JP3073164U - Liquid level control device - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide a liquid level control device that accurately controls a liquid level altitude by using a conductivity coefficient. SOLUTION: A plurality of conductive coefficient terminals (1) having different lengths are provided.
0, 12, 14) are provided in the water storage tank (30), and each conductivity coefficient terminal (10, 12, 14) is connected to the control circuit (20).

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 The present invention relates to a liquid level control device for controlling a liquid level altitude by using a conductivity coefficient.

[0002]

[Prior art and its problems]

 At present, water is one of the essential elements in industrial manufacturing processes. Therefore, most manufacturing facilities are equipped with water storage tanks for supplying water or storing a large amount of water, thereby smoothly supplying water required for manufacturing. In addition, in order to prevent the water shortage in the water storage tank during the manufacturing process, a liquid level control device capable of controlling the level of the liquid level is provided in most of the water storage tanks.

Further, the conventional liquid level control device in the water storage tank controls the rise and fall of the liquid level by a ball valve to perform injection into the water storage tank and stop the injection. Can be reliably achieved. However, the conventional liquid level control device using a ball valve can only control at two points, the injection point and the injection stop point, and cannot control the altitude of the liquid level more finely. The application range is very narrow, and the volume of a general industrial water storage tank is extremely large, so that a liquid level control device using such a ball valve cannot exhibit excellent effects.

[0004] In view of the above, a liquid level control device combining a ball valve and a cord has been provided, and this device mainly includes a cord that moves when the ball valve moves up and down the liquid surface. By doing so, control of the liquid level altitude is achieved. However, such a liquid level control device can be applied to a relatively deep water storage tank, in which case the string becomes loose during raising and lowering of the ball valve, reducing the accuracy of the liquid level altitude control. Would. Therefore, there is room for further improvement of this control device.

Further, apart from the above-described liquid level control device, a combination of a ball valve and a magnetic switch is also provided. The liquid level control device includes a plurality of magnetic valves at a predetermined height in a water storage tank. A switch is installed, and when the ball valve goes up and down due to a change in liquid level altitude, the magnetic switch senses this and controls the liquid level. However, this type of liquid level control device is very expensive to manufacture and requires the ball valve to be moved on a specific hoisting line, so if the ball valve moves in another direction. In this case, the sensing by the magnetic switch may be affected, and in the worst case, a problem such as inability to control the liquid level may occur.

[0006] In order to solve the above-mentioned problems, an optical sensor type liquid level control device is subsequently provided, the main feature of which is that a light source is installed on the upper surface of the water storage tank and a sensor is installed on the lower surface. The sensor measures the brightness and determines and controls the liquid level altitude. However, the liquid level control device of the optical sensor type also has a very high manufacturing cost, is easily affected by external light, and in some cases, the control device may make a wrong judgment and malfunction. Accordingly, a further improved electrode type liquid level control device has been provided thereafter. Its main feature is to determine whether each electrode is energized and to control the liquid level. The energization between each electrode depends on whether the ions in the water can be used as a conductive medium. However, most of the water in industrial water storage tanks at present is pure water, and the amount of ions in the pure water is very small, so that it is difficult to produce a conductive effect. Therefore, the electrode type liquid level control device cannot be applied in a pure water environment, and the range of use is considerably limited.

[0007] The present invention solves the above-mentioned problems, and provides a plurality of conductive coefficient terminals of different lengths in a water storage tank and connects each conductive coefficient terminal to a control circuit, thereby providing each conductive coefficient terminal with a control circuit. Since the conductivity coefficient is measured between the coefficient terminals and the liquid level is controlled by the conductivity coefficient, it can be used even in pure water having a constant conductivity coefficient value. Therefore, the applicable range of the liquid level control device can be further expanded.

[0008]

[Means for Solving the Problems]

 According to the present invention, a plurality of conductivity coefficient terminals (10, 12, 14) having different lengths are provided in a water storage tank (30), and each conductivity coefficient terminal (10, 12, 14) is provided with a control circuit (20). And a liquid level control device, characterized in that the liquid level control device is connected to the liquid level control device.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a schematic diagram of the liquid level control device according to the present invention, FIG. 2 is a schematic diagram when the liquid level control device according to the present invention is operated, and FIG. 3 is a liquid level control device according to the present invention. FIG. 4 is a schematic diagram when water is injected into a water storage tank in the control device, and FIG. 4 is a comparison table of a conductivity coefficient and a resistance value of the liquid level control device according to the present invention.

As shown in FIG. 1, in the liquid level control device of the present invention, a plurality of conductive coefficient terminals (10, 12, 14) having different lengths are provided in a water storage tank (30). The coefficient terminals (10, 12, 14) are connected to the control circuit (20), and the respective conductivity coefficient terminals (10, 12, 14) are combined with each other, whereby the water content in the water storage tank (30) is reduced. The conductivity coefficient is measured.

The conductivity coefficient is equal to the reciprocal of a resistance value and can be represented by k = 1 / R.

[0013] k is a conductivity coefficient, and R is a resistance value. Therefore, for example, when the resistance value of water is 2 MΩ-cm, the conductivity coefficient is 0.5 μS / cm.

Further, as shown in FIG. 4, different control circuits (20) are used depending on the installation position, quantity, or use state of the liquid level control of the conductivity coefficient terminals (10, 12, 14). Therefore, the description is omitted.

According to the current pure water production technology, the limit value of the resistance value of pure water is about 18.2 MΩ-cm, and the conductivity at that time is 0.0548 μS / cm. Therefore, even if the concentration of ions in pure water becomes lower than a certain level, the conductivity coefficient in water can be measured by the three conductivity coefficient terminals (10, 12, 14) as shown in FIG. The three conductivity coefficient terminals (10, 12, 14) are located at different heights in the water storage tank (30), respectively. When the water in the water storage tank (30) is used and is gradually lowered, the conductivity coefficient terminal (14) provided at the highest position moves away from the water surface as shown in FIG. At this time, the conductivity coefficient value measured by the conductivity coefficient terminal (14) and the conductivity coefficient terminal (10, 12) in water becomes almost zero due to the interference of air, but the conductivity coefficient terminal (10, 12) in water. )), A constant conductivity value is measured because there is no air interference.

When the liquid level further falls and the conductivity coefficient terminal (12) moves away from the water surface, as shown in FIG. 3, the conductivity coefficient is changed by the conductivity coefficient terminal (12) and the conductivity coefficient terminal (10) in water. The conductivity coefficient value is almost zero due to air interference. Thereby, the control circuit (20) sends an operation signal to the motor (unsigned), injects water into the water storage tank (30) from the inlet, and the liquid level reaches the height shown in FIG. Upon reaching, the constant conductivity coefficient value is measured again by the conductivity coefficient terminal (10) provided at the lowest position and the conductivity coefficient terminal (12) provided at the next lowest position. Further, when the liquid level reaches the height shown in FIG. 1, that is, when the conductivity coefficient terminal (14) is located in the water, the conductivity coefficient terminal (14) and another conductivity coefficient terminal (10) , 12), a constant conductivity value is measured. At this time, the control circuit (20) sends an operation stop signal to the motor. Therefore, the liquid level control device of the present invention controls the height of the liquid level in the water storage tank (30) by the three conductivity coefficient terminals (10, 12, 14), so that the water level of the water storage tank (30) is always maintained. Since the amount of water can be kept constant, the effect of liquid level control can be achieved and the problem of water shortage can be solved.

[0017]

[Effect of the invention]

 Since the present invention has the above-described structure, the conductivity coefficient is measured by each conductivity coefficient terminal (10, 12, 14), thereby achieving the function of controlling the liquid level in the water storage tank (30). A plurality of conductivity coefficient terminals (10, 12, 14) and a control circuit (20) combined with the conductivity coefficient terminals (10, 12, 14) make it possible to achieve an accurate and excellent liquid level control effect. Therefore, the cost of the user can be reduced, and pure water having a low ion concentration, that is, pure water having a low conductivity can be used.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a liquid level control device according to the present invention.

FIG. 2 is a schematic diagram of the operation of the liquid level control device according to the present invention.

FIG. 3 is a schematic diagram when the water is injected into the water storage tank in the liquid level control device according to the present invention.

FIG. 4 is a comparison table of the conductivity coefficient and the resistance value of the liquid level control device according to the present invention.

[Explanation of symbols]

 10, 12, 14 Conductivity coefficient terminal 20 Control circuit 30 Water storage tank

Claims (1)

[Utility model registration claims] A plurality of conductive coefficient terminals having different lengths (1).
0, 12, 14) are provided in the water storage tank (30), and each conductivity coefficient terminal (10, 12, 14) is connected to the control circuit (2, 12).
A liquid level control device, which is connected to 0).