JP-7854600-B2 - Particulate sampling apparatus and particulate sampling method

JP7854600B2JP 7854600 B2JP7854600 B2JP 7854600B2JP-7854600-B2

Inventors

成畑晃希

Assignees

パナソニックＩＰマネジメント株式会社

Dates

Publication Date: 20260507
Application Date: 20220412
Priority Date: 20210426

Claims (16)

A first electrode having a cylindrical shape, a first opening located at the first end of the cylinder in the axial direction, and a second opening located at the second end of the cylinder in the axial direction, A second electrode extending in the axial direction and positioned within the first electrode at a distance from the inner surface of the first electrode, A third electrode extending in the axial direction and positioned within the first electrode at a distance from the inner surface, wherein the third electrode is thicker than the second electrode . A supply unit that supplies liquid into the first electrode and stores the liquid in a part of the inner surface in the direction of the axis of the first electrode, A voltage application unit that applies a first voltage between the first electrode and the second electrode, and a second voltage between the first electrode and the third electrode, A drive unit that rotates the first electrode about a rotation axis that extends in the axial direction and passes through the first electrode, The system includes a recovery unit for recovering the stored liquid, The positions of the third electrode and the second electrode are different in the axial direction. A particulate sampling device.
The third electrode is arranged in the axial direction alongside the second electrode, The particulate sampling apparatus according to claim 1.
Within the first electrode, the third electrode is longer than the second electrode. The particulate sampling apparatus according to claim 1 or 2.
Within the first electrode, the second electrode is positioned between the first opening and the first surface, and is not positioned between the first surface and the second opening. Within the first electrode, the third electrode is not positioned between the first opening and the first surface, but is positioned between the first surface and the second opening. The second electrode and the third electrode are in direct contact on the first surface. The distance between the first surface and the first opening is smaller than the distance between the first surface and the second opening. The first surface and the axial direction are perpendicular. The particulate sampling apparatus according to claim 3.
At least a portion of the third electrode is formed integrally with the second electrode. A particulate sampling apparatus according to any one of claims 1 to 4.
The third electrode comprises a core member extending in the axial direction and a covering member that is conductive and covers the core member. A particulate sampling apparatus according to any one of claims 1 to 5.
The core member is formed integrally with the second electrode such that the second electrode and the core member are continuous in the axial direction. The particulate sampling apparatus according to claim 6.
It is further equipped with a control unit and wind speed sensor, The control unit determines that the measured value of the wind speed sensor indicates the wind speed of the gas in the first electrode. A particulate sampling apparatus according to any one of claims 1 to 7.
The control unit calculates the flow rate of the gas based on the measurement result of the wind speed sensor and outputs the flow rate . The particulate sampling apparatus according to claim 8.
The system further includes an air concentration sensor, and the control unit determines that the measured value of the air concentration sensor indicates the concentration of fine particles in the gas within the first electrode. The control unit controls the voltage application unit and the drive unit based on the measurement results of the air concentration sensor. The particulate sampling apparatus according to claim 9.
The system further includes a liquid concentration sensor for measuring the concentration of fine particles in the stored liquid, The control unit stops applying voltage by the voltage application unit if the concentration measured by the liquid concentration sensor is higher than a predetermined concentration. The particulate sampling apparatus according to claim 9 or 10.
The system further comprises an ammeter for measuring the value of a first current flowing between the first electrode and the second electrode, the value of a second current flowing between the first electrode and the third electrode, or the value of a third current based on the first current and the second current. The control unit, when the current value measured by the ammeter is greater than a predetermined value, causes the supply unit to replenish the liquid in the first electrode. A particulate sampling apparatus according to any one of claims 9 to 11.
The inner surface of the first electrode is subjected to a hydrophilic treatment. A particulate sampling apparatus according to any one of claims 1 to 12.
A adhesion-suppressing member is attached to the inner surface of the first electrode to suppress the adhesion of fine particles. A particulate sampling apparatus according to any one of claims 1 to 13.
The liquid is a liquid for analyzing fine particles in the liquid. A particulate sampling apparatus according to any one of claims 1 to 14.
A method for sampling fine particles for a fine particle sampling device, The aforementioned particulate sampling device is A first electrode having a cylindrical shape, a first opening located at the first end of the cylinder in the axial direction, and a second opening located at the second end of the cylinder in the axial direction, A second electrode extending in the axial direction and positioned within the first electrode at a distance from the inner surface of the first electrode, The electrode comprises a third electrode that extends in the axial direction and is positioned within the first electrode at a distance from the inner surface, The third electrode is thicker than the second electrode, and the positions of the third electrode and the second electrode differ in the axial direction. The aforementioned fine particle sampling method is A liquid is supplied into the first electrode, and the liquid is stored in a portion of the inner surface in the direction of the axis of the first electrode. A first voltage is applied between the first electrode and the second electrode, and a second voltage is applied between the first electrode and the third electrode. The first electrode is rotated about a rotation axis that extends in the axial direction and passes through the first electrode, This includes recovering the stored liquid, A method for sampling fine particles.

Description

This disclosure relates to a particulate sampling apparatus and a particulate sampling method for sampling particulate matter. Conventionally, devices and methods for sampling fine particles in a gas are known that utilize the inertia and centrifugal force of fine particles (see, for example, Patent Documents 1, 2, and 3). Patent Document 1 discloses a method for capturing airborne microorganisms on a membrane filter by sucking air through a membrane filter. Patent Document 2 discloses an airborne microorganism sampler that collects airborne bacteria by causing them to adhere to a culture medium by colliding air sucked in from a suction unit with the culture medium. Patent Document 3 discloses a device that separates and collects a target object from the air using centrifugal force generated by the swirling of sucked air. Japanese Patent Publication No. 2008-161143Japanese Patent Publication No. 2009-11265Japanese Patent Publication No. 2012-52866 However, with the conventional configuration described above, fine particles such as aerosols separated from the aspirated air often accumulate in a dry state, requiring further steps for analysis, such as extraction into a solution. If the sampled fine particles are biological, they cannot be collected while maintaining their activity. Even with systems designed to recover particles in a solution to address these issues, obtaining high concentrations requires a large amount of solution, which takes a lot of time, and the suction process generates significant pressure loss and noise. In addition, the collection performance is largely dependent on factors such as the shape and size of the device, the suction speed, and the size of the target aerosol, resulting in challenges in efficient collection. When using electrostatic sampling, it is usually possible to efficiently sample fine particles by charging a larger number of target particles through discharge. However, there is a problem in that active substances such as ozone are generated during this discharge. These active substances can oxidize the target particles, potentially adversely affecting the inspection of the particles after sampling. This disclosure has been made in view of the above-mentioned conventional problems, and provides a particulate sampling device and a particulate sampling method that can efficiently sample particulate matter while suppressing the generation of active substances. A particulate sampling apparatus according to one aspect of the present disclosure comprises a cylindrical first electrode having a first opening located at a first end in the axial direction of the cylinder and a second opening located at a second end in the axial direction of the cylinder; a second electrode extending in the axial direction and disposed within the first electrode at a distance from the inner surface of the first electrode; a third electrode extending in the axial direction and disposed within the first electrode at a distance from the inner surface of the first electrode; a supply unit in which the third electrode is thicker than the second electrode and supplies liquid into the first electrode and stores the liquid in a part of the inner surface of the first electrode in a direction around the axial center; a voltage application unit in which a first voltage is applied between the first electrode and the second electrode and a second voltage is applied between the first electrode and the third electrode; a drive unit in which the first electrode is rotated around a rotation axis extending in the axial direction and passing through the first electrode; and a recovery unit in which the stored liquid is recovered , wherein the third electrode is thicker than the second electrode and the positions of the third electrode and the second electrode are different in the axial direction . A particulate sampling method according to one aspect of the present disclosure is a particulate sampling method for a particulate sampling apparatus, the particulate sampling apparatus comprising: a first electrode which is cylindrical and has a first opening located at a first end in the axial direction of the cylinder and a second opening located at a second end in the axial direction of the cylinder; a second electrode which extends in the axial direction and is disposed within the first electrode at a distance from the inner surface of the first electrode; and a third electrode which extends in the axial direction and is disposed within the first electrode at a distance from the inner surface of the first electrode, wherein the third electrode is thicker than the second electrode, and the positions of the third electrode and the second electrode are different in the axial direction; the particulate sampling method comprises supplying liquid into the first electrode, storing the liquid in a part of the inner surface of the first electrode in a direction about the axial direction; applying a first voltage between the f