Humidity measuring device

Abstract

To provide a more excellent humidity measuring device.SOLUTION: A humidity measuring device includes: a temperature and humidity measuring portion 26 including a thermosensor measuring temperature and a moisture sensitive element measuring humidity; a housing 102 including a housing portion 112 housing the temperature and humidity measuring portion; a display portion 14 including an indicator and fixed to the housing; and joint piping 122 connected to the middle of a pipe in which gas flows and enabling the gas to flow between pipes. The joint piping includes an orifice 130, a filter 128 is attached to the joint piping, and the housing 102 includes first piping 118 and second piping 120 connecting the joint piping and the housing portion and enabling the gas to flow between the joint piping and the housing portion.SELECTED DRAWING: Figure 22

Description

Technical Field

[0001] The present invention relates to a humidity measuring device for measuring the humidity of a gas.

Background Art

[0002] The following Patent Document 1 discloses a humidity measuring device. The humidity measuring device measures the humidity of the intake air flowing through the main air passage. An insertion hole is provided in the main air passage wall of the main air passage. The humidity measuring device is inserted into the insertion hole.

Prior Art Document

Patent Document

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Recently, a better humidity measuring device has been eagerly awaited.

Means for Solving the Problems

[0005] An aspect of the present invention is a humidity measuring device for measuring the humidity of a gas, the humidity measuring device including a measuring unit having a temperature sensing element for measuring temperature and a humidity sensing element for measuring humidity, a housing having a housing portion for housing the measuring unit, a display portion having a display and fixed to the housing, and a joint pipe connected in the middle of a pipe through which the gas flows and allowing the gas to flow between the pipes, the joint pipe having an orifice, a filter being attached to the joint pipe, and the housing having a first pipe and a second pipe connecting the joint pipe and the housing portion and allowing the gas to flow between the joint pipe and the housing portion.

Effects of the Invention

[0006] According to the present invention, a better humidity measuring device can be provided. [Brief explanation of the drawing]

[0007] [Figure 1] Figure 1 shows a humidity measuring device. [Figure 2] Figure 2 is a perspective view of the enclosure. [Figure 3] Figure 3 shows an example of the installation of a humidity measuring device. [Figure 4] Figure 4 shows an example of the installation of a humidity measuring device. [Figure 5] Figure 5 is a control block diagram of the humidity measuring device. [Figure 6] Figure 6 shows an example of the display on the indicator. [Figure 7] Figures 7A and 7B show examples of displays on the indicator. [Figure 8] Figures 8A and 8B show examples of displays on the indicator. [Figure 9] Figures 9A and 9B show the simulation results. [Figure 10] Figures 10A and 10B show the experimental environment in which the inventors conducted their experiments. [Figure 11] Figures 11A and 11B show the simulation results. [Figure 12] Figures 12A and 12B show the simulation results. [Figure 13] Figures 13A and 13B are graphs showing the experimental results. [Figure 14] Figure 14 shows a humidity measuring device. [Figure 15] Figure 15 is a control block diagram of the humidity measuring device. [Figure 16] Figure 16 shows a humidity measuring device. [Figure 17] Figure 17 is a control block diagram of the humidity measuring device. [Figure 18] Figure 18 is a control block diagram of the humidity measuring device. [Figure 19] Figure 19 is a control block diagram of the humidity measuring device. [Figure 20] Figure 20 is a control block diagram of the humidity measurement device. [Figure 21] Figure 21 is a flowchart showing the flow of the correction process. [Figure 22] Figure 22 is a diagram showing the humidity measurement device. [Figure 23] Figure 23 is a diagram showing the humidity measurement device. [Figure 24] Figure 24 is a diagram showing a state where a pipe is connected to the humidity measurement device. [Figure 25] Figure 25 shows the simulation results. [Figure 26] Figure 26 shows the simulation results. [Figure 27] Figure 27 shows the simulation results. [Figure 28] Figure 28 is a diagram showing the humidity measurement device. [Figure 29] Figure 29 is a diagram showing the humidity measurement device.

Embodiments for Carrying Out the Invention

[0008] 〔First Embodiment〕 Figure 1 shows the humidity measurement device 10. The humidity measurement device 10 has a housing 12 and a display unit 14. Figure 1 shows the housing 12 in a cross-sectional view. Figure 1 shows the display unit 14 in a schematic diagram. The humidity measurement device 10 measures the relative humidity of the gas and the temperature of the gas. Hereinafter, the relative humidity is described as humidity.

[0009] The housing 12 has a main body 16 and a connecting part 18. The main body 16 has a housing 20 inside the main body 16. This housing 20 is a space formed inside the main body 16. The main body 16 has a supply pipe 22 inside the main body 16. The main body 16 has an exhaust pipe 24 inside the main body 16. The supply pipe 22 is connected to the housing 20. The exhaust pipe 24 is connected to the housing 20. As shown in Figure 1, the opening of the exhaust pipe 24 in the housing 20 is positioned radially offset from the opening of the supply pipe 22 in the housing 20. Gas is supplied from the supply pipe 22 to the housing 20. The gas supplied to the housing 20 is discharged into the atmosphere from the exhaust pipe 24.

[0010] The humidity measuring device 10 has an electronic circuit board 25. The electronic circuit board 25 is positioned between the main body 16 and the display unit 14. A temperature and humidity measuring unit 26 is mounted on the electronic circuit board 25. The temperature and humidity measuring unit 26 is housed in a housing unit 20. The temperature and humidity measuring unit 26 is an electronic component in which a temperature sensing element and a humidity sensing element are mounted on a single integrated circuit. The temperature sensing element measures the temperature of the gas inside the housing unit 20. The humidity sensing element measures the humidity of the gas inside the housing unit 20. The temperature and humidity measuring unit 26 corresponds to the measuring unit of the present invention. The temperature and humidity measuring unit 26 outputs the measured temperature and humidity of the gas to the display unit 14.

[0011] The connecting part 18 is attached to the main body 16. The connecting part 18 has a connecting pipe 28 inside. Gas can flow between the connecting pipe 28 and the supply pipe 22 of the main body 16.

[0012] The connecting pipe 28 has an orifice 30. A filter 32 is attached to the connecting pipe 28. The filter 32 is made of metal. The orifice 30 is positioned in the connecting pipe 28 closer to the main body 16 than the position where the filter 32 is attached. That is, the orifice 30 is positioned closer to the housing 20 than the position where the filter 32 is attached. The cross-sectional area of ​​the smallest diameter portion of the orifice 30 is smaller than the cross-sectional area of ​​the exhaust pipe 24. Therefore, the flow resistance of the path for discharging gas from the housing 20 (hereinafter referred to as the discharge path) is smaller than the flow resistance of the path for supplying gas to the housing 20 (hereinafter referred to as the supply path). As a result, the pressure of the gas inside the housing 20 is atmospheric pressure. The temperature and humidity measuring unit 26 housed in the housing 20 measures the temperature of the gas under atmospheric pressure. The temperature and humidity measuring unit 26 housed in the housing 20 measures the humidity of the gas under atmospheric pressure.

[0013] Figure 2 is a perspective view of the housing 12. The connection part 18 is fixed to the main body 16 by a connection pin 34. The user can remove the connection pin 34. With the connection pin 34 removed from both the main body 16 and the connection part 18, the user can remove the connection part 18 from the main body 16. With the filter 32 attached to the connection part 18, the connection part 18 is removed from the main body 16. This allows the user to easily replace the filter 32 of the humidity measuring device 10.

[0014] Figure 3 shows an example of the installation of the humidity measuring device 10. The humidity measuring device 10 is installed in the piping 36. Compressed gas flows through the inside of the piping 36. Compressed gas is a gas whose pressure is greater than atmospheric pressure. Hereafter, compressed gas may be simply referred to as gas.

[0015] The temperature, humidity, and dew point temperature of a gas vary with its pressure. For compressed gases where the pressure is greater than atmospheric pressure, these may be described as the temperature under pressure, the humidity under pressure, and the dew point temperature under pressure. For gases where the pressure is atmospheric pressure, these may be described as the temperature under atmospheric pressure, the humidity under atmospheric pressure, and the dew point temperature under atmospheric pressure.

[0016] The humidity measuring device 10 measures the humidity and temperature of the gas flowing inside the pipe 36. The connection part 18 of the humidity measuring device 10 is inserted into an insertion hole (not shown) provided in the pipe 36. As a result, a portion of the gas flowing inside the pipe 36 is supplied to the housing part 20 by passing through the connection pipe 28 of the connection part 18 and the supply pipe 22 of the main body part 16. The gas flowing inside the pipe 36 is the gas that has been dehumidified by the dehumidifier 38 described below.

[0017] Figure 4 shows an example of the installation of the humidity measuring device 10. The humidity measuring device 10 may also be installed on the dehumidifier 38. The dehumidifier 38 removes moisture from the gas passing through it. The humidity measuring device 10 measures the humidity and temperature of the compressed gas discharged from the dehumidifier 38.

[0018] As shown in Figure 1, the display unit 14 is fixed to the main body 16 of the housing 12. Figure 5 is a control block diagram of the humidity measuring device 10. The configuration of the display unit 14 will be explained using the control block diagram in Figure 5.

[0019] The display unit 14 includes a dew point temperature calculation unit 40, a set value storage unit 42, a first output unit 44, a second output unit 48, a display control unit 52, and a display 54.

[0020] The dew point temperature calculation unit 40 calculates the dew point temperature of the gas at atmospheric pressure based on the temperature and humidity measurement unit 26's measurement of the gas's temperature and humidity. The dew point temperature calculation unit 40 outputs the calculated dew point temperature to the first output unit 44, the second output unit 48, and the display control unit 52.

[0021] Hereinafter, "the temperature of the gas measured by the temperature / humidity measuring unit 26" may be referred to as "measured temperature." "The humidity of the gas measured by the temperature / humidity measuring unit 26" may be referred to as "measured humidity." "The dew point temperature of the gas calculated by the dew point temperature calculation unit 40" may be referred to as "calculated dew point temperature."

[0022] The setting value storage unit 42 stores the set temperature, set humidity, and set dew point temperature. The set temperature, set humidity, and set dew point temperature are input to the first output unit 44, which will be described later. The set temperature, set humidity, and set dew point temperature may be values ​​set by the user of the humidity measuring device 10. The set temperature, set humidity, and set dew point temperature may also be values ​​set by the manufacturer of the humidity measuring device 10 at the time of shipment.

[0023] The first output unit 44 compares the set temperature with the measured temperature. The first output unit 44 outputs the comparison result (hereinafter sometimes referred to as the temperature comparison result) to the external device 46. The temperature comparison result may be information that numerically indicates the difference between the set temperature and the measured temperature. The temperature comparison result may also be information that indicates whether the measured temperature is higher or lower than the set temperature.

[0024] The first output unit 44 compares the set humidity with the measured humidity. The first output unit 44 outputs the comparison result (hereinafter sometimes referred to as the humidity comparison result) to the external device 46. The humidity comparison result may be information that numerically shows the difference between the set humidity and the measured humidity. The humidity comparison result may also be information that indicates whether the measured humidity is higher or lower than the set humidity.

[0025] The first output unit 44 compares the set dew point temperature with the calculated dew point temperature. The first output unit 44 outputs the comparison result (hereinafter sometimes referred to as the dew point temperature comparison result) to the external device 46. The dew point temperature comparison result may be information that numerically shows the difference between the set dew point temperature and the calculated dew point temperature. The dew point temperature comparison result may also be information that indicates whether the calculated dew point temperature is higher or lower than the set dew point temperature.

[0026] The second output unit 48 outputs the measured temperature to the external device 50. The second output unit 48 outputs the measured humidity to the external device 50. The second output unit 48 outputs the calculated dew point temperature to the external device 50. The external device 50 may be the same device as the external device 46. The external device 50 may be a different device from the external device 46.

[0027] The display control unit 52 controls the display unit 54 to display information regarding the measured temperature. The display control unit 52 controls the display unit 54 to display information regarding the measured humidity. The display control unit 52 controls the display unit 54 to display information regarding the calculated dew point temperature. The display control unit 52 may control the display unit 54 to display at least one of the following information on the display unit 54: information regarding the measured temperature, information regarding the measured humidity, and information regarding the calculated dew point temperature. The units for the measured temperature, calculated dew point temperature, set temperature, and set dew point temperature are all "°C".

[0028] Figure 6 shows an example of the display of the display unit 54. The display unit 54 has a humidity display area 56. The humidity display area 56 displays the measured humidity numerically. The display unit 54 has a dew point temperature display area 58. The dew point temperature display area 58 displays the calculated dew point temperature numerically. The display unit 54 has a temperature display area 60. The temperature display area 60 displays the measured temperature numerically.

[0029] Figures 7A and 7B show examples of the display of the display unit 54. The display examples of the display unit 54 in Figures 7A and 7B are different from the display example of the display unit 54 in Figure 6. The display unit 54 has a humidity display area 62. The humidity display area 62 displays the measured humidity numerically. The display unit 54 has a dew point temperature display area 64. The two slashes " / / " shown near the center of the dew point temperature display area 64 in Figures 7A and 7B indicate the position where the calculated dew point temperature is 0°C. When the calculated dew point temperature is negative, a bar (g-segment) "-" is displayed only to the right of the slash " / / ", as shown in Figure 7A. When the calculated dew point temperature is positive, the bar (g-segment) "-" extends to the left of the slash " / / ", as shown in Figure 7B. In the dew point temperature display area 64, the further the bar (g segment) "-" extends to the left, the higher the calculated dew point temperature indicated by the display unit 54.

[0030] Figures 8A and 8B show examples of the display of the display unit 54. The display examples of the display unit 54 in Figures 8A and 8B are different from the display examples of the display unit 54 in Figures 6, 7A, and 7B. The display unit 54 has a humidity display area 66. The humidity display area 66 displays the measured humidity numerically. The display unit 54 has a temperature display area 68. The temperature display area 68 displays the measured temperature numerically. The display unit 54 indicates the calculated dew point temperature by the color of the numbers in the humidity display area 66. If the calculated dew point temperature is negative, the display unit 54 displays the numbers in the humidity display area 66 in blue. If the calculated dew point temperature is positive, the display unit 54 displays the numbers in the humidity display area 66 in red. The above examples of the colors of the numbers in the humidity display area 66 are just examples, and the calculated dew point temperature information may be indicated by a different color.

[0031] Each component of the display unit 14, excluding the display unit 54, is implemented by a microcontroller (not shown). An arithmetic processing unit (not shown) mounted on the microcontroller executes a program stored in a memory (not shown) mounted on the microcontroller, thereby realizing the functions of the dew point temperature calculation unit 40, the first output unit 44, the second output unit 48, and the display control unit 52. The setting value storage unit 42 is implemented by reserving a storage area in a part of the memory to store each setting value.

[0032] Furthermore, each component of the display unit 14, excluding the display unit 54, may be composed of integrated circuits such as FPGAs (Field Programmable Gate Arrays) and ASICs (application-specific integrated circuits), which are not shown in the diagram.

[0033] [Regarding the connection between the supply piping and the housing, and the connection between the exhaust piping and the housing] In this embodiment, as shown in Figure 1, the opening of the exhaust pipe 24 in the housing section 20 is positioned offset from the opening of the supply pipe 22 in the housing section 20. As a result, the gas flowing into the housing section 20 from the supply pipe 22 is diffused within the housing section 20 before being discharged from the exhaust pipe 24.

[0034] The inventors performed a computer simulation to determine the humidity distribution of the gas inside the containment section 20. Figures 9A and 9B show the simulation results. Figure 9A shows the simulation results for Comparative Example 1. In Comparative Example 1, the direction in which gas flows from the supply pipe 22 into the containment section 20 and the direction in which gas flows out from the containment section 20 into the exhaust pipe 24 are aligned on a straight line. Figure 9B shows the simulation results for Comparative Example 2. In Comparative Example 2, the opening of the exhaust pipe 24 in the containment section 20 is positioned offset radially from the opening of the supply pipe 22 in the containment section 20. As a result, in Comparative Example 2, the direction in which gas flows from the supply pipe 22 into the containment section 20 and the direction in which gas flows out from the containment section 20 into the exhaust pipe 24 are aligned on different straight lines.

[0035] In the simulations for Comparative Example 1 and Comparative Example 2, the diameter of the orifice 30 hole was set to 0.2 mm. In the simulations for Comparative Example 1 and Comparative Example 2, the humidity of the gas flowing into the containment section 20 was set to 50%. In the simulations for Comparative Example 1 and Comparative Example 2, the flow rate of the gas flowing into the containment section 20 was set to 1 L / min.

[0036] In Comparative Example 1, the gas flowing into the containment section 20 from the supply pipe 22 is discharged to the exhaust pipe 24 without being diffused within the containment section 20. Therefore, in the simulation for Comparative Example 1, as shown in Figure 9A, the distribution of gas humidity in the containment section 20 is not uniform. On the other hand, in Comparative Example 2, the gas flowing into the containment section 20 from the supply pipe 22 collides with the side surface of the containment section 20, is diffused within the containment section 20, and is then discharged to the exhaust pipe 24. Therefore, in the simulation for Comparative Example 2, as shown in Figure 9B, the distribution of gas humidity in the containment section 20 is approximately uniform.

[0037] These simulation results showed that in Comparative Example 2, the gas flowing into the containment section 20 diffused over a wider area compared to Comparative Example 1.

[0038] The inventors conducted experiments on the measurement accuracy of the gas humidity in the temperature and humidity measuring unit 26. Figures 10A and 10B show the experimental environment in which the inventors conducted their experiments. Figure 10A shows the experimental environment in Comparative Example 3. In Comparative Example 3, the direction in which gas flows from the supply pipe 22 into the containment unit 20 and the direction in which gas flows out from the containment unit 20 into the exhaust pipe 24 are aligned in a straight line. Figure 10B shows the experimental environment in Comparative Example 4. In Comparative Example 4, the opening of the exhaust pipe 24 in the containment unit 20 is positioned offset radially from the opening of the supply pipe 22 in the containment unit 20. As a result, in Comparative Example 4, the direction in which gas flows from the supply pipe 22 into the containment unit 20 and the direction in which gas flows out from the containment unit 20 into the exhaust pipe 24 are aligned in different straight lines. In these experiments, dry gas (humidity 8.0%) was introduced into the containment unit 20, which was in a normal humidity state (humidity 25.0%).

[0039] In the experimental environment of Comparative Example 3 shown in Figure 10A, the humidity measured by the temperature / humidity measuring unit 26 was 10.3%. The error between the humidity measured by the temperature / humidity measuring unit 26 (10.3%) and the humidity of the gas introduced into the containment unit 20 (8.0%) was +2.3%. In the experimental environment of Comparative Example 4 shown in Figure 10B, the humidity measured by the temperature / humidity measuring unit 26 was 8.3%. The error between the humidity measured by the temperature / humidity measuring unit 26 (8.3%) and the humidity of the gas introduced into the containment unit 20 (8.0%) was +0.3%.

[0040] These experimental results demonstrate that the accuracy of measuring the humidity of the gas by the temperature and humidity measuring unit 26 is improved in Comparative Example 4 compared to Comparative Example 3.

[0041] [About the orifice] In the humidity measuring device 10 of this embodiment, since the connecting pipe 28 has an orifice 30, the flow resistance of the gas discharge path of the containment section 20 is smaller than the flow resistance of the gas supply path of the containment section 20. As a result, the pressure of the gas in the containment section 20 becomes atmospheric pressure. Instead of the orifice 30, a structure in which the connecting pipe 28 has a pressure reducing valve can be considered. The pressure reducing valve can adjust the pressure of the gas supplied to the containment section 20 to atmospheric pressure by releasing a portion of the gas passing through the connecting pipe 28 into the atmosphere. The structure of the orifice 30 is simpler than the structure of the pressure reducing valve. In the humidity measuring device 10 of this embodiment, since the connecting pipe 28 has an orifice 30 instead of a pressure reducing valve, the structure of the humidity measuring device 10 can be simplified.

[0042] The filter 32 attached to the connecting pipe 28 creates resistance to the gas passing through it. Therefore, it is conceivable that the filter 32 increases the flow resistance of the supply path. Typically, the filter 32 is designed to remove foreign matter from the gas passing through it while minimizing resistance to the gas passing through it. In order to generate flow resistance in the filter 32 equivalent to that of the orifice 30, the filter 32 attached to the connecting pipe 28 needs to be considerably longer than the axial length of the hole in the orifice 30. In the humidity measuring device 10 of this embodiment, the orifice 30 increases the flow resistance of the supply path, allowing the humidity measuring device 10 to be made smaller.

[0043] When the orifice 30 increases the flow resistance of the supply path compared to when the filter 32 increases the flow resistance of the supply path, the flow velocity of the gas flowing into the containment section 20 increases. The higher the flow velocity of the gas flowing into the containment section 20, the wider the area the gas diffuses when it collides with the side surface of the containment section 20. The higher the flow velocity of the gas flowing into the containment section 20, the shorter the time it takes for the gas to collide with the side surface of the containment section 20 after it has entered the containment section 20, and the faster the gas diffuses.

[0044] Therefore, compared to the case where the filter 32 increases the flow resistance of the supply path, when the orifice 30 increases the flow resistance of the supply path, the gas flowing into the containment section 20 diffuses more widely and faster within the containment section 20. As a result, compared to the case where the filter 32 increases the flow resistance of the supply path, when the orifice 30 increases the flow resistance of the supply path, the response speed of the temperature and humidity measurement unit 26 to changes in the temperature, humidity, etc., of the gas being measured is improved.

[0045] The inventors performed a computer simulation to determine the flow velocity of the gas flowing into the containment section 20. Figures 11A and 11B show the simulation results. Figure 11A shows the simulation results when the filter 32 increases the flow resistance of the supply path. Figure 11B shows the simulation results when the orifice 30 increases the flow resistance of the supply path.

[0046] In these simulations, the inner diameter of the supply pipe 22 was set to 3 mm. In these simulations, the inner diameter of the pipe in the section where the filter 32 is installed was set to 1 mm, and the outer diameter of the filter 32 was also set to 1 mm. In these simulations, the length of the filter 32 was set to 4 mm. In these simulations, the inner diameter of the hole in the orifice 30 was set to 0.2 mm. In these simulations, the axial length of the hole in the orifice 30 was set to 0.2 mm. In these simulations, the humidity of the gas flowing into the containment section 20 was set to 50%. In these simulations, the flow rate of the gas flowing into the containment section 20 was set to 1 L / min.

[0047] When filter 32 increases the flow resistance of the supply path, as shown in Figure 11A, the flow velocity of the gas passing through filter 32 is high, but the flow velocity of the gas after passing through filter 32 decreases. The reason why the flow velocity of the gas after passing through filter 32 decreases despite the high flow velocity of the gas passing through filter 32 is as follows.

[0048] At the inlet where the gas flows into the filter 32, the gas velocity is high because the gas flows from the supply pipe 22 (inner diameter 3 mm) into the filter 32 (outer diameter 1 mm). Inside the filter 32, the higher the gas velocity, the greater the flow resistance of the filter 32 to the gas. Therefore, as the gas passes through the filter 32, it diffuses (spreads) from areas of high flow resistance to areas of low flow resistance inside the filter 32. As a result, at the outlet where the gas flows out of the filter 32, the gas velocity remains approximately constant, regardless of the gas velocity at the inlet. Due to the flow resistance of the filter 32 to the gas, the pressure of the gas after passing through the filter 32 is lower than the pressure of the gas before passing through the filter 32. However, because the gas diffuses (spreads) inside the filter 32 as it passes through, the gas velocity is suppressed to a speed that depends on the external shape of the filter 32. At the aforementioned outlet section, gas flows from the filter 32 (outer diameter 1 mm) into the supply pipe 22 (inner diameter 3 mm), causing the gas flow velocity to decrease further.

[0049] On the other hand, if the orifice 30 increases the flow resistance of the supply path, the gas velocity after passing through the orifice 30 remains high, as shown in Figure 11B. The reason why the gas velocity after passing through the orifice 30 is maintained is as follows.

[0050] At the inlet where the gas flows into the orifice 30, the gas velocity increases as the gas flows from the supply pipe 22 (inner diameter 3 mm) into the hole (inner diameter 0.2 mm) of the orifice 30. Due to the flow resistance of the orifice 30 to the gas, the pressure of the gas after passing through the orifice 30 decreases compared to the pressure of the gas before passing through the orifice 30. The axial length of the hole in the orifice 30 is 0.2 mm, and the gas velocity increases significantly as the gas passes through the hole in the orifice 30. On the other hand, at the outlet where the gas flows out of the orifice 30, the gas velocity decreases as the gas flows from the hole (inner diameter 0.2 mm) of the orifice 30 into the supply pipe 22 (inner diameter 3 mm). However, since the gas velocity increases sufficiently as the gas passes through the orifice 30, a high gas velocity can be maintained even within the supply pipe 22.

[0051] These simulation results showed that when the orifice 30 increases the flow resistance of the supply path, the flow velocity of the gas flowing into the containment section 20 is higher compared to when the filter 32 increases the flow resistance of the supply path.

[0052] The inventors performed a computer simulation to determine the humidity distribution of the gas within the containment section 20. Figures 12A and 12B show the simulation results. Figure 12A shows the simulation results when the filter 32 increases the flow resistance of the supply path. Figure 12B shows the simulation results when the orifice 30 increases the flow resistance of the supply path.

[0053] In these simulations, the outer diameter of filter 32 was set to 1 mm. In these simulations, the length of filter 32 was set to 4 mm. In these simulations, the diameter of the hole in orifice 30 was set to 0.2 mm. In these simulations, the length of the hole in orifice 30 was set to 0.2 mm. In these simulations, the humidity of the gas flowing into the containment section 20 was set to 50%. In these simulations, the flow rate of the gas flowing into the containment section 20 was set to 1 L / min.

[0054] When the filter 32 increases the flow resistance of the supply path, the distribution of gas humidity in the containment section 20 is not uniform, as shown in Figure 12A. On the other hand, when the orifice 30 increases the flow resistance of the supply path, the distribution of gas humidity in the containment section 20 becomes approximately uniform, as shown in Figure 12B.

[0055] As the simulation results in Figures 11A and 11B show, the flow velocity of the gas flowing into the containment section 20 is higher when the orifice 30 increases the flow resistance of the supply path compared to when the filter 32 increases the flow resistance of the supply path. The higher the flow velocity of the gas flowing into the containment section 20, the wider the gas diffuses when it collides with the sides of the containment section 20.

[0056] The simulation results shown in Figures 12A and 12B indicate that when the orifice 30 increases the flow resistance of the supply path, the gas flowing into the containment section 20 diffuses more within the containment section 20 compared to when the filter 32 increases the flow resistance of the supply path.

[0057] The inventors conducted an experiment on the response speed of the temperature / humidity measuring unit 26 to changes in the humidity of the gas being measured. In the experiment, the inventors measured the humidity of the gas after it passed through the orifice 30 and the humidity of the gas after it passed through the filter 32 using the temperature / humidity measuring unit 26. In the experiment, the diameter of the hole in the orifice 30 was set to 0.25 mm. In the experiment, the outer diameter of the filter 32 was set to 1.0 mm.

[0058] In the first experiment (hereinafter referred to as Experiment 1), the containment unit 20 was filled with gas at 5% humidity before the start of the experiment. For 5 seconds after the start of the experiment, gas at 5% humidity was supplied to the containment unit 20. Five seconds after the start of the experiment, the supply of gas at 45% humidity to the containment unit 20 was started. In the second experiment (hereinafter referred to as Experiment 2), the containment unit 20 was filled with gas at 45% humidity before the start of the experiment. For 5 seconds after the start of the experiment, gas at 45% humidity was supplied to the containment unit 20. Five seconds after the start of the experiment, the supply of gas at 5% humidity to the containment unit 20 was started.

[0059] Figures 13A and 13B show the experimental results. Figure 13A shows the results of Experiment 1, in which the humidity of the gas supplied to the containment section 20 was changed from 5% to 45%. Figure 13B shows the results of Experiment 2, in which the humidity of the gas supplied to the containment section 20 was changed from 45% to 5%. In Experiment 1, the measured humidity of the gas after passing through the orifice 30 increased faster than the measured humidity of the gas after passing through the filter 32. In Experiment 2, the measured humidity of the gas after passing through the orifice 30 decreased faster than the measured humidity of the gas after passing through the filter 32.

[0060] These experimental results show that when the orifice 30 increases the flow resistance of the supply path, compared to when the filter 32 increases the flow resistance of the supply path, the response speed of the temperature and humidity measuring unit 26 to changes in the humidity of the gas being measured is improved.

[0061] [Effects and Effects] In this embodiment, the humidity measuring device 10 has a display unit 14 fixed to the housing 12. The display unit 14 has a display 54. The display 54 displays the humidity of the gas, the temperature of the gas, and the dew point temperature of the gas. This allows the user to check the humidity of the gas, the temperature of the gas, and the dew point temperature of the gas at the location where the humidity measuring device 10 is installed.

[0062] In the humidity measuring device 10 of this embodiment, the first output unit 44 outputs the comparison result between the set humidity and the humidity of the gas measured by the temperature and humidity measuring unit 26 (measured humidity) to the external device 46. As a result, the humidity measuring device 10 of this embodiment can output the comparison result between the set humidity and the measured humidity to the external device 46.

[0063] In the humidity measuring device 10 of this embodiment, the first output unit 44 outputs the comparison result between the set dew point temperature and the gas dew point temperature (calculated dew point temperature) calculated by the dew point temperature calculation unit 40 to the external device 46. As a result, the humidity measuring device 10 of this embodiment can output the comparison result between the set dew point temperature and the calculated dew point temperature to the external device 46.

[0064] In the humidity measuring device 10 of this embodiment, the temperature and humidity measuring unit 26 measures the humidity of the gas (measured humidity), and the second output unit 48 outputs this measured humidity to the external device 50. This allows the humidity measuring device 10 of this embodiment to output the measured humidity to the external device 50.

[0065] In the humidity measuring device 10 of this embodiment, the second output unit 48 outputs the dew point temperature of the gas (calculated dew point temperature) calculated by the dew point temperature calculation unit 40 to the external device 50. As a result, the humidity measuring device 10 of this embodiment can output the calculated dew point temperature to the external device 50.

[0066] In the humidity measuring device 10 of this embodiment, the direction in which gas flows from the supply pipe 22 to the containment section 20 and the direction in which gas flows out from the containment section 20 to the exhaust pipe 24 are located on opposite straight lines. As a result, the temperature and humidity measuring unit 26 of this embodiment can improve the accuracy of measuring the humidity of the gas.

[0067] In the humidity measuring device 10 of this embodiment, the connecting pipe 28 has an orifice 30. The cross-sectional area of ​​the hole in the orifice 30 is smaller than the cross-sectional area of ​​the exhaust pipe 24. As a result, the flow resistance of the gas supply path is greater than the flow resistance of the gas discharge path. Therefore, it is possible to set the pressure of the gas in the containment section 20 to atmospheric pressure. The dew point temperature calculation unit 40 can calculate the dew point temperature of the gas at atmospheric pressure based on the gas temperature and humidity measured by the temperature and humidity measuring unit 26.

[0068] In this embodiment, the humidity measuring device 10 has a filter 32 attached to the connecting pipe 28. Furthermore, the orifice 30 is positioned closer to the housing section 20 than the filter 32. This prevents foreign matter from clogging the hole in the orifice 30 of the connecting pipe 28.

[0069] In this embodiment, the humidity measuring device 10 has a metal filter 32. This suppresses moisture absorption from the gas by the filter 32. Therefore, the humidity measuring device 10 of this embodiment can improve the accuracy of measuring the humidity of the gas.

[0070] In this embodiment, the humidity measuring device 10 allows the user to remove the connection part 18 from the main body 16 while the filter 32 is attached to the connection part 18. The user can easily replace the filter 32 of the humidity measuring device 10.

[0071] [Second Embodiment] Figure 14 shows the humidity measuring device 10. Figure 14 shows a cross-sectional view of the housing 12. Figure 14 shows a schematic diagram of the display unit 14.

[0072] In the humidity measuring device 10 of the first embodiment, the connecting pipe 28 formed inside the connecting part 18 has an orifice 30 (Figure 1). In contrast, in the humidity measuring device 10 of this embodiment, the connecting pipe 28 formed inside the connecting part 18 does not have an orifice (Figure 14). In the humidity measuring device 10 of this embodiment, the exhaust pipe 24 formed inside the main body part 16 of the housing 12 has an orifice 70. The cross-sectional area of ​​the smallest diameter portion of the hole in the orifice 70 is smaller than the cross-sectional area of ​​the supply pipe 22. The cross-sectional area of ​​the smallest diameter portion of the hole in the orifice 70 is smaller than the cross-sectional area of ​​the connecting pipe 28. The other configurations of the humidity measuring device 10 of this embodiment are the same as those of the humidity measuring device 10 of the first embodiment.

[0073] Since the connecting pipe 28 does not have an orifice and the exhaust pipe 24 has an orifice 70, the pressure of the gas inside the containment section 20 is approximately the same as the pressure of the compressed gas inside the pipe 36 or the pressure of the compressed gas discharged by the dehumidifier 38. The temperature and humidity measuring section 26 measures the temperature under pressure of the gas. The temperature and humidity measuring section 26 measures the humidity under pressure of the gas. The dew point temperature calculation section 40 of the display section 14 calculates the dew point temperature under pressure of the gas based on the temperature under pressure of the gas measured by the temperature and humidity measuring section 26 and the humidity under pressure of the gas measured by the temperature and humidity measuring section 26.

[0074] [Effects and Effects] In the humidity measuring device 10 of this embodiment, the exhaust pipe 24 has an orifice 70. The cross-sectional area of ​​the hole in the orifice 70 is smaller than the cross-sectional area of ​​the supply pipe 22. The cross-sectional area of ​​the hole in the orifice 70 is smaller than the cross-sectional area of ​​the connecting pipe 28. Since the connecting pipe 28 does not have an orifice and the exhaust pipe 24 has an orifice 70, the pressure of the gas in the containment section 20 is approximately the same as the pressure of the compressed gas in the pipe 36 or the pressure of the compressed gas discharged by the dehumidifier 38. The temperature and humidity measuring section 26 can measure the temperature of the gas under pressure. The temperature and humidity measuring section 26 can measure the humidity of the gas under pressure. The dew point temperature calculation section 40 can calculate the dew point temperature of the gas under pressure based on the temperature of the gas under pressure measured by the temperature and humidity measuring section 26 and the humidity of the gas under pressure measured by the temperature and humidity measuring section 26.

[0075] [Third Embodiment] Figure 15 is a control block diagram of the humidity measuring device 10. The configuration of the display unit 14 will be explained using the control block diagram of Figure 15.

[0076] The display unit 14 of the humidity measuring device 10 in this embodiment includes a dew point temperature calculation unit 40, a first output unit 44, a display control unit 52, a display 54, and a communication unit 72. The dew point temperature calculation unit 40, the display control unit 52, and the display 54 are the same as those of the display unit 14 of the humidity measuring device 10 in the first embodiment.

[0077] The communication unit 72 communicates with the external device 46. The communication unit 72 receives the set temperature, set humidity, and set dew point temperature from the external device 46. The communication unit 72 outputs the set temperature, set humidity, and set dew point temperature received by the communication unit 72 to the first output unit 44. The set temperature, set humidity, and set dew point temperature may be values ​​set by the user of the external device 46. The set temperature, set humidity, and set dew point temperature may also be values ​​set by the manufacturer of the external device 46 at the time of shipment of the humidity measuring device 10.

[0078] The first output unit 44 outputs the comparison result between the set temperature and the measured temperature to the communication unit 72. The first output unit 44 outputs the comparison result between the set humidity and the measured humidity to the communication unit 72. The first output unit 44 outputs the comparison result between the set dew point temperature and the calculated dew point temperature to the communication unit 72.

[0079] The communication unit 72 transmits the comparison result between the set temperature and the measured temperature to the external device 46. The communication unit 72 transmits the comparison result between the set humidity and the measured humidity to the external device 46. The communication unit 72 transmits the comparison result between the set dew point temperature and the calculated dew point temperature to the external device 46.

[0080] [Effects and Effects] In the humidity measuring device 10 of this embodiment, the display unit 14 has a communication unit 72. The communication unit 72 communicates with an external device 46. The communication unit 72 can receive each setting value set on the external device 46. As a result, in the humidity measuring device 10 of this embodiment, the first output unit 44 can compare each setting value set on the external device 46 with the measured temperature, measured humidity, and calculated dew point temperature. In the humidity measuring device 10 of this embodiment, the communication unit 72 can transmit the comparison results made by the first output unit 44 to the external device 46.

[0081] [Fourth Embodiment] Figure 16 shows the humidity measuring device 10. The humidity measuring device 10 has a housing 74 and a display unit 14. Figure 16 shows a cross-sectional view of the housing 74. Figure 16 shows a schematic diagram of the display unit 14.

[0082] The housing 74 has a housing section 78 inside. The housing 74 has a supply pipe 80 inside. The housing 74 has an exhaust pipe 82 inside. The supply pipe 80 is connected to the housing section 78. The exhaust pipe 82 is connected to the housing section 78. The gas to be measured by the humidity measuring device 10 is supplied from the supply pipe 80 to the housing section 78. The gas supplied to the housing section 78 is discharged into the atmosphere from the exhaust pipe 82. The opening of the exhaust pipe 82 in the housing section 78 is positioned radially offset from the opening of the supply pipe 80 in the housing section 78.

[0083] The humidity measuring device 10 has an electronic circuit board 84. The electronic circuit board 84 is positioned between the housing 74 and the display unit 14. A temperature and humidity measuring unit 26 is mounted on the electronic circuit board 84. The temperature and humidity measuring unit 26 is housed in a housing unit 78.

[0084] The supply pipe 80 has an orifice 86. A filter 88 is attached to the supply pipe 80. The filter 88 is made of metal. The orifice 86 is positioned closer to the housing 78 than the position where the filter 88 is attached. The cross-sectional area of ​​the smallest diameter portion of the orifice 86 is smaller than the cross-sectional area of ​​the exhaust pipe 82. Therefore, the flow resistance of the path for discharging gas from the housing 78 (hereinafter referred to as the discharge path) is smaller than the flow resistance of the path for supplying gas to the housing 78 (hereinafter referred to as the supply path). As a result, the pressure of the gas inside the housing 78 is equal to atmospheric pressure. The temperature and humidity measuring unit 26 measures the temperature of the gas inside the housing 78. The temperature and humidity measuring unit 26 measures the humidity of the gas inside the housing 78. The temperature and humidity measuring unit 26 outputs the measured temperature and humidity of the gas to the display unit 14.

[0085] The housing 74 has a branch pipe 90 inside. The branch pipe 90 is connected to the supply pipe 80. The connection point of the branch pipe 90 in the supply pipe 80 is between the orifice 86 and the filter 88 of the supply pipe 80. A pressure measuring unit 76 is mounted on the electronic circuit board 84. The branch pipe 90 supplies the gas to the pressure measuring unit 76 before it passes through the orifice 86. The pressure measuring unit 76 measures the pressure of the supplied gas. When the humidity measuring device 10 is installed in the pipe 36, the pressure of the gas supplied to the pressure measuring unit 76 is approximately the same as the pressure of the compressed gas flowing through the pipe 36. When the humidity measuring device 10 is installed in the dehumidifier 38, the pressure of the gas supplied to the pressure measuring unit 76 is approximately the same as the pressure of the compressed gas discharged from the dehumidifier 38. As a result, the pressure measuring unit 76 can measure the pressure of the gas at the measurement point.

[0086] Figure 17 is a control block diagram of the humidity measuring device 10. The configuration of the display unit 14 will be explained using the control block diagram of Figure 17.

[0087] The display unit 14 of the humidity measuring device 10 in this embodiment includes a dew point temperature calculation unit 40, a display control unit 52, and a display 54. The display control unit 52 and the display 54 of the display unit 14 of the humidity measuring device 10 in this embodiment are the same as the display control unit 52 and the display 54 of the display unit 14 of the humidity measuring device 10 in the first embodiment.

[0088] The dew point temperature calculation unit 40 receives the temperature of the gas under atmospheric pressure measured by the temperature and humidity measurement unit 26. The dew point temperature calculation unit 40 receives the humidity of the gas under atmospheric pressure measured by the temperature and humidity measurement unit 26. The dew point temperature calculation unit 40 receives the pressure of the gas measured by the pressure measurement unit 76. When the humidity measuring device 10 is installed in the piping 36, the pressure measurement unit 76 measures the pressure of the compressed gas flowing through the piping 36. When the humidity measuring device 10 is installed in the dehumidifier 38, the pressure measurement unit 76 measures the pressure of the compressed gas discharged from the dehumidifier 38. The dew point temperature calculation unit 40 calculates the dew point temperature of the gas under atmospheric pressure based on the temperature of the gas under atmospheric pressure measured by the temperature and humidity measurement unit 26 and the humidity of the gas under atmospheric pressure measured by the temperature and humidity measurement unit 26. The dew point temperature calculation unit 40 corrects the dew point temperature of the gas at atmospheric pressure calculated by the dew point temperature calculation unit 40 according to the pressure of the gas measured by the pressure measuring unit 76, and calculates the dew point temperature of the gas at pressure.

[0089] [Effects and Effects] Even if the absolute humidity (amount of water contained in the gas) of a gas is the same, the dew point temperature will be higher as the pressure of the gas increases. Therefore, the higher the pressure of the gas in contact with the temperature and humidity measuring unit 26, the more likely water droplets are to adhere to the temperature and humidity measuring unit 26. If water droplets adhere to the temperature and humidity measuring unit 26, the humidity measured by the temperature and humidity measuring unit 26 may become an abnormal value.

[0090] The humidity measuring device 10 of this embodiment has a pressure measuring unit 76 that measures the pressure of the gas at the measurement position where the humidity measuring device 10 measures the humidity of the gas. The dew point temperature calculation unit 40 calculates the dew point temperature of the gas at atmospheric pressure based on the temperature of the gas at atmospheric pressure measured by the temperature and humidity measuring unit 26 and the humidity of the gas at atmospheric pressure measured by the temperature and humidity measuring unit 26. The dew point temperature calculation unit 40 corrects the dew point temperature of the gas at atmospheric pressure calculated by the dew point temperature calculation unit 40 according to the pressure of the gas measured by the pressure measuring unit 76 to calculate the dew point temperature of the gas under pressure. As a result, the temperature and humidity measuring unit 26 does not come into contact with the high-pressure gas, and the adhesion of water droplets to the temperature and humidity measuring unit 26 is suppressed.

[0091] [Fifth Embodiment] Figure 18 is a control block diagram of the humidity measuring device 10. The configuration of the display unit 14 will be explained using the control block diagram of Figure 18.

[0092] The display unit 14 of the humidity measuring device 10 in this embodiment includes a dew point temperature calculation unit 40, a display control unit 52, and a display 54. The display control unit 52 and the display 54 of the display unit 14 of the humidity measuring device 10 in this embodiment are the same as the display control unit 52 and the display 54 of the display unit 14 of the humidity measuring device 10 in the first embodiment.

[0093] The dew point temperature calculation unit 40 receives the temperature of the gas under atmospheric pressure as measured by the temperature and humidity measurement unit 26. The dew point temperature calculation unit 40 receives the humidity of the gas under atmospheric pressure as measured by the temperature and humidity measurement unit 26. The dew point temperature calculation unit 40 receives the pressure of the gas as measured by the pressure measurement unit 92.

[0094] The pressure measuring unit 92 is located outside the humidity measuring device 10. When the humidity measuring device 10 is installed in the piping 36, the pressure measuring unit 92 measures the pressure of the compressed gas flowing through the piping 36. When the humidity measuring device 10 is installed in the dehumidifier 38, the pressure measuring unit 92 measures the pressure of the compressed gas discharged from the dehumidifier 38.

[0095] The dew point temperature calculation unit 40 calculates the dew point temperature of the gas at atmospheric pressure based on the temperature and humidity measurement unit 26's measurement of the gas's temperature at atmospheric pressure and the humidity measurement unit 26's measurement of the gas's humidity at atmospheric pressure. The dew point temperature calculation unit 40 then corrects the dew point temperature of the gas at atmospheric pressure calculated by the dew point temperature calculation unit 40 according to the pressure of the gas measured by the pressure measurement unit 92 to calculate the dew point temperature of the gas at pressure.

[0096] [Effects and Effects] In the humidity measuring device 10 of this embodiment, the dew point temperature calculation unit 40 calculates the dew point temperature of the gas at atmospheric pressure based on the temperature of the gas at atmospheric pressure and the humidity of the gas at atmospheric pressure measured by the temperature and humidity measuring unit 26. The dew point temperature calculation unit 40 corrects the dew point temperature of the gas at atmospheric pressure calculated by the dew point temperature calculation unit 40 according to the pressure of the gas measured by the pressure measuring unit 92 provided outside the humidity measuring device 10, and calculates the dew point temperature of the gas under pressure. As a result, the temperature and humidity measuring unit 26 does not come into contact with the high-pressure gas, and the adhesion of water droplets to the temperature and humidity measuring unit 26 is suppressed.

[0097] [Sixth Embodiment] Figure 19 is a control block diagram of the humidity measuring device 10. The configuration of the display unit 14 will be explained using the control block diagram in Figure 19.

[0098] The display unit 14 of the humidity measuring device 10 in this embodiment includes a dew point temperature calculation unit 40, a display control unit 52, a display 54, and a pressure input unit 94. The display control unit 52 and the display 54 of the display unit 14 of the humidity measuring device 10 in this embodiment are the same as the display control unit 52 and the display 54 of the display unit 14 of the humidity measuring device 10 in the first embodiment.

[0099] The pressure input unit 94 outputs the gas pressure to the dew point temperature calculation unit 40. The gas pressure output by the pressure input unit 94 to the dew point temperature calculation unit 40 may be a value set by the user. The gas pressure output by the pressure input unit 94 to the dew point temperature calculation unit 40 may be a value set by the manufacturer of the humidity measuring device 10 at the time of shipment of the humidity measuring device 10. If the pressure of the compressed gas flowing through the piping 36 is approximately constant, a pre-set pressure may be input to the dew point temperature calculation unit 40. Similarly, if the pressure of the compressed gas discharged by the dehumidifier 38 is approximately constant, a pre-set pressure may be input to the dew point temperature calculation unit 40.

[0100] The dew point temperature calculation unit 40 receives the temperature of the gas under atmospheric pressure as measured by the temperature and humidity measurement unit 26. The dew point temperature calculation unit 40 also receives the humidity of the gas under atmospheric pressure as measured by the temperature and humidity measurement unit 26. The dew point temperature calculation unit 40 also receives the pressure of the gas from the pressure input unit 94.

[0101] The dew point temperature calculation unit 40 calculates the dew point temperature of the gas at atmospheric pressure based on the temperature and humidity measurement unit 26's measurement of the gas's temperature at atmospheric pressure and the humidity measurement unit 26's measurement of the gas's humidity at atmospheric pressure. The dew point temperature calculation unit 40 then corrects the dew point temperature of the gas at atmospheric pressure calculated by the dew point temperature calculation unit 40 according to the gas pressure input from the pressure input unit 94 to calculate the dew point temperature of the gas under pressure.

[0102] [Effects and Effects] In the humidity measuring device 10 of this embodiment, the dew point temperature calculation unit 40 calculates the dew point temperature of the gas at atmospheric pressure based on the temperature of the gas at atmospheric pressure and the humidity of the gas at atmospheric pressure measured by the temperature and humidity measuring unit 26. The dew point temperature calculation unit 40 corrects the dew point temperature of the gas at atmospheric pressure calculated by the dew point temperature calculation unit 40 according to the pressure of the gas input from the pressure input unit 94 to calculate the dew point temperature of the gas under pressure. As a result, the temperature and humidity measuring unit 26 does not come into contact with the high-pressure gas, and the adhesion of water droplets to the temperature and humidity measuring unit 26 is suppressed.

[0103] [Seventh Embodiment] Figure 20 is a control block diagram of the humidity measuring device 10. The configuration of the display unit 14 will be explained using the control block diagram of Figure 20.

[0104] The display unit 14 of the humidity measuring device 10 in this embodiment includes a display control unit 52, a display 54, a replacement determination unit 96, and a correction unit 100. The display control unit 52 and the display 54 of the display unit 14 of the humidity measuring device 10 in this embodiment are the same as the display control unit 52 and the display 54 of the display unit 14 of the humidity measuring device 10 in the first embodiment.

[0105] When the dehumidifier 38 is replaced, the replacement determination unit 96 receives information from the replacement information input unit 98 indicating that the dehumidifier 38 has been replaced. The replacement information input unit 98 is located outside the humidity measuring device 10. The replacement information input unit 98 may also be located on the dehumidifier 38. If information indicating that the dehumidifier 38 has been replaced is input to the replacement determination unit 96 from the replacement information input unit 98, the replacement determination unit 96 determines that the dehumidifier 38 has been replaced. If no information indicating that the dehumidifier 38 has been replaced is input to the replacement determination unit 96 from the replacement information input unit 98, the replacement determination unit 96 determines that the dehumidifier 38 has not been replaced.

[0106] The correction unit 100 receives the humidity of the gas measured by the temperature and humidity measuring unit 26. The correction unit 100 also receives the judgment result determined by the exchange judgment unit 96. The correction unit 100 corrects the humidity measured by the temperature and humidity measuring unit 26 according to the input judgment result.

[0107] Figure 21 is a flowchart showing the flow of the correction process performed in the replacement determination unit 96 and the correction unit 100. The correction process is performed repeatedly at a predetermined cycle.

[0108] In step S1, the replacement determination unit 96 determines whether the dehumidifier 38 has been replaced between the time the process in step S1 was executed in the previous cycle and the time the process in step S1 is executed in the current cycle. The replacement determination unit 96 determines that the dehumidifier 38 has been replaced when it receives information from the replacement information input unit 98 indicating that the dehumidifier 38 has been replaced. If the replacement determination unit 96 determines that the dehumidifier 38 has been replaced (step S1: YES), the correction process proceeds to step S2. If the replacement determination unit 96 determines that the dehumidifier 38 has not been replaced (step S1: NO), the correction process proceeds to step S6.

[0109] In step S2, the correction unit 100 determines whether the humidity of the gas measured by the temperature and humidity measuring unit 26 (measured humidity) is equal to or greater than the first threshold Th1. If the measured humidity is equal to or greater than the first threshold Th1 (step S2: YES), the correction process proceeds to step S7. If the measured humidity is less than the first threshold Th1 (step S2: NO), the correction process proceeds to step S3.

[0110] In step S3, the correction unit 100 determines whether the measured humidity is equal to or greater than the second threshold Th2. If the measured humidity is equal to or greater than the second threshold Th2 (step S3: YES), the correction process proceeds to step S4. If the measured humidity is less than the second threshold Th2 (step S3: NO), the correction process proceeds to step S6. The second threshold Th2 is a value smaller than the first threshold Th1.

[0111] In step S4, the correction unit 100 corrects the measured humidity to obtain a new measured humidity. The correction process then proceeds to step S5. Hereafter, the new measured humidity obtained by the correction unit 100 may be referred to as the corrected humidity.

[0112] In step S5, the replacement determination unit 96 clears the information (dehumidifier replacement information) that the dehumidifier 38 has been replaced, which was input from the replacement information input unit 98. After that, the correction process proceeds to step S6.

[0113] In step S6, the correction unit 100 outputs the measured humidity to the display control unit 52. After that, the correction process is completed.

[0114] In step S7, after it is determined in step S2 that the measured humidity is equal to or greater than the first threshold Th1 (step S2: YES), the correction unit 100 outputs an error signal to the display control unit 52. After that, the correction process ends. If an error signal is input to the display control unit 52, the display control unit 52 controls the display unit 54 to display a message on the display unit 54 prompting the user to replace the temperature and humidity measuring unit 26.

[0115] [Effects and Effects] The humidity-sensing element of the temperature and humidity measuring unit 26 has a humidity-sensing film. The capacitance of the humidity-sensing film changes depending on the amount of moisture contained in the film. The humidity-sensing element measures the humidity of the gas based on the capacitance of the humidity-sensing film.

[0116] As the humidity-sensitive membrane deteriorates, its capacitance, which corresponds to the humidity of the gas, changes. This is caused by factors such as moisture penetration into the membrane and contamination of the membrane. Consequently, as the humidity-sensitive membrane deteriorates, the accuracy of the humidity measured by the temperature and humidity measuring unit 26 decreases.

[0117] Immediately after the dehumidifier 38 is replaced, the humidity of the gas after dehumidification by the dehumidifier 38 is considered to be adjusted to a predetermined humidity according to the dehumidification performance of the dehumidifier 38. If the humidity measured by the temperature and humidity measuring unit 26 is higher than the predetermined humidity, it is considered that the humidity-sensitive film has deteriorated.

[0118] In the humidity measuring device 10 of this embodiment, if the replacement determination unit 96 determines that the dehumidifier 38 has been replaced, and the measured humidity is between the second threshold and the first threshold, the correction unit 100 corrects the measured humidity to obtain the corrected humidity. As a result, even if the humidity-sensitive film is deteriorated, the humidity measuring device 10 can maintain the accuracy of the gas humidity measurement.

[0119] In the humidity measuring device 10 of this embodiment, if the replacement determination unit 96 determines that the dehumidifier 38 has been replaced, and the humidity measured by the temperature and humidity measuring unit 26 is equal to or greater than the first threshold, the display control unit 52 controls the display unit 54 to display a message on the display unit 54 prompting the user to replace the temperature and humidity measuring unit 26. As a result, if the humidity-sensitive film is severely deteriorated, the humidity measuring device 10 can prompt the user to replace the temperature and humidity measuring unit 26.

[0120] [Eighth Embodiment] Figures 22 and 23 show the humidity measuring device 10. The humidity measuring device 10 has a housing 102, a display unit 14, and a joint unit 106. Figures 22 and 23 show the housing 102 and the joint unit 106 in cross-sectional views. Figures 22 and 23 show the display unit 14 in schematic diagrams.

[0121] The housing 102 has a main body 108 and a connecting part 110. The main body 108 has a housing part 112 inside the main body 108. This housing part 112 is a space formed inside the main body 108.

[0122] The humidity measuring device 10 has an electronic circuit board 25. The electronic circuit board 25 is positioned between the main body 108 and the display unit 14. A temperature and humidity measuring unit 26 is mounted on the electronic circuit board 25. The temperature and humidity measuring unit 26 is housed in a housing unit 112. The temperature and humidity measuring unit 26 is an electronic component in which a temperature sensing element and a humidity sensing element are mounted on a single integrated circuit. The temperature sensing element measures the temperature of the gas inside the housing unit 112. The humidity sensing element measures the humidity of the gas inside the housing unit 112. The temperature and humidity measuring unit 26 outputs the measured temperature and humidity of the gas to the display unit 14.

[0123] The connection section 110 has a first connecting pipe 118 and a second connecting pipe 120. The first connecting pipe 118 and the second connecting pipe 120 are connected to the housing section 112. The first connecting pipe 118 and the second connecting pipe 120 are also connected to the joint pipe 122 of the joint section 106, which will be described later. Gas flows between the housing section 112 and the joint pipe 122 through the first connecting pipe 118 and the second connecting pipe 120. The cross-sectional area of ​​the first connecting pipe 118 and the cross-sectional area of ​​the second connecting pipe 120 are different. As shown in Figure 22, the cross-sectional area of ​​the smallest diameter portion of the second connecting pipe 120 is smaller than the cross-sectional area of ​​the smallest diameter portion of the first connecting pipe 118. As shown in Figure 23, the cross-sectional area of ​​the smallest diameter portion of the first connecting pipe 118 may be smaller than the cross-sectional area of ​​the smallest diameter portion of the second connecting pipe 120.

[0124] The joint section 106 has a joint pipe 122 and a pipe fitting section 124 inside it. The joint pipe 122 is formed extending in one direction. Pipe fitting sections 124 are connected to each end of the joint pipe 122. Each of the pipe fitting sections 124 opens to the outside of the joint section 106. The joint section 106 is connected in the middle of the pipe 126 (Figure 24) through which the gas flows. The pipe 126 is connected to each pipe fitting section 124. The joint pipe 122 connects the pipes 126. As a result, gas can flow between the pipes 126 via the joint pipe 122.

[0125] A filter 128 is attached to the fitting pipe 122. The filter 128 is positioned at the connection point between the fitting pipe 122 and the pipe fitting portion 124, which is located upstream of the gas flow in the fitting pipe 122. The fitting pipe 122 has an orifice 130. The cross-sectional area of ​​the smallest diameter portion of the orifice 130 is smaller than the cross-sectional area of ​​other parts of the fitting pipe 122. The orifice 130 is positioned downstream of the filter 128 of the gas flow in the fitting pipe 122. Hereinafter, the portion of the fitting pipe 122 upstream of the orifice 130 may be referred to as the first fitting chamber 132. Also, the portion of the fitting pipe 122 downstream of the orifice 130 may be referred to as the second fitting chamber 134.

[0126] The filter 128 is attached to the upstream end of the fitting pipe 122. The filter 128 makes it possible to remove foreign matter mixed in with the gas flowing into the fitting pipe 122. This prevents foreign matter from entering the fitting pipe 122.

[0127] In the first joint chamber 132, the aforementioned first connecting pipe 118 is connected to the joint pipe 122. In other words, with respect to the gas flow in the joint pipe 122, the first connecting pipe 118 is connected to the joint pipe 122 upstream of the orifice 130, and between the filter 128 and the orifice 130. In the second joint chamber 134, the aforementioned second connecting pipe 120 is connected to the joint pipe 122. In other words, with respect to the gas flow in the joint pipe 122, the second connecting pipe 120 is connected to the joint pipe 122 downstream of the orifice 130.

[0128] Figure 24 shows the state in which the tube 126 is connected to the humidity measuring device 10. The arrows in Figure 24 indicate the flow of gas.

[0129] The orifice 130 causes the pressure in the first joint chamber 132 to be higher than the pressure in the second joint chamber 134. This makes it possible to allow gas from the joint pipe 122 to flow from the first connecting pipe 118 into the housing section 112. The cross-sectional area of ​​the diameter of the second connecting pipe 120 is smaller than that of the diameter of the first connecting pipe 118. Therefore, it is possible to make the pressure in the housing section 112 approximately the same as the pressure in the first joint chamber 132.

[0130] The gas that has passed through the filter 128 flows into the containment section 112. Therefore, it is possible to suppress the entry of foreign matter into the containment section 112.

[0131] The configuration of the display unit 14 is the same as that of the display unit 14 in the first embodiment, third embodiment, fifth embodiment, sixth embodiment, or seventh embodiment.

[0132] [Regarding the accuracy of humidity measurement] The inventors performed computer simulations regarding the humidity in the first joint chamber 132, the second joint chamber 134, and the housing section 112. Figures 25, 26, and 27 show the simulation results. Figure 25 shows the simulation results when the cross-sectional area of ​​the smallest diameter portion of the first connecting pipe 118 is equal to the cross-sectional area of ​​the smallest diameter portion of the second connecting pipe 120. Figure 26 shows the simulation results when the cross-sectional area of ​​the smallest diameter portion of the second connecting pipe 120 is smaller than the cross-sectional area of ​​the smallest diameter portion of the first connecting pipe 118. Figure 27 shows the simulation results when the cross-sectional area of ​​the smallest diameter portion of the first connecting pipe 118 is smaller than the cross-sectional area of ​​the smallest diameter portion of the second connecting pipe 120. In the simulations, gas with a humidity of 88% was introduced into the first joint chamber 132.

[0133] When the cross-sectional area of ​​the smallest diameter portion of the first connecting pipe 118 is equal to the cross-sectional area of ​​the smallest diameter portion of the second connecting pipe 120, as shown in Figure 25, the humidity in the housing section 112 is lower than the humidity in the first joint chamber 132. On the other hand, the humidity in the housing section 112 is higher than the humidity in the second joint chamber 134. In other words, the humidity in the housing section 112 is different from both the humidity in the first joint chamber 132 and the humidity in the second joint chamber 134. Therefore, although the temperature and humidity measuring unit 26 provided in the housing section 112 can measure the humidity of the gas flowing inside the pipe 126, its accuracy is low. In this case, the pressure in the housing section 112 is lower than the pressure in the first joint chamber 132. On the other hand, the pressure in the housing section 112 is higher than the pressure in the second joint chamber 134.

[0134] When the cross-sectional area of ​​the smallest diameter portion of the second connecting pipe 120 is smaller than the cross-sectional area of ​​the smallest diameter portion of the first connecting pipe 118, as shown in Figure 26, the humidity in the housing section 112 is approximately equal to the humidity in the first joint chamber 132. On the other hand, the humidity in the housing section 112 is higher than the humidity in the second joint chamber 134. Therefore, the temperature and humidity measuring unit 26 provided in the housing section 112 can measure the humidity of the gas flowing inside the pipe 126 upstream of the orifice 130 with high accuracy. In this case, the pressure in the housing section 112 is approximately equal to the pressure in the first joint chamber 132. On the other hand, the pressure in the housing section 112 is higher than the pressure in the second joint chamber 134.

[0135] When the cross-sectional area of ​​the smallest diameter portion of the first connecting pipe 118 is smaller than the cross-sectional area of ​​the smallest diameter portion of the second connecting pipe 120, as shown in Figure 27, the humidity in the housing section 112 is approximately equal to the humidity in the second joint chamber 134. On the other hand, the humidity in the housing section 112 is lower than the humidity in the first joint chamber 132. Therefore, the temperature and humidity measuring unit 26 provided in the housing section 112 can measure the humidity of the gas flowing inside the pipe 126 downstream of the orifice 130 with high accuracy. In this case, the pressure in the housing section 112 is approximately equal to the pressure in the second joint chamber 134. On the other hand, the pressure in the housing section 112 is lower than the pressure in the first joint chamber 132.

[0136] [Effects and Effects] The humidity measuring device 10 of this embodiment has a joint section 106 connected in the middle of the pipe 126. The joint piping 122 of the joint section 106 and the housing section 112 of the housing 102 are connected by a first connecting pipe 118 and a second connecting pipe 120. The first connecting pipe 118 is connected to the joint piping 122 upstream of the orifice 130. The second connecting pipe 120 is connected to the joint piping 122 downstream of the orifice 130.

[0137] As a result, the gas flowing through the joint piping 122 is diverted and sent from the first connecting piping 118 to the containment section 112. Therefore, the temperature and humidity measuring unit 26 can measure the humidity of the gas in the containment section 112 under the same pressure as the pipe 126. Consequently, the humidity measuring device 10 can measure the humidity of the gas flowing through the pipe 126. In addition, it is possible to prevent water droplets and other contaminants mixed in the gas flowing through the pipe 126 from entering the containment section 112. As a result, contamination of the temperature and humidity measuring unit 26 can be suppressed.

[0138] Furthermore, in the humidity measuring device 10 of this embodiment, the gas flowing through the pipe 126 flows from the joint pipe 122 through the first connecting pipe 118 into the housing section 112. The gas that has flowed into the housing section 112 returns to the joint pipe 122 through the second connecting pipe 120. Therefore, the gas flowing through the pipe 126 is not discharged to the outside. As a result, the decrease in gas can be suppressed.

[0139] In this embodiment, the humidity measuring device 10 has different cross-sectional areas for the first connecting pipe 118 and the second connecting pipe 120. When the cross-sectional area of ​​the smallest diameter portion of the second connecting pipe 120 is smaller than the cross-sectional area of ​​the smallest diameter portion of the first connecting pipe 118, the temperature and humidity measuring unit 26 can measure the humidity of the gas flowing inside the pipe 126 upstream of the orifice 130 with high accuracy. When the cross-sectional area of ​​the smallest diameter portion of the first connecting pipe 118 is smaller than the cross-sectional area of ​​the smallest diameter portion of the second connecting pipe 120, the temperature and humidity measuring unit 26 can measure the humidity of the gas flowing inside the pipe 126 downstream of the orifice 130 with high accuracy.

[0140] [Ninth Embodiment] Figure 28 shows the humidity measuring device 10. The humidity measuring device 10 has a housing 102, a display unit 14, and a joint unit 106. Figure 28 shows the housing 102 and the joint unit 106 in cross-sectional view. Figure 28 shows the display unit 14 in schematic view.

[0141] A flow sensor 136 is mounted on the electronic circuit board 25. The flow sensor 136 is housed in the housing section 112 of the housing 102. The flow sensor 136 detects the flow rate of the gas flowing through the housing section 112. The flow rate of the gas flowing through the tube 126 can be determined from the flow rate of the gas flowing through the housing section 112. The flow sensor 136 is composed of a sensor, a thermistor, platinum, etc. The sensor is made of MEMS (Micro Electro Mechanical Systems). The other configurations of the humidity measuring device 10 of this embodiment are the same as those of the humidity measuring device 10 of the eighth embodiment.

[0142] [Effects and Effects] In the humidity measuring device 10 of this embodiment, a flow sensor 136 is housed in the housing section 112 of the housing 102. This makes it possible to determine the flow rate of the gas flowing through the pipe 126.

[0143] [Tenth Embodiment] Figure 29 shows the humidity measuring device 10. The humidity measuring device 10 has a housing 102, a display unit 14, and a joint unit 106. Figure 29 shows the housing 102 and the joint unit 106 in cross-sectional view. Figure 29 shows the display unit 14 in schematic view.

[0144] Filters 128 and 138 are attached to the fitting pipe 122. Filter 138 is positioned on the opposite side of the orifice 130 from filter 128. Filter 128 is attached to the connection between fitting pipe 122 and pipe fitting 124. Filter 138 is attached to the connection between fitting pipe 122 and pipe fitting 124.

[0145] Filter 128 is attached to one end of the fitting pipe 122, and filter 138 is attached to the other end of the fitting pipe 122. This makes it possible to remove foreign matter mixed in the gas flowing into the fitting pipe 122 by filter 128 or filter 138, even when the direction of gas flow is switched. This prevents foreign matter from entering the fitting pipe 122.

[0146] Furthermore, the present invention is not limited to the embodiments described above, and various configurations can be taken without departing from the spirit of the invention.

[0147] [Technical ideas derived from the embodiments] The technical concepts that can be understood from the above embodiments are described below.

[0148] A humidity measuring device (10) for measuring the humidity of a gas, comprising: a measuring unit (26) having a temperature-sensing element for measuring temperature and a humidity-sensing element for measuring humidity; a housing (102) having a housing (112) in which the measuring unit is housed; a display unit (14) having a display (54) fixed to the housing; and a joint piping (122) connected in the middle of a pipe (126) through which the gas flows, allowing the gas to flow between the pipes, wherein the joint piping has an orifice (130) and a filter (128) attached to the joint piping, and the housing has a first pipe (118) and a second pipe (120) connecting the joint piping and the housing, allowing the gas to flow between the joint piping and the housing. Thus, the humidity measuring device can measure the humidity of a gas flowing through a pipe.

[0149] In the humidity measuring device described above, the cross-sectional area of ​​the first pipe and the cross-sectional area of ​​the second pipe may be different. This allows the humidity measuring device to measure the humidity of the gas flowing through the pipe.

[0150] The humidity measuring device described above may include a flow sensor (136) for measuring the flow rate of the gas, and the flow sensor may be housed in the housing. This allows the humidity measuring device to determine the flow rate of the gas flowing through the tube.

[0151] In the humidity measuring device described above, the display unit may have a display control unit (52) that controls the display to display on the display at least one of the dew point temperature of the gas, which is calculated based on the temperature of the gas measured by the temperature sensing element and the humidity of the gas measured by the humidity sensing element, and the humidity of the gas measured by the humidity sensing element. This allows the user to check the humidity of the gas and the dew point temperature of the gas at the location where the humidity measuring device is installed. [Explanation of symbols]

[0152] 10...Humidity measuring device 14...Display section 26...Temperature and humidity measurement unit (measurement unit) 52...Display control unit 54...Display unit 102...Enclosure 112...Housing section 118...First connecting pipe (first pipe) 120...Second connecting pipe (second pipe) 128...Filter 130... Orifice 136... Flow sensor

Claims

1. A humidity measuring device for measuring the humidity of a gas, A measuring unit having a temperature-sensing element for measuring temperature and a humidity-sensing element for measuring humidity, A housing having a housing section in which the measuring unit is housed, A display unit having a display device and fixed to the housing, A joint pipe connected in the middle of a pipe through which the gas flows, which allows the gas to flow between the pipes, Equipped with, The aforementioned joint piping has an orifice, A filter is attached to the aforementioned fitting pipe. The housing has a first pipe and a second pipe that connect the joint piping and the housing, and allow the gas to flow between the joint piping and the housing, and is a humidity measuring device.

2. In the humidity measuring device according to claim 1, A humidity measuring device in which the cross-sectional area of ​​the first pipe and the cross-sectional area of ​​the second pipe are different.

3. In the humidity measuring device according to claim 1 or 2, It has a flow sensor for measuring the flow rate of the aforementioned gas, The flow sensor is a humidity measuring device housed in the aforementioned housing.

4. In the humidity measuring device according to claim 1 or 2, A humidity measuring device comprising a display control unit that controls the display to display on the display at least one of the dew point temperature of the gas calculated based on the temperature of the gas measured by the temperature sensing element and the humidity of the gas measured by the humidity sensing element, and the humidity of the gas measured by the humidity sensing element.

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