SS SS RR CC

O. Evdokov, B. Pirogov, B. Tolochko, I. Zhogin

Institute of Solid State Chemistry and Mechanochemistry

N. Gavrilov, A. Kosov, M. Sheromov, V. Tsukanov

Budker Institute of Nuclear Physics

A. Shmakov

Boreskov Institute of Catalysis

Compact Wave Strain-Friction Compact Wave Strain-Friction

reducers (0.3"–1.5" mini-reducers (0.3"–1.5" mini-

goniometers) for X-ray optics goniometers) for X-ray optics

at Siberian SR Centerat Siberian SR Center

OutlineOutline

• Introduction: the problem of precision rotation feedthrough into high vacuum and basics of Wave Strain-Friction (WSF) drive

• Design: WSF-reducers in drawings and in reality -- vacuum (CF63) and non-vacuum versions

• Parameters: testing WSF-reducers with encoder LIR-1170A (accuracy of 0.1 mdeg, or 0.36 arc sec)

• Applications: (1) single-crystal high-vacuum drum-type monochromator (where fast change of crystals is possible); (2) double-crystal high-vacuum fixed-exit monochromator

• Conclusion and Acknowledgments

IntroductionIntroduction• Feedthrough of precision motion (rotation) into high vacuum

is a difficult problem (high vacuum mechanics is expensive)

a) viton sealing and differential pumpingb) piezoceramicsc) strain & friction mechanics – most simple

way (N Gavrilov)

• ABC of Wave Strain-Friction (WSF) drive

Outer rigid ring

Inner flexible ring

Wave generator

Elasticdeformations,

D – inner diameter of outer ringd – outer diameter of inner ringk – coefficient of reduction – elastic deformations

k

k0

DesignDesign WSF-reducers in drawings: vacuum (CF63)

and non-vacuum versions

stepperstepper

… and in reality

Parameters

Parameters

Testing WSF-reducers with encoder LIR-1170A

encoder

stepper0.9° (0.45°)

period ~ 650 h-stepsh-step ~ 0.32”±0.35”

period ~ 800/3 h-steps

period ~650 stepsstep ~ 0.33”

vacuum variant

Applications

Applications Single-crystal high-vacuum drum-type monochromator (design: E.I. Pokhlebenin )

Ion chamber

Monochromator

2 = 30°

Si 111 – 7.64 keV

Si 220 – 12.47 keV

Single-crystal high-vacuum drum-type monochromator installed on 6-th beam-line

Ion chamber Monochromator

Applications

Applications Double-crystal high-vacuum fixed-exit monochromator(design: N.G. Gavrilov, I.L. Zhogin)

C1 - the first crystal; C2 - the second crystal (Si 111 or 311)

3 - horizontal (Huber) stage (working range of ~190 mm)

4 - bellows; 5 - plunger-rod (with tubes for water cooling of the first crystal); beam offset is h=40 mm; range of energy (Si111) 5–19 keV;

L1, L2 - levers clamping to their rollers R1 and R2; Li-lever rotates Ci-crystal

SRI-03 proc., p. 691

Laser

Ruler &webcam

(~10m path to ruler)

Optical testing kinematics of monochromator in vacuum

Kinematical part of the double-crystal high-vacuum monochromator (optical testing in air)

WSF-

redu

cer

Beam testing DC-monochromator

Ionchamber

Fine (de)tuning of the first crystal

10 20 300

2

4

6

8

(V1+

V2)/

I VE

PP

time, s (x 50 steps/s)-15 -10 -5 0 5 10 150

1

2

3

4

5Correlation of 2 rock.curves (autocorrelation)

, arc.sec.

E=11 keV, Si111”

Correlation of two rock.curves(autocorrelation; XOP)

1 h-step ~ 0.03”

(DShI-200

200 steps/rot.)

time, s (x 50 half-step/s)

Plan viewPlan view

0“Explo-sion”

(bunker VEPP-3)

Mono1

New ‘top’

station

Mono2

?

ConclusionConclusion

• WSF-reducers are a good choice (compact and inexpensive) for a feedthrough of precision rotary motion into high vacuum (or other environment)

• their performance can be improved by increasing the diameters of rings (and with better manufacturing)

• to be continued later

AcknowledgementsAcknowledgements

• Grants: Russian Foundation for Basic Research (N Gavrilov)

Bortnik Foundation (A Shmakov, B Tolochko)

• SSRC Users and staff: Thanks for tolerance and assistance

• Audience: Thank you for your attention