JPH09257284A - Humidity controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a small, compact and highly accurate humidity controller by providing vertically a humidifying tank for producing humidified air below a saturating tank for supplying saturated air to a testing tank. SOLUTION: A humidifying tank 9 is provided vertically in series below a testing tank 5 and a saturating tank 2. The temperature T0 of the humidifying tank 9 is detected by a temperature sensor 71 and the temperature T2 (= room temperature T1) of the saturating tank 2 or the testing tank 5 is detected by a temperature sensor 72 provided in a high heat conductor 1 and both temperatures T0 and T2 are inputted to a control means 7. The control means 7 controls a power E supplied to a heater 70 by an operating end 8 so that the temperature T0 of the humidifying tank 9 detected by the temperature sensor 71 is a little higher than the room temperature T2 detected by the temperature sensor 72 (T0>T2). Thus, a hygrometer or the like is inserted into the space 50 of the testing tank 5 to correct the hygrometer. Thus, a small, compact and highly accurate humidity generator can be obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a humidity generator that generates humidity for calibrating a hygrometer.

[0002]

2. Description of the Related Art A humidity generator used to calibrate a hygrometer uses a shunt type of mixing saturated air and dry air in a saturated tank, or the temperature of a saturated tank in which water vapor is saturated, A two-temperature method, a two-pressure method, a two-temperature two-pressure method that generates a predetermined humidity by using the ratio of the pressure and the temperature of the measurement / test tank to obtain the desired humidity and the pressure. There is.

In the split-flow method, it is difficult to ensure the accuracy of the mixing ratio of saturated air and dry air, and in the 2-temperature method and 2-pressure method, the temperature difference of 0.1 ° C. is 1% RH in humidity. ,
In the two-temperature method, it is necessary to precisely maintain the temperatures of the saturated tank and the test tank, and it takes time to change the temperature of the tank. In the two-pressure method, the pressure can be switched, so the response is Fast, but usually requires a large constant temperature bath.

That is, a saturated tank (saturator, saturation device) or the like for obtaining constant-temperature and constant-humidity saturated air from the humidified air from the humidifying tank is used as such a humidity generator. Are usually supplied to the test tank, but normally, the saturation tank and the test tank are installed in a large water temperature tank to obtain a desired saturated air or the like at a constant temperature (for these points, JIS Z8806- 1981, B7920-
1994, etc.).

[0005]

However, when such a water temperature tank is used, it is necessary to control the temperature of the entire water temperature tank, the heat capacity of the controlled object is large, the control is difficult, and a uniform temperature distribution is obtained. Since it is necessary to stir the entire water temperature tank, it is difficult to evaluate the temperature distribution, and the equipment and auxiliary equipment are large and complicated.

In view of the above points, an object of the present invention is to provide a small-sized, compact, highly accurate humidity generator having a simple structure.

[0007]

According to the present invention, in a humidity generator in which a test tank and a saturated tank are integrated, humidified air is generated below the saturated tank for supplying saturated air to the test tank. This is a humidity generator in which a humidifying tank is provided vertically.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a humidity generator for calibrating a hygrometer by the two-pressure method showing an embodiment of the present invention.

In the figure, a humidifying tank 9 is arranged below the test tank 5 and the saturation tank 2 in series vertically and vertically. The humidifying tank 9 is, for example, a bubbling tank, and the air A that contains the water W and is introduced from the lower portion by a compressor or the like and pressurized is bubbled in the water W from the porous sintered metal 91 or the like to be almost saturated. The near humidified humidified air Ao is introduced into the lower portion of the saturation tank 2 through the pipe 92.

The saturation tank 2 is provided below the inside of the high thermal conductor 1 such as a metal block of aluminum, copper or the like having good thermal conductivity, and the test tank 5 is provided above the inside of the high thermal conductor 1. They are integrally provided in series vertically. That is,
The saturation tank 2 and the test tank 5 are integrally formed in the high thermal conductor 1 by, for example, hollowing or close contact.
This saturation tank 2 forms a closed space inside the high thermal conductor 1,
The bottom of the inner space is made into a basin shape for containing water W,
With a structure in which the air A0 introduced from the lower portion passes through the surface of the water W, sufficient saturated air A1 having a temperature T1 and a pressure P1 of 100% RH is taken from the outside. In addition. The thermal conductivity of aluminum and copper constituting the high thermal conductor 1 is about 420 that of water.
~ 720 times, very high thermal conductivity, 0.1 as a whole
Soaking property within ℃ is easily obtained.

The saturated air A1 from the saturation tank 2 is
The pressure-reduced air is decompressed by the pressure regulating valve 3 and passed through a pipe 31 having a heating means 4 for preventing a temperature decrease due to adiabatic expansion. A passage 51 in the heat conductor 1 formed in a spiral shape in the
Is passed from above to below and supplied to the test tank 5. The pressure of the air A2 is reduced to P2 in the space 50 sealed by the lid of the test tank 5, the temperature is T2 (T1 = T2) at room temperature, the saturation tank 2 and the pressures P1 and P2 of the test tank 5 are the pressure gauge 61. , 62.

The temperature T0 of the humidifying tank 9 is measured by the thermometer 71.
The temperature T2 of the saturation tank 2 or the test tank 5 (=
T1) is detected by the temperature sensor 72 provided in the high thermal conductor 1, and both temperatures T0 and T2 are input to the control means 7.
The control means 7 uses the heater 70 at the operating end 8 so that the temperature T0 of the humidifying tank 1 detected by the temperature sensor 71 becomes slightly higher than the room temperature T2 detected by the temperature sensor 72 (T0> T2).
The power supply E supplied to Therefore, a hygrometer or the like is inserted into the space 50 of the test tank 5 to calibrate the hygrometer. or,
Excess water W generated by being slightly cooled in the saturation tank 2 and the like does not cause inconveniences such as flowing down and dropping into the humidifying tank 9 arranged in series and being stagnant on the way, and circulation by a pump or the like is prevented. Since it is unnecessary, a large amount of humidified saturated air can be generated by providing the humidifying tank 9, which is suitable for long-term operation.

That is, generally, the relative humidity U is given by the following equation.

U = (P2 / P1) · (e1 / e2) × 100 (1) where P1 is the pressure of the saturation tank 2, P2 is the pressure of the test tank 5,
e1 is the saturated water vapor pressure at the temperature T1 of the saturation tank 2, e2
Is the saturated water vapor pressure at the temperature T2 of the test tank 5.

In FIG. 1, since the temperature T1 and the temperature T2 are isothermal at room temperature in the two-pressure method, e1 = e2 and the pressures P1 and P2.
2, the relative humidity of 100% RH or less is obtained from the following equation.

U = (P2 / P1) × 100 (2) The humidifying tank 9 may have any structure, and if it is below the saturation tank 2, it is not directly below but at any angle such as diagonally. Even if it is provided at the position, the same effect can be obtained.

[0017]

As described above, in the humidity generator in which the test tank and the saturated tank are integrated, the humidifying tank for generating the humidified air is provided below the saturated tank for supplying the saturated air to the test tank. The humidity generator is provided with. For this reason,
It is small, compact and has a simple structure, does not require a large-sized constant temperature water tank, can generate extremely accurate humidity, and is suitable for calibration of hygrometers. Further, since the humidifying tank is provided vertically and in series below the saturation tank, excess water generated by cooling in the saturation tank flows down to the humidifying tank arranged in series below and falls on the way. It does not cause inconvenience such as stagnation, and does not require circulation by a pump. Further, by providing a humidifying tank, a large amount of humidified saturated air can be generated, which is suitable for long-term operation. As a whole, a large device such as a constant temperature water tank is not required, and a hygrometer calibration device can be made small and compact, and can be used for devices other than the two-pressure method.

[Brief description of drawings]

FIG. 1 is a configuration explanatory view showing one embodiment of the present invention.

[Explanation of symbols]

 1 High Thermal Conductor 2 Saturation Tank 3 Pressure Control Valve 4 Heating Means 5 Test Tank 61, 62 Pressure Gauge 7 Control Means 70 Heater 8 Operating End 9 Humidification Tank

Claims (3)

[Claims] 1. A humidity generator in which a test tank and a saturated tank are integrated, wherein a humidifying tank for generating humidified air is provided below the saturated tank for supplying saturated air to the test tank. Humidity generator. 2. The humidity generator according to claim 1, wherein the humidifying tank is provided vertically to the saturation tank. 3. The humidity generator according to claim 1, further comprising control means for controlling the temperature of the humidifying tank to be higher than the temperature of the test tank or the saturation tank.