder. It includes a mounting column located below the rotating cylinder. A connecting plate is fixedly connected to one side of the mounting column via a first connecting rod. A fixing component and a scraper are provided at the bottom of the connecting plate. The scraper is detachably connected to the connecting plate via the fixing component, and the bottom of the scraper contacts the upper surface of the yaw brake disc of the wind turbine. It is used to scrape off the grease on the upper surface of the yaw brake disc when the rotating cylinder rotates along its own axis. A height adjustment mechanism is provided on the rotating cylinder and connected to the cleaning mechanism. It is used to drive the cleaning mechanism to move up and down in the vertical direction to adjust the height position of the cleaning mechanism.

2. A wind turbine yaw brake disc cleaning device according to claim 1, wherein, The fixing component includes a fixing seat fixedly disposed at the bottom of the connecting plate. The bottom of the fixing seat has a slot. The top of the scraper is fixedly connected to a locking block that matches the slot. The fixing seat has two sets of U-shaped grooves symmetrically disposed on both sides of the slot. The U-shaped grooves are connected to the slot. The U-shaped grooves are provided with elastic fixing members for limiting and fixing the two sides of the locking block.

3. A wind turbine yaw brake disc cleaning device according to claim 2, wherein, The elastic fastener includes a slider, a fixing block, a pull rod, and a spring. The slider is slidably connected within the U-shaped groove. The fixing block is fixedly connected to one end of the slider near the slot, and the pull rod is fixedly connected to the other end of the slider. The spring is sleeved on the outside of the pull rod. One end of the spring is fixedly connected to the inner wall of the U-shaped groove, and the other end is fixedly connected to the slider. The two sides of the locking block are symmetrically provided with fixing grooves that match the fixing block. The elastic force of the spring can push the fixing block into the fixing groove for fixation.

4. A wind turbine yaw brake disc cleaning device according to claim 1, wherein, It also includes a collection mechanism, which includes a collection box and a second connecting rod. The collection box is fixedly connected to the mounting column via the second connecting rod. The collection box is located directly below the scraper and its top is an open structure.

5. A wind turbine yaw brake disc cleaning device according to claim 4, wherein, The height adjustment mechanism includes two sets of threaded cylinders rotatably disposed within the rotating cylinder in a vertical direction. The threaded cylinders are hollow inside and have openings at both ends. A threaded rod is threadedly fitted inside the threaded cylinder. A mounting plate is fixedly connected to the bottom of the threaded rod. The top of the mounting column is fixedly connected to the mounting plate. A driven gear is fixedly fitted outside the threaded cylinder. A driving gear is rotatably disposed between the two sets of driven gears. The driving gear meshes with the two sets of driven gears. The bottom center of the driving gear is rotatably connected to the inner bottom of the rotating cylinder via a rotating shaft. A rotating rod is coaxially and fixedly connected to the bottom end of the rotating shaft. A rotating handle is fixedly disposed at the bottom end of the rotating rod.

6. A wind turbine yaw brake disc cleaning device according to claim 5, wherein, It also includes a locking mechanism. The rotating rod is located below the rotating cylinder. The locking mechanism includes a locking plate fixedly connected to the outer wall of the rotating rod. The locking plate has a longitudinally penetrating threaded hole. A threaded post is threadedly connected to the threaded hole. A locking post is fixedly connected to the top of the threaded rod. A locking hole matching the locking post is opened at the outer bottom of the rotating cylinder.

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