JP5524521B2 - X-ray fluorescence analyzer - Google Patents

Description

  The present invention relates to a fluorescent X-ray analyzer that analyzes a sample by detecting fluorescent X-rays generated by X-ray irradiation.

  Conventionally, as an apparatus for analyzing a sample, a fluorescent X-ray analyzer that irradiates the sample with primary X-rays and analyzes the composition has been used. The X-ray fluorescence analyzer detects fluorescent X-rays (secondary X-rays) generated when a sample is irradiated with primary X-rays with a detector, and is included in the sample from the spectrum distribution of the detected fluorescent X-rays. It is possible to specify an element and calculate the concentration of this element.

  When the sample is a fluid sample such as liquid or powder, the sample is accommodated in a container (hereinafter referred to as a sample cell) whose bottom is an X-ray transmitting film (X-ray transmitting window material), and the sample cell is fluorescent. Analysis with a fluorescent X-ray analyzer can be performed by irradiating primary X-rays from below the sample cell in a state of being placed on a measurement site of the X-ray analyzer. The primary X-rays irradiated from below the sample cell are irradiated to the flowing sample through the X-ray permeable film on the bottom surface of the sample cell, and the fluorescent X-rays generated at this time are detected by a detector disposed below the sample cell. It is detected through an X-ray permeable membrane.

  In Patent Document 1, as a sample cell table for holding a sample cell at a measurement site, a table frame is sandwiched between a table frame and a table frame mounted inside the table frame, and the table frame and the table frame. There has been proposed a fluorescent X-ray analyzer that uses a sample cell base made of an X-ray transmissive sheet that closes the inside of the frame, and the sample cell base is detachably provided at a measurement site. This X-ray fluorescence analyzer is used when the sample cell leaks when the sample cell is not fully assembled or when the X-ray transparent sheet of the sample cell is damaged due to an unexpected accident. Even if it exists, there will be no adverse effects such as adhesion of the leaked sample to the X-ray detector and the X-ray tube provided below the measurement site.

  FIG. 6 is a schematic diagram illustrating a configuration of a conventional X-ray fluorescence analyzer, which is substantially the same as the configuration of the X-ray fluorescence analyzer described in Patent Document 1. In the figure, reference numeral 101 denotes a fluorescent X-ray analyzer. The X-ray fluorescence analyzer 101 includes a cell holder (sample cell stage) 102 on which the sample cell 5 is placed, an X-ray tube 3 that irradiates the sample cell 5 with primary X-rays, and fluorescent X-rays generated by the primary X-ray irradiation. An X-ray detector for detection is provided.

  A sample cell 5 in which a fluid sample is accommodated has a cylindrical cell inner frame 51, a sample cup (inside that covers the inner surface, the outer surface, and the lower end portion of the cell inner frame 51 and has a recess for accommodating a fluid sample. Frame cover) 52 and a cylindrical cell outer frame 53 that fits outside the cell inner frame 51 covered by the sample cup 52, and the recess of the sample cup 52 in which the flowing sample is accommodated is an X-ray. It is sealed with a transmission window material (X-ray transmission sheet) 54. The X-ray transmission window material 54 is held in such a manner as to be sandwiched between the cell inner frame 51 covered with the sample cup 52 and the cell outer frame 53, and forms the bottom surface of the sample cell 5.

  The cell holder 102 on which the sample cell 5 is placed is an annular plate-shaped cell holder outer frame provided with a cell holder inner frame (base frame) 121 having an annular plate shape and a peripheral wall portion fitted on the cell holder inner frame 121. The cell holder inner frame 121 and the cell holder outer frame 122 are detachably attached to the measurement site of the fluorescent X-ray analyzer 101 in a state where the cell holder inner frame 121 and the cell holder outer frame 122 are overlapped with each other. Yes. An X-ray transmission window member 123 is held between the cell holder inner frame 121 and the cell holder outer frame 122, and circular openings formed at the centers of the cell holder inner frame 121 and the cell holder outer frame 122, respectively. It is covered and closed by an X-ray transmission window material 123.

  The cell holder inner frame 121 of the cell holder 102 is provided with an annular protrusion that protrudes upward over the entire circumference of the inner edge portion of the opening formed at the center. In the sample cell 5 in which the sample is accommodated, the lower end portion of the cell inner frame 51 of the sample cell 5 covered with the sample cup 52 and the X-ray transmission window material 54 is a protrusion provided on the cell holder inner frame 121 of the cell holder 102. Is placed on the cell holder 102 so as to abut on the cell holder 102. The primary X-ray from the X-ray tube 3 is irradiated to the flowing sample accommodated in the sample cell 5 through the X-ray transmissive window member 123 of the cell holder 102 and the X-ray transmissive window member 54 of the sample cell 5, and the fluorescence generated thereby. X-rays are similarly detected by the X-ray detector 4 through the X-ray transmission window members 54 and 123.

  For example, when the X-ray transmission window material 54 of the sample cell 5 is damaged, the flow sample accommodated in the sample cell 5 may flow out from the damaged portion of the X-ray transmission window material 54. Since the portion is closed by the X-ray transmission window member 123, there is no possibility that the fluid sample adheres to the X-ray tube 3 and the X-ray detector 4 inside.

Japanese Patent Laid-Open No. 9-127028

  However, when the sample cell 5 having the configuration shown in FIG. 6 is used, the X-ray transmission window material 54 may be bent due to a change in pressure in the sample cell 5 or the like. When the X-ray transmissive window member 54 is bent, or when a problem occurs in the assembly of the sample cell 5, the cell outer frame 53 comes into contact with the cell holder inner frame 121, and the lower surface of the sample cell 5 is tilted. Since the distance between the flow sample accommodated in the sample cell 5 and the X-ray detector 4 changes when placed on the cell holder 102, an error occurs in the analysis of the flow sample by X-ray, and the analysis accuracy There was a problem that decreased. This problem cannot be solved by the fluorescent X-ray analyzer described in Patent Document 1. Further, since the sample cell 5 is a general-purpose product, it is not preferable to solve the above problem by changing the shape of the sample cell 5 or the like.

  The present invention has been made in view of such circumstances, and an object of the present invention is to prevent occurrence of errors due to bending of an X-ray transmission window material (X-ray transmission film) provided in a sample cell. Another object of the present invention is to provide a fluorescent X-ray analyzer capable of performing highly accurate analysis on a flowing sample.

The fluorescent X-ray analysis apparatus according to the present invention includes a mounting unit on which a sample storage container whose opening is to be closed with an X-ray transmission window material is mounted, and the sample storage container mounted on the mounting unit In an X-ray fluorescence analyzer comprising: an X-ray irradiating means for irradiating primary X-rays; and a detecting means for detecting fluorescent X-rays from a sample stored in the sample container generated by the primary X-ray irradiation. The placement section includes a bottom plate portion having an opening through which primary X-rays pass from the X-ray irradiating means to the sample container, and an inner edge portion of the bottom plate portion projecting over the entire circumference of the opening portion. And supporting the sample storage container so that the primary X-ray passing through the opening reaches the X-ray transmission window material closing the opening of the sample storage container. and parts provided on the projecting end of the support portion, when the support portion for supporting the sample container And a supporting plane close to the X-ray transmission window material, the support plane is shaped to fit into the opening of the sample container at the inner side of the opening, the X-ray transmission of closing the opening Ri Citea as in contact with the window material for supporting the sample container, the opening of the mounting section can be closed by the X-ray transmission window material, the mounting section, the sample receiving When the container is placed, a through-hole communicating between the inside and the outside of the closed space constituted by the X-ray transmission window material of the sample storage container, the support portion, and the X-ray transmission window material to close the opening is provided. It is characterized by having .

  The X-ray fluorescence analyzer according to the present invention further includes an injection tube for injecting a gas into the closed space through the through hole.

  Further, in the fluorescent X-ray analysis apparatus according to the present invention, the mounting portion includes an annular inner frame provided with the support portion, and an annular outer frame that is externally fitted to the inner frame. The X-ray transmission window material can be sandwiched between the inner frame and the outer frame.

  Further, in the X-ray fluorescence analyzer according to the present invention, the placement unit is detachably provided in a housing holding the X-ray irradiation unit and the detection unit, and the placement unit is attached to the housing. It is further characterized by further comprising a fixing portion for pressing and fixing.

In the present invention, the fluorescent X-ray analyzer is provided with a mounting portion for mounting a sample storage container (sample cell) for storing a sample, and is passed through an X-ray transmission window material (X-ray transmission film) provided in the sample cell. The sample is analyzed by irradiating the sample with primary X-rays and detecting fluorescent X-rays from the sample. As the sample cell, a general-purpose cell in which the opening of the container is closed with an X-ray transmission window material can be used.
The mounting portion for mounting the sample cell has an opening for passing primary X-rays irradiated from the X-ray irradiation means to the sample cell (sample contained therein) and fluorescent X-rays from the sample cell to the detection means. It is formed. Further, the mounting part has a support part for supporting the sample cell, and the support part is arranged such that, for example, the X-ray transmission window material of the sample cell is positioned above the opening part. The sample cell is supported so as to reach the transmission window material. Further, the support portion for supporting the sample cell is in contact with the X-ray transmission window material provided in the inner portion of the opening of the sample cell (that is, the portion where the sample exists on the opposite side of the X-ray transmission window material). The sample cell).
In the conventional X-ray fluorescence spectrometer 101 shown in FIG. 6, the cell holder 102 supports the sample cell 5 by contacting the lower end portion of the cell inner frame 51 of the sample cell 5. The cell holder with the lower surface (bottom surface) of the sample cell 5 tilted due to factors such as the position of the X-ray transmissive window material 54 being changed due to bending or the cell outer frame 53 coming into contact with the cell holder inner frame 121. There is a possibility that the position of the sample in the sample cell 5 with respect to the X-ray detector 4 may change due to being placed on 102. On the other hand, in the configuration in which the support portion of the mounting portion abuts against the X-ray transmission window material inside the opening and supports the sample cell as in the present invention, the support position of the X-ray transmission window material by the support portion is changed. The accuracy can be greatly improved.
Therefore, even if the X-ray transmissive window material of the sample cell is bent or a problem occurs in the assembly of the sample cell, the position of the X-ray transmissive window material relative to the X-ray detection means is prevented from changing. In addition, since it is possible to suppress a change in the position of the sample in the sample cell with respect to the X-ray detection means, it is possible to suppress a decrease in the analysis accuracy of the sample.

  In the present invention, the portion where the support portion of the placement portion abuts against the X-ray transmission window material of the sample cell is a flat surface, and the placement portion is placed in close contact with the X-ray transmission window material of the sample cell in this plane. The prepared sample cell is supported. By supporting the sample cell in close contact with the flat surface, the sample cell can be stably supported, and bending of the X-ray transmission window material of the sample cell can be suppressed.

In the X-ray fluorescence analyzer, air is excluded from the primary X-ray path from the X-ray irradiating means to the sample and the fluorescent X-ray path from the sample to the fluorescent X-ray detecting means, and a gas such as helium is used. By satisfying this, it is possible to eliminate error factors such as argon in the air and improve the analysis accuracy of the sample by X-rays. For this reason, it is conceivable that the X-ray irradiation means and the detection means are arranged in a sealed casing, and the sealed space in the casing is filled with helium gas to perform primary X-ray irradiation and fluorescent X-ray detection.
On the other hand, the opening of the mounting portion can be closed with an X-ray transmission window material, whereby the X-ray transmission window material serves as a protective film, and the protective film of the sample cell is damaged. In the case of spilling or the like, it is possible to prevent the sample from adhering to the X-ray irradiation means, the detection means and the like through the opening of the mounting portion.
However, in the case where the opening portion of the mounting portion is closed by the X-ray transmission window material, the sealed space in which the X-ray irradiation means and the detection means are provided and the sample cell are placed between the X-ray transmission window material. The placed space is isolated. Therefore, even if the sealed space provided with the X-ray irradiation means and the detection means is filled with helium gas, the air is present in the space from the X-ray transmission window material to the sample cell, so that the analysis accuracy is reduced. There's a problem.
Therefore, in the present invention, when the opening portion of the placement portion is closed by the X-ray transmission window material, the support portion is erected over the entire circumference of the opening portion of the placement portion, and the sample cell placed A closed space is formed that is surrounded by the X-ray transmission window material and the X-ray transmission window material that closes the opening of the mounting portion and the support portion of the mounting portion. Further, the mounting portion is provided with a through hole that communicates the inside and outside of the closed space. As a result, helium gas or the like can be injected into the closed space through the through hole of the mounting portion, and the space from the X-ray transmission window material of the mounting portion to the sample cell is filled with helium gas and the like. Analysis accuracy can be improved.
Furthermore, a through hole for discharging a gas such as air in a closed room may be provided separately from the through hole for injecting helium gas or the like.

  In the present invention, the fluorescent X-ray analyzer includes an injection tube for injecting a gas such as helium gas into the closed space through the through hole of the mounting portion. Thereby, gas can be efficiently inject | poured and filled in the closed place comprised by the sample cell and the mounting part.

  In the present invention, the mounting portion for mounting the sample cell is configured to fit an annular inner frame provided with a support portion that supports the sample cell and an annular outer frame provided with an opening. The X-ray transmission window material is held between the inner frame and the outer frame. Thereby, since the X-ray transmissive window material can be firmly held, the X-ray irradiation means, the detection means, and the like can be reliably protected from the sample flowing out from the sample cell. Further, the X-ray transmission window material can be easily replaced by releasing the fitting of the inner frame and the outer frame.

Further, in the present invention, a mounting portion for mounting the sample cell is detachably provided on the housing of the fluorescent X-ray analyzer holding the X-ray irradiation means, the detection means, and the like. This makes it possible to more easily replace the X-ray transmissive window material that closes the opening of the mounting portion.
However, if a change occurs in the mounting position of the mounting portion in this configuration, the position of the mounted sample cell and the detection means may change, which may reduce the analysis accuracy. Therefore, in the present invention, the fluorescent X-ray analyzer is provided with a fixing portion that presses and fixes the mounting portion against the housing, thereby preventing a change in the position of the placement portion and preventing a decrease in analysis accuracy. .

  In the case of the present invention, a support part for supporting the sample cell is provided on the mounting part for mounting the sample cell, and supported by the X-ray transmission window material (X-ray transmission film) provided in the inner part of the opening of the sample cell. Even if there is a problem in the assembly of the sample cell or the X-ray transmission window material of the sample cell is bent, the portion of the X-ray transmission of the fluorescent X-ray is supported. Since the position of the detection means and the X-ray transmission window material of the sample cell does not change, that is, the position of the detection means and the sample does not change, the analysis accuracy of the sample by X-rays does not decrease, and the fluorescent X-ray analysis apparatus High-precision analysis can be realized.

  Further, according to the present invention, the opening of the mounting part is closed with an X-ray transmission window material, a support part is provided over the entire circumference of the opening of the mounting part, and the X-ray transmission window material of the sample cell, By providing a closed space surrounded by an X-ray transmission window material that closes the support and the opening, and by providing a through hole that communicates the inside and outside of this closed space, helium gas and the like are injected into the closed space through the through hole. And since the space from the X-ray transparent film of a mounting part to a sample cell can be filled with helium gas etc., the analysis precision by a fluorescent X-ray analyzer can be improved more.

It is a schematic diagram which shows schematic structure of a fluorescent X ray analyzer. It is a schematic diagram which shows the structure of the fluorescent X-ray analyzer which concerns on this invention. It is a disassembled perspective view which shows the structure of a sample cell. It is a disassembled perspective view which shows the structure of a cell holder. It is a schematic diagram for demonstrating the injection | pouring method of gas, such as helium gas. It is a schematic diagram which shows the structure of the conventional fluorescent X ray analyzer.

  Hereinafter, the present invention will be specifically described with reference to the drawings showing embodiments thereof. FIG. 1 is a schematic diagram showing a schematic configuration of a fluorescent X-ray analyzer. In the figure, reference numeral 1 denotes a housing of the fluorescent X-ray analyzer. The upper portion of the housing 1 is a flat surface, and an operator who uses the fluorescent X-ray analyzer can use it as a work table. An opening is formed at the center of the upper plane of the housing 1, and a cell holder (mounting portion) 2 is mounted in a form fitted inside the opening, and a sample cell (sample storage container) in which a sample to be analyzed is stored. ) 5 is placed on the cell holder 2. When analyzing the sample by X-ray, the sample cell 5 placed on the cell holder 2 is covered with the cover 7.

  An X-ray detector (detection means) 4 is fixed to the housing 1 immediately below the opening in which the cell holder 2 is mounted, and an X-ray tube (X-ray irradiation means) 3 is fixed at a position 30 ° obliquely below the opening. Has been. The X-ray tube 3 guides X-rays generated by the X-ray source to a predetermined irradiation range, and is directed to the bottom of the sample cell 5 placed on the cell holder 2 (that is, the sample accommodated in the sample cell 5). F) Irradiate primary X-rays. The X-ray detector 4 detects fluorescent X-rays generated when the X-ray tube 3 irradiates the sample in the sample cell 5 with primary X-rays, and the detection result is not shown in a PC (Personal Computer) or the like. Output to the processing device. Although details will be described later, the cell holder 2 is provided with an X-ray transmission window material (X-ray transmission film) 23, and an X-ray transmission window material (X-ray transmission film) 54 is provided at the bottom of the sample cell 5. The primary X-ray from the X-ray tube 3 is irradiated to the sample in the sample cell 5 through the X-ray transmission window members 23 and 54, and the fluorescent X-ray from the sample passes through the X-ray transmission window members 54 and 23. It reaches the detector 4 and is detected (see the broken arrow in the figure).

  Further, the opening of the housing 1 is closed by the mounting of the cell holder 2, and the inside of the housing 1 becomes a sealed space (analysis chamber 1a). When analyzing the sample, helium gas is injected into the housing 1 from the injection port 11 (see the solid line arrow in the figure), and the analysis chamber 1a is filled with helium gas. Further, the space between the X-ray transmissive window member 23 of the cell holder 2 and the X-ray transmissive window member 54 of the sample cell 5 is also helium from the injection tube 15 (see FIG. 5) when analyzing the sample. Gas is injected.

  FIG. 2 is a schematic diagram showing a configuration of a fluorescent X-ray analyzer according to the present invention. FIG. 3 is an exploded perspective view showing the configuration of the sample cell 5, and FIG. 4 is an exploded perspective view showing the configuration of the cell holder 2. The sample cell 5 includes a cell inner frame 51, a sample cup 52, a cell outer frame 53, and an X-ray transmission window material 54. The cell inner frame 51 has a cylindrical shape and is formed of plastic such as polyethylene or metal. At the upper end portion of the cell inner frame 51, a flange portion 51a is provided over the entire circumference of the outer peripheral surface. Further, a groove 51b is formed on the outer peripheral surface of the cell inner frame 51 at a central position in the axial direction over the entire circumference, and an annular protrusion 51c is formed on the inner peripheral surface of the cell inner frame 51 over the entire circumference. Is protruding.

  The sample cup 52 is formed by bending a soft plastic film, and is connected to a cylindrical sample storage portion 52a having a top surface and having an opening 52d at the bottom, and a lower end of the sample storage portion 52a. A cylindrical enclosure 52b provided to surround the outer peripheral surface of the sample storage portion 52a with a predetermined interval, and a flange 52c provided over the entire outer peripheral surface at the upper end of the enclosure 52b. And have. The outer diameter of the sample storage portion 52 a is smaller than the inner diameter of the cell inner frame 51, and the inner diameter of the surrounding portion 52 b is substantially equal to the outer diameter of the cell inner frame 51. Therefore, the cell inner frame 51 is inserted from above into the space between the sample storage portion 52a and the surrounding portion 52b of the sample cup 52 until the flange portion 51a of the cell inner frame 51 and the flange portion 52c of the sample cup 52 come into contact with each other. can do. When the cell inner frame 51 is inserted into the sample cup 52, the cell inner frame 51 is fitted into the surrounding portion 52 b of the sample cup 52, and the inner peripheral surface of the cell inner frame 51 and the outer peripheral surface of the sample storage portion 52 a of the sample cup 52. A gap is provided between the two.

  The X-ray transmission window material 54 has a substantially circular thin sheet shape having a diameter sufficiently larger than the outer diameter of the sample cup 52, and does not pass a fluid sample such as liquid or powder, but transmits X-rays. It is made of material. The X-ray transmission window material 54 forms the bottom surface of the sample cup 52 (that is, the sample cell 5) by covering the opening 52d at the bottom of the sample cup 52 in which the sample is accommodated.

  The cell outer frame 53 has a cylindrical shape and is formed of plastic such as polyethylene or metal, and the cell inner frame 51 inserted into the sample cup 52 is inserted into the cell outer frame 53 to be fitted. Can do. At this time, the opening 52 d at the bottom of the sample cup 52 is covered with the X-ray transmission window member 54 and inserted into the cell outer frame 53, so that the outer edge side portion of the X-ray transmission window member 54 becomes the sample cup 52. The X-ray transmissive window material 54 is firmly used as the bottom surface of the sample cell 5 so that the sample in the sample cup 52 is not spilled from the opening 52d. Fixed to.

  At the upper end portion of the cell outer frame 53, a flange portion 53a is provided over the entire circumference of the outer peripheral surface, and the flange portion 53a connects the fitted cell inner frame 51 and sample cup 52 to the respective flange portions 51a and 51a. It is supported at 52c. Further, on the inner peripheral surface of the cell outer frame 53, a protrusion 53b is provided over the circumference at a position corresponding to the groove 51b provided on the outer peripheral surface of the cell inner frame 51. The groove 51b of the cell inner frame 51 fitted in the cell outer frame 53 is engaged with the enclosing portion 52b of the sample cup 52 and the X-ray transmission window material 54 sandwiched therebetween. As a result, the sample cup 52 and the X-ray transmission window material 54 are firmly sandwiched between the cell inner frame 51 and the cell outer frame 53.

  2 and 3 and the above description, the vertical direction of the sample cell 5 is determined based on the arrangement when the sample is analyzed by the fluorescent X-ray analyzer. When the sample is stored, the sample cell 5 is used upside down. That is, the sample cup 52 is placed on the cell inner frame 51 with the flange 51a on the lower side, the sample is poured into the sample storage portion 52a of the sample cup 52 from the opening 52d, and the opening 52d of the sample cup 52 is transmitted through X-rays. The sample cell 5 is assembled and the sample is accommodated by covering with the window material 54 and fitting the cell outer frame 53 from the upper side. Thereafter, the sample cell 5 is placed on the cell holder 2 with the X-ray transmissive window material 54 covering the opening 52d of the sample cup 52 being the bottom surface by turning the sample cell 5 upside down.

  The cell holder 2 includes a cell holder inner frame 21, a cell holder outer frame 22, and an X-ray transmission window member 23. The cell holder inner frame 21 is made of metal such as copper or aluminum, and has a disc-shaped (that is, annular) bottom plate portion 21a having an opening 21c formed at the center. The cell holder inner frame 21 is preferably made of copper or the like in order to prevent an influence on measurement accuracy due to irradiation with primary X-rays. A cylindrical peripheral wall portion 21b is erected substantially vertically upward at the outer edge portion of the bottom plate portion 21a. The inner diameter of the peripheral wall portion 21b is larger than the outer diameter of the cylindrical portion of the cell outer frame 53 of the sample cell 5, The height of the peripheral wall portion 21b is sufficiently lower than the height of the sample cell 5 in the axial direction.

Further, the cell holder inner frame 21 is provided on the inner edge portion (peripheral portion of the opening portion 21c) of the bottom plate portion 21a so as to project obliquely upward toward the inside of the opening portion 21c over the entire circumference of the opening portion 21c. have. That is, the support portion 24 has a cylindrical shape (substantially frustoconical shape) whose diameter is reduced upward, and an annular horizontal and smooth support plane 24 a is formed at the protruding end portion (upper end portion) of the support portion 24. . The outer diameter of the support plane 24 a is smaller than the diameter of the opening 52 d provided at the bottom of the sample cup 52 of the sample cell 5. The support part 24 is arranged so that the X-ray transmission window material 54 of the sample cell 5 faces the opening 21c of the mounting part 2, and primary X-rays from the X-ray tube 3 pass through the opening 21c and the X-rays of the sample cell 5 The height, the size of the support plane 24a, and the like are appropriately set so as to reach the transmission window material 54.
The illustrated support portion 24 has a cylindrical shape whose diameter is reduced to the upper side. However, the present invention is not limited to this, and the support portion 24 is provided substantially perpendicularly to the periphery of the opening 52d, and the upper end portion is directed toward the shaft core. It is good also as a structure which provides the annular | circular shaped support plane 24a. In this case, the outer diameters of the support portion 24 and the support plane 24 a are formed to be smaller than the diameter of the opening 52 d of the sample cell 5.

  The X-ray transmissive window member 23 has a substantially circular thin sheet shape having a diameter larger than the outer diameter of the cell holder inner frame 21, and is similar to the X-ray transmissive window member 54 of the sample cell 52. However, it is made of a substance that transmits X-rays. The X-ray transmission window member 23 covers and closes the opening 21c of the cell holder inner frame 21, whereby the analysis chamber 1a of the X-ray fluorescence analyzer is sealed.

  The cell holder outer frame 22 has an annular bottom plate portion 22a. The inner diameter of the bottom plate portion 22 a is larger than the inner diameter of the bottom plate portion 21 a of the cell holder inner frame 21. A cylindrical peripheral wall portion 22b that is externally fitted to the cell holder inner frame 21 is erected substantially vertically upward at an outer edge portion of the bottom plate portion 22a. The cell holder inner frame 21 and the cell holder outer frame 22 are fitted with the X-ray transmission window member 23 interposed therebetween, whereby the X-ray transmission window member 23 is firmly held with the opening 21c closed. In a state where the cell holder inner frame 21 and the cell holder outer frame 22 are fitted, the peripheral wall portion 21 b of the cell holder inner frame 21 protrudes slightly above the peripheral wall portion 22 b of the cell holder outer frame 22.

  The cell holder 2 assembled by fitting the cell holder inner frame 21 and the cell holder outer frame 22 with the X-ray transmission window member 23 interposed therebetween closes the opening formed on the upper surface of the casing 1 of the fluorescent X-ray analyzer. In this way, it is detachably mounted. The mounted cell holder 2 is pressed and firmly fixed to the housing 1 by a holder press (fixing part) 13, and then the sample cell 5 in which the sample is accommodated is placed on the cell holder 2.

The holder presser 13 has an annular shape and is formed of metal or plastic. The inner diameter of the holder presser 13 is substantially equal to the inner diameter of the peripheral wall portion 21 provided on the cell holder inner frame 21 of the cell holder 2, and abuts against the upper end surface of the peripheral wall portion 21 that forms the upper end of the cell holder 2 attached to the housing 1. Then, the cell holder 2 is pressed downward. The holder holder 13 is fixed to the housing 1 with screws 14 while the cell holder 2 is pressed. In addition, an injection tube 15 described later can be configured to be fixed to the holder presser 13.
The configuration of the holder presser 13 is not limited to the configuration in which the holder presser 13 is removably screwed to the housing 1 as shown in the figure. For example, a hinge mechanism or the like is provided on one side of the holder presser 13 so that the holder presser 13 can swing. It is good also as a structure which attaches the holder holding | maintenance 13 so that it may become, and fixes the other side with the screw | thread 14. Further, the fixing of the holder presser 13 to the housing 1 is not limited to the screw 14, and may be fixed using, for example, a fastening fitting such as a snap lock. It is desirable that the holder presser 13 has a configuration that can be easily detached from the housing 1.

  Although the sample cell 5 is placed on the support portion 24 of the cell holder 2, in the fluorescent X-ray analysis apparatus according to the present invention, the outer diameter of the support plane 24 a of the support portion 24 is the opening 52 d at the bottom of the sample cell 5. Smaller than diameter. For this reason, the support plane 24a can contact the X-ray transmission window member 54 provided so as to cover the opening 52 on the inner side of the edge portion of the opening 52d of the sample cell 5 to support the sample cell 5. . The support portion 24 of the cell holder 2 is erected with a sufficient height so that the lower end of the cell outer frame 53 of the sample cell 5 does not contact the upper surface of the bottom plate portion 21 a of the cell holder inner frame 21. Therefore, the contact portion between the cell holder 2 and the sample cell 5 is only the support plane 24a of the support portion 24 and the lower surface of the X-ray transmission window member 54 that closes the opening 52d, and the cell holder 2 and the sample cell at other locations. 5 does not contact. Furthermore, the contact portion of the X-ray transmission window material 54 of the sample cell 5 that contacts the support plane 24a of the cell holder 2 is only the portion where the sample exists on the upper surface, and the lower end of the sample cup 52 exists on the upper surface. The X-ray transmissive window material 54 does not come into contact with the support flat surface 24a in the portion where it does.

  Thereby, even if there is a problem in the assembly of the sample cell 5 or the X-ray transmission window material 54 is bent, the X-ray transmission of the sample cell 5 with respect to the position of the support portion 24 of the cell holder 2 is achieved. The position of the window material 54 does not fluctuate (however, the positions of other portions such as the cell inner frame 51 and the cell outer frame 53 of the sample cell 5 fluctuate with respect to the position of the support portion 24). Therefore, even if there is a problem in the assembly of the sample cell 5 or the X-ray transmission window material 54 is bent, the position of the X-ray transmission window material 54 (that is, the sample accommodated in the sample cell 5). ) And the position of the X-ray detector 4 do not fluctuate, and the X-ray detector 4 can detect the fluorescent X-rays with high accuracy.

  Further, by placing the sample cell 5 on the cell holder 2, the support plane 24 a of the support portion 24 of the cell holder 2 is brought into close contact with the X-ray transmission window material 54 at the bottom of the sample cell 5, thereby the X-ray of the sample cell 5. A substantially frustoconical substantially sealed space (closed) surrounded by the transmission window member 54, the support portion 24 of the cell holder 2 and the X-ray transmission window member 23 is formed. In the X-ray fluorescence analyzer according to the present invention, the substantially closed space is filled with a gas such as helium gas in the same manner as the analysis chamber 1a, and X-ray irradiation and detection are performed to improve the analysis accuracy. . Therefore, an injection hole (through hole) 25 for injecting a gas such as helium gas into the substantially sealed space is formed in the cell holder inner frame 21 of the cell holder 2.

  FIG. 5 is a schematic view for explaining a method of injecting a gas such as helium gas, and is a side sectional view in which the support portion 24 of the cell holder 2 and the vicinity thereof are enlarged. 5A shows a side cross section of the support portion 24 at a position where the injection hole 25 is not formed, and FIG. 5B shows a side cross section of the support portion 24 at a position where the injection hole 25 is formed. It is shown.

  The injection hole 25 is an oblong through-hole that is long in the radial direction of the cell holder inner frame 21 when viewed from the top of the cell holder inner frame 21, penetrates the upper and lower sides of the cell holder inner frame 21, and covers the inclined portion of the support portion 24. It is formed so as to penetrate from the side to the other side. That is, one end portion of the injection hole 25 reaches the inner wall portion of the peripheral wall portion 21 b, and the other end portion of the injection hole 25 reaches the outer edge portion of the support plane 24 a of the support portion 24. Thereby, the substantially sealed space surrounded by the X-ray transmission window material 54 of the sample cell 5, the support portion 24 of the cell holder 2 and the X-ray transmission window material 23 communicates with the inside and outside only through the injection hole 25. A gas such as helium gas can be injected into the substantially sealed space through.

  The X-ray fluorescence analyzer includes an injection tube 15 for injecting a gas such as helium gas into the substantially sealed space through the injection hole 25. The injection tube 15 is a straight thin tube formed of metal, plastic, or the like, and the distal end portion of the injection tube 15 is bent into a substantially L shape. The straight end portion (first portion 15a) at the extreme end of the injection tube 15 is slightly shorter than the length of the injection hole 25 in a top view, and the first portion 15a of the injection tube 15 enters the injection hole 25 from the upper side of the cell holder 2. Is inserted substantially horizontally, and the air outlet at the tip of the first portion 15a is installed so as to face the inside of the sealed space. Further, the second portion 15b that is substantially perpendicular to the first portion 15a of the injection tube 15 is substantially perpendicular to the peripheral wall portion 21b of the cell holder inner frame 21 when the first portion 15a is inserted into the injection hole 25. Arranged.

  Although not shown, the opposite end of the injection tube 15 is connected to a gas supply source such as a gas cylinder through an electromagnetic valve or the like, and is supplied from the gas supply reduction before starting the analysis by X-ray. A gas such as helium gas is injected into the substantially sealed space from the injection tube 15. Alternatively, the opposite end of the injection tube 15 may be connected to the analysis chamber 1 a in the housing 1, and in this case, a gas such as helium gas in the analysis chamber 1 a is substantially sealed through the injection tube 15. Injected into.

  The injection tube 15 is inserted into the injection hole 25 of the cell holder 2 after the cell holder 2 is mounted on the housing 1 and before the sample cell 5 is placed on the cell holder 2. The injection tube 15 is attached to a holder holder 13 that presses the cell holder 2 against the housing 1. Inserted into. Although illustration is omitted, the injection tube 15 may be configured such that the tip portion thereof is inserted from the outside to the inside (from the upper side to the lower side) through the opening of the holder holder 13. The structure which forms the notch to pass or a through-hole etc. may be sufficient.

  An operator who analyzes a sample using the fluorescent X-ray analyzer 1 assembles the cell holder 2, attaches it to the housing 1, fixes it with the holder holder 13, and inserts the injection tube 15 into the injection hole 25 of the cell holder 2. After inserting and placing the sample cell 5 containing the sample on the cell holder 2 and covering the sample cell 5, the cell holder 2 and the like with the cover 7, the analysis of the sample can be started. The fluorescent X-ray analyzer firstly injects a gas such as helium gas into the analysis chamber 1a in the housing 1 from the injection port 11, and at the same time, the X-ray transmission window material 54 of the sample cell 5, the support 24 of the cell holder 2, and A gas such as helium gas is injected from the injection tube 15 through the injection hole 25 into a substantially sealed space surrounded by the X-ray transmission window member 23. After the gas is sufficiently filled, the X-ray fluorescence analyzer irradiates primary X-rays from the X-ray tube 3 to the bottom of the sample cell 5, whereby X-rays emitted from the sample in the sample cell 5 are emitted as X-rays. The sample can be analyzed by detecting with the line detector 4 and examining the spectrum distribution of the detected fluorescent X-rays.

  In the fluorescent X-ray analysis apparatus having the above configuration, the support portion 24 protrudes from the periphery of the opening 21 c provided in the cell holder inner frame 21 of the cell holder 2, and the support plane 24 a provided at the protruding end portion of the support portion 24 is provided. The configuration in which the sample cell 5 is supported by contacting the X-ray transmissive window material 54 provided inside the opening 52d at the bottom of the sample cell 5 may cause problems in assembly of the sample cell 5 or may cause X-ray transmission. Even if the window material 54 is bent, the position of the X-ray transmission window material 54 relative to the X-ray detector 4 does not change, and the position of the sample in the sample cell 5 does not change. A reduction in analysis accuracy of the X-ray analyzer can be prevented. In addition, since the contact between the sample cell 5 and the support portion 24 is performed by the annular support plane 24a, the contact between the sample cell 5 and the support portion 24 can be performed in a wide area, and the support plane. 24a can be brought into close contact with the X-ray transmission window material 54 of the sample cell 5, and the sample cell 5 can be stably supported.

  Further, by configuring the opening 21c of the cell holder 2 with the X-ray transmission window member 23, even if the X-ray transmission window member 54 of the sample cell 5 is damaged and the sample spills out, Since the sample can be prevented from flowing into the analysis chamber 1a of the housing 1 using the X-ray transmission window member 23 as a protective film, there is no possibility of the sample adhering to the X-ray tube 3 and the X-ray detector 4 or the like. Further, the X-ray transmission window member 23 is sandwiched and held between the cell holder inner frame 21 and the cell holder outer frame 22 of the cell holder 2, whereby the X-ray transmission window member 23 can be firmly held, and the analysis chamber The inside of 1a can be reliably protected. In addition, by adopting a configuration in which the cell holder 2 is detachably attached to the housing 1, the X-ray transmissive window member 23 can be easily replaced. In addition, by adopting a configuration in which the cell holder 2 attached to the housing 1 is pressed and fixed to the housing 1 by the holder retainer 13, the position variation of the cell holder 2 can be prevented and the analysis accuracy can be prevented from being lowered. be able to.

  Further, the injection inserted into the injection hole 25 in the substantially sealed space surrounded by the X-ray transmission window material 54 of the sample cell 5 placed on the cell holder 2, the support portion 24 of the cell holder 2 and the X-ray transmission window material 23. By injecting a gas such as helium gas from the tube 15 and also injecting a gas such as helium gas into the analysis chamber 1 a in the housing 1, the X-ray tube 3 to the sample cell 5 and the sample cell 5 are configured. To the X-ray detector 4 can be filled with a gas such as helium gas, and an error factor such as argon in the air can be eliminated and the analysis accuracy of the sample by X-ray can be improved.

  In the present embodiment, the X-ray detector 4 is disposed immediately below the cell holder 2 and the sample cell 5 and the X-ray tube 3 is disposed at a position 30 ° obliquely below. Instead, for example, the X-ray tube 3 may be disposed immediately below the cell holder 2 and the sample cell 5, and the X-ray detector 4 may be disposed at an obliquely lower 30 ° position, or other configurations may be employed. In addition, a gas such as helium gas is injected into the analysis chamber 1a of the housing 1 and the substantially sealed space surrounded by the X-ray transmission window member 54, the support 24, and the X-ray transmission window member 23. However, the present invention is not limited to this, and an X-ray analysis may be performed without injecting a gas such as helium gas. In this case, since it is not necessary to form a substantially sealed space by the X-ray transmissive window material 54, the support portion 24, and the X-ray transmissive window material 23, for example, the support portion 24 is not provided over the entire circumference of the opening 21c. It is good also as a structure which provides the several support part 24 in the periphery of the opening part 21c at a fixed space | interval.

  Further, the shape of the sample cell 5 shown in FIG. 3 and the like is merely an example, and the shape is not limited to this, and any container may be used as long as the X-ray transmission window material 54 is provided on the bottom surface. In addition, the shape of the injection tube 15 (the shape in which the distal end portion is bent in a substantially L shape) shown in FIG. 5 and the like is merely an example, and other shapes may be used. For example, the injection tube 15 does not have the first portion 15a arranged in the horizontal direction in the injection hole 25, and injects a gas such as helium gas into the substantially sealed space from the air outlet provided on the side surface of the second portion 15b. It is good also as composition to do. Furthermore, although the example which provides the cell holder 2 with respect to the housing | casing 1 was described, it does not restrict to this, The X-ray transmissive window material 23 may be fixed with respect to the housing | casing 1. FIG. In this case, the support part 24 may be provided separately from the X-ray transmissive window member 23. In addition, the sample cell 5, the X-ray transmission window member 54 that closes the opening 52d of the sample cell 5, and the X-ray transmission window member 23 that closes the opening 21c of the cell holder 2 are interchangeable general-purpose consumables. These consumables may not be included in the sales mode of the fluorescent X-ray analyzer.

DESCRIPTION OF SYMBOLS 1 Case 1a Analysis room 2 Cell holder (mounting part)
3 X-ray tube (X-ray irradiation means)
4 X-ray detector (detection means)
5 Sample cell (sample container)
7 Cover 13 Holder holder (fixed part)
15 Injection pipe 21 Cell holder inner frame (inner frame)
21c Opening 22 Cell holder outer frame (outer frame)
23 X-ray transmission window material 24 Support part 24a Support plane 25 Injection hole (through hole)
51 Cell inner frame 52 Sample cup 52d Opening 53 Cell outer frame 54 X-ray transmission window material

Claims (4)

A mounting portion on which a sample storage container whose opening is to be blocked by an X-ray transmission window material is mounted, and an X-ray irradiation means for irradiating the sample storage container mounted on the mounting portion with primary X-rays And a fluorescent X-ray analyzer comprising: detection means for detecting fluorescent X-rays from the sample stored in the sample storage container generated by irradiation with primary X-rays;
The placement section is
A bottom plate portion formed with an opening through which primary X-rays pass from the X-ray irradiation means to the sample container;
A cylindrical shape is provided on the inner edge of the bottom plate over the entire circumference of the opening to reduce the diameter toward the protruding end, and the primary X-ray passing through the opening closes the opening of the sample container. A support portion for supporting the sample container so as to reach the X-ray transmission window material ;
A support plane that is provided at the projecting end of the support portion and is in close contact with the X-ray transmission window material when the support portion supports the sample container ;
The support surface is shaped to fit into the opening of the sample container at the inner side of the opening, so as to support the sample container in contact with the X-ray transmission window material of closing the opening Oh it is,
The opening of the mounting portion can be closed with an X-ray transmission window material,
The placement section is configured by an X-ray transmission window material that should close the X-ray transmission window material, the support section, and the opening of the sample storage container when the sample storage container is placed. A fluorescent X-ray analyzer having a through-hole communicating between the inside and the outside of a closed place . The fluorescent X-ray analyzer according to claim 1 , further comprising an injection tube for injecting gas into the closed space through the through hole. The placement section is
An annular inner frame provided with the support,
An annular outer frame that is externally fitted to the inner frame,
The X-ray fluorescence analyzer according to claim 1 or 2 , wherein the X-ray transmission window material can be sandwiched between the fitted inner frame and outer frame. The placement unit is detachably provided on a housing holding the X-ray irradiation unit and the detection unit,
The fluorescent X-ray analysis apparatus according to any one of claims 1 to 3 , further comprising a fixing portion that presses and fixes the mounting portion against the housing.

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