A steel strand unwinding device

Abstract

This utility model relates to the technical field of strand unwinding devices. It provides a strand unwinding device for steel strands, comprising a fixed reel with telescopic mechanisms installed at its center and on its left and right sides. These telescopic mechanisms adjust the length of the reel. Each telescopic mechanism includes a rotating shaft that extends through the interior of the fixed reel. Two hydraulic push rods are installed at the center of the outer side of the fixed reel, with fixed push plates fixedly connected to their left and right ends. Movable reels are fixedly connected to the outer walls of the two fixed push plates. In this utility model, the hydraulic push rods push the fixed push plates, causing the movable reel to slide back and forth along the inner wall of the fixed reel, adjusting the overall length to fit the steel strand. This mechanism replaces the integrated reel with a modular telescopic reel, allowing for length adjustment without the need for complete disassembly and replacement, thus solving the problems of cumbersome operation, low efficiency, high cost, and low safety in existing technologies.

Description

Technical Field

[0001] This utility model relates to the field of strand unwinding device technology, specifically to a strand unwinding device for steel strands. Background Technology

[0002] A steel strand unwinding device is a specialized piece of equipment used in bridge, building and other engineering projects for the unwinding and bundling of steel strands. Its core function is to release coiled or reeled steel strands smoothly and orderly, avoiding problems such as twisting, tangling, damage or uneven stress during the unwinding process, thus ensuring the safety and accuracy of prestressed construction. Its main structure includes a frame, unwinding reel, bearings and rotating devices, braking and speed regulating devices, conductor and straightening components, and auxiliary support and fixing components.

[0003] Traditional steel strand unwinding devices use fixed-size drums, making it difficult to adapt to reels of different widths and diameters. Frequent drum changes are necessary during construction, consuming time and labor, and significantly reducing efficiency. To address this, existing technologies have attempted improvements using a split-type drum design. This involves replacing drum components of different specifications to fit the steel strand reels, preparing reels of varying diameters and auxiliary support devices according to the required steel strand specifications. However, in practice, this solution is cumbersome to change, and the installation accuracy of different components is difficult to guarantee, greatly reducing work efficiency. Frequent changes also consume significant manpower, increasing labor costs. Furthermore, the weight and rigidity of the steel strands themselves pose a safety hazard to operators during changes, reducing overall safety during construction. Utility Model Content

[0004] To overcome the above-mentioned defects, this utility model provides a steel strand unbundling device, which solves the technical problems of the prior art, such as cumbersome operation process, reduced work efficiency, increased labor costs, hazard to the personal safety of operators, and reduced safety during construction.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: a steel strand unwinding device, comprising a fixed reel, wherein telescopic mechanisms are installed in the middle and on the left and right sides of the fixed reel, the telescopic mechanisms being used to adjust the length of the reel; a support mechanism is installed at the bottom of the fixed reel, the support mechanism being used to support the fixed reel and the telescopic mechanisms; the telescopic mechanism includes a rotating shaft that passes through the interior of the fixed reel; two hydraulic push rods are installed in the middle of the outer side of the fixed reel; fixed push plates are fixedly connected to the left and right ends of the two hydraulic push rods; movable reels are fixedly connected to the outer walls of the two fixed push plates; limit plates are installed on the left and right sides of the two movable reels; and fine-tuning components are fixedly connected to the left and right sides of the two movable reels.

[0006] As a further description of the above technical solution:

[0007] The fine-tuning assembly includes two fine-tuning plates, both of which are slidably connected to the outer walls of the left and right ends of the rotating shaft. Compression springs are fixedly connected to the outer walls of the left and right sides of the two fine-tuning plates at equal intervals.

[0008] As a further description of the above technical solution:

[0009] The support mechanism includes a fixed frame, which is installed on the left and right sides of the fixed roll. Connecting strips are fixedly connected to the front and rear sides of the bottom of the fixed frame, and reinforcing strips are fixedly connected to the left and right sides of the bottom of the fixed frame. Bearing components are installed on the bottom of the outer walls of the two movable rolls.

[0010] As a further description of the above technical solution:

[0011] The bearing assembly includes a friction wheel, which is engaged with the bottom of the outer wall of the limiting plate. Tripods are installed on both the left and right sides of the friction wheel. Pulleys are rotatably connected to the front and rear sides of the two tripods. Slide rails are fixedly connected to the top of the two connecting bars. The pulleys are rotatably connected to the top of the outer wall of the slide rails.

[0012] As a further description of the above technical solution:

[0013] A second rotating shaft is fixedly connected to the middle of the friction wheel, and a second bearing is rotatably connected to both the left and right ends of the second rotating shaft. The second bearing is fixedly connected to the top of the tripod, and the friction wheel is rotatably connected to the top of the tripod through the second bearing.

[0014] As a further description of the above technical solution:

[0015] The fixed push plate and the fine-tuning plate are slidably connected to the left and right sides of the outer wall of the rotating shaft, and the limiting plate is fixedly connected to the left and right ends of the outer wall of the rotating shaft.

[0016] As a further description of the above technical solution:

[0017] Multiple anti-slip teeth are fixedly connected to the middle of the outer wall of the friction wheel, and wheel frames are fixedly connected to the front and rear ends of the tripod. The pulley is rotatably connected to the middle of the wheel frame.

[0018] As a further description of the above technical solution:

[0019] A motor bracket is provided at the bottom left side of the fixed roller, and a drive motor is fixedly connected to the top of the motor bracket. The output end of the drive motor is fixedly connected to the left end of the rotating shaft.

[0020] Each of the left and right ends of the rotating shaft is rotatably connected to a bearing. Both bearings are fixedly connected to the top of the mounting frame. The rotating shaft is rotatably connected to the top of the mounting frame via the bearings.

[0021] A mounting column is rotatably connected to the middle of the outer wall of the rotating shaft, and the two hydraulic push rods are fixedly connected to the left and right outer walls of the mounting column.

[0022] The beneficial effects of the embodiments of this utility model are as follows:

[0023] In this invention, a hydraulic push rod drives a fixed push plate, which in turn drives a movable reel to slide back and forth on the inner wall of the fixed reel to adjust the overall length to fit the steel strand. A limiting plate prevents the steel strand from tangling and misaligning during winding and unwinding. The fine-tuning component between the limiting plate and the steel strand achieves adaptive fine-tuning when the steel strand squeezes the fine-tuning plate and compresses the compression spring. This mechanism replaces the integrated reel with a modular telescopic reel, allowing for length adjustment as needed without the need for complete disassembly and replacement. This solves the problems of cumbersome operation, low efficiency, high cost, and low safety in existing technologies.

[0024] The fixed frame axially fixes the hydraulic push rod to ensure stable rotation of the telescopic mechanism. The ring-shaped rib of the limiting plate engages with the groove of the friction wheel. The friction wheel is supported by a tripod, which contacts the connecting strip through pulleys. When the length of the telescopic mechanism is adjusted, the limiting plate moves with the movable roller, driving the friction wheel and the tripod to move on the slide rail through the pulleys. When the fixed roller and the telescopic mechanism rotate, the limiting plate drives the friction wheel to rotate on the top of the tripod to avoid interference. This mechanism provides dynamic adaptive support for the telescopic mechanism and improves the overall stability of the equipment. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of this utility model, the accompanying drawings used in the description of the embodiments of this utility model will be briefly introduced below. Obviously, the drawings described below are merely some exemplary embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the content of the exemplary embodiments of this utility model and these drawings without any creative effort.

[0026] Figure 1 This is a front view of a steel strand unwinding device proposed in this utility model;

[0027] Figure 2 This is a perspective view of a steel strand unbundling device proposed in this utility model;

[0028] Figure 3 This is an exploded view of the telescopic mechanism of a steel strand unbundling device proposed in this utility model;

[0029] Figure 4 This is an exploded view of the support mechanism of a steel strand unbundling device proposed in this utility model;

[0030] Figure 5 This is an exploded view of the supporting component of a steel strand unwinding device proposed in this utility model.

[0031] In the picture:

[0032] 1. Fixed reel; 2. Telescopic mechanism; 201. Rotating shaft one; 202. Hydraulic push rod; 203. Fixed push plate; 204. Movable reel; 205. Limiting plate; 206. Fine-tuning component; 2061. Fine-tuning plate; 2062. Compression spring; 3. Support mechanism; 301. Fixed frame; 302. Connecting bar; 303. Reinforcing bar; 304. Bearing component; 3041. Friction wheel; 3042. Tripod; 3043. Pulley; 3044. Slide rail; 4. Drive motor; 5. Motor bracket; 6. Anti-slip teeth; 7. Wheel frame; 8. Bearing one; 9. Bearing two; 10. Rotating shaft two; 11. Mounting column. Detailed Implementation

[0033] 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 present invention and not intended to limit its scope.

[0034] To keep the drawings concise, only the parts relevant to the utility model are shown schematically in each drawing; these do not represent the actual structure of the product. Furthermore, for ease of understanding, in some drawings, only one of the components with the same structure or function is schematically shown, or only one is labeled. In this document, "a" not only means "only one," but can also mean "more than one," and "several" includes "two" and "more than two."

[0035] In this document, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0036] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0037] In the description of this embodiment, terms such as "upper," "lower," "left," and "right" are based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of description and simplification of operation, and are not intended to 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 utility model.

[0038] Furthermore, in the description of this application, the terms "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0039] Reference Figure 1 , Figure 2 and Figure 3 An embodiment of this utility model is provided: a steel strand unwinding device, including a fixed reel 1, with telescopic mechanisms 2 installed in the middle and on the left and right sides of the fixed reel 1. The telescopic mechanisms 2 are used to adjust the length of the reel. A support mechanism 3 is installed at the bottom of the fixed reel 1. The support mechanism 3 is used to support the fixed reel 1 and the telescopic mechanisms 2.

[0040] The telescopic mechanism 2 includes a rotating shaft 201 that passes through the interior of the fixed scroll 1. Two hydraulic push rods 202 are installed on the middle of the outer side of the fixed scroll 1. Fixed push plates 203 are fixedly connected to the left and right ends of the two hydraulic push rods 202. Movable scrolls 204 are fixedly connected to the outer walls of the two fixed push plates 203. Limiting plates 205 are installed on the left and right sides of the two movable scrolls 204. Fine-tuning components 206 are fixedly connected to the left and right sides of the two movable scrolls 204.

[0041] The fine-tuning component 206 includes two fine-tuning plates 2061, both of which are slidably connected to the outer walls of the left and right ends of the rotating shaft 201. Compression springs 2062 are fixedly connected at equal intervals to the outer walls of the left and right sides of the two fine-tuning plates 2061.

[0042] The fixed push plate 203 and the fine adjustment plate 2061 are slidably connected to the left and right sides of the outer wall of the rotating shaft 201. The limit plate 205 is fixedly connected to the left and right ends of the outer wall of the rotating shaft 201. The mounting column 11 is rotatably connected to the middle of the outer wall of the rotating shaft 201. The two hydraulic push rods 202 are fixedly connected to the left and right outer walls of the mounting column 11.

[0043] Specifically, when the actual working conditions require changing the shaft length of the equipment for steel strands of different diameters, the hydraulic push rod 202 is activated. After the hydraulic push rod 202 starts working, its extension or retraction directly acts on the fixed push plate 203, pushing the fixed push plate 203 to move along the set direction. The fixed push plate 203 is connected to the movable reel 204. When the fixed push plate 203 moves, it drives the movable reel 204 to slide back and forth on the inner wall of the fixed reel 1. During the sliding process, the movable reel 204 ensures the smoothness of the movement through a precise guide structure. As the movable reel 204 slides, the overall length of the two movable reel 204s and the fixed reel 1 changes. During the winding and unwinding of the steel strand, the position of the limit plate 205 remains fixed. During the winding and unwinding of the steel strand, the limit plate 205 can effectively block external forces from interfering with the steel strand and prevent the steel strand from... During the winding and unwinding process, the strand may deviate from the predetermined track and become wound in the wrong position, affecting normal operation. In addition, a fine-tuning component 206 is set between the limit plate 205 and the already wound steel strand. When the steel strand comes into contact with the fine-tuning component 206 during winding and unwinding, it will apply a compressive force to the fine-tuning plate 2061. The fine-tuning plate 2061 is connected to the compression spring 2062. When subjected to compressive force, it will compress the compression spring 2062 to deform it. In this way, after the length of the winding area of ​​the steel strand has been adjusted over a wide range by the relative movement of the fixed reel 1 and the movable reel 204, it can still be adaptively fine-tuned by the fine-tuning component 206. This fine-tuning mechanism can make minor adjustments to the winding position and length of the steel strand according to the actual situation, further improving the adaptability of the equipment under different working conditions and ensuring that the equipment can operate stably and efficiently when handling steel strands of various diameters and lengths.

[0044] Reference Figure 2 , Figure 4 and Figure 5 The support mechanism 3 includes a fixed frame 301, which is installed on the left and right sides of the fixed roller 1. Connecting strips 302 are fixedly connected to the bottom front and rear sides of the fixed frame 301, and reinforcing strips 303 are fixedly connected to the bottom left and right sides of the fixed frame 301. Bearing components 304 are installed on the bottom of the outer walls of the two movable rollers 204.

[0045] The bearing assembly 304 includes a friction wheel 3041, which is engaged with the bottom of the outer wall of the limiting plate 205. Tripods 3042 are installed on both the left and right sides of the friction wheel 3041. Pulleys 3043 are rotatably connected to the front and rear sides of the two tripods 3042. Slide rails 3044 are fixedly connected to the top of the two connecting bars 302. Pulleys 3043 are rotatably connected to the top of the outer wall of the slide rails 3044.

[0046] A rotating shaft 10 is fixedly connected to the middle of the friction wheel 3041. Bearings 9 are rotatably connected to both ends of the rotating shaft 10. Bearings 9 are fixedly connected to the top of the tripod 3042. The friction wheel 3041 is rotatably connected to the top of the tripod 3042 via bearings 9. Multiple anti-slip teeth 6 are fixedly connected to the middle of the outer wall of the friction wheel 3041. Wheel frames 7 are fixedly connected to the front and rear ends of the tripod 3042. A pulley 3043 is rotatably connected to the middle of the wheel frame 7.

[0047] Specifically, the support mechanism 3 provides stable support for the operation of the telescopic mechanism 2. One of its core functions is to change the support position in real time according to the change in the length of the telescopic mechanism 2, ensuring effective support during the telescopic process. The fixed frame 301 fixes the two ends of the hydraulic push rod 202 axially through bolts and other connecting structures, limiting the axial displacement of the hydraulic push rod 202. This prevents the telescopic mechanism 2 from shifting due to the shaking of the hydraulic push rod 202 during rotation, allowing it to rotate stably. The surface of the limiting plate 205 is machined with evenly distributed annular ribs, which mesh with the groove in the middle of the friction wheel 3041, forming a stable transmission relationship. The friction wheel 3041 is mounted on the top of the tripod 3042, which provides stable support. A pulley 3043 is installed at the bottom of the tripod 3042, through which the pulley 3043 moves with the surface of the connecting bar 302. To reduce resistance during movement, when the length of the telescopic mechanism 2 begins to extend or retract, the limiting plate 205 moves synchronously with the movement of the movable scroll 204. Simultaneously, because the friction wheel 3041 is engaged with the limiting plate 205, the friction wheel 3041 moves along with the limiting plate 205 due to this engagement, driving the tripod 3042 to move smoothly on the connecting bar 302 via the pulley 3043 along the preset slide rail 3044, ensuring precise adjustment of the support position. When the fixed scroll 1 and the telescopic mechanism 2 begin to rotate, the limiting plate 205 rotates along with them. During rotation, the limiting plate 205, through engagement, drives the friction wheel 3041 to rotate together on the top of the tripod 3042. This synchronous rotation design avoids relative movement resistance between the two, preventing movement interference and ensuring smooth operation of the entire mechanism.

[0048] Reference Figure 1 and Figure 2A motor bracket 5 is provided at the bottom left side of the fixed roller 1. A drive motor 4 is fixedly connected to the top of the motor bracket 5. The output end of the drive motor 4 is fixedly connected to the left end of the rotating shaft 201. Both the left and right ends of the rotating shaft 201 are rotatably connected to bearings 8. Both bearings 8 are fixedly connected to the top of the fixed frame 301. The rotating shaft 201 is rotatably connected to the top of the fixed frame 301 through the bearings 8.

[0049] Specifically, the drive motor 4 provides power for the rotation of the fixed roller 1 and the telescopic mechanism 2, the motor bracket 5 provides a stable platform for the operation of the drive motor 4, and the bearing 8 enables the rotating shaft 201 and the support mechanism 3 to be rotatably connected, thus connecting the telescopic mechanism 2 and the support mechanism 3.

[0050] Working principle: When it is necessary to change the shaft length of the equipment for steel strands of different diameters, the hydraulic push rod 202 is activated. The extension and retraction of the hydraulic push rod 202 pushes the fixed push plate 203, which in turn drives the movable reel 204 to slide back and forth on the inner wall of the fixed reel 1. This adjusts the overall length of the two movable reel 204 and the fixed reel 1, thus adapting to steel strands of different lengths and diameters. The position of the limit plate 205 is fixed to prevent the steel strand from getting tangled in the wrong position due to external interference during winding and unwinding. In addition, there is a fine-tuning component 206 between the limit plate 205 and the already wound steel strand. When the steel strand contacts the fine-tuning component 206, The fine-tuning plate 2061 is subjected to a squeezing force, and the compression spring 2062 is compressed to compress it. In this way, the length of the winding area of ​​the steel strand can be adjusted over a wide range by the relative movement of the fixed reel 1 and the movable reel 204. It can also be adaptively fine-tuned by the fine-tuning component 206 to improve work adaptability. This mechanism replaces the traditional integrated reel with a modular telescopic reel, which can be adjusted according to actual needs without disassembling and replacing the whole structure. It solves the problems of cumbersome process, low work efficiency, increased labor costs, and hazard to the personal safety of operators and reduced safety in the construction process in the existing technology.

[0051] The support mechanism 3 provides stable support for the operation of the telescopic mechanism 2, mainly by changing its support position according to the change in the length of the telescopic mechanism 2. The fixing bracket 301 fixes the hydraulic push rod 202 axially, thereby enabling the telescopic mechanism 2 to rotate stably. The limiting plate 205 has annular ribs on its surface, which mesh with the groove in the middle of the friction wheel 3041. The friction wheel 3041 is supported by the tripod 3042, which makes contact with the connecting bar 302 through the pulley 3043. When the length of the telescopic mechanism 2 begins to extend or retract... The limiting plate 205 moves along with the movable scroll 204. At the same time, the friction wheel 3041 moves simultaneously due to its engagement with the limiting plate 205, and drives the tripod 3042 to move on the connecting bar 302 and on the slide rail 3044 via the pulley 3043. When the fixed scroll 1 and the telescopic mechanism 2 start to rotate, the limiting plate 205 drives the friction wheel 3041 to rotate together on the top of the tripod 3042 to prevent motion interference. This mechanism can provide dynamic adaptive support for the telescopic mechanism 2 and improve the overall stability of the equipment.

[0052] It should be noted that the above embodiments are only used to illustrate the technical solution of this utility model and are not intended to limit it. Although this utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solution of this utility model without departing from the spirit and scope of the technical solution of this utility model, and all such modifications or substitutions should be covered within the scope of the claims of this utility model.

Claims

1. A steel strand spreading device, characterized in that include: A fixed scroll (1) is provided with telescopic mechanisms (2) installed in the middle and on the left and right sides of the fixed scroll (1). The telescopic mechanisms (2) are used to adjust the length of the scroll. A support mechanism (3) is installed at the bottom of the fixed scroll (1). The support mechanism (3) is used to support the fixed scroll (1) and the telescopic mechanisms (2). The telescopic mechanism (2) includes a rotating shaft (201) that passes through the interior of a fixed scroll (1). Two hydraulic push rods (202) are installed on the middle of the outer side of the fixed scroll (1). Fixed push plates (203) are fixedly connected to the left and right ends of the two hydraulic push rods (202). Movable scrolls (204) are fixedly connected to the outer walls of the two fixed push plates (203). Limiting plates (205) are installed on the left and right sides of the two movable scrolls (204). Fine-tuning components (206) are fixedly connected to the left and right sides of the two movable scrolls (204).

2. A steel strand depositing device according to claim 1, characterized in that: The fine-tuning component (206) includes two fine-tuning plates (2061), both of which are slidably connected to the outer walls of the left and right ends of the rotating shaft (201), and compression springs (2062) are fixedly connected at equal intervals to the outer walls of the left and right sides of the two fine-tuning plates (2061).

3. A steel strand dispensing device according to claim 1, characterized in that: The support mechanism (3) includes a fixed frame (301), which is installed on the left and right sides of the fixed roller (1). Connecting strips (302) are fixedly connected to the front and rear sides of the bottom of the fixed frame (301), and reinforcing strips (303) are fixedly connected to the left and right sides of the bottom of the fixed frame (301). Bearing components (304) are installed on the bottom of the outer walls of the two movable rollers (204).

4. A steel strand depositing device according to claim 3, characterized in that: The bearing assembly (304) includes a friction wheel (3041), which is engaged with the bottom of the outer wall of the limiting plate (205). Tripods (3042) are installed on both the left and right sides of the friction wheel (3041). Pulleys (3043) are rotatably connected to the front and rear sides of the two tripods (3042). Slide rails (3044) are fixedly connected to the top of the two connecting bars (302). The pulleys (3043) are rotatably connected to the top of the outer wall of the slide rails (3044).

5. A steel strand depositing device according to claim 4, characterized in that: The friction wheel (3041) is fixedly connected to the middle of the rotating shaft two (10), and the left and right ends of the rotating shaft two (10) are rotatably connected to the bearing two (9). The bearing two (9) is fixedly connected to the top of the tripod (3042), and the friction wheel (3041) is rotatably connected to the top of the tripod (3042) through the bearing two (9).

6. A steel strand dispensing device according to claim 2, characterized in that: The fixed push plate (203) and the fine adjustment plate (2061) are slidably connected to the left and right sides of the outer wall of the rotating shaft (201), and the limiting plate (205) is fixedly connected to the left and right ends of the outer wall of the rotating shaft (201).

7. A steel strand dispensing device according to claim 4, characterised in that: Multiple anti-slip teeth (6) are fixedly connected to the middle of the outer wall of the friction wheel (3041), and wheel frames (7) are fixedly connected to the front and rear ends of the tripod (3042). The pulley (3043) is rotatably connected to the middle of the wheel frame (7).

8. A steel strand dispensing device according to claim 1, characterized in that: A motor bracket (5) is provided on the bottom left side of the fixed roller (1), and a drive motor (4) is fixedly connected to the top of the motor bracket (5). The output end of the drive motor (4) is fixedly connected to the left end of the rotating shaft (201).

9. A steel strand dispensing device according to claim 3, characterized in that: The left and right ends of the rotating shaft (201) are rotatably connected to bearings (8), and the two bearings (8) are fixedly connected to the top of the fixed frame (301). The rotating shaft (201) is rotatably connected to the top of the fixed frame (301) through the bearings (8).

10. A steel strand dispensing device according to claim 1, characterized in that: The outer wall of the rotating shaft (201) is rotatably connected to the mounting column (11), and the two hydraulic push rods (202) are fixedly connected to the left and right outer walls of the mounting column (11).

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