JPH08152369A - Method and device for measuring tension of wire rod - Google Patents

Abstract

PURPOSE: To measure the tension of a wire rod relatively simply and accurately even for the wire rod, whose Young's modulus is unknown, or the tensioned wire rod. CONSTITUTION: Supporting-point members 2 and 4 are provided at the center and both ends of a main body 1 and engaged with a wire rod 9. The supporting- point members 2 and 4 at the center or both ends are made mobile, and the wire rod 9 is moved in the direction intersecting the axis at a right angle. When the wire rod 9 is deformed by specified amount, the reaction force acting on the supporting-point members 2 and 4 is measured, and the tension of the wire rod 9 is obtained from the reaction force.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tension measuring method and apparatus for measuring the tension of wire materials such as wire cables and rods used in a tension structure.

[0002]

2. Description of the Related Art In recent years, a building in which an outer wall or a roof is constructed by supporting a plate material such as glass by a tension structure using a wire material such as a wire cable or a rod has been put into practical use. In constructing such a tension structure, it is necessary to adjust the tension applied to the wire to a target value, and for that purpose, it is necessary to accurately measure the applied tension.

A conventional method for measuring the tension of a wire rod is to measure the torque value of a turnbuckle portion at the end of the wire rod, which is used when applying tension, and convert the tension value from that value. However, no special device is required, but there is a problem that the measurement error is large.

There is also a method in which the tension is converted from the frequency of the wire by shaking the wire, but there is the problem that the measurement error is large.

There is also a method of using a weight to measure the amount of displacement generated by applying a load perpendicular to the wire and converting the tension from that value. However, the weight that displaces the wire is extremely large. There is a problem that workability is poor considering that the work is heavy, narrow and expensive.

Further, there is also a method in which a strain gauge is attached to a wire before tension is applied, the strain when the tension is introduced is measured, and the value is converted into the tension. Since the Young's modulus of the wire needs to be known, and it cannot be measured unless a strain gauge is attached without tension, it cannot be applied to a wire of unknown Young's modulus. Further, there is a problem that the tension already applied cannot be measured, such as during maintenance of the tension structure.

Therefore, at present, there is no measuring method which has both measurement error and workability.

[0008]

DISCLOSURE OF THE INVENTION The present invention solves the problems of the above-mentioned prior art, and is capable of accurately measuring the tension of a wire whose Young's modulus is unknown or a wire to which tension has already been applied. The purpose is to provide the device.

[0009]

According to the present invention, a part of a wire rod to which tension is applied is supported by three fulcrums, the wire rod is deformed by a certain amount in the direction orthogonal to the axis between the three fulcrums, and is deformed by a certain amount. A tension measuring method of a wire and a device for measuring the tension of the wire from a reaction force acting on a fulcrum at the time.

A description will be given below with reference to the drawings. Figure 1
FIG. 2 is a perspective view of the tension measuring device of the present invention, and FIG. 2 is an explanatory diagram for explaining the operation of the present invention. In the figure, 1 is a main body, 2,
4 is a fulcrum member, 5 is a measuring part, and 9 is a wire.

As shown in the figure, the main body 1 has an elongated shape and has fulcrum members 4 projecting in the direction orthogonal to the axis at both ends thereof, and projecting in the same direction as the fulcrum member 4 in the center. It has a fulcrum member 2. The tip of the fulcrum member 4 has a concave shape so that the abutting wire rod does not come off when the wire rod 9 is deformed. On the other hand, in the vicinity of the tip of the fulcrum member 2, a U-shaped cut 3 with which the wire is engaged is provided.

Reference numeral 8 denotes a bolt which is screwed into the main body 1, and is rotated so as to move relative to the main body in the direction of the arrow. The fulcrum member 4 is rotatably engaged with the bolt 8, and by rotating the bolt, the fulcrum member 4 moves in the direction of the arrow relative to the main body. At that time, since the fulcrum member 4 is rotatably engaged with the bolt 8, when the wire member exerts a rotation restraining force on the fulcrum member, the fulcrum member 4 is rotated even if the bolt is rotated.
Does not rotate. Thus, the bolt 8 is rotated and the tip of the support member 4 is moved by a certain amount D with respect to the main body.

On the other hand, the fulcrum member 2 is fixed to the main body and does not move relative to the main body unlike the fulcrum member 4. A load cell 5 is connected to the fulcrum member 2, and when the fulcrum member 4 moves by a certain amount, a reaction force F applied to the fulcrum member 4 (a reaction force applied to the fulcrum member 2 is 2F).
Can be measured. Instead of connecting the load cell to the fulcrum member 2, a load cell may be connected to the fulcrum member 4 and the reaction force applied to the fulcrum member 4 may be measured.

The movement of the fulcrum member 4 causes the wire 9 to be deformed at an angle A between the fulcrum member 4 and the fulcrum member 2.
The reaction force F applied to the fulcrum member 4 due to this deformation is measured. The tension T of the wire 9 is calculated from T = F / sinA.

The length D between the fulcrum members 4 and 2 and the amount of movement D of the fulcrum member 4 are such that the deformation angle A of the wire formed between the fulcrum member 4 and the fulcrum member 2 is 1/30 to 1/10. It is desirable to select it in the range of radians. This angle is 1
If it is less than / 30 radians, the measurement accuracy becomes too low, which is not preferable, and if it exceeds 1/10 radians, the portion contacting the fulcrum of the wire may be greatly bent and the wire may be damaged, which is not preferable. Further, considering the ease of handling, the length between the fulcrum members 4, 4 is preferably about 200 to 800 mm when the wire tension is about 1 to 5 tons.

As a material for the main body and the like, a metal such as stainless steel, ordinary steel or aluminum is used in terms of strength, and aluminum is preferable for the main body in view of easy handling.

Incidentally, instead of moving the fulcrum members 4 and 4 at both ends, the fulcrum members 4 and 4 at both ends are fixed and the fulcrum member 2 at the center is moved, and the tension of the wire is measured in the same manner. Good.

Further, instead of moving the fulcrum members 4, 4, one fulcrum member 4 and the central fulcrum member are fixed, and the other fulcrum member 2 is moved, so that the attractive force of the wire can be similarly measured.

Further, the positions at which the fulcrum member 2 is provided do not have to be at equal positions to the fulcrum members 4 and 4. In that case, the reaction force F _A acting on one fulcrum member 4, the reaction force F _B acting on the other fulcrum member 4, and the reaction force F ₂ acting on the fulcrum member 2 are F ₂ = F _A + F _B It becomes a relationship. Reaction force F
Assuming that the angles of deformation of the wire by the fulcrum members 4 and 4 on which _A and F _B are acting are A and B, respectively, the tension T of the wire is T
= F _A / sin _A , T = F _B / sin _B, and T can be obtained by measuring F _A or F _B.

As the wire rod 9, a wire rope, a normal steel rod or the like is used.

Although not shown in the drawing, an arithmetic unit is mounted on the main body, and the arithmetic unit is electrically connected to the load cell 5. The calculation unit obtains the tension of the wire rod from the reaction force measured by the load cell 5 according to the above calculation formula. The calculation unit is electrically connected to the transmission unit 6 attached to the main body, and transmits the tension data obtained by the calculation unit to the information control unit isolated by radio. The energy required for these calculations and data transmission is covered by the battery mounted on the main body.

In measuring the tension of the wire rod, the fulcrum members 2, 4 of the tension measuring device are attached to the wire rod 9 to which the tension is applied.
4 is engaged, the bolts 8, 8 are rotated, and the fulcrum members 4, 4 are moved by D. As a result, the wire rod becomes the fulcrum members 2, 4
In the meantime, the angle is changed by A from the original state. This tension is
It does not necessarily have to be the final one, and may be larger or smaller than the final one.

When it is desired to set the tension applied to each wire rod as a target value for a plurality of wire rods as in the case of construction,
First, a tension smaller than the target value is applied to the wire. Next, a tension measuring device is attached to each wire, the bolts 8 and 8 are rotated, and the fulcrum members 4 and 4 are moved by D. D is set to the same value when the target value of the tension applied to each wire is the same, and when the target value of the tension applied to each wire is different, it is calculated according to the above formula. Value The data of the tension applied to each wire in this state is transmitted from each transmitting unit 6 to the information control unit separated by radio.

Then, the tension applied to each wire is increased by a turnbuckle or the like, and the information control section monitors the tension data transmitted from each transmission section 6, and when it reaches a target value. The increase in tension applied to the wire is stopped. Thus, the target tension is applied to each wire. Next, the bolt 8 of the tension measuring device attached to each wire is rotated in the opposite direction to bring the tip of the fulcrum member 4 closer to the main body 1 to reduce the reaction force acting on the fulcrum members 2 and 4 and to measure the tension measuring device. Remove.

[0025]

According to the present invention, the tension can be measured relatively easily and accurately even for a wire whose Young's modulus is unknown or a wire to which tension has already been applied. Therefore, for example, even in maintenance such as tension inspection after construction of the tension structure, the tension can be measured more easily than before.

In particular, when the main body is provided with a transmitter for wirelessly transmitting the tension data to the isolated information control unit, since there is no cord between the measuring device and the information control unit, the tension measuring device is attached and detached. And the movement work becomes easy.

[Brief description of drawings]

FIG. 1 is a perspective view of a tension measuring device of the present invention.

FIG. 2 is an explanatory view explaining the operation of the present invention.

[Explanation of symbols]

 1: body 2, 4: fulcrum member 5: load cell 6: transmitter 9: wire rod

Claims (4)

[Claims] 1. A reaction force acting on a fulcrum when a certain amount of the wire rod to which tension is applied is supported by three fulcrums, the wire rod is deformed by a certain amount in the direction orthogonal to the axis between the three fulcrums, and the certain amount is deformed. A method of measuring the tension of a wire by measuring the tension of the wire. 2. An elongated main body, a fulcrum member that is provided at the center and both ends of the main body and that engages with the wire rod to deform the wire rod by a certain amount in a direction orthogonal to the axis, and a fulcrum member when the wire rod is deformed by a certain amount. A wire rod tension measuring device comprising a measuring unit that measures a reaction force acting and obtains the tension of the wire rod from the reaction force. 3. The tension measuring device according to claim 2, wherein the main body is provided with a transmitting unit for wirelessly transmitting the tension data of the wire rod obtained by the measuring unit. 4. A wire rod, wherein the tension measuring device according to claim 3 is attached to a plurality of wire rods, and information about the tensions of the plurality of wire rods is wirelessly sent to an information control unit to measure the tensions of the plurality of wire rods at the same time. Tension measurement method.