Gas analysis device and gas flow path switching device

Abstract

A gas flow path switching device (1) comprises: a plate-like flow path plate (250); a first microvalve (201); and a second microvalve (202). A first flow path (271), a second flow path (272), and a third flow path (273) are formed in the flow path plate (250). The first microvalve (201) is configured to be able to switch connection and disconnection between the first flow path (271) and the second flow path (272). The second microvalve (202) is configured to be able to switch connection and disconnection between the first flow path (271) and the third flow path (273). The first microvalve (201) and the second microvalve (202) are arranged on both surfaces (250a, 250b) of the flow path plate (250).

Description

Gas analyzer and gas flow path switching device

[0001] The present disclosure relates to a gas analyzer and a gas flow path switching device.

[0002] Gas chromatography is an analytical technique that detects components in a gas by separating them using a separation column. Because gas chromatography can analyze a wide variety of components, there are currently gas analyzers with columns and flow path configurations that have various separation characteristics.

[0003] For example, among conventional gas analyzers, there are gas analyzers that are configured to use a switching valve to switch the connection pattern between a detection device that detects gas components and multiple separation columns (see Agilent Technologies, Inc., Application "GC Analysis of Refinery Gas (RGA)," 5989-7439JAJP (Non-Patent Document 1)).

[0004] Agilent Technologies, Inc. Application "GC Analysis of Refinery Gas (RGA)" 5989-7439JAJP

[0005] In the gas analyzer described above, switching of the gas flow paths is performed using a switching valve. When using a switching valve to switch the connection of the first flow path from the second flow path to the third flow path, if the dead volume at the connection between the first flow path and the third flow path is large, carryover and contamination may occur during the switching. Specifically, before the flow path switching, the sample that should be supplied to the second flow path may not be supplied to the second flow path but may remain in the dead volume. After the flow path switching, the sample that remained in the dead volume may be supplied to the third flow path, which may result in carryover or contamination.

[0006] The present disclosure has been made to solve the above problems, and an object of the present disclosure is to provide a gas analyzer and a gas flow path switching device with a small dead volume.

[0007] A gas analyzer according to the present disclosure includes an inlet for a sample gas, an analysis unit for analyzing gas components contained in the sample gas, a flow path provided between the inlet and the analysis unit and having a branch portion, and a gas flow path switching unit provided at the branch portion of the flow path. The gas flow path switching unit includes a flow path plate having a first main surface and a second main surface opposite to the first main surface, with a first flow path, a second flow path, and a third flow path formed between the first and second main surfaces, a first valve disposed on the first main surface and configured to switch between connecting and disconnecting the first flow path and the second flow path, and a second valve disposed on the second main surface and configured to switch between connecting and disconnecting the first flow path and the third flow path.

[0008] The gas flow path switching device according to the present disclosure is a gas flow path switching device for switching gas flow paths, and includes: a flow path plate having a first main surface and a second main surface opposite the first main surface, with a first flow path, a second flow path, and a third flow path formed between the first main surface and the second main surface; a first valve disposed on the first main surface and configured to be able to switch between connecting and blocking communication between the first flow path and the second flow path; and a second valve disposed on the second main surface and configured to be able to switch between connecting and blocking communication between the first flow path and the third flow path.

[0009] According to the present disclosure, the first valve and the second valve are respectively arranged on both sides (first main surface and second main surface) of the flow path plate. Therefore, compared to when the first valve and the second valve are arranged side by side on one side of the flow path plate, the dead volume during flow path switching by the first valve and the second valve can be reduced. As a result, carryover and contamination due to flow path switching can be suppressed.

[0010] 1 is a perspective view schematically showing an example of the configuration of a gas flow path switching device; FIG. 2 is a diagram showing an example of the internal structure of a flow path plate, a first microvalve, and a second microvalve; FIG. 3 is a diagram showing a state in which the first microvalve is open and the second microvalve is closed; FIG. 4 is a diagram showing a state in which the first microvalve is closed and the second microvalve is open; FIG. 5 is a diagram comparing dead volumes in a configuration of a comparative example with dead volumes in a configuration of the present embodiment; FIG. 1 is a diagram (part 1) showing a schematic example of the overall configuration of a gas analyzer; FIG. 2 is a diagram (part 2) showing an operation pattern of the analyzer; FIG. 3 is a diagram (part 3) showing an operation pattern of the analyzer; FIG. 4 is a diagram (part 4) showing an operation pattern of the analyzer; FIG. 5 is a diagram (part 5) showing an operation pattern of the analyzer; FIG. 6 is a diagram (part 6) showing an operation pattern of the analyzer.

[0011] The present embodiment will now be described in detail with reference to the drawings, in which the same or corresponding parts in the drawings are designated by the same reference numerals and description thereof will not be repeated.

[0012] 1 is a perspective view schematically illustrating an example of the configuration of a gas flow path switching device 1 according to this embodiment 1. The gas flow path switching device 1 is a device used in a gas chromatograph or the like for switching gas flow paths.

[0013] The gas flow path switching device 1 includes a plate-shaped flow path plate 250 , a first microvalve 201 , and a second microvalve 202 .

[0014] Flow path plate 250 is a plate-like member having a first main surface (hereinafter also referred to as the "upper surface") 250a and a second main surface (hereinafter also referred to as the "lower surface") 250b opposite the first main surface. Flow path plate 250 has a first plate 260 and a second plate 270. First plate 260 and second plate 270 are plate-like members made of metal (for example, stainless steel), and are stacked and diffusion-bonded to each other. Flow path plate 250, first microvalve 201, and second microvalve 202 may correspond to the "flow path plate," "first valve," and "second valve" in this disclosure, respectively.

[0015] Groove-shaped first flow path 271, second flow path 272, and third flow path 273 are formed on the surface of second plate 270 that is joined to first plate 260. When first plate 260 is disposed on second plate 270, the opening portions on the upper surface side of first flow path 271, second flow path 272, and third flow path 273 are blocked by first plate 260. First flow path 271, second flow path 272, and third flow path 273 may correspond to the "first flow path," "second flow path," and "third flow path," respectively, in this disclosure.

[0016] 1, the normal direction of the flow path plate 250 may be referred to as the "Z-axis direction," the extension direction of the first flow path 271 may be referred to as the "X-axis direction," and the direction perpendicular to the Z-axis and X-axis directions may be referred to as the "Y-axis direction." Furthermore, the positive Z-axis direction (the direction from the second plate 270 toward the first plate 260) may be referred to as the "upward direction," and the negative Z-axis direction (the direction from the first plate 260 toward the second plate 270) may be referred to as the "downward direction."

[0017] The first plate 260 is formed with five cylindrical communication passages 261 to 265, each extending along the Z-axis direction and penetrating the first plate 260. The communication passage 261 connects the upper surface of the end of the first flow passage 271 on the positive X-axis direction side with the upper surface 250a of the flow passage plate 250. The communication passage 262 connects the upper surface of the end of the first flow passage 271 on the negative X-axis direction side with the upper surface 250a of the flow passage plate 250. The communication passage 263 connects the upper surface of the end of the second flow passage 272 on the positive X-axis direction side with the upper surface 250a of the flow passage plate 250. The communication passage 264 connects the upper surface of the end of the second flow passage 272 on the negative X-axis direction side with the upper surface 250a of the flow passage plate 250. The communication passage 265 communicates the upper surface of the end of the third passage 273 on the negative side of the X axis with the upper surface 250 a of the passage plate 250 .

[0018] In addition to the first to third flow paths 271 to 273 described above, two cylindrical communication paths 274, 275 each extending along the Z-axis direction are formed in the second plate 270. The communication path 274 connects the lower surface of the end of the first flow path 271 on the negative X-axis direction side with the lower surface 250b of the flow path plate 250. The communication path 275 connects the lower surface of the end of the third flow path 273 on the positive X-axis direction side with the lower surface 250b of the flow path plate 250.

[0019] First microvalve 201 is disposed on upper surface 250a of flow path plate 250, and is configured to be able to switch between connecting and blocking communication between first flow path 271 and second flow path 272. Specifically, first microvalve 201 is connected to communication paths 262 and 263 of first plate 260, and is configured to be able to switch between connecting and blocking communication between communication paths 262 and 263. Communication paths 262 and 263 may correspond to the "first communication path" and "second communication path," respectively, in this disclosure.

[0020] Second microvalve 202 is disposed on lower surface 250b of flow path plate 250, and is configured to be able to switch between connecting and blocking communication between first flow path 271 and third flow path 273. Specifically, second microvalve 202 is connected to communication paths 274 and 275 of second plate 270, and is configured to be able to switch between connecting and blocking communication between communication paths 274 and 275. Communication paths 274 and 275 may correspond to the "third communication path" and "fourth communication path" of the present disclosure, respectively.

[0021] FIG. 2 shows an example of the internal structure of the flow path plate 250, the first microvalve 201, and the second microvalve 202. The upper part of FIG. 2 shows cross-sectional views of the flow path plate 250, the first microvalve 201, and the second microvalve 202. The lower part of FIG. 2 shows a plan view of the flow path plate 250 and the base layer 220 (described below) of the first microvalve 201 as viewed from the Z-axis direction. The thickness (dimension in the Z-axis direction) of the first plate 260 of the flow path plate 250 is, for example, approximately 0.3 mm, and the thickness of the second microvalve 202 of the flow path plate 250 is, for example, approximately 0.5 mm. The dimensions of the first microvalve 201 and the second microvalve 202 in the X-axis direction, Y-axis direction, and Z-axis direction are, for example, approximately 7 mm, 7 mm, and 1 mm, respectively.

[0022] The first microvalve 201 has a three-layer structure including a base layer 220, a diaphragm layer 230, and a cover layer 240, which are stacked in this order. Each of the base layer 220, the diaphragm layer 230, and the cover layer 240 is made of, for example, silicon, and is microfabricated using MEMS (Micro Electric Mechanical Systems) technology to achieve the desired strength and flexibility.

[0023] The base layer 220 is disposed on the bottom layer of the first microvalve 201 (the layer closest to the flow path plate 250). The base layer 220 has a recess 221 recessed from the top surface to the bottom surface of the base layer 220, and openings 223 and 224 penetrating the base layer 220. The recess 221 has a substantially circular shape when the base layer 220 is viewed in a plan view from the Z-axis direction (see the lower part of FIG. 2). The diameter of the recess 221 is, for example, approximately 5 mm.

[0024] The openings 223 and 224 are formed in the bottom 225 of the recess 221. The opening 223 is located near the center of the bottom 225 when viewed from above in the Z-axis direction, and is connected to a communication path 262 in the first plate 260 of the flow path plate 250. The opening 224 is located a predetermined distance away from the center of the bottom 225 in the negative Y-axis direction when viewed from above in the Z-axis direction, and is connected to a communication path 263 in the first plate 260 of the flow path plate 250. The openings 223 and 224 of the first microvalve 201 serve as inlets and outlets for the sample gas in the first microvalve 201. The diameter of the openings 223 and 224 is, for example, approximately 0.3 mm. The height (dimension in the Z-axis direction) of the openings 223 and 224 is, for example, approximately 0.48 mm.

[0025] The diaphragm layer 230 is disposed on the upper surface side of the base layer 220, facing the base layer 220. The diaphragm layer 230 has a rigid portion 234 and a flexible portion 233 provided around the rigid portion 234. The rigid portion 234 has a substantially circular shape when the diaphragm layer 230 is viewed in a plan view from the Z-axis direction. The flexible portion 233 is thinner than the rigid portion 234 and is flexible. Elastic deformation of the flexible portion 233 causes displacement of the rigid portion 234 in the Z-axis direction.

[0026] The cover layer 240 is disposed on the upper surface of the diaphragm layer 230 so as to cover the diaphragm layer 230. This forms a fluid space 235 between the cover layer 240 and the diaphragm layer 230. The fluid space 235 is in communication with a supply port for a control fluid (pneumatic fluid) not shown.

[0027] The base layer 220, the opening 223, and the opening 224 of the first microvalve 201 may correspond to the "first base portion," the "first opening," and the "second opening," respectively, of this disclosure. The diaphragm layer 230 of the first microvalve 201 may correspond to the "first diaphragm portion" of this disclosure.

[0028] The second microvalve 202 has basically the same configuration as the first microvalve 201. That is, like the first microvalve 201, the second microvalve 202 also has a three-layer structure in which a silicon base layer 220, a diaphragm layer 230, and a cover layer 240 are laminated, and is microfabricated using MEMS technology. The size of the second microvalve 202 is also the same as that of the first microvalve 201.

[0029] The second microvalve 202 is disposed at a position that is obtained by inverting the first microvalve 201 by 180 degrees around the X axis, with the first flow path 271 as the center. The second microvalve 202 overlaps with the first microvalve 201 when viewed from the Z axis direction.

[0030] Openings 223 and 224 of base layer 220 of second microvalve 202 are connected to communication paths 274 and 275, respectively, of flow path plate 250. Openings 223 and 224 of second microvalve 202 serve as an inlet and outlet for sample gas in second microvalve 202.

[0031] The base layer 220, the opening 223, and the opening 224 of the second microvalve 202 may correspond to the "second base portion," the "third opening," and the "fourth opening" of this disclosure, respectively. The diaphragm layer 230 of the second microvalve 202 may correspond to the "second diaphragm portion" of this disclosure.

[0032] Both the first microvalve 201 and the second microvalve 202 are so-called normally open type valves that are open in an initial state (normal state) when no pneumatic fluid is supplied to the fluid space 235, and are closed when pneumatic fluid is supplied to the fluid space 235. Figure 2 shows the first microvalve 201 and the second microvalve 202 in their initial state (open state).

[0033] 2, when no pneumatic fluid is supplied to fluid space 235, rigid portion 234 and flexible portion 233 of diaphragm layer 230 are held apart from bottom 225 of recess 221 in base layer 220. As a result, openings 223 and 224, which are inlet and outlet ports for sample gas, are in an open state where they communicate with each other.

[0034] On the other hand, when pneumatic fluid is supplied to fluid space 235, flexible portion 233 of diaphragm layer 230 is pushed by the pneumatic fluid and elastically deforms, causing rigid portion 234 and flexible portion 233 of diaphragm layer 230 to displace toward bottom 225 of recess 221 in base layer 220 and come into close contact with bottom 225 of recess 221 in base layer 220. This results in a closed state in which openings 223 and 224, which are inlet and outlet ports for sample gas, are blocked. Note that instead of driving (displacing) rigid portion 234 with pneumatic fluid, rigid portion 234 may be electrically driven (displaced) using a piezoelectric element or the like.

[0035] 3 is a diagram showing a state in which the first microvalve 201 is open and the second microvalve 202 is closed. In this state, the first flow path 271 and the third flow path 273 are blocked by the second microvalve 202, and the first flow path 271 and the second flow path 272 are connected via the first microvalve 201. As a result, the first flow path 271 is connected to the second flow path 272.

[0036] 4 is a diagram showing a state in which the first microvalve 201 is closed and the second microvalve 202 is open. In this state, the first flow path 271 and the second flow path 272 are blocked by the first microvalve 201, and the first flow path 271 and the third flow path 273 are connected via the second microvalve 202. As a result, the connection destination of the first flow path 271 is switched to the third flow path 273.

[0037] As described above, in the gas flow path switching device 1 according to the first embodiment, the first microvalve 201 and the second microvalve 202 are disposed on both sides (upper surface 250a and lower surface 250b) of the flow path plate 250. Therefore, the dead volume during flow path switching by the first microvalve 201 and the second microvalve 202 can be made smaller than when the first microvalve 201 and the second microvalve 202 are disposed side by side on one side (upper surface 250a or lower surface 250b) of the flow path plate 250. As a result, carryover and contamination caused by flow path switching can be suppressed.

[0038] FIG. 5 is a diagram comparing a dead volume DV1 in the configuration of the comparative example with a dead volume DV2 in the configuration of this embodiment.

[0039] The comparative example has a horizontal configuration in which the first microvalve 201 and the second microvalve 202 are arranged side by side in the Y-axis direction on one side of the flow path plate 250. In the comparative example, branch paths Y1 and Y2 are formed extending in the positive and negative Y-axis directions from the end of the first flow path 271 in the positive X-axis direction to connect the first microvalve 201 and the second microvalve 202. Therefore, as illustrated in FIG. 5 , even when the second microvalve 202 is closed, the dead volume DV1 between the first flow path 271 and the second microvalve 202 includes the branch path Y2 extending in the Y-axis direction.

[0040] On the other hand, the configuration of this embodiment is a vertical configuration in which the first microvalve 201 and the second microvalve 202 are arranged on both sides of the flow path plate 250 and are positioned so that they overlap each other when viewed from above in the Z-axis direction. Therefore, the configuration of this embodiment does not require the formation of branch paths Y1 and Y2 extending in the Y-axis direction, which were necessary in the configuration of the comparative example, and therefore the dead volume DV2 between the first flow path 271 and the second microvalve 202 can be reduced accordingly.

[0041] Furthermore, in the configuration of this embodiment, the first microvalve 201 and the second microvalve 202 are not arranged side by side in the Y-axis direction, but are arranged overlapping in the Z-axis direction, which allows the size of the gas flow path switching device 1 in the Y-axis direction to be reduced.

[0042] Furthermore, in the gas flow path switching device 1 according to the first embodiment, the first microvalve 201 and the second microvalve 202 are microfabricated using MEMS technology, which makes it possible to make the dead volumes inside the first microvalve 201 and the second microvalve 202 extremely small.

[0043] In the gas flow path switching device 1 according to the first embodiment, the first microvalve 201 and the second microvalve 202 completely overlap each other when viewed in a plane from the Z-axis direction, but this is not necessarily required and only a partial overlap is required. Even if the first microvalve 201 and the second microvalve 202 only partially overlap when viewed in a plane from the Z-axis direction, the volume of the branch path extending in the Y-axis direction can be reduced compared to when they do not overlap at all, and the dead volume can be reduced accordingly.

[0044] 6 is a diagram schematically illustrating an example of the overall configuration of a gas analyzer 2 according to the present embodiment 2. The gas analyzer 2 includes the gas flow path switching device 1 according to the above-described first embodiment.

[0045] The gas analyzer 2 includes an analyzer 3, an input device 60, a display device 70, a drive device 80, and a control device 100. The analyzer 3 includes carrier gas supply devices 11 and 12, a sample tank 20 that stores the sample gas to be analyzed, switching modules M1 and M2, columns 41 and 42, loops 43 and 44, a restrictor 45, and detection devices 51 and 52.

[0046] The carrier gas supply unit (AFC) 11 adjusts the flow rate and pressure of the carrier gas (mobile phase) and outputs it to the switching module M1. A sample tank 20 is disposed in the flow path between the AFC 11 and the switching module M1, so that the sample gas in the sample tank 20 is supplied to the switching module M1 together with the carrier gas. The carrier gas supply unit (APC) 12 adjusts the pressure of the carrier gas and outputs it to the switching module M1. Hereinafter, the pressure of the carrier gas output from the AFC 11 will also be referred to as "pressure P1," and the pressure of the carrier gas output from the APC 12 will also be referred to as "pressure P2."

[0047] The switching modules M1 and M2 are provided on flow paths that are fluidically connected to the sample tank 20, columns 41 and 42, loops 43 and 44, restrictor 45, and detection devices 51 and 52. Note that fluid connection here means being connected by a fluid directly without passing through other components, or indirectly via other components.

[0048] Each of the switching modules M1 and M2 is formed by mounting a plurality of valves on a flow path plate on which a flow path pattern is formed. Specifically, four microvalves V1 to V4 are mounted on the switching module M1, and four microvalves V6 to V9 are mounted on the switching module M2. By switching the opening / closing operation patterns of the microvalves V1 to V4 and V6 to V9 in a predetermined order, the components contained in the sample gas in the sample tank 20 are analyzed by the analyzer 3.

[0049] The microvalves V1 to V4 and V6 to V9 are switched between an open state and a closed state by the driving device 80. In Figure 6 and subsequent figures, microvalves marked with an x ​​are in the closed state, and microvalves without an x ​​are in the open state.

[0050] The driving device 80 switches the states of the microvalves V1 to V4 and V6 to V9 in response to commands from the control device 100. In other words, the states of the microvalves V1 to V4 and V6 to V9 are controlled by the control device 100.

[0051] The configuration of the gas flow path switching device 1 according to the above-described embodiment 1 is applied to at least one of the switching unit 1A including microvalves V1 and V2, the switching unit 1B including microvalves V3 and V4, the switching unit 1C including microvalves V6 and V7, and the switching unit 1D including microvalves V8 and V9 in the analysis device 3 of FIG. 6.

[0052] Columns 41 and 42 separate various components in the supplied sample gas. Specifically, columns 41 and 42 separate and output various components contained in the supplied sample gas in the time direction while the sample gas passes through each column on the flow of carrier gas. In this embodiment, column 41 is a column for primary separation. Column 42 is a column for secondary separation that further separates the various components of the sample gas that have been primarily separated by column 41.

[0053] The loops 43 and 44 are tubes for temporarily storing the sample gas and are not capable of separating the various components of the sample gas. The restrictor 45 is a resistance tube for adjusting the pressure and is not capable of separating the various components of the sample gas.

[0054] The detector 51 is connected to the column 42 and detects various gas components introduced from the column 42. The detector 52 is connected to the restrictor 45 and detects various gas components introduced from the restrictor 45. Data indicating the detection results by the detectors 51 and 52 is stored in the memory unit 120 in the control device 100 and is displayed on the display device 70 at the request of the user.

[0055] The input device 60 is, for example, a keyboard or a pointing device such as a mouse, and receives requests or commands from a user. The requests or commands inputted by the user to the input device 60 are sent to the control device 100.

[0056] The display device 70 is configured by, for example, a liquid crystal display (LCD) panel, and displays information to the user. When a touch panel is used as the user interface, the input device 60 and the display device 70 are integrally formed.

[0057] The control device 100 includes a calculation unit 110, a storage unit 120, an input / output interface, etc. The control device 100 comprehensively controls the entire gas analyzer 2, including the AFC 11, APC 12, microvalves V1 to V4, V6 to V9 (drive device 80), etc. in the analyzer 3. The control device 100 is connected to an input device 60 and a display device 70, which are user interfaces, by wire or wirelessly.

[0058] The calculation unit 110 has a calculation device (Central Processing Unit) and generates control signals for controlling each of the microvalves V1 to V4, V6 to V9 using information stored in the memory unit 120, and outputs the generated control signals to the microvalves V1 to V4, V6 to V9 (drive device 80) via an output interface.

[0059] <Operation Patterns of the Analytical Apparatus> FIGS. 7 and 8 are diagrams showing operation patterns A to H of the analytical apparatus 3 when the column 41 is used as a column for primary separation and the column 42 is used as a column for secondary separation.

[0060] In operation pattern A (initial state), microvalves V1, V3, V7, and V8 are opened, and the other microvalves V2, V4, V6, and V9 are closed. Furthermore, pressure P1 is controlled to a value greater than pressure P2. As a result, the first carrier gas output from AFC 11 is supplied to detector 52 through column 41, loop 43, and restrictor 45, and the second carrier gas output from APC 12 is supplied to detector 51 through loop 44 and column 42.

[0061] In the next operation pattern B, the sample gas in the sample tank 20 is injected into the column 41, and primary separation of the sample gas is performed. Note that Fig. 7 shows an example in which the sample gas supplied to the column 41 is separated by primary separation into a component S1 that elutes early, a component S2 that elutes slower than component S1, and a component S3 that elutes slower than component S2.

[0062] In the next operation pattern C, component S1, which elutes early from column 41, is supplied to loop 43.

[0063] Thereafter, the operation pattern of the analyzer 3 is switched to the next operation pattern D. In operation pattern D, microvalves V1, V4, V6, and V9 are opened, and the other microvalves V2, V3, V7, and V8 are closed. As a result, the connection destination of the outlet of column 41 is switched from loop 43 to loop 44, and the connection destination of the outlet of loop 43 is switched from restrictor 45 to column 42. Therefore, component S1 is supplied from loop 43 to column 42 and subjected to secondary separation in column 42, and component S2 is supplied from column 41 to loop 44.

[0064] Since the configuration of the gas flow path switching device 1 according to the first embodiment described above is employed for flow path switching using the microvalves V3 and V4, the dead volume during flow path switching using the microvalves V3 and V4 is reduced, thereby preventing carryover and contamination that may occur when flow path switching is performed from operation pattern C to operation pattern D.

[0065] Thereafter, the operation pattern of the analyzer 3 is switched to the next operation pattern E. In operation pattern E, microvalves V1, V3, V7, and V8 are opened, and the other microvalves V2, V4, V6, and V9 are closed. As a result, the connection destination of the outlet of column 41 is switched from loop 44 to loop 43, and the connection destination of the outlet of loop 44 is switched from restrictor 45 to column 42. Therefore, component S1 is eluted from column 42 and supplied to detection device 51 for detection, component S2 is supplied from loop 44 to column 42 for secondary separation, and component S3 is eluted from column 41 and supplied to loop 43.

[0066] Thereafter, the operation pattern of the analyzer 3 is switched to the next operation pattern F (backflush). In operation pattern F, the states of the microvalves V1 to V4 and V6 to V9 are maintained as in operation pattern E, and pressure P1 is reduced to a value lower than pressure P2. This reverses the flow direction of the carrier gas in the column 41, and the sample gas remaining in the column 41 is discharged from a vent (not shown).

[0067] FIG. 9 shows operation patterns G and H of the analyzer 3 when the columns 41 and 42 are used independently.

[0068] In operation pattern G, microvalves V1, V3, V7, and V8 are opened, and the other microvalves V2, V4, V6, and V9 are closed. As a result, the first carrier gas output from the AFC 11 passes through the column 41, the loop 43, and the restrictor 45 and is supplied to the detector 52. As a result, the components S1 to S3 separated in the column 41 are detected by the detector 52.

[0069] In operation pattern H, microvalves V2, V7, and V8 are opened, and the other microvalves V1, V3, V4, V6, and V9 are closed. As a result, the first carrier gas output from the AFC 11 is supplied to the detector 52 through the loop 44 and column 42. As a result, components S1 to S3 separated in the column 42 are detected by the detector 51.

[0070] As described above, the gas analyzer 2 according to the second embodiment employs the configuration of the gas flow path switching device 1 according to the first embodiment as the configuration of the gas flow path switching mechanism. Therefore, carryover and contamination caused by flow path switching can be prevented. Furthermore, compared to when a modulator using a refrigerant is employed as the configuration of the gas flow path switching mechanism, the configuration of the switching mechanism can be simplified and the flow path switching time can be shortened.

[0071] 10 is a diagram schematically illustrating an example of the overall configuration of a gas analyzer 2A according to Modification 1. The gas analyzer 2A is obtained by changing the analyzer 3 of the gas analyzer 2 described above to an analyzer 3A.

[0072] The analytical device 3A includes carrier gas supply devices 11 and 12, a sample tank 20, a switching module M3, columns 41 and 42, and a detection device 50. Three microvalves V1 to V3 are mounted on the switching module M3. The configuration of the gas flow path switching device 1 according to the first embodiment described above is applied to the switching section including the microvalves V2 and V3 in the analytical device 3A of FIG. 10.

[0073] 11 and 12 are diagrams showing operation patterns A to I of the analytical device 3A. In operation pattern A (initial state), microvalves V1 to V3 are opened. Furthermore, pressure P1 is controlled to a value greater than pressure P2. As a result, the first carrier gas output from the AFC 11 passes through columns 41 and 42 and is supplied to the detection device 50, and the second carrier gas output from the APC 12 also passes through column 42 and is supplied to the detection device 50.

[0074] In the next operation pattern B, the sample gas in the sample tank 20 is injected into the column 41, and primary separation of the sample gas is performed. In the next operation pattern C, the component S1 is eluted from the column 41 and moves toward the column 42.

[0075] Thereafter, the operation pattern of the analyzer 3A is switched to the next operation pattern D. In operation pattern D, microvalve V3 is opened, and microvalves V1 and V2 are closed. As a result, component S1 is supplied to column 42 by the second carrier gas output from APC 12 and subjected to secondary separation, while components S2 and S3 remain in column 41.

[0076] Thereafter, the operation pattern of the analyzer 3A is switched to the next operation pattern E. In operation pattern E, microvalves V1 to V3 are opened, causing component S1 to elute from column 42 and be detected by detector 51, and component S2 to elute from column 41 and move toward column 42.

[0077] Thereafter, the operation pattern of the analyzer 3A is switched to the next operation pattern F. In operation pattern F, microvalve V3 is opened, and microvalves V1 and V2 are closed. As a result, component S1 is eluted from column 42 and detected by detection device 50, component S2 moves toward column 42, while component S3 remains in column 41. In the next operation pattern G, component S2 is supplied to column 42 and undergoes secondary separation.

[0078] Thereafter, the operation pattern of the analyzer 3 is switched to the next operation pattern H (backflush). In operation pattern H, microvalves V1 to V3 are opened, and pressure P1 is reduced to a value smaller than pressure P2. This reverses the flow direction of the carrier gas in column 41. In the next operation pattern I, component S3 is discharged from a vent (not shown).

[0079] As described above, the gas analyzer 2A according to Modification 1 also employs the configuration of the gas flow path switching device 1 according to the above-described Embodiment 1 as the configuration of the gas flow path switching mechanism, thereby making it possible to prevent carryover and contamination caused by flow path switching.

[0080] 13 is a diagram schematically illustrating an example of the overall configuration of a gas analyzer 2B according to Modification 2. In the gas analyzer 2B, the analyzer 3 of the gas analyzer 2 described above is changed to an analyzer 3B.

[0081] The analytical apparatus 3B includes carrier gas supply devices 11 and 12, a sample tank 20, a switching module M4, columns 41 and 42, and detection devices 51 and 52. Two microvalves V1 and V2 are mounted on the switching module M4. The configuration of the gas flow path switching device 1 according to the first embodiment described above is applied to the switching unit including the microvalves V1 and V2 in the analytical apparatus 3B of FIG. 10.

[0082] 14 shows operation patterns A to C of the analytical device 3B. In operation pattern A, microvalve V1 is opened and microvalve V2 is closed. This causes the sample gas to be injected into column 41, where primary separation of the sample gas is performed. Component S1 then elutes from column 41 and moves toward detector 51.

[0083] Thereafter, the operation pattern of the analyzer 3B is switched to the next operation pattern B. In operation pattern B, microvalve V1 is closed and microvalve V2 is opened. As a result, component S1 is supplied to the detector 51 by the second carrier gas from the APC 12 and detected, and component S2 is eluted from the column 42 and moves toward the column 42, where it is subjected to secondary separation.

[0084] Thereafter, the operation pattern of the analyzer 3B is switched to the next operation pattern C. In operation pattern C, microvalve V1 is opened and microvalve V2 is closed, thereby supplying component S2 to the detector 52 for detection, and component S3 is eluted from the column 41 and supplied to the detector 51 for detection.

[0085] As described above, the gas analyzer 2B according to Modification 2 also employs the configuration of the gas flow path switching device 1 according to the above-described embodiment 1 as the configuration of the gas flow path switching mechanism, thereby making it possible to prevent carryover and contamination caused by flow path switching.

[0086] [Aspects] It will be understood by those skilled in the art that the above-described embodiments and their modifications are specific examples of the following aspects.

[0087] (Item 1) A gas analyzer according to the present disclosure includes an inlet for a sample gas, an analysis unit that analyzes gas components contained in the sample gas, a flow path provided between the inlet and the analysis unit and having a branching portion, and a gas flow path switching unit provided at the branching portion of the flow path. The gas flow path switching unit includes a flow path plate having a first main surface and a second main surface opposite to the first main surface, with a first flow path, a second flow path, and a third flow path formed between the first and second main surfaces, a first valve disposed on the first main surface and configured to switch between connecting and disconnecting the first flow path and the second flow path, and a second valve disposed on the second main surface and configured to switch between connecting and disconnecting the first flow path and the third flow path.

[0088] According to the gas flow path switching device described in paragraph 1, the first valve and the second valve are respectively arranged on both sides (first main surface and second main surface) of the flow path plate. Therefore, compared to when the first valve and the second valve are arranged side by side on one side of the flow path plate, the dead volume during flow path switching by the first valve and the second valve can be made smaller. As a result, carryover and contamination during flow path switching can be suppressed.

[0089] (2) In the gas analyzer according to the first aspect, the first valve and the second valve overlap each other entirely or partially when viewed from the normal direction of the flow path plate.

[0090] According to the gas analyzer described in paragraph 2, the first valve and the second valve are disposed on both sides of the flow path plate, respectively, and also overlap each other completely or partially when viewed from the normal direction of the flow path plate, thereby making it possible to reduce the dead volume extending along the main surface of the flow path plate compared to when the first valve and the second valve do not overlap at all when viewed from the normal direction of the flow path plate.

[0091] (Item 3) In the gas analyzer described in item 2, the flow path plate has a first communication passage extending from an end of the first flow path toward the first main surface along a normal to the flow path plate, a second communication passage extending from an end of the second flow path toward the first main surface along a normal to the flow path plate, a third communication passage extending from the end of the first flow path toward the second main surface along a normal to the flow path plate, and a fourth communication passage extending from the end of the third flow path toward the second main surface along a normal to the flow path plate. The first valve is connected to the first and second communication passages in the flow path plate and is configured to be able to switch between connecting and disconnecting the first and second communication passages. The second valve is connected to the third and fourth communication passages in the flow path plate and is configured to be able to switch between connecting and disconnecting the third and fourth communication passages.

[0092] According to the gas analyzer described in paragraph 3, the first valve can be used to switch between communication and blocking between the first and second communication passages in the flow passage plate, thereby enabling switching between communication and blocking between the first and second flow passages. The second valve can be used to switch between communication and blocking between the third and fourth communication passages in the flow passage plate, thereby enabling switching between communication and blocking between the first and third flow passages.

[0093] (4) In the gas analyzer described in paragraph 3, the first valve has a first base portion having a first opening connected to the first communication passage of the flow path plate and a second opening connected to the second communication passage of the flow path plate, and a first diaphragm portion disposed opposite the first base portion and elastically deforming to switch between communication between the first opening and the second opening of the first base portion. The second valve has a second base portion having a third opening connected to the third communication passage of the flow path plate and a fourth opening connected to the fourth communication passage of the flow path plate, and a second diaphragm portion disposed opposite the second base portion and elastically deforming to switch between communication between the third opening and the fourth opening of the second base portion.

[0094] According to the gas analyzer described in item 4, the dead volume inside the valve can be made extremely small.

[0095] (Item 5) The gas analyzer according to item 1 further includes a first column and a second column, each of which separates gas components contained in the sample gas, and a connecting pipe fluidly connecting the first column and the second column. The gas flow path switching device is disposed in the connecting pipe.

[0096] (Item 6) In the gas analyzer according to item 5, the second column is a column for secondary separation that further separates the various components of the sample gas that have been primarily separated by the first column.

[0097] According to the gas analyzers described in the fifth and sixth aspects, carryover and contamination can be suppressed when switching the flow path of the connecting pipe that fluidly connects the first column and the second column.

[0098] (Clause 7) A gas flow path switching device according to the present disclosure is a gas flow path switching device for switching gas flow paths, and includes: a flow path plate having a first main surface and a second main surface opposite to the first main surface, with a first flow path, a second flow path, and a third flow path formed between the first main surface and the second main surface; a first valve disposed on the first main surface and configured to be able to switch between connecting and blocking the first flow path and the second flow path; and a second valve disposed on the second main surface and configured to be able to switch between connecting and blocking the first flow path and the third flow path.

[0099] According to the gas flow path switching device described in paragraph 7, the first valve and the second valve are respectively arranged on both sides (first main surface and second main surface) of the flow path plate, which makes it possible to reduce the dead volume during flow path switching by the first valve and the second valve compared to when the first valve and the second valve are arranged side by side on one side of the flow path plate.

[0100] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is defined by the claims, not by the description of the above embodiments, and is intended to include all modifications within the meaning and scope of the claims.

[0101] 1 Gas flow path switching device, 1A, 1B, 1C, 1D Switching unit, 2, 2A, 2B Gas analyzer, 3, 3A, 3B Analytical device, 11, 12 Carrier gas supply device, 20 Sample tank, 41, 42 Column, 43, 44 Loop, 45 Restrictor, 50, 51, 52 Detection device, 60 Input device, 70 Display device, 80 Drive device, 100 Control device, 110 Calculation unit, 120 Memory unit, 201 First microvalve, 202 Second microvalve, 220 Base layer, 221 Recess, 223, 224 Opening, 225 Bottom, 230 Diaphragm layer, 233 Flexible part, 234 Rigid part, 235 Fluid space, 240 Cover layer, 250 Flow path plate, 250a Upper surface, 250b Lower surface, 260 First plate, 261 to 265, 274, 275 communication passage, 270 second plate, 271 first flow path, 272 second flow path, 273 third flow path, DV1, DV2 dead volume, M1 to M4 switching module, V1 to V4, V6 to V9 microvalves, Y1, Y2 branch path.

Claims

1. A gas analyzer comprising an introduction part for a sample gas, an analysis part for analyzing gas components contained in the sample gas, a flow path provided between the introduction part and the analysis part and having a branch part, and a gas flow path switching part provided at the branch part of the flow path, the gas flow path switching part including a flow path plate having a first main surface and a second main surface opposite to the first main surface, and a first flow path, a second flow path, and a third flow path formed between the first main surface and the second main surface, a first valve disposed on the first main surface and configured to be able to switch between communication and interruption between the first flow path and the second flow path, and a second valve disposed on the second main surface and configured to be able to switch between communication and interruption between the first flow path and the third flow path.

2. The gas analyzer according to claim 1, wherein when viewed from the normal direction of the flow path plate, all or part of the first valve and the second valve overlap each other.

3. The flow path plate has a first communication path extending from an end of the first flow path toward the first main surface along the normal direction of the flow path plate, a second communication path extending from an end of the second flow path toward the first main surface along the normal direction of the flow path plate, a third communication path extending from an end of the first flow path toward the second main surface along the normal direction of the flow path plate, and a fourth communication path extending from an end of the third flow path toward the second main surface along the normal direction of the flow path plate. The first valve is connected to the first communication path and the second communication path of the flow path plate and is configured to be able to switch between communication and interruption between the first communication path and the second communication path. The second valve is connected to the third communication path and the fourth communication path of the flow path plate and is configured to be able to switch between communication and interruption between the third communication path and the fourth communication path. The gas analyzer according to claim 2.

4. The first valve has a first base portion formed with a first opening connected to the first communication passage of the flow path plate and a second opening connected to the second communication passage of the flow path plate, and a first diaphragm portion disposed opposite to the first base portion and configured to switch between communication and interruption between the first opening and the second opening of the first base portion by elastic deformation. The second valve has a second base portion formed with a third opening connected to the third communication passage of the flow path plate and a fourth opening connected to the fourth communication passage of the flow path plate, and a second diaphragm portion disposed opposite to the second base portion and configured to switch between communication and interruption between the third opening and the fourth opening of the second base portion by elastic deformation. The gas analyzer according to claim 3.

5. The gas analyzer further includes a first column and a second column for separating each gas component contained in the sample gas, and a connection pipe for fluidly connecting the first column and the second column. The gas flow path switching unit is disposed in the connection pipe. The gas analyzer according to claim 1.

6. The second column is a column for secondary separation that further separates various components of the sample gas primarily separated by the first column. The gas analyzer according to claim 5.

7. A gas flow path switching device for switching a gas flow path, comprising: a flow path plate having a first main surface and a second main surface opposite to the first main surface, and a first flow path, a second flow path, and a third flow path formed between the first main surface and the second main surface; a first valve disposed on the first main surface and configured to be able to switch between communication and interruption between the first flow path and the second flow path; and a second valve disposed on the second main surface and configured to be able to switch between communication and interruption between the first flow path and the third flow path. A gas flow path switching device.

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