JPH10267803A - Air sampling-type environment monitoring sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase a suction flow rate as a whole without increasing the flow rate of the air and to expand a monitoring space by a method wherein the flow passage of the air is branched into a plurality of branch flow passages, an air resistance is given to one branch flow passage out of them and the concentration of the component of fine particles, a gas, an odor or the like in the air which is sucked in another flow passage is detected. SOLUTION: A monitoring sensor body 101 is provided with a flow passage C1 and a branch means D1 which are connected to a pipe 3, with branch flow passages C11, C12, with air-resistance giving means 11, 12, with concentration detecting means 21, 22, with a suction device 31, with a suction hole 1 and with an evacuation hole H2. The branch means D1 is a means by which the flow passage of the sucked air is branched into a plurality of branch flow passages. The concentration detecting means 21, 22 are installed at one out of the plurality of branch flow passages so as to detect one concentration of the component of fine particles, a gas or an odor in the sucked air. Then, by using one common suction device 31, resistance values in the resistance giving means 11, 12 are balanced, and the flow rate of the air which flows in the respective branch flow passages C11, C12 is regulated to a flow rate which is optimum for the respective concentration detecting means 21, 22.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air sampling system for sucking air in a monitored space and detecting the concentration of fine particles, gas and odor in the sucked air in case of an abnormal situation such as a fire. It relates to an environmental monitoring sensor.

[0002]

2. Description of the Related Art As a conventional air sampling type environmental monitoring sensor, a sensor that detects fine particles generated by an abnormal situation such as a fire by using optical scattering has been put into practical use.
Devices that detect abnormalities using gas or odor have been devised.

For example, in the method of counting the optical scattering pulses of the fine particles in the sucked air, since the detection is performed in the condensed minute space, the volume of the detection space is small, and the flow rate of the passing air is limited. To overcome this shortcoming,
When the flow rate is increased, a counting error occurs due to insufficient response of the light receiving circuit and overlapping of particles in a high concentration region.

On the other hand, when a plurality of different detection principles are used at the same time, air in the monitoring space is sucked by a suction device from an air sampling pipe installed in the monitoring space, and the sucked air is introduced into a plurality of concentration detecting means. And simultaneously detect fine particles, gas, odor and the like in the air. When installing a plurality of concentration detection means in this way, by sharing the detection space, or by connecting the detection means in series,
Since the same flow rate of air is used, the suction capacity of the air sampling type environment monitoring sensor as a whole is limited by the flow rate of the concentration detecting means having the minimum flow rate upper limit.

FIG. 9 is a diagram showing a conventional air sampling type environment monitoring sensor ASS.

A conventional air sampling type environment monitoring sensor ASS is an air sampling type environment monitoring sensor which sucks air in a monitoring space and detects the concentration of fine particles, gas, odor components and the like in the sucked air. Tube 1
, A pipe 3, and a monitoring sensor main body 100.

[0007] The air sampling pipe 1 is installed in the monitoring space, has a plurality of sampling holes 2, and the pipe 3 is a pipe for sending air sucked from the plurality of sampling holes 2 to the monitoring sensor main body 100. The monitoring sensor body 10
Numeral 0 has one flow path C connected to the pipe 3, two concentration detection means 21a and 22a, a suction device 31, a suction hole H1, and an exhaust hole H2. The two concentration detecting means 21a and 22a are connected in series.

[0008]

In this case, the amount of air passing through the density detecting means 21a, 22a is larger than the air resistance of the density detecting means 21a or the air resistance of the density detecting means 22a. There is a problem that it is governed by the amount of air.

Further, the conventional air sampling type environment monitoring sensor body 100 itself has difficulty in obtaining a large suction flow rate and the capability itself of the suction device itself is generally poor. In order to shorten the time, there is a problem that the distance from the monitoring space to the air sampling type environment monitoring sensor is limited, and similarly, there is a problem that the size of the monitoring space is limited.

FIG. 10 shows a conventional example in which other equipment such as an air conditioner AC which sucks in a large flow rate is used to expand the monitoring space, and air branched from these is monitored by the monitoring sensor body 100. FIG.

However, when the environmental monitoring sensor is used for monitoring a serious abnormality such as fire detection, a condition is required that the reliability of other equipment used must be equal or higher.
For example, even if the environmental monitoring sensor main body 100 can be operated with a standby power supply at the time of a power outage, there is a problem that if the air conditioner AC, which is another facility used, is stopped, abnormality monitoring cannot be performed.

FIG. 11 is a diagram showing a conventional method of indirectly measuring a flow rate using a hot wire anemometer.

The conventional method shown in FIG. 11 has a problem that the wind speed in the pipe is not always uniform, and it is difficult to improve the accuracy. In addition, if the flow rate measuring means is provided as described above in order to monitor the operation status of the environment monitoring sensor, the suction capacity is reduced. Is extremely limited.

Further, an air filter may be provided in the sensor for the purpose of preventing fouling. However, if the air filter is used in an environment with more severe contamination than expected, clogging occurs quickly. The clogging of the air filter can be detected in principle by measuring its air resistance, but since the flow rate measuring means serving as a reference for calculating the air resistance is poor as described above,
It has not been put to practical use.

In other words, the conventional air sampling type environment monitoring sensor has a problem that the suction capability of the entire sensor is limited due to the air resistance of the concentration detecting means itself and restrictions on the principle of concentration detection.

The present invention provides an air sampling type environment monitoring sensor that can increase the suction flow rate of the entire air sampling type environment monitoring sensor and increase the monitoring space without increasing the flow rate of air passing through the concentration detecting means. It is intended to provide.

Further, the present invention provides an air sampling type air conditioner which can optimize the flow rate of air passing through the concentration detecting means for each concentration detecting means without reducing the suction flow rate of the entire environment monitoring sensor. It is an object to provide an environmental monitoring sensor.

[0018]

According to the present invention, there is provided a branching means for branching a flow path of air sucked from a monitoring space into a plurality of branch flow paths, and at least one branch flow path among the plurality of branch flow paths. Air resistance applying means for applying a predetermined air resistance,
Air sampling type environment monitoring provided in at least one of the plurality of branch passages and having a concentration detecting means for detecting the concentration of at least one component among fine particles, gas and odor in the sucked air. It is a sensor.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an air sampling type environment monitoring sensor A according to a first embodiment of the present invention.
It is a figure showing SS1.

Air sampling type environmental monitoring sensor ASS
Reference numeral 1 denotes an air sampling type environment monitoring sensor that sucks air in a monitoring space and detects the concentration of at least one of fine particles, gas, and odor components in the sucked air. , A monitoring sensor main body 101.

The air sampling pipe 1 is installed in a monitoring space and has a plurality of sampling holes 2. Piping 3
This is a tube for sending air sucked from the plurality of sampling holes 2 to the monitoring sensor main body 101.

The monitoring sensor main body 101 includes one flow path C1 connected to the pipe 3, a branching means D1, and a flow path C1.
Flow paths C11, C branched by the branch means D1
12, air resistance applying means 11 and 12, concentration detecting means 21 and 22, a suction device 31, a suction hole H 1, and an exhaust hole H 2. The branch flow path C11 is provided with the air resistance applying means 11 and the concentration detecting means 21 in series, and the branch flow path C12 is provided with the air resistance applying means 12 and the concentration detecting means 22 in series.

The branching means D1 is an example of a branching means for branching the flow path of the sucked air into a plurality of branching flow paths. Is an example of an air resistance applying means for applying a predetermined air resistance, wherein the concentration detecting means 21 and 22 are provided in at least one of the plurality of branch flow paths, and the air resistance applying means 11 and 12 are provided. This is an example of a concentration detecting unit that is connected in series and detects the concentration of at least one of fine particles, gas, and odor components in the sucked air. The exhaust hole H2 is a hole for discharging the sucked air to the outside of the air sampling type environmental monitoring sensor ASS1.

The flow rate of the air flowing through each of the branch passages C11 and C12 is determined by the balance of the resistance values of the air resistance applying means 11 and 12 by using one common suction device 31 and the concentration detecting means 21. The flow rate is adjusted to the optimum flow rate for 22.

Next, each flow path C11 in the above embodiment,
The flow rate passing through C12 will be described.

FIG. 2 is a sectional view showing an orifice as the air resistance applying means 11 used in the above embodiment.

The orifice as the air resistance applying means 11 is an example of the air resistance applying means 11 and 12, and is constituted by a shielding plate having an opening. The flow rate Q passing through the orifice is approximated by Q = K · S · (ΔP) ^1/2 . Here, S is the opening area of the orifice, K is a proportional constant, and ΔP is the pressure difference before and after the orifice.

FIG. 3 shows the pressure difference at the orifice.
FIG. 9 is a characteristic diagram showing data obtained by actually measuring flow characteristics.

If the relationship between the pressure difference and the flow rate is stable, the air resistance applying means 11 and 12 may be constituted by means other than the orifice.

FIG. 4 shows each flow path C1 in the above embodiment.
1. Pressure difference-flow rate characteristics for each C12 and monitoring sensor body 1
FIG. 11 is a characteristic diagram showing an overall pressure difference-flow rate characteristic of No. 01.

In FIG. 4, the characteristic CH1 is determined by the flow path C11.
The characteristic CH2 is the pressure difference-flow characteristic in the flow path C12, and the characteristic CHt
Is a pressure difference-flow rate characteristic of the entire monitoring sensor main body 101.

Since the concentration detecting means 21 and 22 also have air resistance, the pressure difference in each characteristic is the pressure difference between the inlet of the air resistance applying means 11 and the outlet of the concentration detecting means 21. , Air resistance applying means 12
Is the pressure difference between the inlet of the sensor and the outlet of the concentration detecting means 22.

The characteristics CH1, CH2 and CH
The pressure difference at each of t is the same because the measurement point of the pressure difference is the same, and the flow rate in the characteristic CHt of the entire monitoring sensor main body 101 is:
This is the sum of the flow rate in the characteristic CH1 and the flow rate in the characteristic CH2.

Therefore, the air resistance applying means 11 and 12
By adjusting the values of the air resistance at each other,
A desired ratio of the total suction flow rate of the air sampling type environmental monitoring sensor ASS1 is determined by each of the concentration detecting means 21 and 22.
To the concentration detection means 21,
The flow rate ratio of the air passing through each of the 22 can be controlled.

That is, in the above embodiment, the flow rate of the air passing through the density detecting means 21 and 22 is changed for each of the density detecting means 21 and 22 without reducing the suction flow rate of the entire air sampling type environment monitoring sensor ASS1. Can be optimized.

FIG. 5 is a diagram showing an air sampling type environment monitoring sensor ASS2 according to a second embodiment of the present invention.

Air sampling type environmental monitoring sensor ASS
2 is a monitoring sensor main body 1 in which the concentration detecting means 22 is deleted in the air sampling type environment monitoring sensor ASS1.
02, that is, the density detecting means 22
Is the same as the configuration of the air sampling type environment monitoring sensor ASS1 except that is changed to a direct connection pipe. In addition, piping 3
Is divided into branch flow paths C21 and C22 by a branching means D2, and the branch flow path C21
, An air resistance applying means 11 and a concentration detecting means 21 are provided in series, and only an air resistance applying means 12 is provided in a branch channel C22.

Air sampling type environmental monitoring sensor ASS
In 2, when the air resistance of the air resistance applying means 12 is set smaller than a certain value, the air resistance of the entire air sampling type environment monitoring sensor ASS2 can be made smaller than that of the concentration detecting means 21 alone. Therefore, by removing the concentration detecting means from the branch flow path C22 and making the air resistance of the air resistance applying means 12 smaller than the certain value, the value of the air resistance in the branch flow path becomes smaller. Without changing, the air resistance of the entire air sampling type environment monitoring sensor ASS2 can be reduced, and the suction flow rate from the monitoring space can be increased. As described above, by increasing the suction flow rate from the monitoring space, the air sucked from the monitoring space quickly reaches the concentration detecting means 21 and shortens the response time of the air sampling type environment monitoring sensor to the concentration change in the monitoring space. be able to.

That is, since the air sampling type environment monitoring sensor ASS2 is constituted by only the air resistance applying means 12 by removing the concentration detecting means from the branch flow path C22, there is no restriction on the flow rate of the concentration detecting means. The flow rate of the flow path can be increased, while the flow rate of the branch flow path C21 provided with the concentration detecting means 21 is:
It can be properly maintained by the air resistance inherent in the flow path.

Further, the suction flow rate of the entire air sampling type environment monitoring sensor ASS2 can be increased without increasing the flow rate of the air passing through the concentration detecting means 21 and 22, so that the suction capacity of the suction device 31 is not increased. However, the monitoring space can be expanded.

FIG. 6 is a view showing an air sampling type environment monitoring sensor ASS3 according to a third embodiment of the present invention.

Air sampling type environmental monitoring sensor ASS
3, an air sampling type environment monitoring sensor ASS2 is provided with a flow rate detecting means 41 having a predetermined air resistance instead of the air resistance applying means 11 and having a predetermined air resistance instead of the air resistance applying means 12. The monitoring sensor body 103 provided with the flow rate detecting means 42 is used. In addition, one flow path C3 connected to the pipe 3
Is branched into branch flow paths C31 and C32 by a branch means D3, a flow rate detection means 41 and a concentration detection means 21 are provided in series in the branch flow path C31, and only a flow rate detection means 42 is provided in the branch flow path C32. I have.

Since the flow rate detecting means 41 and 42 have a predetermined air resistance, the flow rate detecting means 41 and 42 also have a function of an air resistance applying means.

By the way, in the conventional air sampling type environment monitoring sensor ASS shown in FIG. 9, when the flow detecting means is inserted into the flow path C for detecting the flow, the flow detecting means has an air resistance. The overall air resistance is increased, which reduces the suction flow. However, the air sampling type environmental monitoring sensor ASS
1, in ASS2, air resistance applying means 11, 12
Flow detecting means 4 having an air resistance value not higher than the air resistance value
When the air sampling type environment monitoring sensors ASS1 and ASS2 are used, the suction flow rate of the air sampling type environment monitoring sensors ASS1 and ASS2 can be prevented from decreasing.
1. The flow rate of the entire ASS2 can be detected.

FIG. 7 is a diagram showing an air sampling type environment monitoring sensor ASS4 according to a fourth embodiment of the present invention.

Air sampling type environmental monitoring sensor ASS
Reference numeral 4 denotes a state before the suctioned air reaches the concentration detecting means 21 in the air sampling type environment monitoring sensor ASS2 and in the branch flow path C41 (the inflow end of the branch flow path C41 and the concentration detecting means 21). In the meantime, the monitoring sensor body 104 in which the air filter 51 is inserted is used. In addition, one flow path C4 connected to the pipe 3 is branched into branch flow paths C41 and C42 by a branch means D4, and the air filter 51, the air resistance applying means 11, and the concentration detection means 21 are provided in the branch flow path C41. Only the air resistance applying means 12 is provided in series and provided in the branch flow path C42.

Air sampling type environmental monitoring sensor ASS
In 4, since the air that has passed through the air filter 51 is supplied to the concentration detecting means 21, the contamination in the concentration detecting means 21 is prevented, and the air that has passed through the air filter 51 is the entire sampling type environment monitoring sensor ASS 4. Is a part of the air to be sucked, the amount of the contaminants collected in the air filter 51 is reduced, and the period until the air filter 51 is clogged can be extended.

In the conventional air sampling type environmental monitoring sensor ASS, when an air filter is inserted into the flow path C,
The air resistance of the entire monitoring sensor body 100 increases, and the suction flow rate decreases. On the other hand, in the air sampling type environmental monitoring sensor ASS4, if the air resistance in the air resistance applying means 11 and 12 is reduced by the air resistance of the air filter 15 to be inserted, the suction flow rate of the entire air sampling type environmental monitoring sensor ASS4 is reduced. It does not decline.

The air sampling type environmental monitoring sensor ASS4 is replaced with the air sampling type environmental monitoring sensor ASS4.
1. It may be applied to ASS3. That is, in the air sampling type environment monitoring sensors ASS1 and ASS3, before the sucked air reaches the concentration detecting means 21 and 22, the air filter 51 is provided in the branch flow path where the concentration detecting means 21 and 22 are provided. May be inserted.

FIG. 8 is a view showing an air sampling type environment monitoring sensor ASS5 according to a fifth embodiment of the present invention.

Air sampling type environmental monitoring sensor ASS
5 is a differential pressure detecting means 61 between both ends of the air filter 51 in the air sampling type environment monitoring sensor ASS4.
Is added, the air sampling type environmental monitoring sensor ASS
The monitoring sensor body 105 provided with the flow detecting means 41 used in 3 and the calculating means 71 is used.

One flow path C5 connected to the pipe 3 is branched into branch flow paths C51 and C52 by a branch means D5, and the air flow filter 51, the flow rate detection means 41, and the concentration detection means 21 are provided in the branch flow path C51. Are provided in series, and a differential pressure detecting means 61 is provided in parallel with the air filter 51,
Only the air resistance applying means 12 is provided in the branch channel C42.

The calculating means 71 calculates the air resistance value of the air filter 51 based on the value of the differential pressure detected by the differential pressure detecting means 61 and the suction flow rate detected by the flow rate detecting means 41.

Air sampling type environmental monitoring sensor ASS
In 5, when the air filter 51 is clogged,
Its air resistance increases. Therefore, in the air sampling type environment monitoring sensor ASS5, the calculating means 71
The clogging of the air filter 51 can be detected on the basis of the change in the air resistance value calculated by.

In the above embodiment, the air resistance applying means 11 and 12 are constituted by orifices.
When one flow path is branched into a plurality of branch flow paths, if the branch flow path is narrowed, a predetermined air resistance is generated, and when the flow path branches, the air resistance applying means 11 and 12 are provided. The branching means in the case also has the function of the air resistance applying means. Instead of providing an orifice, a thin tube (a Venturi tube, a nozzle, or the like) may be used for a part of the flow path.

Further, it is not necessary to provide the air resistance applying means in all of the plurality of branch flow paths, and it is sufficient to provide the air resistance applying means in at least one of the plurality of branch flow paths.

[0057]

According to the present invention, the suction flow rate of the entire air sampling type environment monitoring sensor can be increased without increasing the flow rate of the air passing through the concentration detecting means, and the monitoring space can be expanded. Play.

[Brief description of the drawings]

FIG. 1 is a diagram showing an air sampling type environment monitoring sensor ASS1 according to a first embodiment of the present invention.

FIG. 2 is a sectional view showing an orifice serving as an air resistance applying means 11 used in the embodiment.

FIG. 3 is a characteristic diagram showing data obtained by actually measuring a pressure difference-flow rate characteristic at the orifice.

FIG. 4 is a characteristic diagram showing a pressure difference-flow rate characteristic for each of the flow paths C11 and C12 and the pressure difference-flow rate characteristic of the entire monitoring sensor main body 101 in the embodiment.

FIG. 5 is a diagram showing an air sampling type environment monitoring sensor ASS2 according to a second embodiment of the present invention.

FIG. 6 is a diagram showing an air sampling type environment monitoring sensor ASS3 according to a third embodiment of the present invention.

FIG. 7 is a diagram showing an air sampling type environment monitoring sensor ASS4 according to a fourth embodiment of the present invention.

FIG. 8 is a diagram showing an air sampling type environment monitoring sensor ASS5 according to a fifth embodiment of the present invention.

FIG. 9 shows a conventional air sampling type environmental monitoring sensor AS.
It is a figure showing S.

FIG. 10 is a diagram showing a conventional example in which other equipment such as an air-conditioning equipment AC sucking at a large flow rate is used to expand a monitoring space, and air branched from these is monitored by a monitoring sensor body 100. .

FIG. 11 is a diagram showing a conventional method of indirectly measuring a flow rate using a hot wire anemometer.

[Explanation of symbols]

ASS1 to ASS5 ... air sampling type environment monitoring sensor, 101 to 105 ... monitoring sensor body, C1 to C5 ... flow path, C11, C21, C31, C41, C51 ... branch flow path, C12, C22, C32, C42, C52 ... Branch flow path, 1: sampling pipe, 11, 12: air resistance applying means, 21, 22: concentration detecting means, 31: suction device, 41, 42: flow detecting means, 51: air filter, 61: differential pressure detecting means , 71 ... arithmetic means.

Claims (6)

[Claims] 1. An air sampling type environment monitoring sensor for sucking air in a monitoring space and detecting a concentration of at least one component among fine particles, gas and odor in the sucked air, wherein: Branching means for branching a plurality of branch flow paths; air resistance applying means for applying a predetermined air resistance to at least one of the plurality of branch flow paths; The fine particles, gas, and the like in the sucked air provided in at least one of the branch flow paths;
An air sampling type environment monitoring sensor, comprising: concentration detection means for detecting the concentration of at least one component of the odor. 2. The common one according to claim 1, wherein all of the air flowing through each of the branch flow paths is sucked.
A suction device is provided, and the air resistance applying means is a means for adjusting a flow rate of air flowing through each of the branch flow paths to a flow rate optimal for each of the concentration detecting means. Environmental monitoring sensor. 3. The flow path according to claim 1, wherein at least one of the plurality of branch flow paths is provided with the air resistance applying means, but is not provided with the concentration detecting means. An air sampling type environment monitoring sensor characterized by the following. 4. The air sampling type environment monitoring sensor according to claim 1, wherein at least one of the plurality of air resistance applying means is a flow rate measuring means. 5. The air filter according to claim 1, wherein an air filter is provided between an inflow end of the branch flow path and the concentration detecting means. Air sampling type environmental monitoring sensor. 6. The air pressure measured by the pressure difference measuring means according to claim 5, wherein a pressure difference measuring means for measuring a pressure difference before and after the air filter; a flow rate measuring means for measuring a flow rate of the air filter; An air resistance calculating means for calculating an air resistance of the air filter based on a pressure difference of the filter and a passing flow rate measured by the flow rate measuring means.