JP4493010B2 - Flow rate / residual chlorine concentration measuring instrument and tap water flow rate / residual chlorine concentration measurement method - Google Patents

Description

  The present invention relates to a flow rate / residual chlorine concentration measuring instrument comprising an electromagnetic flow sensor for detecting the flow rate of tap water and a residual chlorine sensor for detecting residual chlorine concentration of tap water, and the electromagnetic flow sensor and residual chlorine. The present invention relates to a method for measuring the flow rate and residual chlorine concentration of tap water using a sensor.

  In order to manage tap water, an electromagnetic flow sensor is attached to a predetermined location of the water pipe network, and a residual chlorine concentration detector for performing a residual chlorine concentration reagent test at another location of the water pipe network. Is provided. In recent years, a residual chlorine sensor using an oxidation-reduction reaction has been used in place of a reagent test, and the above-mentioned residual chlorine concentration detection unit has been abolished and remains in the vicinity of a conventionally used electromagnetic flow sensor. A chlorine sensor was attached, whereby an electromagnetic flow sensor and a residual chlorine sensor were arranged side by side in the axial direction of the water pipe to measure the flow rate and residual chlorine concentration of tap water.

  By the way, the direction of the tap water flowing through the water pipe network changes according to the usage status of the tap water of a plurality of households connected to the water pipe network. Therefore, in the conventional method for measuring the flow rate and residual chlorine concentration of tap water described above, the electrode of the electromagnetic flow sensor may be located downstream of the electrode of the residual chlorine sensor, and the influence of ions generated when the residual chlorine sensor is used As a result, the accuracy of flow measurement by the electromagnetic flow sensor may become unstable.

  In addition, the patent document which disclosed the prior art which concerns on this invention was not able to be found.

  The present invention has been made in view of the above circumstances, and is capable of measuring the flow rate and residual chlorine concentration of tap water at one place in the water pipe network, and is stable even if the direction in which the tap water flows changes. The purpose is to provide a flow rate / residual chlorine concentration measuring device capable of measuring the flow rate and a method for measuring the flow rate / residual chlorine concentration of tap water.

The flow rate / residual chlorine concentration measuring device according to the invention of claim 1 made to achieve the above object includes a body having a flow path through which tap water is flowed, and a pair of flow rates disposed opposite to each other in the flow path. A pair of flow measurement electrodes in a state in which magnetic flux is applied to the flow path from a pair of electromagnetic coils opposed to each other in a direction substantially perpendicular to the facing direction of the pair of flow measurement electrodes. The sensor has an electromagnetic flow sensor for detecting the flow rate of tap water based on the potential difference generated between the electrodes and a pair of residual chlorine concentration measurement electrodes arranged in the flow path. A predetermined voltage is applied from the DC power source between the measurement electrodes, and the residual for detecting the residual chlorine concentration of tap water based on the current flowing between the pair of residual chlorine concentration measurement electrodes via the tap water Flow rate and residual chlorine concentration measuring instrument equipped with a chlorine sensor The residual chlorine sensor is provided in pairs at two locations sandwiching the electromagnetic flow sensor in the axial direction of the flow path, and a determination means for determining the direction in which the tap water flows based on the detection result of the electromagnetic flow sensor, The present invention is characterized in that, based on the determination result of the means, a residual chlorine sensor switching means for switching to stop the residual chlorine sensor on the upstream side while using the residual chlorine sensor on the downstream side is provided.

  According to a second aspect of the present invention, in the flow rate / residual chlorine concentration measuring device according to the first aspect, each residual chlorine sensor is arranged with a phase difference of about 90 degrees around the axis in the flow path with respect to the flow rate measuring electrode. It has the characteristics where it was done.

According to a third aspect of the present invention, in the flow rate / residual chlorine concentration measuring device according to the second aspect, each residual chlorine sensor is provided with a sensor housing in which a pair of residual chlorine concentration measuring electrodes are integrally fixed . A characteristic is that the sensor housings of both residual chlorine sensors are fixed to the flow path at positions where the phases are shifted by about 180 degrees around the axis.

According to a fourth aspect of the present invention, in the flow rate / residual chlorine concentration measuring device according to any one of the first to third aspects, the discriminating means has a direction in which the tap water flows and an absolute value of the flow rate of the tap water is a predetermined standard. The residual chlorine sensor switching means receives the determination result of the determination means, and if the absolute value of the flow rate of tap water is smaller than a predetermined reference value, the residual chlorine sensor switching means When the sensor is stopped and the absolute value of the flow rate of tap water is larger than the reference value, the sensor is switched to use only the residual chlorine sensor on the downstream side.
Here, the “absolute value of the flow rate of tap water” may be an absolute value of a substitute value of the flow rate of tap water. Therefore, the “absolute value of the flow rate of tap water” includes the absolute value of the potential difference between the pair of flow measurement electrodes.

The method for measuring the flow rate and residual chlorine concentration of tap water according to the invention of claim 5 provides an electromagnetic flow sensor having a pair of flow measurement electrodes facing each other in a direction crossing the magnetic flux. It measures the flow rate of tap water flowing through the water pipe and uses two residual chlorine sensors with a pair of residual chlorine concentration measurement electrodes, which are arranged upstream and downstream from the electromagnetic flow sensor. In a method for measuring the flow rate and residual chlorine concentration of tap water, which uses two residual chlorine sensors to measure the residual chlorine concentration of tap water by performing an oxidation-reduction reaction between a pair of residual chlorine concentration measurement electrodes and tap water Based on the detection result of the electromagnetic flow sensor, the direction of the tap water flow is determined, and the residual chlorine sensor downstream from the electromagnetic flow sensor is used according to the direction of the tap water flow at that time, while the upstream side Residual chlorine sensor It has a feature where the switch to stop.

[Invention of Claim 1]
Since the flow rate / residual chlorine concentration measuring device of claim 1 includes an electromagnetic flow sensor and a residual chlorine sensor, tap water can be used at one place in the water pipe network by using the flow rate / residual chlorine concentration measuring device. The flow rate and residual chlorine concentration can be measured. Then, when the direction in which the tap water flows is changed, the residual chlorine sensor to be used is switched among the pair of residual chlorine sensors arranged at two positions across the electromagnetic flow sensor, and the residual flow downstream of the electromagnetic flow sensor is always changed. Only the chlorine sensor is used, and the upstream residual chlorine sensor is stopped. As a result, ions generated when the residual chlorine sensor is used do not affect the measurement accuracy of the electromagnetic flow sensor, and the flow rate can be stably measured even if the direction in which the tap water flows changes.

[Invention of claim 2]
In the flow rate / residual chlorine concentration measuring device according to claim 2, each residual chlorine sensor is arranged at a position where the phase is shifted by about 90 degrees around the axial center in the flow path with respect to the pair of flow measurement electrodes. As a result, immediately after switching the residual chlorine sensor to be used from one to the other, even if ions generated in one residual chlorine sensor flow to the electromagnetic flow sensor side, the ions are Passing through a position that is approximately 90 degrees out of phase around the axis of the flow path, the influence on the measurement accuracy of the electromagnetic flow sensor can be suppressed.

[Invention of claim 3]
In the flow rate / residual chlorine concentration measuring device of claim 3, each residual chlorine sensor has a structure in which a pair of residual chlorine concentration measuring electrodes are integrally fixed to the sensor housing. Thereby, handling of the residual chlorine sensor is facilitated, and a pair of residual chlorine concentration measurement electrodes of each residual chlorine sensor can be collectively attached to one place of the flow path. Since both the sensor housings of the pair of residual chlorine sensors are arranged in the flow path at positions that are substantially 180 degrees out of phase with each other around the axis, immediately after switching the residual chlorine sensor to be used from one to the other In addition, even if ions generated in one residual chlorine sensor flow to the other residual chlorine sensor, the ions are approximately 180 degrees out of phase with respect to the residual chlorine sensor around the axis of the flow path. Passing through the position, the influence on the measurement accuracy of the other residual chlorine sensor can be suppressed.

[Invention of claim 4]
According to the flow rate / residual chlorine concentration measuring device of claim 4, when the tap water is flowing toward the one side at a flow rate larger than the reference value, only one residual chlorine sensor located downstream of the electromagnetic flow rate sensor at this time is used. When the tap water is flowing at a flow rate larger than the reference value toward the other side, only the other residual chlorine sensor located at the downstream side of the electromagnetic flow rate sensor at this time is used. When the absolute value of the flow rate becomes smaller than the reference value and the direction of the tap water flow is unstable, both residual chlorine sensors are stopped. This makes it possible to reliably use only the residual chlorine sensor downstream of the electromagnetic flow sensor.

[Invention of claim 5]
According to the method for measuring the flow rate and residual chlorine concentration of tap water according to claim 5, the residual chlorine sensor on the upstream side is used while the residual chlorine sensor on the downstream side of the electromagnetic flow sensor is used according to the direction of the flow of tap water. Since the operation is stopped, ions generated when the residual chlorine sensor is used do not affect the measurement accuracy of the electromagnetic flow sensor, and the flow rate can be stably measured even if the direction in which tap water flows is changed. Thereby, the electromagnetic flow sensor and the residual chlorine sensor can be disposed adjacent to each other, and the flow rate of the tap water and the residual chlorine concentration can be measured at one place in the water pipe network. In addition, since the detection result of the electromagnetic flow sensor is used to determine the direction of the tap water flow, the cost can be reduced compared to the case where a separate means for determining the direction of the tap water flow is provided. Can be planned.

Hereinafter, an embodiment of the present invention will be described with reference to FIGS.
A flow rate / residual chlorine concentration measuring instrument 10 (hereinafter simply referred to as “measuring instrument 10”) according to the present embodiment shown in FIG. 1 includes a pipe member 11 as a body according to the present invention. A flow sensor 20 (hereinafter simply referred to as “flow sensor 20”) and a pair of residual chlorine sensors 30 and 30 are attached.

  Both ends of the pipe member 11 are provided with flanges 11F and 11F, and the flanges 12F of the water pipe 12 are joined to the flanges 11F and 11F and fixed with bolts. As a result, the water pipe 12 and the pipe member 11 are in communication with each other, and the tap water flows through the flow path 13 in the pipe member 11. Here, the water pipe 12 to which the measuring instrument 10 is attached constitutes a part of a water pipe network (not shown), and the water flowing through the water pipe 12 in accordance with the usage status of the dwelling group connected to the water pipe network. The direction of water changes.

  The flow sensor 20 is attached to an intermediate portion in the axial direction of the pipe member 11. In addition, the flow sensor 20 includes a pair of electromagnetic coils 21 and 21 and a pair of flow measurement electrodes 22 and 22 (see FIG. 2. Only one flow measurement electrode 22 is shown in FIG. 1. ). The pair of electromagnetic coils 21 and 21 are opposed to each other with the intermediate portion in the longitudinal direction of the pipe member 11 sandwiched in the radial direction. These electromagnetic coils 21 and 21 are excited by an excitation circuit (not shown) to generate a magnetic flux in the same direction. That is, when the electromagnetic coils 21 and 21 are excited, the magnetic flux passes through the one electromagnetic coil 21, the pipe member 11, and the other electromagnetic coil 21 in this order, and the tap water flows through the flow path 13 so as to intersect the magnetic flux. .

A portion of the pipe member 11 facing in the direction substantially orthogonal to the facing direction of the electromagnetic coils 21 and 21 is configured by an insulating member 23. The pair of flow measurement electrodes 22 and 22 are arranged so as to face each other in a direction substantially orthogonal to the facing direction of the electromagnetic coils 21 and 21 (that is, the direction of magnetic flux) and attached to the insulating member 23. Yes. Specifically, the center lines of the electromagnetic coils 21 and 21 are orthogonal to the center line of the flow path 13, and the lines orthogonal to both the center lines of the electromagnetic coils 21 and 21 and the center line of the flow path 13 are insulated. A sensor mounting hole 23 </ b> A is formed in a portion that penetrates the member 23. The flow rate measurement electrode 22 is held in each sensor mounting hole 23 </ b> A, and the tip of the flow rate measurement electrode 22 is immersed in tap water flowing in the flow path 13.

  With the configuration described above, when tap water flows through the flow path 13 and crosses the magnetic flux, a potential difference corresponding to the flow rate is generated between the flow measurement electrodes 22 and 22. As shown in FIG. 2, the potential difference between the flow rate measuring electrodes 22 and 22 is amplified by an OP amplifier 53 and taken into the flow rate sensor CPU 52 of the control circuit 50. The flow rate sensor CPU 52 calculates and outputs the flow rate of tap water from the captured potential difference. Here, in the present embodiment, for example, the potential difference and the flow rate between the flow rate measuring electrodes 22 and 22 when the tap water flows in the right direction in FIG. It is assumed that the potential difference and the flow rate between the flow rate measuring electrodes 22 and 22 when flowing are “negative”.

  As shown in FIG. 1, the residual chlorine sensors 30, 30 are arranged at positions sandwiching the flow sensor 20 in the axial direction of the pipe member 11. Further, as shown in FIG. 3, each residual chlorine sensor 30 includes a sensing electrode 33 and a base electrode 32 corresponding to a pair of residual chlorine concentration measurement electrodes according to the present invention fixed to the sensor housing 31. It has a structure. The sensor housing 31 is made of, for example, an insulating member, and has a structure in which a flange portion 35 projects laterally from the rear end portion of the screw portion 34. The sensing electrode 33 is, for example, a platinum negative electrode, has a cylindrical shape, and protrudes from the tip of the screw portion 34. The base electrode 32 is, for example, a silver positive electrode, is disposed inside the sensing electrode 33, and slightly protrudes from the tip of the sensing electrode 33. The base electrode 32 and the sensing electrode 33 are insulated by an insulating member 31A. Further, lead wires 36 </ b> A and 36 </ b> B connected to the electrodes 32 and 33 extend from the rear end surface of the sensor housing 31.

  As shown in FIG. 1, the pipe member 11 is formed with screw holes 37, 37 through which the residual chlorine sensors 30, 30 are screwed and assembled at positions closer to both ends thereof. One screw hole 37 is disposed between one electromagnetic coil 21 and the flange 11F on one end side of the pipe member 11, and the other screw hole 37 is on the other electromagnetic coil 21 and the other end side of the pipe member 11. It is arrange | positioned between the flanges 11F. The screw portions 34 of the residual chlorine sensors 30, 30 are screwed into the screw holes 37, 37. As a result, the residual chlorine sensors 30 and 30 are disposed in the flow path 13 with a phase difference of about 180 degrees around the axis, and at about 90 with respect to both the flow rate measuring electrodes 22 and 22 of the flow rate sensor 20. The phase is shifted by a degree.

  When each residual chlorine sensor 30 is screwed into the screw hole 37, the sensing electrode 33 and the base electrode 32 are immersed in tap water in the flow path 13. When a voltage is applied between the sensing electrode 33 and the base electrode 32 of the residual chlorine sensor 30 in this state, an oxidation-reduction reaction is performed between the sensing electrode 33 and the base electrode 32 and tap water. A current flows between the electrodes 32 and 33 through the tap water. The residual chlorine concentration is detected by utilizing the fact that the current value increases as the residual chlorine concentration of tap water increases.

  As shown in FIG. 2, the control circuit 50 is provided with a switch 56 for selectively using both residual chlorine sensors 30, 30. The positive terminal of the DC power source 57 is always connected to the input terminal of the switch 56. Further, a first output terminal 56A and a second output terminal 56B are provided on the output side of the switch 56, and the first output terminal 56A has a residual chlorine sensor 30 on the right side in FIG. 1 is connected to the lead wire 36A of the sensing electrode 33, and the second output terminal 56B is connected to the left residual chlorine sensor 30 in FIG. 1 (hereinafter referred to as “second residual chlorine sensor 30” as appropriate). The lead wire 36A of the sensing electrode 33 is connected. In accordance with an external drive signal, the DC power source 57 and the first residual chlorine sensor 30 are connected, the DC power source 57 and the second residual chlorine sensor 30 are connected, It can be switched to the state separated from the chlorine sensors 30 and 30.

  The lead wire 36 B of the base electrode 32 in the first residual chlorine sensor 30 and the lead wire 36 B of the base electrode 32 in the second residual chlorine sensor 30 are parallel to one input terminal of the OP amplifier 55 provided in the current / voltage conversion circuit 58. It is connected. The negative electrode of the DC power source 57 and the other input terminal of the OP amplifier 55 are GND-connected. As a result, the current value flowing between the sensing electrode 33 and the base electrode 32 of the residual chlorine sensor 30 connected to the DC power source 57 by the switch 56 is taken into the control circuit 50 as a voltage signal. The residual chlorine sensor CPU 54 provided in the control circuit 50 calculates and outputs the residual chlorine concentration based on the current value flowing between the sensing electrode 33 and the base electrode 32.

  The residual chlorine sensor CPU 54 uses the residual chlorine sensor 30 on the downstream side of the flow sensor 20 according to the direction of the tap water in the flow path 13, while the residual chlorine sensor 30 on the upstream side of the flow sensor 20. The switch 56 is controlled to stop. For this purpose, the residual chlorine sensor CPU 54 executes the switch control program P1 shown in FIG. 4 at a predetermined cycle (for example, 10 [ms]).

  When the switch control program P1 is executed, a potential difference ΔV (corresponding to the “detection result of the electromagnetic flowmeter” according to the present invention) between the flow measurement electrodes 22 and 22 is captured as a detection signal of the flow sensor 20 ( S1). Then, it is determined whether or not the potential difference ΔV is “positive” (S2). If the potential difference ΔV is “positive” (YES in S2), tap water is flowing rightward in FIG. The switch 56 connects the DC power source 57 to the first output terminal 56A side (S3). Thereby, when the tap water flows in the right direction in FIG. 1, only the first residual chlorine sensor 30 located on the downstream side (residual chlorine sensor 30 on the right side in FIG. 1) is connected to the DC power source 57 and is located on the upstream side. The second residual chlorine sensor 30 (the residual chlorine sensor 30 on the left side in FIG. 1) is disconnected from the DC power source 57.

  On the other hand, if the potential difference ΔV is not “positive” (NO in S2), it is determined that tap water is flowing leftward in FIG. 1, and the DC power source 57 is connected to the second output terminal 56B side by the switch 56. (S4). Thereby, when the tap water flows in the left direction in FIG. 1, only the second residual chlorine sensor 30 (the residual chlorine sensor 30 on the left side in FIG. 1) located on the downstream side is connected to the DC power source 57 and located on the upstream side. The first residual chlorine sensor 30 (the residual chlorine sensor 30 on the right side in FIG. 1) is disconnected from the DC power source 57.

In this way, every time the switch control program P1 is executed at a predetermined cycle, the direction in which tap water flows is determined based on the potential difference between the flow rate measuring electrodes 22 and 22, and the flow sensor 20 is always in the flow. Only the residual chlorine sensor 30 on the downstream side is used, and the residual chlorine sensor 30 on the upstream side is stopped.
In the present embodiment, the above-described step S2 constitutes the “discriminating means” according to the present invention. The switch 56 and steps S3 and S4 described above constitute the “residual chlorine sensor switching means” according to the present invention.

Next, the operation of the present embodiment configured as described above will be described.
The measuring instrument 10 of this embodiment is attached to a plurality of locations in the water pipe network, and the detection results of these measuring instruments 10 are collected in a management office by, for example, communication means (not shown), and the flow rate and residual chlorine concentration of tap water are Managed. Specifically, when the measuring instrument 10 is activated by a remote operation from the management office, the flow rate of the tap water is measured by the flow sensor 20 provided in the measuring instrument 10 and the residual chlorine sensor 30 provided in the measuring instrument 10. Detects the residual chlorine concentration of tap water. At this time, the switch control program P1 is repeatedly executed at a predetermined cycle (for example, 10 [ms]) with the activation of the measuring instrument 10. Then, each time the switch control program P1 is executed, the direction in which the tap water flows is determined based on the potential difference ΔV between the flow measurement electrodes 22 and 22. Based on the determination result, only the residual chlorine sensor 30 on the downstream side of the flow sensor 20 is always used, and the residual chlorine sensor 30 on the upstream side is stopped. This prevents ions generated when the residual chlorine concentration is measured by the residual chlorine sensor 30 from flowing to the flow rate measurement electrode 22 side of the flow rate sensor 20.

  When the measurement is completed, the measuring instrument 10 is stopped by remote control from the management office. Then, any residual chlorine sensors 30, 30 are disconnected from the DC power source 57 by the switch 56. Further, excitation by the electromagnetic coil 21 of the flow sensor 20 is not performed. This prevents unnecessary power consumption and the generation of ions.

  Thus, according to the measuring instrument 10 of this embodiment, since the flow sensor 20 and the residual chlorine sensor 30 are provided, it is possible to measure the flow rate and residual chlorine concentration of tap water at one place in the water pipe network. become. And even if the direction of the tap water flowing in the water pipe network changes, only the residual chlorine sensor 30 on the downstream side of the flow sensor 20 is always used and the residual chlorine sensor 30 on the upstream side is stopped. The ions generated during use of 30 do not affect the measurement accuracy of the flow rate sensor 20, and the flow rate can be stably measured even if the direction in which the tap water flows changes.

Moreover, in the measuring instrument 10, the residual chlorine sensors 30 and 30 are arranged at positions where the phase of the pipe member 11 is shifted by about 90 degrees around the axis with respect to the pair of flow measurement electrodes 22 and 22. At the same time, since the residual chlorine sensors 30 and 30 are disposed at a position that is approximately 180 degrees out of phase, for example, immediately after the residual chlorine sensor 30 to be used is switched from one to the other, the one residual chlorine sensor 30 is provided. Even if the ions generated in the flow flow to the flow sensor 20 and the other residual chlorine sensor 30 side, the ions pass through a position that is approximately 90 degrees out of phase with the flow sensor 20 and the other residual chlorine sensor. Passes through a position that is approximately 180 degrees out of phase with respect to 30. Thereby, the influence on the measurement precision of flow volume and residual chlorine concentration can be suppressed.
Since each residual chlorine sensor 30 has a structure in which the sensing electrode 33 and the base electrode 32 are integrally fixed to the sensor housing 31, the residual chlorine sensor 30 can be easily handled, and the sensing electrode 33 and the base electrode can be handled. 32 can be collectively attached to one place of the flow path.

[Second Embodiment]
This embodiment is shown in FIG. 5 and differs from the first embodiment only in the configuration of the switch control program. Hereinafter, only the configuration different from the first embodiment will be described, and the same configuration as the first embodiment will be denoted by the same reference numerals as those of the first embodiment, and redundant description will be omitted.

  When the switch control program P2 of the present embodiment is executed, the potential difference ΔV between the flow rate measurement electrodes 22 and 22 is captured (S10), and it is determined whether or not the potential difference ΔV is larger than the reference value C1 (S11). ). If the potential difference ΔV is larger than the reference value C1 (YES in S11), it is determined that tap water is flowing rightward in FIG. 1, and the DC power source 57 is switched to the first output terminal 56A side by the switch 56. Connect (S13). Thereby, when the tap water flows in the right direction in FIG. 1, only the first residual chlorine sensor 30 located on the downstream side is connected to the DC power source 57, and the second residual chlorine sensor 30 located on the upstream side is connected to the DC power source 57. Detached from.

  On the other hand, if the potential difference ΔV is not larger than the reference value C1 (NO in S11), it is determined whether or not the potential difference ΔV is smaller than the reference value −C1 (S12). If the potential difference ΔV is smaller than the reference value −C1 (YES in S12), it is determined that tap water is flowing leftward in FIG. 1, and the DC power source 57 is switched to the second output terminal 56B side by the switch 56. (S15). Thereby, when the tap water flows in the left direction in FIG. 1, only the second residual chlorine sensor 30 located on the downstream side is connected to the DC power source 57, and the first residual chlorine sensor 30 located on the upstream side is connected to the DC power source 57. Detached from.

  Further, when the potential difference ΔV is not smaller than the reference value −C1 (NO in S12), it is unclear which direction the tap water flows because the absolute value of the flow rate (flow velocity) of the tap water is small. And the switch 56 disconnects the DC power source 57 from both the output terminals 56A and 56B (S14). Thereby, both the 1st and 2nd residual chlorine sensors 30 and 30 are stopped. This makes it possible to use only the residual chlorine sensor 30 downstream of the flow sensor 20 with certainty. In the present embodiment, the above-described steps S11 and S12 constitute the “discriminating means” according to the present invention. The switch 56 and steps S13, S14, and S15 described above constitute “residual chlorine sensor switching means” according to the present invention.

[Other Embodiments]
The present invention is not limited to the above-described embodiment. For example, the embodiments described below are also included in the technical scope of the present invention, and various other than the following can be made without departing from the scope of the invention. It can be changed and implemented.

(1) In the first embodiment, the residual chlorine sensors 30, 30 are arranged in the flow path 13 with a phase shift of about 180 degrees around the axis, but as shown in FIG. 30 may be arranged in the flow path 13 in the same phase around the axis.

(2) In the first embodiment, the flow rate sensor 20 and the residual chlorine sensor 30 are attached to the pipe member 11, but in the flow rate / residual chlorine concentration measuring device according to the present invention, the flow rate sensor and the residual chlorine The member to which the sensor is attached does not necessarily have a pipe structure. For example, a configuration in which the flow sensor and the residual chlorine sensor are attached to a block-like body having a flow path through which tap water flows can be used.

(3) In the first embodiment, the silver base electrode 32 and the platinum sensing electrode 33 are provided. However, the base electrode may be silver chloride or stainless steel, and the sensing electrode may be gold or carbon.

Side sectional view of the flow rate / residual chlorine concentration measuring instrument according to the first embodiment of the present invention. Circuit diagram of flow rate and residual chlorine concentration measuring instrument Side view of residual chlorine sensor Flow chart of switch control program Flowchart of a switch control program according to the second embodiment Side view of a variation of flow rate / residual chlorine concentration measuring instrument

Explanation of symbols

10 Flow rate / residual chlorine concentration measuring instrument 11 Pipe member (body)
12 Water Pipe 13 Flow Channel 20 Electromagnetic Flow Sensor 21 Electromagnetic Coil 22 Flow Measurement Electrode 30 Residual Chlorine Sensor 31 Sensor Housing 32 Base Electrode (Residual Chlorine Concentration Measurement Electrode)
33 Sensing electrode (residual chlorine concentration measurement electrode)
56 switch (residual chlorine sensor switching means)

Claims (5)

A body with a channel through which tap water flows;
A pair of flow rate measurement electrodes disposed opposite to each other in the flow path, and a magnetic flux is applied to the flow path from a pair of electromagnetic coils opposed in a direction substantially perpendicular to the facing direction of the pair of flow rate measurement electrodes. An electromagnetic flow sensor for detecting the flow rate of the tap water based on a potential difference generated between the pair of flow measurement electrodes in a state where
A pair of residual chlorine concentration measuring electrodes arranged in the flow path, and a predetermined voltage is applied from a DC power source between the pair of residual chlorine concentration measuring electrodes during use, A flow rate / residual chlorine concentration measuring instrument comprising a residual chlorine sensor for detecting the residual chlorine concentration of the tap water based on a current flowing between the pair of residual chlorine concentration measuring electrodes via
The residual chlorine sensor is provided in pairs at two locations sandwiching the electromagnetic flow sensor in the axial direction of the flow path,
Based on the detection result of the electromagnetic flow sensor, the determination means for determining the direction in which the tap water flows and the residual chlorine sensor on the downstream side based on the determination result of the determination means, while the residual chlorine on the upstream side A flow rate / residual chlorine concentration measuring device provided with a residual chlorine sensor switching means for switching so as to stop the sensor.   2. The flow rate / residual chlorine concentration measurement according to claim 1, wherein each of the residual chlorine sensors is disposed in the flow path with a phase shift of approximately 90 degrees around an axis center with respect to the flow rate measurement electrode. vessel.   Each of the residual chlorine sensors is provided with a sensor housing in which the pair of residual chlorine concentration measuring electrodes are integrally fixed, and the body is located at a position that is substantially 180 degrees out of phase with respect to the flow path around the axis. 3. The flow rate / residual chlorine concentration measuring device according to claim 2, wherein sensor housings of both the residual chlorine sensors are fixed. The determining means is configured to determine whether the absolute value of the flow rate of the tap water is smaller than a predetermined reference value along with the direction in which the tap water flows.
The residual chlorine sensor switching means receives the determination result of the determination means, and when the absolute value of the flow rate of the tap water is smaller than a predetermined reference value, stops both the residual chlorine sensors, and the flow rate of the tap water 4. The flow rate / residual chlorine concentration measuring device according to claim 1, wherein, when the absolute value of the flow rate is greater than the reference value, switching is performed so that only the residual chlorine sensor on the downstream side is used. . The magnetic flux is applied to the water pipe, and the flow rate of the tap water flowing through the water pipe is measured using an electromagnetic flow sensor having a pair of flow measurement electrodes facing each other in the direction intersecting the magnetic flux,
Two residual chlorine sensors having a pair of residual chlorine concentration measuring electrodes are provided and arranged upstream and downstream of the electromagnetic flow sensor, and the two residual chlorine sensors are used to form the pair of residual chlorine sensors. In the tap water flow rate / residual chlorine concentration measurement method, which measures the residual chlorine concentration of tap water by performing an oxidation-reduction reaction between the electrode for concentration measurement and tap water,
Based on the detection result by the electromagnetic flow sensor, the direction of the tap water flow is determined, and the residual chlorine sensor downstream from the electromagnetic flow sensor is used according to the direction of the tap water flow at that time. On the other hand, a method for measuring the flow rate and residual chlorine concentration of tap water, wherein the residual chlorine sensor on the upstream side is switched to stop.

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