DE7524740U - X-ray goniometer - Google Patents

Description

August 4th 1975 9654-75 / Dr.ν.B. / Ba

PATENT LAWYERS DH. ING. ERNST SOMMERFELD _ 7 Λ //

DR.DIETER V. BEZOLD T h> Z- ^ r / ( / ''

DIPL. IN O. PETER SCHÜTZ -4 DIPL. ING. WOLFGANG HEUSLElt DS MUENCHEN 80

MARIA-THBRBSIA-BTRASSE SS POSTiAOH ββΟβββ

Max Planck Society for the Promotion of

Sciences e.V. 3400 Göttingen, Eunsenstrasse 10

X-ray goniometer

A known X-ray Präzessionsgoniometer includes a serving for holding a sample in a Primärstrahiengang goniometer head that is mounted on an adjustable about its axis wool, a receiving material holder, a Präzessionsgetriebe for pivoting the receiving holder and a drive motor for driving the Präzessionsgetriebes. Precession goniometers of this type enable an undistorted reproduction of the reciprocal lattice of a single crystal.

There are also devices for X-ray fine structure analysis known, which work according to the Bragg or rotary crystal method and are often referred to as "rotation cameras". With such rotating crystal or rotation recordings, the sample is rotated in a monochromatic X-ray beam around the so-called To determine glancing angle.

7524740 29.0176

It was previously not possible with a single device both To make precession recordings as well as rotation recordings. It was therefore necessary to examine the sample in two different devices and adjust twice for this. Quite apart from the fact that this is tedious and time-consuming, they are exactly comparable Measurement results not guaranteed.

The present invention is accordingly based on the object of further developing an X-ray precession goniometer so that that it can also be used to make rotary crystal or rotation recordings.

This object is achieved by the invention which is protected in claim 1.

With the X-ray goniometer according to the invention, precession and rotation recordings can be made under exactly the same conditions and manufacture in a short time.

An exemplary embodiment of the invention is explained in more detail below with reference to the drawing, which also include Still other features and advantages of the invention come up for discussion. Show it:

1 shows a simplified plan view of an X-ray goniometer according to an embodiment of the invention;

FIGS. 2 and 3 are views of parts of the X-ray goniometer according to FIG. 1.

The embodiment shown in a greatly simplified plan view in FIG. 1 of the invention includes a base plate 10 on which a primary beam source 12, a precession goniometer unit 14 with a recording material holder 16 (e.g. a film cassette) and a goniometer head unit 18 are arranged. Primary beam source 12, precession goniometer unit 14 and recording

7524740 29.0176

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material holder 16 can be designed like a commercially available precession goniometer, so a more detailed representation and description are unnecessary.

The goniometer head unit 18 contains a conventional goniometer head 20, to which a glass capillary 22 can be attached, which contains a sample 24 in the form of a crystal and in the primary beam path 26 supports. The goniometer head 20 is attached to a shaft 28 which is mounted in a bearing block 30 and carries a dial 32 with which the angular position of the shaft 28 about its axis ("K-axis") can be adjusted by hand.

According to the invention, the shaft 28 is furthermore via a disengageable worm gear with a worm wheel 34 and a worm 36 coupled to the output shaft of a stepping motor 38. Leaves at two hundred steps per revolution of the motor shaft With an appropriate dimensioning of the worm gear 34-36, a step angle of 0.01 ° of the shaft 28 can be achieved.

The stepper motor 38 attached to its output shaft Screw 36 is mounted pivotably about an axis 40 defined by two shaft stubs and is moved into a position by compression springs 42 pressed, in which the worm 36 is in engagement with the spur gear 34. In this position a e.g. on the motor housing attacking microswitch 44 actuated, the a ^ r « Contains break contact, which is connected to the circuit of the drive device for the precession gear, so that the Precession gear cannot be set in motion as long as shaft 28 is coupled to stepper motor 38.

The worm gear 34-36 can be driven by an eccentric 46, which swivels the motor 38 with the worm wheel 36 about the axis 40, disengaged from ground. When the motor is pivoted, the microswitch 44 is released and the precession unit can start operating be taken.

To prevent unintentional twisting of the goniometer head, this is provided with a locking screw 48, which is assigned a second microswitch 50 with a break contact is, which is in the circuit of the stepper motor "8 and only is closed when the locking screw 48 is loosened. It is therefore not possible to operate the stepper motor 38 with the locking screw tightened 48 must be put into operation so that the stepper motor or the gear unit cannot be damaged.

One or both microswitches can also be used to control a display device, e.g. a lamp, that the set operating mode (precession recording or rotation recording) indicates.

The precession gear is used to perform a rotation recording brought into the zero position, the locking screw 48 is loosened, the gear 34,36 is by corresponding Adjustment of the eccentric 46 by means of an adjusting disk 52 is indented. After inserting and adjusting the sample 24 the primary beam source 12 and the stepping motor 38 can be in operation and the one in the holder Film material are exposed.

In the case of a precession recording, the gear is disengaged by actuating the eccentric 46, which becomes the goniometer shaft 28 fixed in a suitable position by means of the locking screw 48 and the precession recording can then in the usual Way to be carried out.

With the X-ray gonicmeter at hand, a sample can be produced without readjustment and without loss of time a precession recording and a rotation recording can be used, with regard to the sample adjustment completely the same conditions are guaranteed.

7524740 01/29/76

Claims (6)

1) x-ray goniometer with a goniometer head which is used to hold a sample in a primary beam path and is attached to a shaft that can be adjusted about its axis, a recording material holder, a precession gear for pivoting the receptacle holder, and a drive device for the precession gear, characterized in that the shaft ( 28) of the goniometer head (20) is coupled to a drive motor (38) via a disengageable gear (34, 36). 2) X-ray goniometer according to claim 1, characterized in that that the drive motor (38) for the shaft (28) of the goniometer head (20) is a stepping motor. 3) X-ray goniometer according to claim 1 or 2, characterized in that that the gear (34,36) contains a screw (36) connected to the drive motor (38) and which is connected to the drive motor 'Is pivotally mounted in such a way that it is either in or out of engagement with one on the goniometer head shaft (28) attached gear (34) can be brought. 4) X-ray goniometer according to claim 3, characterized by a spring arrangement (42) which engages the worm (36) with the gear (34) strives to press, and a manually operated eccentric arrangement (46,52), the dis worm except Allow engagement with the gear to pivot. 5) X-ray goniometer according to one of the preceding claims, characterized by a Peststellvorrichtung (48) for locking the goniometer head shaft (28) and a locking device (50) which can be actuated by the locking device and which have a Drive of the goniometer head shaft (28) by the drive motor (38) prevents as long as the goniometer head shaft through the 7S24740 29.M.78 I I I I I I i I -6-locking device is locked. ■ 4 6) X-ray goniometer according to one of the preceding claims, characterized in that the motor-gear arrangement (36, 38) is provided with a second locking device (44) is what a commissioning of the drive of the precession gear prevented as long as the gear (34,36) for the goniometer head shaft (28) is engaged.