CN203133617U - Tangent-driving type microsecond-stage high-precision angle adjusting mechanism - Google Patents

Abstract

The utility model provides a tangent-driving type microsecond-stage high-precision angle adjusting mechanism to satisfy microsecond-stage gapless dynamic adjustment to throw angles, roll angles and swing angles of two crystals in a synchrotron-radiation bicrystal monochromator, thereby providing high-quality synchrotron-radiation light required by an experiment. The microsecond-stage high-precision angle adjusting mechanism adopts a flexible hinge to connect an upper plate with a lower plate to form a flexible joint for rotation of the adjusting mechanism. The upper plate, the flexible hinge and the lower plate convert tiny moving of a linear-displacement feeding mechanism to angle tiny deflection of the lower plate. A spring resetting mechanism is adopted to provide resetting deflecting force for the adjusting mechanism. When a linear displacement device moves forward for a certain distance, thrust provided by a linear micro-displacement device, spring pressure and force which enables the flexible hinge to generate deflection form a balance force system, and the flexible hinge drives the lower plate to generate forward deflection. When the linear micro-displacement device moves backward, the spring pressure, the thrust provided by the linear displacement device and the force which enables the flexible hinge to generate deflection form the balance force system, and the flexible hinge drives the lower plate to generate backward deflection.

Description

Tangent drive-type microsecond level high precision angle adjusting mechanism

Technical field

The utility model belongs to the precision optical machinery field, is specifically related to a kind of tangent drive-type angle fine adjustment mechanism.

Background technology

The major function of the microsecond level high precision angle adjusting mechanism that tangent drives is that the two optical flat bodies to the synchrotron radiation double-crystal monochromator carry out the angle fine setting, guarantees that the depth of parallelism of first crystal and second crystal is within the required scope of use.Synchrotron radiation double-crystal monochromator cardinal principle is to utilize Bragg diffraction theorem 2d * sin θ _B=n λ, wherein d is the grating constant of crystal, and n is diffraction progression, and n generally gets 1 in synchrotron radiation, by changing Bragg angle θ _BCan obtain different wavelength X, thereby realize the monochromatization of synchrotron radiation white light.In the actual use of monochromator, first crystal and second crystal depart from ideal position, and the twin crystal malalignment that causes thus causes Bragg angular displacement △ θ _BBecome big, finally cause the diffraction efficiency of crystal to descend.Therefore the position that micro-adjusting mechanism is adjusted crystal need be set, guarantee that incident beam is enough little in the Bragg angle error that twin crystal produces, to obtain higher diffraction efficiency, reach the purpose that improves the monochromator performance.

Crystal fine tuning mechanism is mainly to the throwing angle △ θ of crystal _p, roll angle △ θ _rWith pivot angle △ θ _yRegulate, wherein throw angle △ θ _pRefer to crystal around the small angle deflection of Bragg rotating shaft, mainly play segmentation Bragg corner and improve energy resolution and suppress higher hamonic wave, therefore crystal is arranged the micro-adjusting mechanism of throwing the angular direction, significant to the monochromatization performance of effective raising monochromator; Roll angle △ θ _rRefer to crystal around the small angle deflection of optical axis, can guarantee the parallel of bicrystal and the position of proofreading and correct light beam line downstream hot spot by rolling the angle governor motion, it is significant equally to the stability that improves hot spot that the angle micro-adjusting mechanism is rolled in setting; Pivot angle △ θ _yBe the deflection around the crystal face normal, the pivot angle governor motion is set mainly is the structure cell defective of eliminating crystal etc.

In existing governor motion, regulate by grooving crystal (cutting out a parallel slot at a crystal), use precision bearing system or use deflection platform often, guarantee the desirable parallel position of two crystal.But the grooving crystal is a kind of fixed sturcture, guarantees two crystal parallels by processing, in use can not dynamic adjustments; Use precision bearing system or deflection platform measuring accuracy not high, drive adjustment process and have shortcomings such as backhaul gap.In order to make monochromator that high-quality synchrotron radiation light can be provided, must seek a kind of novel high precision angle adjusting mechanism.

The utility model content

In order to solve the technical matters that exists in the background technology, the utility model provides a kind of tangent drive-type microsecond level high precision angle adjusting mechanism, do not have the gap dynamic adjustments with the microsecond level that satisfies throwing angle to two crystal in the synchrotron radiation double-crystal monochromator, rolls angle and pivot angle, thereby provide experiment required high-quality synchrotron radiation light.

The technical solution of the utility model is as follows:

A kind of tangent drive-type microsecond level high precision angle adjusting mechanism is characterized in that: comprise upper plate, lower plate, flexible hinge, spring reset mechanism, straight-line displacement feed mechanism, power transmission push rod and in order to the straight-line displacement sensor-based system of the current displacement of detection of straight lines micro positioner; Described upper plate and lower plate all have flat part and are offset to the kink of flat part side; The flat part of upper plate is parallel relative with the flat part of lower plate, described flexible hinge is between these two flat parts, the web joint at flexible hinge two ends is fixedlyed connected through two flat parts of screw and this respectively, the kink of upper plate is also parallel relative with the kink of lower plate, and the integral body that forms upper plate and lower plate is harmonious;

Described spring reset mechanism and straight-line displacement feed mechanism all are installed on the kink of lower plate; The kink that the spring born work arbor of spring reset mechanism passes lower plate is fixedlyed connected with the kink of upper plate, is socketed in spring on the spring born work arbor is crimped on the kink of lower plate by gland nut the outside; The power transmission push rod is installed on the kink of upper plate, and hold out against with the output terminal of straight-line displacement feed mechanism, can make the straight-line displacement feed mechanism react on the kink of lower plate through the micrometric displacement of power transmission push rod output, and then the flat part that makes lower plate is that rotary joint produces positive deflection with the flexible hinge, and the pressure of described spring produces the potential energy of the flat part negative sense deflection of lower plate.

Based on above-mentioned basic technical scheme, the utility model is also done following optimization and is limited and improve:

Above-mentioned flexible hinge adopts cosine flexible hinge (otch that namely has cosine shape, two cosine shape otch form flexible rotary joint).

Above-mentioned straight-line displacement feed mechanism comprises straight line micro positioner, spheric nut and screening can, its cathetus micro positioner is integrated with scrambler and gear reducer, the employing DC servo motor drives, and the straight line micro positioner holds out against by spheric nut and power transmission push rod, realizes precision drive; Screening can is used for the shielding synchrotron radiation light to the damage of straight-line displacement device.

Above-mentioned straight-line displacement sensor-based system comprises linear displacement transducer and the sensor-based system push rod that is oppositely arranged, be installed on the kink of upper plate and the kink of lower plate respectively, sensor-based system push rod and the measuring junction of linear displacement transducer contact to measure the displacement of straight-line displacement device.

Be provided with clamping slot at the spring plug of straight-line displacement feed mechanism, power transmission push rod, spring reset mechanism and the fixed position of straight-line displacement sensor-based system push rod; The flat part of upper plate and lower plate is provided with in order to the draw-in groove of flexible hinge to be installed.

The through hole that above-mentioned spring born work arbor passes on the kink of lower plate adopts fixing pin to fixedly connected with the kink of upper plate.

The medial surface both wings of one of them web joint of above-mentioned flexible hinge are provided with semicircular projections (it act as and limit flexible hinge maximum deflection scope in not destroying the flexible hinge performance range).

Between the flat part of the flat part of upper plate and lower plate, also be provided with in order to limit the caging system of range of deflection.

Above-mentioned caging system comprises electric limit switch and mechanical position limitation piece, all is fixed in the flat part of lower plate by screw.The mechanical position limitation piece is used for restriction and breaks through the spacing cosine flexible hinge that damages of electricity because of unexpected accident, electric spacingly is used for limiting the required range of adjustment of engineering equipment.

The utlity model has following technique effect is:

Adopt flexible hinge to connect the flexible joint of upper plate and the rotation of lower plate formation governor motion.The flexible hinge volume is little, do not have characteristics such as machinery friction, no gap, good stability, sensitivity height, improved sensitivity and the precision of angular adjustment.Adopt upper plate, flexible hinge and lower plate that the minute movement of straight-line displacement feed mechanism is converted to the angle small deflection of lower plate, only need select high-precision straight line micro positioner for use, just can realize sufficiently high angular adjustment precision.

Based on structure of the present utility model, can improve the angular adjustment precision by the acting force arm (being the vertical range between straight-line displacement feed mechanism axis and the flexible rotary joint) that lengthens the straight-line displacement feed mechanism, degree of regulation can reach microsecond level even higher.

Adopt spring reset mechanism to provide the deflection force that resets to governor motion, when flexible hinge did not have deflection, thrust and spring pressure that the straight-line displacement device provides balanced each other; When the straight-line displacement device advanced certain distance, the thrust that the straight line micro positioner provides and spring pressure and the power that makes flexible hinge produce deflection formed balanced system of force, and flexible hinge drives lower plate and produces positive deflection; When the straight line micro positioner retreated, the thrust that the pressure of spring and straight-line displacement device provide and the power that makes flexible hinge produce deflection formed balanced system of force, and flexible hinge drives lower plate and produces negative sense deflection.

Adopting the mechanical position limitation piece that the limit range of adjustment of governor motion is carried out machinery limits, the electricity limit switch limits required range of adjustment in using, when emergency makes the anglec of rotation excessive, when breaking through the limit switch limited range, can carry out mechanical position limitation by the mechanical position limitation piece, avoid excessive rotating range to damage cosine flexible hinge, straight line micro positioner and linear displacement transducer.

Adopt linear displacement transducer to feed back current displacement, can reflect the output of current location and angle more intuitively, linear displacement transducer feedback absolute location information, do not need the straight line micro positioner to return zero and seek reference point, certain interval of time returns the zero zero point drift that can be used for the calibration linear displacement transducer.

Description of drawings

Fig. 1 is the synoptic diagram of the governor motion that provides of the utility model.

Fig. 2 is the synoptic diagram at another visual angle of Fig. 1.

Fig. 3 is the structural representation of the flexible hinge of the utility model employing.

The drawing reference numeral explanation:

The 1-upper plate; 2-cosine flexible hinge; 3-straight-line displacement feed mechanism; 4-spring reset mechanism; The 5-lower plate; 6-straight-line displacement sensor-based system; 7-power transmission push rod; The 8-caging system.

Embodiment

Be example with the cosine flexible hinge, specifically set forth technical solutions of the utility model.

At first, the cosine flexible hinge is the flexible hinge with cosine function shaped cutout, can access the relation between the angle offset and power and displacement accurately, calculates deflection angle θ in the use by theory _y, θ _xAnd θ _zAccurate expression formula be:

${\mathrm{\&theta;}}_y=\frac{96a{M}_y}{\mathrm{\&pi;Eh}}\&CenterDot;[\frac{2c(c+t)(3c+t)}{{(2c+t)}^2{(4\mathrm{ct}+t^2)}^2}+\frac{(6{\mathrm{<figure-callout\; id="2"\; label="c"\; filenames="20132007021281000032.png,DEST\_PATH\_HDA00003325737400011.png"\; state="\{\{state\}\}">c</figure-callout>}}^2+4\mathrm{ct}+t^2)\arctan \left(\sqrt{\frac{4c+t}{t}}\right)}{{(4\mathrm{ct}+t^2)}^{\frac{5}{2}}}]$

${\mathrm{\&theta;}}_x=\frac{96a{M}_x}{\mathrm{\&pi;}{\mathrm{<figure-callout\; id="3"\; label="Gh"\; filenames="20132007021281000032.png,DEST\_PATH\_HDA00003325737400011.png"\; state="\{\{state\}\}">Gh</figure-callout>}}^3}\&CenterDot;\frac{\arctan \left(\sqrt{\frac{4c+t}{t}}\right)}{\sqrt{4\mathrm{ct}+{\mathrm{<figure-callout\; id="2"\; label="t"\; filenames="20132007021281000032.png,DEST\_PATH\_HDA00003325737400011.png"\; state="\{\{state\}\}">t</figure-callout>}}^2}}$

${\mathrm{\&theta;}}_z=\frac{96a{M}_z}{\mathrm{\&pi;}{\mathrm{Eh}}^3}\&CenterDot;\frac{\arctan \left(\sqrt{\frac{4c+t}{t}}\right)}{\sqrt{4\mathrm{ct}+{\mathrm{<figure-callout\; id="2"\; label="t"\; filenames="20132007021281000032.png,DEST\_PATH\_HDA00003325737400011.png"\; state="\{\{state\}\}">t</figure-callout>}}^2}}$

Wherein, M _y, M _xAnd M _zBe respectively the deflecting torque around Y, X and Z axle, t is the flexible joint segment thickness, and c is the cosine notch depth, and a is half of kerf width, and h is the thickness of flexible hinge, and E is the elastic modulus of material, and G is the material modulus of shearing.

The greatest flexibility deformation angle θ of flexible hinge _YmaxAccurate expression formula be:

${\mathrm{\&theta;}}_{y\max }=\frac{16a{\mathrm{<figure-callout\; id="2"\; label="t"\; filenames="20132007021281000032.png,DEST\_PATH\_HDA00003325737400011.png"\; state="\{\{state\}\}">t</figure-callout>}}^2{\mathrm{\&sigma;}}_{\max }}{\mathrm{\&pi;E}}\&CenterDot;[\frac{2c(c+t)(3c+t)}{{(2c+t)}^2{(4\mathrm{ct}+t^2)}^2}+\frac{(6{\mathrm{<figure-callout\; id="2"\; label="c"\; filenames="20132007021281000032.png,DEST\_PATH\_HDA00003325737400011.png"\; state="\{\{state\}\}">c</figure-callout>}}^2+4\mathrm{ct}+t^2)\arctan \left(\sqrt{\frac{4c+t}{t}}\right)}{{(4\mathrm{ct}+t^2)}^{\frac{5}{2}}}]$

Wherein, σ _MaxBe the flexible hinge YIELD STRENGTH, other variable symbols together above.

Thus, adopt the cosine flexible hinge can accurately calculate its angular deflection amount, eliminated oval flexible hinge, circular arc flexible hinge and other cut forms flexible hinges because can not obtaining the analytical error that accurate angular deflection expression formula is brought, and the cosine flexible hinge has more succinct angular deflection expression formula.Analyze through the ANSYS finite element simulation, under the suitable situation of notch parameters: the largest deformation angle of cosine flexible hinge is 1.56 times of circular arc flexible hinge approximately, therefore has bigger largest deformation angle; And the linear deformation amount of circular arc flexible hinge when stressed is 1.56 times of cosine flexible hinge that are subjected to identical power approximately, thereby cosine flexible hinge ratio of rigidity circular arc flexible hinge is big, thereby the cosine-shaped flexible hinge has higher stability, and is more obvious to the stability that improves the synchrotron radiation hot spot.

Figure 1 shows that the tangent drive-type microsecond level high precision angle adjusting mechanism based on the cosine flexible hinge of present embodiment.This governor motion is that the monochromator crystal is carried out the angle fine adjustment, for making the crystal throw angle regulated, rolling the angle and pivot angle can reach the required requirement of engineering equipment, governor motion need have higher degree of regulation and enough stability, in the process that governor motion is regulated, can not have the backlash gap in addition, otherwise the crystal position after regulating changes because of extraneous interference easily.Therefore, the utility model adopts the straight-line displacement feed mechanism, small linear displacement amount is changed angled amount of deflection, the precision of straight-line displacement feed mechanism can determine final angular adjustment precision, and adopted high precision and do not had the flexible joint that turns round the gap, make governor motion have enough stability.

Consider that this governor motion is applicable to vacuum equipment, and to the high standard requirement of degree of regulation and stability, the utility model design point of view micro-adjusting mechanism comprises upper plate (1), lower plate (5), cosine flexible hinge (2), power transmission push rod (7), spring reset mechanism (4), straight-line displacement feed mechanism (3), straight-line displacement sensor-based system (6) and caging system (8).

The stationkeeping of upper plate (such as, can be fixed on the crystal cartridge of monochromator; In addition, when a plurality of the utility model governor motion series connection of needs are used, upper plate as the series connection link also can be connected with the lower plate of other adjustment structures), upper plate and lower plate provide cradle head by the cosine flexible hinge, realize that no gap do not have the high precision that rubs and rotate.The straight-line displacement feed mechanism is installed on the lower plate, and the power transmission push rod is fixed in upper plate, and straight-line displacement feed mechanism output terminal and power transmission push rod hold out against, and when straight-line displacement output feeding, straight-line displacement device and lower plate are to positive dirction deflection; Spring reset mechanism comprises gland nut, spring born work arbor, fixing pin and spring totally four parts, the through hole that spring born work arbor passes on the lower plate links to each other with upper plate with pin, one end of spring born work arbor connects spring, spring is pressed on the lower plate, compress and can regulate the pressure that gland nut comes regulating spring with gland nut, the pressure of spring will make lower plate be inconjunction with flexible hinge together to negative direction deflection, and its deflection is carried out balance by the straight-line displacement device.If the micrometric displacement that the straight line micro positioner is walked out is that straight line micro positioner axis is that L(is acting force arm to the vertical range of flexible hinge flexible joint), then the pass of straight line micrometric displacement Δ S and corner Δ α is:

From formula as can be seen, adopt the straight-line displacement device of small straight line micrometric displacement and the degree of regulation that the increase acting force arm all can improve governor motion.

Straight-line displacement device sensing system comprises sensor-based system push rod and linear displacement transducer two parts, the sensor-based system push rod is fixed on upper plate, linear displacement transducer is fixed on lower plate, measuring junction and the push rod of linear displacement transducer hold out against, linear displacement transducer feeds back current displacement, can reflect the output of current location and angle more intuitively.Linear displacement transducer can feed back absolute location information usually, does not so just need micro positioner to return zero and seeks reference point, and certain interval of time returns the zero zero point drift that can be used for the calibration linear displacement transducer.The mechanical position limitation of caging system and the spacing lower plate that is fixed on of electricity along with lower plate is carried out positive and negative deflection together, are carried out spacing to positive dirction and negative direction deflection that governor motion is regulated.

The principle of work of the utility model in the angular adjustment system is: computer control straight line micro positioner output straight-line feed, linear displacement transducer detection of straight lines Displacement Feedback is given computing machine.The straight-line displacement device provides deflection force by the power transmission push rod to governor motion, makes the lower plate drive crystal mount pad (on the crystal mount pad diffraction crystal being housed) of governor motion carry out positive deflection.When returning as need, computer control straight line micro positioner retreats, and the spring pressure of spring reset mechanism makes the governor motion lower plate to negative direction deflection, resets.Can make things convenient for regulating and controlling mechanism to find the angle that makes the monochromator best performance by computing machine, make two diffraction crystals throw the angle and roll the angular direction and reach parallel, satisfy the engineering equipment demand.

Claims (9)

1. tangent drive-type microsecond level high precision angle adjusting mechanism is characterized in that: comprise upper plate (1), lower plate (5), flexible hinge, spring reset mechanism (4), straight-line displacement feed mechanism (3), power transmission push rod (7) and in order to the straight-line displacement sensor-based system (6) of the current displacement of detection of straight lines micro positioner; Described upper plate (1) and lower plate (5) all have flat part and are offset to the kink of flat part side; The flat part of upper plate (1) is parallel relative with the flat part of lower plate (5), described flexible hinge is between these two flat parts, the web joint at flexible hinge two ends is fixedlyed connected through two flat parts of screw and this respectively, the kink of upper plate (1) is also parallel relative with the kink of lower plate (5), and the integral body that forms upper plate (1) and lower plate (5) is harmonious;

Described spring reset mechanism (4) and straight-line displacement feed mechanism (3) all are installed on the kink of lower plate (5); The kink that the spring born work arbor of spring reset mechanism (4) passes lower plate (5) is fixedlyed connected with the kink of upper plate (1), is socketed in spring on the spring born work arbor is crimped on the kink of lower plate (5) by gland nut the outside; Power transmission push rod (7) is installed on the kink of upper plate (1), and hold out against with the output terminal of straight-line displacement feed mechanism (3), can make straight-line displacement feed mechanism (3) react on the kink of lower plate through the micrometric displacement of power transmission push rod (7) output, and then the flat part that makes lower plate (5) is that rotary joint produces positive deflection with the flexible hinge, and the pressure of described spring produces the potential energy of the flat part negative sense deflection of lower plate (5).

2. tangent drive-type microsecond level high precision angle adjusting mechanism according to claim 1 is characterized in that: described flexible hinge employing cosine flexible hinge.

3. tangent drive-type microsecond level high precision angle adjusting mechanism according to claim 1 and 2, it is characterized in that: described straight-line displacement feed mechanism (3) comprises straight line micro positioner, spheric nut and screening can, its cathetus micro positioner is integrated with scrambler and gear reducer, the employing DC servo motor drives, the straight line micro positioner holds out against by spheric nut and power transmission push rod, realizes precision drive; Screening can is used for the shielding synchrotron radiation light to the damage of straight-line displacement device.

4. tangent drive-type microsecond level high precision angle adjusting mechanism according to claim 1 and 2, it is characterized in that: described straight-line displacement sensor-based system (6) comprises linear displacement transducer and the sensor-based system push rod that is oppositely arranged, be installed on the kink of upper plate (1) and the kink of lower plate (5) respectively, the sensor-based system push rod contacts with the measuring junction of linear displacement transducer, to measure the displacement of straight-line displacement device.

5. tangent drive-type microsecond level high precision angle adjusting mechanism according to claim 1 and 2 is characterized in that: be provided with clamping slot at the spring plug of straight-line displacement feed mechanism (3), power transmission push rod, spring reset mechanism and the fixed position of straight-line displacement sensor-based system push rod; The flat part of upper plate (1) and lower plate (5) is provided with in order to the draw-in groove of flexible hinge to be installed.

6. tangent drive-type microsecond level high precision angle adjusting mechanism according to claim 1 and 2 is characterized in that: the through hole that described spring born work arbor passes on the kink of lower plate (5) adopts fixing pin to fixedly connected with the kink of upper plate (1).

7. tangent drive-type microsecond level high precision angle adjusting mechanism according to claim 1 and 2, it is characterized in that: the medial surface both wings of one of them web joint of flexible hinge are provided with semicircular projections.

8. tangent drive-type microsecond level high precision angle adjusting mechanism according to claim 1 and 2 is characterized in that: also be provided with in order to limit the caging system of range of deflection between the flat part of the flat part of upper plate and lower plate.

9. tangent drive-type microsecond level high precision angle adjusting mechanism according to claim 8, it is characterized in that: described caging system comprises electric limit switch and mechanical position limitation piece, all is fixed in the flat part of lower plate by screw.

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