JP2001041804A - Liquid-level sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a float-type liquid level sensor which stably measures the liquid level of a waste liquid process tank wherein the material value of an aqueous solution which affects sediment in the aqueous solution, presence of suspended matter, and precision of PH value and measurement value changes variously. SOLUTION: A float 4 for measuring a liquid-level data, a pulley part 5 for taking up the float, a taking up spring 6, and a rotary position sensor 8, are provided. Ventilation between a front part and a rear part is shielded, for environment resistance, while the pulley part for taking up float and the rotary position sensor 8 are directly connected, for a simple liquid-sensor.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention seeks to measure a liquid level condition at an installation position from time to time by using a liquid level transmission equipment, particularly a liquid level sensor installed in a specific tank, and to use the data from a remote place. It is related to the equipment that performs.

[0002]

2. Description of the Related Art Conventionally, when using such liquid level data at a remote place, measured values of some environmental sensors, for example, capacitance, pressure, and optical sensors, are converted into electrical data and converted. The data was transmitted via a wireless device or by wire to try to use it at a remote location. Such facilities are often used particularly in places where environmental conditions are poor, such as tanks for treating various kinds of waste liquids. However, in such a waste liquid treatment tank, the precipitates, suspended solids, and PH values in the aqueous solution also change variously depending on the treatment chemicals and the like corresponding to the object to be treated. In addition, there have been problems such as physical property values of the aqueous solution that affect the accuracy of the measurement values of the various sensors, for example, changes in the dielectric constant, dirt, and odor. In addition, even in the case of the float type in which these physical property values are not used for measurement, there is a possibility that suspended matter may adhere to the float and adversely affect the measurement accuracy.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and minimizes the components installed in places where the environmental conditions are poor, for example, various waste liquid treatment tanks. Moreover, it was necessary to optimize the materials used. In addition, it is necessary to improve the durability and reliability of components such as electronic components which are particularly susceptible to contamination due to passage of contaminants such as vapor due to air permeability and water permeability with the tank side.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and has been described in view of the above circumstances. Constructed to enhance acid and alkali resistance and corrosion resistance. In addition, the durability and reliability of the other components are improved by blocking the air permeability with the structure of the liquid level sensor itself.

Further, according to the present invention, since the shape of the float is reduced from the upper part of the draft surface to the lower part in the state of use to reduce the cross-sectional area, the adhesion of floating substances is reduced and the measurement accuracy is improved. Has improved. Further, by providing a device for preventing a mechanical connection part of the hoisting pulley portion and the float from falling off from the hoisting pulley, safety during maintenance and inspection and reliability during use are improved.

[0006]

FIG. 1 is a block diagram showing an embodiment of the present invention.
It will be described based on. FIG. 1 shows an embodiment of the present invention. This figure shows a cross section of the present liquid level sensor 3 mounted inside a control panel 2 installed on the upper part of the tank 1. Such a waste liquid tank is usually installed in a place where environmental conditions are poor, such as outdoors, so when it is necessary to control the liquid level, it is waterproof for control parts such as a board.
It is particularly important to consider dust and heat resistance. That is, it is desired that the ventilation of the control panel 2 and the waste liquid tank and the external environment be shut off.

Next, the configuration of the liquid level sensor 3 will be described. The liquid level sensor 3 includes a float 4 in the tank, which moves up and down following a change in the liquid level in the tank, a hoisting pulley 5 mechanically connected to the float 4, and a hoisting pulley 5 A hoist spring 6 for hoisting in response to the fluctuation, a bearing part 7 for supporting the rotating shaft of the hoisting pulley 5 to ensure smooth rotation, and a detection sensor 8 for detecting the rotational position of the rotating shaft of the hoisting pulley 5 It is composed of

[0008] The float 4 is in the waste liquor to be treated and is made of a resin such as vinyl chloride, polypropylene and polyethylene in order to increase its acid, base and corrosion resistance. Also, in order to prevent the adhesion of suspended solids in the waste liquid and increase the measurement accuracy, the cross-sectional area is reduced from a slightly upper part near the liquid surface to a lower part.

The hoisting pulley portion 5 mechanically connected to the float 4 is usually made of stainless steel wire.
In many cases, it is installed directly above the float 4 and when installed inside the control panel 2, it becomes impossible to shut off the ventilation between the control panel 2, the waste liquid tank and the external environment. Therefore, it is installed just above the float 4 and outside the control panel 2.

[0010] Since the winding spring 6 is mostly made of metal such as stainless steel or spring steel, there is a problem in corrosion resistance and acid resistance. Further, since the detection sensor 8 for detecting the rotational position of the rotating shaft of the hoisting pulley unit 5 and the other electronic components are required to be dust-proof and heat-resistant in addition to the above-mentioned problems, it is preferable to install them inside the control panel 2. Is desirable. For this reason, the bearing part 7 is configured to incorporate a sealed bearing and another independent seal for the purpose of blocking ventilation between the hoisting pulley part mechanically connected to the float in the tank and other components. I have.

Further, by directly connecting the hoisting pulley 5 to the hoisting spring 6 and a sensor 8 for detecting the rotational position of the hoisting spring 5, the measurement accuracy is improved while having a simple configuration. Specifically, the detection sensor 8 is a potentiometer or a digital output single-rotation type or multi-rotation type encoder.

Another embodiment of the present invention will be listed. FIG. 2 is a diagram showing another embodiment of the present invention. This configuration further increases the problem of blocking the ventilation between the hoisting pulley 7 mechanically connected to the float in the tank and other components. That is, the use of the magnet coupling in place of the mechanical seal of the bearing portion 7 in FIG.

Another embodiment of the present invention will be listed. FIG. 3 is a diagram showing still another embodiment of the present invention. The pulley portion shown in FIG. 1 is incorporated in the liquid level sensor 3, and a pulley for changing the direction of the mechanical connection part 11 with the float 4 is added to rotate the mounting direction in FIG. 1 by 90 degrees. . In the case of such a mounting, since there is a high possibility that the mechanical connecting component 11 comes off the hoisting pulley portion 7,
It is desirable that the fall-off preventing device 10 has a structure as shown in FIG.

The liquid level sensor according to the present invention is not limited to the electric transmission type, but may be an ordinary on-site indicating liquid level sensor.

[0015]

According to the present invention, there is provided a waste liquid treatment tank in which the presence of precipitates and suspended matter in an aqueous solution, and the physical properties of the aqueous solution which affect the accuracy of the PH value and the measured value are variously changed. A float type liquid level sensor capable of stably measuring the liquid level can be provided. Also, the durability and reliability of the parts used can be improved.

[0016]

[Brief description of the drawings]

FIG. 1 is a diagram showing one embodiment of the present invention.

FIG. 2 is a diagram showing another embodiment of the present invention.

FIG. 3 is a diagram showing still another embodiment of the present invention.

FIG. 4 is a view showing an embodiment of a fall prevention device 10;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Tank 2 Control panel 3 Liquid level sensor 4 Float 5 Pulley part 6 Hoisting spring 7 Bearing part 8 Detection sensor 9 Magnet coupling 10 Fall prevention tool 11 Mechanical connection parts

Claims (6)

[Claims] 1. A liquid level sensor in which ventilation between a hoisting pulley portion mechanically connected to a float in a tank and other components is blocked. 2. A liquid level sensor, wherein the hoist pulley is directly connected to a hoist spring and a sensor for detecting a rotational position of the hoist spring. 3. A liquid level sensor, wherein the hoisting pulley, a hoisting spring and a sensor for detecting the rotational position thereof are connected by a magnet. 4. A liquid level sensor according to claim 1, wherein said float and said hoisting pulley are made of resin. 5. The liquid level sensor according to claim 1, wherein said float does not increase its cross-sectional area from an upper portion near a liquid surface in a downward direction. 6. The liquid level sensor according to claim 1, further comprising a stopper for preventing a mechanical connection part between the hoisting pulley and the float from falling off from the hoisting pulley.