JP2762269B2 - X-ray generation control mechanism of X-ray fluorescence analyzer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluorescent X-ray tube for controlling an X-ray tube for irradiating a sample with primary X-rays.
The present invention relates to an X-ray generation control mechanism of the X-ray analyzer.

[0002]

2. Description of the Related Art In a conventional fluorescent X-ray analyzer, on / off control of an X-ray tube for irradiating a sample on a sample stage with primary X-rays is usually performed to prevent leakage of X-rays. Along with the opening / closing operation of the shutter, the operation is performed in conjunction with the opening / closing operation of a shield cover for forming the sample chamber in an airtight state. When the shield cover is closed, the shutter opens and high-voltage power is supplied to the X-ray tube. It was like.

[0003]

As described above, conventionally, the on / off control of the X-ray tube is linked with the opening / closing operation of the shield cover. Therefore, when the shield cover is closed, the X-ray is always emitted. Had occurred.

[0004] Therefore, the X-ray tube sometimes generates useless X-rays, the X-ray tube is not sufficiently protected, and extra fluorescent X-rays are absorbed by the detector (proportional counter tube). In some cases, the deterioration of the detector may be accelerated.

The present invention has been made in view of such circumstances,
An object of the present invention is to control on / off of an X-ray tube so as not to generate useless primary X-rays.

[0006]

According to the present invention, means for achieving the above-mentioned object are constituted as follows. That is, in the first invention, high-voltage power is supplied to the X-ray tube.
High-voltage control means that activates the high-voltage generation circuit starts measurement
The high-voltage control means activates the high-voltage generation circuit only when the shield cover, which is activated by an ON signal from the switch and forms the sample chamber in an airtight state, is closed and the shutter for preventing X-ray leakage is open. The X-ray tube is configured to be activated to supply high-voltage power to the X-ray tube.

In the second invention, high-voltage power is supplied to the X-ray tube.
The high-voltage control means that operates the high-voltage generation circuit
Activated by the ON signal from the fixed start switch, the shield cover for forming the sample chamber in an airtight state is closed, and X
Only when the shutter for preventing the leakage of the wire is opened and the degree of vacuum in the sample chamber is equal to or higher than a predetermined value,
The high-voltage control means is configured to operate a high-voltage generating circuit to supply a high-voltage power to the X-ray tube.

[0008]

In the first invention, high-voltage power is supplied to the X-ray tube only when the measurement start switch is turned on, the shield cover is closed, and the shutter for preventing X-ray leakage is open. Therefore, even if the shield cover is closed, if the measurement start switch is not turned on, the primary X-ray is not irradiated, and generation of useless primary X-ray is prevented.

[0009] In the second aspect of the present invention, unless turned on further degree of vacuum Tokoro Tei以 in the sample chamber (e.g. 1torr or less), the primary X-ray is not irradiated. Therefore, in the process of evacuation, even if the shield cover is closed and the shutter is open, no primary X-ray is generated, and the generation of useless primary X-rays can be more effectively prevented.

[0010]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows a fluorescent X-ray analyzer 1 (FIGS. 4 and 5).
FIG. 4) is a block diagram of the X-ray generation control mechanism of FIG.
A measurement start switch 2 provided in a computer 30 separately connected to the X-ray analyzer 1, a shield cover close sensor 6 for detecting a closed state of a shield cover 4 for forming the sample chamber 5 in an airtight state, and an X-ray A shutter open sensor 8 for detecting an open state of the shutter 7 for preventing leakage is connected to the input side of the high-pressure control means 9, and the output side thereof has a primary X-ray sensor for the sample on the sample stage 10. high voltage generating circuit 12 to supply a high voltage power supply is connected to the X-ray tube 13 for irradiating the line X. Note that, in FIG.
a is a window opened on the sample stage 10.

The high-pressure control means 9 is activated by an ON signal from the measurement start switch 2 and only when the shield cover 4 is closed and the shutter 7 is open,
Activate the high voltage generation circuit 12 to supply a high voltage power to the X-ray tube 13.
It is configured to supply .

As shown in FIG. 4, the above-mentioned shutter 7 has a V-shaped cross section, and is rotated by a rotary solenoid 15 via a link mechanism 15a in the direction of an arrow along a V-groove formed below the sample stage 10. In the closed state indicated by the two-dot chain line, the primary X-ray X irradiated from the X-ray tube 13 toward the sample at one side 7a, and the detector 14 from the sample at the other side 7b. The shutter open sensor 8 detects the open state indicated by the solid line for blocking the fluorescent X-rays FX emitted toward the shutter and releasing the cutoff.

On the other hand, the lower part of the shield cover 4 is O
Closely around the sample stage 10 via the ring, the sample chamber 5
Is formed in an airtight state, and the closed state is determined by a shield cover closing sensor 6 provided on the base plate 16 of the apparatus main body 3.
Is detected by A hose 19 connected to a pump 18 is connected to the sample chamber 5, and the inside of the sample chamber 5 is regulated to a vacuum state with the shield cover 4 closed, and the degree of vacuum is measured by a vacuum gauge 20 (FIG. 5).

A locking member 23 constituting locking means 22 is fixed to the front of the shield cover 4. When the shield cover 4 is closed, a locking member 24 provided at the front of the apparatus body 3 is provided. Thereby, the hooked member 23 is locked. Specifically, the locking member 24 is locked by a spring 25 in the locking direction (left direction).
When the shield cover 4 is opened, it comes into contact with the stopper 26 and is set to the unlocked position.
When the shield cover 4 is closed, the stopper 26 is pushed down by the hooked member 23, and the hooking member 24 moves in the locking direction by the bias of the spring 25, and the hooked member 23 is hooked and the shield cover 4 is moved. The sample chamber 5 is locked, and the inside of the sample chamber 5 is made airtight. To release the lock, the lever 27 attached to the latch member 24 may be moved rightward. When the operation of the lever 27 is detected by the limit switch 29, the rotary solenoid 15
Is operated to move the shutter 7 to the closed position, and thereafter, the lock on the shield cover 4 is released and the sample chamber 5 is opened. In FIG. 4, reference numeral 28 denotes a limit switch for detecting the unlocked position of the locking member 24.

The basic flow of the on / off control of the X-ray tube 13 having such a configuration is shown in FIGS.
First, the shield cover 4 is opened (S1), and the sample is placed on the sample stage 10 (S2).
Thereafter, the shield cover 4 is closed (S3). Next, when the measurement start switch 2 is turned on (S4), the high-voltage control
Stage 9 is activated (S5), control is performed after S6
You .

Then, the shield cover closing sensor 6
After the closed state of the shield cover 4 is confirmed by the close detection signal (S6), the open detection signal from the shutter open sensor 8 is transmitted.
When the open state of the shutter 7 is confirmed by the signal (S
7) The high voltage generation circuit 12 is operated by the high voltage control means 9
Then, high-voltage power is supplied to the X-ray tube 13 (S8),
A line X is irradiated on the sample.

Therefore, even if the shield cover 4 is closed, if the measurement start switch 2 is not turned on and the shutter 7 is not opened, the primary X
No X-rays are generated, so that the useless primary X-rays X are prevented from being generated, and no extra fluorescent X-rays FX are incident on the detector 14, so that the X-ray tube 13 and the detector 14 are deteriorated. Can be suppressed.

[0018] Figures 6 and 7 show different embodiments, high
A vacuum gauge 20 is also connected to the input side of the pressure control means 9 in addition to the shield cover close sensor 6 and the shutter open sensor 8,
The degree of vacuum in the sample chamber 5 is Tokoro Tei以, i.e. those indicated value of the vacuum gauge 20 was a requirement for activating the high voltage control unit 9 also to be equal to or less than 1 torr.

With this configuration, when the inside of the sample chamber 5 is not reduced to 1 torr or less even when the shield cover 4 is closed and the shutter 7 is opened when the sample chamber 5 is evacuated. No primary X-ray X is generated,
The generation of useless primary X-rays X during the evacuation process is prevented. Therefore, it is possible to more effectively suppress deterioration of the X-ray tube 13 and the detector 14 due to wear.

[0020]

As described above, according to the first aspect of the present invention, X-rays are generated only when there is an ON signal from the measurement start switch, the shield cover is closed, and the shutter is open. Therefore, even if the shield cover is closed, if the measurement start switch is not turned on, the primary X-ray will not be emitted, and the occurrence of useless primary X-rays will be prevented, and the X-ray tube and detection It is possible to effectively suppress the wear deterioration of the vessel.

[0021] According to the second invention, to become the degree of vacuum in the sample chamber Tokoro Tei以 (e.g. 1torr or less), since the requirement for starting the high-pressure control means,
In the process of evacuation, even if the shield cover is closed and the shutter is open, it is possible to prevent generation of primary X-rays, and it is possible to more effectively prevent generation of useless primary X-rays.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an entire configuration of an embodiment of the first invention.

FIG. 2 is the first half of the basic control flow.

FIG. 3 is a latter half of the basic control flow.

FIG. 4 is a perspective view of a shutter structure of the X-ray fluorescence spectrometer.

FIG. 5 is an overall perspective view of the fluorescent X-ray analyzer.

FIG. 6 is a block diagram showing an entire configuration of an embodiment of the second invention.

FIG. 7 is a latter half of the basic control flow.

[Explanation of symbols]

2 ... Measurement start switch, 4 ... Shield cover, 5 ... Sample chamber, 7 ... Shutter, 9 ... High pressure control means , 13 ... X-ray tube.

Claims (2)

(57) [Claims] 1. A high voltage for supplying a high voltage power to an X-ray tube.
The high-voltage control means for operating the generating circuit is a measurement start switch
It is started by the ON signal from the closed shielding cover forming a sample chamber in an airtight state, and only when the shutter for preventing the X-ray leakage is opened, the high
An X-ray generation control mechanism for a fluorescent X-ray analyzer, wherein a high-pressure power supply is supplied to said X-ray tube by operating a high-pressure generating circuit by a pressure control means . 2. A high voltage for supplying a high voltage power to an X-ray tube.
The high-voltage control means for operating the generating circuit is a measurement start switch
Is activated by an ON signal from the controller, the shield cover for forming the sample chamber in an airtight state is closed, and a shutter for preventing leakage of X-rays is opened, and when the degree of vacuum in the sample chamber becomes a predetermined value or more. Only the high pressure control hand
The stage activates a high-voltage generating circuit, and a high-voltage power is supplied to the X-ray tube.
Fluorescent X characterized in that it is configured to be supplied
X-ray generation control mechanism of the X-ray analyzer.