Web reinforcement positioning jig

Abstract

This utility model discloses a web reinforcement positioning jig, which includes a base with multiple vertical reinforcement positioning slots; it also includes a limiting component, which comprises a fixed seat and a rotating frame. A limiting rod is provided on one side of the rotating frame, and the limiting rod has vertical reinforcement positioning slots that correspond one-to-one with the positioning slots on the base and are located in the same vertical plane. The fixed seat and the rotating frame are equipped with transverse positioning sleeves for inserting longitudinal reinforcement positioning rods. After the web reinforcement is tied, this utility model eliminates the need to disassemble or move most of the components on the side of the web reinforcement positioning jig. Only the longitudinal reinforcement positioning rods and the rotating frame need to be removed to lift and transport the web reinforcement. When tying the next web reinforcement, the rotating frame is flipped back to its original position and the longitudinal reinforcement positioning rods are reinserted. This eliminates the need for extensive and repeated disassembly and assembly, reducing labor steps, alleviating labor intensity, and improving tying efficiency.

Description

Technical Field

[0001] This utility model relates to the field of bridge prefabrication construction technology, and in particular to a positioning jig for web reinforcement. Background Technology

[0002] Precast T-beams consist of two parts: a web and a top slab. The web, as the core load-bearing structure, plays a crucial role in the overall structural stability of the T-beam. The web reinforcement is primarily determined by binding vertical and longitudinal bars to form a reinforcement cage. Since the vertical and longitudinal bars have specific spacing requirements, this process is mainly completed on a web reinforcement positioning jig. The positioning jig allows for rapid positioning of the vertical and longitudinal bars, facilitating their binding.

[0003] The web reinforcement is mainly a deformed structure that is smaller at the top and larger at the bottom. The lower part is generally a larger horseshoe-shaped structure, and the upper part is a smaller rectangular structure. When using a web reinforcement positioning jig to assist in the binding of the reinforcement, most of the components on the side of the web reinforcement positioning jig need to be removed or moved to facilitate the hoisting and transportation of the web reinforcement. Not only is disassembly troublesome, but when binding the next web reinforcement, the removed or moved components must be reinstalled. In other words, there is a problem of repeated disassembly and assembly on a large scale, which greatly affects the binding efficiency. Utility Model Content

[0004] To address the above shortcomings, this utility model provides a web reinforcement positioning jig, which solves the problem that existing web reinforcement positioning jigs require extensive and repeated disassembly and assembly, thus affecting binding efficiency.

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

[0006] A web reinforcement positioning jig includes a base, wherein multiple vertical reinforcement positioning slots are distributed along the longitudinal direction of the base.

[0007] It also includes a limiting component, which is disposed next to the base. The limiting component includes a fixed seat and a rotating frame rotatably disposed on the top of the fixed seat. The rotating frame is provided with a limiting rod on the side facing the base. The limiting rod is arranged longitudinally, and multiple vertical steel bar limiting grooves are opened on the side away from the rotating frame. The vertical steel bar limiting grooves are located above the vertical steel bar positioning grooves, and the vertical steel bar limiting grooves and the vertical steel bar positioning grooves correspond one-to-one and are located on the same vertical plane.

[0008] Both the fixed base and the rotating frame are provided with horizontally arranged positioning sleeves, and longitudinal steel bar positioning rods are inserted into the positioning sleeves.

[0009] The limiting rod is located above the base, and when the rotating frame rotates outward, it can cause the limiting rod to flip outward.

[0010] Furthermore, the rotating frame is provided with L-shaped rotating rods on both sides. The horizontal part of the L-shaped rotating rod is at the bottom and the free end of the horizontal part is rotatably connected to the top two sides of the fixed base. When the horizontal part of the L-shaped rotating rod rotates to the horizontal state, it can abut against the top of the fixed base and cannot continue to rotate to the base side.

[0011] A connecting rod is provided between the vertical portions of the two rotating rods, and the limiting rod is provided on the connecting rod.

[0012] Furthermore, a slot is provided on the connecting rod, and the limiting rod is inserted into the slot to adjust the distance between the limiting rod and the rotating rod.

[0013] Furthermore, the connecting rod is provided with a locking element for locking the limiting rod.

[0014] Furthermore, the base is provided with a detachable longitudinal bar, and the vertical steel bar positioning groove is formed on the longitudinal bar;

[0015] The limiting rod is detachably mounted on the rotating frame.

[0016] Furthermore, there are multiple limiting components, which are longitudinally distributed beside the base;

[0017] The positioning sleeve and longitudinal steel bar positioning rod are provided at different heights on both sides of the fixed seat and rotating frame on each limiting component. The longitudinal steel bar positioning rods located at the same height or on the same side are connected to a common rod at their outer ends.

[0018] Furthermore, the base includes two longitudinally extending base base members, and multiple supporting rods are arranged laterally between the two base base members, with the multiple supporting rods distributed along the extension direction of the base base members.

[0019] The longitudinal rod is fixed to multiple supporting rods so that there is a certain distance between the longitudinal rod and the bottom surface of the base foundation.

[0020] Furthermore, the base component has a placement groove at the position corresponding to the receiving rod, and both ends of the receiving rod are placed in the placement groove.

[0021] Furthermore, the longitudinal bar has a groove-shaped cross-section with the groove facing upwards, and the vertical steel bar positioning groove is opened at the vertical part of the two longitudinal bars that are close to each other.

[0022] Furthermore, the web reinforcement positioning frame also includes a ladder, and the bottom of the ladder is equipped with self-locking casters.

[0023] Compared with the prior art, the beneficial effects of this utility model are as follows: After the web reinforcement positioning jig of this utility model is tied, it is not necessary to dismantle or move most of the components on the side of the web reinforcement positioning jig. Only the longitudinal reinforcement positioning rod and the flipping and rotating frame need to be removed to realize the hoisting and transportation of the web reinforcement. When tying the next web reinforcement, the flipping and rotating frame can be reset and the longitudinal reinforcement positioning rod can be reinserted. That is, there is no need for extensive repeated disassembly and assembly, reducing labor steps, reducing labor intensity, and improving tying efficiency. Attached Figure Description

[0024] To more clearly illustrate the technical solutions of the embodiments of this utility model, the accompanying drawings used in the description of the embodiments will be briefly introduced below.

[0025] Figure 1 This is a schematic diagram of the web reinforcement positioning frame of this utility model;

[0026] Figure 2 This is an exploded view of the base in this utility model;

[0027] Figure 3 This is a schematic diagram of the limiting component in this utility model;

[0028] Figure 4 This is a schematic diagram of the structure of the limiting component in this utility model when it flips outward;

[0029] Figure 5 This is a schematic diagram of the ladder used in this utility model.

[0030] The markings shown in the diagram are as follows: 10-base; 11-vertical rebar positioning groove; 12-longitudinal rod; 13-base foundation component; 14-receiving rod; 15-placement groove; 20-limiting component; 21-fixed seat; 22-rotating frame; 221-rotating rod; 222-connecting rod; 223-slot; 224-locking component; 23-limiting rod; 231-insertion rod; 24-vertical rebar limiting groove; 25-positioning sleeve; 26-longitudinal rebar positioning rod; 27-common rod; 30-ladder; 31-self-locking caster wheel. Detailed Implementation

[0031] 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. All other embodiments obtained by those skilled in the art based on the embodiments of the present utility model without creative effort are within the scope of protection of the present utility model.

[0032] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0033] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances. Furthermore, the technical features involved in the different embodiments of this utility model described below can be combined with each other as long as they do not conflict with each other.

[0034] Please refer to Figures 1 to 5 A preferred embodiment of this utility model provides a web reinforcement positioning frame, which includes a base 10, a limiting component 20, and a ladder 30.

[0035] The base 10 extends longitudinally and has a certain length to meet the length requirements of the web reinforcement that needs to be tied. The base 10 is fixed to the ground, and multiple vertical reinforcement positioning slots 11 are distributed along its longitudinal direction. The spacing between the vertical reinforcement positioning slots 11 is corresponding to the spacing between the vertical reinforcements of the web reinforcement that need to be tied.

[0036] In a preferred embodiment, for example, the base 10 includes two longitudinally extending base base members 13, which may be made of U-shaped steel. The two U-shaped steel base base members 13 are parallel to each other, placed horizontally on the ground, and locked to the ground by bolts or the like.

[0037] Multiple support rods 14 are arranged laterally between the two base base components 13, and the support rods 14 are distributed along the extension direction of the base base components 13. For example, the support rods 14 are made of steel, arranged in pairs, and are parallel to each other laterally. The multiple sets of support rods 14 are evenly distributed in the longitudinal direction of the two base base components 13.

[0038] A longitudinal bar 12 is provided on the receiving rod 14, and the longitudinal bar 12 is fixed on the receiving rod 14. A vertical rebar positioning groove 11 is opened on the longitudinal bar 12. The longitudinal bar 12 is fixed on multiple receiving rods 14 so that there is a certain distance between the longitudinal bar 12 and the bottom surface of the base foundation component 13. The space formed by this distance is convenient for the binding of the rebar.

[0039] Preferably, the longitudinal bar 12 has a groove-shaped cross-section with the groove facing upwards, and the vertical rebar positioning groove 11 is formed at the vertical portions of the two longitudinal bars 12 that are close to each other. In an exemplary embodiment, the longitudinal bar 12 is made of channel steel and is connected to the receiving rod 14 by welding. In this case, the vertical rebar positioning groove 11 is formed at the leg position of the channel steel.

[0040] It is understandable that the vertical rebar positioning groove 11 is opened from top to bottom and does not extend to the bottom of the groove of the longitudinal rod 12, which has a groove-shaped structure. That is, there is a certain height difference between the bottom of the vertical rebar positioning groove 11 and the bottom of the groove of the longitudinal rod 12. At this time, when the vertical rebar is placed in the vertical rebar positioning groove 11 for positioning, there is a certain gap between the vertical rebar and the bottom of the groove of the longitudinal rod 12, or in other words, there is a certain space to facilitate the binding of the rebar.

[0041] In some preferred embodiments, the longitudinal bar 12 is detachably mounted on the base 10. In this case, the longitudinal bar 12 can be replaced to use longitudinal bars 12 with different spacing of vertical steel bar positioning grooves 11, thereby enabling the use of web steel bars of different specifications and types.

[0042] In this exemplary embodiment, the base base 13 has a placement groove 15 at a position corresponding to the receiving rod 14, and both ends of the receiving rod 14 are placed in the placement groove 15. The placement grooves 15 on the two base bases 13 can just accommodate the receiving rod 14. At this time, when the receiving rod 14 is placed in the placement groove 15, since the receiving rod 14 is fixedly connected to the longitudinal rod 12, the longitudinal rod 12 cannot move on the horizontal plane, and the vertical rebar positioning groove 11 is fixed on the horizontal plane. When it is necessary to replace the longitudinal rod 12, the longitudinal rod 12 can be lifted upwards to remove it from the base base 13, and then another longitudinal rod 12 can be inserted.

[0043] The limiting component 20 is disposed beside the base 10. In this exemplary embodiment, the limiting component 20 is placed beside the base 10 and its position is fixed, requiring no relocation. Of course, it can also be relocated or disassembled as a whole if necessary.

[0044] The limiting assembly 20 includes a fixed base 21 and a rotating frame 22 rotatably mounted on top of the fixed base 21. The rotating frame 22 has a limiting rod 23 on its side facing the base 10. The limiting rod 23 is longitudinally arranged, and multiple vertical rebar limiting grooves 24 are formed on the side opposite to the rotating frame 22. The vertical rebar limiting grooves 24 are located above the vertical rebar positioning grooves 11, and each vertical rebar limiting groove 24 corresponds to one of the vertical rebar positioning grooves 11 on the same vertical plane. The vertical rebar limiting grooves 24 are used to limit the movement of the vertical rebars. The vertical rebar positioning groove 11 is mainly used to position the bottom of the vertical rebar. After the bottom of the vertical rebar is positioned, the upper part or top of the vertical rebar also needs to be positioned or limited to maintain its vertical state. At this time, by setting a vertical rebar limiting groove 24 above the vertical rebar positioning groove 11, and the vertical rebar limiting groove 24 and the vertical rebar positioning groove 11 are located on the same vertical plane, the upper part or top of the vertical rebar can be positioned or limited by the vertical rebar limiting groove 24, so that each vertical rebar can be positioned in an upright state.

[0045] Both the fixed base 21 and the rotating frame 22 are equipped with horizontally arranged positioning sleeves 25. Longitudinal reinforcing bar positioning rods 26 are inserted into the positioning sleeves 25. These rods provide height positioning; the longitudinal reinforcing bars are positioned by placing them on the positioning rods 26. Since the longitudinal reinforcing bar positioning rods 26 are inserted into the positioning sleeves 25, they can be removed after the web reinforcement is tied. The longitudinal reinforcing bar positioning rods 26 have a certain length to achieve the receiving and positioning of all longitudinal reinforcing bars at that location in the web reinforcement.

[0046] The limiting rod 23 is located above the base 10, and when the rotating frame 22 rotates outward, it can drive the limiting rod 23 to flip outward. When the rotating frame 22 drives the limiting rod 23 to flip outward, it can move the limiting rod 23 away, and at this time it will not block the tied web reinforcement.

[0047] In one exemplary implementation, each vertical reinforcing bar is placed obliquely into its respective vertical reinforcing bar positioning groove 11, with the upper side of the vertical reinforcing bar positioned within the vertical reinforcing bar limiting groove 24. At this point, the vertical reinforcing bars maintain a vertical orientation and a preset spacing. Then, the longitudinal reinforcing bar positioning rod 26 is inserted into the positioning sleeves 25 at different heights. After insertion, the longitudinal reinforcing bar is placed on the longitudinal reinforcing bar positioning rod 26 and abuts against the inward-facing side of the vertical reinforcing bar, thus achieving the positioning of the longitudinal reinforcing bar. Once the vertical and longitudinal reinforcing bars are positioned, that is... Binding can be performed; after binding, first pull out the longitudinal reinforcement positioning rod 26, then flip the rotating frame 22. The rotating frame 22 drives the limiting rod 23 to flip outward, so that the limiting rod 23 moves away. At this time, the fixed seat 21, the rotating frame 22 and the limiting rod 23 do not overlap with the web reinforcement in the vertical projection. Then the bound web reinforcement can be lifted vertically by the hoisting equipment to realize the hoisting and transfer of the web reinforcement. After the web reinforcement is hoisted and transferred out of the web reinforcement positioning jig, the rotating frame 22 drives the limiting rod 23 to flip inward and reset, waiting for the positioning and binding of the next web reinforcement. With the web reinforcement positioning jig of this utility model, after the web reinforcement is tied, it is not necessary to dismantle or move most of the side parts of the web reinforcement positioning jig. Only the longitudinal reinforcement positioning rod and the flipping and rotating frame need to be removed to realize the hoisting and transportation of the web reinforcement. When tying the next web reinforcement, the flipping and rotating frame can be reset and the longitudinal reinforcement positioning rod can be reinserted. That is, there is no need for extensive repeated disassembly and assembly, reducing labor steps, reducing labor intensity, and improving tying efficiency.

[0048] Preferably, the rotating frame 22 has L-shaped rotating rods 221 on both sides. The horizontal portion of the L-shaped rotating rods 221 is at the bottom, and the free end of the horizontal portion is rotatably connected to the top sides of the fixed base 21. When the horizontal portion of the L-shaped rotating rods 221 rotates to a horizontal state, it can abut against the top of the fixed base 21 and cannot continue to rotate towards the base 10. The fixed base 21 is located next to the base 10, and its vertical projection does not overlap with the base 10. When the horizontal portion of the rotating rods 221 of the rotating frame 22 rotates to a horizontal state, it can abut against the top of the fixed base 21. At this time, the rotating frame 22 remains stationary. The vertical projection of the rotating frame 22 may or may not overlap with the base 10. A connecting rod 222 is provided between the vertical parts of the two rotating rods 221. A limiting rod 23 is provided on the connecting rod 222. When the rotating rod 221 of the rotating frame 22 rotates to a horizontal state in the horizontal part, it can abut against the top of the fixed seat 21 and keep the rotating frame 22 stationary. The limiting rod 23 overlaps with the base 10 in the vertical projection. At this time, the vertical steel bar limiting groove 24 on the limiting rod 23 overlaps with the base 10 in the vertical projection, which allows the upper part of the vertical steel bar to be inserted into the vertical steel bar limiting groove 24.

[0049] The connecting rod 222 has a slot 223, and the limiting rod 23 is inserted into the slot 223 to adjust the distance between the limiting rod 23 and the rotating rod 221. By adjusting the position of the limiting rod 23, it can be adapted to vertical reinforcing bars of different sizes. This method also allows the limiting rod 23 to be detachably installed on the connecting rod 222 for easy replacement. By replacing the limiting rod 23, limiting rods 23 with different spacing in the vertical reinforcing bar limiting grooves 24 can be used to adapt to the use of web reinforcing bars of different specifications and types. In a preferred embodiment, the limiting rod 23 is provided with an insert rod 231, which is perpendicular to the limiting rod 23 and inserted into the slot 223 to install the limiting rod 23 on the connecting rod 222.

[0050] The connecting rod 222 is provided with a locking member 224 for locking the limiting rod 23. The locking member 224 is a locking bolt. The connecting rod 222 has a screw hole that extends to the slot 223. When the locking member 224, which is a locking bolt, is screwed in and its inner end abuts against the insert rod 231, the insert rod 231 is fixed, that is, the limiting rod 23 is fixed.

[0051] Considering the definite length of the web reinforcement, if the length of a limiting rod 23 is approximately equal to the length of the web reinforcement, it would be difficult to flip the matching rotating frame 22. In a preferred embodiment, there are multiple limiting components 20, which are longitudinally distributed beside the base 10. In this case, there are multiple limiting rods 23, and the length of the multiple limiting rods 23 covers the length of the web reinforcement. At this time, the vertical reinforcement limiting groove 24 can cover the length of the web reinforcement. Since the length of the limiting rods 23 is relatively short, the length of the matching rotating frame 22 is also relatively short, making it easy to flip.

[0052] Each limiting component 20 has a positioning sleeve 25 and a longitudinal rebar positioning rod 26 at different heights on both sides of the fixed seat 21 and the rotating frame 22. The longitudinal rebar positioning rods 26 at the same height or on the same side are connected to a common rod 27 at their outer ends. By setting positioning sleeves 25 at different heights on both sides of the fixed seat 21 and the rotating frame 22 and inserting longitudinal rebar positioning rods 26, the longitudinal rebars are positioned. Since the longitudinal rebar positioning rods 26 at the same height or on the same side are connected to a common rod 27 at their outer ends, when inserting or removing the longitudinal rebar positioning rods 26, only one common rod 27 needs to be operated to insert or remove multiple longitudinal rebar positioning rods 26. In this exemplary embodiment, the longitudinal rebar positioning rods 26 at the same height are connected to a common rod 27 at their outer ends, that is, two longitudinal rebar positioning rods 26 are connected to a common rod 27 at their outer ends. Therefore, only one common rod 27 needs to be operated to operate two longitudinal rebar positioning rods 26 at the same height, reducing the number of operations.

[0053] Considering the considerable height of the web reinforcement bars, which necessitates working at height during tying, a preferred embodiment of this invention includes a ladder 30. Workers climb the ladder to perform tying at the upper positions. The bottom of the ladder 30 is equipped with self-locking casters 31, facilitating movement to a specific location for tying web reinforcement bars at different positions. When moved to a designated position, the self-locking casters 31 lock in place, preventing further movement and ensuring the ladder 30 remains fixed in one position, thus preventing accidental displacement during operations.

[0054] The above description is merely a specific embodiment of this utility model, but the protection scope of this utility model is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this utility model should be included within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the protection scope of the claims.

Claims

1. A web reinforcement positioning jig, comprising a base (10), wherein the base (10) has a plurality of vertical reinforcement positioning slots (11) distributed along its longitudinal direction, characterized in that, It also includes a limiting component (20), which is disposed next to the base (10). The limiting component (20) includes a fixed seat (21) and a rotating frame (22) rotatably disposed on the top of the fixed seat (21). The rotating frame (22) is provided with a limiting rod (23) on the side facing the base (10). The limiting rod (23) is arranged longitudinally, and a plurality of vertical steel bar limiting grooves (24) are opened on the side away from the rotating frame (22). The vertical steel bar limiting grooves (24) are located above the vertical steel bar positioning grooves (11), and the vertical steel bar limiting grooves (24) and the vertical steel bar positioning grooves (11) are located on the same vertical plane in a one-to-one correspondence. Both the fixed base (21) and the rotating frame (22) are provided with horizontally arranged positioning sleeves (25), and longitudinal steel bar positioning rods (26) are inserted into the positioning sleeves (25); The limiting rod (23) is located above the base (10), and when the rotating frame (22) rotates outward, it can drive the limiting rod (23) to flip outward.

2. The web reinforcement positioning jig according to claim 1, characterized in that, The rotating frame (22) is provided with L-shaped rotating rods (221) on both sides. The horizontal part of the L-shaped rotating rod (221) is at the bottom and the free end of the horizontal part is rotatably connected to the top two sides of the fixed seat (21). When the horizontal part of the L-shaped rotating rod (221) rotates to the horizontal state, it can abut against the top of the fixed seat (21) and cannot continue to rotate to the side of the base (10). A connecting rod (222) is provided between the vertical portions of the two rotating rods (221), and the limiting rod (23) is provided on the connecting rod (222).

3. The web reinforcement positioning jig according to claim 2, characterized in that, The connecting rod (222) has a slot (223) and the limiting rod (23) is inserted into the slot (223) to adjust the distance between the limiting rod (23) and the rotating rod (221).

4. The web reinforcement positioning jig according to claim 3, characterized in that, The connecting rod (222) is provided with a locking element (224) for locking the limiting rod (23).

5. The web reinforcement positioning jig according to claim 1, characterized in that, The base (10) is provided with a detachable longitudinal rod (12), and the vertical steel bar positioning groove (11) is opened on the longitudinal rod (12); The limiting rod (23) is detachably mounted on the rotating frame (22).

6. The web reinforcement positioning jig according to claim 1, characterized in that, There are multiple limiting components (20), and the multiple limiting components (20) are longitudinally distributed beside the base (10); On each limiting assembly (20), the fixed seat (21) and the rotating frame (22) are provided with positioning sleeves (25) and longitudinal steel bar positioning rods (26) at different heights on both sides. The longitudinal steel bar positioning rods (26) located at the same height or on the same side are connected to a common rod (27) at their outer ends.

7. The web reinforcement positioning jig according to claim 5, characterized in that, The base (10) includes two longitudinally extending base base members (13), and multiple supporting rods (14) are arranged laterally between the two base base members (13). The multiple supporting rods (14) are distributed along the extension direction of the base base members (13). The longitudinal bar (12) is fixed on multiple supporting bars (14) such that there is a certain distance between the longitudinal bar (12) and the bottom surface of the base base (13).

8. The web reinforcement positioning jig according to claim 7, characterized in that, The base component (13) has a placement groove (15) at a position corresponding to the receiving rod (14), and both ends of the receiving rod (14) are placed in the placement groove (15).

9. The web reinforcement positioning jig according to claim 7 or 8, characterized in that, The longitudinal bar (12) has a groove-shaped cross-section with the groove facing upwards, and the vertical steel bar positioning groove (11) is opened at the vertical part of the two longitudinal bars (12) that are close to each other.

10. The web reinforcement positioning jig according to claim 1, characterized in that, It also includes a ladder (30), the bottom of which is provided with self-locking casters (31).

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