JP2856360B2 - Electrode device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an electrode device for measuring water quality such as pH and OPR using a measurement electrode and a reference electrode. The present invention relates to an electrode device suitable for measuring water quality of lakes, marshes, groundwater, and the like by a casting method.

[Conventional technology]

Conventionally, pH and various other ion concentrations have been measured using measurement electrodes such as a glass electrode and an ion-selective electrode. It is necessary to have a liquid junction and to allow the internal liquid to always flow out of the electrode from this liquid junction for electrical connection with the test liquid.

By the way, an electrode device for measuring water quality using the measurement electrode and the reference electrode described above includes a process measurement electrode device in which only the tip detection unit is immersed in the test water to perform the measurement, and an entire device in the ocean or the sea. There is a projection type electrode device that performs measurement by submerging in a river or the like. In this case, as the outflow means of the above-mentioned internal liquid, a method of pressurizing with compressed air to flow out in the electrode device for process measurement, a method of flowing out by head pressure, and the like are employed. In the pneumatic system, these systems are difficult to adopt because the equipment becomes large, and when the water depth becomes deep, high pressure is required, which is dangerous, and the head pressure system has a limit on the measurable water depth.

For this reason, in the injection type electrode device, a method of closing the internal liquid supply port of the comparative electrode and allowing the internal liquid to flow out by diffusion has conventionally been used as the internal liquid outflow means, and an internal part partitioned by a rubber diaphragm for pressure balance. A method of connecting a liquid tank to a reference electrode and supplying an internal liquid from the tank to the reference electrode is usually adopted. It has also been proposed to arrange a piston in a cylindrical internal liquid supply tank connected to the reference electrode, and to supply the internal liquid to the reference electrode by pressing force of the piston by pressing the piston with a spring. (Japanese Utility Model Laid-Open No. 57-16964).

[Problems to be solved by the invention]

However, in the conventional injection type electrode device, in the diffusion type in which the above-described supply port is simply closed, the internal liquid is diffused and the test liquid flows back into the electrode through the liquid junction. There is a disadvantage that accurate measurement cannot be performed. In the case of the rubber diaphragm type, the pressure is balanced according to the water depth. However, once the pressure is balanced, the outflow of the internal liquid is still caused by diffusion, and therefore the same problem as described above occurs. Furthermore, in the case of a piston type using a spring, the test liquid flows into the electrode when the water pressure at the measurement point is higher than the pressing force of the spring, and is not suitable for deep measurement. For this reason, it has been difficult for the conventional immersion electrode device to stably measure the water quality in deep places such as the sea and river for a long time.

The present invention has been made in view of the above circumstances, and can always make the pressure of the internal liquid higher than the pressure of the test liquid irrespective of the absolute pressure of the test liquid. However, it is possible to prevent the test liquid from flowing back into the electrode and to always allow the test liquid to flow out of the liquid junction, so that an electrode device capable of performing accurate water quality measurement stably for a long period of time is required. Aim to influence.

[Means for solving the problem]

In order to achieve the above object, the present invention provides, as a first invention, a state in which a measurement electrode and a comparison electrode are provided, and an internal liquid in the comparison electrode is continuously discharged from a liquid junction of the comparison electrode to the outside. In an electrode device for measuring water quality, a telescopic diaphragm is disposed inside a vertical cylindrical cylinder so as to cover the passage, and a weight is attached to the diaphragm so as to be movable up and down, and the inside of the cylinder is separated by the diaphragm. An inner part which is liquid-tightly divided into an upper chamber and a lower chamber, and which forms a test liquid passage which communicates the upper chamber with the outside world in the cylinder, and which communicates from the lower chamber with an internal liquid replenishing port of a comparison electrode. With a liquid passage,
There is provided an electrode device wherein the internal liquid injected into the lower chamber is pressurized by the pressing force of the weight so that the internal liquid is supplied to the comparison electrode through the internal liquid passage.

Further, the present invention, as a second invention, has a measurement electrode and a reference electrode, and measures water quality in a state where the internal liquid in the reference electrode is continuously discharged from the liquid junction of the reference electrode to the outside. In the electrode device to be performed, a weight is disposed inside a vertical cylindrical cylinder so as to cover the passage so as to be movable up and down and liquid-tight with respect to the cylinder wall. And liquid-tightly divided into a liquid passage and forming a test liquid passage communicating the upper chamber and the outside world with the cylinder, and providing an internal liquid passage communicating from the lower chamber to an internal liquid replenishment port of the comparison electrode. An internal liquid injected into the lower chamber by a pressing force of the weight, whereby the internal liquid is supplied to the comparison electrode through the internal liquid passage. .

(Operation)

The device of the first invention of the present application fills the lower chamber with the internal liquid,
The diaphragm and the weight are submerged in a state of being pushed upward. In this case, the test liquid flows into the upper chamber through the test liquid passage, so that the pressure in the upper chamber and the pressure in the lower chamber are in equilibrium through the diaphragm according to the water depth, and the self-pressure balance is improved. However, in this apparatus, since the weight is attached to the diaphragm, the pressure inside the lower chamber is increased by the weight of the weight in addition to the pressure balance. Therefore, due to the pressure increased by this weight, the pressure applied to the internal liquid is maintained higher than the external test liquid regardless of the water depth pressure, so that the internal liquid always flows out of the liquid junction. In addition, a stable measurement is performed without the test liquid flowing back into the internal liquid.

The device according to the second aspect of the present invention fills the lower chamber with the internal liquid and submerges the weight in a state where the weight is pushed upward. In this case, assuming that the frictional resistance and the weight of the weight provided vertically movable and liquid-tight in the cylinder are zero, the pressure in the upper chamber and the pressure in the lower chamber become the same as in the first invention. The pressure in the lower chamber is increased by the weight of the weight in addition to the pressure balance in the present apparatus. Therefore, due to the pressure increased by this weight, the pressure applied to the internal liquid is maintained higher than the external test liquid regardless of the water depth pressure.
The internal liquid always flows out of the liquid junction, and stable measurement is performed without the test liquid flowing back into the internal liquid.

Next, the present invention will be described in detail with reference to examples, but the present invention is not limited to the following examples.

Embodiment 1 FIG. 1 shows an electrode device according to an embodiment of the present invention.

In the figure, reference numeral 1 denotes a composite electrode in which a glass electrode and a comparative electrode are integrated. This electrode 1 has a liquid junction 3 near an electrode film 2 provided at the lower end thereof, and potassium chloride near an upper end cap 4. It has a solution replenishing port 5.

Reference numeral 6 denotes a cylindrical electrode membrane protection cylinder having a ring-shaped partition wall 7 at the upper part of the inner peripheral surface, and the side wall thereof has a predetermined number (three in this embodiment) of flow holes 8. A spiral groove 9 is formed on the inner peripheral surface of the protective cylinder 6 above the partition wall, and a spiral groove 11 formed at the lower end of a cylindrical outer cylinder 10 is formed in the spiral groove 9. The composite electrode 1 is detachably screwed, and the composite electrode 1 is disposed inside the protective cylinder 6 and the outer cylinder 10. Reference numeral 12 denotes a ring-shaped washer, and 13 denotes a ring-shaped tapered packing. By arranging the packing 13, the inside of the protection cylinder 6 where the liquid junction 3 is located and the potassium chloride solution replenishing port 5
The communication with the inside of the outer cylinder 10 where is located is blocked.

Reference numeral 14 denotes a transparent or translucent synthetic resin-made bottomed cylindrical cylinder having a relatively thick bottom wall 15, for example, a small-diameter hole 16 at the center of the bottom wall 14 and a large-diameter hole at the bottom. The holes 17 are formed continuously and the large-diameter holes
A spiral groove 19 formed at the upper end of the outer cylinder 10 is liquid-tightly and detachably separated by an O-ring 20 in a spiral groove 18 formed on the inner wall of the outer cylinder 10. Are in communication with each other. Reference numeral 21 denotes a lock nut.

A spiral groove 22 is formed on the outer periphery of the upper end of the cylinder 14, and a spiral groove 24 formed on the inner peripheral surface of a headed cylindrical lid 23 made of synthetic resin such as polypropylene is screwed into the spiral groove 22. ing.

Further, reference numeral 25 denotes a lead wire lead-out hole formed in the bottom wall 15 of the cylinder 14 along the radial direction, which communicates with the small-diameter hole 16, and a lead wire 26 drawn from the electrode 1 is connected to the small-diameter hole 16. The measurement result is displayed or recorded by being drawn out of the drawing hole 25 through the drawing hole 25 and connected to, for example, a converter or the like.
The liquid tightness is maintained between 26 by a packing 27 and a fastener 28.

Here, in the present apparatus, the lower side of the wall of the cylinder 14 is formed to be thick, and the wall of the cylinder 14 is cut along the radial direction at the thick part 14a, whereby the cylinder 14 is moved upward. It is divided into 14b and lower part 14c. Between the lower end of the upper portion 14b and the upper end of the lower portion 14c, an outer peripheral edge of a lower end of an elastic bellows-like diaphragm 29 made of chloroprene rubber or the like is sandwiched. A substantially cylindrical weight 30 having a weight of about 500 to 1500 g is vertically movably attached so as to close the portion, whereby the inside of the cylinder 14 is liquid-tightly divided into an upper chamber 31a and a lower chamber 31b by a diaphragm 29. I have. The weight 30 is obtained by coating the surface of the metal part 30a with a synthetic resin layer 30b for corrosion prevention. Reference numeral 32 denotes a nut for pressing and fixing the upper portion 14b to the lower portion 14c of the cylinder 14, and reference numeral 33 denotes a ring-shaped fastener for attaching the weight 30 to the diaphragm 29 in a liquid-tight manner. Further, in the present apparatus, a pair of circular test liquid passages 34, 34 are formed in the wall of the upper chamber 14b of the cylinder 14, thereby communicating the upper chamber 31b and the outside world.

When measuring the pH of the sea or the like using this apparatus, first, the internal liquid is filled in the lower chamber 31b of the cylinder 31 and the outer cylinder 10, and the diaphragm 29 is extended and the weight 30 is completely raised. The internal liquid can be injected from the lower end opening of the outer cylinder 10 by removing the protective cylinder 6 and the packing 13. Then, in this state, the entire apparatus is submerged in water and measurement is performed. As described above, the internal liquid in the lower chamber 31b is added to the pressure balance and the pressure is increased by the weight of the weight 30, and this is increased. Due to the pressure, the internal liquid flows from the lower chamber 31b through the outer cylinder 10 into the electrode 1 through the replenishing port 5, and constantly flows out of the liquid junction 3, thereby preventing the test liquid from flowing backward.

Embodiment 2 FIG. 2 shows an electrode device according to another embodiment of the present invention.
In FIG. 2, the same components as those of the apparatus of FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted.

In the present apparatus, a cylindrical weight 30 is disposed in the cylinder 14 so as to be movable up and down by a pair of ring packings 35 and 35 in a liquid-tight manner with respect to the wall of the cylinder 14 so as to cover the passage. Further, a columnar stopper 23a is protrudingly provided at the center of the lower surface of the lid 23 so as not to block the test liquid passages 34 when the weight 30 is raised.

When performing measurement using this apparatus, first, the internal liquid is filled in the lower chamber 31b of the cylinder 31 and the outer cylinder 10, and the weight 3
Set the state where 0 has been reached. Then, in this state, the entire apparatus is submerged in water and measurement is performed. As described above, the internal liquid in the lower chamber 31b is added to the pressure balance and the pressure is increased by the weight of the weight 30, and this is increased. The internal liquid constantly flows out of the liquid junction 3 due to the pressure, and the backflow of the test liquid is prevented.

Embodiments 3 to 6 FIGS. 3 to 6 show still another embodiment of the present invention. 3 to 6, the same components as those of the apparatus shown in FIGS. 1 and 2 are denoted by the same reference numerals, and the description thereof will be omitted.

The apparatus shown in FIGS. 3 and 4 is provided with an internal liquid inflow path 36 whose peripheral wall is formed of resin along the longitudinal direction at the center of the weight 30 of the apparatus shown in FIGS. 1 and 2, and the upper end of the weight 30. Is connected to a resin-made internal liquid injection pipe 37 whose inside communicates with the inflow path 36, and a hole 23 formed by drilling the upper part of the pipe 37 in the lid 23.
b, and the upper end opening is covered with lid 38 and packing 39.
The internal liquid can be injected into the lower chamber 31b from the upper end opening of the pipe 37 through the pipe 37 and the internal liquid inflow passage 36. The method of using this apparatus is the same as that of the apparatus shown in FIGS.

In the apparatus shown in FIG. 5, the outer periphery of the upper end of the bellows-like diaphragm 29 is sandwiched and fixed between the upper end of the cylinder 14 and the lid 23, and the opening is closed at the lower end of the diaphragm 29. A columnar weight 30 is attached so as to be vertically movable, whereby the inside of the diaphragm 29 is configured as an upper chamber 31a and the outside of the diaphragm 29 is configured as a lower chamber 31b. In the present apparatus, a test liquid passage 34 is formed in the lid 23. Further, in order to prevent deformation of the diaphragm 29, a hard ring-shaped member 40 is provided at a large diameter portion of the diaphragm 29.

When the measurement is performed by the present apparatus, the lower chamber 31b and the outer cylinder 10 are filled with the internal liquid, the diaphragm 29 is contracted, and the weight 30 is completely raised, and then the water is submerged. The upper chamber 31a expands, and the lower chamber 3
A pressure is applied to the internal liquid of 1b, and the internal liquid constantly flows out of the liquid junction 3 due to this pressure.

The device shown in FIG. 6 is a device in which the cylinder 14 and the electrode 1 of the device shown in FIG. 5 are separated, and these are connected by a flexible internal liquid flow pipe 41 therebetween. 42 is a plate-like member with an O-ring for closing the lower end opening of the cylinder 14, 43 is a nut for fixing the plate-like member 42, 44 is a plate-like member 42.
The internal liquid injection hole 45 formed in the injection hole 45 is a stopper for closing the injection hole 44.
The internal liquid can be injected into the lower chamber 31b from 44.

In this device, the internal liquid in the lower chamber 31b flows into the electrode 1 through the internal liquid flow pipe 41, and flows out of the liquid junction 3.

In the above embodiment, the glass electrode 1 for pH measurement was used for the detection unit, but the present invention is not limited to this. An ion electrode or the like can be used, and a composite electrode is used as the electrode 1. And the measurement electrode may be separated. Also,
The apparatus of the above embodiment is mainly used for throwing, but the test liquid flowing through the flow path during the process is transferred to the upper chamber 31a.
It can also be used for process measurement by balancing the pressure in the flow path and the pressure in the lower chamber 31b. Further, a rubber film or the like having a plate-like elasticity may be used as the diaphragm 29 instead of a bellows-like one, and the cylinder 14 and the electrode 1 of the apparatus shown in FIGS. The other configurations may be variously changed without departing from the gist of the present invention.

〔The invention's effect〕

As described above, according to the present invention, the internal liquid is pressurized by the urging pressure of the weight regardless of the external test liquid pressure due to the water depth or the like. The internal liquid always flows out from the liquid junction to ensure stable electrical connection, and since the test liquid from the outside does not enter the internal liquid side, there is no deterioration of the internal liquid, so it is stable even in deep places for a long time The measurement can be performed at the same time.

[Brief description of the drawings]

1 to 6 are cross-sectional views showing one embodiment of the present invention. 1 Composite electrode 2 Liquid junction 5 Refill port 14 Cylinder 29 Diaphragm 30 Weight 31a Upper chamber 31b Lower chamber 34 Test liquid passage

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A 2-101258 (JP, U) JP-A 57-16964 (JP, U) (58) Fields surveyed (Int. Cl. ⁶ , DB name) G01N 27/30

Claims (2)

(57) [Claims] An electrode device having a measurement electrode and a reference electrode, wherein water quality is measured in a state in which an internal liquid in the reference electrode is continuously discharged from a liquid junction of the reference electrode to the outside world.
An elastic diaphragm is provided inside the vertical cylindrical cylinder so as to cover the passage, and a weight is vertically movably attached to the diaphragm so that the inside of the cylinder is liquid-tight with the diaphragm into an upper chamber and a lower chamber. A divided test passage is formed in the cylinder to communicate the upper chamber with the outside world, and an internal liquid passage communicating from the lower chamber to the internal liquid supply port of the comparison electrode is provided. An electrode device, wherein the internal liquid injected into the lower chamber is pressurized by pressure to supply the internal liquid to the comparison electrode through the internal liquid passage. 2. An electrode device having a measurement electrode and a reference electrode, wherein water quality is measured in a state where an internal liquid in the reference electrode is continuously discharged from a liquid junction of the reference electrode to the outside.
The weight is divided up into an upper chamber and a lower chamber by arranging the weight vertically up and down and covering the cylinder wall in a liquid-tight manner by covering the passage inside the vertical cylindrical cylinder. A test liquid passage communicating the upper chamber with the outside world, and an internal liquid passage communicating from the lower chamber to an internal liquid replenishment port of the comparison electrode. An electrode device, wherein the internal liquid injected into the lower chamber is pressurized by pressure to supply the internal liquid to the comparison electrode through the internal liquid passage.