A universal shuttle for traction of steel strand bundles in bridges

Abstract

This invention provides a universal shuttle for traction of steel strand bundles in bridges, comprising: a clamping part and an expansion block. The clamping part includes: clamping arms and a positioning ring. Multiple clamping arms are connected in series around the positioning ring to form a clamping cavity. The clamping arms can rotate on the positioning ring. Both ends of the clamping arms are bent towards the center of the positioning ring to form an inner arc surface and an outer arc surface. The inner arc surface of one end of the clamping arm is provided with clamping teeth. The expansion block is disposed in the clamping cavity. By pulling the expansion block with external force, the end of the clamping arm with clamping teeth rotates towards the center of the positioning ring. This invention can clamp the head of the steel strand bundle inserted into the clamping cavity by pulling the expansion block, thus enabling the bundled steel strands to be quickly pulled through the prestressed ducts. The clamped steel strands are pulled together without interference between them, solving the problem of kinking that easily occurs in traditional single steel strand transmission methods, ensuring construction quality, and the direct traction transmission speed is fast.

Description

Technical Field

[0001] This invention belongs to the field of prestressed technology in building engineering, specifically relating to a universal shuttle for traction of steel strand bundles in bridges. Background Technology

[0002] Tracing steel strands through long and winding ducts is a common prestressed construction technique in building engineering. Traditional techniques and equipment rely on methods such as binding, knotting, and temporary welding to fix the traction rope and steel strands. However, when encountering situations like the steel strand bundles used for bridge tensioning passing through prestressing ducts, the radius of the duct is almost the same as that of the steel strand bundles, making binding and knotting impossible. Furthermore, the steel strands have poor weldability and cannot be connected by welding. Traditional methods only allow for single-strand conveying or bundled top conveying. However, single-strand conveying can lead to kinking, affecting the quality of the bridge's prestressed system; while bundled top conveying is slow and inefficient, reducing the overall construction progress of the bridge.

[0003] Therefore, there is a need to provide an improved technical solution for the shortcomings of the existing technology for the universal shuttle head used for the traction of bridge steel strand bundles. Summary of the Invention

[0004] The purpose of this invention is to overcome the problems in the prior art where the method of transmitting steel strands during bridge tensioning affects the quality of the bridge prestressed system and has extremely low efficiency, thus reducing the overall construction progress of the bridge.

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

[0006] A universal shuttle for traction of bridge steel strand bundles includes: a clamping part and an expansion block. The clamping part includes: a clamping arm and a positioning ring. Multiple clamping arms are connected in series around the positioning ring to form a clamping cavity. The clamping arms are rotatable on the positioning ring. Both ends of the clamping arms are bent towards the center of the positioning ring to form an inner arc surface and an outer arc surface. The clamping arms are rotatable towards the center of the positioning ring. The inner arc surface of one end of the clamping arm is provided with clamping teeth. The expansion block is disposed in the clamping cavity. By pulling the expansion block with external force, the end of the clamping arm with the clamping teeth rotates towards the center of the positioning ring to clamp the bundled steel strands extending into the clamping cavity.

[0007] In the universal shuttle head for traction of bridge steel strand bundles as described above, preferably, the middle part of the clamping arm is provided with a through hole that matches the ring width of the positioning ring.

[0008] Both sides of the clamping arm are provided with limiting blocks corresponding to the through holes, and the limiting blocks are fixed on the positioning ring.

[0009] Preferably, the plurality of clamping arms are distributed at equal intervals on the positioning ring.

[0010] Preferably, the clamping arm is made of steel with spring-back capability.

[0011] Preferably, the expansion block is hemispherical in shape, so that the expansion block forms a pier and a tip, the pier corresponding to the direction of the clamping cavity, and the tip corresponding to the direction of external force traction.

[0012] Preferably, a traction rod is connected to the middle of the tip of the expansion block, and a binding ring is connected to the end of the traction rod away from the expansion block.

[0013] Preferably, the clamping teeth are detachably connected to the clamping arm by bolts.

[0014] Preferably, the clamping teeth include: teeth and a fixing plate, wherein a plurality of teeth are disposed at the front end of the fixing plate, and the length of the plurality of teeth increases sequentially toward the rear end of the fixing plate;

[0015] Both the rear end of the fixing plate and the inside of the clamping arm are provided with through holes for the shank of the bolt to pass through;

[0016] The outer arc surface of the clamping arm is provided with a concealing groove corresponding to the bolt rod.

[0017] Preferably, the diameter of the through hole is smaller than the diameter of the bolt head;

[0018] The nut of the bolt is placed in the corresponding concealing groove and does not protrude outward from the outer arc surface of the clamping arm.

[0019] Preferably, the spherical arc of the expansion block matches the arc of the inner arc surface of the clamping arm.

[0020] Beneficial effects: By connecting multiple clamping arms in series on the positioning ring, the present invention can generate confining pressure on the steel strand bundle, so that the steel strands on the outermost part of the steel strand bundle can be directly clamped by the clamping arms, and ensure that the generated clamping pressure can be transmitted to the steel strands in the central area of ​​the steel strand bundle, so that the steel strand bundle can be transmitted stably.

[0021] When the expansion block inside the clamping cavity is pulled by external force, under the influence of the weight of the bundled steel strands and friction, the expansion block allows the ends of multiple clamping arms with clamping teeth to rotate simultaneously toward the center of the positioning ring. This clamps the head of the steel strand bundle inserted into the clamping cavity, enabling the bundled steel strands to be quickly pulled through the prestressed ducts. By pulling the bundled steel strands together without interference between them, the problem of kinking that easily occurs in traditional single steel strand transmission methods can be solved, ensuring the quality of the bridge prestressed system. Furthermore, this invention allows for the direct pulling method to transmit the steel strand bundle, resulting in high work efficiency and fast transmission speed. It also solves the problems of slow speed and low efficiency of traditional top-feeding bundling methods.

[0022] This invention is small in size, and both ends of the clamping arms are curved. As a result, multiple clamping arms are connected in series on the positioning ring to form a streamlined shuttle head, which reduces resistance and allows the traction steel strand bundle to pass quickly through the curved prestressed channel, thereby improving work efficiency. Attached Figure Description

[0023] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. Wherein:

[0024] Figure 1 This is an overall schematic diagram of the present invention;

[0025] Figure 2 This is a front view of the clamping arm structure of the present invention;

[0026] Figure 3 for Figure 2 Enlarged view of point A in the middle;

[0027] Figure 4 This is a side view of the present invention;

[0028] Figure 5 This is a front view of the expansion block structure of the present invention;

[0029] Figure 6 This is a schematic diagram of the clamping of bundled steel strands in Embodiment 3 of the present invention.

[0030] In the diagram: 1. Clamping arm; 2. Positioning ring; 3. Clamping cavity; 4. Clamping teeth; 5. Expansion block; 6. Through hole; 7. Limiting block; 8. Traction rod; 9. Binding ring; 10. Bolt; 11. Teeth; 12. Fixing plate; 13. Masking groove. Detailed Implementation

[0031] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art are within the scope of protection of the present invention.

[0032] In the description of this invention, the terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," and "bottom," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and do not require the invention to be constructed and operated in a specific orientation; therefore, they should not be construed as limitations on the invention. The terms "connected" and "linked" used in this invention should be interpreted broadly. For example, they can refer to a fixed connection or a detachable connection; they can refer to a direct connection or an indirect connection through intermediate components. Those skilled in the art can understand the specific meaning of the above terms according to the specific circumstances.

[0033] The present invention will now be described in detail with reference to the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described herein can be combined with each other.

[0034] Example 1

[0035] A universal shuttle for traction of steel strand bundles in bridges, as shown in the reference. Figure 1 and Figure 5 It includes a clamping arm 1 and a positioning ring 2. Multiple clamping arms 1 are provided. The clamping arms 1 are made of steel to ensure their own strength and make the clamping stable. A through hole 6 matching the width of the positioning ring 2 is made in the middle of the clamping arm 1 so that the positioning ring 2 can pass through. In this way, multiple clamping arms 1 can be connected in a ring on the positioning ring 2, and the distance between each pair of adjacent clamping arms 1 is equal.

[0036] Reference Figure 2 , Figure 3 and Figure 4Both ends of the clamping arm 1 are bent towards the center of the positioning ring 2 to form an inner arc surface and an outer arc surface, thereby forming a spherical clamping cavity 3 through multiple clamping arms 1. A clamping tooth 4 is provided on the inner arc surface of the leftmost end of the clamping arm 1. The length of the clamping tooth 4 increases sequentially towards the right end of the clamping arm 1, so as to clamp the bundled steel strands through the clamping tooth 4. An expansion block 5 is provided in the clamping cavity 3. The expansion block 5 is hemispherical to form a pier and a tip, that is, the pier is flat and the tip is spherical. The curvature of the spherical surface is the same as the curvature of the inner arc surface of the clamping arm 1. The pier faces to the left and the tip faces to the right. The pier is set to reduce the space volume occupied by the expansion block 5 in the clamping cavity 3, thereby reserving enough space for the bundled steel strands. The stranded wire end is inserted; the pointed tip is designed to adapt to the inner arc surface of the clamping arm 1, so that when the expansion block 5 is pulled by external force from the pointed tip to contact the inner arc surface of the clamping arm 1, the end face of the pointed tip can completely coincide with the inner arc surface of the clamping arm 1, increasing the force-bearing surface of the expansion block 5 and the clamping arm 1 and improving the force-bearing effect; a traction rod 8 is welded or threaded to the middle of the pointed tip of the clamping arm 1 along its vertical direction. The traction rod 8 facilitates the operation of the expansion block 5 by the construction personnel. A binding ring 9 is welded or threaded to the traction end of the traction rod 8. The binding ring 9 is used to quickly bind the traction rope; the expansion block 5 is made of solid steel to ensure the hardness of the expansion block 5 itself and prevent it from being deformed by pressure due to interaction with the clamping arm 1.

[0037] Reference Figure 4In use, multiple clamping arms 1 can be threaded onto the positioning ring 2 as needed, maintaining a circular shape to form a clamping cavity 3. Simultaneously, two retractable and expandable openings are formed at both ends of the clamping cavity 3. These openings can accommodate bundles of steel strands of varying thicknesses, increasing the versatility of this universal shuttle. The bundle of steel strands is inserted into the left opening of the clamping cavity 3. If the left opening is too small for the bundle to pass through, the expansion block 5 can be pushed to the left, expanding the opening to a size sufficient for the bundle to pass through. Then, the end of the bundle of steel strands is pressed against the surface of the expansion block 5, and the expansion block 5 is continuously pushed towards the right opening until the tip of the expansion block 5 contacts the inner arc surface of the right clamping arm 1. Next, the traction rope is tied to the binding ring 9 and pulled. The traction force is transmitted through the binding ring 9 to the traction rod 8, and then through the traction rod 8 to the expansion block 5. At this point, the expansion... Block 5 generates an expansion force on the right cavity opening, which causes the left cavity opening to contract, thereby causing the clamping teeth 4 on the clamping arm 1 to clamp the bundled steel strand from the outermost periphery. When a traction force is applied to the expansion block 5 to pull the bundled steel strand, firstly, due to the weight of the bundled steel strand plus its own friction, the required traction force is relatively large. The force pulling the bundled steel strand is proportional to the weight of the bundled steel strand and the friction. Next, the force generated when pulling the bundled steel strand is converted into a clamping force on the bundled steel strand through the clamping arm 1. Thus, while applying a traction force to the bundled steel strand, it also generates clamping pressure from all directions of the bundled steel strand through the ring-shaped clamping arm 1, so that the whole bundled steel strand is clamped and covered. The end of the wire bundle that extends into the clamping cavity 3 is firmly fixed by the clamping teeth 4. Finally, the traction rope is pulled, and the bundled steel strand will move forward with the traction rope. Since the whole invention is a streamlined shuttle-shaped body, it can quickly and smoothly pass through long and curved pipes.

[0038] Example 2

[0039] Example 2 is basically the same as Example 1, except that, referring to Figure 1Two opposing circular limiting blocks 7 are set on each clamping arm 1, and both limiting blocks 7 are in contact with the clamping arm 1. The limiting blocks 7 can limit the position of the clamping arm 1 on the positioning ring 2, preventing multiple clamping arms 1 from gathering together and being unable to be clamped. Although it is possible to evenly spread the gathered clamping arms 1 on the positioning ring 2, this is not only time-consuming but also difficult to operate. Therefore, it is necessary to limit the position of each clamping arm 1 so that it can always maintain a normal clamping state, providing convenience for construction personnel and saving operation time. In addition, the diameter of the limiting block 7 is not greater than the side width of the clamping arm 1 that is in close contact with it. The purpose of this limitation is to prevent the limiting block 7 from protruding out of the outer arc surface of the clamping arm 1. The protruding part will rub against the prestressed pipe, increasing the shuttle resistance of this universal shuttle head, thus affecting the shuttle head's movement in the prestressed duct.

[0040] Example 3

[0041] Example 3 is basically the same as Example 1, except that the material of the clamping arm 1 is further specified, referring to... Figure 6 In actual construction, steel strands are all cylindrical. Therefore, for ease of construction, bundles of steel strands are also cylindrical in shape. However, the outermost arc of this cylindrical shape is not a pure circle, but more like an elliptical arc, and there is a certain space between adjacent steel strands. In order to ensure that the outermost steel strands are continuously clamped by the clamping arm 1, the clamping arm 1 must not only have hardness, but also have the ability to rebound. Therefore, the material of the clamping arm 1 should be set as spring steel or similar elastic steel, so that the clamping arm 1 can provide comprehensive outer clamping pressure on the bundle of steel strands, thereby applying pressure layer by layer from the outermost edge of the bundle of steel strands to the inner edge, ensuring that the entire bundle of steel strands is clamped and covered, and preventing it from detaching from the traction head during the traction process.

[0042] Example 4

[0043] Example 4 is basically the same as Example 1, except that, referring to Figure 2 and Figure 3The clamping teeth 4 are detachably connected to the clamping arm 1 via bolts 10. Specifically, the clamping teeth 4 include: teeth 11 and a fixing plate 12. Multiple teeth 11 are welded to the leftmost end of the fixing plate 12 and arranged along the length of the fixing plate 12. The length of the multiple teeth 11 increases sequentially towards the rightmost end of the fixing plate 12. The right end of the fixing plate 12 is exposed, and a hole is formed in this exposed portion. The diameter of this hole is adapted to the shank of the bolt 10. A hole is also provided at the left end of the clamping arm 1 for the shank of the bolt 10 to pass through, so that the shank of the bolt 10 simultaneously penetrates both the fixing plate 12 and the clamping arm 1. A concealing groove 13 is formed on the outer arc surface of the clamping arm 1 corresponding to the position of this hole. This concealing groove 13 matches the nut of the bolt 10, allowing the nut to be placed within the concealing groove. In step 13, after placing the nut in the shielding groove 13, ensure that the nut does not protrude beyond the outer arc surface of the clamping arm 1, so as to avoid its protrusion affecting the universal shuttle head's movement through the prestressed duct. The clamping teeth 4 are designed to be detachable because during the traction of bundled steel strands, the clamping teeth 4 will exert strong clamping pressure on the bundled steel strands. After too many uses, the clamping teeth 4 will inevitably be damaged, which will affect its normal use. Therefore, it is designed to be detachable, which makes it easy to replace. On the one hand, it ensures that the clamping capacity of the clamping arm 1 is always kept in the best condition. On the other hand, when the length of the teeth 11 of the clamping teeth 4 is not suitable for the bundled steel strands to be clamped, it can be replaced with suitable clamping teeth 4 in a detachable manner, which greatly improves the effectiveness of the invention.

[0044] It is understood that the above description is merely exemplary and the embodiments of this application do not limit the scope of the application.

[0045] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention shall be within the scope of protection of the pending claims of the present invention.

Claims

1. A universal shuttle for traction of steel strand bundles in bridges, characterized in that, include: The clamping part includes: a clamping arm and a positioning ring. A plurality of the clamping arms are connected in series around the positioning ring to form a clamping cavity. The clamping arms can rotate on the positioning ring. Both ends of the clamping arms are bent toward the center of the positioning ring to form an inner arc surface and an outer arc surface. The clamping arms can rotate toward the center of the positioning ring. The inner arc surface of one end of the clamping arm is provided with clamping teeth. An expansion block is provided in the clamping cavity. By pulling the expansion block with external force, the end of the clamping arm with the clamping teeth rotates toward the center of the positioning ring to clamp the bundled steel strands that extend into the clamping cavity. The clamping arm has a through hole in the middle that matches the ring width of the positioning ring; Both sides of the clamping arm are provided with limiting blocks corresponding to the through holes, and the limiting blocks are fixed to the positioning ring; The expansion block is hemispherical in shape, so that the expansion block forms a pier and a tip, the pier corresponding to the direction of the clamping cavity, and the tip corresponding to the direction of external force traction.

2. The universal shuttle head for bridge steel strand bundling and traction according to claim 1, characterized in that, The multiple clamping arms are evenly distributed on the positioning ring.

3. The universal shuttle head for bridge steel strand bundling and traction according to claim 1, characterized in that, The clamping arm is made of steel with spring-back capability.

4. A universal shuttle for bridge steel strand bundling and traction according to claim 1, characterized in that, A traction rod is connected to the middle of the tip of the expansion block, and a binding ring is connected to the end of the traction rod away from the expansion block.

5. A universal shuttle for traction of bridge steel strand bundles according to claim 1, characterized in that, The clamping teeth are detachably connected to the clamping arm by bolts.

6. A universal shuttle for bridge steel strand bundling and traction according to claim 5, characterized in that, The clamping teeth include: teeth and a fixing plate, wherein a plurality of teeth are disposed at the front end of the fixing plate, and the length of the plurality of teeth increases sequentially toward the rear end of the fixing plate; Both the rear end of the fixing plate and the inside of the clamping arm are provided with through holes for the shank of the bolt to pass through; The outer arc surface of the clamping arm is provided with a concealing groove corresponding to the bolt rod.

7. A universal shuttle for bridge steel strand bundling and traction according to claim 6, characterized in that, The diameter of the through hole is smaller than the diameter of the bolt head; The nut of the bolt is placed in the corresponding concealing groove and does not protrude outward from the outer arc surface of the clamping arm.

8. A universal shuttle for bridge steel strand bundling and traction according to claim 1, characterized in that, The spherical arc of the expansion block matches the arc of the inner arc surface of the clamping arm.

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