JP3227619U - Electrostatic precipitator for face shield - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a face shield capable of collecting fine particles suspended in the air between an internal face and an internal face by the action of electrostatic precipitating.
SOLUTION: An electrostatic precipitator is provided inside a face shield 2 covering a face to have an air purifying action. Specifically, a two-stage electrostatic precipitator is configured by providing a corona emission electrode 3 and a dust collecting electrode having a function of applying a voltage between opposed flat plate electrodes to collect charged fine particles. The device is used. Alternatively, a one-stage electrostatic precipitator composed of a corona emission electrode and a net-like ground electrode 8 facing each other at a distance of 2 mm or more from the tip thereof is provided inside a face shield covering the face.
[Selection diagram] Fig. 2

Description

Devised an electrostatic precipitator installed on the inner surface of the face shield to purify the air inside the face shield, which is often used for medical purposes to prevent infection.

A face shield that covers the face is used to prevent virus infection. This face shield blocks droplets scattered by coughing. However, the air inside the face shield cannot be cleaned. The mask is used to prevent infection because it reduces the spread of droplets scattered by coughing and can filter the inspiration when breathing, but it cannot completely prevent the leakage of air from around the mask. , The filtration of fine particles in exhaled breath may be insufficient. The electrostatic precipitator charges suspended fine particles by corona discharge and exerts electrostatic force to collect dust. It is widely used for industrial purposes, but it has a risk of electric shock because it uses a high voltage. There are few examples of being used in contact with the human body.

Japanese Patent Application Laid-Open No. 08-112549 "Corona discharge unit using carbon fiber as a discharge electrode and electrostatic precipitator, gas purifier, and static eliminator using the same" includes a corona discharge unit that has high performance and does not deteriorate in time. For the purpose of providing an electrostatic precipitator, a gas purifier, and a static eliminator using this, carbon fiber is used for the corona discharge electrode, and this is insulated and opposed to the counter electrode to form a corona electrode system, and both electrodes. A corona discharge unit that generates corona discharge from the tip of the carbon fiber by combining with a high-pressure power supply that applies a high voltage is constructed, and this discharge unit is used to charge particulate contaminants, and this charge is downstream of it. A method of constructing an electric dust collector by providing a dust collecting unit for collecting fine particles is described.

Mizuno, A, Yasuda, H. et al. "Damages of Biological Components in Bacteria and Bacteriophages Exposed to Atmospheric Non-thermal Plasma, Plasma for Bio- Decontamination, Medicine and Food Security (NATO Science for Peace and Security Series A: Chemistry and Biology)", Springer, pp. 79-92, 2012 show that the use of electrostatic precipitators by corona discharge significantly improves the effect of collecting bacteria floating in the atmosphere. M Abdel-Salam, M Nakano, A Mizuno, "Corona-induced pressures, potentials, fields and currants in electrostatic precipitator cofigurations". Phys. D: Apple. Phys. , 40, 2007, pp. In 1919-926, analysis of the atmospheric pressure difference caused by the movement of ions generated by the corona discharge is performed. Due to this pressure difference, ionic wind is generated along with the corona discharge.

Face shields that cover the face are used in medical settings to prevent infection. This face shield has the effect of blocking the arrival of droplets scattered from the human body during coughing and conversation. However, since it does not have the function of purifying the air between the face and the inside of the face shield, it is necessary to introduce clean air from the outside into the cover via a tube or the like in order to obtain clean intake air. .. Masks are also used to prevent infection, but since it is difficult to completely prevent air leakage from around the mask, the effect of preventing the invasion of fine particles such as viruses into the inhalation is limited. ..

An electrostatic precipitator is installed inside the face shield in order to purify the air in the space inside the face shield and supply clean intake air without introducing clean air from the outside.

Inside the face shield, an electrode for generating corona discharge is provided, and a dust collecting electrode having a function of applying a voltage between opposed flat plate electrodes to collect charged fine particles is provided, so-called two-stage electric collection. Configure the dust collector. Alternatively, the electrostatic precipitator is provided by providing a net-like ground electrode at a distance of 2 mm or more from the tip of the electrode for generating corona discharge.

The configuration in which the two-stage electrostatic precipitator is provided inside the face shield (2) covering the face (1) is shown. The electrode for generating corona discharge may have a shape such as a sharp needle or a thin wire in which an electric field is concentrated. In particular, it is preferable to use fine carbon fiber or stainless steel fiber. The corona discharge generating electrode (3) is provided in the face shield, and a dust collecting electrode (4) composed of parallel flat plate electrodes is provided. When the dust collection electrode is installed so that the end of the ground electrode (5) of the dust collection electrode is at a position separated from the tip of the corona discharge generation electrode by 2 mm or more, the ground side electrode of the dust collection electrode is for corona generation. Since it also serves as a ground electrode for the electrode, it is effective for miniaturization. A DC high voltage is applied to the high voltage electrode (6) of the dust collecting electrode to form an electric field between the dust collecting electrodes to collect fine particles charged by corona discharge. When a corona discharge is generated, ions are generated, and when the ions move from the corona discharge electrode to the ground electrode, an ion wind is generated. The air flow generated by this, that is, the ionic wind, moves the air inside the face shield without inserting a fan, so the whole can be cleaned. A small fan may be used to agitate the internal air more uniformly. Further, the polarity of the corona discharge is preferably positive from the viewpoint of reducing the amount of ozone generated. In addition, it is desirable to apply activated carbon powder or an ozone decomposition catalyst (7) to the dust collecting electrode or the inner surface of the face shield to decompose the generated ozone. A corona discharge electrode (3) is provided inside the face shield (2), a gap of 2 mm or more is provided from the tip thereof, and a ground electrode (8) made of a mesh of conductors is provided. The corona discharge charges the fine particles floating in the air inside the face shield, and the electric field collects the dust. The polarity of the corona discharge is preferably positive, which is known to reduce ozone generation. If the odor of ozone becomes anxious at the level of 0.1 ppm, apply activated carbon powder or ozone decomposition catalyst powder (7) to the reticulated ground electrode, and place activated carbon or ozone decomposition touch inside the face shield. Decomposes ozone. In addition, since the face shield is disposable, the electrostatic precipitator installed inside the face shield will be removable and will be attached to a new face shield with a clip when it is replaced.

In the example in which the two-stage electrostatic precipitator shown in FIG. 1 is incorporated, a brush in which 100 stainless fibers having a length of 5 mm are bundled is used as a discharge electrode. Further, two flat plate ground electrodes having a width of 30 mm and a height of 50 mm and one flat plate high voltage electrode having a width of 20 mm and a height of 40 mm are arranged with an interval of 5 mm to form a dust collecting electrode by a parallel flat plate. This is placed at a horizontal distance of 3 mm (horizontal distance from the end of the ground flat plate electrode) from the tip of the corona discharge electrode, and a DC voltage of positive + 3 kV is applied to the corona discharge electrode to generate a corona discharge. Further, the same high voltage of + 3 kV is applied to the flat plate high voltage electrode arranged at the center of the dust collecting electrode. In addition, activated carbon powder is applied to the outside of the dust collecting electrode to reduce the generated ozone. An output resistor of 1 GΩ is inserted in the power supply to prevent overcurrent from flowing even if a flash occurs between the corona discharge electrode and the ground electrode. It is desirable to use an output resistance value of 10 kΩ to 1 GΩ. The corona emission electrode and the parallel flat plate dust collection electrode are provided inside two sets of covers symmetrically on the left and right. Further, these electrodes and the power supply have a structure that can be easily attached and detached when the face shield is replaced.

In the one-stage electrostatic precipitator shown in FIG. 2, a corona discharge electrode composed of a bundle of stainless fibers is provided inside the face shield, and a grounded net-like electrode is provided at a distance of 10 mm from the tip of the discharge electrode. A high voltage of 3 kV positive is applied to the corona emission electrode. Activated carbon powder is applied to the surface of the net electrode to reduce ozone generated by corona discharge. An output resistor of 1 GΩ is inserted in the power supply to prevent overcurrent from flowing even if a flash occurs between the corona discharge electrode and the ground electrode. Further, these electrodes and the power supply have a structure that can be easily attached and detached when the face shield is replaced.

The present invention was carried out using the two-stage electrostatic precipitator shown in FIG. 1 and the one-stage electrostatic precipitator shown in FIG. The end of the face shield was brought into close contact with the face, and the number concentration of fine particles floating in the air was measured with a particle counter. As an example of the measurement result, when the count number of 0.5 μm fine particles suspended in the air is 12,000 (in 2.8 L of air), a two-stage electrostatic precipitator and a one-stage electrostatic precipitator In each of the devices, the count number was around 120 5 minutes after the voltage was applied, and a 99% removal effect was obtained. It was also suggested that the cleanliness of the air inside the cover can be improved by making the gaps on the top, bottom, left and right of the cover as small as possible. It was also suggested that by using this face shield from above even when wearing a mask, the air leaking from around the mask is normalized, and the effect of infection prevention can be enhanced.

Expected to prevent infection by airborne particles such as viruses.

1. 1. Face 2. Plastic face shield 3. Corona discharge electrode 4. Electric field dust collector 5. Grounding electrode for electric field dust collector 6. Electric field dust collector High voltage electrode 7. Activated carbon powder or ozonolysis catalyst 8. Reticulated ground electrode of conductor 9. Battery 10. High voltage power supply 11. Output resistance

Claims (2)

A two-stage electrostatic precipitator provided with a corona emission electrode inside the face shield that covers the face used to prevent infections such as viruses, and a dust collection electrode composed of parallel flat plate electrodes. A device that purifies the air inside the face shield A face shield characterized in that a sharp discharge electrode that generates corona discharge and a mesh-like ground electrode that faces each other at a distance of 2 mm or more from the tip thereof are provided between the face.

Images