Measurement instrument, measurement device, measurement system, and measurement method

Abstract

This measurement instrument comprises: a cell that has an inner wall surface and houses a measurement fluid; a first electrode that has a detection surface that comes into contact with the measurement fluid in the cell; a measurement fluid introduction section that extends toward the cell from above at an angle on the opposite side of the bottom end of the inner wall surface from the first electrode, and that introduces the measurement fluid into the cell; and cleaning beads that clean the detection surface by moving along the inner wall surface with the flow of the measurement fluid introduced from the measurement fluid introduction section.

Description

Measuring meter, measuring device, measuring system, and measuring method

[0001] The present application relates to a measurement meter, a measurement device, a measurement system, and a measurement method.

[0002] A known method for measuring residual chlorine contained in a fluid is the polarographic method, in which a voltage is applied between two electrodes (a working electrode and a counter electrode) immersed in the fluid and the current flowing between the two electrodes is measured to measure the concentration of residual chlorine (see, for example, Patent Document 1 listed below).

[0003] In measuring residual chlorine by polarography, the surface of the electrode becomes contaminated after a certain period of use. Therefore, in Patent Document 1, cleaning beads are passed through the electrode together with the fluid to clean the electrode.

[0004] However, in Patent Document 1, an inlet channel for introducing a fluid into the cell is connected tangentially to the bottom end of the annular cell, which poses a problem that, for example, washing beads tend to flow out of the inlet channel when the inside of the cell is washed.

[0005] Japanese Patent No. 4153459

[0006] Therefore, an object is to provide a measuring meter, a measuring device, a measuring system, and a measuring method that can prevent cleaning beads for cleaning electrodes from flowing out of a cell.

[0007] The measuring meter comprises: a cell having an inner wall surface and containing a measurement fluid; a first electrode having a detection surface that comes into contact with the measurement fluid in the cell; a measurement fluid inlet portion that extends from diagonally above the opposite side of the first electrode toward the cell, sandwiching the lower end of the inner wall surface, and that introduces the measurement fluid into the cell; and cleaning beads that move along the inner wall surface with the flow of the measurement fluid introduced from the measurement fluid inlet portion, and clean the detection surface.

[0008] The measuring device comprises the measuring meter and a main body to which the measuring meter is detachably attached.

[0009] The measurement system includes the measurement device and a communication device capable of communicating with the measurement device.

[0010] The measurement method uses a measuring instrument that includes: a cell having an inner wall surface and containing a measurement fluid; a first electrode having a detection surface that comes into contact with the measurement fluid in the cell; a measurement fluid inlet portion that extends from diagonally above the opposite side of the first electrode toward the cell, sandwiching the lower end of the inner wall surface, and that introduces the measurement fluid into the cell; and cleaning beads that move along the inner wall surface with the flow of the measurement fluid introduced from the measurement fluid inlet portion, and clean the detection surface.

[0011] FIG. 8 is an overall schematic diagram of a measurement system according to one embodiment; FIG. 9 is an overall schematic diagram of a measurement system according to the embodiment, showing a state in which one measurement meter is removed from the main body; FIG. 10 is a diagram showing a fluid flow path in a measurement device according to the embodiment; FIG. 11 is a control block diagram of a measurement system according to the embodiment; FIG. 12 is a control block diagram of a measurement system according to the embodiment;

[0012] An embodiment of a measurement system, a measurement device, and a measurement meter will be described below with reference to Figures 1 to 12. Note that in each figure, the dimensional ratios in the drawing do not necessarily match the actual dimensional ratios, and the dimensional ratios between the drawings do not necessarily match.

[0013] 1 and 2, a measurement system 101 may include, for example, a measurement device 102 that measures a fluid, and a communication device 103 that can communicate with the measurement device 102 via communication means X1. Note that the fluid is not particularly limited and includes, for example, not only liquids but also gases, mixtures of liquids and gases, mixtures of liquids and solids, etc.

[0014] Although not particularly limited, the communication device 103 may be, for example, a mobile terminal (for example, a smart device, a tablet computer, a notebook PC, etc.) as in this embodiment. The communication means X1 may be, for example, a wireless communication means such as Wi-Fi or a wireless LAN, or may be, for example, a wired communication means such as a communication cable or a wired LAN.

[0015] The measuring device 102 may include, for example, a plurality of (five in this embodiment) measuring meters 104 for measuring fluid, and a main body 105 to which each measuring meter 104 is detachably attached. The number of measuring meters 104 is not particularly limited, and may be, for example, one, two to four, or six or more.

[0016] The measuring meter 104 is not particularly limited as long as it is an instrument that measures values ​​related to the fluid (e.g., characteristic values, state values, etc.). For example, if the measuring meter 104 is a water quality meter that measures values ​​related to water, the measuring meter 104 may be, for example, a turbidity meter, a color meter, a pH meter, a residual chlorine concentration meter, a conductivity meter, a flow meter, a water temperature meter, etc. Note that the multiple measuring meters 104 may each measure different values ​​related to the fluid.

[0017] 3, the measuring device 102 may include, for example, an inlet 102a into which a fluid flows, an outlet 102b from which the fluid flows, and a flow path 102c through which the fluid flows from the inlet 102a to the outlet 102b, as in this embodiment. Although not shown, the measuring device 102 may include a structure that allows a fluid (e.g., a chemical solution for cleaning, a calibration solution for calibration, etc.) different from the fluid to be measured (e.g., water) to flow through the flow path 102c.

[0018] Also, for example, as in this embodiment, the measuring device 104 may have a measurement flow path 104a through which a fluid flows, the main body 105 may have a main body flow path 105a through which a fluid flows, and the measurement flow path 104a and the main body flow path 105a may form the flow path 102c. Then, by attaching the measuring device 104 to the main body 105, the measurement flow path 104a and the main body flow path 105a may be connected to each other to form the flow path 102c.

[0019] 4, the measuring meter 104 and the main body 105 may each include, for example, measuring units 104b and 105b that measure the fluid. The measuring device 102 (specifically, each measuring meter 104 and main body 105) and the communication device 103 may each include, for example, input units 103c, 104c, and 105c to which various data are input, and output units 103d, 104d, and 105d to which various data are output, as in this embodiment.

[0020] Furthermore, the measuring device 102 (specifically, each measuring meter 104 and main body 105) and the communication device 103 may, for example, as in this embodiment, be equipped with acquisition units 103e, 104e, 105e that acquire various data, memory units 103f, 104f, 105f that store various data, calculation units 103g, 104g, 105g that calculate the various data, and control units 103h, 104h, 105h that control the devices 102 (104, 105) and 103 based on the various data.

[0021] As shown in FIG. 5, the measuring device 102 (specifically, each measuring meter 104 and main body 105) and the communication device 103 may be equipped with a computer having processors 103i, 104i, 105i such as a CPU and an MPU (e.g., calculation units 103g, 104g, 105g, control units 103h, 104h, 105h), memories 103j, 104j, 105j such as a ROM and RAM (e.g., acquisition units 103e, 104e, 105e, storage units 103f, 104f, 105f), various interfaces 104k, 105k, 103k (e.g., acquisition units 103e, 104e, 105e), etc.

[0022] Then, the processors 103i, 104i, 105i execute the programs 103m, 104m, 105m stored in the memories 103j, 104j, 105j, and the software and hardware work together to realize the calculation units 103g, 104g, 105g and control units 103h, 104h, 105h of the measuring device 102 (specifically, each measuring meter 104 and main body 105) and the communication device 103.

[0023] Figure 6 is a perspective view of a measuring instrument 1, which is one of the multiple measuring instruments 104 shown in Figures 1 and 2. As shown in Figure 6, the measuring instrument 1 is formed in a generally rectangular parallelepiped shape that is elongated in the vertical direction D3. In the following description, the direction in which the inlet pipe 81 and the outlet pipe 82 (described later) are arranged side by side is referred to as the second horizontal direction D2, and the direction perpendicular to the second horizontal direction D2 and the vertical direction D3 is referred to as the first horizontal direction D1. The measuring instrument 1 includes a measuring unit 1a and a case 1b and a cover 1c that surround the measuring unit 1a.

[0024] Fig. 7 is a perspective view showing the measurement unit 1a with the case 1b and cover 1c removed, and Fig. 8 is a side view of the measurement unit 1a. The measurement unit 1a comprises a base 8 connected to the main body 105 and a measurement unit main body 9 fixed to the base 8.

[0025] The measurement unit main body 9 comprises a first main body portion 91 that is rectangular when viewed from the front, a second main body portion 92 that is L-shaped when viewed from the front and is joined to the first main body portion 91, and a flow path forming portion 93 that is connected to the second main body portion 92.

[0026] Fig. 9 is a cross-sectional view of the measurement unit 1a shown in Fig. 8 taken along line IX-IX. Fig. 10 is a cross-sectional view of the measurement unit 1a shown in Fig. 8 taken along line XX. The measurement unit 1a includes a cell 2, a first electrode 3, a measurement fluid inlet 4, and washing beads 5.

[0027] Fig. 11 is an enlarged view of region XI in Fig. 9. For ease of explanation, the washing beads 5 are not shown in Fig. 11. Fig. 12 is an enlarged view of region XI in Fig. 9, and the flow of the measurement fluid is indicated by dotted arrows.

[0028] The cell 2 contains a fluid to be measured (hereinafter referred to as the measurement fluid). The cell 2 is formed at the interface between the first body portion 91 and the second body portion 92. The cell 2 has an annular inner wall surface 20 with a central axis CL extending in the first horizontal direction D1. In this specification, the term "annular" does not necessarily mean a perfectly circular cross section, but may also mean a substantially circular cross section. For example, an elliptical cross section is also included in the term "annular." Furthermore, for example, a circular shape with a radius varying by approximately 10% is also included in the term "annular." In the case of a substantially circular cross section, the central axis CL is set at the center of the maximum width of the inner wall surface 20 in the vertical direction D3 and the center of the maximum width in the second horizontal direction D2. The distance from the central axis CL to the inner wall surface 20 is, for example, 5 to 20 mm.

[0029] The inner wall surface 20 has a first side wall surface 21 located on one side of the central axis CL in the second lateral direction D2, and a second side wall surface 22 located on the other side of the central axis CL in the second lateral direction D2. The first side wall surface 21 is the bottom surface of a semicircular recess formed in the side surface of the first main body portion 91. The second side wall surface 22 is the bottom surface of a semicircular recess formed in the side surface of the second main body portion 92. In other words, the inner wall surface 20 can be separated into the first side wall surface 21 and the second side wall surface 22 by disassembling the first main body portion 91 and the second main body portion 92.

[0030] The first side wall surface 21 has a detection opening 21a formed at the same height as the central axis CL. The detection opening 21a being at the same height as the central axis CL means that the center of the detection opening 21a is at the same height as the central axis CL. A first electrode installation portion 21b is connected to the detection opening 21a. The first electrode installation portion 21b is formed to extend in the second lateral direction D2 and penetrate the first main body portion 91. The first electrode installation portion 21b houses the first electrode 3.

[0031] The second side wall surface 22 has an inlet 22a formed below the central axis CL and above the lower end of the second side wall surface 22. The measurement fluid inlet 4 is connected to the inlet 22a.

[0032] The second side wall surface 22 has an outlet 22b formed above the central axis CL. The outlet 22b is connected to the measurement fluid outlet portion 6.

[0033] The first electrode 3 is a working electrode. The tip of the first electrode 3 has a detection surface 3a that comes into contact with the measurement fluid in the cell 2. The detection surface 3a is made of gold or platinum. The detection surface 3a is exposed to the cell 2 through a detection port 21a.

[0034] The detection surface 3a contacts a virtual first side wall surface 21 (shown by a two-dot chain line in FIG. 11 ) that would exist if the detection port 21a and the first electrode installation portion 21b were not formed. As shown in FIG. 11 , the detection port 21a is closer to the central axis CL than the detection surface 3a. As a result, a buffer space surrounded by the first electrode installation portion 21b is formed between the detection port 21a and the detection surface 3a. By providing this buffer space, when the cleaning beads 5 clean the detection surface 3a as described below, the cleaning beads 5 remain in the buffer space, allowing the detection surface 3a to be effectively polished by a large number of cleaning beads 5.

[0035] The first electrode 3 is housed in a first body 91. The first body 91 also houses a second electrode 7, a reference electrode 71, and an EC electrode 72 (see FIGS. 8 and 10). The second electrode 7 is a counter electrode. The detection surface of the second electrode 7 is made of plated silver. The reference electrode 71 contacts the measured fluid and outputs a reference potential. The EC electrode 72 is a temperature sensor.

[0036] The measurement-fluid inlet 4 is formed so as to penetrate the second main body 92. The measurement-fluid inlet 4 extends obliquely from above toward the cell 2. More specifically, the measurement-fluid inlet 4 extends linearly in a direction sloping downward toward the inlet 22a. Preferably, the measurement-fluid inlet 4 extends in a tangential direction of the annular inner wall surface 20. In this embodiment, the cross section of the measurement-fluid inlet 4 is a circle with a diameter of 1.2 mm.

[0037] The measurement fluid inlet 4 communicates with a first introduction flow path 41 formed in the flow path forming portion 93. The first introduction flow path 41 is formed in a substantially C-shape in side view as shown in Fig. 9. One end of the first introduction flow path 41 is connected to the measurement fluid inlet 4, and the other end is connected to a second introduction flow path 42 formed in the second main body portion 92. The second introduction flow path 42 communicates with an introduction pipe 81 (described later) via an introduction flow path (not shown).

[0038] A filter 43 is disposed at the connection between one end of the first inlet flow path 41 and the measurement fluid inlet section 4, i.e., at the interface between the flow path forming section 93 and the second main body section 92. Similarly, a filter 43 is disposed at the connection between the other end of the first inlet flow path 41 and the second inlet flow path 42, i.e., at the interface between the flow path forming section 93 and the second main body section 92. By disposing the filter 43 at the interface between the flow path forming section 93 and the second main body section 92, the filter 43 can be easily replaced.

[0039] The cleaning beads 5 are mainly contained in the cell 2 together with the measurement fluid. The cleaning beads 5 are made of ceramic or glass. The cleaning beads 5 move along the inner wall surface 20 of the cell 2 due to the flow of the measurement fluid introduced from the measurement fluid inlet 4 (indicated by the dotted arrow in FIG. 12 ), and come into sliding contact with the detection surface 3 a, thereby polishing and cleaning the detection surface 3 a. At this time, the cleaning beads 5 come into contact with the detection surface 3 a from a direction substantially parallel to or slightly inclined relative to the detection surface 3 a, thereby preventing the cleaning beads 5 from excessively polishing the detection surface 3 a.

[0040] The measurement fluid outlet 6 extends upward from the outlet 22b of the cell 2. The measurement fluid outlet 6 is formed by a recess formed in the side surface of the second main body 92 and the side surface of the first main body 91. The measurement fluid outlet 6 leads the measurement fluid in the cell 2 to a discharge flow path 60 (see FIG. 10 ). The measurement fluid outlet 6 has a discharge port 6d formed in the upper wall, and the discharge flow path 60 is connected to this discharge port 6d.

[0041] The measurement-fluid outlet 6 has an enlarged portion 6a whose cross-sectional area expands upward. The enlarged portion 6a is formed by inclining the side wall 6b on the second main body 92 side so that it moves away from the side wall 6c (the side surface of the first main body 91) on the first main body 91 side as it extends upward. That is, the cross-sectional area of ​​the enlarged portion 6a expands in the second horizontal direction D2. The enlarged portion 6a may be formed so that its cross-sectional area expands not only in the second horizontal direction D2 but also in the first horizontal direction D1. The measurement-fluid outlet 6 has an enlarged portion 6a, so that its cross-sectional area is significantly larger than that of the measurement-fluid inlet 4. This significantly reduces the flow rate of the measurement fluid introduced from the measurement-fluid inlet 4 in the measurement-fluid outlet 6. This prevents the washing beads 5 from moving to the measurement-fluid outlet 6 along with the measurement fluid.

[0042] A second electrode 7 is provided on the side wall 6c of the measurement fluid lead-out portion 6. A protrusion 61 is provided on the side wall 6c of the measurement fluid lead-out portion 6 below the second electrode 7. By providing the protrusion 61 below the second electrode 7, even if the cleaning beads 5 move to the measurement fluid lead-out portion 6, the cleaning beads 5 can be prevented from contacting and polishing the detection surface at the tip of the second electrode 7.

[0043] The protrusion 61 is formed so that the lower surface 61a is inclined upward toward the tip. The lower surface 61a of the protrusion 61 is inclined in the same direction as the side wall 6b of the measurement fluid lead-out portion 6 with respect to the vertical direction D3. This ensures a sufficient flow path for the measurement fluid, thereby preventing the protrusion 61 from impairing the flow of the measurement fluid.

[0044] The base 8 has an inlet pipe 81 and an outlet pipe 82 connected to the main body 105 on its bottom surface. The inlet pipe 81 and the outlet pipe 82 are arranged side by side in the second horizontal direction D2. The measurement unit main body 9 is attached to the base 8. The base 8 has an inlet flow path (not shown) that connects the inlet pipe 81 to the second inlet flow path 42 of the measurement unit main body 9. The base 8 also has an outlet flow path (not shown) that connects the outlet pipe 82 to the outlet flow path 60 of the measurement unit main body 9.

[0045] As described above, the measurement unit main body 9 includes a first main body 91, a second main body 92, and a flow path forming portion 93. Electrodes including a first electrode 3, a second electrode 7, etc. are arranged in the first main body 91, and flow paths including a measurement fluid inlet 4, a measurement fluid outlet 6, and a discharge flow path 60 are formed in the second main body 92. This allows the flow paths to be easily cleaned with a chemical solution by disassembling the first main body 91 and the second main body 92 during maintenance of the measurement meter 1. Furthermore, disassembling the first main body 91 and the second main body 92 allows the electrodes and cleaning beads 5 to be easily replaced.

[0046] As described above, the measurement system 101 according to this embodiment includes the measurement device 102 and the communication device 103 that can communicate with the measurement device 102 .

[0047] As in this embodiment, the measuring device 102 includes a measuring meter 104 and a main body 105 to which the measuring meter 104 is detachably attached.

[0048] As in this embodiment, the measuring meter 1 comprises a cell 2 having an inner wall surface 20 and containing a measurement fluid, a first electrode 3 having a detection surface 3 a that comes into contact with the measurement fluid in the cell 2, a measurement fluid inlet 4 that extends from diagonally above the opposite side of the first electrode 3 across the lower end of the inner wall surface 20 toward the cell 20 and introduces the measurement fluid into the cell 20, and cleaning beads 5 that move along the inner wall surface 20 with the flow of the measurement fluid introduced from the measurement fluid inlet 4 and clean the detection surface 3 a.

[0049] According to this configuration, the measurement fluid inlet 4 extends obliquely from above and is connected to the cell 2 , so that the washing beads 5 can be prevented from flowing out of the cell 2 .

[0050] Furthermore, as in this embodiment, it is preferable that the inner wall surface 20 be formed in an annular shape with the central axis CL extending in the first lateral direction D1.

[0051] With this configuration, the cleaning beads 5 can move smoothly along the inner wall surface 20 .

[0052] In addition, as in this embodiment, it is preferable that the first electrode 3 extends toward the central axis CL.

[0053] With this configuration, the detection surface 3 a of the first electrode 3 is parallel to the tangential direction of the inner wall surface 20 (first side wall surface 21). As a result, the cleaning beads 5 come into contact with the detection surface 3 a in a direction substantially parallel to or slightly inclined relative to the detection surface 3 a, thereby preventing the cleaning beads 5 from excessively polishing the detection surface 3 a.

[0054] Furthermore, as in this embodiment, the inner wall surface 20 has a first side wall surface 21 located on one side of the central axis CL in a second horizontal direction D2 perpendicular to the first horizontal direction D1, and a second side wall surface 22 located on the other side of the central axis CL in the second horizontal direction D2, and the first side wall surface 21 has a detection port 21a formed at the same height as the central axis CL and exposing the detection surface 3a, and the second side wall surface 22 has an inlet port 22a formed below the central axis CL and above the lower end of the second side wall surface 22 and connected to the measurement fluid inlet portion 4.

[0055] According to this configuration, the inlet 22a connected to the measurement fluid inlet 4 is formed above the lower end of the second side wall surface 22, thereby preventing the cleaning beads 5 for cleaning the first electrode 3 from flowing out of the cell 2.

[0056] In addition, as in this embodiment, it is preferable that the measurement fluid inlet portion 4 extends in a direction inclined downward toward the inlet 22a.

[0057] With this configuration, the direction in which the measurement fluid inlet 4 extends approaches the tangential direction of the annular inner wall surface 20, so that the flow of the measurement fluid introduced from the measurement fluid inlet 4 makes it easier for the cleaning beads 5 to move along the inner wall surface 20.

[0058] Furthermore, as in this embodiment, it is preferable that the detection port 21a is closer to the central axis CL than the detection surface 3a.

[0059] With this configuration, when the cleaning beads 5 clean the detection surface 3a, the cleaning beads 5 remain in the buffer space between the detection port 21a and the detection surface 3a, so that the detection surface 3a can be effectively polished by a large number of cleaning beads 5.

[0060] Furthermore, as in this embodiment, it is preferable to have a configuration including a measurement fluid derivation section 6 extending upward from a derivation outlet 22b formed above the central axis CL of the second side wall surface 22, a second electrode 7 provided on a side wall 6c of the measurement fluid derivation section 6, and a protrusion 61 provided on the side wall 6c of the measurement fluid derivation section 6 below the second electrode 7.

[0061] With this configuration, even if the cleaning beads 5 move to the measurement fluid lead-out portion 6, the cleaning beads 5 can be prevented from contacting and polishing the detection surface at the tip of the second electrode 7.

[0062] Furthermore, as in this embodiment, it is preferable that the measurement fluid lead-out portion 6 has an enlarged portion 6a whose cross-sectional area increases upward.

[0063] With this configuration, the flow rate of the measurement fluid introduced from the measurement fluid inlet 4 is significantly reduced in the measurement fluid outlet 6, thereby preventing the washing beads 5 from moving to the measurement fluid outlet 6 along with the measurement fluid.

[0064] In addition, as in this embodiment, it is preferable that the lower surface 61a of the projection 61 be configured to be inclined upward toward the tip.

[0065] With this configuration, it is possible to prevent the protrusions 61 from impairing the flow of the fluid to be measured.

[0066] Furthermore, as in this embodiment, it is preferable that the cleaning beads 5 are made of ceramic or glass.

[0067] With this configuration, the detection surface 3 a of the first electrode 3 can be effectively polished and cleaned by the cleaning beads 5 .

[0068] Furthermore, as in this embodiment, it is preferable to have a configuration that includes a first main body portion 91 having a first side wall surface 21 formed thereon and a second main body portion 92 having a second side wall surface 22 formed thereon, and that the first main body portion 91 and the second main body portion 92 are disassembled.

[0069] Such a configuration makes maintenance of the measuring instrument 1 easy.

[0070] The measurement system 101, the measurement device 102, and the measurement meter 1 are not limited to the configurations of the above-described embodiments, and are not limited to the above-described effects. Furthermore, the measurement system 101, the measurement device 102, and the measurement meter 1 can be modified in various ways without departing from the spirit of the present invention. For example, it is possible to arbitrarily select one or more of the configurations, methods, etc. of the various modified examples described below and adopt them in the configurations, methods, etc. of the above-described embodiments.

[0071] (1) In the measuring meter 1 according to the above embodiment, the protrusion 61 provided on the side wall 6 c of the measurement fluid outlet portion 6 is configured to be located below the second electrode 7 and above the reference electrode 71. However, the measuring meter 1 is not limited to this configuration. For example, the protrusion 61 may be configured to be located below the second electrode 7 and the reference electrode 71. With this configuration, even if the cleaning beads 5 move to the measurement fluid outlet portion 6, the cleaning beads 5 can be prevented from contacting and polishing the detection surface at the tip of the reference electrode 71.

[0072] (2) In the measuring instrument 1 according to the above embodiment, the inner wall surface 20 of the cell 2 is configured to have a circular ring shape with the central axis CL extending in the first horizontal direction D1. However, the measuring instrument 1 is not limited to this configuration. The inner wall surface 20 may be configured to have a ring shape with a polygonal cross section, such as a hexagonal or octagonal cross section.

[0073] (3) In the measuring instrument 1 according to the above embodiment, the first electrode 3 extends toward the central axis CL. However, the measuring instrument 1 is not limited to this configuration. The first electrode 3 does not necessarily have to extend toward the central axis CL, in other words, along the radial direction of the cell 2, but may extend at an angle to the radial direction of the cell 2.

[0074] (4) The measuring instrument 1 according to the above embodiment includes a first main body 91 having a first side wall surface 21 and a second main body 92 having a second side wall surface 22, and the first main body 91 and the second main body 92 are separable. However, the measuring instrument 1 is not limited to this configuration. The measuring unit main body 9 may be configured such that the first main body 91 and the second main body 92 are integrally formed.

[0075] (5) In the measuring meter 1 according to the above embodiment, a flow path formed directly in the measuring unit main body 9 is given as an example of a measurement fluid inlet. However, the measuring meter 1 is not limited to this configuration. The measurement fluid inlet may be nozzle-shaped and inserted into a through-hole formed in the measuring unit main body 9 so as to extend obliquely from above toward the cell 2. In this case, the tip of the nozzle-shaped measurement fluid inlet may be positioned inside the cell 2 beyond the inlet 22a of the cell 2.

[0076] (6) In the measuring instrument 1 according to the above embodiment, the direction in which the inlet pipe 71 and the outlet pipe 72 are arranged side by side is defined as the second horizontal direction D2, and the direction perpendicular to the second horizontal direction D2 and the up-down direction D3 is defined as the first horizontal direction D1. However, this is not limiting. For example, the direction in which the inlet pipe 71 and the outlet pipe 72 are arranged side by side may also be defined as the first horizontal direction D1. Furthermore, the first horizontal direction D1 or the second horizontal direction D2 does not need to be parallel to the direction in which the inlet pipe 71 and the outlet pipe 72 are arranged side by side.

[0077] (7) As shown in FIG. 13 , the measuring device 102 may include a first solenoid valve 102d provided on the main flow path 105a immediately after the inlet port 102a and a second solenoid valve 102e provided on the main flow path 105a immediately before the outlet port 102b. These valves are controlled by a control unit 105h. During fluid measurement, the first solenoid valve 102d and the second solenoid valve 102e allow the measurement fluid to flow in through the inlet port 102a and out through the outlet port 102b, as shown by the arrows in FIG. 13 . The first solenoid valve 102d is a three-way valve, one end of which is connected to a drain port 102f. By switching the first solenoid valve 102d, the flow path 102c can be connected to the drain port 102f, allowing the measurement fluid in the flow path 102c to be discharged from the drain port 102f. The second solenoid valve 102e is also a three-way valve, one end of which is connected to an atmospheric opening 102g. The atmosphere opening 102g is located at the top of the main body 105. By switching the second solenoid valve 102e, the flow path 102c can be connected to the atmosphere opening 102g, thereby opening the flow path 102c to the atmosphere. Incidentally, when the measurement fluid is introduced into the measuring meter 1 from a state where no measurement fluid is contained (an empty state) at the start of measurement, washing beads 5 may reach the outlet 6d along with the measurement fluid, as shown in FIG. 14 . At this time, the outlet 6d is covered with a mesh 6e to prevent the washing beads 5 from being discharged from the outlet 6d, but the washing beads 5 may stick to this mesh 6e. If the washing beads 5 stick to the mesh 6e, the measurement fluid is less likely to be discharged from the outlet 6d, reducing the measurement efficiency, or the number of washing beads 5 in the cell 2 is reduced, resulting in a reduced cleaning effect. Therefore, the measurement method may include a step of temporarily stopping the introduction of the measurement fluid from the measurement fluid inlet 4 into the cell 2, or temporarily causing the measurement fluid to flow backward from the cell 2 to the measurement fluid inlet 4. Specifically, by temporarily switching the first solenoid valve 102d and the second solenoid valve 102e (for example, for 1 to 2 seconds) to connect the flow path 102c to the drain port 102f and the atmosphere opening 102g, the measurement fluid flows toward the drain port 102f, as shown by the arrows in Fig. 15. This prevents the measurement fluid from being introduced into the cell 2 from the measurement fluid inlet 4, or causes the measurement fluid to flow back from the cell 2 to the measurement fluid inlet 4.As a result, the cleaning beads 5 adhering to the mesh 6e naturally fall into the cell 5, thereby preventing a decrease in measurement efficiency and cleaning effect. Thereafter, the first solenoid valve 102d and the second solenoid valve 102e are switched over as shown in FIG. 13 to measure the measurement fluid.

[0078] REFERENCE SIGNS LIST 1... measuring meter, 1a... measuring unit, 1b... case, 1c... cover, 2... cell, 3... first electrode, 3a... detection surface, 4... measurement fluid inlet, 5... washing beads, 6... measurement fluid outlet, 6a... expansion section, 6b... side wall of measurement fluid outlet, 6c... side wall of measurement fluid outlet, 6d... outlet, 6e... mesh, 7... second electrode, 8... base, 9... measurement unit main body, 20... inner wall surface, 21... first side wall surface, 21a... detection port, 21b... first electrode installation section, 22... second side wall surface, 22a... inlet, 2 2b...outlet port, 41...first inlet flow path, 42...second inlet flow path, 43...filter, 60...exhaust flow path, 61...protrusion, 61a...underside of protrusion, 71...reference electrode, 72...EC electrode, 81...inlet pipe, 82...exhaust pipe, 91...first main body portion, 92...second main body portion, 93...flow path forming portion, 101...measurement system, 102...measurement device, 102a...inlet portion, 102b...outlet portion, 102c...flow path, 102d...first solenoid valve, 102e...second solenoid valve, 102f...drain port, 10 2g...atmospheric opening, 103...communication device, 103c...input section, 103d...output section, 103e...acquisition section, 103f...storage section, 103g...calculation section, 103h...control section, 103i...processor, 103j...memory, 103k...interface, 103m...program, 104...measuring meter, 104a...measurement flow path, 104b...measurement section, 104c...input section, 104d...output section, 104e...acquisition section, 104f...storage section, 104g...calculation section, 104h...control section, 10 4i...processor, 104j...memory, 104k...interface, 104m...program, 105...main body, 105a...main body flow path, 105c...input unit, 105d...output unit, 105e...acquisition unit, 105f...storage unit, 105g...calculation unit, 105h...control unit, 105i...processor, 105j...memory, 105k...interface, 105m...program, CL...central axis, D1...first horizontal direction, D2...second horizontal direction, D3...vertical direction, X1...communication means

Claims

1. a cell having an inner wall surface and containing a measurement fluid; a first electrode having a detection surface in contact with the measurement fluid in the cell; a measurement fluid inlet extending from diagonally above the lower end of the inner wall surface on the opposite side of the first electrode toward the cell, and introducing a measurement fluid into the cell; a measuring instrument comprising: cleaning beads that move along the inner wall surface by the flow of the measurement fluid introduced from the measurement fluid inlet portion and clean the detection surface.

2. The measurement instrument according to claim 1 , wherein the inner wall surface is formed in an annular shape with a central axis extending in the first horizontal direction.

3. The measurement meter of claim 2 , wherein the first electrode extends toward the central axis.

4. the inner wall surface has a first side wall surface located on one side of the central axis in a second horizontal direction perpendicular to the first horizontal direction, and a second side wall surface located on the other side of the central axis in the second horizontal direction, the first side wall surface has a detection opening formed at the same height as the central axis and exposing the detection surface; The measuring meter according to claim 2 or 3, wherein the second side wall surface has an inlet formed below the central axis and above a lower end of the second side wall surface, the inlet being connected to the measurement fluid inlet portion.

5. The measurement meter according to claim 4 , wherein the detection port is closer to the central axis than the detection surface.

6. a measurement fluid outlet portion extending upward from an outlet formed above the central axis of the second side wall surface; a second electrode provided on a side wall of the measurement fluid outlet portion; The measurement meter according to claim 4 , further comprising: a protrusion provided on a side wall of the measurement fluid outlet portion below the second electrode.

7. The measurement meter according to claim 6 , wherein the measurement fluid outlet portion has an enlarged portion whose cross-sectional area increases upward.

8. The measurement meter of claim 6 , wherein the lower surface of the projection slopes upward toward the tip.

9. 4. The measuring instrument according to claim 1, wherein the cleaning beads are made of ceramic or glass.

10. a first body portion on which the first side wall surface is formed, and a second body portion on which the second side wall surface is formed, The measurement meter according to claim 4 , wherein the first body portion and the second body portion are separable.

11. A measuring instrument according to any one of claims 1 to 3; a main body to which the measuring meter is detachably attached.

12. The measuring device according to claim 11; a communication device capable of communicating with the measurement device;

13. a cell having an inner wall surface and containing a measurement fluid; a first electrode having a detection surface in contact with the measurement fluid in the cell; a measurement fluid inlet extending from diagonally above the lower end of the inner wall surface on the opposite side of the first electrode toward the cell, and introducing a measurement fluid into the cell; a measuring method using a measuring instrument including cleaning beads that move along the inner wall surface with the flow of the measurement fluid introduced from the measurement fluid inlet portion and clean the detection surface;

14. 14. The measurement method according to claim 13, further comprising the step of temporarily stopping the introduction of the measurement fluid from the measurement fluid inlet into the cell, or temporarily causing the measurement fluid to flow backward from the cell to the measurement fluid inlet.