JPH05256802A - Instrument for x-ray fluorescence analysis - Google Patents

Abstract

PURPOSE:To surely avoid the occurrence of such a trouble that the assay of a sample is started in an atmosphere which is not suitable to the kind of the sample. CONSTITUTION:The analyzing instrument is provided with a means 44 which detects the kind of a sample and means 18 which detects the atmosphere in an analysis chamber in which the sample is set so that it can be discriminated that whether or not the atmosphere is suitable to the kind of the sample based on the detecting outputs of both means 44 and 18. In addition, the instrument is also provided with an alarming means 46 which recognizes the occurrence of abnormality and issues an alarm in case the atmosphere is not suitable to the kind of the sample.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an X-ray fluorescence analyzer.

[0002]

2. Description of the Related Art Generally, in an X-ray fluorescence analyzer,
In some cases, it is necessary to analyze not only solid samples such as metals but also liquid samples such as oil and plating solutions.

Conventionally, in the case of analyzing a solid sample, the inside of an analysis chamber in which the sample is housed is kept in a vacuum state in order to avoid the influence of absorption attenuation of fluorescent X-rays due to oxygen in the atmosphere. On the other hand, when analyzing a liquid sample, a dedicated sample container for sealing the liquid is used. And
An X-ray transmission window made of a polymer thin film made of polyester or the like having relatively low X-ray absorption is provided on the upper portion of the sample container.

By the way, in the case of analyzing a liquid sample, when the inside of the analysis chamber is evacuated as in the case of analyzing a solid sample, the X-ray transmission window is opened due to the pressure difference between the inside of the sample container and the analysis chamber. It breaks easily, resulting in the inconvenience of splashing and contaminating the liquid sample into the analysis chamber.

In order to improve this, it is possible to use, for example, a Be film having a relatively high strength instead of the above-mentioned polymer thin film as a material for the X-ray transmission window. In the case of a film, particularly in the case of analyzing light elements of Al or more, the absorption of fluorescent X-rays is large, the detection intensity is lowered, and accurate analysis results cannot be obtained. Therefore, when analyzing a liquid sample, conventionally, the inside of the analysis chamber is kept at atmospheric pressure to prevent the X-ray transmission window from being damaged, and the atmosphere is replaced with He gas to minimize the absorption of fluorescent X-rays. I am trying to. In the case of analyzing heavy elements, since the absorption attenuation of fluorescent X-rays is also relatively small, it may be analyzed in an air atmosphere without He gas replacement.

[0006]

As described above, it is necessary to create an appropriate atmosphere in the analysis chamber depending on the type of sample. Conventionally, however, the selection of this atmosphere must be decided by the analyst on a case-by-case basis. I am going. Therefore, due to the error of the analyst, even if it is a solid sample, analysis may be performed at atmospheric pressure, or a vacuum may be drawn even if it is a liquid sample. However, there have been problems such as not being obtained, and the liquid sample being scattered to contaminate the inside of the analysis chamber.

The present invention has been made in order to solve such a problem, and it is sure that the inconvenience that an analysis is performed in an atmosphere that is not compatible with the type of sample is caused by the error of the analyst. The task is to be able to avoid it.

[0008]

The present invention adopts the following constitution in order to solve the above-mentioned problems.

That is, the fluorescent X-ray analysis apparatus according to the present invention comprises a sample type detecting means for detecting the type of sample, an atmosphere detecting means for detecting the atmosphere in the analysis chamber in which the sample is housed, and both the detecting means. Based on the detection output by
It is provided with an alarm means for determining whether or not the type of sample and the atmosphere are compatible and, if they are not compatible, determining that an abnormality has occurred and issuing an alarm.

[0010]

In the above structure, the sample type detecting means detects the type of sample such as whether the sample to be analyzed is a liquid or a solid. In addition, the atmosphere detecting means detects the atmosphere state such as whether the atmosphere in the analysis chamber in which the sample is stored is atmospheric pressure or vacuum. Then, the alarm means determines whether or not the type of the sample and the atmosphere are compatible with each other, based on the detection outputs of both the detection means. In the case of non-conformity, it is considered that an abnormality has occurred and an alarm is issued.

Therefore, when an alarm is issued, an atmosphere which is not compatible with the type of the sample, such as a solid sample, which is kept at atmospheric pressure, or a liquid sample, which is evacuated, is used. Since the analysis is started below, the operator can start the analysis after adjusting the atmosphere in the irradiation chamber to an atmosphere suitable for the type of sample.

[0012]

1 is a block diagram of an X-ray fluorescence analyzer according to an embodiment of the present invention.

In the figure, 1 is the whole of the fluorescent X-ray analysis apparatus, 2 is the apparatus main body, and 4 is the sample transport mechanism.

The apparatus main body 2 has a hollow analysis chamber 4, and an irradiation chamber 8 and a sample chamber 10 are formed in the analysis chamber 4 above and below the partition wall 6, respectively.
The partition wall 6 is provided with a shutter 12 for communicating and blocking both chambers 8 and 10. Then, in the irradiation chamber 8, an X-ray tube 14 for irradiating the sample with primary X-rays and a spectroscope 16 for separating the fluorescent X-rays from the sample are installed facing each other, and the atmosphere in the irradiation chamber 8 An atmospheric pressure sensor 18 is attached as an atmosphere detecting means for detecting. In addition, a sample insertion port 20 is formed in the lower part of the sample chamber 10 so as to open downward.

On the other hand, the sample transport mechanism section 4 has a fixed circular table 22, and a pulse motor 26 is attached to the lower portion of the fixed circular table 22.
Drive shaft 28 penetrates the fixed circular table 22 upward,
The rotary circular table 30 is attached to the penetrating portion. In the case of the present example, the rotary circular table 30 is such that the outer peripheral edge portions at the point-symmetrical positions with respect to the drive shaft 28 are both cut out into a substantially semicircular shape, and the locking portions 32 are respectively provided.
Is formed, and each of the sample containers 3 to be described later is attached to these hook portions 32.
4a or 34b is loaded. Further, below the sample chamber 10, a lift mechanism 36 for moving up and down the sample container 34a or 34b along a vertical axis passing vertically through the sample insertion port 20 is arranged. In this lift mechanism 36, a receiving seat 40 for the sample container 34a or 34b is attached to the upper end portion of an elevating shaft 38, and the lift mechanism 36 is raised to place the sample container 34a or 34b in the sample chamber 10. At
The seat 40 hermetically seals the sample insertion port 20.

Further, the fixed circular table 22 has
The insertion hole 42 of the lift mechanism 36 is formed, and a micro switch 44 as sample type detection means for detecting the type of sample is provided at a position symmetrical with respect to the insertion hole 36 about the drive shaft 28.

The reference numeral 46 determines whether or not the type of sample and the atmosphere match based on the detection outputs from the atmospheric pressure sensor 18 and the microswitch 44. If they do not match, it is considered that an abnormality has occurred. Is an alarm means for issuing an alarm. In the case of this example, the alarm means 46 comprises an exclusive OR circuit 48 and an alarm device 50 such as a lamp or a buzzer for alarming abnormality based on the output of the circuit 48.

Reference numeral 52 denotes a drive circuit for driving the pulse motor 26, and reference numeral 54 denotes a drive circuit 52 from a CPU (not shown) to the drive circuit 52 only when the alarm means 46 determines that the analysis state is normal. It is an AND gate for allowing the output of a given control pulse.

FIG. 2 is a partially enlarged sectional view of the sample transport mechanism section 4 of FIG.

FIG. 1A shows a state in which a liquid sample container 34a used when analyzing a liquid sample Sa is placed on the fixed circular table 22.
4a has a cylindrical outer case 56, and the outer case 5
An X-ray transmission hole 58 is formed at the upper end of 6, and the X-ray transmission hole 58 is sealed with a mylar film 60 made of polyester or the like. A tubular inner case 62 made of Teflon or the like is arranged inside the outer case 56, and a bottom lid 64 is screwed to the lower portion. The bottom lid 64 is screwed in this state. The lower surface and the lower surface of the outer case 56 are flush with each other. The inside of the inner case 62 is filled with the liquid sample Sa. In addition, 70 is an O-ring.

On the other hand, FIG. 2B shows a state in which a solid sample container 34b used when analyzing a solid sample Sb is arranged on the fixed circular table 22, and this sample container 34b is shown in FIG. , A cylindrical case 72, an X-ray transmission hole 74 is formed at the upper end of the case 72, and a bottom lid 76 is screwed to the lower end of the case 72. The lower surface of the lid 76 is located above the lower surface of the case 72 by a predetermined height h. Then, inside the case 72, the solid sample Sb, the pressing plate 78, and the compression spring 80 are arranged.
By 0, the sample Sb is pressed and fixed in the case 72 while facing the X-ray transmission hole 74.

Next, the operation of the X-ray fluorescence analyzer 1 having the above structure will be described.

(1) When the type of sample matches the atmosphere in the analysis chamber For example, when a liquid sample Sa is analyzed, the sample container 34a for liquid is rotated as shown in FIG. 2 (a). The circular table 30 is arranged on the fixed circular table 22 through the hooking portions 32. At this time, the lower surface of the bottom lid 64 and the outer case 56
Since the lower surface of the sample container 34 is flush with the lower surface of the sample container 34,
The micro switch 44 located below a is turned on, whereby a high level signal is output from the micro switch 44. Further, in the analysis of the liquid sample Sa, the inside of the irradiation chamber 8 of the analysis chamber 4 of the apparatus main body 2 is held in He gas or air atmosphere, and in this state, the atmospheric pressure is obtained. Therefore, the atmospheric pressure sensor 18 outputs a high-level signal indicating the atmospheric pressure state. Then, both the output of the micro switch 44 and the output from the atmospheric pressure sensor 18 are input to the alarm means 46.

When a high level signal is input to the exclusive OR circuit 48 of the alarm means 46 as described above, the sample is a liquid and the atmosphere in the analysis chamber 4 is at atmospheric pressure. Since the analysis conditions are met, the output becomes low level, and the alarm 50 is not issued.

When the solid sample Sb is analyzed,
As shown in FIG. 2B, the sample container 34b for solid is placed on the fixed circular table 22 through the hook 32 of the rotary circular table 30. At this time, since the lower surface of the bottom cover 64 is lifted from the lower surface of the outer case 56 by a predetermined height h, the micro switch 44 located below the sample container 34b is turned off, which causes the micro switch 44 to move away from the micro switch 44. Outputs a low level signal. Further, in the analysis of the solid sample Sb, the inside of the irradiation chamber 8 of the analysis chamber 4 of the apparatus main body 2 is kept in a vacuum atmosphere. Therefore, the atmospheric pressure sensor 18 outputs a low level signal indicating a vacuum state. Then, both the output of the micro switch 44 and the output from the atmospheric pressure sensor 18 are input to the alarm means 46.

When a low level signal is input to the exclusive OR circuit 48 of the alarm means 46 as described above, it means that the sample is solid and the atmosphere in the analysis chamber 4 is vacuum. Since the analysis conditions are met, the output becomes low level, and the alarm 50 is not issued.

When the output of the exclusive OR circuit 48 is at the low level, the gate of the AND gate 54 is opened, so that the control pulse from the CPU (not shown) is supplied to the drive circuit 5.
Join 2 Therefore, the drive circuit 52 activates the pulse motor 26 to rotate the rotary circular table 30 so that the sample container 34a or 34b is lifted.
Moved to the side. Then, when the lift mechanism 36 moves up, the sample container 34a or 34b is placed in the sample chamber 10 and the analysis is started.

(2) When the type of sample and the atmosphere in the analysis chamber do not match: Even though it is a liquid sample Sa, it remains in the atmospheric pressure state,
Alternatively, in the case where the type of the sample and the atmosphere do not match, such as when the solid sample Sb is evacuated, one input of the exclusive OR circuit 48 of the alarm means 46 is at the high level and the other input is at the other level. Input goes low. Therefore, since the type of sample and the atmosphere in the analysis chamber 4 do not match, the output becomes high level, and the alarm 50 issues an alarm. Then, when there is an alarm, the sample containers 34a or 34b are exchanged, or the atmosphere is changed to suit the type of sample.

When the output of the exclusive OR circuit 48 is at a high level, the gate of the AND gate 54 is closed, so that the control pulse from the CPU (not shown) is supplied to the drive circuit 52.
Do not join. Therefore, the rotary circular table 30 is not rotated, and the sample container 34a or 34b is not moved to the lift mechanism 36 side.

In this embodiment, for convenience of explanation, the rotary circular table 30 is shown with the hook 32 of the sample container 34a or 34b formed at the position symmetrical with respect to the drive shaft 28. However, the present invention is not limited to this, and a plurality of hook portions 32 may be formed along the outer peripheral edge of the rotary circular table 30 at a predetermined pitch. In this case, the type of the sample hooked on the hooking portion 32 immediately before from the position directly below the lift mechanism 36 may be determined.

[0031]

According to the present invention, an atmosphere that is not compatible with the type of sample, such as a solid sample that is kept at atmospheric pressure, or a liquid sample that is evacuated, is used. When the analysis is started, the incompatibility is notified to the analyst by the alarm, so that the error of the analyst is surely avoided, and the proper analysis result is always obtained.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an X-ray fluorescence analyzer according to an embodiment of the present invention.

FIG. 2 is a partially enlarged sectional view of FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Fluorescent X-ray analysis device, 2 ... Device main body part, 4 ... Sample conveyance mechanism part, 18 ... Atmosphere detection means, 44 ... Sample type detection means, 46 ... Alarm means.

Claims (1)

[Claims] 1. A sample type detection means for detecting the type of sample, an atmosphere detection means for detecting the atmosphere in an analysis chamber in which the sample is stored, and a sample type detection means based on the detection outputs of both detection means. An X-ray fluorescence analysis device comprising: an alarm unit that determines whether or not the atmosphere matches, and if not, considers that an abnormality has occurred and issues an alarm.