JPS59133452A - humidity detection line - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a humidity sensing line used to measure the average humidity of air within a large area.

Conventionally, various moisture detection elements have been used to measure the moisture content of air. However, these are all single-point devices, and in order to measure the average humidity of the air within a wide area, there is a problem in that a large number of them must be installed at various locations within the target area.

The present invention has been made to solve the above-mentioned problems and provide a humidity detection line suitable for measuring the average humidity of air in a wide area. Humidity sensing comprising a moisture-sensitive braided body made of hygroscopic yarn interposed between parallel electrode wires to form a humidity-sensitive line, and a core containing the humidity-sensitive line covered with a breathable protective braided body. It's on the line.

Next, the humidity sensing wire of the present invention will be explained based on the embodiment shown in FIG. The moisture-sensitive wire (3) is formed by equally twisting the wire cores, and a protective braided body (4) is further coated on the moisture-sensitive wire (3).

The parallel electrode e1m(1)(1-) may be any electrical conductor, but it is preferably one with high oxidation resistance, high corrosion resistance, and good flexibility.

The humidity-sensitive braided body (2) (2") should preferably have electrical properties such as dielectric constant, dielectric power factor, insulation resistance, and impedance that change as linearly as possible in response to changes in air humidity, and have little hysteresis. Therefore, it is preferable that the moisture-absorbing yarn constituting the moisture-sensitive braided body be one that easily absorbs and releases moisture.If the measurement range is wide from low humidity to high humidity, yarns that are naturally low in moisture absorption should be used. Synthetic fibers such as polyester spun into a structure that easily absorbs moisture, such as multifilament yarn or spun yarn, are preferred, but natural fibers with high hygroscopicity are suitable for mainly measuring low humidity. The protective braided body (4) has good breathability;
Preference is given to those made from non-hygroscopic threads.

The above is a moisture sensitive wire (3) made by combining two wire cores in a balanced type.
As shown in Fig. 2, a moisture-sensitive braided body (2) is provided on the inner electrode wire (1), and a coaxial and air-permeable outer electrode wire (1) is placed on top of the moisture-sensitive braided body (2). ') to form a moisture sensitive line (3) is also included in the present invention.

In this case, the internal electrode wire (1) may be the same as the electrode wire in the embodiment of FIG. It is formed by winding metal tape vertically or in layers, or by winding a metal tape in gaps.

Furthermore, as shown in Fig. 3, in addition to the above-mentioned moisture-sensitive wire, there is also a wire core made by equally twisting two wire cores in which the conductor (5) (5') is coated with the insulator (6) (6'). The present invention also includes a core formed including the temperature measurement line (7).

The conductor (5) (5M) may be any metal wire that can be used as an electric conductor, but it is desirable to have good flexibility and a large rate of change in conductor resistance with temperature, that is, a large temperature coefficient.

3- Insulator (6) Any flexible insulator can be used for (6), but if condensation occurs, it is possible to dry it by heating the temperature measurement wire with electricity. , those with good water resistance and heat resistance are preferred.

Before making measurements, obtain a reference curve in advance.

That is, the humidity detection wire of the present invention is placed in a constant temperature and humidity chamber, and at each temperature, the capacitance and dielectric power factor between the parallel electrode wires (1) and (1-) are measured with respect to changes in relative humidity (%). , insulation resistance, impedance, etc. were measured, and these were measured using the parallel electrode wire (1) (per unit length of 1M).The horizontal axis represents the relative temperature (%), and the vertical axis represents the above electrical characteristic values. Draw a diagram of the plot.

Next, the humidity detection wire of the present invention is laid at an appropriate location within the target area to be measured, and the capacitance, dielectric power factor, insulation resistance, impedance, etc. between the parallel electrode wires are measured, and the measured values are The relative humidity is determined by converting the value per unit length of the parallel electrode wires (1) and (1') and comparing the converted value with the above reference curve.

It is clear that the relative humidity measurements obtained as described above are indicative of the average humidity of the area where the humidity detection line was installed.

Furthermore, in the case of a device equipped with a temperature measuring wire, if the terminal end of the temperature measuring wire is short-circuited and a reference curve is obtained in advance for the reciprocating conductor resistance value seen from the starting end, as in the case of the moisture sensitive wire described above, it is possible to compare it with the reference curve. The comparison allows the average temperature within the installation area to be determined.

The relationship between relative humidity (%) and electrical characteristic values in the humidity detection line of the present invention was tested for one example, and the details and results are as follows.

<Example> As a parallel electrode wire, a wire core 2 was prepared by using a bundle of 30 0.18 mm annealed copper wires and braiding 2 threads of 250 denier Tetron (trade name) with 12 strokes.
A humidity sensing wire was made by twisting the books together to form a sensing wire, and covering the wire with a protective braided body having two 250 denier Tetoron yarns and 24 strokes.

A comparative example was also prepared in which the moisture-sensitive braided body had two 200-denier polyethylene monofilament yarns and a 12-stroke braiding break.

<Test method> Approximately 7 IOm of trial yield was collected from the above examples and comparative examples, and the sample was made into a coil with a diameter of approximately 300 m, and suspended in a constant temperature and humidity tank with an internal volume of 1.8 m. The temperature was kept at 30°C, the relative humidity was gradually increased, and a 60H
7 AC voltage (V) is applied, and the reference impedance (
By measuring the voltage (VO) that appears across both ends of 7o), the impedance between the electrodes of the temperature sensing wire is determined by the following formula. (Test results) The test results are shown in Figure 5, and the comparative example is shown in curve (A). As shown, the impedance finally begins to decrease when the relative humidity exceeds 11J180%, but in the example song M (B)
As shown in Fig. 7, the impedance between the electrodes decreases linearly from the low humidity region to the high humidity region as the relative humidity changes, so the accuracy of humidity measurement can be said to be extremely good.

As described above, the use of the humidity detection line of the present invention has the advantage that the average humidity in a wide area can be measured extremely easily with one detection line.

In addition, if a device equipped with a temperature measurement line is used, the temperature within the area can also be measured, making it even more effective for environmental control.

[Brief explanation of the drawing]

1 to 3 are cross-sectional views of embodiments of the present invention. FIG. 4 is a circuit diagram for measuring interelectrode impedance of a humidity detection line. FIG. 5 is a comparison diagram of moisture sensitivity characteristics of an example of the present invention and a comparative example. 1.1- Electrode wire 2 Moisture sensitive braided body 3
Moisture-sensing wire 4 Protective braided body 5.5- Temperature measuring conductor 6.6- Insulator 7 Temperature measuring wire Patent applicant Tatsuta Electric Wire Co., Ltd. Representative Takeo Oishi 8- Toru 4 Kokusei] h (%) Patent Agency Commissioner Kazuo Wakasugi 2. Name of the invention Humidity detection line 3, Relationship with the case of the person making the amendment Patent applicant April 26, 1988 Supplement 336-

Claims (1)

[Claims] 1) A moisture-sensitive braid made of hygroscopic yarn is interposed between a pair of parallel electrode wires to form a moisture-sensitive line, and a core containing the moisture-sensitive line is ventilated. Humidity detection wire covered with a flexible protective braid. 2) Humidity detection according to claim 1, characterized in that the humidity-sensitive wire is formed by equally twisting together two wire cores in which a humidity-sensitive braided body made of hygroscopic thread is provided on the electrode wire. line. 3) Claims characterized in that the moisture-sensitive wire comprises a moisture-sensitive braided body layer made of hygroscopic yarn on the inner electrode wire, and a coaxial and air-permeable outer electrode wire thereon. Humidity detection line described in item 1. 4) Claims 1, 2, or 3, characterized in that the core includes a moisture-measuring wire made by equally twisting two wire cores each having a conductor coated with an insulator. Humidity detection line described in section.