JP3262832B2 - Goniometer for X-ray diffractometer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a goniometer used for rotating a sample and an X-ray detector at a constant angular velocity for X-ray diffraction measurement in an X-ray diffraction apparatus.

[0002]

2. Description of the Related Art Generally, in an X-ray diffraction apparatus, an operation is performed in which an X-ray is incident on a sample and the X-ray diffracted by the sample is detected by an X-ray detector. During the operation, the sample rotates intermittently or continuously around the sample central axis at a constant angular velocity, and the X-ray detector intermittently moves in the same direction about the sample central axis at an angular velocity twice the angular velocity of the sample. Rotate periodically or continuously. Usually, such rotation of the sample is called θ rotation, and rotation of the X-ray detector is called 2θ rotation. The goniometer is used as a so-called goniometer for rotating the sample by θ and rotating the X-ray detector by 2θ.

Conventionally, in a goniometer, a sample is supported by a .theta. Rotation axis, which is a cylindrical shaft member, and an X-ray detector is supported by a 2.theta. Rotation axis coaxial with the .theta. Rotation axis. The sample is rotated by θ by rotating each of the rotation axes, and the X-ray detector is further rotated by 2θ. Usually, the θ rotation axis and the 2θ rotation axis are driven by a pulse motor.

Incidentally, an X-ray source that emits X-rays toward a sample supported on a θ-rotation axis of a goniometer includes a sealed tube X-ray generator, a rotating anti-cathode X-ray generator, and various other types. There are things. The sealed tube type X-ray generator is an X-ray generator of a type in which a fixed target is provided in a closed vacuum container that cannot be opened, and electrons collide with the fixed target to emit X-rays therefrom. A rotating anti-cathode X-ray generator is a type of X-ray generator in which a rotating target that rotates at high speed is provided in an openable closed vacuum vessel, and electrons collide with the rotating target to emit X-rays therefrom. is there.

In general, different types of X-ray sources have different X-ray emission angles. For example, a sealed tube X-ray generator emits X-rays at an angle of 6 ° (minus 6 °) downward, while a rotating anti-cathode X-ray generator emits X-rays at an angle of 6 ° (plus 6 °). X-rays are emitted at the angle of ゜). When the emission angle of the X-ray emitted from the X-ray source is different, the angular position of the goniometer with respect to the X-ray source must be changed accordingly. If the relative angle between the two does not match the predetermined angle, the optical axis of the X-ray emitted from the X-ray source does not match the optical axis of the X-ray optical system mounted on the goniometer, and accurate X-ray diffraction measurement can be performed. You will not be able to do it.

In a conventional X-ray diffractometer, a relative angle between an X-ray source and a goniometer is adjusted to a predetermined angle.
A dedicated goniometer has been combined for each type of X-ray source.

[0007]

As described above, various types of X are used.
If you combine a dedicated goniometer with the source, you must prepare many types of goniometers beforehand.
There has been a problem that various desired X-ray diffraction measurements cannot be performed. This has been a very large expense for the measurer. In addition, manufacturing a goniometer of a different model in accordance with the type of X-ray source greatly complicates the manufacturing process of the X-ray diffraction apparatus.

The present invention has been made to solve the above-mentioned conventional problems, and has as its object to provide a goniometer that can be commonly used for various X-ray sources.

[0009]

A goniometer for an X-ray diffractometer according to the present invention is a goniometer for an X-ray diffractometer used for an X-ray diffractometer having an X-ray generator,
Rotation axis supporting sample and 2θ supporting X-ray detector
A goniometer for an X-ray diffraction apparatus having a rotation axis and rotating the θ rotation axis and the 2θ rotation axis about a sample central axis, wherein the θ rotation axis and the 2θ
A base housing that stores a rotation axis and is rotatably attached to the base around the sample center axis, and gonio fixing means that fixes the base housing to the base so as to be immovable with respect to the base. Height adjusting means for adjusting the height of the base, wherein the base housing is provided separately from the X-ray generator.

[0010]

An X-ray source is attached to a goniometer for an X-ray diffractometer, and X-rays emitted from the X-ray source are incident on a sample supported by a θ rotation axis. The X-ray diffracted by the sample is detected by an X-ray detector supported by a 2θ rotation axis. There are various types of X-ray sources, and the X-ray emission height and the X-ray emission angle of these various X-ray sources are different from each other. When the type of X-ray source used is variously different, the base housing is rotated at an appropriate angle about the sample center axis with respect to the base, and this rotation causes the light of the X-ray optical system mounted on the base housing to rotate. The axis is matched to the X-ray emission angle of the X-ray source used. Then, in this state, the base housing is fixed to the base by the gonio fixing means so as not to move. Thus, by preparing only one common goniometer, it becomes possible to configure an X-ray diffraction measurement system adapted to many different types of X-ray sources.

[0011]

FIG. 1 shows a case where the present invention is applied to a goniometer of a type in which a diffraction surface including both an incident X-ray incident on a sample and a diffracted X-ray diffracted by the sample extends in a vertical direction, that is, a so-called vertical goniometer. Is shown. A goniometer indicated by reference numeral 1 is a rectangular parallelepiped base housing 3.
And a cylindrical θ inside the base housing 3.
A rotating shaft 9 and a similarly cylindrical 2θ rotating shaft 10 are provided coaxially with each other.

The inner surface of the right side wall of the base housing 3 and the θ rotation axis 9
, Between the θ rotation shaft 9 and the 2θ rotation shaft 10, and between the annular ring screw 11 screwed to the left side wall of the base housing 3 and the 2θ rotation shaft 10, respectively. 12 are provided. This wire bearing is a thrust ball bearing formed by using annular metal wires as the inner ring and the outer ring and interposing a number of metal balls between the wires. The ring screw 11 is tightly tightened in the direction of the 2θ rotation shaft 10, so that the 2θ rotation shaft 10 and the θ rotation shaft 9 cannot be moved in the vertical and horizontal directions but can rotate about the central axis ω by the tightening force. Are stored inside the base housing 3.

A gear 9a is provided on the outer peripheral surface of the right end of the θ rotation shaft 9, and a worm 13 meshes with the gear 9a. On the other hand, another gear 10a is provided on the outer peripheral surface of the right end portion of the 2θ rotation shaft 10, and another worm 14 meshes with the gear 10a. As shown in FIG.
The shaft-side worm 13 is provided on an output shaft of a pulse motor 15 fixed to an upper portion of a right side wall of the base housing 3. The worm 14 on the 2θ-axis side is provided on the output shaft of another pulse motor 16 fixed to the lower part of the right side wall of the base housing 3. With this structure, when the θ-axis side pulse motor 15 operates, the θ rotation shaft 9 rotates about the center axis ω, and when the 2θ axis side pulse motor 16 operates, the 2θ rotation shaft 10 also rotates about the center axis ω. .

In FIG. 1, a θ-rotation table 17 is fixed to the left end of the θ-rotation shaft 9 by bolts (not shown) or the like. The θ-rotation table 17 is formed by a three-stage cylindrical member, and the lower left end portion of the leftmost small-diameter cylindrical portion is notched. A leaf spring 18 is fixed to the side wall of the notch, and a sample holder 19 which is a rectangular plate material is provided between the leaf spring 18 and the tip of the θ-rotation table 17 as shown in FIG. Attached, that is, inserted. A rectangular hole is provided at the tip of the sample holder 19, and a sample 20 to be measured is packed in the hole.

In FIG. 1, at the left end of the 2θ rotation axis 10,
A disk-shaped 2θ turntable 21 is fixed by bolts 22. As shown in FIG. 2, a detector arm 23 extending rightward is fixed to the right end of the 2θ turntable 21, and a light receiving slit box 25 containing a light receiving slit 24 is mounted on the detector arm 23. And X-ray detector 26
Has been fixed. A support base 27 is fixed to a lower left portion of the base housing 3 by three bolts 28,
A prismatic column 29 integrated with the column base 27 extends in parallel with the θ-turntable 17. A divergence slit box 31 containing a divergence slit 30 is provided at the tip of the support 29.

In FIG. 1, a gonio rotating shaft 4 which is a cylindrical tubular member is fixed to a right side wall of a base housing 3 by bolts (not shown) or the like. The gonio rotation shaft 4 is
It is inserted into a through hole 6 provided in advance on the base 2 constituted by a rigid member having an L-shaped cross section, and two lock nuts 7 and 8 are provided on a threaded portion provided at the tip of the gonio rotary shaft 4. Are engaged. The base housing 3 is attached to the left wall surface of the base 2 so that the base housing 3 can rotate about the central axis ω by tightening the lock nuts 7 and 8. A bearing 32 is provided between the outer peripheral surface of the gonio rotary shaft 4 and the inner peripheral surface of the base through hole 6 so that the base housing 3 can rotate smoothly. A bearing 33 is also provided between them.

The base 2 is mounted on a table 40 via four grounding feet 39. These grounding feet 39 can be independently extended and retracted with respect to the base 2, and the height of the base 2, that is, the height of the goniometer 1 can be changed by appropriately adjusting the amount of expansion and contraction. Can be.

FIG. 3 shows the base 2 according to the arrow III in FIG.
The back of is shown. As shown in FIG. 3, the base 2 is provided with two arc-shaped long holes 34, 34 at positions symmetrical with respect to the gonio central axis ω. Bolts 35 are inserted into these elongated holes one by one, and as shown in FIG. 1, the bolts 35 are fitted into screw holes provided in the right side wall of the base housing 3. By strongly tightening the bolts 35, the whole of the base housing 3, that is, the entire goniometer 1 is fixed to the base 2 so as not to move.

As shown in FIG. 2, on the left side of the goniometer 1, an enclosed tube type X-ray generator 38 having a fixed target 36 and a filament 37 arranged opposite thereto.
Are arranged. This sealed tube type X-ray generator 38
Has a structure in which the internal Q set in a vacuum state cannot be opened. In this sealed tube type X-ray generator, electrons generated from the filament 37 collide with the fixed target 36, and the target 36 emits X-rays R. Normally, in a sealed tube type X-ray generator, X-rays are emitted downward at an angle of 6 ° (minus 6 °). In the state of FIG. 2, the mounting angle of the base housing 3 with respect to the base 2 and the base angle are set so that the X-rays R emitted from the sealed tube X-ray generator 38 at an angle of 6 ° downward enter the sample 20 accurately. The height of the table 2 from the table 40 is adjusted.

The operation of the X-ray diffraction device having the above configuration will be described below. In FIG. 2, after the X-rays emitted from the sealed tube X-ray generator 38 are restricted by the divergence slit 30, the sample 20 in the sample holder 19 is
(See FIG. 4). When a predetermined X-ray diffraction condition is satisfied between the incident X-ray and the crystal lattice plane in the sample, X-ray diffraction occurs in the sample. The X-ray diffracted by the sample is
The light is condensed on the light receiving slit 24 and is thereafter detected by the X-ray detector 26. An X-ray intensity measurement circuit (not shown) is electrically connected to the subsequent stage of the X-ray detector 26, and the intensity of the diffracted X-ray is measured by the measurement circuit.

At the time of the X-ray intensity measurement, the θ-turntable 17 is driven by the θ-axis side pulse motor 15 so that the center axis ω
Rotate intermittently or continuously about. Also, 2
turntable 21 is driven by a 2θ-axis side pulse motor 16 and intermittently or continuously rotates 2θ about the central axis ω at twice the angular velocity of the θ turntable 17. By the θ rotation of the θ-rotation table 17, the sample 20 supported thereon is also rotated by θ, and by the 2θ rotation of the 2θ-rotation table 21, the light receiving slit 24 and the X-ray detector 26 supported thereon are rotated.
Rotates 2θ. The X-ray detector 26 detects diffracted X-rays from the sample 20 at each angular position during the 2θ rotation.

The X-ray generator used in the X-ray diffractometer is the sealed tube type X-ray generator 3 exemplified in the above embodiment.
The X-ray generator is not limited to 8, and various types of X-ray generators may be used as needed. For example, as shown in FIG. 5, the rotating target 47 and the filament 3
Rotary anti-cathode type X-ray generator 4 containing vacuum chamber 7 in vacuum chamber Q
8 is also often used. In this rotary anti-cathode X-ray generator 48, the vacuum chamber Q inside can be opened, and the X-ray R emitted from the rotary target 47 travels upward at an angle of 6 °.

Such a rotating anti-cathode X-ray generator 48
When the goniometer 1 is attached to the base 2 with the angle of attachment of the goniometer 1 kept at a position compatible with the sealed tube X-ray generator shown in FIG. 2, the optical axis of the X-ray incident on the sample and the X-ray on the goniometer are Since the optical axes of the line optical system do not match, X-ray diffraction measurement cannot be performed. Therefore, the following operation is performed in the goniometer according to the present embodiment.

First, in FIG. 1, the two bolts 35 fixing the base housing 3 of the goniometer to the base 2 are loosened so that the base housing 3 can be rotated with respect to the base 2. After that, the whole of the base housing 3, that is, the entire goniometer 1 is rotated by an appropriate angle about the center axis ω,
Adjustment is performed so that the X-ray optical axis R and the optical axis of the gonio optical system match (FIG. 5). When the height of the goniometer 1 also needs to be adjusted, the adjustment can be performed by extending and contracting the ground contact foot 39 with respect to the base 2. When the optical axis is set to the correct position, the bolt 35 (FIG. 1) is tightened again in that state, and
The base housing 3 is fixed to the base 2 so as not to move. By the above operation, X-ray diffraction measurement using the rotating anti-cathode X-ray generator 48 can be performed. By the same operation, the optical axis of the X-ray optical system on the goniometer can be set at any desired position for any X-ray generators having different X-ray emission angles and emission heights.

Although the present invention has been described with reference to one embodiment, the present invention is not limited to the embodiment. For example, the method for rotatably attaching the base housing 3 to the base 2 is not limited to the structure using the cylindrical gonio rotation shaft 4 and the double lock nuts 7 and 8 shown in FIG. Any structure can be adopted. The gonio fixing means for fixing the base housing 3 to the base 2 so as to be immovable is not limited to the structure including the elongated holes 34 and the bolts 35 provided in the base 2, and any other structure can be adopted. Further, various types of X-ray sources, that is, X-ray generators, which can be used for the goniometer are considered in addition to the sealed tube X-ray generator and the rotary anti-cathode X-ray generator.

[0026]

According to the present invention, one goniometer can be commonly used for various X-ray sources having different X-ray emission angles and X-ray emission heights. The device can be manufactured at low cost. In addition, on the side of the measurer, various types of X-rays having different X-ray
Line diffraction measurements can be performed.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing an embodiment of a goniometer for an X-ray diffraction apparatus according to the present invention.

FIG. 2 is a front view of the goniometer according to an arrow II in FIG. 1;

FIG. 3 is a rear view of the goniometer according to an arrow III in FIG. 1;

FIG. 4 is an enlarged perspective view showing a sample holding section of the goniometer.

FIG. 5 is a front view showing a state where an X-ray source is changed to another type in the X-ray measurement system of FIG. 2;

[Explanation of symbols]

 Reference Signs List 2 base 3 base housing 4 gonio rotating shaft 6 through hole in base 7 lock nut 8 lock nut 9 θ rotation axis 10 2θ rotation axis 20 sample 26 X-ray detector 30 divergence slit 34 long hole in base 35 bolt ω sample Center axis

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-3-289548 (JP, A) JP-A-1-156643 (JP, A) JP-A-2-201255 (JP, A) JP-A-3-206 287054 (JP, A) JP-A-1-127940 (JP, A) JP-A-5-223991 (JP, A) JP-A-5-223995 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G21K 1/06 G01N 23/20

Claims (3)

(57) [Claims] 1. A goniometer for an X-ray diffractometer used in an X-ray diffractometer having an X-ray generator, comprising: a θ rotation axis supporting a sample; and 2θ supporting an X-ray detector.
A goniometer for an X-ray diffraction apparatus having a rotation axis and driving the θ rotation axis and the 2θ rotation axis to rotate about a sample central axis, wherein the θ rotation axis and the 2θ rotation axis are stored. A base housing rotatably attached to the base around the sample center axis, gonio fixing means for fixing the base housing in a position-immovable manner with respect to the base, and a height of the base. A height adjusting means for adjusting , wherein the base housing is provided separately from the X-ray generator, wherein the goniometer for an X-ray diffraction apparatus is provided. 2. A goniometer for an X-ray diffraction apparatus according to claim 1, wherein said gonio fixing means has a bolt attached to said base housing and an elongated hole for guiding the movement of said bolt. . 3. The gonio rotation shaft according to claim 1 or 2, wherein the gonio rotation shaft is provided protruding from the base housing and has a cylindrical central axis with the sample central axis as a central axis. A nut, and a through-hole provided in the base and capable of inserting the gonio-rotating shaft, wherein the gonio-rotating shaft is inserted into the through-hole, and a tip end of the gonio-rotating shaft inserted. The goniometer for an X-ray diffractometer, wherein the base case is rotatably attached to the base by fastening the base to the base with the nut.