JP5222572B2 - Working room - Google Patents

Description

  The present invention relates to a working chamber for unpacking articles and the like.

  In many manufacturing industries such as the food manufacturing and processing industry, an article as a raw material is packed with an exterior material, carried into a factory, and unpacked before use to take out the article as a raw material. At this time, it is not preferable in terms of quality control of the final product that the dust adheres to or mixes with the raw material. In particular, in the food processing industry, it is absolutely necessary to avoid contamination by foreign substances in the manufacturing process. For this reason, the working room in the food processing always releases clean air, and dust is removed by an air shower or the like when a worker or an article enters the room.

  Many techniques are known for the air shower, but there are, for example, a device in which the structure of the air ejection and exhaust is devised (see Patent Document 1) and the charged air shower (see Patent Document 2). Further, as an air shower, there is known a method in which the wall of the work chamber is configured by an air shower as well as being installed at the entrance of the work chamber. In Patent Document 3, an ion wind generated by corona discharge is ejected from a ceiling, a local exhaust device is installed on a corresponding floor surface, and a so-called ion wind air curtain is formed to clean the work chamber. . However, these are facilities that prevent dust from being brought in from the outside when entering the work room.

  In addition to what is brought in from the outside, the dust that adheres to or mixes with the handled articles in the work room may be generated in the work room. When the packing material is a cardboard box or paper, it is often cut or broken and unpacked, but at that time, a piece of paper or paper dust may be generated. As a countermeasure against such dust, there is a so-called clean room method in which air in a working chamber is circulated and dust is discharged together with air. However, even if dust is removed by circulating the air in the working chamber, it is difficult to remove a piece of paper having a certain size. In addition, these pieces of paper and paper dust are easily charged with static electricity, and often adhere to a handling article unpacked in a charged state. When the handling article is non-conductive and easily charged, it is in a state of being easily attached even if a piece of paper or paper dust is not charged. In the case of a fluid food material, the food material is often further packaged and handled in a plastic container or the like, and is easily charged with dust on the surface of the container. In this way, when an unpacked handling article is transported to the next process with a foreign matter such as a piece of paper or paper dust attached thereto, it not only contaminates the handling article but also the environment in the next process. .

A static elimination device is known as a device for removing dust such as paper pieces and paper dust adhering to the surface of the handled article. For example, in Cited Document 4, after unpacking a plastic film, the surface of the plastic film is discharged through an ion generating electrode that generates positive and negative ions by a high voltage and an ion attracting electrode that sucks the generated ions. A static elimination device that removes adhering dust by air jet is disclosed.
JP 2007-139420 A JP 2005-061812 A JP 2002-095998 A Japanese Patent Application Laid-Open No. 08-168697

  As described above, various studies have been made on a method for cleaning the environment of the work room and an apparatus and a method for removing dust from articles taken out by unpacking work or the like in the work room. However, it is not enough to manage individual work rooms and final products in order to prevent dust from getting into products, semi-finished products, raw materials, etc., as a whole manufacturing process as in the food processing industry. . When handling articles such as raw materials and semi-finished products are sent to the next process after finishing each work process, they must be kept free of dust. In particular, care should be taken in removing dust from articles handled in an unpacking work room for raw materials that generate paper dust or paper dust.

  An object of the present invention is to provide a work chamber that can be carried out without adhering dust such as a piece of paper to a handled article that has been handled such as unpacking, based on the above-described problems.

In order to solve the above problems, the present inventors have completed the following invention.
The present invention provides a working chamber that discharges clean air from the ceiling and exhausts air from the floor to keep indoor air clean, and a transfer device that carries out a handled article handled in the working chamber to the outside of the working chamber. An electrostatic dust removing device for removing static electricity from the surface of the handling article on the transport device and removing the dust attached to the handling article. It is a working room.

The inside of the working chamber is kept at a reduced pressure from the outside, and the electrostatic dust remover includes an ion generator based on corona discharge , an air outlet for ejecting clean air, and an exhaust gas larger than the amount of air supplied from the air outlet. And an exhaust port having a quantity .

  In a preferred embodiment of the present invention, the electrostatic dust remover further includes a humidifier.

  A preferred embodiment of the present invention is the working chamber including an inner wall surface having antistatic performance.

  In a preferred aspect of the present invention, the indoor air exhausted from the floor of the working chamber is purified and circulated and discharged from the ceiling.

  In a preferred aspect of the present invention, a part of the circulated air is exhausted outside the work chamber.

  In a preferred aspect of the present invention, the work chamber is characterized in that the transfer device can continuously carry out the handling article.

  ADVANTAGE OF THE INVENTION According to this invention, the working chamber which can carry out without attaching dust, such as a paper piece, to the handling article which finished handling work, such as unpacking, can be provided.

  The best mode for carrying out the present invention will be described with reference to the drawings as necessary. Note that it is easy for a person skilled in the art to make other embodiments by changing or correcting the present invention within the scope of the claims, and these changes and modifications are included in the scope of the claims. The following description is an example of a preferred embodiment of the present invention, and does not limit the scope of the claims.

  The working chamber of the present invention has a working chamber that discharges clean air from the ceiling and exhausts air from the floor to keep the indoor air clean, and a transfer device that carries out the handled articles handled in the chamber to the outside of the working chamber. And an electrostatic dust removing device for removing static electricity from the surface of the handling article on the transport device and removing dust adhering to the handling article.

  The embodiment of the working chamber of the present invention will be described with reference to the illustration of FIG. As shown in FIG. 1, the working chamber of this embodiment includes an air supply chamber 15 that discharges clean air to the ceiling, and an exhaust chamber 18 that sucks air containing dust on the floor to keep the indoor air clean. Has a working chamber 2. A high-performance filter 16 is installed at the air discharge port of the air supply chamber 15, and the type of fill, the cleaning frequency, and the replacement frequency are determined in accordance with the cleanliness required for the working chamber 2. Also, the speed of air release from the air discharge port of this filter is high enough to press the dust generated during work against the floor surface.If it is too slow, it will not be able to sufficiently push the dust into the floor surface. Care should be taken because it will be lifted. Since the specific release speed varies depending on the type and size of dust, the strength of charging, the humidity in the room, and the like, it is preferable to obtain the optimum place by experimentation or the like. Further, the clean air is preferably discharged uniformly from the entire ceiling, and the discharge of air containing dust from the floor surface is preferably discharged from the entire floor surface.

  The air supplied to the air supply chamber 15 is preferably clean. Further, it is preferable that the air exhausted into the exhaust chamber 18 is purified and discharged. Considering the balance of the air in the working chamber 2, the amount of air supplied from the supply chamber 15 and the amount of air exhausted to the exhaust chamber 18 are substantially the same, so the air exhausted to the exhaust chamber 18 is purified. There is a method of circulating and supplying to the air supply chamber 15. In FIG. 1, such an air circulation system is adopted. In this case, the air supply blower to the air supply chamber 15 and the exhaust blower from the exhaust chamber 18 can serve as one blower 12.

  The air in the work chamber 2 is exhausted from an opening floor 17 such as punching metal, grating, or lattice top floor disposed on the floor surface of the work chamber 2. It is preferable that the open floor 18 is opened as evenly as possible over the entire floor surface so that the air in the working chamber 2 is uniformly sucked into the exhaust chamber 18 below the floor. For this reason, the blower 12 is connected to the exhaust chamber 18, and the air in the exhaust chamber 18 is preferably exhausted by the blower 12 so that the inside of the work chamber 2 is more decompressed than the outside of the chamber. In a food processing process or the like, the room in which the work chamber 2 is installed is cleaned, so there is no problem in that air enters the work chamber 2 from the room in which the work chamber 2 is installed. However, when dust generation work such as unpacking work is performed in the work chamber 2, dust is scattered in the work chamber. Therefore, in order to guide all of the scattered dust to the exhaust chamber under the floor, It is preferable to reduce the pressure from the outside so that air does not leak into the outside room. As a specific structure for keeping the inside of the working chamber 2 at a reduced pressure, an exhaust port 13 is provided in the middle of the circulation duct 10 for circulating air from the blower 12 to the air supply chamber 15, and from here by adjusting the valve or the like. A part of the circulating air may be discharged.

  Note that the air exhausted to the exhaust chamber 18 includes dust such as paper pieces and paper dust generated during operations such as unpacking. Therefore, a filter 11 is provided in front of the intake line of the blower 12 so that the blower 12 removes the air containing these before sucking. By doing so, there is an advantage that the blower 12 is less likely to break down, clean air without dust is supplied to the air supply chamber 15, and the load on the high-performance filter 16 is reduced. Further, since the air discharged from the exhaust port 13 downstream of the blower 12 is also clean, the exhausted room outside the working chamber 2 is not contaminated. The filter 11 may be a commonly used filter such as a glass wool filter, a mesh filter, a sintered metal filter, or a bag filter. However, considering the cost and replacement frequency, the filter 11 having a higher dust removal performance is selected. There is no need. A cyclone, a centrifugal dust remover, a collision plate dust remover, a natural fall dust remover, or the like may be used in combination.

  In the working chamber 1 of this embodiment, the worker 5 in the working chamber 2 unpacks the handling articles 4 packed with raw materials, for example, and takes out the handling articles 4 one by one. In the work chamber 1, a transport device 7 for carrying out the handled article 4 that has been handled such as unpacking work is installed, and is placed thereon. The transfer device 7 is configured to carry out the handled article 4 from the inside of the work chamber 2 to the outside. The conveying device 7 may be any device as long as it is a commonly used conveying device, such as a belt conveyor, a roller conveyor, an escalator, a slide-type gravity transfer device, a forklift, a carriage, a truck, an elevator, etc. But you can. As the transport device 7, FIG. 1 shows a roller conveyor using gravity. It is preferable that the transfer device 7 can continuously carry out the handled article 4 because the working chamber can be effectively used. The transport device 7 may determine its form, structure, installation position, and the like according to the position of the worker 5, the form of the handled article 4, the handling method, the relationship with the next process after unloading, and the like. In the form shown in FIG. 1, the handled article 4 carried out by the conveying device 7 is loaded on a handled article conveying container 20 and further conveyed to the next manufacturing process or the like.

  The working chamber 1 of this embodiment includes an electrostatic dust remover 3 that removes the surface of the handling article 4 on the conveyance path of the conveyance device 7. The electrostatic dust remover 3 is installed so as to cover a part of the conveyance path of the conveyance device 7, and includes an ion generator 8 by corona discharge and a humidifier 9 in an upper part through which the handled article 4 passes. Furthermore, there is an air blowing port in the upper part of the electrostatic dust removing device 3, clean air is introduced and ejected by the duct 10, and there is an exhaust port in the lower part of the electrostatic dust removing device 3. Is exhausted to the exhaust chamber 18. In the form of FIG. 1, the center of the electrostatic dust removing device 3 passes through the conveyance path of the conveyance device 7 for conveying the handled article 4, and the handled article 4 is continuously conveyed from left to right. It is a mechanism to be done. It is preferable that the residence time of the handled article 4 in the electrostatic dust removing device 3 can be adjusted in consideration of the electrostatic dust removing performance of the handled article 4. In addition, the installation method of the electrostatic dust remover 3 can be variously modified in addition to the method shown in FIG.

  The ion generator 8 shown in FIG. 1 will be briefly described with reference to FIG. FIG. 2 conceptually shows the ion generator 8. The ion generator 8 is connected to a high voltage generator 21 that generates a high voltage, and is connected to the high voltage generator 21, and a high voltage is applied thereto. A discharge electrode 22 and a ground electrode 23 as a counter electrode of the discharge electrode 22 are provided. The high voltage generator 21 is connected to a power source 24.

  The discharge electrode 22 and the ground electrode 23 are opposed to each other with an appropriate distance. When a high voltage is applied between the two electrodes, corona discharge occurs between the two electrodes. Due to this corona discharge, a part of the surrounding air is ionized and ionized. A flow of clean air supplied from the duct 10 is formed around the electrode, and a part of the ionized air flows out to the lower part of the electrostatic dust removing device 3 together with the air flow. In the ionization of air, it is preferable to use clean air without dust. If there is an impurity such as dust, the electric charge moves to the dust, reducing not only the amount of ions generated, but also the charged dust adheres to the discharge electrode and the ground electrode. If dust adheres to the electrode, the discharge efficiency, that is, the ion generation efficiency is lowered, which is not preferable.

  In the example of FIG. 2, the ionized positive ion 26 flows out together with the air flow without being supplemented by the ground electrode 23, and the article to be discharged 27 in the electrostatic dust removing apparatus 3 (in the embodiment shown in FIG. Equivalent). The surface of the article 27 to be neutralized or dust such as a piece of paper adhering to the surface is charged. When the positive ions 26 approach, the charges are supplemented to neutralize the charge, and are also discharged and neutralized. . When the surface of the article to be neutralized 27 and the adhering dust are neutralized and the electrostatic attractive force disappears, the dust easily peels off from the surface of the article to be neutralized 27 and falls off. As shown in FIG. 1, an airflow sucked from the exhaust port at the lower part of the electrostatic dust remover 3 is formed around the handled article 4 (charged article 27), so that it is neutralized together with the dropped dust. In addition, a part of the dust adhering to the surface of the article 27 to be discharged is also easily peeled off by the air flow, and is guided to the exhaust chamber 18 from the exhaust port together with the air flow.

As the ion generator 9, a commercially available product (for example, a static eliminator (Model ND503T) manufactured by Kasuga Electric Co., Ltd.) can be used.
Ion generation method: DC corona discharge type discharge electrode: Low dust generation special alloy atmosphere Air pressure: 0.02-0.15 MPa
Air flow rate: 45 to 105 L / min
Power supply used: 100V (AC power supply)
Power consumption: 4VA
Ozone generation amount: 0.02 ppm or less Usage environment: 0 to 40 ° C., 80% RH or less Mass: 1.5 kg
A humidifier 9 is provided in the vicinity of the ion generator 8 of the electrostatic dust remover 3. By humidifying the clean air released from the duct 10 by the humidifier 9, the ion generation efficiency of the ion generator 8 and the stability of the generated ions can be improved. When gaseous water molecules are present in the ion generating portion of the ion generator 8, the water molecules are easily ionized to become ions and become relatively stable ions, so that the ion generation efficiency can be improved. Further, by humidifying the air in the electrostatic dust remover 3, the surface of the handled article 4 that has been conveyed and the dust such as adhering paper pieces are humidified to weaken the charging property, Dust separation can be promoted. However, when the vicinity of the ion generator 8 is humidified, care must be taken not to cause condensation on the electrode of the ion generator 8 or in the vicinity thereof. Since a high voltage is applied to the electrode of the ion generator 8, if conductive moisture adheres, unexpected leakage or discharge occurs, causing not only a reduction in the efficiency of the ion generator but also a failure or accident.

  The clean air ejected from the upper part of the electrostatic dust removing device 3 is preferably air cleaned by the high-performance filter 16. The balance between the air supply and the exhaust in the electrostatic dust removing device 3 is preferably such that the exhaust amount is larger than the air supply amount from the duct 10. In this way, all the air in the electrostatic dust remover 3 is exhausted and does not leak out of the electrostatic dust remover 3. With such a structure, a small amount of ozone may be generated by corona discharge in the electrostatic dust remover 3, but all of this can be recovered in the exhaust chamber 18. Note that since the ozone collected in the exhaust chamber 18 is small, it may be decomposed spontaneously. However, in order to eliminate this reliably, the filter 11 has an absorbent or reducing reagent for absorbing ozone such as activated carbon or zeolite. It is preferable to provide an ozonolysis agent containing

  In the working chamber 1 of this embodiment, the inner wall surface 19 of the working chamber 2 has antistatic performance. When the inner wall surface 19 of the working chamber 2 is charged, dust in the working chamber 2 is likely to adhere to the inner wall surface 19 and is difficult to be discharged from the opening floor 17 together with the exhaust air. Then, dust adhering due to a change in humidity or vibration in the working chamber 2, a change in the amount of air discharged from the ceiling, etc. may be detached again and rise to the air and adhere to the handling article 4. In addition, if the inner wall surface 19 of the working chamber 2 is charged, the charge is transferred to the dust in the air to promote the charging of the dust. From this point also, there is a possibility that the dust adheres to the handled article 4. Increase. When the inner wall surface 19 of the working chamber 2 has antistatic performance, it is possible to prevent such adhesion of dust to the inner wall surface 19 and charging of dust.

  The inner wall surface having antistatic performance may be any form of inner wall surface, but may be made of, for example, a grounded conductive material. Specific examples of the inner wall surface 19 include a metal plate, a plate containing a conductive material such as metal and carbon, and wood containing some moisture. However, a plastic plate, a plate having a non-conductive coating on the surface, a plate whose surface is covered with a material that is easily charged, such as a vinyl wallpaper or a plastic film, are not preferable. In the case of such a wall material having a surface that is easily charged, the surface may be subjected to an antistatic treatment with an antistatic agent or an antistatic film to form an antistatic treatment wall. The material having antistatic performance is in contact with air, not only on the inner wall surface 19 but also on the ceiling, the inner wall of the air supply chamber 15, the floor, the exhaust chamber 18, the surface of the transfer device 7, the wall surface of the electrostatic dust removal device 3, etc. It is preferable to use it for the part. Furthermore, adjusting the air in the working chamber 2 to an appropriate humidity with a humidifier or the like is also effective for preventing charging of the wall surface and dust.

Conceptual diagram of the working room of the present invention Conceptual diagram of ion generator

Explanation of symbols

1: Work chamber 2: Work chamber 3: Electrostatic dust removing device 4: Handling article 5: Worker 6: Packaged handling article 7: Transport device 8: Ion generator 9: Humidifier 10: Circulation duct 11: Filter 12 : Blower 13: Exhaust port 14: Valve 15: Air supply chamber 16: High performance filter 17: Open floor 18: Exhaust chamber 19: Inner wall surface 20: Handling article transport container 21: High pressure generator 22: Discharge electrode 23: Ground electrode 24: Power supply 25: Negative charge 26: Positive charge 27: Charged article

Claims (6)

A working chamber that releases clean air from the ceiling and exhausts from the floor to keep the indoor air clean;
A transfer device for carrying out a handled article handled in the working chamber out of the working chamber;
An electrostatic dust removing device for removing static electricity from the surface of the handling article and / or the dust attached to the surface of the handling article on the transport device, and removing the dust attached to the handling article ;
The inside of the working chamber is kept under reduced pressure from the outside,
The electrostatic dust removing device includes an ion generator based on corona discharge, an air outlet that ejects clean air, and an exhaust outlet that has an exhaust amount larger than the amount of air supplied from the air outlet. Working room. The working chamber according to claim 1 , wherein the electrostatic dust remover further includes a humidifier. Working chamber according to claim 1 or 2, characterized in that it comprises an inner wall surface having antistatic properties. Said air chamber which is evacuated from the floor of the working chamber, while being cleaned, the working chamber according to any one of claims 1 to 3, characterized in that it is released from the ceiling circulated. The working chamber according to claim 4 , wherein a part of the circulated air is discharged outside the working chamber. The conveying device, the working chamber according to any one of claims 1 to 5, characterized in that it continuously unloading the handling article.

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