A truss floor steel bar welding device

Abstract

The application discloses a truss floor support plate steel bar welding device, and relates to the technical field of building component processing, which comprises a conveying line, a plurality of steel bars arranged in the conveying line and steel bars, one end of the conveying line is provided with a guide plate, so that the steel bars and the steel bars are extruded and attached, both sides of the one end of the conveying line are provided with welding machines, the other end of the conveying line is internally provided with a first plasticizing mechanism and a second plasticizing mechanism for bending and shaping the steel bars, the first plasticizing mechanism comprises guide rails symmetrically arranged on both sides of the conveying line, a sliding piece is slidably arranged on the top of each guide rail, a first type of connecting piece is rotatably arranged at the end of the sliding piece, and a second type of connecting piece is rotatably arranged at the end of the first type of connecting piece through bridging. The truss floor support plate steel bar welding device disclosed by the application has the effects of high stability, high structural strength and functionality.

Description

Technical Field

[0001] This invention relates to the field of building component processing technology, and in particular to a welding device for reinforcing steel bars in truss floor decking. Background Technology

[0002] Truss floor decking is a composite component widely used in modern building floor construction. It consists of an upper concrete layer, a lower profiled steel sheet, and a steel truss in the middle that serves as a connection and processing element. The steel truss mainly includes upper chord steel bars, lower chord steel bars (steel bars), and wavy curved web steel bars (steel edges), which are connected by resistance spot welding.

[0003] Currently, the industry commonly uses automated truss welding production lines for fabrication. On these lines, the web reinforcement bars are drawn out from a wire feeding frame, straightened, and then fed into a wave bending mechanism, where they are continuously bent into a regular wave shape. They are then fed together with the upper and lower chord reinforcement bars into a welding unit for spot welding. However, existing wave bending mechanisms (usually using one or more sets of opposing bending wheels or dies) can only produce web reinforcement bars with a standard wave shape. The ends of these bars are typically straight sections perpendicular to the truss length or oblique straight sections aligned with the wave tangent. This structure, after welding, results in... The two ends of the reinforcing bars are connected to the chord only by a single weld point. During the transportation, hoisting, and concrete pouring of the truss, this weld point is subjected to large alternating stress and shear force, which can easily become a fatigue weak point. This may lead to weld cracking or separation of the web member end from the chord, affecting the overall stability and load-bearing capacity of the truss. Moreover, the stability of the truss depends entirely on the strength of the end weld point. Once the welding parameters fluctuate or have defects, the reliability of the entire node will drop significantly. Therefore, it is urgent to develop a new welding device that can improve the connection performance of the web member end and enhance the overall stability of the truss. Summary of the Invention

[0004] This invention discloses a welding device for steel reinforcement in truss floor slabs, which aims to solve the technical problems of low end connection strength and poor stability of truss web reinforcement in the prior art.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A truss floor deck steel reinforcement welding device includes a conveyor line, a plurality of steel bars and steel bar edges erected inside the conveyor line, a guide plate installed at one end of the conveyor line, the guide plate being centrally located and close to the outer sides of two steel bar edges, causing the steel bar edges and steel bars to be squeezed and adhered together, welding machines installed on both sides of one end of the conveyor line, and a first shaping mechanism and a second shaping mechanism for bending and shaping the steel bar edges are provided inside the other end of the conveyor line;

[0007] The first molding mechanism includes guide rails symmetrically installed on both sides inside the conveyor line. Each guide rail has a sliding member slidably installed on its top. A type of connector is rotatably installed at the end of the sliding member. A type of connector is rotatably installed at the end of the type of connector through a bridge.

[0008] The second molding mechanism includes symmetrically fixed plates on both sides inside the conveyor line. The ends of the two types of connectors are rotatably connected to the plates. A back plate is distributed on the back of one end of the plate. An electrically controlled claw is fixedly installed on the end of the two types of connectors. Several evenly distributed hydraulic push rods are fixedly installed on the top of the conveyor line. The output ends of the hydraulic push rods are fixedly connected to the extrusion parts on both sides.

[0009] The first molding mechanism, in conjunction with the second molding mechanism, punches and bends the edge of the reinforcing bar into an inward-curving shape, thereby assisting the guide plate and the welding machine in welding the entire reinforcing bar and its edge.

[0010] Based on traditional truss floor deck reinforcement welding equipment and technology, this system incorporates alternating first and second shaping mechanisms. The first shaping mechanism creates a corrugated structure on the reinforcement edge while simultaneously performing an inward bend at the top of the corrugated end. The second shaping mechanism then laterally presses the bottom of the reinforcement edge to create an outward bend. Combined with the centered guidance of the guide plate, this allows the reinforcement edge and the reinforcement bar to come into contact. The inward bend of the reinforcement edge created by this equipment forms a "wrap" structure at the weld point, creating a certain mechanical interlock with the reinforcement bar, thus providing additional safety redundancy. Furthermore, the inward bend structure increases the welding contact area and improves the direction of force, transforming the weld point from bearing a single shear force to bearing partial compressive stress and combined force, greatly improving the static load strength and dynamic fatigue life of the joint.

[0011] In a preferred embodiment, the sliding member, the first type of connecting member, the bridging member, and the second type of connecting member are all engaged with the outside of the steel bar edge and the steel bar edge is stamped and shaped. A beveled member is symmetrically installed on both sides of the top of the conveyor line, and the beveled member obliquely squeezes the top of the raised steel bar edge.

[0012] Based on existing rebar edge bending technology, this invention incorporates interconnected components such as sliding parts, type I connectors, bridging components, and type II connectors. The rotation of these components around a point exerts pressure and push on the rebar edge, creating a V-shaped bend. Furthermore, the stepping displacement of the upper components, combined with an additional inclined surface component, applies inward pressure to the top of the V-shaped bend. This results in the inward-curving bend of the rebar edge forming a "wrap" structure at the weld point, creating a mechanical interlock with the rebar and providing additional safety redundancy. The inward-curving structure also increases the welding contact area and improves the direction of force, transforming the weld point from bearing a single shear force to bearing partial compressive stress and combined forces, significantly improving the static load strength and dynamic fatigue life of the joint.

[0013] In a preferred embodiment, the back plate is fixedly installed above the inner wall of the conveyor line, and the reinforcing bar edge passes through the plate and the back plate. The electrically controlled claw clamps the reinforcing bar edge on the outside and is symmetrically distributed with the back plate. The extruder is slidably distributed inside the plate and performs lateral extrusion on the bottom of the reinforcing bar edge.

[0014] By associating a plate platform and an electrically controlled claw structure at the end of the second-class connector, after the first molding mechanism completes the single folding process of the steel bar edge in a single operation, the folded end of the steel bar edge moves to the top of the plate platform. With the help of the electrically controlled claw, the plate platform, and the back plate restricting both sides of the folded end, and then through the lateral punching of the extruder, the bottom of the steel bar edge is turned outward. The outward structure greatly improves the steel bar skeleton produced by this equipment, which can significantly increase the welding contact area, improve the direction of force, and change the weld point from bearing a single shear force to bearing a part of compressive stress and combined force. This greatly improves the static load strength and dynamic load fatigue life of the connection node between the steel bar skeleton and the floor deck.

[0015] In a preferred embodiment, a plurality of lifting welding heads are fixedly installed inside the guide plate. The lifting welding heads are distributed on the top of the reinforcing bar and the edge of the reinforcing bar, and are used to weld and fix the reinforcing bar and the edge of the reinforcing bar.

[0016] By incorporating a built-in lifting welding head structure on the guide plate, the guide plate centers and brings together the steel bar edges and steel bars, while the lifting welding head simultaneously completes the welding process on the contact ends of the steel bars and steel bar edges, thereby significantly improving the stability and completeness of the steel bar skeleton fabrication process.

[0017] As can be seen from the above, the truss floor deck steel reinforcement welding device provided by the present invention has the following technical effects.

[0018] Based on traditional truss floor deck reinforcement welding equipment and technology, this system incorporates alternating first and second shaping mechanisms. The first mechanism creates a corrugated structure on the reinforcement edge while simultaneously bending the top of the corrugated end inwards. The second mechanism, on the other hand, laterally presses the bottom of the reinforcement edge, creating an outward bend. Combined with the centered guidance of the guide plate, this ensures the reinforcement edge and the reinforcement bar are in close contact. Consequently, the reinforcement skeleton produced by this equipment exhibits multiple effects:

[0019] Firstly, the inward bending of the reinforcing bar edge forms a "wrap" structure at the weld point, increasing the contact area with the upper reinforcing bar and thus providing additional safety redundancy. Furthermore, the inward bending structure increases the welding contact area and improves the direction of force, transforming the weld point from bearing a single shear force to bearing partial compressive stress and combined force, which greatly improves the static load strength and dynamic fatigue life of the joint.

[0020] Secondly, the outward-turned structure at the bottom of the reinforcing bar significantly increases the contact area between the reinforcing bar cage and the floor deck during welding, and improves the direction of force. This transforms the weld point from bearing a single shear force to bearing a combination of compressive stress and combined force, greatly improving the static load strength and dynamic fatigue life of the connection node between the reinforcing bar cage and the floor deck.

[0021] Thirdly, this invention improves upon existing welding equipment, requiring no large-scale modification of the production line, resulting in low modification costs and easy promotion. Furthermore, the structure is suitable for steel bars of various diameters and strengths, and can be widely applied to the production of truss floor decking of different specifications. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the overall structure proposed in this invention.

[0023] Figure 2 This is a side view of the overall structure proposed in this invention.

[0024] Figure 3 This is a side view of the welding state of the lifting welding head for the steel bar edge and steel bar strip proposed in this invention.

[0025] Figure 4 This is a schematic diagram of the hydraulic push rod structure proposed in this invention.

[0026] Figure 5 This is a schematic diagram of the chamfered surface structure proposed in this invention.

[0027] Figure 6 This is a schematic diagram of the two types of connecting parts proposed in this invention.

[0028] Figure 7 This is an exploded view of the first molding mechanism structure proposed in this invention.

[0029] Figure 8 This is a schematic diagram showing the state of the inclined surface component and the top edge of the reinforcing bar being pressed together, as proposed in this invention.

[0030] In the diagram: 1. Conveyor line; 101. Rebar strip; 102. Rebar edge; 2. Guide plate; 201. Lifting welding head; 3. Welding machine; 4. First molding mechanism; 401. Guide rail; 402. Sliding part; 4021. Outer arc opening; 403. Type I connector; 404. Bridge; 405. Type II connector; 406. Inclined part; 407. Electric push rod; 408. Wedge surface; 5. Second molding mechanism; 501. Platform; 5011. Through groove; 5012. Reinforcing surface; 502. Back plate; 503. Electric control claw; 504. Hydraulic push rod; 505. Extruded part; 5051. Chamfered surface. Detailed Implementation

[0031] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0032] The truss floor deck reinforcement welding device disclosed in this invention is mainly used in the scenario of welding and preparing the reinforcement skeleton of truss floor decks.

[0033] Reference Figures 1 to 8 A truss floor deck steel reinforcement welding device includes a conveyor line 1, a plurality of steel bars 101 and steel bar edges 102 erected inside the conveyor line 1, a guide plate 2 is installed at one end of the conveyor line 1, the guide plate 2 is centered and close to the outside of the two steel bar edges 102, causing the steel bar edges 102 and the steel bars 101 to be squeezed and adhered together, welding machines 3 are installed on both sides of one end of the conveyor line 1, and a first shaping mechanism 4 and a second shaping mechanism 5 are provided inside the other end of the conveyor line 1 to bend and shape the steel bar edges 102;

[0034] The first molding mechanism 4 includes guide rails 401 symmetrically installed on both sides inside the conveyor line 1. Each guide rail 401 has a sliding member 402 slidably installed on its top. A type of connector 403 is rotatably installed at the end of the sliding member 402. A type of connector 405 is rotatably installed at the end of the type of connector 403 through a bridge 404.

[0035] The second molding mechanism 5 includes a plate platform 501 symmetrically fixed on both sides inside the conveyor line 1. The end of the second type of connector 405 is rotatably connected to the plate platform 501. A back plate 502 is distributed on the back of one end of the plate platform 501. An electric control claw 503 is fixedly installed on the end of the second type of connector 405. Several evenly distributed hydraulic push rods 504 are fixedly installed on the top of the conveyor line 1. The output end of the hydraulic push rod 504 is fixedly connected to the extrusion parts 505 on both sides.

[0036] The first molding mechanism 4, in conjunction with the second molding mechanism 5, punches and bends the steel bar edge 102 into an inward-curving shape, thereby assisting the guide plate 2 and the welding machine 3 in welding the entire steel bar 101 and the steel bar edge 102.

[0037] In this embodiment: A worker uses a traction machine to pass several steel bars 101 and steel bar edges 102 through the end of the entire conveyor line 1. Simultaneously, the traction machine drives the entire steel bar 101 and steel bar edges 102 to move step-by-step along the interior of the conveyor line 1. During this process, the steel bar 101 and steel bar edges 102 pass sequentially through the first molding mechanism 4, the second molding mechanism 5, and the guide plate 2. First, the first molding mechanism 4 starts. When the steel bar edges 102 stop moving, the pushed sliding member 402, the first-type connecting member 403, and the second-type connecting member 405 arch upwards around the bridge 404. Simultaneously, the arching compresses and pushes the steel bar edges 102, causing deformation and generating V-shaped undulations. After a single pressing of the steel bar edges 102, the entire first molding mechanism 4 resets, and the traction machine drives the steel bar edges 102 to move step-by-step. The movement causes the corrugated part of the rebar edge 102 to move to the top of the platform 501. At this time, the two ends of the corrugated part of the rebar edge 102 will be clamped by the electric control claw 503 and the platform 501 and the back plate 502 respectively. The hydraulic push rod 504 is activated, and the hydraulic push rod 504 drives the extrusion piece 505 to push towards the platform 501, thereby forming a transverse stamping deformation at the bottom of the corrugated part of the rebar edge 102. After the stamping and shaping of the rebar edge 102 is completed, the traction machine that continues to run will drive the rebar edge 102 to move towards the welding machine 3. During this process, the horizontally distributed rebar edge 102 and rebar strip 101 will be gradually gathered by the guide plate 2 until the top of the rebar edge 102 and the rebar strip 101 above it are attached. The welding machine 3 will weld the rebar edge 102 and the rebar strip 101 together to complete the processing of the rebar skeleton.

[0038] Among them, electric push rods 407 are symmetrically installed on both sides of the top of the conveyor line 1. The electric push rods 407 are horizontally distributed on the side of the guide rail 401, and the output end of the electric push rod 407 is fixedly connected to the outside of the sliding member 402.

[0039] Furthermore, the sliding member 402 is provided with an outer arc opening 4021 on the outer side of the end of the first type of connector 403. When the first type of connector 403 rotates around the sliding member 402, the outer arc opening 4021 makes it easier to bend and shape the steel bar edge 102.

[0040] Reference Figures 4 to 6 , Figure 8In a preferred embodiment, the sliding member 402, the first type of connecting member 403, the bridging member 404, and the second type of connecting member 405 are all engaged with the outside of the steel bar edge 102 and the steel bar edge 102 is stamped and shaped. A inclined member 406 is symmetrically installed on both sides of the top of the conveyor line 1, and the inclined member 406 obliquely extrudes the top of the raised steel bar edge 102.

[0041] The pushed sliding member 402, the first type of connecting member 403 and the second type of connecting member 405 arch upward around the bridge 404. At the same time, the arching compresses and pushes the steel bar edge 102 to deform and generate a V-shaped fold. At the same time, the top of the fold end will be compressed with the inclined member 406, and then the side of the bridge 404 will undergo inward deformation.

[0042] Specifically, the bottom of the connection end of the first type connector 403, the second type connector 405, and the bridge 404 is provided with a wedge surface 408. When rotation occurs, the wedge surface 408 at the bottom of the first type connector 403 and the second type connector 405 will press and fit against the side of the bridge 404, thereby maintaining the horizontal state of the bridge 404, so that the oblique angles of the first type connector 403 and the second type connector 405 are equal, and the shape of the stamped steel bar edge 102 is uniform.

[0043] Reference Figures 4 to 6 In a preferred embodiment, the back plate 502 is fixedly installed on the upper inner wall of the conveyor line 1, and the reinforcing bar edge 102 passes through the plate 501 and the back plate 502. The electric control claw 503 squeezes and clamps the outer side of the reinforcing bar edge 102 and is symmetrically distributed with the back plate 502. The extrusion member 505 is slidably distributed inside the plate 501 and performs lateral extrusion on the bottom of the reinforcing bar edge 102. A through groove 5011 is provided through the middle of the plate 501, and the extrusion member 505 is slidably distributed inside the through groove 5011. The outer surface of the extrusion member 505 is provided with a chamfered surface 5051.

[0044] Driven by the hydraulic push rod 504, the extrusion component 505 first creates a lateral extrusion between the chamfered surface 5051 and the bottom of the steel bar edge 102, thereby facilitating the extrusion component 505 to shape the bottom of the steel bar edge 102.

[0045] Reference Figure 3 In a preferred embodiment, a plurality of lifting welding heads 201 are fixedly installed inside the guide plate 2. The lifting welding heads 201 are distributed on the top of the upper steel bar 101 and the steel bar edge 102, and are used to weld and fix the steel bar 101 and the steel bar edge 102.

[0046] After the stamping and shaping of the reinforcing bar edge 102 is completed, the traction machine continues to move the reinforcing bar edge 102 towards the welding machine 3. During this process, the horizontally distributed reinforcing bar edge 102 and reinforcing bar 101 are gradually brought together by the guide plate 2 until the top of the reinforcing bar edge 102 and the upper reinforcing bar 101 are in contact. The subsequent welding machine 3 will weld the two sides of the reinforcing bar edge 102 and the reinforcing bar 101, while the lifting welding head 201 will weld the tops of the two reinforcing bar edges 102 and the upper reinforcing bar 101 together. Since the top of the reinforcing bar edge 102 is bent into an inward shape by the inclined piece 406, the top of the reinforcing bar edge 102 will form a semi-enclosed shape on the upper reinforcing bar 101 (see reference). Figure 3 This improves the strength of the weld.

[0047] The back of the platform 501 is provided with a reinforcing surface 5012 to improve the structural strength of the platform 501.

[0048] Working principle: During use, the worker uses a traction machine to pass several steel bars 101 and steel bar edges 102 through the end of the entire conveyor line 1. Simultaneously, the traction machine is controlled to drive the entire steel bar 101 and steel bar edges 102 to move stepwise along the interior of the conveyor line 1. During this process, the steel bar 101 and steel bar edges 102 pass sequentially through the interior of the first molding mechanism 4, the second molding mechanism 5, and the guide plate 2. First, the electric push rod 407 of the first molding mechanism 4 is activated, and the output end of the electric push rod 407 extends outward and pushes... The sliding member 402 slides along the top of the guide rail 401. When the reinforcing bar edge 102 stops moving, the pushed sliding member 402, the first-type connecting member 403, and the second-type connecting member 405 arch upwards around the frame bridge 404. At the same time, the arching compresses and pushes the reinforcing bar edge 102 to deform and generate a V-shaped fold. Simultaneously, the top of the fold end will compress with the inclined member 406, and then the side of the frame bridge 404 will undergo inward deformation. After completing a single stamping of the reinforcing bar edge 102, the entire first molding mechanism... 4. Upon reset, the traction machine simultaneously moves the reinforcing bar edge 102 in a stepping motion, causing the folded portion of the reinforcing bar edge 102 to move to the top of the platform 501. At this point, both ends of the folded portion of the reinforcing bar edge 102 are clamped by the electric control claw 503 and by the platform 501 and the back plate 502, respectively. Meanwhile, the hydraulic push rod 504 is activated, driving the extruder 505 towards the platform 501, thereby creating a lateral stamping deformation at the bottom of the folded portion of the reinforcing bar edge 102, completing the stamping and shaping of the reinforcing bar edge 102. Afterwards, the traction machine continues to move the reinforcing bar edge 102 towards the welding machine 3. During this process, the horizontally distributed reinforcing bar edge 102 and reinforcing bar 101 are gradually brought together by the guide plate 2 until the top of the reinforcing bar edge 102 and the reinforcing bar 101 are in contact. The welding machine 3 and the lifting welding head 201 will weld the sides and top of the reinforcing bar edge 102 and the reinforcing bar 101 respectively, welding the reinforcing bar edge 102 and the reinforcing bar 101 together to complete the processing of the reinforcing bar skeleton. The specific state is shown in the attached figure. Figure 3 As shown.

[0049] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A truss floor deck reinforcement welding device, comprising a conveyor line (1), a plurality of reinforcing bars (101) and reinforcing bar edges (102) erected inside the conveyor line (1), characterized in that, One end of the conveyor line (1) is equipped with a guide plate (2), which is centered and close to the outside of the two steel bar edges (102), causing the steel bar edges (102) and the steel bar strip (101) to be squeezed and pressed together. Welding machines (3) are installed on both sides of one end of the conveyor line (1), and the other end of the conveyor line (1) is provided with a first shaping mechanism (4) and a second shaping mechanism (5) for bending and shaping the steel bar edges (102). The first molding mechanism (4) includes guide rails (401) symmetrically installed on both sides inside the conveyor line (1). Each guide rail (401) has a sliding member (402) slidably installed on its top. A type of connector (403) is rotatably installed at the end of the sliding member (402). A type of connector (405) is rotatably installed at the end of the type of connector (403) through a bridge (404). The second molding mechanism (5) includes a plate platform (501) symmetrically fixed on both sides inside the conveyor line (1), the end of the second type of connector (405) is rotatably connected to the plate platform (501), a back plate (502) is distributed on the back of one end of the plate platform (501), an electric control claw (503) is fixedly installed on the end of the second type of connector (405), and a number of evenly distributed hydraulic push rods (504) are fixedly installed on the top of the conveyor line (1), and the output end of the hydraulic push rod (504) is fixedly connected to the extrusion parts (505) on both sides. The first molding mechanism (4) and the second molding mechanism (5) are used to press and bend the steel bar edge (102) into an inwardly bent shape, thereby assisting the guide plate (2) and the welding machine (3) in welding the entire steel bar (101) and the steel bar edge (102); The sliding member (402), the first type of connector (403), the bridge (404), and the second type of connector (405) are all engaged with the outside of the steel bar edge (102) and stamp the steel bar edge (102) into shape. A sloping member (406) is symmetrically installed on both sides of the top of the conveyor line (1). The sloping member (406) obliquely extrudes the top of the raised steel bar edge (102). The back plate (502) is fixedly installed on the inner wall of the conveyor line (1), and the steel bar edge (102) passes through the plate (501) and the back plate (502). The electric control claw (503) squeezes and clamps the outside of the steel bar edge (102) and is symmetrically distributed with the back plate (502). The extrusion member (505) is slidably distributed inside the plate (501) and performs lateral extrusion on the bottom of the steel bar edge (102). The bottom of the first type of connector (403), the second type of connector (405), and the bridge (404) are all provided with wedge surfaces (408), and the wedge surfaces (408) and the sides of the bridge (404) are pressed together.

2. The truss floor deck reinforcement welding device according to claim 1, characterized in that, The guide plate (2) is internally fixedly equipped with several lifting welding heads (201). The lifting welding heads (201) are distributed on the top of the steel bar (101) and the steel bar edge (102) at the contact end, and are used to weld and fix the steel bar (101) and the steel bar edge (102).

3. The truss floor deck reinforcement welding device according to claim 1, characterized in that, Electric push rods (407) are symmetrically installed on both sides of the top of the conveyor line (1). The electric push rods (407) are horizontally distributed on the side of the guide rail (401), and the output end of the electric push rod (407) is fixedly connected to the outside of the sliding member (402).

4. The truss floor deck reinforcement welding device according to claim 1, characterized in that, The sliding member (402) has an outer arc opening (4021) on the outer side of its end close to the first type of connector (403).

5. The truss floor deck reinforcement welding device according to claim 1, characterized in that, A through groove (5011) is provided in the middle of the plate (501), and the extrusion member (505) is slidably distributed inside the through groove (5011).

6. The truss floor deck reinforcement welding device according to claim 1, characterized in that, The outer surface of the extrusion (505) is provided with a chamfered surface (5051).

7. The truss floor deck reinforcement welding device according to claim 1, characterized in that, The back of the platform (501) is provided with a reinforcing surface (5012).

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