JPH04198723A - Water level gauge - Google Patents

Abstract

PURPOSE:To obtain a simple and small water level gauge easy to maintain by incorporating a permanent magnet in a float lifted or lowered in response to the change of the water level, detecting the change of the magnetic field with a magnetometer, and converting the detected value into the water level value with a conversion processing device. CONSTITUTION:A gap is provided between the lower end section of a breakwater tube 7 erected in a water tank and the bottom face of the water tank, a small hole is provided, and the water level in the the tube 7 is stable. A float 4 in the tube 7 is lifted or lowered by the change of the water level, and the magnetic field by a built-in strong permanent magnet is also lifted or lowered. The change of the magnetic field is detected by a magnetometer 3, and the detected value is converted into the water level value by a conversion processing device to detect the water level. The float 4 incorporated with the permanent magnet is merely floated on the water surface, a water level gauge can be miniaturized, installation is simplified, and maintenance is facilitated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a water level gauge that detects the position of a water surface or liquid level in an aquarium or the like.

[Prior art 1] Fig. 3 and Fig. 4 show a conventional water level gauge.
95 are connected, and the wire rope 95 is connected to the drum 98.
A counterweight 99 is attached to the other end. The shaft of the drum 98 is connected to a water level detector 93.

As the water level inside the breakwater pipe 7 rises and falls, the float 94 moves up and down, the drum 98 rotates via the wire row 195, and the water level detector 93 detects the water level based on its rotation angle. The signal is sent from transmitter 96 to receiver 90.

[Problems to be Solved by the Invention] Although the conventional water level gauge is as described above, it requires mechanical force to apply tension to the wire row 195 using the float 94 and the counterweight 99 to rotate the drum 98. , a fairly large float 94 is required, the diameter of the breakwater tube 7 is approximately 25 cm, and its support structure must also be made sturdy.

In addition, since the detection method is mechanical, there is a problem that maintenance is time-consuming.

This invention was made to solve these problems, and the purpose is to obtain a water level gauge that has a relatively small float, a small breakwater, a simple support structure, and requires no maintenance. do.

[Means for Solving the Problems] A water level gauge according to the present invention includes a float that has a built-in permanent magnet and is floated on the water surface in a breakwater pipe, and a magnetic field formed by the permanent magnet that is built in the float. It consists of a magnetometer installed to detect the strength of the magnetic field, and a conversion processing device that converts the strength of the magnetic field detected by the magnetometer into a water level value.

[Function] The permanent magnet built into the float of the water level gauge according to the present invention forms a magnetic field around it, and the installed magnetometer detects the strength of this magnetic field. As the water level changes, the float rises and falls accordingly, and the permanent magnet inside the float also rises and falls, changing the strength of the magnetic field where the magnetometer is placed. The water level is detected by detecting changes in the strength of this magnetic field with a magnetometer and converting the detected value into a water level value with a conversion processing device.

[Example] Hereinafter, an example of the present invention will be described with reference to the drawings. 1st
1 and 2 show a water level meter according to an embodiment of the present invention, FIG. 1 is a side cross-sectional view, and FIG. 2 is a block diagram of a Hall magnetometer. Float with built-in magnet, 7 is a wavebreak tube, 33 is a Hall element, 3
7 is an indicator meter.

In a tank for a water treatment plant or the like where the water surface is rippled due to water injection, etc., it is necessary to calm down the water level before detection, so a breakwater pipe 7 is provided and the float 4 is placed inside it. A strongly magnetized permanent magnet is built into the float 4. The breakwater tube 7 is attached to the wall of the aquarium or the like, and the magnetometer 3 is installed on the top of the breakwater tube 7.

The magnetometer 3 includes a magnetometer that detects a change in magnetic flux with a magnetic flux detection coil and amplifies it to give an indication, a fluxgate magnetometer (external input type magnetic modulator magnetometer), a magnetometer that uses a Hall element, There are SQU ID magnetometers, etc., but the second
The figure shows a block diagram of a magnetometer using a Hall element.

Next, the operation will be explained. In FIG. 1, there is a gap between the lower end of the breakwater pipe 7 installed upright in the water tank, etc., and a small hole etc., between the bottom end of the breakwater pipe 7 and the bottom of the water tank.
The water level in the tank is the average water level in the tank after the effects of waves, etc. have been removed and the water level has calmed down. Float 4 floating on the water surface inside the breakwater pipe 7
rises and falls as the water surface inside the breakwater tube 7 rises and falls. Since a strongly magnetized permanent magnet is built into the float 4, a magnetic field is formed around the float 4 by this permanent magnet. As the float 4 moves up and down, this magnetic field also rises and falls and changes. At the position of the magnetometer 3 installed above, as the water level rises and the float 4 rises, the magnetic field becomes stronger, and as the water level becomes lower and the float 4 descends, the magnetic field becomes weaker. The water level can be detected by detecting this change in the magnetic field with the magnetometer 3 and converting the detected magnetic force value into a water level value with a conversion processing device (not shown).

There are various kinds of magnetometers 3 mentioned above, but the principle block diagram of the Hall magnetometer is shown in Figure 2.The magnetic field generated by the permanent magnet in the float 4 in Figure 1 is in the direction of the arrow in Figure 2. When the Hall element 33 is set at 1 and a constant current is passed from side to side of the Hall element 33 by the AC constant current generator 34, a voltage V proportional to the strength of the magnetic field is generated between the end faces of the Hall element 33. Occur. This voltage V is amplified by an amplifier 35, synchronously rectified by a synchronous rectifier 36, and converted, so that the indicator meter 37 can indicate the strength of the magnetic field. As for the strength of the magnetic field, as shown in Figure 1, when the water level rises and the float 4 rises, the magnetic field becomes stronger, and when the water level becomes lower and the float 4 falls, the magnetic field becomes weaker, and there is a relationship between the height of the water level and the strength of the magnetic field. 1, it is possible to detect the strength of the magnetic field and convert it to determine the height of the water level.

This water level gauge uses a float 4 with a built-in permanent magnet.
Because it only needs to float on the water surface, it can be made small, the breakwater tube 7 is also small, and installation is easy.
There is no mechanical connection and g! There is no scratching, so maintenance is easy.

In the above explanation, water, water level, etc. refer to liquid.

Of course, it may be read as liquid level, etc.

[Effects of the Invention] As described above, according to the present invention, the float containing a permanent magnet needs only to float on the water surface, so it can be made small, and the breakwater tube is also small, making it easy to install.
Since there is no mechanical connection or friction, a water level gauge that is easy to maintain is obtained.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view of a water level meter according to an embodiment of the present invention, and FIG. 2 is a block diagram of a magnetometer using a Hall element. FIG. 3 is a side sectional view of a conventional water level gauge, and FIG. 4 is a diagram showing a conventional detection mechanism. In the figure, 3 is a magnetometer, 4 is a float containing a permanent magnet, 7 is a wavebreak tube, and 33 is a Hall element. In addition, in the figures, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] A float that has a built-in permanent magnet and can be floated up and down on the water surface inside a breakwater pipe, a magnetometer installed to detect the strength of the magnetic field formed by the permanent magnet built into this float, and this magnetic force. A water level meter that consists of a conversion processing device that converts the strength of the magnetic field detected by the meter into a water level value.