JP6212333B2 - Airflow control device and method - Google Patents

Description

  The present invention relates to an air volume control device and method used in a fume hood system.

  Conventionally, in chemical experiments, biochemical substances that are harmful to the human body are often generated in the course of experimental work. One device that prevents the diffusion of these biochemical substances into the room and prevents contamination of the human body is a fume hood. In general, the fume hood is provided with an enclosure (enclosure) with a sash that can be opened and closed vertically or horizontally, and a laboratory worker can access the enclosure from the sash (see, for example, Patent Document 1). .

  The fume hood is connected to a local exhaust duct that removes biochemicals in order to prevent workers during work from being exposed to harmful biochemicals, and the local exhaust duct contains local exhaust from the fume hood. A local exhaust valve is provided to adjust the air volume. Further, the chamber in which the fume hood is installed is provided with an air supply valve for adjusting the air volume of the air supplied to the chamber and a general exhaust valve for adjusting the air volume of the general exhaust from this chamber (for example, , See Patent Document 1).

  FIG. 7 is a diagram showing a main part of a conventional fume hood system. In the figure, 101 is a fume hood installed in the chamber 100, 102 is a local exhaust duct connected to the fume hood 101, and 103 adjusts the air volume of the local exhaust EX from the fume hood 101 through the local exhaust duct 102. A local exhaust valve 104 is a controller attached to the local exhaust valve 103, a sash 105 is provided on the front surface of the fume hood 101 so as to be opened and closed, and a sash sensor 106 detects the position of the sash 105.

  107 (107A, 107B) is an air supply duct connected to the chamber 100, and 108 (108A, 108B) is an air volume of the air supply (SA1, SA2) to the chamber 100 via the air supply duct 107 (107A, 107B). , 109 (109A, 109B) is a controller attached to the supply valve 108 (108A, 108B), 110 is a general exhaust duct connected to the chamber 100, 111 is a chamber through the general exhaust duct 110 100 is a general exhaust valve for adjusting the flow rate of the general exhaust GEX from 100, 112 is a controller attached to the general exhaust valve 111, 113 is a flow rate of the local exhaust valve 103, the supply valve 108 (108A, 108B) and the general exhaust valve 111 Is an air volume control device for controlling the air flow.

In this fume hood system, the air volume control device 113 is a fume that maintains the wind speed (surface wind speed) of the opening surface of the sash 105 at a predetermined speed (constant wind speed) according to the position of the sash 105 detected by the sash sensor 106. calculates the air volume Q _EX of local exhaust from the hood 101, depending on the air volume Q _EX of the computed local exhaust, topical from common exhaust airflow and fume hood 101 from air supply airflow and the chamber 100 to the chamber 100 The air volume Q _IN1 and Q _IN2 of the air supplied from the air supply valves 108A and 108B and the air volume Q _GEX of the general exhaust from the general exhaust valve 111 are set so that the exhaust air volume is balanced with a constant air volume difference (offset air volume). calculated, as airflow Q _EX of the computed local exhaust, supply air volume Q _IN1, Q _IN2 and the general exhaust air volume Q _GEX is obtained, the controller 104 109A, 109B, 112 through, for controlling the air volume of the local air flow of the exhaust valve 103, intake valve 108A, 108B of the air volume and general exhaust valve 111.

Note that the supply air volumes Q _IN1 and Q _IN2 for the supply valves 108A and 108B are Q _IN1 = Q _IN × 0.5, Q when the air volume of the supply air SA (SA1 + SA2) to the chamber 100 is Q _{IN. It is calculated as IN2} = _QIN x 0.5. That is, Q _IN1 and Q _IN2 are obtained by proportionally dividing Q _IN at a ratio of 50%.

JP 2012-237527 A

  In such a fume hood system, when even one air supply valve 108 fails, the remaining air supply valve 108 cannot follow the opening and closing of the local exhaust valve 103, and the air volume balance cannot be maintained. there were.

[Example 1]
For example, it is assumed that the supply valves 108A and 108B are balanced by 25% air volume, the local exhaust valve 103 is balanced by 25% air volume, and the general exhaust valve 111 is balanced by 25% air volume (see FIG. 8A). Has become fully closed, the air supply valve 108A has 0% airflow, the air supply valve 108B has 25% airflow, the local exhaust valve 103 has 25% airflow, and the general exhaust valve 111 has 25% airflow. (See FIG. 8 (b)), it becomes impossible to maintain the air volume balance between the air supply and the exhaust.

[Example 2]
For example, assume that the supply valves 108A and 108B are balanced by 25% air volume, the local exhaust valve 103 is 25% air volume, and the general exhaust valve 111 is 25% air volume (see FIG. 9A). Suppose that it breaks down and stops moving at that position. In this state, the sash 105 is closed and the local exhaust valve 103 is set to 0% air volume. In this case, since the air volume of the air supply valve 108A remains 25% (see FIG. 9B), that is, the air volume of the air supply valve 108B is set to 12.5%. Since the air volume remains 25%, the air volume balance between the supply air and the exhaust air cannot be maintained.

  In addition, such a fume hood system has the following problems. When a large number of fume hoods 101 are installed in the chamber 100, the air supply valves 108 (108A and 108B) that balance the air flow with respect to the opening and closing of the sashes 105 of the individual fume hoods 101 increase the number of operations. . When the number of operations of the supply valve 108 (108A, 108B) increases, the opening position of the actuator or the supply valve 108 (108A, 108B) used to open and close the supply valve 108 (108A, 108B) is detected. Therefore, the operating life of components such as a potentiometer (variable resistor) used for this is shortened (the supply air valves 108A and 108A have the same number of opening and closing because the set air volume is apportioned).

The present invention has been made to solve such a problem, and an object of the present invention is to provide an air volume control device capable of maintaining an air volume balance even if an air supply valve fails. is there.
It is another object of the present invention to provide an air volume control device that can maintain the air volume balance even if the air supply valve breaks down and can extend the operating life of the air supply valve.

In order to achieve such an object, the present invention provides an air supply valve that adjusts the air volume of air supplied to a room in which a fume hood is installed, a general exhaust valve that adjusts the air volume of general exhaust from the room, a fume A sash position detecting means for detecting a position of a sash provided to be openable and closable on a front surface of the fume hood in a fume hood system having a local exhaust valve for adjusting a local exhaust air volume from a hood. The local exhaust air volume calculating means for calculating the air volume of the local exhaust from the fume hood so as to maintain the wind speed of the opening surface of the sash at a predetermined speed according to the position of the sash detected by the sash position detecting means, Depending on the local exhaust air volume from the fume hood calculated by the local exhaust air volume calculation means, the air supply volume to the room and the general exhaust air volume from the room A balance air volume calculating means for calculating the air volume of the supply air from the air supply valve and the air volume of the general exhaust from the general exhaust valve so that the local exhaust air volume from the fume hood and the local exhaust air volume are balanced with a constant air volume difference; The local exhaust valve air volume, the air supply valve air volume, and the general exhaust gas so that the local exhaust air volume calculated by the exhaust air volume calculating means, the supply air volume calculated by the balance air volume calculating means, and the general exhaust air volume can be obtained. Air flow control means for controlling the air flow of the valve and whether or not a failure has occurred in the air supply valve . If it is determined that a failure has occurred in the air supply valve, the general exhaust is used instead of the air supply valve in which the failure has occurred. And an air volume control continuation means for operating the valve and continuing the air volume control by the air volume control means.

In the present invention, the air volume control continuation means, when a failure occurs in the air supply valve, operates the general exhaust valve instead of the air supply valve in which the failure has occurred, and air volume control by the air volume control means (hereinafter referred to as air volume balance control). Ru allowed to continue with the call).

According to the present invention, it is determined whether or not a failure has occurred in the supply valve, and when it is determined that a failure has occurred in the supply valve, the general exhaust valve is operated instead of the supply valve in which the failure has occurred. since so as to continue the air volume balance control, even if the air supply valve has failed and it is possible to maintain the air volume balance.

It is a figure which shows the principal part of the fume hood system using one Embodiment (Embodiment 1) of the air volume control apparatus which concerns on this invention. It is a figure explaining operation | movement of the air volume control apparatus in the case of using the air supply valve which has not failed in this fume hood system as an alternative valve. It is a figure explaining operation | movement of the air volume control apparatus in the case of using a general exhaust valve as a substitute valve in this fume hood system. It is a figure which shows the example of application to a fume hood system which has only one air supply valve. It is a figure explaining operation | movement of the air volume control apparatus performed by using a general exhaust valve as a substitute valve in this fume hood system. It is a figure which shows the principal part of the fume hood system using other embodiment (Embodiment 2) of the air volume control apparatus which concerns on this invention. It is a figure which shows the principal part of the conventional fume hood system. It is a figure explaining operation | movement (example 1) of the air volume control apparatus when an air supply valve fails in this fume hood system. It is a figure explaining operation | movement (example 2) of the air volume control apparatus when an air supply valve fails in this fume hood system.

Hereinafter, the present invention will be described in detail with reference to the drawings. In addition, in the following description, what is not included in the scope of the right of the present invention is described as an embodiment, but here, it will be described as an embodiment.

  In this fume hood system, the air volume control device 113 includes a local exhaust air calculation unit 113-1, a balance air volume calculation unit 113-2, an air volume control unit 111-3, and an air volume control continuation unit 113-4. .

  The air volume control unit 113 is realized by hardware including a processor and a storage device, and a program that realizes various functions in cooperation with the hardware. Specifically, the program is installed in the computer, and the processing operation of the CPU according to the installed program is realized.

  In order to distinguish between the air volume control device 113 in this fume hood system and the air volume control device 113 in the conventional fume hood system shown in FIG. 7, the air volume control device 113 in this fume hood system is denoted by reference numeral 113A. The air volume control device 113 in the fume hood system is denoted by reference numeral 113B.

In the air volume control device 113A of the present embodiment, the local exhaust calculation unit 113-1 sets the wind speed (surface wind speed) of the opening surface of the sash 105 to a predetermined speed (constant) according to the position of the sash 105 detected by the sash sensor 106. The air volume Q _EX of the local exhaust from the fume hood 101 that is maintained at the (wind speed) is calculated.

The balance air volume calculating unit 113-2 is configured to supply the air volume to the chamber 100, the air volume of the general exhaust air from the chamber 100, and the fume hood 101 according to the local exhaust air volume Q _EX calculated by the local exhaust gas calculating section 113-1. Air volume Q _IN1 and Q _IN2 of the supply air from the supply valves 108A and 108B and the general exhaust air volume from the general exhaust valve 111 so that the local exhaust air volume from the air balances with a constant air volume difference (offset air volume). Q _QEX is calculated.

The air volume control unit 111-3 includes the local exhaust air volume Q _EX calculated by the local exhaust gas calculating section 113-1, the supply air volumes Q _IN1 and Q _IN2 calculated by the balance air volume calculating section 113-2, and the general exhaust air. The air volume of the local exhaust valve 103, the air volume of the supply valves 108A and 108B, and the air volume of the general exhaust valve 111 are controlled via the controllers 104, 109A, 109B, and 112 so that the air volume Q _GEX is obtained.

The air volume control unit 111-3 sets the air volumes Q _IN1 and Q _IN2 of the air supplied to the air supply valves 108A and 108B to Q _IN1 = Q when the air volume of the air supply SA (SA1 + SA2) to the chamber 100 is Q _{IN. Calculated as IN} × 0.5 and Q _IN2 = Q _IN × 0.5. That is, Q _IN is proportionally distributed at a ratio of 50% to obtain Q _IN1 and Q _IN2 .

  The air volume control continuation unit 113-4 monitors the operating state of the supply valve 108 (108A, 108B) and determines whether or not a failure has occurred in the supply valve 108 (108A, 108B). Further, when it is determined that the air supply valve 108 (108A, 108B) has failed, the air volume control continuation unit 113-4 uses a predetermined valve as an alternative valve, and the air volume control unit 113-3 controls the air volume (air volume). Continue balance control.

[Example of using a supply valve that has not failed as an alternative valve]
As an operation example of the air volume control continuation unit 113-4, an example in which the air volume balance control is continued using the air supply valve 108 in which no failure has occurred as an alternative valve will be described.

  For example, it is now assumed that the supply valves 108A and 108B are balanced by 25% air volume, the local exhaust valve 103 is balanced by 25% air volume, and the general exhaust valve 111 is balanced by 25% air volume (see FIG. 2A). Here, it is assumed that the supply valve 108A breaks down and is fully closed (see FIG. 2B).

  In this case, the air volume control continuation unit 113-4 determines that a failure has occurred in the air supply valve 108A, and continues the air volume balance control using the air supply valve 108B in which no failure has occurred as an alternative valve. That is, the air supply valve 108B is set to 50% air volume (see FIG. 2C), and the air volume balance is maintained.

[Example of using a general exhaust valve as an alternative valve]
As an operation example of the air volume control continuation unit 113-4, an example in which the air volume balance control is continued using the general exhaust valve 111 as an alternative valve will be described.

  For example, it is now assumed that the supply valves 108A and 108B are balanced by 25% air volume, the local exhaust valve 103 is balanced by 25% air volume, and the general exhaust valve 111 is balanced by 25% air volume (see FIG. 3A). Here, it is assumed that the supply valve 108A breaks down and does not move at that position, the sash 105 is closed in this state, and the local exhaust valve 103 is set to 0% air volume (see FIG. 3B).

In this case, the air volume control continuation unit 113-4 determines that a failure has occurred in the air supply valve 108A, operates the general exhaust valve 111 in place of the air supply valve 108A in which the failure has occurred, and continues the air volume balance control. That is, while the air supply valve 108B is set to 12.5% air volume, the air volume of the general exhaust valve 111 is increased from 25% air volume to 37.5% air volume (see FIG. 3C), thereby maintaining the air volume balance. . Hereinafter, the general exhaust valve 111 that operates instead of the supply valve 108A in which this failure has occurred is also referred to as an alternative valve.

[When there is only one air supply valve]
In the fume hood system shown in FIG. 1, the two supply valves 108 </ b> A and 108 </ b> B are used. However, in the fume hood system (see FIG. 4) having only one supply valve 108, the supply valve 108 is used. If there is a failure, there is no supply valve that has not failed, so the general exhaust valve 111 is used as a substitute valve.

  In this fume hood system, for example, the supply valve 108 is now balanced with 50% air volume, the local exhaust valve 103 is balanced with 25% air volume, and the general exhaust valve 111 is balanced with 25% air volume (see FIG. 5A). . Here, it is assumed that the air supply valve 108 fails and does not move, and the sash 105 is closed in this state, and the local exhaust valve 103 is set to 0% air volume (see FIG. 5B).

  In this case, the air volume control continuation unit 113-4 determines that a failure has occurred in the air supply valve 108, and continues the air volume balance control using the general exhaust valve 111 as an alternative valve. That is, the air volume balance is maintained by increasing the air volume of the air supply valve 108 from 25% air volume to 50% air volume (see FIG. 5C).

  In the first embodiment, the air volume control using the alternative valve is stopped after continuing for a predetermined time. That is, the air volume control using the alternative valve is only temporary and is not performed continuously for a predetermined time or more. This is to prevent the same valve from being continuously used as a substitute valve as much as possible in consideration of the fact that deterioration is accelerated by continuously operating the same valve. In addition, during the air volume control using the alternative valve, the fact is notified. That is, the user or the administrator is notified by voice or the like that either of the supply valves 108A and 108B has failed and the alternative valve is being used.

[Embodiment 2]
In the first embodiment, one fume hood 101 is installed in the chamber 100, but in the second embodiment, a large number of fume hoods 101 are installed in the chamber 100 (see FIG. 6). In this example, it is assumed that 20 fume hoods 101 are installed in the room 100. That is, it is assumed that the system configuration includes 20 local exhaust valves 103, 2 air supply valves 108, and 1 general exhaust valve 111.

  In this case, the supply valves 108A and 108B that perform air volume balance with respect to the opening and closing of the sash 105 of each fume hood 101 increase the number of operations. This shortens the operating life of components such as actuators used to open and close the supply valves 108A and 108B and potentiometers (variable resistors) used to detect the opening positions of the supply valves 108A and 108B. (In the supply valves 108A and 108A, the number of opening and closing is the same because the set air volume is apportioned).

  Therefore, in the second embodiment, the air volume control unit 113-3 is in accordance with the table TB1 indicating the correspondence between each group in which the 20 local exhaust valves 103 are grouped and each of the two air supply valves 108. In accordance with the local exhaust valve 103 that performs local exhaust air volume control from the fume hood 101, a function of performing the air volume control of the air supply valve 108 corresponding to the group to which the local exhaust valve 103 belongs is added.

  In this example, in the table TB1, the supply valve 108A is MAV1, the supply valve 108B is MAV2, and NO. The local exhaust valves 103 from 1 to 10 are set as the first group, and NO. The local exhaust valves 103 of 11 to 20 are set as the second group, the local exhaust valves 103 of the first group are associated with MAV1 (supply valve 108A), and the local exhaust valves 103 of the second group are set to MAV2 (supply valve 108B). ).

  The air volume control unit 113-3 determines NO. According to the relationship associated with this table TB1. When the local exhaust valves 103 of 1 to 10 are opened and closed (the local exhaust air volume control is executed), the air volume control of the air supply valve 108A is performed. When the local exhaust valves 103 of 11 to 20 are opened and closed (execution of local air volume control), the air volume control of the air supply valve 108B is performed. As a result, the number of operations of the supply valves 108A and 108B is reduced, and the operation life of the supply valves 108A and 108B is extended.

  In addition, it replaces with the function mentioned above in addition to the function mentioned above, and the function which selectively switches the air supply valve 108 in charge of the air volume control of the air supply to the chamber 100 in which the fume hood 101 is installed is added. You may do it. With this function, for example, with respect to opening and closing of the local exhaust valve 103 (execution of local air volume control), the supply valves 108A and 108B are alternately opened and closed, or the supply valves 108A and 108B are opened and closed sequentially. Or As a result, the number of operations of the supply valves 108A and 108B is reduced, and the operation life of the supply valves 108A and 108B is extended.

  In the first and second embodiments described above, the description has been given of the example in which the supply valve 108 is two units 108A and 108B, but it goes without saying that the number may be increased. Further, the functions of the air volume control device 113A may be shared by the controllers 104, 109 (109A, 109B), 112, and all the functions of the air volume control device 113A are assigned to the controllers 104, 109 (109A, 109B), 112. You may make it transfer.

[Extension of the embodiment]
The present invention has been described above with reference to the embodiment. However, the present invention is not limited to the above embodiment. Various changes that can be understood by those skilled in the art can be made to the configuration and details of the present invention within the scope of the technical idea of the present invention.

  DESCRIPTION OF SYMBOLS 100 ... Chamber, 101 ... Fume hood, 102A, 102B ... Local exhaust duct, 103 ... Local exhaust valve, 104 ... Controller, 105 ... Sash, 106 ... Sash sensor, 107 (107A, 107B) ... Supply duct, 108 (108A) 108B) ... Supply valve, 109 (109A, 109B) ... Controller, 110 ... General exhaust duct, 111 ... General exhaust valve, 112 ... Controller, 113 (113A) ... Air volume control device, 113-1 ... Local exhaust calculation unit , 113-2 ... balance air volume calculation unit, 113-3 ... air volume control unit, 113-4 ... air volume control continuation unit.

Claims (4)

An air supply valve that adjusts the air volume of the supply air to the room in which the fume hood is installed, a general exhaust valve that adjusts the air volume of the general exhaust from the room, and a local area that adjusts the air volume of the local exhaust from the fume hood In an air volume control device used in a fume hood system equipped with an exhaust valve,
Sash position detecting means for detecting the position of the sash provided to be openable and closable on the front surface of the fume hood;
Local exhaust air volume calculating means for calculating the air volume of the local exhaust from the fume hood so as to maintain the wind speed of the opening surface of the sash at a predetermined speed according to the position of the sash detected by the sash position detecting means;
In accordance with the local exhaust air volume from the fume hood calculated by the local exhaust air volume calculating means, the air supply air volume to the chamber, the general exhaust air volume from the chamber, and the local exhaust air volume from the fume hood are: Balance air volume calculating means for calculating the air volume of the supply air from the supply valve and the air volume of the general exhaust from the general exhaust valve so as to balance with a constant air volume difference;
The local exhaust valve air volume, the air supply valve so that the local exhaust air volume calculated by the local exhaust air volume calculating means, the supply air volume calculated by the balance air volume calculating means, and the general exhaust air volume are obtained. Air volume control means for controlling the air volume of the general exhaust valve and the air volume of the general exhaust valve;
Determining whether a failure in the air supply valve has occurred, if it is determined that the failure to the air supply valve is caused to operate the general exhaust valve in place of the air supply valve in which the failure occurs, the air volume control An air volume control device comprising: air volume control continuation means for continuing the air volume control by the means. In the air volume control device according to claim 1,
The air volume control continuation means includes
An air flow control device, wherein the air flow control by operating the general exhaust valve is continued for a predetermined time and then stopped . An air supply valve that adjusts the air volume of the supply air to the room in which the fume hood is installed, a general exhaust valve that adjusts the air volume of the general exhaust from the room, and a local area that adjusts the air volume of the local exhaust from the fume hood In an air volume control method applied to a fume hood system having an exhaust valve,
A sash position detecting step for detecting the position of a sash provided on the front surface of the fume hood so as to be openable and closable;
A local exhaust air volume calculating step for calculating an air volume of the local exhaust from the fume hood so as to maintain a wind speed of the opening surface of the sash at a predetermined speed according to the position of the sash detected by the sash position detecting step;
According to the local exhaust air volume from the fume hood calculated in the local exhaust air volume calculating step, the air supply air volume to the chamber, the general exhaust air volume from the chamber, and the local exhaust air volume from the fume hood are: A balance air volume calculating step for calculating an air volume of the supply air from the supply valve and an air volume of the general exhaust from the general exhaust valve so as to balance with a constant air volume difference;
The air volume of the local exhaust valve, the air supply valve so that the local exhaust air volume calculated in the local exhaust air volume calculating step, the supply air volume and the general exhaust air volume calculated in the balance air volume calculating step are obtained. And an air volume control step for controlling the air volume of the general exhaust valve;
It is determined whether or not a failure has occurred in the air supply valve. When it is determined that a failure has occurred in the air supply valve, the general exhaust valve is operated instead of the air supply valve in which the failure has occurred, and the air flow control is performed. Air flow control continuation step for continuing air flow control by steps;
An air volume control method comprising: In the air volume control method according to claim 3,
The air volume control continuation step includes:
The general exhaust valve is operated and the air flow control is continued for a predetermined time and then stopped.
An air volume control method characterized by that .

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