A stackable pad, load bearing assembly

Abstract

The application discloses a stackable cushion block, which comprises a cushion block body, a buckle part and a avoiding part are arranged on the cushion block body, when the cushion block body is used alone, the buckle part is used for detachable connection with external components, when two same cushion block bodies are stacked up and down, the two cushion block bodies are in a first relative position after being relatively rotated by 180 degrees, at this time, the buckle part of the lower cushion block body is converted into cooperation with the avoiding part of the upper cushion block body, and the upper and lower stacking is fixed. The application improves the structure of the cushion block, first, the cushion block is stacked by self-rotation to increase the height, and no additional materials are needed; second, the endless position adjustment of the bottom beam is realized through the spring sheet self-locking mechanism in the middle of the cushion block, and the bottom beam does not need to be holed; third, the cushion block and the bottom beam are flexible to install, and the endless adjustment installation is realized.

Description

Technical Field

[0001] This invention relates to the field of rooftop photovoltaic support installation technology, specifically to a stackable pad and load-bearing assembly. Background Technology

[0002] In technical fields involving the support and installation of base beams, such as solar photovoltaic support systems and equipment mounting bases, it is common practice to install pads under the base beams to provide support, leveling, or isolation. A reliable fixed connection is required between the pads and the base beams, and the pads must also be able to be flexibly stacked when height needs to be increased.

[0003] As attached Figure 1-4 As shown, one existing installation method on the market is as follows: The existing pad 300 has an inverted buckle 301 and a raised limiting block 302. The left and right sides of the existing base beam 400 are fixed to the pad 300 via the inverted buckle. To prevent the base beam 400 from moving in the front-to-back direction, a rectangular hole 401 is pre-drilled on the base beam 400. The raised limiting block 302 on the existing pad 300 is inserted into this rectangular hole 401 to achieve front-to-back limiting and fixing. This method has the following problems in actual use:

[0004] First, the installation is not flexible enough. Because the limiting block can only be inserted into the preset rectangular hole, the installation position of the bottom beam relative to the pad block is limited by the opening position of the rectangular hole, and it cannot be infinitely adjusted according to the actual site conditions. When there are deviations in the installation environment or when fine adjustments are required, the existing fixed position cannot meet the needs.

[0005] Secondly, additional materials are required when increasing the height. The height of the pads is fixed. When the height needs to be increased on site, additional materials and components must be used for padding. This not only increases the variety of materials and inventory costs, but also causes inconvenience to on-site construction.

[0006] Third, the bottom beam has high processing costs. In order to achieve front and rear limiting, rectangular holes need to be pre-drilled on the bottom beam. This additional processing step not only increases processing time but also manufacturing costs.

[0007] Therefore, it is necessary to improve the existing pad structure to solve the above-mentioned technical problems. Summary of the Invention

[0008] To address the aforementioned shortcomings of existing pad technology, this invention provides a stackable pad and load-bearing assembly. The structure of the pad is improved in three ways: first, the height is increased by rotating and stacking the pad itself, without the need for additional materials; second, the bottom beam can be infinitely adjusted in position through a spring-loaded self-locking mechanism in the middle of the pad, without the need for holes in the bottom beam; and third, the pad and bottom beam are flexibly installed, enabling infinitely adjustable installation.

[0009] To achieve the above objectives, the present invention provides the following technical solution: a stackable pad, comprising a pad body; the pad body is provided with a snap-fit ​​part and a clearance part; when the pad body is used alone, the snap-fit ​​part is used to detachably connect with an external component; when two identical pad bodies are stacked one on top of the other, the two pad bodies are in a first relative position after being rotated 180 degrees relative to each other, at which time the snap-fit ​​part of the lower pad body is converted to cooperate with the clearance part of the upper pad body to achieve vertical stacking and fixation.

[0010] Furthermore, the pad body has four corner regions, each corner region is provided with a set of connecting units, each set of connecting units includes a latching part and a clearance part, and the latching part and the clearance part are distributed left and right in the corner region.

[0011] Furthermore, in the four corner regions, the two sets of connecting units located diagonally have their latching parts and clearance parts distributed in the same left and right positions, so that after the pad is rotated 180 degrees, the latching parts and clearance parts of the upper and lower pad bodies are directly opposite each other in the vertical direction.

[0012] Furthermore, a spring self-locking mechanism is provided in the middle of the pad body, and the top of the spring self-locking mechanism is higher than the upper surface of the pad body; when installed with the first external component, the bottom surface of the first external component presses the spring self-locking mechanism, causing the spring self-locking mechanism to undergo elastic deformation, and the rebound force of the spring self-locking mechanism forms a self-lock on the first external component.

[0013] Furthermore, the spring self-locking mechanism consists of a left spring and a right spring; both the left and right springs extend obliquely upwards from bottom to top, and their tops are higher than the upper surface of the pad body; when installed with the first external component, the bottom surface of the first external component presses against the left and right springs, causing the left spring to undergo clockwise elastic deformation and the right spring to undergo counterclockwise elastic deformation, and the rebound force of the two springs forms a self-locking mechanism on the first external component in the left-right direction.

[0014] Furthermore, the pad body includes a base plate and intersecting reinforcing ribs extending upward from the upper surface of the base plate, the upper surface of the reinforcing ribs forming the upper surface of the pad body; the snap-fit ​​portion and the clearance portion are arranged within the grid formed by the reinforcing ribs.

[0015] Furthermore, the latching part is an inverted latch, and the clearance part is a clearance groove.

[0016] On the other hand, a load-bearing assembly includes an outer member and at least one of the stackable pads; the outer member is a bottom beam with its two side edges connected to the topmost pad via snap-fit ​​connections.

[0017] Furthermore, the number of pads is one, and the two sides of the bottom beam are connected to the pads by inverted snap fasteners; the bottom surface of the bottom beam is pressed against the spring self-locking mechanism of the pads, and the rebound force generated by the deformation of the left and right springs forms a friction self-locking in the left and right directions, so that the bottom beam can be infinitely positioned at any position in the front and back directions.

[0018] Furthermore, the number of pads is at least two. Any two adjacent pads can be rotated 180 degrees relative to each other so that the inverted part of the lower pad is inserted into the clearance groove of the upper pad to form a snap-fit, thereby achieving stacking and fixing.

[0019] The stackable pad of the present invention has the following beneficial effects:

[0020] 1. When used alone, the same overlock of the pad serves as a connector to external components. When stacked, it functions to cooperate with the clearance part of the upper pad, thus achieving structural reuse. The pad retains its original connecting function and can be stacked directly to increase its height without the need for additional materials. It is very flexible in use, and during on-site installation, the height can be increased at any time according to actual needs without having to prepare pads of different specifications in advance.

[0021] 2. The pad body has four corner areas, located at the upper left, lower left, upper right, and lower right respectively. In the four corner areas, the two sets of connecting units located diagonally have the same left and right distribution of the snap-fit ​​and clearance parts. This symmetrical layout does not require additional alignment or adjustment. Simply rotate the pad 180 degrees, and the snap-fit ​​and clearance groove of the upper and lower pads will automatically align. The installation is very convenient and quick, and it is suitable for on-site operation.

[0022] 3. The design of the spring self-locking mechanism eliminates the need for rectangular limiting holes in the front and rear directions of the bottom beam, simplifying its processing and significantly reducing manufacturing costs. The two springs can provide stable self-locking force at any position on the bottom surface of the bottom beam, allowing the bottom beam to be installed at any position in the front and rear directions, achieving stepless adjustment and greatly improving installation flexibility. The self-locking is naturally formed by the elastic rebound force of the springs, eliminating the need for additional bolts, pins, or other locking components. The installation process can be completed simply by pressing, making operation convenient.

[0023] The bearing assembly of the present invention has the following beneficial effects:

[0024] 4. The system has a simple composition, requiring only a base beam and pads of the same specification. There is no need to prepare pads of different heights or additional height-increasing accessories, which reduces the types of materials and inventory costs.

[0025] 5. Flexible on-site installation: Construction personnel can decide whether to increase the height and how many layers to increase it based on the actual terrain and usage requirements, making it highly adaptable.

[0026] 6. The entire installation process of the load-bearing assembly is mainly done by pressing, requiring no special tools and resulting in high construction efficiency. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the existing pad block and existing bottom beam in the prior art.

[0028] Figure 2 This is a schematic diagram of the assembly of existing pads and existing bottom beams in the prior art.

[0029] Figure 3 This is a side view of the assembly of the existing pad blocks and existing bottom beams.

[0030] Figure 4 for Figure 3 Sectional view along the middle AA.

[0031] Figure 5 This is a schematic diagram of the structure of the pad block and the bottom beam in this invention.

[0032] Figure 6 This is a partial cross-sectional view of the assembly of the pad block and the bottom beam in this invention.

[0033] Figure 7 This is a partial cross-sectional view of the two pad blocks assembled in this invention.

[0034] Figure 8 This is a top view of the pad block in this invention.

[0035] Figure 9 This is a schematic diagram of the structure of the two pads in the first relative position in this invention.

[0036] Figure 10 This is a schematic diagram of the structure when the two pads are in the second relative position in this invention.

[0037] Figure 11 This is a diagram showing the state changes of the spring self-locking mechanism in this invention.

[0038] Figure 12 This is a diagram showing the assembly steps of a load-bearing assembly according to the present invention.

[0039] Figures 1-4 Reference numerals in the prior art: prior art pad 300, undercut 301, protruding limiting block 302, prior art bottom beam 400, rectangular hole 401.

[0040] Figures 5-12Reference numerals in the drawings of the present invention: pad 100, upper pad 100a, lower pad 100b, pad body 1, base plate 11, reinforcing rib plate 12, snap fastener 2, buckle 21, hook 211, clearance part 3, clearance groove 31, spring self-locking mechanism 4, left spring 41, right spring 42, external component 200, protrusion 201. Detailed Implementation

[0041] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments. It should be understood that the specific embodiments described herein are for illustrative purposes only and do not constitute a limitation thereof.

[0042] This invention provides a stackable pad 100, mainly used in applications requiring support and installation of base beams, such as solar photovoltaic support systems and equipment mounting bases. The core improvements of this invention lie in two aspects: first, the height is increased through the rotational stacking of the pad 100 itself, eliminating the need for additional materials; second, the spring-loaded self-locking mechanism 4 enables stepless position adjustment of the external component 200 (base beam), eliminating the need for openings in the external component 200.

[0043] As attached Figure 9 As shown, this invention defines the first relative orientation of the upper pad 100a after rotating 180 degrees relative to the lower pad 100b, as illustrated in the attached figure. Figure 10 As shown, the second relative orientation is the original state in which the upper pad 100a does not rotate relative to the lower pad 100b.

[0044] Please see the appendix Figure 5-12 As shown, the following explanation uses a specific pad block 100 structure as an example:

[0045] The pad 100 includes a pad body 1; the pad body 1 is provided with a snap-fit ​​part 2 and a clearance part 3; when the pad body 1 is used alone, the snap-fit ​​part 2 is used to connect detachably with the external component 200 (bottom beam); when two identical pad bodies 1 are stacked one on top of the other, the two pad bodies 1 are in the first relative position after rotating 180 degrees relative to each other. At this time, the snap-fit ​​part 2 of the lower pad body 1 is converted to cooperate with the clearance part 3 of the upper pad body 1 to achieve the vertical stacking and fixing.

[0046] The buckle 2 is specifically an inverted buckle 21 extending upward from the upper surface of the base plate 11, and the top of the inverted buckle 21 has an inwardly bent hook 211; the clearance part 3 is specifically a clearance groove 31 opened on the base plate 11, and the shape and size of the clearance groove 31 are adapted to the hook 211 of the inverted buckle, so that the inverted buckle 21 can pass into the clearance groove 31 from below and hook the edge of the clearance groove 31.

[0047] The pad body 1 has two usage states. The first is the standalone usage state, as shown in the attached figure. Figure 6 As shown, when only one pad 100 is needed, the buckles on the pad body 1 are directly connected to the external component 200. The external component 200 is typically a bottom beam, with its two edges respectively engaging the buckles on both sides of the pad 100 for fixation. The second configuration is a stacked configuration, as shown in the attached diagram. Figure 7 As shown, when height needs to be increased, two identical pad blocks 1 are stacked vertically. Before stacking, the upper pad block 100a or the lower pad block 100b is rotated 180 degrees, at which point the two pad blocks 100 are in a first relative position. In this position, the buckle 21 of the lower pad block 100b is vertically aligned with the clearance groove 31 of the upper pad block 100a. The buckle of the lower pad block 100b is inserted into the clearance groove 31 of the upper pad block 100a, and the hook 211 of the buckle 21 hooks the edge of the clearance groove 31, thereby achieving a fixed vertical connection between the two pad blocks 100. In this way, the same buckle 21, when used alone, serves to connect the external component 200, and when used in a stacked configuration, it transforms into a function that cooperates with the clearance part 3 of the upper pad block 100a, thus achieving structural reuse. The advantages of this structure are that the pad 100 retains the original connection function and can be stacked directly to increase the height without the need for additional materials. It is very flexible in use, and the height can be increased at any time according to actual needs during on-site installation, without having to prepare pads 100 of different specifications in advance.

[0048] To ensure accurate alignment of the inverted buckles 21 and the clearance grooves 31 of the upper and lower pads 100 during stacking, the layout of the inverted buckles and clearance grooves in this invention has been carefully designed. Specifically, as shown in the attached... Figure 8As shown, the pad body 1 has four corner areas, located at the upper left, lower left, upper right, and lower right positions respectively. Each corner area has a set of connecting units, each set of connecting units including a snap-fit ​​part 2 and a clearance part 3, with the snap-fit ​​part 2 and clearance part 3 distributed left and right within the corner area. The key design is that in the four corner areas, the snap-fit ​​part 2 (inverted snap) and clearance part 3 (clearance groove) of the two sets of connecting units located diagonally are positioned in the same left and right directions, so that after the pad 100 is rotated 180 degrees, the snap-fit ​​part 2 and clearance part 3 of the upper and lower pad bodies 1 are vertically aligned. For example, in the upper left corner area, the clearance groove 31 is located on the left and the snap-fit ​​21 is located on the right; in the lower right corner area (diagonally opposite to the upper left corner), the clearance groove 31 is located on the left and the snap-fit ​​21 is located on the right. Similarly, in the upper right corner area, the inverted buckle 21 is located on the left and the clearance groove 31 is on the right; in the lower left corner area, the inverted buckle 21 is located on the left and the clearance groove 31 is on the right. With this arrangement, when a lower pad 100b is rotated 180 degrees, the original left clearance groove 31 in the upper left corner area will rotate to the right side of the lower right corner area, and the right side of the lower right corner of the upper pad 100a will be precisely where the inverted buckle 21 is located. The two are vertically aligned, allowing the inverted buckle 21 to smoothly insert into the clearance groove 31. The same applies to other corner areas. The advantage of this symmetrical layout is that no additional alignment or adjustment is required; simply rotating the pad 100 by 180 degrees automatically aligns the inverted buckles and clearance grooves of the upper and lower pads 100, making installation very convenient and quick, suitable for on-site operation.

[0049] As attached Figure 5 and 11As shown, a spring-loaded self-locking mechanism 4 is provided in the middle of the pad body 1. The top of the spring-loaded self-locking mechanism 4 is higher than the upper surface of the pad body 1. When installed with the first external component 200, the bottom surface of the first external component 200 presses against the spring-loaded self-locking mechanism 4, causing the spring-loaded self-locking mechanism 4 to undergo elastic deformation. The rebound force of the spring-loaded self-locking mechanism 4 forms a self-locking on the first external component 200. Specifically, the spring-loaded self-locking mechanism 4 consists of a left spring 41 and a right spring 42. The left spring 41 and the right spring 42 both extend inclined towards each other from bottom to top, that is, the left spring 41 is inclined to the upper right and the right spring 42 is inclined to the upper left, and the two are distributed in a figure-eight shape. The tips of both the left spring piece 41 and the right spring piece 42 protrude above the upper surface of the pad body 1. When installed with the first external component 200, the bottom surface of the first external component 200 presses against the left spring piece 41 and the right spring piece 42, causing the left spring piece 41 to undergo clockwise elastic deformation and the right spring piece 42 to undergo counterclockwise elastic deformation. The rebound force of the two spring pieces forms a self-locking mechanism against the first external component 200 in the left-right direction. In the actual installation process, when the bottom beam is pressed into the buckle of the pad 100, the bottom surface of the bottom beam moves downward and first contacts the tips of the spring pieces. As the bottom beam continues to press down, the bottom surface of the bottom beam simultaneously presses against the left spring piece 41 and the right spring piece 42, forcing the left spring piece 41 to undergo clockwise elastic deformation and the right spring piece 42 to undergo counterclockwise elastic deformation. Due to the spring pieces' tendency to rebound, the two spring pieces will continue to expand outward and form a tight contact with the bottom surface of the bottom beam, thereby forming a frictional self-locking mechanism against the bottom beam in the left-right direction. Preferably, the spring self-locking mechanism 4 can be made of plastic or metal and integrally formed with the pad body 1.

[0050] The benefits of the spring self-locking mechanism 4 are as follows: First, the bottom beam no longer needs to have rectangular limiting holes in the front and rear directions, making the processing of the bottom beam simpler and significantly reducing manufacturing costs; Second, the two springs can provide stable self-locking force at any position on the bottom surface of the bottom beam, allowing the bottom beam to be installed at any position in the front and rear directions, achieving stepless adjustment and greatly improving installation flexibility; Third, the self-locking is naturally formed by the elastic rebound force of the springs, eliminating the need for additional bolts, pins, or other locking components. The installation process can be completed simply by pressing, making operation convenient.

[0051] As attached Figure 8As shown, the pad body 1 includes a base plate 11, which is generally rectangular or square. Intersecting reinforcing ribs 12 extend upwards from the upper surface of the base plate 11, perpendicular to each other, dividing the interior of the pad 100 into multiple squares. The upper surface of the reinforcing ribs 12 constitutes the upper surface of the pad body 1, i.e., the bearing surface, used to support the bottom beam above. This arrangement of reinforcing ribs 12 ensures the structural strength of the pad body 1 while effectively reducing weight and saving materials. The snap-fit ​​parts 2 and the clearance parts 3 are distributed within the squares formed by the reinforcing ribs 12. This structural layout allows the reinforcing ribs 12 to provide structural support while also isolating the snap-fit ​​and clearance grooves within their respective squares, resulting in a compact structure, good overall integrity, and ease of mold forming.

[0052] It should be noted that although the above description uses the inverted buckle and the clearance groove as examples, the specific forms of the snap-fit ​​part 2 and the clearance part 3 are not limited to this. For those skilled in the art, several improvements and equivalent substitutions can be made without departing from the spirit and principle of the present invention. As long as the functions of detachable connection and stacking can be achieved, other conventional snap-fit ​​structures and clearance structures are also within the protection scope of the present invention. For example, the shape of the pad 100 is not limited to a rectangle, but can also be a circle or other polygons; the number and distribution of the inverted buckle and the clearance groove can be adjusted according to actual load-bearing requirements; the specific form of the spring self-locking mechanism 4 can also have conventional variations.

[0053] Reference Appendix Figure 5-12 As shown, the present invention also provides a load-bearing assembly, including an outer component 200 and at least one stackable pad 100; the outer component 200 is specifically a bottom beam, which is a long strip-shaped component with a roughly rectangular or similar cross-section, and has outwardly extending protrusions 201 on both sides, which are connected to the topmost pad 100 by an inverted snap-fit ​​connection. The advantages of this load-bearing assembly are: first, the system is simple, requiring only a bottom beam and pads 100 of the same specification, eliminating the need for pads 100 of different heights or additional heightening accessories, thus reducing material types and inventory costs; second, on-site installation is flexible, allowing construction personnel to decide whether to increase the height and how many layers to add based on actual terrain and usage requirements, demonstrating strong adaptability; third, the entire installation process is mainly based on pressing operations, requiring no special tools, resulting in high construction efficiency.

[0054] When there is only one pad 100, the two sides of the bottom beam are connected to the undercut snaps of the pad 100. The bottom surface of the bottom beam is pressed against the spring self-locking mechanism 4 of the pad 100. The rebound force generated by the deformation of the left spring 41 and the right spring 42 forms a frictional self-locking in the left and right directions, allowing the bottom beam to be infinitely positioned in any position in the front and back directions. The specific installation steps are as follows: Place the pad 100 in the predetermined position, then align the bottom beam above the pad 100. First, insert the protrusion 201 on one side of the bottom beam obliquely into the undercut on the corresponding side of the pad 100. Then press down on the other side of the bottom beam so that the protrusion 201 on that side is inserted into the corresponding undercut. During the pressing process, the bottom surface of the bottom beam simultaneously squeezes the left spring 41 and the right spring 42 in the middle of the pad 100. After the springs deform, they generate a rebound force, forming a self-locking on the bottom beam in the left and right directions. The bottom beam can be adjusted arbitrarily in the front and back directions to achieve infinite positioning.

[0055] When a height increase is required, at least two pads 100 are used. Any two adjacent pads 100 are stacked and fixed by rotating them 180 degrees relative to each other, causing the undercut of the lower pad 100 to insert into the clearance groove of the upper pad 100 and form a snap-fit. The specific installation steps are as follows: First, place the lower pad 100. Then, rotate the upper pad 100 180 degrees so that the clearance groove of the upper pad 100 aligns with the undercut of the lower pad 100. Press the upper pad 100 down, and the undercut of the lower pad 100 inserts into the clearance groove of the upper pad 100 and hooks onto the edge of the clearance groove, completing the stacking and fixing of the two pads 100. Then, following the same method, install the bottom beam onto the undercut of the top pad 100. After stacking, the upper pad 100 retains all its original functions, the installation of the bottom beam is not affected in any way, and the undercut of the lower pad 100 will not interfere with the bottom beam.

[0056] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A stackable pad, characterized in that, Including the pad block body; The pad body is provided with a snap-fit ​​part and a clearance part; When the pad body is used alone, the snap-fit ​​part is used to connect to external components in a detachable manner; When two identical pad bodies are stacked one on top of the other, the two pad bodies are in the first relative position after being rotated 180 degrees relative to each other. At this time, the snap-fit ​​part of the lower pad body is converted to cooperate with the avoidance part of the upper pad body to achieve the vertical stacking and fixing.

2. The stackable pad according to claim 1, characterized in that: The pad body has four corner areas, each corner area is provided with a set of connecting units, each set of connecting units includes a latching part and a clearance part, and the latching part and the clearance part are distributed left and right in the corner area.

3. The stackable pad according to claim 2, characterized in that: In the four corner areas, the two sets of connecting units located diagonally have their latching parts and clearance parts distributed in the same left and right positions, so that after the pad is rotated 180 degrees, the latching parts and clearance parts of the upper and lower pad bodies are directly opposite each other in the vertical direction.

4. The stackable pad according to claim 1, characterized in that: The pad body is provided with a spring self-locking mechanism in the middle, and the top of the spring self-locking mechanism is higher than the upper surface of the pad body. When installed with the first external component, the bottom surface of the first external component presses the spring self-locking mechanism, causing the spring self-locking mechanism to undergo elastic deformation. The rebound force of the spring self-locking mechanism forms a self-lock on the first external component.

5. The stackable pad according to claim 4, characterized in that: The spring self-locking mechanism consists of a left spring and a right spring; both the left and right springs extend obliquely upwards from bottom to top, with their top ends protruding above the upper surface of the pad body; when installed with the first external component, the bottom surface of the first external component presses against the left and right springs, causing the left spring to undergo clockwise elastic deformation and the right spring to undergo counterclockwise elastic deformation, and the rebound force of the two springs forms a self-locking mechanism on the first external component in the left-right direction.

6. The stackable pad according to claim 1, characterized in that: The pad body includes a base plate and intersecting reinforcing ribs extending upward from the upper surface of the base plate, the upper surface of the reinforcing ribs forming the upper surface of the pad body; the snap-fit ​​portion and the clearance portion are arranged within the square formed by the reinforcing ribs.

7. The stackable pad according to any one of claims 1-6, characterized in that: The buckle part is an inverted buckle, and the clearance part is a clearance groove.

8. A load-bearing assembly, characterized in that: It includes an external component and at least one stackable pad as described in claim 7; the external component is a bottom beam, the two sides of which are connected to the topmost pad via snap-fit ​​connections.

9. The load-bearing assembly according to claim 8, characterized in that: The number of pads is one, and the two sides of the bottom beam are connected to the pads by inverted snap fasteners; the bottom surface of the bottom beam is pressed against the spring self-locking mechanism of the pads, and the rebound force generated by the deformation of the left and right springs forms a friction self-locking in the left and right directions, so that the bottom beam can be infinitely positioned at any position in the front and back directions.

10. The load-bearing assembly according to claim 8, characterized in that: The number of pads is at least two. Any two adjacent pads can be rotated 180 degrees relative to each other so that the inverted part of the lower pad is inserted into the clearance groove of the upper pad and a snap-fit ​​is formed to achieve stacking and fixing.

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