JPH055938U - Wedge stopper for pretensioning grip - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a wedge stopper for a pretensioning grip, which is easy to remove the bound wedge and has excellent durability. [Structure] A thin metal wire is spirally wound, and both ends of this spiral material are connected to each other to form a ring having a predetermined diameter as shown in the figure. Fit and bundle the wedges 1. Since such a wedge stopper is in a state in which the coil spring is looped, it is rich in flexibility and elasticity, and the wedge can be easily put on and taken off. Further, since it is made of metal, it has excellent heat resistance, high breaking strength, and long life.

Description

[Detailed description of the device]

[0001]

[Industrial application]

 The present invention relates to a wedge stopper of a pretensioning grip used for fixing a PC steel strand.

[0002]

[Prior Art]

 As shown in FIG. 2, the pretensioning grip is composed of a wedge 1 divided into 2 to 4 pieces in the circumferential direction, a female cone 2 and a wedge stopper 3 for binding the wedges. The squeeze grip is made by passing a PC steel strand through a female cone 2 received by a bearing plate (not shown) and driving a wedge 1 between the female cone and the PC steel strand to perform tensioning work. Fix it. Since this grip is used repeatedly, check the wear condition of the ridges of the teeth 4 (see Fig. 3) of the wedge 1 that grips the wire from the PC steel each time it is used, and remove slag, dust, etc. from the valleys between teeth It must be removed to prevent a slip accident due to insufficient biting into the PC steel wire.

Therefore, the wedge stopper 3 is required to have elasticity so that the wedge 1 can be easily removed. In addition, since the pretensioning grip is exposed to steam of about 60 ° C during use, the wedge stopper is required to have excellent heat resistance. Furthermore, since it is a product that is used repeatedly, it must also have a service life against deformation and breakage.

On the other hand, the conventionally used wedge stopper is a metal ring having a simple shape in which a rubber ring or a thin wire rod is formed into an annular shape.

[0005]

[Problems to be solved by the device]

 A rubber ring wedge stopper has good stretchability but poor heat resistance, so it breaks after being used several times. On the other hand, a metal ring with a simple shape has excellent heat resistance, but is inferior in elasticity, and causes permanent deformation after being used several times. Also, it is difficult to work due to poor elasticity.

Therefore, the present invention intends to provide a wedge stopper in which only the features of the former two are utilized.

[0007]

[Means for Solving the Problems]

 The wedge stopper of the present invention comprises a thin metal wire spirally wound, and both ends of the wire are connected to each other to form a ring having a self-elastic restoring function of a predetermined diameter. Then, the divided wedges are bound together.

[0008]

[Action]

 Since it is made of metal wire, it has excellent heat resistance and breaking strength. In addition, since a thin metal wire is spirally wound and formed into a loop, it is highly stretchable and flexible, has improved resistance to repeated deformation, and the workability of binding and unbinding the wedge is also rubber. It is not inferior to the

[0009]

【Example】

 FIG. 1 shows an example of the wedge stopper of the present invention. This wedge stopper 3 is made by spirally winding a thin metal wire used as a spring material and further joining both ends of this spiral material to each other. It is sized to function as a tying band.

The metal wire used for the wedge stopper is preferably a spring steel wire having a plated surface or a spring wire made of a copper-based material in view of corrosion resistance. Further, although welding or the like is preferable for the connection of both ends for making the spiral material into a ring, mechanical connection using a joint may be used as long as it does not hinder the attachment to the wedge.

Since this wedge stopper is, so to speak, a coil spring formed into a ring, it is rich in flexibility and stretchability, and is excellent in durability and heat resistance.

[0012] Table 1 shows a comparison result regarding the life of the conventional product. In this way, the product of the present invention has an extremely longer life than the conventional product. In addition, workability is comparable to conventional rubber rings.

[0013]

[Table 1]

[0014]

[Effect of the device]

 As described above, since the wedge stopper of the present invention uses a spirally wound metal wire as a loop, it can satisfy all the required characteristics and is effective in improving workability and life thereof.

[Brief description of drawings]

FIG. 1 is a perspective view showing an example of a wedge stopper of the present invention.

FIG. 2 is a sectional view of a pretensioning grip.

FIG. 3 is a diagram showing details of a wedge.

[Explanation of symbols]

 1 wedge 2 female cone 3 wedge stopper 4 wedge teeth

Claims (1)

[Claims for utility model registration] [Claim 1] A thin metal wire is spirally wound, and both ends of the wire are connected to each other to form a ring having a self-elastic restoring function of a predetermined diameter. A wedge stopper for a pretensioning grip, which is configured to be attached to the outer periphery of a wedge of a pretensioning grip that is divided into a plurality of pieces in the circumferential direction as a stopper and to bind the wedge together.