JPH0658365U - Liquid flow detector - Google Patents

Abstract

(57) [Summary] [Structure] A transparent large-diameter tubular member 2 is provided in the middle of the cooling pipe 1, and cooling that flows in the tubular member 2 between the middle of the tubular member 2 and the electrode provided on the cooling pipe 1 is performed. An electric circuit A was formed by taking in water 10 as a capacitor, and an appropriate alarm means 16 was connected to the electric circuit A. [Effect] The alarm means 16 can be driven by an electric signal that detects a change in the flow of the cooling water 10 in the tubular member 2 to detect an abnormality in the water flow, and the transparent tubular member 2 can be cooled by seeing through from the outside. The state of water flow can be visually confirmed. Further, since the cylindrical member 2 has a large diameter, the possibility that the scale of the cooling water 10 will adhere to the inner wall is very small, and the flow state of the cooling water can be visually confirmed from the outside for a long period of time, and the maintenance is easy. Become.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a liquid flow detection device that detects when the flow of a liquid has stopped, which is arranged in various types of equipment and devices.

[0002]

[Prior art]

 In order to prevent the motor and IC substrate from overheating in various physics and chemistry / industrial equipment, manufacturing equipment, etc., cooling pipes are installed around them and cooling water is circulated inside. By the way, in the normal case, the cooling water used is pooled secondary water after using purified water, so that water stains tend to accumulate on the inner wall of the cooling pipes, causing cooling due to water stains. It is easy for a part of the reject tube to be clogged. When a clogging phenomenon occurs, the circulation of cooling water is stopped, which may cause a serious accident.Therefore, it is necessary to constantly monitor the cooling water flowing through the cooling pipes in most of the equipment and devices. A liquid flow detector is installed to detect water interruption.

As one detection device, for example, a nozzle is provided in a cooling pipe, cooling water is made to flow in the nozzle, water pressure before and after the nozzle is detected, and it is detected that the pressure difference between the two water pressures becomes abnormally large. There are some that detect when the water flow condition has deteriorated. It is also known to arrange a water turbine inside the cooling pipe and detect that the flow of the cooling water is stopped due to the stop of the water turbine. However, as mentioned above, since the secondary water is used for the cooling water, in the former case, the scale is clogged on the inner wall of the nozzle, and in the latter case, the scale accumulates in the bearing of the turbine and the rotation of the turbine is stopped. Therefore, all of them have the drawback of being prone to malfunction and likely to malfunction.

[0004]

[Problems to be solved by the device]

 SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned drawbacks, and to provide a liquid flow detection device for liquids which has a particularly simple structure, is hard to fail and operates reliably.

[0005]

[Means for Solving the Problems]

 In order to achieve the above-mentioned object, a liquid flow detecting device according to the present invention is provided with a transparent cylindrical member for passing the liquid from one end to the other end in a middle part of a pipe through which the liquid flows. The opening end of the tubular member to the opening is formed to have a diameter smaller than that of the tubular member, and an electrode with which the liquid flowing from the one end to the other end comes into contact is attached to the middle of the tubular member. And an other electrode provided on the tube, an electric circuit incorporating a liquid flowing in the cylindrical member as a dielectric is formed, and an appropriate alarm means is connected to the electric circuit. To do.

[0006]

[Function and effect of the device]

 According to the liquid flow detection device having the above configuration, when the liquid is flowing normally through the tubular member, both electrodes are electrically connected as a capacitor using the liquid as a dielectric.

On the other hand, when the cooling pipe on the water guiding side is clogged, the flow of the liquid is interrupted and the liquid as the dielectric substance does not exist, so that the impedance between both electrodes changes. When the cooling pipe on the drain side is clogged, the flow of the liquid stops and the liquid stays in the tubular member, resulting in a change in the density of the liquid. This also changes the dielectric constant, which changes the impedance between the electrodes. The change in impedance is output as an electric signal and compared with a reference value to drive the alarm means. This makes it possible to know abnormalities in the flow of cooling water in the cooling pipe. Furthermore, the flow state of the cooling water can be visually recognized by seeing through the transparent tubular member from the outside. Moreover, the above-mentioned detection device is very useful because it has a simple structure, is hard to break down, operates reliably, and can be manufactured at low cost.

Further, since the open end of the cooling pipe on the water guiding side is narrowed, the cooling water flowing into the tubular member becomes a rod shape and flows into the cooling pipe on the discharging side. Therefore, the cooling water does not directly contact the inner wall of the tubular member. As described above, since the possibility that the cooling water stains adhere to the inner wall of the cylindrical member is extremely small, the flow state of the cooling water can be visually confirmed from the outside for a long period of time, and the maintenance becomes easy.

[0009]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a cooling water liquid flow detecting device. This liquid flow detecting device is transparent in the middle of a cooling pipe 1 through which a cooling water 10 flows. A cylindrical member 2 is provided, and an electric circuit A is formed between the cylindrical member 2 and the cooling pipe 1 and the cooling water 10 flowing in the cylindrical member 2 is taken in as a capacitor to form a capacitor. The alarm means 16 is connected.

The cooling pipe 1 may be an ordinary metal pipe. A flange 5 is formed so as to project from the open ends of the cooling pipes 1a and 1b on the water introduction side and the discharge side, and the tubular member 2 is arranged between these flanges 5. A sealing material 6 is interposed between the flange 5 and the tubular member 2. The tubular member 2 may be made of a transparent insulating material such as acrylic resin, vinyl chloride resin, or glass. The opening end of the cooling pipe 1 to the opening of the tubular member 2 is formed to have a smaller diameter than that of the tubular member 2. In this case, the opening end 7 of the cooling pipe 1a may be tapered as shown in the figure. Alternatively, the cylindrical member 2 may have a larger diameter than the cooling pipe 1. In short, the diameter difference between the cooling pipe 1 and the tubular member 2 may be such that the cooling water 10 flowing into the tubular member 2 from the water guiding side cooling pipe 1 does not directly contact the inner wall of the tubular member 2. The cooling pipe 1a is provided with a valve 3 so that the flow of the cooling water 10 can be stopped when the detector is maintained.

Next, an electrode 8 with which the cooling water 10 flowing from the one end to the other end contacts is attached to the middle of the tubular member 2, while another electrode 9 is also attached to the cooling pipe 1. Then, a capacitor is formed between the electrodes 8 and 9 by using the cooling water flowing in the tubular member 2 as a dielectric, and an electric circuit A incorporating the capacitor as a part of the circuit is formed. The electric circuit A includes a bridge 11, an AC power supply 12, an amplification circuit 13 for amplifying the detected electric signal, a comparison circuit 14 for comparing the amplified electric signal with a reference voltage, and an appropriate alarm depending on the output of the comparison circuit. And a driver 15 for driving the means 16. The alarm means may be composed of a lamp, a buzzer or the like.

According to the liquid flow detection device having the above structure, when the cooling water 10 normally flows from the cooling pipe 1a on the water guide side to the cooling pipe 1b on the discharge side through the tubular member 2, the cooling water is cooled as a dielectric. Water 10 maintains a predetermined impedance (Z1) between both electrodes 8 and 9. In this state, the impedances (Z2, Z3, Z4) are set so that the bridge 4 is in a balanced state. Each impedance may be adjustable.

When the cooling pipe on the water guide side is clogged, the flow of the cooling water is interrupted, and the cooling water as a dielectric is no longer present, so that the impedance (Z1) between the electrodes 8 and 9 changes. When the cooling pipe on the drainage side is clogged, the flow of the cooling water stops and the cooling water stays in the tubular member, so that the density of the cooling water changes. As a result, the dielectric constant also changes, so that the impedance (Z1) between the electrodes 8 and 9 changes. In either case, the value of the impedance Z1 changes, so that the equilibrium state of the bridge 11 is disturbed and the voltages at points a and b are not equal. As a result, a potential difference is generated between a and b. The voltage change is amplified by the amplifier 13 and input to the input terminal c of the comparator 14. A reference voltage, which is a demarcation point where the water flow is judged to be abnormal, is applied to the input terminal d of the comparator 14 described above, and when the input voltage of the input terminal c exceeds the reference voltage of the input terminal d, the output terminal d The output signal is output to e. The output signal of the comparator is actuated by the driver 15 to activate the alarm means 16. This makes it possible to know an abnormality in the flow of the cooling water 10 in the cooling pipe 1. Further, by displaying the signal amplified by the amplifier 13 on a meter such as a voltmeter, the change in the state can be monitored in analog. Also, because the output voltage differs due to the difference in impedance, it is possible to determine whether the clogging is on the water intake side or the drain side by providing multiple comparators and corresponding alarm indications. Furthermore, the flow state of the cooling water 10 can be visually recognized by seeing through the transparent tubular member 2 from the outside. Moreover, the above-mentioned detection device is very useful because it has a simple structure, is hard to break down, operates reliably, and can be manufactured at low cost. A direct current electric circuit (not shown) using cooling water between both electrodes as a conductor may be configured to output an electric resistance that changes according to the flow rate as an electric signal to drive the alarm means.

Further, since the open end 7 of the cooling pipe 1a on the water guiding side is narrowed, the cooling water 10 flowing into the tubular member 2 becomes a rod shape and flows into the cooling pipe 1b on the discharging side. Therefore, the cooling water 10 does not directly contact the inner wall of the tubular member 2. As described above, the possibility that the scale of the cooling water 10 adheres to the inner wall of the tubular member 2 is very small, so that the flow state of the cooling water 10 can be visually confirmed from the outside for a long period of time, and the tubular member 2 Since the sealing process between the electrode and the electrode 8 is simple, maintenance becomes easy.

Although the above example describes the detection of the cooling water flow, by setting each impedance (Z2, Z3, Z4) of the bridge 11 and the reference voltage of the comparator 14, a petroleum product, It can be used as a liquid flow detection device for other liquids such as chemicals.

Further, the above example is an example of one cooling pipe 1, but when there are a plurality of cooling pipes 1, one cooling pipe 1 formed in a spiral shape or a meandering shape is arranged at the same position. When the flow state of the cooling water 10 is to be detected by the method described above, a liquid flow detection device may be attached to each cooling pipe 1 as shown in FIG.

[Brief description of drawings]

FIG. 1 is an explanatory cross-sectional view of a cooling water liquid flow detection device according to the present invention.

FIG. 2 is an explanatory view of another example of the cooling water liquid flow detection device.

[Explanation of symbols]

 1 Cooling Pipe 2 Cylinder Member A Electric Circuit 10 Cooling Water 16 Alarm Means

Claims (1)

[Scope of utility model registration request] 1. A midway portion of a pipe through which a liquid flows,
A transparent tubular member that allows the liquid to pass from one end to the other end is provided, and an opening end of the pipe to the opening of the tubular member is formed to have a diameter smaller than that of the tubular member. An electrode with which the liquid flowing toward the other end comes into contact is attached, and an electric circuit is formed between the electrode and another electrode provided on the tube as a capacitor having the liquid flowing in the tubular member as a dielectric. A liquid flow detecting device for a liquid, wherein an appropriate alarm means is connected to the electric circuit.