JPH0592652U - Liquid flow meter - Google Patents

Abstract

(57) [Summary] [Purpose] To obtain a small-sized liquid flowmeter that is not affected by noise and the like. [Structure] A water tank 7 having a weir 11 is connected to a pedestal 10 through an elastic optical fiber 8. The elastic optical fiber 8 is compressed and deformed according to the amount of liquid flowing in from the inlet 3, that is, the weight of the liquid accumulated in the water tank 7, and the amount of transmitted light changes. The change in the transmitted light amount is converted into a current or a voltage and detected to detect the position of the water tank 7. The liquid flow rate is calculated and displayed on the calculation display 16 based on the position of the water tank 7.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a liquid flow meter for measuring the flow rate of liquids such as water, oil and chemicals, and more particularly to a liquid flow meter for measuring the flow rate of liquid passing through a weir by detecting the position of a water tank equipped with the weir.

[0002]

[Prior Art]

 An example of this type of weir flowmeter is disclosed in Japanese Utility Model Laid-Open No. 60-54920. In this method, a water tank equipped with a weir is suspended in a measurement chamber by a spring, and the position of the water tank is detected by a differential transformer to measure the amount of liquid passing through the weir.

[0003]

[Problems to be solved by the present invention]

 In the above conventional liquid flowmeter, since the position of the water tank is detected by the operating transformer, there is a problem that the position of the water tank cannot be accurately detected due to electromagnetic noise. In addition to this, even if the position of the water tank is detected with a potentiometer, the position of the water tank cannot be accurately detected due to the sliding resistance of the potentiometer, and the position of the water tank is detected via a lever or diaphragm. However, there is a problem in that the structure is complicated and the shape becomes large and expensive because it requires connection with a lever or a diaphragm. Therefore, the technical problem of the present invention is to make it possible to accurately detect the position of the water tank in a small size without being affected by noise or the like.

[0004]

[Means for Solving the Problems]

 The technical means of the present invention, which has been taken to solve the above technical problems, is a liquid flow meter that arranges a water tank equipped with a weir in a measurement chamber and detects the position of the water tank to measure the amount of liquid passing through the weir. In the above, the water tank is connected to the pedestal via an elastic optical fiber, and the position of the water tank is detected as a change in the amount of transmitted light passing through the elastic optical fiber.

[0005]

[Action]

 The operation of the above technical means is as follows. The elastic optical fiber is rich in flexibility and can be easily compressed or stretched by forming the core or clad with an elastic material such as synthetic rubber or plastic. There is a correlation between the flow rate of the liquid passing through the weir and the water level in the water tank, that is, the weight of the liquid in the water tank. In addition, the position of the water tank equipped with a weir is changed by compressing or pulling the elastic optical fiber in accordance with the weight of the liquid stored inside it. Therefore, by detecting the change in the transmitted light amount due to the compression or tensile deformation of the elastic optical fiber, the position of the water tank due to the weight of the liquid in the water tank can be detected, and the liquid body flow rate passing through the weir can be detected.

[0006]

【Example】

 An embodiment showing a specific example of the above technical means will be described (see FIG. 1). In the case 1, the measurement chamber 2, the inlet 3 for introducing the liquid to be measured into the measurement chamber 2, the drainage chamber 5 into which the liquid in the measurement chamber 2 flows through the communication port 4, and the liquid in the drainage chamber 5 to the outside To form an outlet 6 that discharges into A water tank 7 having an upper opening is arranged inside the measurement chamber 2. The inlet 3 extends inwardly above the opening of the aquarium 7 so that liquid enters the aquarium 7. The water tank 7 is placed on the pedestal 10 via the elastic optical fiber 8 and the elastic body 9, and the weir 11 is opened on the side wall. The pedestal 10 is formed on a partition wall 12 formed integrally with the casing 1. The elastic optical fiber 8 has a core portion (not shown) and a clad portion (not shown) made of an elastic material such as silicon rubber, and a light source portion 13 and a light detection portion 14 are provided at both ends thereof. The light source section 13 is formed of a light emitting element such as a light emitting diode, and the light detection section 14 is formed of a light receiving element such as a photo diode. The liquid is prevented from accumulating on the bottom of the measuring chamber 2 and the buoyancy does not act on the water tank 7. Therefore, the communication port 4 is provided so that the liquid accumulated at the bottom of the measurement chamber 2 can be immediately removed. The liquid flowing from the communication port 4 into the drainage chamber 7 is discharged to the outlet 6 by the drainage valve including the float 15. Reference numeral 16 is a calculation display for calculating and displaying the flow rate.

The liquid from the inlet 3 enters the inside of the water tank 7 through the upper opening and flows out from the weir 11. When the amount of liquid flowing in from the inlet 3 is large, the liquid level inside the water tank 7 is high, and the water tank 7 is largely displaced downward against the elastic optical fiber 8 and the elastic body 9. Since the -8 is largely deformed into a concave shape, the amount of transmitted light of the elastic optical fiber-8 is greatly reduced. When the amount of liquid flowing in from the inlet 3 is small, the liquid level inside the water tank 7 is low, the compressive deformation of the elastic optical fiber 8 is small, and the decrease in the amount of transmitted light is small. In this way, the amount of light transmitted through the elastic optical fiber 8 changes according to the amount of liquid flowing in from the inlet 3, that is, according to the weight of the liquid accumulated inside the water tank 7. By converting this change in the transmitted light amount into a current or a voltage and detecting it, it can be detected as the position of the water tank 7. The liquid flow rate is calculated and displayed on the calculation display 16 based on the position of the water tank 7.

In the above-described embodiment, an example in which the compressive deformation of the elastic optical fiber increases when the liquid level in the water tank rises has been shown. However, the compressive deformation of the elastic optical fiber decreases. Good. Further, although the elastic optical fiber is arranged below the container, it is not limited to this.

[0009]

[Effect of the device]

 The present invention has the following unique effects. As described above, according to the present invention, it is possible to miniaturize the flowmeter itself with a simple structure without using a lever or a diaphragm, and to detect the change of the optical signal so that the flowmeter is not affected by noise or the like. It is difficult to measure the flow rate more accurately. Further, the detection signal can be transmitted to a long distance without being affected by noise and the like due to the optical signal, and it is possible to easily perform centralized control of a large number of flow rate measurements at one place.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a liquid flow meter according to an embodiment of the present invention.

[Explanation of symbols]

 2 Measuring chamber 3 Inlet 6 Outlet 7 Water tank 8 Elastic optical fiber-10 Pedestal 11 Weir 16 Calculation display

Claims (1)

[Scope of utility model registration request] 1. A method for arranging a water tank equipped with a weir in a measurement chamber and detecting the position of the water tank to measure the amount of liquid passing through the weir,
A flowmeter for liquids in which a water tank is connected to a pedestal via an elastic optical fiber, and the position of the water tank is detected as a change in the amount of light transmitted through the elastic optical fiber.