JPS58160822A - Infrared water level meter - Google Patents

Abstract

PURPOSE:To measure water levels without installing wells, conduits, etc., by calculating the level of a liquid surface from the incident angle when the IR rays reflected from the liquid surface is received in a receiver and the distance between a transmitter and the receiver. CONSTITUTION:IR rays are emitted from an IR oscillator 19 in the direction of an arrow. The oscillator 19 is fixed to a shaft 20. The shaft 20 is supported by bearings 21, is fixed to a servocontrol motor 22, and revolves in the direction of the arrow thereby rotating the oscillator 19 in the same direction. The IR rays from the oscillator is changed in direction by said rotation and is reflected on the liquid surface. The voltage corresponding to the angle of revolutions is outputted from a terminal 24 by a potentiometer 23 indicating the revolving angle of the shaft 20. The output voltage of the potentiometer 23 indicating the rotating angle of the transmitter 19 is outputted from the terminal 24 and is converted to digital quantity with an A/D converter 25. An operating device 26 calculates the same and outputs the water level. The IR emitted from the oscillator 19 are reflected on the liquid surface, and is detected with a receiver 17, the output whereof is inputted to the operator 26 and latches the results of the calculation. The latched and held value is indicated on a level indicator.

Description

[Detailed description of the invention] (al Technical field of invention The present invention relates to an infrared water level needle that uses infrared rays.

(b) Conventional technology and problems There are many types of water level needles used to measure water levels in rivers, dams, etc.; On the other hand, there are pressure-type devices that are easy to install but have low accuracy and reliability.

FIG. 1 shows a conventional float-type water level needle using a well. In the same figure, the water level of the water surface 2 of the dam 1 is maintained at the same level as the water surface 5 of the well 4 through the water conduit 3'.A float 6 is balanced with a plow 9 having a pointer 8 via a thread 7. , the scale lO indicating the water level is read with the pointer 8. In such a configuration, installation of the well and installation of water pipes requires a great deal of expense, and a simple and low-cost water level gauge is desired.

(C) Object of the Invention In order to solve the above-mentioned problems, it is an object of the present invention to provide a new water level gauge that measures the water level using the angle of incidence of infrared rays on the liquid surface.

(d) Structure of the Invention According to the present invention, in a water level needle that measures the water level by measuring changes in the water level on the liquid surface using infrared rays, the incident angle with respect to the liquid surface is continuously adjusted at a constant period. The infrared rays are emitted from an infrared emitter while changing the infrared rays, and when the infrared rays reflected from the liquid surface are received by a receiver, the liquid level can be determined from the incident angle and the distance between the infrared emitter and the receiver. This is achieved by calculating and.

(e) Embodiments of the Invention The present invention will be explained below based on the principle diagram shown in FIG. 2 and the embodiments shown in FIGS. 3 and 4.

FIG. 2 is a diagram explaining the principle of a water level gauge using infrared rays. In the figure, the infrared transmitter 11 rotates in the direction of the arrow at a constant cycle. Therefore, the infrared light beams 12, 13, and 14 emitted at each hour are reflected by the liquid surface 15, and
A predetermined incident angle αl of infrared rays with respect to 5 (liquid level 0 of the incident light
angle with respect to the normal 16 at the point), it is received by the infrared receiver 17.

In the figure, the distance between the infrared transmitter 11 and the infrared receiver (hereinafter referred to as receiver) 17 is L, and when the position connecting the infrared transmitter 11 and receiver 17 is parallel to the liquid surface 15, the distance is L. Distance R between midpoint 18 and liquid level 1500 point
is represented by R=--tuα, where α=90°-α1.

Here, if you measure the distance to the water bottom 18 in advance, the water level HF1 H=D-R=D-Ttuα ・−−−−−−−−−−−
It is determined from (]).

FIG. 3 shows an infrared transmitter used in the present invention and an infrared transmitter that rotates the infrared light emitted from the transmitter at a constant cycle.

In FIG. 3, the infrared transmitter 19 is emitted in the direction of the arrow. The transmitter 19 is fixed to a shaft 20, which is supported by a bearing 21, and which is supported by a servo motor 22.
is fixed to and rotates in the direction of the arrow, causing the transmitter 19 to rotate in the same direction. As a result, the infrared rays III from the transmitter are reflected at the liquid surface 15 (shown in FIG. 2) by changing the angles of 12, 13, and 14, as shown in FIG.

The right end of the shaft 20 is provided with a potentiometer and a meter 23 that indicate the rotation angle of the shaft 200, and the potentiometer 23 outputs a voltage corresponding to the rotation angle from a terminal 24.

Figure 4 shows how to calculate equation (1) for displaying the liquid level by corresponding the output of the potentiometer to the output of the infrared receiver.
The water level calculation circuit is shown. In the figure, a potentiometer indicates the rotation angle of the infrared transmitter 19.

The output voltage of the meter 23 is output from the terminal 24, the output voltage is converted into a digital quantity by the A/D converter 25, and the calculator 26 calculates the digital quantity and outputs the water level shown in equation 1). There is. The infrared rays emitted from the infrared transmitter 19 are reflected by the liquid surface 15 (shown in FIG. 2) and sent to the receiver 1.
7 receives the light, and its output is input to the arithmetic unit 26 to read the arithmetic result. The latch holding value is the water level indicator 2'
7.

(1) Effects of the Invention According to the present invention, the water level can be measured without installing wells, water pipes, etc., which is economically advantageous.

[Brief explanation of drawings]

Figure 1 shows a conventional float type water level gauge using a well.
FIG. 2 shows a principle diagram of the present invention, FIG. 3 shows an embodiment of the invention showing infrared radiation, and FIG. 4 shows an embodiment of the invention for calculating water level. In the figure, 1 is the dam, 2 is the water pipe (or quasi-surface), 3 is the water pipe, 4 is the well, 5 is the water surface, 6 is the float, 7 is the thread,
8 is the pointer, 9Fi dial, ]0 scale, ]1 is the infrared rays, 12,
13.14 is the infrared light emitted, 15 is the liquid (or water surface), 16 is the normal, 17 is the 6 infrared receivers, 18 is the midpoint,
19 is an infrared transmitter, 20 is a shaft, 21 is a bearing, 2
2 is a servo motor, and 23 is a lid. 24 is a terminal, 25 is an A/D converter, 26 is a calculator, and 27 is an indicator. Akira 1 Figure 2 Figure Ryo 3 Figure

Claims (1)

[Claims] In a water level meter that measures the water level by measuring changes in the water level using infrared rays, the infrared rays are emitted from an infrared transmitter while continuously changing the angle of incidence on the liquid surface at a fixed period, and An infrared water level gauge, characterized in that the liquid level is calculated from an angle of incidence when a receiver receives wrinkle infrared rays reflected from a surface and a distance between the infrared transmitter and the receiver.