A curved roof formwork support system
By combining the support frame, lifting adjustment rod, and secondary support plate, the problem of traditional formwork support systems being unable to adapt to the tilt angle of curved roofs is solved, realizing the rapid adjustment and stability of the formwork support system, and improving construction efficiency and stability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- CHINA CONSTR SECOND ENG BUREAU (XIAMEN) CONSTR CO LTD
- Filing Date
- 2025-07-14
- Publication Date
- 2026-06-30
AI Technical Summary
Traditional formwork support systems are difficult to adapt flexibly to the complex and varied tilt angles of curved roofs, resulting in repeated adjustments during formwork support, which reduces installation efficiency and increases construction costs.
The system adopts a combination structure of supporting vertical frame, lifting and adjusting rod, main rib support plate and secondary rib support plate. Through the flexible adjustment function of lifting and adjusting rod and secondary rib support plate, it can adapt to the tilt angle of the bottom wooden secondary rib strip of the template at different positions on the curved roof. Combined with the fixing of limit screws and clamping screws, it can achieve precise adjustment of template support height and angle.
It reduces adjustment time during template installation, improves construction efficiency, and is particularly suitable for the construction of complex curved roof structures such as antique buildings, significantly improving construction efficiency and stability.
Smart Images

Figure CN224431980U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of building construction technology, and in particular, to a curved roof formwork support system. Background Technology
[0002] In architectural engineering, curved roof structures are widely used in large public buildings, cultural venues, and especially in antique-style buildings due to their unique architectural aesthetics and space utilization advantages. However, the construction of curved roof formwork support systems has always been a technical challenge in the construction process. Traditional formwork support systems are mostly designed for flat or conventionally sloped roofs, with fixed support structures. However, the angles of the formwork at different locations on a curved roof vary, making it difficult for traditional formwork support systems to flexibly adapt to the complex and varied tilt angles of curved roofs. This results in repeated adjustments during formwork support, which are cumbersome, reduce installation efficiency, and increase construction costs. Utility Model Content
[0003] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention proposes a curved roof formwork support system.
[0004] To achieve the above objectives, the technical solution adopted by this utility model is as follows:
[0005] A curved roof formwork support system includes: support vertical frames arranged in a left-right direction, with adjacent support vertical frames connected by crossbars; an installation cylinder fixed to the upper end of the support vertical frames; a lifting adjustment rod installed on the upper end of the installation cylinder and capable of adjusting its position relative to the installation cylinder; a main rib support plate installed on the upper end of the lifting adjustment rod, having a support groove with an upper opening and extending through the front and rear; a steel main rib embedded in the support groove; a secondary rib support plate rotatably installed on the steel main rib along a front-rear horizontal axis, the secondary rib support plate having a second side baffle extending upward on its front and rear sides, the second side baffle having nail holes and / or threaded reinforcement holes; and a support adjustment component installed on the main rib support plate and capable of being adjusted up and down relative to the main rib support plate, the upper end of which abuts against the secondary rib support plate to support the secondary rib support plate.
[0006] Furthermore, the mounting cylinder has a first threaded hole at its center, and the lifting adjustment rod is threaded to the first threaded hole so as to achieve lifting adjustment by rotation, and the main support plate can rotate relative to the lifting adjustment rod.
[0007] Furthermore, it also includes a limiting screw. The upper end of the lifting adjustment rod is provided with a second threaded hole. The limiting screw includes a threaded section threaded to the second threaded hole, a cylindrical section provided at the upper end of the threaded section, and a limiting head provided at the upper end of the cylindrical section. The main support plate includes a horizontal plate. The horizontal plate is provided with a circular hole fitted into the cylindrical section. The horizontal plate is located between the limiting head and the upper end of the lifting adjustment rod and can rotate around the cylindrical section.
[0008] Furthermore, the horizontal plate has a countersunk groove on the upper circumferential side of the circular hole for the insertion of the limiting head.
[0009] Furthermore, the main support plate includes a horizontal plate and side plates disposed on the left and right sides of the horizontal plate, the horizontal plate and the side plates defining a support groove.
[0010] Furthermore, both sides of the side plates are threaded with clamping screws, which are used to clamp the main steel ribs.
[0011] Furthermore, the side plate is provided with a through hole, and a nut aligned with the through hole is fixed on the side plate. The clamping screw passes through the through hole and is threadedly connected to the nut.
[0012] Furthermore, one of the side plates is provided with a horizontally extending transverse plate, and the support adjustment member is a vertical screw threaded to the transverse plate.
[0013] Furthermore, the upper end of the main steel rib is provided with a hinge seat, and the bottom of the secondary rib support plate is provided with a hinge part. The hinge part and the hinge seat are provided with corresponding holes for connection through a hinge shaft.
[0014] Furthermore, the support frame includes multiple vertically spliced support rods, the upper end of each support rod is provided with a connecting expansion tube, the bottom of the upper support rod is inserted into the adjacent connecting expansion tube below, and the mounting cylinder is inserted into the connecting expansion tube of the uppermost support rod.
[0015] This utility model has the following beneficial effects:
[0016] The adjustable height of the formwork support is flexibly adjusted through the cooperation of the lifting rod and the mounting cylinder. Simultaneously, the secondary rib support plate can rotate along the front and rear horizontal axes, accommodating the varying inclination angles of the wooden secondary ribs at the bottom of the formwork at different locations on a curved roof. Combined with the second side baffle and nail holes or threaded reinforcement holes, the wooden secondary ribs attached to the secondary rib support plate can be reinforced. The flexible adjustment function of the lifting rod and the secondary rib support plate reduces adjustment time during formwork installation. The rotation of the secondary rib support plate, combined with the rapid height adjustment of the support components to accommodate the wooden secondary ribs at the bottom of the formwork at different locations, allows the formwork support system to quickly adapt to changes in the inclination angle of the wooden secondary ribs at the bottom of the formwork on a curved roof. The adjustment is simple, requiring no repeated adjustments, significantly improving construction efficiency, and is particularly suitable for the construction of complex curved roof structures such as antique-style buildings.
[0017] In addition to the objectives, features, and advantages described above, this utility model has other objectives, features, and advantages. The present utility model will now be described in further detail with reference to the figures. Attached Figure Description
[0018] The accompanying drawings, which form part of this application, are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an undue limitation of the present invention. In the drawings:
[0019] Figure 1 This is a structural schematic diagram of the utility model in its practical application state;
[0020] Figure 2 This is a partial structural schematic diagram of an embodiment of the present utility model;
[0021] Figure 3 This is an exploded structural diagram of a portion of the present invention;
[0022] Figure 4 This is a partial cross-sectional view of an embodiment of the present utility model;
[0023] Figure 5 yes Figure 4 Enlarged view of point A;
[0024] Figure 6 This is a partial schematic diagram of the connection structure between the crossbar and the support bar.
[0025] Legend:
[0026] Supporting vertical frame 100, horizontal bar 110, connecting clamping plate 111, clamping plate 112, support rod 120, and connecting expansion pipe 130;
[0027] Mounting cylinder 200, first threaded hole 210;
[0028] Lifting adjustment rod 300, second threaded hole 310;
[0029] Main support plate 400, support groove 410, horizontal plate 420, round hole 430, countersunk groove 440, side plate 450, through hole 451, clamping screw 460, nut 470, transverse plate 480.
[0030] 500 steel main ribs, 510 hinged joints;
[0031] Secondary support plate 600, second side baffle 610, nail hole 620, threaded reinforcement hole 630, hinge part 640;
[0032] Support adjustment component 700;
[0033] Limit screw 800, threaded section 810, cylindrical section 820, limit head 830;
[0034] 900 timber joists, 910 timber formwork, 920 timber strips. Detailed Implementation
[0035] It should be understood that the specific embodiments described herein are merely illustrative of the present invention and are not intended to limit the present invention.
[0036] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0037] It should be noted that all directional indicators (such as up, down, left, right, front, back, etc.) in this utility model embodiment are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicator will also change accordingly.
[0038] Furthermore, the use of terms such as "first" and "second" in this utility model is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. When the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed by this utility model.
[0039] Please refer to Figure 1 and Figure 2 A preferred embodiment of the curved roof formwork support system provided by this utility model includes a support frame 100, an installation cylinder 200, a lifting adjustment rod 300, a main rib support plate 400, a steel main rib 500, a secondary rib support plate 600, and a support adjustment component 700.
[0040] The supporting vertical frames 100 are arranged in a left-right direction, and adjacent supporting vertical frames 100 are connected by horizontal bars 110. Specifically, as shown... Figure 6 As shown, a connecting clamp 111 is provided at the end of the crossbar 110. The connecting clamp 111 and the clamping plate 112 are connected and fixed by fasteners, thereby holding the support frame 100 tightly.
[0041] Typically, two secondary wooden joists 900 are installed at the bottom of a wooden formwork 910, one at the front and one at the back. Therefore, there are usually two sets of supporting vertical frames 100 arranged at the front and back to support the two secondary wooden joists 900. Adjacent supporting vertical frames 100 on the left and right support the same secondary wooden joist 900. Figure 1As shown, a wooden strip 920 is embedded between the secondary wooden joists 900 and the curved wooden template 910 to prevent the edges of the curved wooden template 910 from floating. The secondary wooden joists 900, the wooden template 910, and the wooden strip 920 can all be connected and fixed with nails.
[0042] The mounting cylinder 200 is fixed to the upper end of the support frame 100.
[0043] The lifting adjustment rod 300 is installed on the upper end of the mounting cylinder 200 and can be raised and lowered relative to the mounting cylinder 200 to adjust its position.
[0044] The main support plate 400 is installed on the upper end of the lifting adjustment rod 300. The main support plate 400 has a support groove 410 that is open at the top and runs through the front and back.
[0045] The main steel rib 500 is embedded in the support groove 410. The main rib support plate 400 cooperates with the main steel rib 500 through the support groove 410 to provide a stable support foundation for the formwork.
[0046] The secondary joist support plate 600 is rotatably mounted on the main steel joist 500 along its front and rear horizontal axes. The secondary joist support plate has upwardly extending second side baffles 610 on its front and rear sides. The second side baffles 610 have nail holes 620 and / or threaded reinforcement holes 630. Nails can be inserted into the nail holes 620 to reinforce the secondary joist 900. The threaded reinforcement holes 630 are threaded holes, and set screws can be threaded into them. By tightening the set screws, the secondary joist 900 is pressed firmly. In this embodiment, both nail holes 620 and threaded reinforcement holes 630 are present, and either nails or set screws can be selected as needed. Of course, if the secondary joist 900 has a large tilt angle, both nails and set screws can be used simultaneously. In other embodiments, only nail holes 620 or threaded reinforcement holes 630 may be provided.
[0047] When the tilt angle of the secondary joist 900 is large, making the tilt support unstable, a nail can be inserted into the nail hole 620 to improve stability, and the nail will be driven into the secondary joist 900.
[0048] Of course, for construction safety, the 900mm timber joists can be reinforced with nails at any angle of inclination.
[0049] The support adjustment component 700 is installed on the main joist support plate 400 and can be raised and lowered relative to the main joist support plate 400. The upper end of the support adjustment component 700 abuts against the secondary joist support plate 600 to support the secondary joist support plate 600. Thus, the support of the secondary joist support plate 600 at different tilt angles can be achieved by raising and lowering the support adjustment component 700.
[0050] In existing technologies, wooden wedges are inserted between the main joist support plate 400 and the secondary joist strip 900, and the wedges are connected and fixed to the secondary joist strip 900 with nails to achieve stable support of the secondary joist strip 900 by the main joist support plate 400. However, this method makes the tilt angle of the secondary joist strip 900 non-adjustable, and adjustment may require replacing wooden wedges of different specifications or embedding additional wooden wedges, making adjustment cumbersome and potentially requiring multiple adjustments. The curved roof formwork support system provided by this utility model, through the cooperation of the lifting adjustment rod 300 and the installation cylinder 200, achieves flexible adjustment of the formwork support height. Simultaneously, the secondary joist support plate 600 can rotate along the front and rear horizontal axes, adapting to the tilt angle of the secondary joist strip 900 at the bottom of the formwork 910 at different positions on the curved roof. The flexible adjustment function of the lifting adjustment rod 300 and the secondary joist support plate 600 reduces the adjustment time during formwork installation. The rotation of the secondary rib support plate 600, combined with the quick-lifting and angle-adjustable support adjustment component 700, adapts to the different positions of the wooden secondary ribs 900 at the bottom of the template. This allows the template support system to quickly adapt to changes in the tilt angle of the wooden secondary ribs 900 at the bottom of the template on the curved roof. The adjustment is simple and does not require repeated adjustments, significantly improving construction efficiency. It is especially suitable for the construction of complex curved roof structures such as antique buildings.
[0051] Understandably, due to the inclined angle of the wooden secondary rib 900, the heights of the main rib support plate 400, steel main rib 500, and secondary rib support plate 600 on the adjacent left and right support uprights 100 are different. This difference can be achieved by adjusting the lifting and lowering of the lifting adjustment rod 300. If the height difference is too large, the height difference can also be widened by using mounting cylinders 200 of different lengths, so that the height difference of the adjacent left and right secondary rib support plates 600 meets the requirements.
[0052] Reference Figure 2 and Figure 3 In some embodiments of this utility model, the mounting cylinder 200 has a first threaded hole 210 at its center, and the lifting adjustment rod 300 is threadedly connected to the first threaded hole 210 to achieve lifting adjustment by rotation. The main support plate 400 can rotate relative to the lifting adjustment rod 300. The threaded connection between the first threaded hole 210 at the center of the mounting cylinder 200 and the lifting adjustment rod 300 allows for precise adjustment of the support height of the template 910 by rotating the lifting adjustment rod 300, meeting the need for fine-tuning the height during construction and further improving the adaptability and flexibility of the system. The main support plate 400 can rotate relative to the lifting adjustment rod 300, so that the main support plate 400 does not rotate with the lifting adjustment rod 300 when the lifting adjustment rod 300 rotates, thus being unaffected by the rotation of the lifting adjustment rod 300.
[0053] Reference Figure 3 , Figure 4 and Figure 5 In some embodiments of this utility model, a limiting screw 800 is also included. The upper end of the lifting adjustment rod 300 is provided with a second threaded hole 310. The limiting screw 800 includes a threaded section 810, a cylindrical section 820, and a limiting head 830. The threaded section 810 is threadedly connected to the second threaded hole 310. The cylindrical section 820 is located at the upper end of the threaded section 810, and the limiting head 830 is located at the upper end of the cylindrical section 820. The diameters of the threaded section 810, the cylindrical section 820, and the limiting head 830 increase sequentially. The diameter of the cylindrical section 820 is adapted to the diameter of the circular hole 430, typically with a clearance fit. The main support plate 400 includes a horizontal plate 420. The horizontal plate 420 is provided with a circular hole 430 fitted into the cylindrical section 820. The horizontal plate 420 is located between the limiting head 830 and the upper end of the lifting adjustment rod 300 and can rotate around the cylindrical section 820. The cylindrical section 820 and the limiting head 830 allow the main rib support plate 400 to be stably fitted onto the cylindrical section 820, and to rotate between the limiting head 830 and the upper end of the lifting adjustment rod 300. The limiting head 830 does not press against the main rib support plate 400, but only serves as a vertical limit, restricting the vertical axial movement of the main rib support plate 400 while ensuring its rotational freedom, effectively avoiding the problem of unstable support caused by excessive rotation or loosening.
[0054] Reference Figure 3 , Figure 4 and Figure 5 In some embodiments of this utility model, the horizontal plate 420 has a countersunk groove 440 on the upper circumferential side of the circular hole 430 for the insertion of the limiting head 830. The countersunk groove 440 on the upper circumferential side of the circular hole 430 of the horizontal plate 420 allows the limiting head 830 of the limiting screw 800 to be better inserted therein, thereby preventing the limiting head 830 from protruding from the upper surface of the horizontal plate 420 and contacting the main steel rib 500, which would lead to unstable support.
[0055] Reference Figure 3 , Figure 4 and Figure 5 In some embodiments of this utility model, the main rib support plate 400 includes a horizontal plate 420 and side plates 450 disposed on the left and right sides of the horizontal plate 420. The horizontal plate 420 and the side plates 450 define a support groove 410. The main rib support plate 400, composed of the horizontal plate 420 and the left and right side plates 450, forms a support groove 410 that is open at the top and extends through the front and back, which can stably support the steel main rib 500 and provide a reliable support foundation for the formwork. By limiting the steel main rib 500 through the side plates 450, the stability of the formwork support system is further improved. Furthermore, it makes the installation of the steel main rib 500 simpler and faster. Construction workers can quickly embed the steel main rib 500 into the support groove 410 without having to hold the steel main rib 500 in place to prevent it from falling during installation, thus reducing installation time and labor intensity and improving construction efficiency.
[0056] Reference Figure 3 , Figure 4 and Figure 5 In some embodiments of this utility model, both side plates 450 are threadedly connected with clamping screws 460, which are used to clamp the main steel ribs 500. Through the clamping action of the clamping screws 460, the main steel ribs 500 can be firmly fixed within the support grooves 410 of the main rib support plate 400, effectively preventing the main steel ribs 500 from loosening or shifting due to external forces during construction, thereby further enhancing the overall stability of the formwork support system and ensuring construction quality. Furthermore, the clamping screws 460 allow the main rib support plate 400 to adapt to main steel ribs 500 of different sizes, and also allow adjustment of the left-right fixing position of the main rib support plate 400, improving the versatility and flexibility of the formwork support system and reducing construction costs.
[0057] Reference Figure 3 , Figure 4 and Figure 5 In some embodiments of this utility model, the side plate 450 is provided with a through hole 451, and a nut 470 aligned with the through hole 451 is fixed on the side plate 450. A clamping screw 460 passes through the through hole 451 and is threadedly connected to the nut 470, thereby facilitating the threaded connection of the clamping screw 460 and making it easy to process. The nut 470 can be fixed to the side plate 450 by welding.
[0058] Reference Figure 3 , Figure 4 and Figure 5 In some embodiments of this utility model, one side plate 450 is provided with a horizontally extending transverse plate 480, and the support adjustment member 700 is a vertical screw threadedly connected to the transverse plate 480. The transverse plate 480 has a through hole and a connecting nut welded to it, and the vertical screw is threadedly connected to the connecting nut. This allows the support adjustment member 700 to be flexibly adjusted in height, thereby quickly adapting to changes in the angle of the secondary support plate 600. Construction personnel can quickly adjust it to the required position, reducing construction time and labor intensity, and improving construction efficiency.
[0059] Reference Figure 3 , Figure 4 and Figure 5 In a further embodiment of this utility model, the upper end of the main steel rib 500 is provided with a hinge seat 510, and the bottom of the secondary rib support plate 600 is provided with a hinge part 640. The hinge part 640 and the hinge seat 510 are provided with corresponding holes for connection through a hinge shaft. This allows the secondary rib support plate 600 to rotate flexibly along the front and rear horizontal axes, and can quickly adapt to the tilt angle of the wooden secondary rib 900 at the bottom of the template at different positions on the curved roof, without the need for complicated adjustment operations.
[0060] Reference Figure 1 , Figure 3 In a further embodiment of this utility model, the support frame 100 includes multiple vertically spliced support rods 120. The upper end of each support rod 120 is provided with a connecting expansion tube 130. The bottom of the upper support rod 120 is inserted into the adjacent lower connecting expansion tube 130. The connecting expansion tube 130 and the bottom of the support rod 120 are provided with holes so that adjacent support rods 120 can be fixed by fasteners when spliced. The mounting cylinder 200 is inserted into the connecting expansion tube 130 of the uppermost support rod 120. This achieves the positioning and installation of the mounting cylinder 200. It is understood that the mounting cylinder 200 is provided with holes to align with the holes of the connecting expansion tube 130 of the uppermost support rod 120 and is fixed by fasteners, which can be bolts and nuts.
[0061] The above are merely preferred embodiments of this utility model and are not intended to limit the scope of this utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this utility model should be included within the protection scope of this utility model.
Claims
1. A curved roof formwork support system characterised in that, include: Supporting vertical frames (100) are arranged in the left-right direction, and adjacent supporting vertical frames (100) are connected by horizontal bars (110); The mounting sleeve (200) is fixed to the upper end of the support frame (100); The lifting adjustment rod (300) is installed on the upper end of the mounting cylinder (200) and can be adjusted in position relative to the mounting cylinder (200); The main support plate (400) is installed on the upper end of the lifting adjustment rod (300) and has a support groove (410) that is open at the top and runs through the front and back. The main steel rib (500) is embedded in the support groove (410); A secondary rib support plate (600) is rotatably installed on the main steel rib (500) along the front and rear horizontal axis. The secondary rib support plate is provided with an upwardly extending second side baffle (610) on the front and rear sides. The second side baffle (610) is provided with nail holes (620) and / or threaded reinforcement holes (630). The support adjustment component (700) is installed on the main joist support plate (400) and can be raised and lowered relative to the main joist support plate (400). Its upper end abuts against the secondary joist support plate (600) to support the secondary joist support plate (600).
2. The curved roof formwork support system according to claim 1, wherein, The mounting cylinder (200) has a first threaded hole (210) at its center. The lifting adjustment rod (300) is threaded to the first threaded hole (210) so as to achieve lifting adjustment by rotation. The main support plate (400) can rotate relative to the lifting adjustment rod (300).
3. The curved roof formwork support system according to claim 1, characterized in that, It also includes a limiting screw (800), the upper end of the lifting adjustment rod (300) is provided with a second threaded hole (310), the limiting screw (800) includes a threaded section (810) threaded to the second threaded hole (310), a cylindrical section (820) provided at the upper end of the threaded section (810) and a limiting head (830) provided at the upper end of the cylindrical section (820), the main support plate (400) includes a horizontal plate (420), the horizontal plate (420) is provided with a circular hole (430) sleeved on the cylindrical section (820), the horizontal plate (420) is located between the limiting head (830) and the upper end of the lifting adjustment rod (300), and can rotate around the cylindrical section (820).
4. The curved roof formwork support system according to claim 3, characterized in that, The horizontal plate (420) has a countersunk groove (440) on the upper circumference of the circular hole (430) for the insertion of the limiting head (830).
5. The curved roof formwork support system according to claim 1, characterized in that, The main support plate (400) includes a horizontal plate (420) and side plates (450) disposed on the left and right sides of the horizontal plate (420), wherein the horizontal plate (420) and the side plates (450) define a support groove (410).
6. The curved roof formwork support system according to claim 5, characterized in that, Both sides of the side plates (450) are threaded with clamping screws (460), which are used to clamp the main steel ribs (500).
7. The curved roof formwork support system according to claim 6, characterized in that, The side plate (450) is provided with a through hole (451), and a nut (470) aligned with the through hole (451) is fixed on the side plate (450). The clamping screw (460) passes through the through hole (451) and is threadedly connected to the nut (470).
8. The curved roof formwork support system according to claim 5, characterized in that, One of the side plates (450) is provided with a horizontal plate (480) extending outward, and the support adjustment member (700) is a vertical screw threaded to the horizontal plate (480).
9. The curved roof formwork support system according to claim 1, characterized in that, The upper end of the main steel rib (500) is provided with a hinge seat (510), and the bottom of the secondary rib support plate (600) is provided with a hinge part (640). The hinge part (640) and the hinge seat (510) are provided with corresponding holes for connection through a hinge shaft.
10. The curved roof formwork support system according to claim 1, characterized in that, The support frame (100) includes multiple vertically spliced support rods (120). The upper end of the support rod (120) is provided with a docking expansion tube (130). The bottom of the upper support rod (120) is inserted into the adjacent docking expansion tube (130) below. The mounting cylinder (200) is inserted into the docking expansion tube (130) of the uppermost support rod (120).