JPS6073311A - Ultrasonic water level measuring device - Google Patents

Abstract

PURPOSE:To measure an extensively variable water level at high accuracy, by holding an ultrasonic-wave transmitting and receiving apparatus available for vertical displacements at the specified distance from a water level. CONSTITUTION:At a jointing bracket 9 of a supporting strut 6 where ultrasonic- wave transmitting and receiving apparatus 2 and theremometer 10 are connected with a supporting body 4 through a connecting rod 5, the title apparatus 2 and the thermometer 10 are free to move up and down. The distance l between the apparatus 2 and a water level is held within a range; 2m<l<(2+L)m, where L represents natural numbers 1-10. An ultrasonic-wave pulse is applied to the water level 1 and the water level is obtained from transmission time of pulse returning from the water bottom 7 after reflection and corrected by the atmospheric temperature and sound velocity. As the distance between the apparatus 2 and water level 1 is kept within the constant range, measurement of extensively variable water level can be available with high accuracy.

Description

[Detailed description of the invention] Concerning a device for measuring water level.

The conventional ultrasonic water level measuring device for tuna has an ultrasonic transducer 2 mounted above the river water surface 1 in a house-like manner, emits ultrasonic pulses toward the water surface 2, and when the pulses propagate back by being reflected from the water bottom 7.
It has a structure that calculates the water level from lJl and the speed of sound (first
(see figure). This water level measurement device has a limited measuring range of U to 10 mK because there is a limit to the reflected energy of ultrasonic waves. However, since the water level in dams and the like usually fluctuates by 40 to 50 meters, this ultrasonic water level measuring device has the disadvantage that it cannot immediately measure the water level.

The inventor of the present invention conducted extensive research to obtain a device capable of measuring water levels that fluctuate widely, and as a result, installed an ultrasonic transducer so that it could be moved up and down, and maintained a constant width at all times between the ultrasonic transducer and the water surface. The present invention was completed based on the idea that it would be better to maintain the same.

That is, in the present invention, an ultrasonic transducer 2 and ten thermometers are installed above the water surface 1 so as to be movable in the vertical direction, and the distance to between the ultrasonic transducer 2 and the water surface l is always calculated using the following formula (%). %) (In the formula, L represents a natural number 7 from 1 to 10).

The ultrasonic transducer 2 used in the present invention is not particularly limited,
You can use what you normally use.

This ultrasonic transducer 2 is attached to a column 6 attached to a support 4 installed on the shore 3 via a connecting rod 5. Specifically, the column 6 of the VC has a length that is higher than the height of the shore 3 and reaches the water bottom (water level zero) 7, and this column 6 is provided with an opening for vertical movement. A mounting part 9 connected to the control part 8 is attached, and several of the ultrasonic transducers 2 are installed here facing toward the water surface. Alternatively, instead of using the column 6 and the mounting part 9, the five connecting rods can be mounted on the support body 4 and one vertically movable function e (with a mounting plate) can be used.
, I would like to install two ultrasound transducers for this interview.
, may be done.

The distance #Il between the ultrasonic transducer 2 and the water surface is as described above.
It is always maintained in the range of 2 m < to < (2 + L) m, but this is done by moving the water level up and down through the connection between the mounting part 91 and the column 6 under control from the control part 8 based on the sound of the water level change. Now.

Furthermore, since the propagation speed of sound waves changes depending on the temperature, the water level measurement must be corrected depending on the temperature. Therefore, it is necessary to attach the entire thermometer 10 to the mounting portion 9 (or connecting rod 5) VC.

The ultrasonic transducer 2 transmits an ultrasonic pulse to the water surface, and the water level is determined from the propagation time and sound speed of the pulse, which is reflected from the water bottom 7 and returned to the water, corrected by the air temperature. When using the device of the present invention, the water level can be determined by the following formula.

H= Do + n L (Co+αT) t/2(
In the formula, H is the water level, Do is the distance between the zero point of the water level gauge and the reference installation position of the transducer, n is an integer, L is the unit of movement of the ultrasonic transducer (a natural number up to 10), and the speed of sound at CotjO℃ (331 , 45 m/s) where α is the acoustic velocity coefficient (o , 607 n/s ・'c) T is the temperature (°C) and t is the round trip propagation time of the ultrasonic pulse (see) k) It has the following structure, and by using this sound, the following effects can be obtained.

(1) Because the distance between the ultrasonic transducer and the water surface is always maintained within a certain range, the water level measurement range of conventional devices is 0.
~10n1, but it has a wider range of 0~50m.

12) Conventional system @ generates ultrasonic pulses due to fluctuations in water level)
However, the measurement accuracy is extremely high because the device of the present invention can maintain the ultrasonic propagation distance within the range of ^1#k, regardless of fluctuations in the water level.

As described above, the device of the present invention has the advantage of being highly versatile compared to conventional devices. Note that the device of the present invention can be applied not only to water level measurement VC but also to various distance measurement rectangles such as snow depth measurement.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing an embodiment of a conventional device, and FIG. 2 is a schematic MTF diagram showing an embodiment of the present invention device. In the figure, ] is the water surface, 2 is the ultrasonic transducer, 3 is the shore, 4 is the support, 6 is the column, 7 is the bottom of the water, 9 is the mounting part, and 10 is the thermometer? show. Patent applicant: Sumitomo Electric Industries, Ltd. Patent attorney: Shibu Mitsuishi (and one other person)

Claims (1)

[Claims] Move the ultrasonic transducer and thermometer vertically above the water surface! ! ! The distance between the ultrasonic transducer and the water surface should be maintained within the range expressed by the following formula (%) (in the formula, L represents a natural number from 1 to 10). Ultrasonic water level measuring device with all the features to make it.