Tensioning device for applying prestress to concrete pole

Abstract

The utility model discloses a tensioning device for applying prestress to a concrete pole, and belongs to the field of concrete pole production. The tensioning device comprises a bottom plate, a lower die is fixed to the upper end of the bottom plate, a steel bar frame is arranged on the lower die, pier heads are arranged at the two ends of steel bars of the steel bar frame, and the diameter of the pier heads is larger than that of the steel bars. A fixing mechanism and a traction mechanism are respectively arranged at two ends of the steel bar frame; the fixing mechanism comprises a mounting plate capable of sliding and adjusting in the axial direction of the reinforcing steel bar, and chuck assemblies corresponding to the pier heads one to one are arranged on the mounting plate; the traction mechanism comprises a supporting plate capable of sliding and adjusting in the axial direction of the reinforcing steel bar, an oil cylinder is arranged on the supporting plate, a connecting plate is fixed to a driving shaft of the oil cylinder, and chuck assemblies corresponding to the pier heads one to one are arranged on the connecting plate; the clamping head assembly comprises a clamping head, a positioning hole matched with the pier head is formed in the clamping head, the two sides of the clamping head are each provided with a clamping unit, and clamping blocks capable of sliding are arranged in the clamping units and can clamp the steel bars.

Description

Technical Field

[0001] The utility model belongs to the field of prestressed electric pole production, and in particular relates to a tensioning device for applying prestress to a concrete electric pole. Background Art

[0002] Concrete poles include prestressed and non-prestressed poles. Prestressed poles are primarily used in linear towers and critical power transmission lines. Their superior performance characteristics enable them to meet the demands of specialized applications such as high voltage and high loads. During the prestressed pole production process, prestressing is applied to the steel bars, followed by pouring concrete around the steel. After the concrete solidifies, the steel bars are cut through a specific process, placing the pole under stress. This production method significantly improves the pole's crack resistance and stiffness.

[0003] When applying tension, a clamp is used to grip both ends of the steel bar, and then a pulling force is applied to the clamp to tension it. If the grip of the clamped steel bar is not firm enough, it may be detached, resulting in tension failure, and in serious cases, a safety accident. For this purpose, a tensioning device for applying prestress to concrete poles is proposed. Utility Model Content

[0004] In view of the deficiencies in the prior art, the purpose of the present invention is to provide a tensioning device for applying prestress to concrete poles, thereby solving the problems in the prior art.

[0005] The purpose of the utility model can be achieved through the following technical solutions:

[0006] A tensioning device for applying prestress to a concrete pole comprises a base plate, a lower mold is fixed to the upper end of the base plate, a steel frame is provided in the mold cavity of the lower mold, a plurality of steel bars are provided on the steel frame and are evenly distributed in the axial direction, and pier heads are provided at both ends of the steel bars, and the diameter of the pier heads is larger than the diameter of the steel bars;

[0007] The two ends of the steel bar frame are respectively provided with a fixing mechanism and a traction mechanism; the fixing mechanism includes a mounting plate that can be slid and adjusted along the axial direction of the steel bar, and a plurality of clamping assemblies corresponding to the pier heads are provided on the mounting plate; the traction mechanism includes a support plate that can be slid and adjusted along the axial direction of the steel bar, and an oil cylinder is provided on the support plate, and a connecting plate is fixed on the driving shaft of the oil cylinder, and a plurality of clamping assemblies corresponding to the pier heads are provided on the connecting plate;

[0008] The clamp assembly includes a clamp, which is provided with a positioning hole that cooperates with the pier head. A clamping unit is provided on both sides of the clamp, and a slidable clamping block is provided in the clamping unit to clamp the steel bar.

[0009] Furthermore, the clamping unit includes a fixing frame fixed on the clamping head, and a cylinder is provided on the fixing frame to drive the clamping block to slide.

[0010] Furthermore, a through slot is respectively provided on opposite sides of the clamping head, and the through slot is communicated with the positioning hole; and the two clamping blocks are slidably fitted in the two through slots.

[0011] Furthermore, the clamping block is provided with an arc surface that cooperates with the steel bar.

[0012] Furthermore, a fixed shaft is provided on the chuck, a threaded hole is opened at the end of the fixed shaft, and a bolt passes through the mounting plate or the connecting plate and is screwed into the threaded hole to fix the fixed shaft to the mounting plate or the connecting plate.

[0013] Furthermore, the mounting plate is slidably connected to the base plate, and the sliding direction is parallel to the axial direction of the steel bar. Two first fixing plates are provided on the upper end of the base plate. A first screw rod is rotatably connected between the two first fixing plates. The first screw rod passes through the mounting plate and is threadedly connected thereto.

[0014] Furthermore, the thread lead angle of the first screw is smaller than the equivalent friction angle.

[0015] Furthermore, the support plate is slidably connected to the base plate, and the sliding direction is parallel to the axial direction of the steel bar. Two second fixed plates are provided on the upper end of the base plate. A second screw rod is rotatably connected between the two second fixed plates. The second screw rod passes through the support plate and is threadedly connected to it.

[0016] Furthermore, the thread lead angle of the second screw is smaller than the equivalent friction angle.

[0017] Beneficial effects of the utility model:

[0018] 1. A pier head is set at the end of the bottom plate steel bar, the diameter of the pier head is larger than the diameter of the steel bar, and a fixing mechanism and a traction mechanism are respectively set on both sides of the steel bar. The fixing mechanism and the traction mechanism are both provided with a clamping head assembly to clamp the pier heads on both sides of the steel bar respectively. Positioning holes are opened in the clamping head to cooperate with the pier head, and clamping units are respectively provided on both sides of the clamping head to clamp the steel bar. When the traction mechanism applies tension, the clamping block on the clamping unit can be tightly attached to the end face of the pier head, thereby preventing the pier head from being separated from the clamping head and causing tensioning failure.

[0019] 2. Fix the chuck to the connecting plate or the mounting plate through bolts to facilitate the disassembly and replacement of the chuck assembly at a later time. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0021] Figure 1 This is a schematic diagram of the overall structure of the tensioning device of the utility model;

[0022] Figure 2 It is a structural diagram of the steel bar skeleton of the utility model;

[0023] Figure 3 It is a structural diagram of the fixing mechanism of the utility model;

[0024] Figure 4 It is a structural diagram of the traction mechanism of the utility model;

[0025] Figure 5 It is a structural diagram of the chuck assembly of the utility model;

[0026] Figure 6 It is a structural diagram of the chuck of the utility model;

[0027] Figure 7 It is a schematic diagram of the clamping unit of the present utility model. DETAILED DESCRIPTION

[0028] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0029] like Figure 1 As shown, a tensioning device for applying prestress to a concrete pole comprises a base plate 1, the upper end of the base plate 1 is fixed by a lower mold 2, and a steel frame 3 is installed in the mold cavity at the upper end of the lower mold 2. Figure 2 As shown, a plurality of steel bars are arranged on the steel skeleton 3 and are evenly distributed in the circumferential direction. Piers 31 are respectively provided at both ends of the steel bars. Before pouring concrete, the piers at both ends of the steel bars in the steel skeleton 3 are clamped and tension is applied, and then the concrete is poured and the mold is closed (upper and lower molds are closed). After the concrete solidifies, the tension on the steel bars is removed, so that the pole itself is in a stressed state, thereby improving the crack resistance and rigidity of the pole.

[0030] In this embodiment, if Figure 2 As shown, an end plate 32 is provided at each end of the steel skeleton 3, and the steel bars pass through the end plates 32 and cooperate with each other, and the two ends of the steel bars are respectively processed by pier heads 31 to facilitate clamping; the end plates 32 are located at both ends of the lower mold 2 and cooperate with the mold cavity of the lower mold 2 to support the steel skeleton 3; an inner tube 33 is installed in the inner circle of the end plate 32, and the inner tube 33 forms a circular ring space with the lower mold 2 and the upper mold;

[0031] In the process of producing electric poles, concrete is poured into the lower mold 2, and then the upper mold and the lower mold 2 are combined and matched with the upper sleeve 33 to prepare a ring-shaped electric pole; after the concrete solidifies, the mold is separated (the upper mold and the lower mold 2 are separated), and then the tension at both ends of the steel bar is released, and then the pier head 31 of the steel bar is cut off, the end plate 32 is removed, and the inner tube 33 is pulled out to complete the preparation of the prestressed electric pole.

[0032] A fixing mechanism 4 and a pulling mechanism 5 are respectively provided on both sides of the steel bar skeleton 3. The fixing mechanism 4 is used to clamp and fix the pier head 31 at one end of the steel bar, and the pulling mechanism 5 clamps the pier head 31 at the other end of the steel bar and applies tension;

[0033] like Figure 3 As shown, the fixing mechanism 4 includes a mounting plate 41 that can be slidably adjusted on the upper end of the base plate 1. The sliding direction of the mounting plate 41 is parallel to the axial direction of the steel bar. A plurality of chuck assemblies 8 are fixed on the mounting plate 41 and are evenly distributed in the circumferential direction. By moving the mounting plate 41, the chuck assemblies can be aligned with the pier heads 31 of the steel bar one by one and clamped.

[0034] In this embodiment, the mounting plate 41 is slidably connected to the base plate 1, and the sliding direction is parallel to the axial direction of the steel bar. Two first fixing plates 12 are provided at the upper end of the base plate 1. A first screw rod 6 is rotatably connected between the two first fixing plates 12. The first screw rod 6 passes through the mounting plate 41 and is threadedly connected thereto. By rotating the first screw rod 6, the sliding position of the mounting plate 41 can be adjusted, thereby achieving assembly or separation of the fixing mechanism 4 and the pier head.

[0035] Furthermore, in order to ensure that the sliding position of the mounting plate 41 remains stable after adjustment, the first screw rod 6 needs to have a self-locking property, that is, the thread lead angle of the first screw rod 6 is smaller than the equivalent friction angle.

[0036] Of course, the method of driving the mounting plate 41 to slide and adjust includes but is not limited to the first screw rod 6 and other structures in this embodiment. In some embodiments, the mounting plate 41 can also be directly driven to slide and adjust by setting linear driving components such as cylinders and telescopic rods on the base plate 1.

[0037] In this embodiment, if Figure 4 As shown, the traction mechanism 5 includes a support plate 51 that can be slidably adjusted at the upper end of the base plate 1, and the sliding direction is parallel to the axial direction of the steel bar. A cylinder 52 is fixed to the upper end of the support plate 51, and a connecting plate 53 is fixed to the end of the drive shaft of the cylinder 52. A plurality of clamping assemblies 8 uniformly distributed in the circumferential direction are fixed to the connecting plate 53. By controlling the sliding of the support plate 51, the clamping assemblies 8 can be made to correspond one-to-one with the pier head 31 and clamp them. After the pier head 31 at the other end of the steel bar is clamped by the fixing mechanism 4, the cylinder 52 is started to apply tension to the steel bar.

[0038] In this embodiment, the support plate 51 is slidably connected to the base plate 1, and the sliding direction is parallel to the axial direction of the steel bar. Two second fixing plates 11 are provided at the upper end of the base plate 1. A second screw rod 7 is rotatably connected between the two second fixing plates 11. The second screw rod 7 passes through the support plate 51 and is threadedly connected thereto. By rotating the second screw rod 7, the sliding position of the support plate 51 can be adjusted; and the second screw rod 7 also has self-locking properties, and the thread lead angle of the second screw rod 7 is also smaller than the equivalent friction angle.

[0039] Of course, in some embodiments, the support plate 51 can also be directly driven to slide and adjust by setting linear drive components such as cylinders and telescopic rods on the base plate 1; however, the second screw rod 7 has self-locking properties, which can prevent the support plate 51 from moving during the application of tension.

[0040] like Figures 5 to 7 As shown, the clamp assembly 8 includes a clamp 81, and a fixed shaft 811 is provided on the clamp 81 to be fixedly connected to the mounting plate 41 and the connecting plate 53 respectively; a positioning hole 812 is formed at one end of the clamp 81, and the positioning hole 812 cooperates with the pier head 31, and a through slot 813 is formed on opposite sides of the clamp 81, and both through slots 813 are connected to the positioning hole 812; a clamping unit 82 is provided at each of the two through slots 813, and the clamping unit 82 includes a clamping block 82 that can cooperate with the through slot 813;

[0041] When the pier head 31 is inserted into the innermost part of the positioning hole 812, the two clamping blocks 82 are close to each other and can clamp the steel bar (instead of clamping the pier head 31). Moreover, since the diameter of the steel bar is smaller than the diameter of the pier head 31, when a tensile force is applied to the steel bar, the clamping blocks 832 can be in close contact with the end surface of the pier head 31, thereby preventing the pier head 31 from being separated from the clamping blocks 81.

[0042] In this embodiment, the clamping unit 82 includes a fixing frame 821 fixed to the outside of the clamping head 81, and a cylinder 822 is provided on the fixing frame 821. The end of the driving shaft of the cylinder 822 is fixed to the clamping block 82 and can drive the clamping block 82 to slide in the through groove 813.

[0043] Furthermore, in this embodiment, the clamping block 82 is provided with an arc surface 823 that cooperates with the steel bar.

[0044] In addition, in this embodiment, the chuck 81 is fixed to the mounting plate 41 and the connecting plate 53 by means of bolt connections; specifically, a threaded hole is provided at the end of the fixed shaft 811 of the chuck 81, and a bolt is passed through the mounting plate 41 or the connecting plate 53 and screwed into the threaded hole, thereby achieving a fixed connection between the linear chuck 81 and the mounting plate 41 or the connecting plate 53, thereby facilitating disassembly and replacement.

[0045] Working principle:

[0046] By setting a pier head 31 at the end of the steel bar of the bottom plate 1, the diameter of the pier head 31 is larger than the diameter of the steel bar, and a fixing mechanism 4 and a pulling mechanism 5 are respectively provided on both sides of the steel bar. The fixing mechanism 4 and the pulling mechanism 5 are both provided with a clamping head assembly 8 to respectively clamp the pier heads 31 on both sides of the steel bar. Positioning holes 812 are provided in the clamping head 81 to cooperate with the pier head 31, and clamping units 82 are respectively provided on both sides of the clamping head 81 to clamp the steel bar. When the pulling mechanism 5 applies tension, the clamping blocks 823 on the clamping units 82 can be tightly attached to the end faces of the pier head 31, thereby preventing the pier head 31 from separating from the clamping head 81 and causing tensioning failure. By fixing the clamping head 81 to the connecting plate 53 or the mounting plate 41 through bolts, it is convenient to disassemble and replace the clamping head assembly 8 later.

[0047] Throughout this specification, references to terms such as "one embodiment," "example," or "specific example" indicate that a specific feature, structure, material, or characteristic described in conjunction with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of these terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0048] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are merely illustrative of the principles of the present invention. Various changes and improvements may be made to the present invention without departing from the spirit and scope of the present invention, and such changes and improvements fall within the scope of the present invention as claimed.

Claims

1. A tensioning device for applying prestress to a concrete pole, comprising a base plate (1), a lower mold (2) fixed to the upper end of the base plate (1), a steel frame (3) provided in the mold cavity of the lower mold (2), and a plurality of steel bars uniformly distributed in the axial direction provided on the steel frame (3), characterized in that: Both ends of the steel bar are provided with pier heads (31), and the diameter of the pier heads (31) is larger than the diameter of the steel bar; The two ends of the steel bar frame (3) are respectively provided with a fixing mechanism (4) and a traction mechanism (5); the fixing mechanism (4) comprises a mounting plate (41) capable of sliding and adjusting along the axial direction of the steel bar, and a plurality of clamping assemblies (8) corresponding one to one with the pier heads (31) are provided on the mounting plate (41); the traction mechanism (5) comprises a supporting plate (51) capable of sliding and adjusting along the axial direction of the steel bar, and a cylinder (52) is provided on the supporting plate (51), and a connecting plate (53) is fixed on the driving shaft of the cylinder (52), and a plurality of clamping assemblies (8) corresponding one to one with the pier heads (31) are provided on the connecting plate (53); The clamp assembly (8) includes a clamp (81), a positioning hole (812) that cooperates with the pier head (31) is provided on the clamp (81), a clamping unit (82) is provided on both sides of the clamp (81), and a slidable clamping block (823) is provided in the clamping unit (82) to clamp the steel bar.

2. A tensioning device for applying prestress to a concrete pole according to claim 1, characterized in that: The clamping unit (82) includes a fixing frame (821) fixed on the clamping head (81), and a cylinder (822) is provided on the fixing frame (821) to drive the clamping block (823) to slide.

3. A tensioning device for applying prestress to a concrete pole according to claim 1 or 2, characterized in that: A through slot (813) is respectively formed on opposite sides of the clamping head (81), and the through slot (813) is communicated with the positioning hole (812); and the two clamping blocks (823) are slidably matched with the two through slots (813).

4. A tensioning device for applying prestress to a concrete pole according to claim 1 or 2, characterized in that: The clamping block (823) is provided with an arc surface that cooperates with the steel bar.

5. The tensioning device for applying prestress to a concrete pole according to claim 1, characterized in that: The chuck (81) is provided with a fixed shaft (811), and a threaded hole is provided at the end of the fixed shaft (811). A bolt passes through the mounting plate (41) or the connecting plate (53) and is screwed into the threaded hole to achieve the fixation of the fixed shaft (811) and the mounting plate (41) or the connecting plate (53).

6. A tensioning device for applying prestress to a concrete pole according to claim 1, characterized in that: The mounting plate (41) is slidably connected to the base plate (1), and the sliding direction is parallel to the axial direction of the steel bar. Two first fixing plates (12) are provided at the upper end of the base plate (1). A first screw rod (6) is rotatably connected between the two first fixing plates (12). The first screw rod (6) passes through the mounting plate (41) and is threadedly connected thereto.

7. A tensioning device for applying prestress to a concrete pole according to claim 6, characterized in that: The thread lead angle of the first screw rod (6) is smaller than the equivalent friction angle.

8. The tensioning device for applying prestress to a concrete pole according to claim 1, characterized in that: The support plate (51) is slidably connected to the bottom plate (1), and the sliding direction is parallel to the axial direction of the steel bar. Two second fixing plates (11) are provided at the upper end of the bottom plate (1). A second screw rod (7) is rotatably connected between the two second fixing plates (11). The second screw rod (7) passes through the support plate (51) and is threadedly connected thereto.

9. A tensioning device for applying prestress to a concrete pole according to claim 8, characterized in that: The thread lead angle of the second screw rod (7) is smaller than the equivalent friction angle.

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