JP2018136081A - Air shower device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely suppress the bringing of dust into a clean room. SOLUTION: This is an air shower device that removes dust by blowing clean air from which dust has been removed by a filter on a person or an article in the device by an air jet, and is an static electricity removing device that generates ions that neutralize static electricity. The control unit includes an electrostatic charge measuring device that measures the charging potential of a person or an article in the device, a timer device that sets the operating time of the air jet, and a control unit. The control unit operates the air jet. When the time reaches the operating time set by the timer device and the charging potential measured by the electrostatic charge measuring device becomes equal to or lower than a predetermined potential, the operation of the air jet is stopped. [Selection diagram] Fig. 6

Description

  The present invention relates to an air shower apparatus that removes dust using air pressurized by a fan or the like.

  The air shower device is installed at the entrance or entrance of a clean room or work room for manufacturing semiconductors, precision machinery, etc., or for manufacturing or processing food, or manufacturing pharmaceuticals, etc. Or it is used as an entrance for goods. The air shower device suppresses the inflow and carry-in of dust into the clean room or work room.

  As a function of a general air shower device, air jets are blown out from the air jet nozzles attached to the ceiling and side surfaces to people and items in the air shower device room, and dust attached to the people and items is blown away. . The blown-off dust is sucked from a prefilter (corresponding to an air suction port) provided in the air shower device, pressurized by a fan, and removed through a main filter such as a HEPA filter. Thereafter, the circulating air from which the dust has been removed is blown out again from the air jet nozzle.

  However, when a person or article is charged, there is a problem that it is difficult to remove dust attached to the charged person or article even if an air jet is blown.

  Therefore, there is a case where a static eliminator is installed in the air shower device and static electricity is removed at the same time as an air jet is blown.

  In Patent Document 1, the cleaning chamber 30 including the air shower unit 60 includes a static eliminator 70 that generates ions for neutralizing static electricity in the cleaning chamber, and the static electricity detected by the ion sensor 71 is greater than a predetermined charge amount. In the case of a larger value, it is disclosed that ions having a polarity opposite to the detected polarity are generated (see FIG. 2).

JP 2009-144968 A

  However, since the conventional air shower device with static eliminator does not know the effect of static elimination, there is a problem that the static electricity removal is incomplete and the room or goods are entered into the clean room and dust is again attached and brought into the clean room. there were.

  An object of this invention is to provide the air shower apparatus which suppresses carrying in of the dust into a clean room reliably.

  In the present invention, a static eliminator and an electrostatic charge measuring device are mounted inside an air shower device, the charged potential of a person or an article in the air shower device is measured, and the measurement result is taken into a control unit and monitored.

  An example of an air shower apparatus according to the present invention is an air shower apparatus that removes dust by blowing clean air, from which dust has been removed by a filter, onto a person or an object in the apparatus using an air jet. A static eliminating device that generates ions to be summed, an electrostatic charge measuring device that measures the charging potential of a person or an article in the device, a timer device that sets an operating time of the air jet, and a control unit, The control unit is configured to operate the air jet when the operation time of the air jet reaches the operation time set by the timer device and a charging potential measured by the electrostatic charge measuring device is equal to or lower than a predetermined potential. Is to stop.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to restrict the entrance or receipt of the charged person and goods, and it can suppress reliably the carrying-in of dust to a clean room.

It is a figure which shows an example of the air shower apparatus of the Example of this invention. It is a figure which shows the control structure of the air shower apparatus of an Example. It is a top view which shows the structure of the air shower apparatus of an Example. It is a figure which shows the whole control flow of the air shower apparatus of an Example. It is a figure which shows the control structure of an air jet motor. It is a figure which shows the detailed control flow of an air jet and a static eliminating device.

  Embodiments of the present invention will be described below with reference to FIGS.

1 to 6 show an embodiment of the present invention.
FIG. 1 is a front view showing the configuration of the air shower apparatus. The air shower device 1 includes an air jet fan 2, a main filter 3, a pre-filter 4, an air jet nozzle 5, a control unit 6, a static electricity removing device 8, and an electrostatic charge measuring device 9. These arrangements may not be as shown in FIG.

  The air jet fan 2 sucks air containing dust from the air shower device through the pre-filter 4 and removes the dust through the main filter 3 such as a HEPA filter. An air jet stream 7 is blown onto a person or article to remove dust. The static eliminating device 8 generates ions that neutralize static electricity, and the electrostatic charge measuring device 9 measures the charged potential of a person or an article in the device. The air jet fan 2 and the static electricity removing device 8 are controlled to be turned on and off by the control unit 6.

  FIG. 2 shows a control configuration of the air shower apparatus. The result of the potential measurement by the electrostatic charge measuring device 10 is sent to the control unit 11, and each control such as air jet, interlock, and ON / OFF of the static eliminator is performed. Further, by linking the control unit 11 with the personal computer 12, it becomes possible to manage and monitor the entrance of the air shower device. The result of the electric potential measurement is sent from the control unit 11 to the display device 13, and the electric potential of the person or article in the apparatus is displayed. Although the display 13 is shown in the figure, it may be displayed on the personal computer 12.

  In FIG. 3, the plane block diagram of an air shower apparatus is shown. The air shower device 1 includes a dirty side door 14, a dirty side interlock device 15, a clean side door 16, and a clean side interlock device 17. Here, the dirty side is the side where there is dirty air, for example, outside the clean room. The clean side is a side where there is clean air, for example, in a clean room. The dirty side and clean side doors may be automatic doors or seat shutters. Reference numeral 18 denotes a photoelectric tube switch for operating the air jet, which detects a person entering the room, and the control unit operates the air jet according to the detection signal. The photoelectric tube switch 18 is not limited to the photoelectric tube switch, as long as it is a sensor that can detect the entrance of a room occupant.

  FIG. 4 shows an overall control flow of the air shower apparatus. In FIG. 4, the left column shows the position of a person in the plan view of FIG. 3, the opening / closing of the doors on the dirdy side and the clean side, and the like. The center column shows each step of the operation of the air shower device until entering the clean room through the air shower device. The right column shows the on / off state of the static electricity check, the dirty side interlock, and the clean side interlock corresponding to each operation step.

The air shower device operates in the following steps.
Step 101 is a waiting state before entering the room. At this time, the resident is waiting on the dirty side, and the static electricity check is OFF, the dirty side interlock is OFF, and the clean side interlock is OFF. No static electricity check has been performed, and neither the dirty side door nor the clean side door is locked.
In step 102, the resident opens the dirty side door 14 to enter the air shower. At this time, the static check is OFF, the dirty interlock is OFF, and the clean interlock is ON, and the clean door is locked.
In step 103, the resident enters the air shower apparatus.
In step 104, when the occupant finishes entering the room, the dirty door 14 is closed. At this time, the static electricity check is OFF, the dirty side interlock is OFF, and the clean side interlock is OFF, and the clean side door is unlocked.

In step 105, the phototube switch 18 for operating the air jet is blocked by a person entering the room, and the phototube switch 18 is turned on.
In step 106, when an occupant is detected, the air jet is activated. This air jet operation system may be operated by another means such as a push button switch or a proximity switch other than the phototube switch 18. In addition, it may be operated by closing the door. At this time, the static electricity check is ON, the dirty side interlock is ON, and the clean side interlock is ON, and the static electricity check is started, and the dirty side door and the clean side door are locked. Then, when the air jet is activated, dust of a person or an article is blown off by a high-speed air stream and removed.
In step 107, the electrostatic charge potential is measured by a static electricity check.
If the measured electrostatic potential drops to the set value in step 108, it is determined that the static electricity check is OK. At this time, the static electricity check is OFF, the dirty side interlock is ON, and the clean side interlock is ON, and the static electricity check is terminated.
If the charged potential does not fall to the set value in step 108, the process returns to step 107 and the static electricity amount is further monitored. When the charging potential does not drop to the set value, the air jet continues to operate.
When the charging potential is lowered to the set value, in step 109, the air jet is stopped.

In step 110, a predetermined time has elapsed, and cleanup (sedation) ends. At this time, the static electricity check is OFF, the dirty side interlock is OFF, and the clean side interlock is OFF, and the dirty side door and the clean side door are unlocked.
In step 111, the occupant opens the clean side door 16 to leave the clean side. At this time, the static electricity check is OFF, the dirty side interlock is ON, and the clean side interlock is OFF, and the dirty side is locked.
In step 112, the resident leaves the clean side.
In step 113, the clean side door 16 is closed. At this time, the static electricity check is turned off, the dirty side interlock is turned off, and the clean side interlock is turned off, and the dirty side door is unlocked.
In step 114, the entrant enters the clean room.

In the overall control flow of FIG. 4, control for varying the air jet wind speed according to the amount of static electricity may be performed based on the measurement of the charged potential by the static electricity check in Step 107.
FIG. 5 shows this control configuration diagram. When the charged potential measured by the electrostatic charge measuring device 19 is large, it is difficult to remove dust adhering to a person or an article in the air shower device, so the control unit 20 causes the air jet motor 21 to operate at high speed. On the other hand, when the charging potential is small, dust is easily removed, so the air jet motor 21 is operated at a low speed. If the electrostatic charge measuring device 19 can output in multiple stages, the rotational speed of the air jet motor can be controlled in multiple stages.

Next, a detailed control flow of steps 106 to 109 in the overall control flow will be described with reference to FIG.
In step 201, the air jet and the static eliminator are turned on, and the air jet timer is activated at the same time. Usually, a timer is used to set in advance a time necessary for removing dust from people and articles in the air shower device.
In step 202, it is confirmed whether the operation of the air jet has reached the specified time set by the timer. If it is OK that the specified time has been reached, the process proceeds to the next static electricity check in step 203, and if it has not reached NG, a loop is made until the timer specified time arrival check becomes OK.
In step 203, a static electricity check is performed based on the charged potential measured by the electrostatic charge measuring device to confirm whether the electrostatic potential has reached a specified value. If the electrostatic potential has dropped to the specified value, it is possible to turn off the air jet and the static eliminator in step 204 and proceed to the next operation. When the electrostatic potential is NG higher than the predetermined value, the air jet and the static eliminator are turned on until the static electricity check in step 203 becomes OK, and a loop is performed.

  According to the present example, after the occupant entered the air shower device and the air jet or the static eliminator was activated, the operation of the air jet reached the specified time set by the timer and measured by the electrostatic charge measuring device. Since the operation of the air jet and the static eliminator is stopped when the charged potential drops to a specified value, it is possible to reliably suppress dust from being brought into the clean room and adhering to the dust. Further, since the dirty side interlock and the clean side interlock are operated while the air jet is in operation, it is possible to reliably suppress dust from being brought into the clean room.

  Moreover, based on the charged potential measured by the electrostatic charge measuring device, the air jet is controlled so that the wind speed is increased when the charged potential is high and the wind speed is decreased when the charged potential is low. The removed dust can be removed well.

  Furthermore, since the charging potential measured by the electrostatic charge measuring device is displayed by a display device or the like, the charge amount of a person or an article in the air shower device can be monitored.

DESCRIPTION OF SYMBOLS 1 Air shower apparatus 2 Air jet fan 3 Main filter 4 Pre filter 5 Air jet nozzle 6 Control part 7 Air jet airflow 8 Static electricity removal apparatus 9 Static charge measuring instrument 10 Static charge measuring instrument 11 Control part 12 Personal computer 13 Display 14 Dirty side Door 15 Dirty side interlock device 16 Clean side door 17 Clean side interlock device 18 Photojet tube switch for air jet operation 19 Electrostatic charge measuring device 20 Control unit 21 Air jet motor

Claims (10)

An air shower device that removes dust by blowing clean air from which dust has been removed by a filter onto a person or an object in the device by an air jet,
A static eliminator that generates ions that neutralize static electricity;
An electrostatic charge measuring device that measures the charging potential of people and objects in the device;
A timer device for setting the operating time of the air jet;
A control unit,
When the operation time of the air jet reaches the operation time set by the timer device and the charging potential measured by the electrostatic charge measuring device becomes a predetermined potential or less, the control unit An air shower device that stops operation. In the air shower apparatus according to claim 1,
An air shower apparatus that displays a charging potential measured by the electrostatic charge measuring device. In the air shower apparatus according to claim 1,
The air shower device, wherein the control unit changes a wind speed of the air jet according to a charging potential measured by the electrostatic charge measuring device. In the air shower apparatus of Claim 3,
The controller is configured to increase the wind speed of the air jet when the charging potential measured by the electrostatic charge measuring device is high, and to decrease the wind speed of the air jet when the charging potential is low. Air shower device. In the air shower apparatus according to claim 1,
The control unit detects that a person has entered the apparatus, and operates the air jet and the static eliminator. In the air shower apparatus according to claim 1,
The air shower apparatus characterized in that the control unit operates the dirty side interlock and the clean side interlock at least during the operation of the air jet. In the air shower apparatus according to claim 1,
The air shower device includes a fan and a motor that drives the fan. An air shower device that removes dust by blowing clean air from which dust has been removed by a filter onto a person or an object in the device by an air jet,
A static eliminator that generates ions that neutralize static electricity;
An electrostatic charge measuring device that measures the charging potential of people and objects in the device;
A control unit,
The controller is configured to increase the wind speed of the air jet when the charging potential measured by the electrostatic charge measuring device is high, and to decrease the wind speed of the air jet when the charging potential is low. Air shower device. A main body unit including a fan, a filter, and an air jet nozzle, and an air shower device having a dirty side door and a clean side door provided in the main body unit,
The main body unit includes static electricity removing means, electrostatic charge measuring means, and control means,
The control means includes
When the air jet is blown into the main unit from the air jet nozzle, the dirty side door and the clean side door are closed,
When the electrostatic charge amount in the main body unit measured by the electrostatic charge measuring means is higher than a predetermined value during air jet spraying, the air jet is continuously sprayed, and the electrostatic charge amount is a predetermined value. If it is less, the air shower device stops blowing the air jet. The air shower device according to claim 9,
The air shower apparatus, wherein the control means operates the static electricity removing means during the air jet spraying.

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