JP2011013028A - Fluorescent x-ray analyzer and fluorescent x-ray analysis method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fluorescent X-ray analyzer utilizing a plurality of kinds of gases as gases for adjusting an atmosphere, and also to provide a fluorescent X-ray analyzing method.SOLUTION: In the fluorescent X-ray analyzer, the atmosphere in a measuring chamber (internal space) 31, through which the primary X rays from an X-ray tube (X-ray irradiation part) 51 and the fluorescent X rays detected by an X-ray detector (detection part) 52 pass, is set to a specific gas atmosphere before fluorescent X-ray analysis is performed. A helium pressure adjuster 21 and a nitrogen pressure adjuster 22 are provided on the way of piping 1 for supplying gas to the measuring chamber 31 in parallel. The respective pressure adjusters are adjusted to the pressure corresponding to the kind of the gas and, when the gas is supplied to the measuring chamber 31, the route of the gas is changed over by a changeover valve (route changing-over means) 26 so as to pass through the pressure adjuster corresponding to the kind of the gas. A plurality of kinds of gases are used as gases for adjusting the atmosphere while using almost all of the parts of the piping 1 in common.

Description

  The present invention relates to a fluorescent X-ray analyzer, and more particularly to a fluorescent X-ray analyzer and a fluorescent X-ray analysis method for performing measurement in an atmosphere of a specific gas such as helium.

  X-ray fluorescence analysis is an analysis technique in which primary X-rays are irradiated onto a sample, fluorescent X-rays generated from the sample are detected, and qualitative analysis or quantitative analysis of elements contained in the sample is performed from the fluorescent X-ray spectrum. . An X-ray fluorescence analyzer that performs X-ray fluorescence analysis includes an X-ray tube that generates primary X-rays, an X-ray detector that uses a semiconductor detector or a proportional counter, and the wavelength of X-rays detected by the X-ray detector It consists of an analyzer that analyzes the distribution or energy distribution. When performing fluorescent X-ray analysis, the sample is irradiated with primary X-rays generated by an X-ray tube, and X-ray detectors detect fluorescent X-rays generated from the sample irradiated with the primary X-rays. The X-ray spectrum is analyzed with an analyzer. Patent Document 1 describes an X-ray fluorescence analyzer that performs X-ray fluorescence analysis of a liquid or powder sample.

  When analyzing light elements in a sample in fluorescent X-ray analysis, the fluorescent X-rays from the light elements are easily absorbed in the air, and the fluorescent X-ray spectrum of the light elements shows the fluorescence X from the elements in the air. Since the spectrum of the line is superimposed, it is difficult to perform analysis with high accuracy. Therefore, in the conventional X-ray fluorescence analyzer, in order to perform X-ray fluorescence analysis of light elements, the air in the measurement chamber provided with the X-ray tube and the X-ray detector is replaced with helium gas. Irradiation of a primary X-ray sample and detection of fluorescent X-rays were performed in an atmosphere. In the helium gas atmosphere, X-ray absorption is small and the X-ray spectrum superimposed on the light element fluorescence X-ray spectrum is difficult to generate. By performing the above, it is possible to accurately perform a fluorescent X-ray analysis of light elements.

Japanese Patent Laid-Open No. 9-127028

  As described above, when X-ray fluorescence analysis of light elements is performed, it is common to perform irradiation with primary X-rays and detection of fluorescent X-rays in an atmosphere of helium gas. However, since helium gas is expensive and facilities for supplying helium gas are limited, it is possible to perform light element fluorescent X-ray analysis more easily by using gas that is cheaper and easier to supply. There is a need to want. For example, nitrogen gas is cheaper than helium gas, and facilities for supplying nitrogen gas are widely used. Therefore, by using nitrogen gas instead of helium gas, light element fluorescent X-rays can be easily used. Analysis can be performed. In fact, when primary X-ray irradiation and fluorescent X-ray detection are performed in an atmosphere of nitrogen gas, light X-ray fluorescence analysis of light elements is performed with sufficient accuracy, although it is inferior to the case of using helium gas. be able to.

  However, since helium gas and other gases such as nitrogen gas have different viscosities, even if the gas is supplied under the same conditions, the gas flow rate per unit time is different. For example, since nitrogen gas has a viscosity higher than that of helium gas, the flow rate of nitrogen gas per unit time is smaller when supplied at the same pressure using pipes having the same diameter. When the flow rate of gas per unit time is small, the air cannot be sufficiently replaced, so that the fluorescent X-ray analysis cannot be performed with high accuracy. Therefore, once a gas supply mechanism such as a pipe for supplying gas into the measurement chamber of the fluorescent X-ray analyzer is provided, only a specific gas corresponding to the provided gas supply mechanism can be used. For this reason, the conventional X-ray fluorescence analyzer has a problem that a plurality of gases cannot be used as the atmosphere adjusting gas. For example, the gas cannot be properly used depending on the sample or the required accuracy. When a plurality of gas supply mechanisms are provided in the fluorescent X-ray analyzer, such as a gas supply mechanism for supplying helium gas and a gas supply mechanism for supplying nitrogen gas, etc., a plurality of gases can be used. There is a problem that the configuration of the fluorescent X-ray analyzer becomes complicated and the cost increases.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a fluorescent X-ray analyzer and a fluorescent device capable of using a plurality of types of gases as atmosphere adjusting gas with a simple configuration. It is to provide an X-ray analysis method.

  An X-ray fluorescence analyzer according to the present invention includes an X-ray irradiation unit that irradiates a sample with primary X-rays, a detection unit that detects fluorescent X-rays generated from the sample by irradiation with primary X-rays, and the X-ray irradiation unit A specific gas atmosphere including an internal space including at least a space through which the primary X-rays generated from the sample pass before being irradiated to the sample and a space through which the fluorescent X-rays generated from the sample enter the detection unit. In the fluorescent X-ray analyzer for performing fluorescent X-ray analysis, a plurality of pipes for supplying gas to the internal space, a plurality of pressure regulators provided in parallel in the pipe, Path switching means for selectively switching the path of the gas supplied to the internal space from the paths passing through the pressure regulator, and each of the plurality of pressure regulators is a gas supplied to the internal space The pressure of multiple types of gas Characterized in that the people in the pressure corresponding to is arranged to adjust.

  In the present invention, an X-ray fluorescence analyzer for performing X-ray fluorescence analysis using an internal space including a space through which primary X-rays and fluorescent X-rays pass as an atmosphere of a specific gas is provided in a pipe for supplying gas to the internal space. In the middle, a plurality of pressure regulators are provided in parallel, and each pressure regulator regulates the pressure of the gas to a pressure corresponding to each of the plurality of types of gas, and the gas path is any pressure regulator. You can switch between passing. By switching the pressure regulator through which the gas passes according to the type of gas, the gas can be supplied to the internal space at a pressure according to the type of gas.

  In the fluorescent X-ray analysis apparatus according to the present invention, each of the plurality of pressure regulators has a predetermined common flow rate that does not depend on the type of gas, and the flow rate per unit time of the gas supplied to the internal space through the pipe. It is configured to have a flow rate.

  In the present invention, each pressure regulator of the X-ray fluorescence analyzer is configured so that the flow rate per unit time of the gas supplied to the internal space is a common flow rate that does not depend on the gas type, depending on the type of gas. Is set. As a result, regardless of which gas is used, the gas is supplied to the internal space at the same flow rate per unit time.

  The X-ray fluorescence analyzer according to the present invention further includes a flow rate adjusting means for adjusting a flow rate per unit time of the gas supplied to the internal space to one of two predetermined flow rates. .

  In the fluorescent X-ray analyzer according to the present invention, the pipe is branched into two branch pipes having different flow rates per unit time of the flowing gas, and both the two branch pipes are connected to the internal space. The flow rate adjusting means is an on-off valve that closes and opens a branch pipe having a relatively high flow rate per unit time of gas in the two branch pipes.

  The fluorescent X-ray analysis method according to the present invention is the method of performing fluorescent X-ray analysis of a sample using the fluorescent X-ray analyzer according to the present invention, wherein the type of gas supplied to the internal space is supplied to the path switching means. The gas path is switched so that the gas passes through the corresponding pressure regulator, and the flow rate adjusting means allows the flow rate per unit time of the gas supplied to the internal space to be a large flow rate of the two flow rates. After the gas flow to the internal space is continued for a predetermined time, the flow rate adjusting means controls the flow rate per unit time of the gas to be supplied to the internal space. The flow rate per unit time of the gas supplied to the internal space is adjusted to the smaller flow rate of the two stages, and the fluorescent X-ray analysis is started. It is characterized by doing.

  In the present invention, the pipe for supplying gas to the internal space of the fluorescent X-ray analyzer branches into two branch pipes having different flow rates per unit time, both of the branch pipes are connected to the internal space, and the flow rate is further increased. The flow rate per unit time of the gas supplied to the internal space is adjusted in two stages by opening and closing the branch pipe with the larger flow rate with an on-off valve. When performing fluorescent X-ray analysis, gas is supplied to the internal space at a large flow rate, and after adjusting the gas flow rate to a small flow rate, the fluorescent X-ray analysis is started. First, by supplying gas to the internal space at a large flow rate, the air in the internal space is replaced with gas quickly and reliably. After the air is replaced with gas, the gas atmosphere is maintained even if the flow rate per unit time of the gas is reduced.

  In the present invention, since the viscosities are different from each other, a plurality of types of gases having different pressures necessary for supply can be supplied to the internal space of the fluorescent X-ray analyzer using the same pipe. Therefore, it is possible to use a plurality of types of gases as gases for adjusting the atmosphere of the internal space, and it is possible to use different gases according to the sample or the required accuracy. In addition, when using any of multiple types of gas, most of the piping can be used in common except for the pressure regulator, so that the increase in the cost of the fluorescent X-ray analyzer can be minimized. Can do.

  Further, in the present invention, regardless of which gas is used, the gas is supplied to the internal space of the fluorescent X-ray analyzer at the same flow rate per unit time. However, the flow rate of the gas does not fluctuate, and it is possible to execute the fluorescent X-ray analysis stably even when any gas is used.

  In the present invention, the gas is first supplied to the internal space at a large flow rate, so that the air in the internal space is surely replaced with the gas, and the gas flow rate is adjusted to a small flow rate before the fluorescent X By performing the line analysis, the present invention has excellent effects such as improving the accuracy of the fluorescent X-ray analysis and suppressing the consumption of the gas for adjusting the atmosphere.

It is a block diagram which shows the structure of the fluorescent X-ray-analysis apparatus which concerns on Embodiment 1 of this invention. It is a flowchart which shows the procedure of the fluorescent X ray analysis method of this invention. It is a schematic diagram which shows the flow of helium gas at the time of performing a fluorescent X ray analysis. It is a schematic diagram which shows the flow of the nitrogen gas at the time of performing a fluorescent X ray analysis. It is a block diagram which shows the structure of the fluorescent X-ray-analysis apparatus which concerns on Embodiment 2 of this invention.

Hereinafter, the present invention will be specifically described with reference to the drawings showing embodiments thereof.
(Embodiment 1)
FIG. 1 is a block diagram showing a configuration of a fluorescent X-ray analysis apparatus according to Embodiment 1 of the present invention. The X-ray fluorescence analyzer includes a housing 3 formed in a box shape with a material that shields X-rays, and a hollow measurement chamber 31 is formed inside the housing 3. A through hole 34 connected to the measurement chamber 31 is formed in a part of the upper surface of the housing 3, and the fluorescent X-ray analysis apparatus covers at least a part of the upper surface of the housing 3 including the through hole 34. 43. Between the lid portion 43 and the upper surface of the housing 3, a sample chamber 44 that is a space for arranging the sample cell 41 that holds the sample is formed. The lid 43 is configured to be openable and closable with respect to the housing 3 in order to put the sample cell 41 into and out of the sample chamber 44.

  The sample cell 41 is a cell for holding a fluid sample such as powder or liquid, and is formed in a cup shape. The diameter of the opening of the sample cell 41 formed in a cup shape is larger than the diameter of the through hole 34 formed in the housing 3. A sample to be subjected to fluorescent X-ray analysis is filled in a cup-shaped sample cell 41, and the opening of the sample cell 41 is sealed with an X-ray transmission film 42 such as a polyester sheet that transmits X-rays. The sample cell 41 is arranged at a position where the through hole 34 is formed in the upper surface of the housing 3 with the opening sealed by the X-ray permeable film 42 on the lower side. By disposing the sample cell 41, the through hole 34 is blocked.

  Further, the X-ray fluorescence analyzer includes an X-ray tube (X-ray irradiation unit) 51 and an X-ray detector (detection unit) 52 that emit primary X-rays in the measurement chamber 31. The X-ray tube 51 is disposed at a position where primary X-rays are emitted toward the through hole 34. When performing fluorescent X-ray analysis, since the sample cell 41 is disposed at the position of the through hole 34, the primary X-ray generated from the X-ray tube 51 passes through the X-ray transmission film 42 and passes through the sample cell 41. The sample inside is irradiated. The sample in the sample cell 41 irradiated with the primary X-rays generates fluorescent X-rays, and the fluorescent X-rays pass through the X-ray transmission film 42 and are emitted into the measurement chamber 31. The X-ray detector 52 is disposed at a position for detecting fluorescent X-rays generated from the sample in the sample cell 41. The path through which the primary X-rays irradiated by the X-ray tube 51 and the fluorescent X-rays detected by the X-ray detector 52 pass is indicated by broken line arrows in FIG. As shown in FIG. 1, the space through which the sample is irradiated with the primary X-ray from the X-ray tube 51 and the space through which the fluorescent X-ray generated from the sample enters the X-ray detector 52. Are included in the measurement chamber 31. Therefore, the measurement chamber 31 corresponds to the internal space in the present invention.

  An openable / closable shutter (not shown) is provided at the radiation port for emitting the primary X-rays of the X-ray tube 51. The X-ray tube 51 is configured to always generate X-rays in order to stabilize the output of the primary X-rays. When the shutter is opened, the X-ray tube 51 transmits the primary X-rays in the measurement chamber 31. Radiates to. The X-ray detector 52 has a configuration using a proportional counter as a detection element, and outputs an electrical signal proportional to the energy of fluorescent X-rays incident on the proportional counter. The X-ray detector 52 may have a form using a detection element other than a proportional counter, such as a semiconductor detection element, as the detection element. The X-ray detector 52 is connected to an analysis unit 53 that analyzes the output electric signal. The analysis unit 53 receives the electrical signal output from the X-ray detector 52, counts the intensity and the number of each electrical signal corresponding to the energy of the fluorescent X-ray, and the relationship between the fluorescent X-ray energy and the count number, That is, a process of acquiring a fluorescent X-ray spectrum is performed. The analysis unit 53 may be configured to further perform qualitative analysis or quantitative analysis of an element that has generated fluorescent X-rays based on the acquired fluorescent X-ray spectrum. A controller 54 that controls the operation of the X-ray tube 51 and the analyzer 53 is connected to the X-ray tube 51 and the analyzer 53. The control unit 54 is connected to an input unit 55 such as a keyboard or a touch panel through which various instructions are input by a user's operation, and an output unit 56 such as a display or a printer that outputs analysis results.

  The X-ray fluorescence analyzer of the present invention is configured to replace the air in the measurement chamber 31 with two kinds of gases. In the present embodiment, a mode in which helium gas and nitrogen gas are used as atmosphere adjusting gases is shown. A supply port 32 for supplying a gas, which is helium gas or nitrogen gas, to the measurement chamber 31 is formed in the housing 3, and a portion covered by the lid portion 43 of the housing 3 has a measurement chamber 31. An inflow port 33 for allowing gas to flow into the sample chamber 44 is formed. Gas is supplied from the outside of the housing 3 to the measurement chamber 31 through the supply port 32, and flows into the sample chamber 44 from the measurement chamber 31 through the inflow port 33, whereby the inside of the measurement chamber 31 and the sample chamber 44. The air is replaced with gas, and a gas atmosphere is obtained. The casing 3 and the lid 43 are formed with an outlet (not shown) through which air flows out. Note that the housing 3 and the lid 43 may have a configuration in which a special outlet is not provided by providing a gap through which air can flow out.

  A pipe 1 connected to a gas supply source 6 of helium gas or nitrogen gas is connected to the supply port 32. The gas supply source 6 is a gas cylinder, a gas generator, a gas supply pipe, or the like. Helium gas or nitrogen gas is supplied to the measurement chamber 31 via the pipe 1. An on-off valve 25 is provided in the middle of the pipe 1, and the on-off valve 25 starts and stops supplying gas from the gas supply source 6 by opening and closing. On the downstream side of the on-off valve 25, the pipe 1 is branched into a branch pipe 11 and a branch pipe 12. A helium pressure regulator 21 is provided in the middle of the branch pipe 11, and a nitrogen pressure regulator 22 is provided in the middle of the branch pipe 12.

  The branch pipe 11 is a pipe through which helium gas passes when helium gas is used as the atmosphere adjusting gas, and the branch pipe 12 allows nitrogen gas to pass through when nitrogen gas is used as the atmosphere adjusting gas. It is a tube. The helium pressure regulator 21 is set to adjust the pressure of the helium gas to a specific pressure predetermined for the helium gas, and the nitrogen pressure regulator 22 is preset for the nitrogen gas. It is preset to adjust the pressure of nitrogen gas to a specified specific pressure. Specifically, the helium pressure regulator 21 and the nitrogen pressure regulator 22 are set so that the flow rates per unit time of the helium gas and the nitrogen gas supplied to the measurement chamber 31 and the sample chamber 44 are the same. . Since nitrogen gas is more viscous than helium gas, it is necessary to increase the pressure of the nitrogen gas in order to make the flow rates of helium gas and nitrogen gas per unit time the same. For example, the pressure regulator 21 for helium is set to a pressure of 20 kPa, and the pressure regulator 22 for nitrogen is set to a pressure of 80 kPa.

  The branch pipe 11 and the branch pipe 12 are joined via a switching valve 26. The switching valve 26 has a function of closing one of the branch pipe 11 and the branch pipe 12 and opening the other, and can switch which of the branch pipe 11 and the branch pipe 12 is opened. When helium gas is used as the atmosphere adjusting gas, the switching valve 26 opens the branch pipe 11 and closes the branch pipe 12, and when nitrogen gas is used as the atmosphere adjusting gas, the switching valve 26 is The branch pipe 12 is opened and the branch pipe 11 is closed. In this way, the switching valve 26 functions as a path switching means in the present invention.

  Further, on the downstream side of the switching valve 26, the pipe 1 is branched into a branch pipe 13 and a branch pipe 14. A flow rate adjusting on / off valve 27 and a large flow rate capillary 23 are provided in the middle of the branch pipe 13, and a small flow rate capillary 24 is provided in the middle of the branch pipe 14. The large flow rate capillary 23 and the small flow rate capillary 24 are tubes whose sizes and shapes are adjusted so that a gas having a constant pressure passes at a constant flow rate per unit time. Defines the flow rate of gas passing through per unit time. The large flow rate capillary 23 is formed so that the gas flows at a flow rate per unit time larger than that of the small flow rate capillary 24. For this reason, the flow rate of the gas flowing through the branch pipe 13 is larger than that of the branch pipe 14. The helium pressure regulator 21 and the nitrogen pressure regulator 22 have a large flow rate capillary regardless of whether helium gas or nitrogen gas flows, depending on the size and shape of the large flow rate capillary 23 and the small flow rate capillary 24. The gas pressure is set in advance so that the flow rates per unit time of the gas flowing through the small flow rate capillary 23 and the small flow rate capillary 24 are the same. For example, the large flow rate capillary 23 is formed so that the flow rate of gas per unit time is 0.9 L / min, and the small flow rate capillary 24 is formed so that the flow rate of gas per unit time is 0.1 L / min. Has been. Actually, the pressure settings in the helium pressure regulator 21 and the nitrogen pressure regulator 22 are adjusted so that the flow rate per unit time in the large flow rate capillary 23 and the small flow rate capillary 24 becomes a specific value. The

  The flow rate adjusting on-off valve 27 opens and closes the branch pipe 13 by opening and closing. The branch pipe 13 and the branch pipe 14 merge, and the pipe 1 where the branch pipe 13 and the branch pipe 14 merge is connected to the supply port 32. When the flow control valve 27 opens the branch pipe 13, the gas passes through both the branch pipe 13 and the branch pipe 14 and is supplied from the supply port 32 to the measurement chamber 31. In this case, the flow rate per unit time of the gas supplied to the measurement chamber 31 is the sum of the flow rates per unit time defined by the large flow rate capillary 23 and the small flow rate capillary 24. When the flow regulating valve 27 closes the branch pipe 13, the gas passes only through the branch pipe 14 and is supplied to the measurement chamber 31. In this case, the flow rate per unit time of the gas supplied to the measurement chamber 31 is the flow rate per unit time defined by the small flow rate capillary 24, compared with the case where the flow rate adjusting on / off valve 27 opens the branch pipe 13. Small flow rate. Thus, the flow rate adjusting on-off valve 27 can adjust the flow rate per unit time of the gas to one of two flow rates by opening and closing, and functions as a flow rate adjusting means in the present invention.

  The on-off valve 25, the switching valve 26, and the flow rate adjusting on-off valve 27 are electromagnetic valves, and are configured to be controlled by the control unit 54. The pipe 1 is appropriately provided with a relief valve, a flow meter, and a pressure gauge (not shown).

  Next, the fluorescent X-ray analysis method of the present invention using the fluorescent X-ray analyzer configured as described above will be described. FIG. 2 is a flowchart showing the procedure of the fluorescent X-ray analysis method of the present invention. FIG. 3 is a schematic diagram showing the flow of helium gas when performing fluorescent X-ray analysis. In FIG. 3, the gas flow is indicated by a thick arrow. When performing fluorescent X-ray analysis, the user first fills the sample cell 41 with the sample and seals the opening of the sample cell 41 with the X-ray transmission film 42. Next, the user opens the lid 43, and places the sample cell 41 at the position of the through hole 34 of the housing 3 with the opening sealed with the X-ray permeable film 42 on the lower side. 43 is closed. The X-ray fluorescence analyzer includes a sensor (not shown) that detects whether or not the lid 43 is closed. When the lid 43 is not closed, the shutter of the radiation port of the X-ray tube 51 is closed. In this configuration, the start of fluorescent X-ray analysis is prohibited. When the lid 43 is closed, the shutter is opened, and primary X-rays from the X-ray tube 51 are emitted into the measurement chamber 31.

  The X-ray fluorescence analyzer in which the sample cell 41 is placed and the lid 43 is closed is used to adjust the atmosphere in the measurement chamber 31 and the sample chamber 44 by the user operating the input unit 55. The setting of the type of gas to be received is received by the input unit 55 (S1). Next, the control unit 54 switches the switching valve 26 so as to open the branch pipe provided with the pressure regulator corresponding to the gas type in accordance with the received gas type setting (S2). For example, accepting setting of helium gas as the gas type, the control unit 54 switches the switching valve 26 so as to open the branch pipe 11 and close the branch pipe 12. FIG. 3A shows the state in step S2 when helium gas is used. The switching valve 26 opens the branch pipe 11 and closes the branch pipe 12, and the open / close valve 25 is closed at this stage. Note that when the switching valve 26 is switched in advance according to the type of gas, steps S1 and S2 may be omitted.

  Next, the fluorescent X-ray analysis apparatus accepts an analysis start instruction by the input unit 55 when the user operates the input unit 55 (S3), and the control unit 54 includes the on-off valve 25 and the on-off valve for flow rate adjustment. 27 is released (S4). The flow rate adjusting on / off valve 27 may be opened in advance before the analysis is started. FIG. 3B shows a state when step S4 is executed. When the on-off valve 25 is opened, helium gas is supplied from the gas supply source 6 to the measurement chamber 31 through the pipe 1. Since the branch pipe 12 is closed by the switching valve 26 and the branch pipe 11 is opened, the helium gas passes through the branch pipe 11. When the helium gas passes through the branch pipe 11, the pressure of the helium gas is adjusted to a predetermined pressure by the helium pressure regulator 21. Further, since the flow rate adjusting on-off valve 27 is opened, the helium gas passes through both the branch pipe 13 and the branch pipe 14. Since the helium gas passes through both the large flow rate capillary 23 and the small flow rate capillary 24, the helium gas is supplied to the measurement chamber 31 at a flow rate per unit time that is the sum of the flow rates defined by the large flow rate capillary 23 and the small flow rate capillary 24. Is done. Since a large flow of helium gas is supplied into the measurement chamber 31 and further into the sample chamber 44, the air in the measurement chamber 31 and the sample chamber 44 is quickly replaced with helium gas. It becomes the atmosphere of.

  The controller 54 determines whether or not a predetermined time such as a predetermined 5 seconds has elapsed since the opening / closing valve 25 was opened (S5). When the predetermined time has not yet elapsed (S5: NO), the control unit 54 continues the determination. When a predetermined time has elapsed after opening the on-off valve 25 (SS5: YES), the control unit 54 closes the on-off valve 27 for flow rate adjustment (S6). FIG. 3C shows a state at the time when Step S6 is executed. By closing the flow rate adjusting on / off valve 27, helium gas cannot be passed through the branch pipe 13 but is supplied to the measurement chamber 31 through the branch pipe 14. Since the helium gas passes through only the small flow rate capillary 24 among the large flow rate capillary 23 and the small flow rate capillary 24, the helium gas is supplied to the measurement chamber 31 at a small flow rate per unit time defined by the small flow rate capillary 24. Is done.

  The control unit 54 adjusts the flow rate per unit time of the gas to a small flow rate by closing the flow rate adjusting on-off valve 27 in step S6 described above, and then detects and analyzes the fluorescent X-rays in the X-ray detector 52. By starting the analysis at 53, the fluorescent X-ray analysis is started (S7). In an atmosphere of helium gas, the X-ray tube 51 irradiates the sample with primary X-rays, and the X-ray detector 52 detects fluorescent X-rays from the sample. The analysis unit 53 analyzes the detection result. Next, the control unit 54 accepts an instruction to end the analysis by the user's operation at the input unit 55 or waits for timing for ending the fluorescent X-ray analysis due to elapse of a predetermined analysis time. (S8). If the end timing has not yet come (S8: NO), the control unit 54 continues the fluorescent X-ray analysis. When the end timing has come (S8: YES), the control unit 54 causes the output unit 56 to output an analysis result such as the detected spectrum of fluorescent X-rays (S9), and closes the on-off valve 25 (S10). Then, the fluorescent X-ray analysis process is terminated.

  In the example shown in FIG. 3, helium gas is used as the atmosphere adjusting gas. However, even when nitrogen gas is used, the fluorescent X-ray analysis can be performed in the same manner. is there. FIG. 4 is a schematic diagram showing the flow of nitrogen gas when performing fluorescent X-ray analysis. When nitrogen gas is used as the atmosphere adjustment gas, in step S1, the input unit 55 accepts the setting of nitrogen gas as the gas type, and in step S2, the control unit 54 opens the branch pipe 12 and opens the branch pipe. The switching valve 26 is switched so that 11 is closed. FIG. 4A shows the state when step S4 is executed, and FIG. 4B shows the state when step S6 is executed. The nitrogen gas passes through the branch pipe 12, is adjusted to a predetermined pressure by the nitrogen pressure regulator 22, and is supplied to the measurement chamber 31.

  As described above in detail, the X-ray fluorescence spectrometer of the present invention includes a plurality of pressure regulators in parallel in the middle of the pipe 1 for supplying gas to the measurement chamber 31, and each pressure regulator regulates the gas pressure. The pressure is adjusted according to each of a plurality of types of gas, and it is possible to switch which pressure regulator the gas path passes through. By switching the pressure regulator through which the gas passes according to the type of gas, it becomes possible to supply the gas to the measurement chamber 31 at a pressure according to the type of gas, and the viscosity is different from each other. A plurality of types of gases having different pressures can be supplied to the measurement chamber 31 using the same pipe. Therefore, in the fluorescent X-ray analysis apparatus of the present invention, it is possible to use a plurality of types of gases as gases for adjusting the atmosphere in the measurement chamber 31, and it is possible to use different gases depending on the sample or the required accuracy. It becomes possible. Further, in the present invention, a plurality of types of gas can be used with a simple configuration by providing a plurality of pressure regulators in parallel. Regardless of the type of gas used, most parts of the pipe 1 can be used in common except for the pressure regulator, so the configuration for using multiple types of gas is minimized, and fluorescence An increase in the cost of the X-ray analyzer can be minimized. In the present invention, each pressure regulator is configured so that the flow rate per unit time of the gas supplied to the measurement chamber 31 is the same regardless of the type of gas, depending on the size and shape of the piping and the type of gas. The pressure is set. Thereby, regardless of which gas is used, the gas is supplied to the measurement chamber 31 at the same flow rate per unit time. Even if the type of gas for adjusting the atmosphere is changed, the flow rate of the gas does not fluctuate, and it is possible to perform the fluorescent X-ray analysis stably even when any gas is used.

  In the present invention, the pipe 1 branches into the branch pipe 13 having the large flow rate capillary 23 and the branch pipe 14 having the small flow rate capillary 24, and finally joins and is connected to the supply port 32. . The X-ray fluorescence analyzer can adjust the flow rate per unit time of the gas supplied to the measurement chamber 31 in two stages by opening and closing the branch pipe 13 using the flow control valve 27. When performing fluorescent X-ray analysis, first, gas is supplied to the measurement chamber 31 at a large flow rate, and after adjusting the gas flow rate to a small flow rate, the fluorescent X-ray analysis is started. First, by supplying the gas to the measurement chamber 31 at a large flow rate, the air in the measurement chamber 31 is quickly and reliably replaced with the gas. Therefore, particularly in light element fluorescent X-ray analysis, fluorescent X-ray analysis is performed. Improves accuracy. Once the air in the measurement chamber 31 is replaced with gas, the gas atmosphere is maintained even if the flow rate of gas per unit time is reduced. Therefore, the fluorescent X-ray analysis is started by adjusting the gas flow rate to a smaller flow rate, and the fluorescent X-ray analysis is performed while supplying the gas to the measurement chamber 31 at a small flow rate. While maintaining the accuracy, the consumption of gas for adjusting the atmosphere can be suppressed.

  In the present embodiment, the gas is supplied to the measurement chamber 31 via the supply port 32, and the gas is supplied from the measurement chamber 31 to the sample chamber 44 via the inflow port 33. However, the X-ray fluorescence analyzer may be configured to supply gas from the pipe 1 to the measurement chamber 31 and the sample chamber 44 individually. Further, in the present embodiment, when supplying gas to the measurement chamber 31 at a large flow rate, a mode of supplying the gas that has passed through the large flow rate capillary 23 and the small flow rate capillary 24 has been described. Instead, the fluorescent X-ray analyzer may be configured to supply the gas that has passed only through the large flow capillary 23 when supplying the gas to the measurement chamber 31 at a large flow rate.

(Embodiment 2)
FIG. 5 is a block diagram showing the configuration of the X-ray fluorescence spectrometer according to Embodiment 2 of the present invention. In the second embodiment, the through hole 34 formed in the housing 3 is sealed with the X-ray transmissive film 35. By sealing the through hole 34 with the X-ray permeable film 35, it is possible to prevent the sample from being contaminated in the measurement chamber 31 even when the sample is spilled from the sample cell 41. In a state where the sample cell 41 is placed at the position of the through hole 34, a sealed space is formed between the X-ray transmissive film 35 that seals the through hole 34 and the X-ray transmissive film 42 that seals the opening of the sample cell 41. 37 is generated. In the present embodiment, in addition to the measurement chamber 31, this sealed space 37 also corresponds to the internal space in the present invention.

  A supply path 36 for supplying gas to the sealed space 37 is formed in the housing 3, and the pipe 1 is connected to the supply path 36. The branch pipe 13 and the branch pipe 14 branched in the middle of the pipe 1 merge, the pipe 1 further branches downstream from where the branch pipe 13 and the branch pipe 14 merge, and each of the branched pipes 1 is supplied to the supply port 32. It is connected to the path 36. In a state where the flow rate adjusting on-off valve 27 is open, the gas that has passed through the large flow rate capillary 23 and the small flow rate capillary 24 is supplied to the measurement chamber 31 at a high flow rate through the supply port 32 and supplied. It is supplied to the sealed space 37 at a large flow rate via the path 36. When the flow rate adjusting on / off valve 27 is closed, only the gas that has passed through the small flow rate capillary 24 is supplied to the measurement chamber 31 at a small flow rate via the supply port 32 and also via the supply path 36. And supplied to the sealed space 37 at a small flow rate.

  In the present embodiment, the fluorescent X-ray analyzer does not have the function of replacing the air in the sample chamber 46 with gas. The lid 45 only needs to have a function of protecting the sample cell 41 and a function of shielding leaked X-rays, and does not require sealing to maintain the atmosphere in the sample chamber 46. Other configurations of the X-ray fluorescence analyzer are the same as those of the first embodiment, and the corresponding parts are denoted by the same reference numerals and description thereof is omitted.

  Also in the present embodiment, it is possible to use a plurality of types of gases as the atmosphere adjustment gas by performing the same processing as in the first embodiment, and to the measurement chamber 31 and the sealed space 37. By adjusting the flow rate of the supplied gas per unit time in two stages, the consumption of the gas for adjusting the atmosphere can be suppressed while maintaining the accuracy of the fluorescent X-ray analysis. Furthermore, in the present embodiment, the gas in the space through which the primary X-rays and fluorescent X-rays pass is efficiently replaced by supplying gas individually to the measurement chamber 31 and the sealed space 37, and the sample chamber 44. In addition, compared with the first embodiment in which gas is supplied, it is possible to suppress the consumption of the gas for adjusting the atmosphere.

  In addition, in this Embodiment, although the form which supplies a gas separately to the measurement chamber 31 and the sealed space 37 was shown, it is not restricted to this, The fluorescent X-ray-analysis apparatus once supplied to the measurement chamber 31 The configuration may be such that the gas is supplied from the measurement chamber 31 to the sealed space 37. In the first and second embodiments, the on-off valve 25, the switching valve 26, and the flow rate adjusting on-off valve 27 are electromagnetic valves, and the operation is controlled by the control unit 54. However, the on-off valve 25, the switching valve 26, and the flow rate adjusting on-off valve 27 may be manually operated by the user.

  In the first and second embodiments, helium gas and nitrogen gas are used as the atmosphere adjusting gas. However, the present invention is not limited to this, and the present invention uses other gases as the atmosphere adjusting gas. The form to use may be sufficient. Moreover, in Embodiment 1 and 2, although the type which can use two types of gas as gas for atmosphere adjustment by providing two types of pressure regulators in parallel in the piping 1 was shown, it does not restrict to this. The fluorescent X-ray analyzer may be in a form in which three or more kinds of gases can be used as the atmosphere adjusting gas by providing three or more kinds of pressure regulators in parallel in the pipe 1.

DESCRIPTION OF SYMBOLS 1 Piping 11, 12, 13, 14 Branch pipe 21 Helium pressure regulator 22 Nitrogen pressure regulator 23 Large flow capillary 24 Small flow capillary 25 On-off valve 26 Switching valve (path switching means)
27 Flow control valve 31 Measurement chamber (internal space)
35 X-ray permeable membrane 37 Sealed space (internal space)
41 Sample cell 42 X-ray permeable membrane 51 X-ray tube (X-ray irradiation part)
52 X-ray detector (detector)
54 Control unit 55 Input unit

Claims (5)

The sample is irradiated with an X-ray irradiation unit that irradiates the sample with primary X-rays, a detection unit that detects fluorescent X-rays generated from the sample by irradiation with the primary X-rays, and the primary X-rays generated from the X-ray irradiation unit Fluorescence for performing fluorescent X-ray analysis after setting an internal space including at least a space through which the sample passes and a space through which the fluorescent X-rays generated from the sample enter the detection unit into an atmosphere of a specific gas In the X-ray analyzer,
Piping for supplying gas to the internal space;
A plurality of pressure regulators provided in parallel in the middle of the pipe;
Path switching means for selectively switching a path of gas supplied to the internal space from paths passing through the plurality of pressure regulators;
Each of the plurality of pressure regulators is configured to adjust the pressure of the gas supplied to the internal space to a pressure corresponding to each of the plurality of types of gases. . Each of the plurality of pressure regulators is configured such that the flow rate per unit time of gas supplied to the internal space through the pipe is a predetermined common flow rate that does not depend on the type of gas. The fluorescent X-ray analyzer according to claim 1, wherein The fluorescent X-ray analyzer according to claim 2, further comprising a flow rate adjusting unit that adjusts a flow rate per unit time of the gas supplied to the internal space to one of two predetermined flow rates. . The pipe is branched into two branch pipes having different flow rates per unit time of flowing gas,
The two branch pipes are both connected to the internal space,
The flow rate adjusting means is an on-off valve that closes and opens a branch pipe having a relatively large flow rate per unit time of gas among the two kinds of branch pipes. The described fluorescent X-ray analyzer. In the method of performing fluorescent X-ray analysis of a sample using the fluorescent X-ray analyzer according to claim 3 or 4,
The path switching means switches the gas path so that the gas passes through a pressure regulator corresponding to the type of gas supplied to the internal space,
Let the flow rate adjusting means adjust the flow rate per unit time of the gas supplied to the internal space to the larger flow rate of the two flow rates,
After the gas supply to the internal space is continued for a predetermined time, the flow rate per unit time of the gas supplied to the internal space is set to the smaller flow rate of the two stages. Let adjust
An X-ray fluorescence analysis method comprising: starting a fluorescent X-ray analysis after adjusting a flow rate of gas supplied to the internal space per unit time to a smaller one of the two stages of flow rates .

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