JPH07294350A - Tension meter - Google Patents

Abstract

PURPOSE:To provide a tension meter which has good detection sensitivity, can accurately measure even low tension and is hardly confined in use in space point of view. CONSTITUTION:In the middle of a length of tightening tool for withdrawing with a turnbuckle 2 a pair of bolts 3 facing to each other having connection tools 4, a.metal ring 1 is fixed in series on which ring a strain gauge 5 is pasted. Thus, the ring 1 bends relatively large with low tension and the resistance variation of the strain gauge 5 becomes large so that detection sensitivity is raised. Since the tightening tool is combined in one, measurement is available even with small distance between the two points connecting the connection tools 4 at the both ends.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tensiometer which is particularly convenient for measuring the tension applied between two points.

[0002]

2. Description of the Related Art In a conventional strain gauge type tensiometer, a strain gauge is attached to the outer periphery of a metal rod, and both ends of this rod are gripped by chucks or the like to apply tension to the rod.

[0003]

Since the elongation of the tension ratio of the metal rod is small, if the measured tension is low, the resistance change of the strain gauge is small and the detection accuracy is poor.

Further, if the distance between the two points to which the tension is applied is short (for example, about 20 to 30 cm), the tension meter cannot be set between the two points due to space limitations, and the measurement itself becomes impossible. There is also.

An object of the present invention is to eliminate these problems.

[0006]

In order to solve the above-mentioned problems, the tensiometer of the present invention has a metal ring connected in series in the longitudinal direction of a tightening tool which pulls a pair of bolts with a connecting tool facing each other with a turnbuckle. The strain gauge is attached to the ring that receives the tensile force when the bolt is attached and pulled.

The metal ring may be interposed either in the middle of the turnbuckle or in the middle of either one of the bolts.

[0008]

As described above, the elongation of the tension ratio of the metal rod is small, but if the metal ring is a low tension, the metal rod is relatively largely bent. Therefore, the strain gauge attached to this ring has the same tension. Greater than when added to a metal rod. Therefore, the change in resistance of the gauge also increases, and the detection sensitivity increases.

Moreover, in this structure, when the turnbuckle is tightened, the rattling of the bolts stops, so that there is no measurement error due to the rattling of the connection portion. Therefore, highly accurate measurement can be performed even when a low tension is applied.

Since the tightening tool is integrated,
It does not require a chuck for connection and can measure even if the distance between two points is short.

[0011]

EXAMPLE An example of the tensiometer of the present invention is shown in FIGS. In the figure, 1 is a metal ring for measuring tension, 2 is a turnbuckle, and 3 is a bolt with a locking part screwed to both ends of the turnbuckle.

The bolt 3 constitutes a tightening tool in combination with the turnbuckle 2, and has a connecting tool 4 for connecting to another member at the end portion on the side opposite to the screw-in side. The connecting tool 4 is preferably hooks as shown in FIG. 1 or eye fittings as shown in FIG. 2 in consideration of ease of manufacturing and cost, but the connecting tool 4 is not limited to this.

The ring 1 is provided either in the longitudinal direction of one of the bolts 3 as shown in FIG. 1 or in the longitudinal direction of the turnbuckle as shown in FIG. When the pair of bolts 3 and 3 connected to another member are pulled together by the turnbuckle 2, the ring is pulled left and right to bend regardless of the position shown in FIG. 1 or 2.

Reference numeral 5 is a strain gauge attached to the surface of the ring 1. When the ring 1 bends, the gauge is distorted and the electrical resistance of the gauge changes, and the applied tension can be obtained from the change in the output voltage.

[0015]

As described above, the tensiometer of the present invention is
Since the metal ring is bent and the output voltage of the strain gauge attached to this ring is measured, high detection sensitivity is obtained even when low tension is applied, and measurement accuracy is improved.

Since the tightening tool is integrated,
Even if the distance between the two points is short, the measurement can be performed without any trouble.

Note that the tensiometer of the present invention can be expected to have a particularly great effect when it is used for tightening while controlling the tightening force, for example, for adjusting the tension of the overhead wire of an electric wire or the like.

[Brief description of drawings]

FIG. 1 is a front view showing an example of a tensiometer of the present invention.

FIG. 2 is a front view of another embodiment.

[Explanation of symbols]

 1 Metal ring 2 Turnbuckle 3 Bolt with connector 4 Connector 5 Strain gauge

Claims (1)

[Claims] 1. A metal ring is attached in series midway in the longitudinal direction of a tightening tool that pulls a pair of opposed bolts with a turnbuckle, and a strain gauge is attached to the ring that receives a tensile force when pulling the bolt. Tensiometer.