JPS6161027A - Measuring instrument for tension of wire body - Google Patents

Abstract

PURPOSE:To easily measure the tension of the gut of a racket, etc., by providing an incidence sensor and a detection sensor for an ultrasonic wave on a wire body at specific distance, and detecting the propagation speed of the ultrasonic wave. CONSTITUTION:Contact terminals 6 and 7 are provided on the wire body 1 such as a gut at the specific distance l. Further, the ultrasonic signal is inputted from an ultrasonic transmitter 4 to a contact terminal 6 through a incidence sensor 2. Further, its receive signal is inputted to an ultrasonic receiver 5 from the contact terminal 7 through a detection sensor 3. A ultrasonic wave transmitter 4, receiver 5, and a speed measuring instrument 10 are connected. Then, the ultrasonic wave is transmitted by the ultrasonic wave transmitter 4 and received by the receiver 5 through the wire body 1. The time from the transmission to the reception is measured to detect the speed of the ultrasonic wave signal. The speed is fast when the tension of the wire body is large and slow when small, so the tension of the wire body is measured easily and precisely with the ultrasonic wave signal.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention is applicable to the measurement of string tension on rackets for tennis, badminton, etc., or the measurement of tension during pulling and winding in spinning, electric wire, and cord factories. Furthermore, the present invention relates to a tension measuring device for striatal bodies that uses ultrasonic signals to measure the tension of lobes, wires, etc. in machines, structures, buildings, etc.

[Conventional technology]

Regarding the conventional measurement of tension in striatal bodies, for example, strings stretched on tennis rackets,
The object of measurement is the net tension, which includes the mesh size of the guts stretched vertically and horizontally, that is, blood pressure. However, regarding (2), although the tension at the time when the racket 1~ is stretched on the racket 1~ can be measured, even if the tension on the racket 1~ is relaxed due to the ball hit and the passage of time,
There was no way to measure the tension of each string after reaching such a state. Measurement of blood pressure in (2) can be performed using a measuring device 100 as shown in FIG.
applies a constant load to the racks h211, h11+, and guts 21 stretched on the racket frame 20 (
= The cut 210 surface pressure was measured.

(Problem to be solved) Conventionally, it was not possible to measure the tension of each filament fk (gut 21), and it was not possible to measure the tension of each filament fk (gut 21). This measuring method can only measure the surface pressure that occurs, and furthermore, after measuring the surface pressure, it causes a change in the tension in the striatum.

Therefore, the present invention was developed with the aim of providing a tension measurement system that makes it possible to measure the tension of each striatum and does not cause subsequent changes in tension due to the measurement. .

[Means for solving problems]

This invention solves the above-mentioned problems and easily measures the tension in each striatum. an ultrasonic signal incidence sensor mounted at intervals, and a detection sensor for detecting the ultrasonic signal propagated from the sensor to the striatum;
The measuring device was composed of an ultrasonic signal oscillator connected to the incident sensor, an ultrasonic signal receiver connected to the detection sensor, and a speed measuring device for measuring the speed of the ultrasonic signal.

〔Example〕

Below, preferred embodiments of the present invention will be described with reference to the drawings.

Reference numeral 1 in the drawings indicates a striated body such as a string, an electric wire, a cord, or a wire, and this striated body 1 is stretched over a predetermined distance. Two sensors 2 . The other sensor 3 is a detection sensor 3 that is connected to an ultrasonic signal receiver 5 and detects a signal propagating through the striatum 1 .

In FIG. 1, both sensors 2.3 are not attached directly to the strip 1, but via contact terminals 6.7. This contact terminal 6 (same as 7) is shown in Fig. 2(a).
As shown in (b) and (C), those that simply touch the striatum 1 (Fig. 2(a)) and those that sandwich the striatum 1 (Fig. 2(a))
b)), which passes through the striatum 1 (Fig. #12 (C)), etc., can be considered. Also, contact @terminal 6 (7)
It is also possible to use grease 8 and lip ring agent 9 between the wire and the striated body 1 to achieve close contact with the striated body 1 and facilitate the transmission of ultrasonic signals (see FIG. 3). Not only the contact terminal 6 (7) having the shape shown in Fig. 3, but also the contact terminal 6 (7) having the shape shown in Fig. 2 (a) and (b) Also used for The contact terminal 6 (7) may be made of any material that has a certain hardness and can be mechanically processed, such as acrylic resin, borisdyrene resin, polyacrylate-1 to tH1, polypropylene resin, or epoxy resin. Of course, it is also possible to process the vibrators of both sensors υ-2 and 3 into shapes as shown in FIGS. 2(a), (b), and (C) and attach them directly to the filament body 1.

Ultrasonic signal transmission, a quick measuring device 10 is attached to the receiver 4.5, and the measuring device 10 makes the ultrasonic signal enter the striatum 1 from the incident hinter 2 and detect it from the detection sensor, and the ultrasonic signal is detected by the detection sensor. Signal time! ! Measure t. Both Hinsa 2.
From the interval (and time difference [) of 3, the speed of sound C is calculated as follows.

Next, measure the tension of the tennis racket using a contact terminal 6.7 as shown in Figures 4 and 5, and set the distance (on one side (J!+)
The sound speed was measured when the tension was changed with r46m++i and the other (e2) r261m. The results were as shown in FIG. The graph marked 0 in Fig. 6 is the experimental result of the one shown in Fig. 4, and the graph marked Δ is the result of the experiment shown in Fig. 4. These are the experimental results shown in 1.

As is clear from this result, it was found that as the tension h (tension of the li%i strip 1) increases, the speed of sound also increases.

The speed measuring device 10 shown in FIG. 1 is equipped with a display device and an oscillograph 11. speed + t * constant 11f1
Of course, it is also possible to install a display using a microcomputer that calculates a predetermined gI value to 0 and immediately displays the tension value.

〔effect〕

As explained above, according to the present invention, there is provided an incident sensor for ultrasonic signals that is attached at regular intervals to the tm strip stretched over a predetermined distance, and
a detection sensor υ- for detecting the ultrasonic signal propagated from the to the striatum; an ultrasonic signal oscillator connected to the incident sensor; and an ultrasonic signal light unit connected to the detection sensor 9-. , a speed measuring device that measures the speed of the ultrasonic signal;
Not only is it possible to measure the tension in each striatum, but the measurement requires simply applying both sensors to the striatum, making it extremely easy to use! Fat). In addition, since there is no need to apply a load to the stretched striatum as in the conventional method, there is no impact on the striatum.

[Brief explanation of the drawing]

Fig. 1 shows a preferred embodiment of the present invention - 11 overall view, Fig. 2 (a) to C) is a perspective view showing eight examples of contact terminals, and Fig. 3 shows the relationship between the wire body and the contact terminal. The cross-sectional views of FIGS. 4 and 5 show examples in which different contact terminals are used and the spacing between each terminal is changed. i oblique? 52 and 6 are graphs showing the relationship between tension and sound velocity according to the examples shown in FIGS. 4 and 5, and FIG. 7 is a partial sectional view showing the conventional example. 1...Striatum, 2...Incidence sensor, 3...Detection sensor 9-. 4... Ultrasonic signal oscillator, 5... Ultrasonic signal receiver, 6.7... Contact terminal, 10... Speed measuring device.

Claims (1)

[Claims] 1. A sensor for the incidence of ultrasonic signals that is attached at regular intervals to the striatum stretched over a predetermined distance, and an ultrasonic signal propagated from the sensor to the striatum. It consists of a detection sensor for detecting, an ultrasonic signal oscillator connected to the incident sensor, an ultrasonic signal receiver connected to the detection sensor, and a speed measuring device for measuring the speed of the ultrasonic signal. Striatal tension measuring device. 2. The speed measuring device is configured to determine the speed of sound from the time it takes for the detection sensor to detect this signal after the signal is input from the incident sensor to the striatum and the distance between both sensors. A striatal body tension measuring device according to claim 1, characterized in that: