JP3205469U - Water level sensor, water level meter, conductivity sensor - Google Patents

Abstract

A water level sensor is provided that can easily change the water level to be detected and can also detect a plurality of water levels satisfactorily. An opening 12 for exposing the liquid surface is provided in the housing 10 and electrode terminals are provided to the housing so that a part of the electrode terminals 30 and 40 are exposed in the opening, so that the liquid level varies. The housing can be moved with respect to the provided support pillars PA and PB. The water level to be detected can be easily changed. By providing a plurality of water level sensors 100, a plurality of water levels can be detected well. Furthermore, since the liquid level is detected in the opening provided in the housing, the water level can be detected well even under a situation where the liquid level is rippled. Moreover, it can utilize also as a sensor which measures the electrical conductivity of a liquid. [Selection] Figure 1

Description

  The present invention relates to a water level sensor that measures the level of a liquid, a water level meter that uses the water level sensor, and an improvement in an electrical conductivity sensor that measures conductivity.

  As a conventional water level sensor and water level meter, for example, there is one disclosed in Patent Document 1 below. The first electrode rod for detecting the water level is suspended in the water tank so that the lower end thereof is located at the height of the water level to be detected, and the second electrode rod can be contacted with water at the bottom of the water tank. The water level in the water tank is detected based on the energized state between the first and second electrode rods. On the other hand, as a conventional conductivity sensor, for example, Patent Document 2 below discloses a similar electrode rod shape.

Japanese Utility Model Publication No. 7-38923 JP 2003-294666 A

  By the way, in the background art of Patent Document 1 described above, when changing the water level to be detected, it is necessary to adjust the length of the first electrode rod. In addition, when detecting a plurality of water levels, it is necessary to prepare a plurality of the first electrode rods. Furthermore, there is a disadvantage that the water level cannot be measured satisfactorily under a situation where waves are generated on the water surface.

  The present invention focuses on the above points, and its purpose is to easily change the water level to be detected. Another object is to detect a plurality of water levels satisfactorily. Yet another object is to detect the water level well even under conditions where the water surface is rippled. Yet another object is to use a water level sensor or a water level meter to measure conductivity.

  The water level sensor of the present invention is a water level sensor that detects the position of the liquid level from a change in the resistance value between the electrode terminals, and provided with an opening through which the liquid level is exposed in a housing that holds the electrode terminal. The electrode terminal is provided on the housing so that a part of the electrode terminal is exposed to the opening. One of the main forms is characterized in that the connecting portion between the electrode terminal and the lead-out coated wire is sealed with a heat-shrinkable resin. One of the other forms is characterized in that an insertion hole for inserting the electrode terminal is provided in the housing, and a chemical-resistant resin is filled between the insertion hole and the electrode terminal.

  The water level meter of the present invention is a water level meter that detects the position of the liquid level using any one of the water level sensors, provided with a support column in the direction of fluctuation of the liquid level, It is characterized in that the casing is provided so as to be movable. One of the main forms is characterized in that the water level sensors are provided on the support column at positions of a plurality of liquid levels to be detected.

  The conductivity sensor of the present invention is a conductivity sensor that detects the conductivity of a liquid from a change in resistance value between electrode terminals, and an opening that fills the liquid is provided in a housing that holds the electrode terminals. In addition, the electrode terminal is provided on the casing so that a part of the electrode terminal is exposed to the opening. One of the main forms is characterized in that the connecting portion between the electrode terminal and the lead-out coated wire is sealed with a heat-shrinkable resin. One of the other forms is characterized in that an insertion hole for inserting the electrode terminal is provided in the housing, and a chemical-resistant resin is filled between the insertion hole and the electrode terminal.

  The conductivity meter according to the present invention is a conductivity meter that detects the conductivity of a liquid using any one of the conductivity sensors, wherein a support column is provided in the liquid, and the conductivity sensor is provided in the liquid. The conductivity sensor is provided on the support column such that the support column is submerged. The above and other objects, features, and advantages of the present invention will become apparent from the following detailed description and the accompanying drawings.

  According to the present invention, the housing is provided with an opening through which the liquid level is exposed, and the electrode terminal is provided with respect to the housing so that a part of the pair of electrode terminals is exposed through the opening. Since the housing can be moved with respect to the support column provided in the changing direction, the water level to be detected can be easily changed. Moreover, a plurality of water level sensors can be satisfactorily detected by providing a plurality of water level sensors. Furthermore, since the liquid level is detected in the opening provided in the housing, the water level can be detected well even under a situation where the liquid level is rippled. In addition, since the distance between the electrode terminals is constant, it is possible to measure the resistance value between the electrode terminals by measuring the resistance value between the electrode terminals.

It is the perspective view and top view which show the structure of Example 1 of this invention. It is explanatory drawing which shows the structure of the connection part in the said Example 1, and the mode of an assembly. It is explanatory drawing which shows the example of installation of the said Example 1. FIG. It is a perspective view which shows the structure of Example 2 of this invention.

  Hereinafter, the best mode for carrying out the present invention will be described in detail based on examples.

  First, Embodiment 1 of the present invention will be described with reference to FIGS. Example 1 shows the most basic structure. FIG. 1 shows a water level sensor according to the present invention, in which (A) is a perspective view and (B) is a plan view. In these drawings, the water level sensor 100 has a configuration in which electrode terminals 30 and 40 are provided on a housing 10 formed entirely by a rectangular plate having a thickness. More specifically, a circular opening 12 is formed at the center of the housing 10, and through holes 14 and 16 are formed at the corners in the direction of the arrow FA that is the thickness direction. In the example shown in the figure, two through holes 14 and 16 are provided, but one or more may be provided. Furthermore, insertion holes 20 and 22 are provided in the housing 10 substantially in parallel in the direction of the arrow FB perpendicular to the thickness direction.

  The support holes PA and PB provided in the vertical direction in the liquid container for measuring the water level pass through the through holes 14 and 16 of the housing 10. Can be positioned. On the other hand, electrode terminals 30 and 40 are inserted into the insertion holes 20 and 22 of the housing 10, respectively, and a part of them is exposed at the opening 12 at the center of the housing 10.

  The electrode terminals 30 and 40 are connected to covered wires 32 and 42 for electrical connection to the outside by connecting portions 31 and 41, respectively. The connection parts 31 and 41 have a structure manufactured by the procedure as shown in FIG. 2, for example. As shown in FIG. 1A, first, connecting pipes 34 and 44 formed of a material that can be easily soldered such as copper and brass are prepared, and the end portions of the electrode terminals 30 and 40 are press-fitted into the connecting pipes 34 and 44. Fit. At this time, the press-fitting amounts of the electrode terminals 30 and 40 are set so that concave portions are formed in the connection pipes 34 and 44. In the illustrated example, the press-fitting amount is about half of the length of the connecting pipes 34 and 44. In this state, as shown in FIG. 5B, an AC or DC power source EW is connected between the end portions of the electrode terminals 30 and 40 and energized to connect to the electrode terminals 30 and 40. The pipes 34 and 44 are electrically welded, and both are electrically and mechanically connected.

  Next, as shown in FIG. 3C, the leading end portions of the coverings 32A and 42A of the covering wires 32 and 42 are removed to expose the conducting wires 32B and 42B. Then, as shown in FIG. 4D, the conducting wires 32B and 42B are inserted into the connecting pipes 34 and 44, or pressed against the ends of the electrode terminals 30 and 40, and the conducting wires are connected within the connecting pipes 34 and 44. The 32B and 42B are soldered to the electrode terminals 30 and 40 and the connecting pipes 34 and 44 (see HD in FIGS. 2D and 2E).

  Next, as shown in FIG. 5E, the entire connecting portion is covered with heat-shrinkable resin tubes 36 and 46, and heat is applied from the outside to heat-shrink the resin tubes 36 and 46. By doing in this way, as shown to the same figure (F), a connection part can be sealed with the resin tubes 36 and 46. FIG. In addition, you may use as the resin tubes 36 and 46 what applied the adhesive agent inside.

  The electrode terminals 30 and 40 in which the connection portions 31 and 41 with the covered wires 32 and 42 are formed in this way are inserted into the insertion holes 20 and 22 of the housing 10 as shown in FIG. At this time, if necessary, the caps 38 and 48 are inserted from the covered wires 32 and 42 side so as to close the openings of the insertion holes 20 and 22. Further, if necessary, a chemical-resistant resin is filled and fixed between the insertion holes 20 and 22 and the electrode terminals 30 and 40, and then the caps 38 and 48 are used to insert the insertion holes 20 and 22. The opening may be closed. By doing in this way, fixation of the electrode terminals 30 and 40 with respect to the housing | casing 10 can be strengthened. An appropriate voltage is applied to the electrode terminals 30 and 40 from the outside. When the liquid contacts the electrode terminals 30 and 40, the resistance value between them changes. By detecting this, it is detected that the water level has become the electrode terminal position.

  FIG. 3 shows an installation example of the water level sensor 100 configured as described above. As shown in the figure, support pillars PA and PB are suspended from a base body 112 in a container 110 in which a liquid W for measuring a water level is accommodated. As the support columns PA and PB, for example, insulating materials are used. In the water level sensor 100, the through holes 14 and 16 of the casing 10 are penetrated by the support columns PA and PB, and are screwed at a water level to be measured. In the illustrated example, three water level sensors 100A, 100B, and 100C are provided and fixed at the positions of the water levels LA, LB, and LC, respectively. The three water level sensors 100A, 100B, and 100C may be arranged apart from each other as shown in FIG. 10A, or may be arranged close to each other as shown in FIG.

  The electrode terminals 3 and 40 of the water level sensors 100A, 100B, and 100C are connected to the detection circuit 120 by covered wires 32 and 42. Various known circuits may be used as the detection circuit 120. For example, an input / output separation circuit disclosed in Utility Model Registration No. 3198437 is suitable.

  As a material of each part such as the casing 10 constituting the water level sensor 100, a material that does not deteriorate due to the liquid to be immersed is used. For example, if the liquid is acidic, a material having acid resistance is used.

  Next, the operation of this embodiment will be described. Assuming a case where the liquid W is injected into the container 110 and the liquid level gradually rises, the water level does not reach any of the water levels LA, LB, LC at the beginning, so the water level sensors 100A, 100B, In any of 100C, the resistance between the electrode terminals 30 and 40 is high. When the liquid level of the liquid W rises and reaches the water level LA, the resistance value between the electrode terminals 30 and 40 of the water level sensor 100A decreases by the liquid W. By detecting this, it can be known that the liquid level has become the water level LA. Similarly, it can be detected that the liquid level has become the water levels LB and LC from the decrease in the resistance value of the water level sensor 100B and the decrease in the resistance value of the water level sensor 100C, respectively.

  By the way, the water level sensors 100A, 100B, 100C are all movable in the direction of the support pillars PA, PB, and the number of the water level sensors 100A, 100B, 100C can be increased or decreased. Accordingly, the position and number of water levels to be detected can be arbitrarily and easily changed. Further, since the housing 10 acts just like a breakwater, fluctuations in the liquid level are suppressed in the opening 12 where the electrode terminals 30 and 40 are exposed. For this reason, even if the liquid surface of the liquid W has a wave, stable water level measurement can be performed.

  Next, Embodiment 2 of the present invention will be described with reference to FIG. In the first embodiment described above, the electrode terminals 30 and 40 are drawn from the same direction (the same side surface of the housing 10) by the covered wires 32 and 42, but in this embodiment, the electrode terminals 30 and 40 are drawn from the opposite direction. That is, the covered wire 32 of the electrode terminal 30 is drawn from one side surface of the housing 10, and the covered wire 42 of the electrode terminal 40 is drawn from the opposite side surface.

In addition, this invention is not limited to the Example mentioned above, A various change can be added in the range which does not deviate from the summary of this invention. For example, the following are also included.
(1) The shape and structure of each part shown in the above embodiment can be changed in design so as to achieve the same effect. For example, the opening 12 of the housing 10 is formed in an ellipse or oval shape that is long in the direction of the electrode terminals 30 and 40, and the exposure area of the electrode terminals 30 and 40 to the opening 12 is increased, so that the liquid level changes according to the liquid level. The amount of change in resistance value can be increased.
(2) In the above embodiment, the support columns PA and PB are suspended, but they may be erected in the liquid layer, not limited to the vertical direction, but in an oblique direction along the shape of the liquid layer It is good. In this case, the through holes 14 and 16 are provided obliquely with respect to the housing 10.
(3) Although the present invention is an example in which the present invention is used as a water level sensor or a water level meter, it can also be used as an electrical conductivity sensor for measuring the electrical conductivity of a liquid. As described above, the distance between the electrode terminals 30 and 40 is held constant by the housing 10. For this reason, when the electrode terminals 30 and 40 are in contact with the liquid, not only the water level but also the resistance value between the terminals can be known from the degree of voltage and current between the two, and the electric conductivity of the liquid can be determined from the result. I can know. Also when used as an electric power sensor, the housing 10 is fixed by the support columns PA and PB as shown in FIG. 3, but the sensor itself is submerged in the liquid. Thus, the present invention can be applied to the conductivity sensor.
(4) Also, a support column is provided in the liquid, and the conductivity sensor is provided in the support column so that the conductivity sensor is submerged in the liquid. For example, the input / output disclosed in Utility Model Registration No. 3198437 By combining with a separate amplifier, it can be used as a simple conductivity meter.
(5) The present invention can be applied to various liquids other than water.

  According to the present invention, it is possible to easily change the water level to be detected, and it is also suitable for detecting a plurality of water levels, and it is possible to measure the water level well even in a situation where the water surface is rippled. Therefore, it is suitable for water level measurement in containers and tanks in which various liquids are stored. It is also suitable for measuring the electrical conductivity of liquid.

10: Housing 12: Opening 14, 16: Through hole 20, 22: Insertion hole 30, 40: Electrode terminal 31, 41: Connection portion 32, 42: Covered wire 32A, 42A: Covered 32B, 42B: Conductor wires 34, 44 : Connection pipe 36, 46: Resin tube 38, 48: Cap 100, 100A, 100B, 100C: Water level sensor 110: Container 112: Base body 120: Detection circuit EW: Power supply HD: Solder LA, LB, LC: Water level PA, PB : Support column W: Liquid

Claims (8)

A water level sensor that detects the position of the liquid level from a change in resistance value between the electrode terminals,
While providing an opening through which the liquid level is exposed in a housing that holds the electrode terminal,
The water level sensor, wherein the electrode terminal is provided to the casing so that a part of the electrode terminal is exposed to the opening.   The water level sensor according to claim 1, wherein a connection portion between the electrode terminal and the lead-out coated wire is sealed with a heat-shrinkable resin.   The water level sensor according to claim 1 or 2, wherein an insertion hole for inserting the electrode terminal is provided in the casing, and a chemical-resistant resin is filled between the insertion hole and the electrode terminal. . A water level meter that detects the position of the liquid level using the water level sensor according to any one of claims 1 to 3,
A water level meter, wherein a support column is provided in the direction of fluctuation of the liquid level, and the housing is provided to be movable with respect to the support column.   5. The water level meter according to claim 4, wherein the water level sensor is provided on the support column at a plurality of liquid level positions to be detected. An electrical conductivity sensor that detects the electrical conductivity of a liquid from a change in resistance value between electrode terminals,
While providing an opening filled with the liquid in a housing holding the electrode terminal,
The conductivity sensor according to claim 1, wherein the electrode terminal is provided on the casing so that a part of the electrode terminal is exposed to the opening.   7. The conductivity sensor according to claim 6, wherein a connection portion between the electrode terminal and the lead-out covered wire is sealed with a heat-shrinkable resin.   The electrical conductivity according to claim 6 or 7, wherein an insertion hole for inserting the electrode terminal is provided in the housing, and a chemical-resistant resin is filled between the insertion hole and the electrode terminal. Sensor.

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