Gas particle counter

Abstract

The present invention relates to a particle counter for gas, comprising: a casing equipped with an inlet port and an outlet port; a main line located inside the casing, with both ends connected to the inlet port and the outlet port of the casing, respectively, through which sample gas is introduced and discharged; a particle sensor connected to the main line to analyze particles of the sample gas flowing through the main line; a mass flow rate regulator connected to the main line to be positioned between the particle sensor and the inlet end of the main line, which regulates the flow rate of the sample gas introduced into the particle sensor without external discharge of the sample gas; and a bypass line, one end of which is connected to a first position, which is a main line position between the mass flow rate regulator and the main line inlet end, and the other end of which is connected to a second position, which is a main line position between the particle sensor and the main line outlet end, through which the purge gas is bypassed during purging. According to the present invention, not only is external leakage of gas prevented during the analysis of the sample gas, but the accuracy and reliability of the gas analysis are also improved.

Description

Technology Field

[0001] The present invention relates to a gas particle counter for measuring particles in a gas. Background Technology

[0002] Recently, in the semiconductor and chemical industries, analytical devices capable of real-time monitoring of particles contained in samples (gases) are being required as essentials to manage the purity and safety of process gases.

[0003] However, conventional methods for measuring particles in gas utilize a pressure reducing device to maintain low pressure, allowing the particle counter's pump to draw in gas. This flow control method operates via mechanical control using a needle valve and a purge meter, and for precise flow control, a portion of the incoming gas is forcibly discharged to the outside.

[0004] As a result, there is a problem in that the use is restricted when the sample is a flammable or toxic hazardous gas, as it contaminates the working environment. In addition, there was a limitation in that the reliability and accuracy of the analysis data were reduced because it was difficult to correct in real time, even though the actual flow rate was variable depending on changes in external temperature or line pressure, and the mass flow rate of the sample entering the particle sensor could not be maintained at a constant level. Prior art literature

[0005] Republic of Korea Published Patent No. 10-1999-0056584 (Published July 15, 1999) Republic of Korea Published Patent No. 10-1998-0053056 (Published September 25, 1998) The problem to be solved

[0006] The objective of the present invention is to provide a gas particle counter that not only prevents external leakage of gas during the analysis of a sample gas but also maintains a constant flow rate and environment of the gas entering the particle sensor, thereby increasing the accuracy and reliability of the particle counter.

[0007] Another objective of the present invention is to provide a gas particle counter that enhances user convenience by simplifying the inspection of malfunctions, leaks, and contaminated parts of the components. means of solving the problem

[0008] To achieve the objective of the present invention, a gas particle counter comprises: a casing having an inlet port and an outlet port; a main line located inside the casing, with both ends connected to the inlet port and the outlet port of the casing, respectively, through which sample gas is introduced and discharged; a particle sensor connected to the main line to analyze particles of the sample gas flowing through the main line; a mass flow rate regulator connected to the main line to be positioned between the particle sensor and the inlet end of the main line, which regulates the flow rate of the sample gas introduced into the particle sensor without external discharge of the sample gas; and a bypass line, one end of which is connected to a first position, which is a main line position between the mass flow rate regulator and the main line inlet end, and the other end of which is connected to a second position, which is a main line position between the particle sensor and the main line outlet end, through which the purge gas is bypassed during purging.

[0009] It is preferable that the above-mentioned malfunction detection unit further includes a unit for checking whether the particle sensor is malfunctioning between the first position of the main line and the inlet end, and the malfunction detection unit includes a three-way valve provided in the main line so as to be located between the first position of the main line and the inlet end, a parallel line connecting the three-way valve and the third position of the main line which is between the three-way valve and the inlet end of the main line, and a filter mounted on the parallel line.

[0010] It is preferable that the component leakage detection unit further includes a component leakage detection unit connected to the main line to check for microleaks of the components connected to the main line, wherein the component leakage detection unit includes a first port provided on one side of the casing, a first connection line connecting the first port to a fourth position of the main line which is between the inlet end of the main line and a third position, a second valve mounted on the first connection line, and a third check valve connected to the first connection line so as to be positioned between the second valve and the fourth position.

[0011] The apparatus further includes a casing purging unit that continuously supplies nitrogen into the interior of the casing on one side of the casing to purge the interior of the casing and maintain the internal pressure of the casing at a positive pressure, wherein the casing purging unit preferably includes a second port provided on one side of the casing, a second connecting line connected to the second port so as to be located inside the casing, and an orifice gasket provided at the end of the second connecting line. Effects of the invention

[0012] The present invention includes a particle sensor for analyzing particles of a sample gas in a main line and a mass flow controller connected to the main line and equipped with internal closed-loop control to regulate the flow rate of the sample gas flowing into the particle sensor without external discharge of the sample gas. This eliminates the conventional bypass discharge structure that discharges a portion of the sample gas to the outside to regulate the flow rate of the sample gas flowing into the particle sensor, thereby preventing safety accidents caused by external discharge during the analysis of toxic or flammable hazardous gases, as well as enabling the amount of gas flowing into the particle sensor to be maintained constant regardless of changes in temperature and pressure. As a result, the accuracy and reliability of the analysis data are improved.

[0013] In addition, the present invention is equipped with a bypass line connecting the first and second positions of the main line, so that the purge gas can remove internal foreign substances from the main line without passing through the particle sensor before sample gas analysis, thereby increasing measurement precision and preventing contamination of the particle sensor and mass flow controller.

[0014] In addition, when the present invention is equipped with a malfunction inspection unit including a parallel line equipped with a three-way valve and a filter, the malfunction of the particle sensor can be inspected by the operation of the three-way valve, so the inspection of the particle sensor's malfunction becomes simple and easy.

[0015] In addition, when a component leak detection unit is provided in the main line, the present invention enables micro-leak inspection of the components constituting the device, thereby not only preventing external leakage of hazardous gas when the sample gas is hazardous gas but also simplifying the process of locating the component where the leak occurred.

[0016] In addition, when the present invention is equipped with a casing purging unit, when harmful gas is generated inside the casing, the harmful gas is diluted and discharged to the outside of the casing, and the inside of the casing is maintained in a positive pressure state higher than atmospheric pressure, thereby physically blocking external air and moisture from penetrating into the casing, thus preventing corrosion of precision parts placed inside the casing and preventing particle measurement errors caused by the influx of external particles. Brief explanation of the drawing

[0017] FIG. 1 is a front view illustrating an embodiment of a gas particle counter according to the present invention. FIG. 2 is a plan view illustrating an embodiment of a gas particle counter according to the present invention, FIG. 3 is a piping diagram illustrating an embodiment of a gas particle counter according to the present invention. Specific details for implementing the invention

[0018] Hereinafter, an embodiment of a gas particle counter according to the present invention will be described with reference to the attached drawings.

[0019] One embodiment of a gas particle counter according to the present invention includes a casing (10), a main line (20), a particle sensor (30), a mass flow controller (40), and a bypass line (50), as illustrated in 1, 2, and 3.

[0020] As an example of a casing (10), the casing (10) includes a casing body (11) in the shape of a cuboid and a plurality of ports provided on one side of the casing body (11). The ports are connected to an internal line located inside the casing (10) and an external line that may be located outside the casing (10), respectively, thereby connecting the external line and the internal line.

[0021] The shape of the casing body (11) can be formed in various shapes.

[0022] The ports may include an inlet port (12), an outlet port (13), a first port (14), and a second port (15).

[0024] It is preferable to further provide a monitoring computer (16) on the front of the casing body (11).

[0026] The main line (20) is located inside the casing (10), and both ends are connected to the inlet port (12) and outlet port (13) of the casing (10), respectively, so that sample gas is introduced and discharged.

[0027] The main line (20) has a set length, one end of which is connected to an inlet port (12) and the other end of which is connected to an outlet port (13), the end of the main line (20) connected to the inlet port (12) is called the inlet end, and the end of the main line (20) connected to the outlet port (13) is called the outlet end.

[0028] When a sample gas is introduced into the inlet end of the main line (20) through the inlet port (12), the sample gas flows through the main line (20) and exits outside the casing (10) through the outlet port (13), and when an external line is connected to the outlet port (13), it exits through the external line.

[0030] The particle sensor (30) is connected to the main line (20) and analyzes particles of the sample gas flowing through the main line (20).

[0032] The particle sensor (30) uses a mass flow regulator (40), which will be described later, to inject the gas to be measured into a chamber inside the sensor at a constant speed, and irradiates high-intensity light emitted from a laser diode onto the path through which the injected gas passes. When dust particles in the gas come into contact with the laser light, a scattering phenomenon occurs in which the light spreads in all directions, and the amount and intensity of the scattered light are detected by a light receiving unit and converted into the number and mass concentration of particles by size in μm units for real-time analysis. The particle sensor (30) is a known technology.

[0034] A mass flow controller (MFC) (40) is connected to the main line (20) so as to be positioned between the particle sensor (30) and the inlet end of the main line (20), and controls the flow rate of the sample gas flowing into the particle sensor (30) without external discharge of the sample gas.

[0035] The mass flow rate controller (40) is a closed-loop control device that uses the thermal conductivity of the gas or the Coriolis force to precisely measure the mass flow rate and automatically controls the internal valve to maintain the set flow rate, thereby increasing the precision of sample gas analysis in the particle sensor (30) by supplying a constant flow rate without being affected by changes in temperature and pressure.

[0037] One end of the bypass line (50) is connected to a first position (1), which is a location on the main line (20) between the mass flow controller (40) and the main line (20) inlet end, and the other end is connected to a second position (2), which is a location on the main line (20) between the particle sensor (30) and the main line (20) outlet end, so that the purge gas is bypassed so that it does not pass through the mass flow controller (40) and the particle sensor (30) during purging.

[0038] As an example of a bypass line (50), the bypass line (50) includes a connecting line (51) connecting a first position (1) and a second position (2) of a main line (20), a first valve (52) mounted on the connecting line (51) adjacent to the first position (1) to control the gas flow rate, a first check valve (53) mounted on the connecting line (51) to be located between the first valve (52) and the second position (2), and an orifice gasket (54) mounted on the connecting line (51) to be located between the first check valve (53) and the second position (2). A second check valve (55) is mounted on the main line (20) to be located between the second position (2) of the main line (20) and the particle sensor (30). The first valve (52) is preferably a manual and pneumatic valve.

[0040] It is preferable that a first pressure indicator transmitter (PIT) (21) be provided between the first position (1) of the main line (20) and the inlet end, and that a second pressure indicator transmitter (22) be provided in the main line (20) located between the second check valve (55) and the particle sensor (30).

[0042] In one embodiment of the gas particle counter according to the present invention, when analyzing gas, the main line (20) is first purged to remove internal foreign substances. When purging the main line (20), the purging gas is injected into the inlet end of the main line (20) while the gas inflow is blocked by the mass flow controller (40). The purging gas then flows from the main line (20) to the first position (1), the bypass line (50), the second position (2), the main line (20), and the outlet end of the main line (20), thereby purging the main line (20). As a result, the main line (20) is purged without contaminating the particle sensor (30) and the mass flow controller (40).

[0043] When analyzing the sample gas after the purging of the main line (20) is performed, an injection external line (not shown) for injecting the sample gas into the inlet port (12) on the outside of the casing (10) is connected while the gas inflow of the mass flow controller (40) is allowed, and an exhaust external line (not shown) for discharging the sample gas into the outlet port (13) is connected, and the sample gas is injected through the injection external line. The sample gas injected through the injection external line flows into the main line (20) through the inlet end of the main line (20). The sample gas flowing through the main line (20) has its flow rate controlled through the mass flow controller (40) so that the sample gas is not discharged to the outside, and then flows into the particle sensor (30). As the sample gas is analyzed in real time at the particle sensor (30), it is discharged through the main line (20) to the outlet end of the main line (20).

[0045] Meanwhile, it is preferable to further include a malfunction inspection unit (60) that checks whether there is a malfunction of the particle sensor (30) between the first position (1) of the main line (20) and the inflow end.

[0046] As an example of a malfunction inspection unit (60), the malfunction inspection unit (60) includes a three-way valve (61) provided in the main line (20) to be located between the first position (1) of the main line (20) and the inlet end, a parallel line (62) connecting the three-way valve (61) and the third position (3) of the main line (20) which is between the inlet end of the main line (20), and a filter (63) mounted on the parallel line (62).

[0047] When the analysis of the sample gas is performed, the flow path of the three-way valve of the malfunction inspection unit (60) is adjusted so that the sample gas flowing through the inlet end of the main line (20) flows directly into the mass flow controller (40) without passing through the filter (63) of the malfunction inspection unit (60). As a result, the sample gas flowing through the inlet end of the main line (20) flows directly into the mass flow controller (40) without passing through the filter (63) of the malfunction inspection unit (60), and the flow rate is controlled by the mass flow controller (40) and flows into the particle sensor (30) to analyze the sample gas. If no particles are analyzed in the sample gas, the presence or absence of a malfunction in the particle sensor (30) is checked. When checking for malfunctions, the flow path of the three-way valve of the malfunction inspection unit (60) is adjusted so that the sample gas flowing through the inlet end of the main line (20) passes through the filter (63) of the malfunction inspection unit (60) and flows into the mass flow controller (40). As a result, the sample gas flowing through the inlet end of the main line (20) flows into the parallel line (62) and passes through the filter (63), where particles of the sample gas are removed by the filter (63). The sample gas from which the particles have been removed then flows into the particle sensor (30) through the mass flow controller (40) and analyzes the sample gas at the particle sensor (30). As a result, if no particles are analyzed in the sample gas, it is determined to be normal, and if particles are analyzed, it is determined to be a malfunction, and the particle sensor (30) is replaced.

[0049] It is preferable to further include a component leakage detection unit (70) connected to the main line (20) to check for minute leaks in the components connected to the main line (20).

[0050] As an example of a component leak detection unit (70), the component leak detection unit (70) includes a first port (14) provided on one side of a casing (10), a first connecting line (71) connecting the first port (14) to a fourth position (4) of the main line (20) which is between the inlet end of the main line (20) and a third position (3), a second valve (72) mounted on the first connecting line (71), a third check valve (73) connected to the first connecting line (71) so as to be located between the second valve (72) and the fourth position (4), and an air regulator (74) connected to the first connecting line (71). Additionally, a third valve (75) may be further provided on the main line (20) so as to be located between the fourth position (4) of the main line (20) and a first pressure indicator transmitter (21).

[0051] The component leak detection unit (70) determines that there is no leak if the set air pressure does not change while the air pressure is applied to the first port (14) and maintained for a certain period of time, and considers that a minor leak has occurred in the component if the air pressure changes. Specifically, when checking a component with a minor leak, the leaking component is checked by opening and closing the first, second, and third valves. Another purpose is to prevent damage to the component by monitoring the allowable pressure of each component.

[0053] Additionally, it is preferable to further include a casing purging unit (80) that continuously supplies nitrogen into the interior of the casing (10) on one side of the casing (10) to purge the interior of the casing (10) and maintain the internal pressure of the casing (10) at a positive pressure.

[0054] As an example of a casing purging unit (80), the casing purging unit (80) includes a second port (15) provided on one side of a casing (10), a second connecting line (81) connected to the second port (15) so as to be located inside the casing (10), and an orifice gasket (82) provided at the end of the second connecting line (81).

[0055] A nitrogen supply unit (not shown) is connected to the second port (15) of the casing purging unit (80), and when nitrogen is supplied from the nitrogen supply unit, the nitrogen is injected into the casing (10) through the second connection line (81) and the orifice gasket (82). As nitrogen is injected into the casing (10), particles that may remain inside the casing (10) are discharged to the outside of the casing (10), as well as harmful gases are diluted and discharged to the outside of the casing (10), and the inside of the casing (10) becomes a positive pressure state, thereby preventing external air, moisture, particles, etc. from entering the casing (10).

[0057] Thus, the present invention includes a particle sensor (30) for analyzing particles of sample gas in a main line (20) and a mass flow rate controller (40) connected to the main line (20) and equipped with internal closed-loop control to regulate the flow rate of sample gas flowing into the particle sensor (30) without external discharge of sample gas. Therefore, the conventional bypass discharge structure, which discharged a portion of the sample gas to the outside to regulate the flow rate of sample gas flowing into the particle sensor (30), is eliminated. This prevents safety accidents caused by external discharge during the analysis of toxic or flammable hazardous gases, and allows the amount of gas flowing into the particle sensor (30) to be maintained constant regardless of changes in temperature and pressure. As a result, the accuracy and reliability of the analysis data are improved.

[0058] In addition, the present invention is provided with a bypass line (50) connecting the first position (1) and the second position (2) of the main line (20), so that the purge gas can remove foreign substances inside the main line (20) without passing through the particle sensor (30) before sample gas analysis, thereby increasing the measurement precision and preventing contamination of the particle sensor (30) and the mass flow controller (40).

[0059] In addition, when the present invention is equipped with a malfunction inspection unit (60) including a parallel line (62) equipped with a three-way valve (61) and a filter (63), the malfunction of the particle sensor (30) can be inspected by the operation of the three-way valve (61), so the malfunction inspection of the particle sensor (30) becomes simple and easy.

[0060] In addition, when a component leak detection unit (70) is provided in the main line (20) of the present invention, it is possible to check for minute leaks in the components constituting the device, thereby preventing external leakage of the harmful gas when the sample gas is a harmful gas, and also making it simple to locate the component where the leak occurred.

[0061] In addition, when the present invention is equipped with a casing purging unit (80), when harmful gas is generated inside the casing (10), the harmful gas is diluted and discharged to the outside of the casing (10), and the inside of the casing (10) is maintained in a positive pressure state higher than atmospheric pressure, thereby physically blocking external air and moisture from penetrating into the casing (10), thus preventing corrosion of precision parts placed inside the casing (10) and preventing particle measurement errors caused by the inflow of external particles. Explanation of the symbols

[0062] 10; Casing 20; Mainline 30; Particle sensor 40; Mass flow controller 50; Bypass line 60; Malfunction detection unit 70; Component leak detection unit 80; Casing purging unit

Claims

Claim 1 A casing equipped with an inlet port and an outlet port; a main line located inside the casing, with both ends connected to the inlet port and the outlet port of the casing, respectively, through which sample gas is introduced and discharged; a particle sensor connected to the main line for analyzing particles of the sample gas flowing through the main line; and a mass flow controller connected to the main line so as to be positioned between the particle sensor and the inlet end of the main line, for controlling the flow rate of the sample gas introduced into the particle sensor without external discharge of the sample gas. A gas particle counter comprising a bypass line in which one end is connected to a first position, which is a main line position between the mass flow controller and the main line inlet end, and the other end is connected to a second position, which is a main line position between the particle sensor and the main line outlet end, so as to bypass the purge gas during purging, and further comprising a malfunction inspection unit for checking whether the particle sensor is malfunctioning between the first position and the inlet end of the main line, wherein the malfunction inspection unit comprises a three-way valve provided in the main line to be located between the first position and the inlet end of the main line, a parallel line connecting the three-way valve and the third position of the main line between the three-way valve and the inlet end of the main line, and a filter mounted on the parallel line. Claim 2 delete Claim 3 A gas particle counter according to claim 1, further comprising a component leak detection unit connected to the main line to check for microleaks of components connected to the main line, wherein the component leak detection unit comprises a first port provided on one side of the casing, a first connecting line connecting the first port to a fourth position of the main line which is between the inlet end of the main line and a third position, a second valve mounted on the first connecting line, and a third check valve connected to the first connecting line to be positioned between the second valve and the fourth position. Claim 4 A gas particle counter according to claim 1, further comprising a casing purging unit that continuously supplies nitrogen into the interior of the casing on one side of the casing to purge the interior of the casing and maintains the internal pressure of the casing at a positive pressure, wherein the casing purging unit comprises a second port provided on one side of the casing, a second connecting line connected to the second port so as to be located inside the casing, and an orifice gasket provided at the end of the second connecting line.

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