阅读说明：本技术 一种光学望远镜的反射镜切换机构 (Reflector switching mechanism of optical telescope ) 是由 顾伯忠 何鑫 姜翔 乐中宇 张志永 于 2021-09-08 设计创作，主要内容包括：本发明一种光学望远镜的反射镜切换机构涉及机械设计制造技术领域。天文学是一门以观测为主的学科,天文光学望远镜是主要手段之一。望远镜上目前常用的光学系统主要是两镜系统,以卡塞格林式或R-C式为主,其中往往在两镜中间增加一面平面反射镜,以增加反射焦点。在使用各个焦点时,需要对这块平面镜进行位置的移动。其中在卡焦工作状态时,需要将反射镜装配体移出成像光路之外,避开卡焦光路通道；在耐焦或是折转卡焦工作状态时,便需要将反射镜运动到与光轴成45度的位置,将副镜反射的光线折转到成像焦面上。本专利设计出一种全新的用于望远镜的反射镜切换机构,可以简单的实现反射镜的位置运动。运动可靠性高,定位精度准确。(The invention discloses a reflector switching mechanism of an optical telescope, and relates to the technical field of mechanical design and manufacture. Astronomy is a subject mainly for observation, and an astronomical optical telescope is one of the main means. The optical system commonly used in the telescope at present is mainly a two-mirror system, mainly of the Cassegrain type or the R-C type, wherein a plane reflector is often added between the two mirrors to increase the reflection focus. When using each focal point, the mirror needs to be moved in position. When the lens is in a focusing working state, the reflector assembly body needs to be moved out of an imaging light path to avoid a focusing light path channel; when the optical imaging device is in a focus-resistant or focus-folding working state, the reflector needs to be moved to a position which forms an angle of 45 degrees with the optical axis, and light reflected by the secondary mirror is folded to an imaging focal plane. This patent designs a brand-new speculum switching mechanism for telescope, the position motion of realization speculum that can be simple. The motion reliability is high, and the positioning accuracy is accurate.)

1. A mirror switching mechanism for an optical telescope, comprising: the device comprises a reflector supporting structure, an overturning switching mechanism, a translation switching mechanism and a rotary switching assembly body.

2. The mirror switching mechanism of an optical telescope according to claim 1, wherein the mirror support structure is composed of a mirror (1), side support bulbs (2), support rods (3), connecting pieces (4), invar pads (5), a support mirror chamber (6) and a connecting shaft (7);

the main body of the support mirror chamber (6) is of an octagonal structure, has a certain thickness and is provided with a bottom surface, a round hole is arranged at the center position inside the bottom surface, a triangle formed by the three connecting pieces (4) surrounds the outer side of the round hole, and a circular groove is arranged at the center of the triangle and used for mounting a side support ball head (2); three supporting rods (3) are respectively arranged on three vertex angles of the triangle; the middle part of the support rod (3) connected with the connecting piece (4) is provided with a deep groove ball bearing; invar steel pads (5) are arranged at the two ends of each supporting rod (3); the reflector (1) is arranged in the supporting mirror chamber (6) and is contacted with the side supporting ball heads (2) and the invar pad (5); the connecting shafts (7) are arranged on the back surface of the supporting mirror chamber (6), are positioned in the middle and the lower part of the back surface, and are symmetrically provided with two groups of 4 connecting shafts (7).

3. The mirror switching mechanism of claim 1, wherein the flip switching mechanism comprises: the device comprises a mounting plate (8), a supporting bracket (9), a grating ruler (10), a reading head (11), a lead screw fixing seat A (12), a lead screw nut (13), a lead screw (14), a reflector assembly body (15), a lead screw fixing seat B (16), a worm wheel (17), a worm (18), a worm fixing seat A (19), a coupling (20), a driving motor (21), a worm fixing seat B (22), a guide rail A (23), a slide block A (24), a guide rail B (25), a slide block B (26), a rotating frame B (27) and a rotating frame A (28);

a circular through hole is formed in the middle of the mounting plate (8), three sides of the supporting bracket (9) are arranged on the mounting plate (8) in a surrounding mode, mounting main parts on the parallel supporting brackets on two sides are identical, and a grating ruler (10) and a reading head (11) are additionally arranged on the parallel supporting bracket on one side; a driving motor (21) is arranged on the back plate supporting bracket on one side; the method comprises the following specific steps:

the guide rails A (23) are symmetrically arranged on the support brackets (9) which are parallel to the two sides, the screw rod (14) is arranged on the guide rails A (23), the two ends of the screw rod (14) are respectively fixed with the screw rod (14) through the screw rod fixing seat A (12) and the screw rod fixing seat B (16), and the mode that one end of the screw rod is fixed and the other end of the screw rod is floating is adopted; the screw rod nut (13) is directly connected with the rotating frame A (28), and the floating end of the screw rod (14) is provided with a worm wheel (17);

a driving motor (21) is arranged on the back plate supporting bracket on one side, is a special motor, adopts a double-output head mode, namely, connecting shafts are arranged at two ends of the driving motor (21) and two worms (18) are connected together through two couplers (20); a worm (18) matched with the worm wheel (17) is fixedly arranged on the worm fixing seat A (19) and the worm fixing seat B (22) at the same time;

triangular supports are parallelly arranged on two sides of the circular through hole of the mounting plate (8) and used for supporting a guide rail B (25), and a sliding block B (26) is arranged on the guide rail B (25); the sliding block B (26) is connected with the rotating frame B (27), the sliding block B (24) is connected with the rotating frame A (28), and the rotating frame A (28) and the rotating frame B (27) are respectively arranged on the connecting shaft (7) at the middle part and the lower part of the back surface of the mirror supporting chamber (6) of the mirror assembly body, so that the mirror supporting structure and the turnover switching mechanism are connected together through the connection; the worm wheel (17) is directly assembled on the screw rod (14), the driving motor (21) drives the worm (18) to rotate, the worm wheel (17) meshed with the worm wheel drives the screw rod (14) to rotate, so that the screw rod nut (13) horizontally moves, and the rotating frame A (28) is driven to move; the guide rail B (25) and the guide rail A (23) have a specific calculated angle, and the moving process of the lead screw nut (13) simultaneously drives the rotating frame A (28), the rotating frame B (27), the connected slide block A (24) and the slide block B (26) to perform translational motion on the slide block guide rail, so that the angle is turned;

grating chi (10) are installed on the fixing base of slider guide rail, and reading head (11) are installed on slider A (24).

4. The mirror switching mechanism of claim 1, wherein the translation switching mechanism comprises: the mounting and fixing device comprises a mounting and fixing plate (29), a translation guide rail C (30), a translation sliding block C (31), a translation worm fixing seat B (32), a translation worm (33), a translation worm wheel (34), a coupler (35), a driving motor (36), a translation guide rail frame (37), a translation guide rail D (38), a translation sliding block D (39), an inclined connecting block (40), a translation lead screw (41), a translation guide rail E (42) and a lead screw fixing seat (43);

the overturning switching mechanism is arranged on a sliding block (31), and a pair of translation guide rails C (30) is arranged on the mounting fixing plate (29) in parallel; the turnover switching mechanism can move on a translation guide rail C (30) of the installation fixing plate (29);

a translation worm fixing seat B (32) is fixed on the back plate supporting bracket on one side; the driving motor (36) is arranged on the translation worm fixing seat B (32); meanwhile, one end of a translation lead screw (41) is also fixedly arranged on a translation worm fixing seat B (32), and the other end of the translation lead screw is fixed by a lead screw fixing seat (43); the translation worm wheel (34) is fixedly arranged at one end of the translation lead screw (41); the driving motor (36) is connected with the translation worm (33) through a coupler (35); the translation guide rail bracket (37) is fixed on the mounting fixing plate (29) and does not move together with the turnover switching mechanism; a translation guide rail D (38) is arranged on a translation guide rail bracket (37), and a translation guide rail E (42) is arranged on a back plate supporting bracket on one side; the two translation sliding blocks D (39) clamp the inclined connecting block (40) in the middle and are fixedly connected into a whole, the inclined connecting block (40) is connected with a nut of the translation lead screw (41), and the inclined connecting block (40) moves along the translation lead screw (41) and drives the two translation sliding blocks D (39) to simultaneously slide along the translation guide rail D (38) and the translation guide rail E (42); the translation guide rail bracket (37) and the inclined connecting block (40) both have a certain angle relative to the turnover switching mechanism;

the driving motor (36) works to drive the translation worm (33) to be meshed with the translation worm wheel (34) to rotate, so that the translation lead screw (41) is driven to rotate, and the nut of the translation lead screw is connected with the inclined connecting block (40), so that the rotation motion is changed into linear motion along with the follow-up; because the inclined rotating block (40) and the translation guide rail bracket (37) have certain angles, the horizontal movement is acted by tangential component force, and the translation movement vertical to the screw shaft is realized.

5. The mirror switching mechanism of claim 1, wherein the rotary switching assembly comprises: the device comprises a supporting box body (44), a coded disc reading head (45), a coded disc (46), a coded disc mounting bracket (47), a direct-drive motor rotor mounting bracket (48), a stator mounting bracket (49), a direct-drive motor stator assembly (50), a direct-drive motor rotor assembly (51), a large round nut (52), a rotating shaft (53), an angular contact ball bearing A (54) and an angular contact ball bearing B (55);

an angular ball bearing A (54) and an angular ball bearing B (55) are installed face to face and used for supporting a rotating shaft (53); a rotor assembly (51) and a stator assembly (50) of the direct drive motor are respectively assembled on the rotating shaft (53) and the supporting box body (44) through corresponding mounting brackets, namely a rotor mounting bracket (48) and a stator mounting bracket (49) of the direct drive motor; the coded disc (46) is assembled on the rotating shaft (53) through a screw and a coded disc mounting bracket (47), and a reading head (45) of the coded disc is mounted on the supporting box body (44);

the direct drive motor works to drive the whole rotating shaft (53) to rotate, and the reading head (45) can detect the rotating angle of the coded disc (46) so as to detect and feed back the position; the translation switching mechanism and the turnover switching mechanism are arranged on the rotating shaft (53) and can realize integral rotation; the rotating shaft (53) is a hollow shaft, and a reflected light path from the secondary mirror can pass through the rotating shaft.

6. The mirror switching mechanism of an optical telescope according to claim 2, wherein the side support bulbs (2) are made of invar.

Technical Field

The invention belongs to the technical field of mechanical design and manufacture, and particularly relates to position switching and adjustment of a plane reflector in an astronomical optical telescope.

Background

Astronomy has developed and broken through highly telescope-dependent observations, of which optical telescopes are one of the important observation means. In the astronomical optical telescope, because the limitation of the refraction type telescope is not suitable for the design with larger caliber, the present large caliber optical telescope is a reflection type, generally is a two-mirror system, the optical system mainly adopts Cassegrain type and R-C type, wherein a plane reflector is often added between the two mirrors to increase the focus, more imaging focuses can be arranged with more imaging instruments, for rare astronomical observation, the precious observation time of the telescope is utilized, and the great significance is provided for scientific output. The mirror acting as a turning focus needs to be moved in position to switch between different focuses. When the focal point is clamped in a working state, the reflector assembly body needs to be moved out of the imaging light path, and a focal point clamping light path channel is avoided; when the focus is resistant or the folding axis focus works, the reflecting mirror needs to be moved to a position forming an angle of 45 degrees with the optical axis, and the light path from the secondary mirror is reflected to the focus resistant or folding axis focus resistant imaging focal plane. Therefore, for the purpose of realizing the optical path, the mirror switching mechanism needs to perform angle switching between 45 degrees and 90 degrees and translational motion so as to realize the purpose of avoiding the focal channel.

Disclosure of Invention

The invention provides a plane reflector switching mechanism for an astronomical optical telescope, which realizes angle switching and focus switching of a three-mirror system, enables terminal instruments installed on different platforms to be fully utilized and improves observation efficiency. The invention has the advantages of simple switching mechanism, few moving mechanisms, high position precision and no additional mirror surface additional force, and can well meet the requirements in engineering.

The invention achieves the above purpose through the following technical scheme: a reflector switching device of an optical telescope is arranged on a primary mirror chamber of a large and medium-sized optical telescope, is coaxially arranged with a lens barrel, is positioned between a primary mirror and a secondary mirror, and is an important component three-mirror for realizing focus switching. The device is characterized by consisting of three-dimensional motion and comprising a turnover mechanism for switching between parallelism of three mirror optical axes and 45 degrees; a translation mechanism for making the reflector coaxial with the optical axis; and the rotating mechanism is used for angle adjustment or focus switching during installation.

Under the trend that the aperture of the telescope is increasingly larger, in order to improve the observation efficiency of the telescope, the focus of the telescope needs to be fully utilized, so that the three lenses serving as key elements for turning the focus are more important. Because of cost, technology, imaging effect and the like, the refraction type telescope is not used in a large-aperture telescope any more, and the existing telescope mainly takes a reflection type telescope as a main part. The light of the astrology in the universe passes through space-time of hundreds of millions of light years, comes to the primary mirror of the telescope, then reaches the secondary mirror through the reflection of the primary mirror, and the secondary reflection passes through the middle hole of the primary mirror, and the imaging of the star image and various spectral information can be obtained through the processing of an optical terminal instrument. A turning reflector is added between the primary and secondary mirrors to reflect the light path of the secondary mirror to another focus for three times. The switching of three mirrors can make the telescope body install a plurality of terminal instrument, make full use of valuable observation time, realize that observation efficiency maximize.

A mirror switching mechanism for an optical telescope comprising: the device comprises a reflector supporting structure, an overturning switching mechanism, a translation switching mechanism and a rotary switching assembly body.

The reflector supporting structure comprises a plane reflector, three connecting pieces, a supporting rod support, a central side supporting ball head shaft, a supporting mirror chamber, a supporting shaft and other parts.

The plane reflector is made of low-expansion glass ceramics which has little influence on the change of temperature; the bottom support and the side support are made of invar steel which is in direct contact with the mirror surface, the expansion coefficient of the bottom support and the side support is small along with the temperature change, the bottom support and the side support are not sensitive to the temperature like other alloys, and the difference caused by expansion with heat and contraction with cold of a metal material due to the temperature can be reduced to a great extent, so that the influence of the support on the mirror surface shape is caused. Three groups of follow-up bottom supports and side supports are connected to the mirror chamber, and four connecting shafts are connected to the mirror chamber.

The turnover switching mechanism mainly comprises a mounting plate, a turnover support, two sets of worm and gear assemblies, two sets of ball screw assemblies, a driving motor with double output shafts, a coupler, a worm fixing support, two sets of identical first sliding block guide rail assemblies, two sets of identical second sliding block guide rail assemblies, a high-precision position grating ruler, a reflector supporting assembly body and other parts.

The mounting plate of the turnover switching mechanism mainly has the functions of installation and support, is used for middle transition, can be provided with a turnover support, and is directly connected with a rotary assembly body through a screw. The lead screw shaft is assembled on two sides through the fixed seat, and the turning action is realized. The extension length of the screw shaft is directly connected with the turbine and can be realized through the tensioning sleeve. The nut that the lead screw matches is connected on the revolving rack, and the middle can be equipped with the bearing. The motors with double output shafts are respectively connected with the worms on two sides through the shaft couplings, and the worms are fixedly assembled on the worm fixing supports. Two groups of identical first guide rail sliding blocks are respectively arranged on two sides of the plane mirror assembly body and are parallel to the screw rod, wherein the guide rails are arranged on the overturning bracket, and the rotating bracket is arranged on the sliding blocks; two groups of identical second guide rail sliding blocks are also arranged on the overturning bracket and are arranged in parallel, and a calculated angle is formed between the two groups of identical second guide rail sliding blocks and the first group of guide rails; the short rotating frame is arranged on the second group of sliding blocks. The grating ruler is arranged on one side of the plane mirror assembly body and is fixed, the reading head of the grating ruler follows up with the movement of the reflector assembly body, and the reading head is used for position detection, feeding back to the motor and controlling the realization of the movement.

The ball screw pair is in a high-precision grinding grade and applies pre-tightening, and the allowable rotating static torque of the ball spline pair is larger than the friction torque generated by the thread pair and the end face friction pair; the ball linear guide rail also adopts high-precision grade, applies pre-tightening, has higher operation precision and better rigidity.

The translation switching mechanism mainly comprises guide rail sliding blocks, a worm and gear assembly, a driving motor, a ball screw, a mounting and fixing support and the like.

The turning switching device is arranged on two guide rail sliding blocks which are arranged in parallel, the driving motor is directly connected with the worm through the coupler, the worm wheel is connected on the screw shaft and is positioned at a 90-degree staggered position with the worm, and two ends of the screw are fixed through the mounting seat; a nut matched with the screw rod is connected to the moving block, the moving block is simultaneously connected to the two guide rail sliding blocks, and one group of guide rail sliding blocks are arranged on the turnover mechanism assembly body and move simultaneously with the whole assembly body; the other group of guide rail sliding blocks are arranged on the bottom mounting plate, the guide rails are fixed in position, do not follow up and have a certain angle, and the whole assembly body is driven to move through tangential component force brought by the inclined plane.

The rotary switching device comprises a rotating shaft, a supporting bearing, a direct drive motor, a supporting box body, a position code disc and other parts.

The high-precision code disc is arranged on the rotating shaft, coaxially arranged and rotated together, and a reading head of the high-precision code disc is arranged on the supporting box body and used for measuring the rotating angle position and feeding back and controlling the motion of the motor; the silicon steel sheet and the magnetic steel component of the motor rotor are stuck on the rotating shaft; the winding part assembly is fixedly arranged on the supporting box body.

Drawings

The invention will be further explained with reference to the drawings.

FIG. 1 is a schematic diagram of a mirror support structure;

FIG. 2 is a schematic view of an observation position of the angle switching mechanism;

FIG. 3 is a schematic diagram of the path of the angle switching mechanism;

FIG. 4 is a schematic diagram of the translation switching mechanism;

FIG. 5 is a schematic view of a flipping, translating and switching mechanism;

FIG. 6 is a perspective view A of the flipping and translating switching mechanism;

FIG. 7 is a perspective view B of the flipping and translating switching mechanism;

fig. 8 is a perspective view of the flipping, translating and switching mechanism C;

FIG. 9 is a schematic view of a rotary switching assembly in its entirety;

fig. 10 is an exploded view of the rotary switching assembly.

1. The reflecting mirror comprises a reflecting mirror body, 2 side supporting ball heads, 3 supporting rods, 4 connecting pieces, 5 invar steel pads, 6 supporting mirror chambers and 7 connecting shafts;

8. the automatic reading device comprises a mounting plate, 9 supporting brackets, 10 grating rulers, 11 reading heads, 12 lead screw fixing seats A, 13 lead screw nuts, 14 lead screws, 15 reflector assemblies, 16 lead screw fixing seats B, 17 worm gears, 18 worms, 19 worm fixing seats A, 20 couplers, 21 driving motors, 22 worm fixing seats B, 23 guide rails A, 24 slide blocks A, 25 guide rails B, 26 slide blocks B, 27 rotating frames B, 28 rotating frames A;

29. the method comprises the following steps of mounting a fixed plate, 30, translation guide rails C, 31, translation sliding blocks C, 32, translation worm fixing seats B, 33, translation worms, 34, translation worm wheels, 35, a coupler, 36, a driving motor, 37, a translation guide rail frame, 38, translation guide rails D, 39, translation sliding blocks D, 40, an inclined connecting block, 41, a translation lead screw, 42, translation guide rails E, 43 and a lead screw fixing seat;

44. the direct-drive motor rotor assembly structure comprises a support box body, 45 coded disc reading heads, 46 coded discs, 47 coded disc mounting brackets, 48 direct-drive motor rotor mounting brackets, 49 stator mounting brackets, 50 direct-drive motor stator assemblies, 51 direct-drive motor rotor assemblies, 52 large round nuts, 53 rotating shafts, 54 angular contact ball bearings A and 55 angular contact ball bearings B.

Detailed Description

The device of the invention comprises: the mirror assembly body comprises a mirror supporting structure (namely a mirror assembly body), an overturning switching mechanism (namely an overturning assembly body), a translation switching mechanism (namely a translation assembly body) and a rotation switching assembly body.

The reflector supporting structure is shown in a schematic diagram of fig. 1 and comprises a reflector 1, a side supporting ball 2, a supporting rod 3, a connecting piece 4, an invar steel pad 5, a supporting mirror chamber 6, a connecting shaft 7 and other main parts.

The main body of the support mirror chamber 6 is of an octagonal structure, has a certain thickness and is provided with a bottom surface, a round hole is arranged at the center position inside the bottom surface, a triangle formed by the three connecting pieces 4 is enclosed outside the round hole, and a circular groove is arranged at the center of the triangle and used for mounting the side support ball head 2; three supporting rods 3 are respectively arranged on three vertex angles of the triangle; the middle part of the support rod 3 connected with the connecting piece 4 is provided with a deep groove ball bearing; the two ends of each support rod 3 are provided with invar steel pads 5. The reflector 1 is arranged in a supporting mirror chamber 6 and is contacted with the side supporting ball heads 2 and the invar pad 5. The connecting shafts 7 are arranged on the back surface of the supporting mirror chamber 6, are positioned in the middle and the lower part of the back surface, and are symmetrically provided with two groups of 4 connecting shafts 7.

The reflector supporting structure can realize that the micro-attitude of the reflector 1 can be automatically adjusted along with the direction of gravity after the assembly is finished, no additional stress is applied to the mirror surface, and the only deformation is the influence of the gravity of the reflector.

The invar steel pad 5 is mainly used for connecting the support rod 3 and the reflector 1 by using low-expansion invar steel because the expansion ratio difference between the microcrystalline glass and the metal is large. The side supporting ball heads 2 are made of invar steel materials, the expansion coefficient is small, the deformation of the side supporting ball heads is relatively small when the temperature difference changes, and the influence of the supporting structure on the surface shape of the reflector is reduced to the greatest extent.

The connecting shafts 7 are two sets of shafts which are vertically installed and are key connecting parts for realizing the assembly and the switching of the reflector assembly. The supporting method is a commonly used supporting method for the reflector, and is widely applied to supporting the mirror surface of the astronomical optical telescope.

The turnover switching mechanism can be seen in fig. 2 and fig. 3 (see fig. 6-fig. 8 for convenient and intuitive expression of a special perspective view), and mainly comprises a mounting plate 8, a support bracket 9, a grating ruler 10, a reading head 11, a lead screw fixing seat a12, a lead screw nut 13, a lead screw 14, a reflector assembly 15, a lead screw fixing seat B16, a worm wheel 17, a worm 18, a worm fixing seat a19, a coupling 20, a driving motor 21, a worm fixing seat B22, a guide rail a23, a slider a24, a guide rail B25, a slider B26, a rotating frame B27, a rotating frame a28 and other main key parts.

The middle position of the mounting plate 8 is provided with a circular through hole, three sides of the supporting bracket 9 are enclosed on the mounting plate 8, the mounting main parts on the parallel supporting brackets at two sides are the same, and the grating ruler 10 and the reading head 11 are additionally arranged on the parallel supporting bracket at one side. A driving motor 21 is arranged on the back plate supporting bracket on one side. The method comprises the following specific steps:

the support brackets 9 with two parallel sides are symmetrically provided with guide rails A23, the screw rod 14 is arranged on the guide rail A23, two ends of the screw rod 14 fix the screw rod 14 through a screw rod fixing seat A12 and a screw rod fixing seat B16 respectively, and one end of the screw rod is fixed and the other end of the screw rod floats. The feed screw nut 13 is directly connected with the rotating frame A28, and the floating end of the feed screw 14 is provided with a worm wheel 17.

A driving motor 21 which is a special motor is mounted on the back plate supporting bracket on one side, a mode of double output heads is adopted, namely, connecting shafts are arranged at two ends, and the driving motor 21 and the two worms 18 are connected together through two couplers 20 respectively. The worm 18 cooperating with the worm wheel 17 is fixedly mounted on the worm fixing seat a19 and the worm fixing seat B22 (see fig. 7 in detail).

Triangular supports are parallelly arranged on two sides of the circular through hole of the mounting plate 8 and used for supporting a guide rail B25, and a sliding block B26 is arranged on the guide rail B25; the slide block B26 is connected with the rotating frame B27, the slide block B24 is connected with the rotating frame A28, the rotating frame A28 and the rotating frame B27 are respectively arranged on the connecting shaft 7 at the middle part and the lower part of the back surface of the mirror assembly supporting mirror chamber 6, and therefore the mirror assembly and the overturning assembly are connected together through the connection. The worm wheel 17 is directly assembled on the screw rod 14, the driving motor 21 drives the worm 18 to rotate, the worm wheel 17 meshed with the worm wheel drives the screw rod 14 to rotate, the screw rod nut 13 is enabled to horizontally move, and therefore the rotating frame A28 is driven to move. The guide rail B25 and the guide rail A23 have a specific calculated angle, and the moving process of the lead screw nut 13 simultaneously drives the rotating frame A28, the rotating frame B27 and the connected sliding blocks A24 and B26 to move in a translation mode on the sliding block guide rail, so that the angle is turned over.

Grating chi 10 is installed on the fixing base of slider guide rail, and reading head 11 is installed on slider A24.

FIG. 2 is a position in which the mirror is at a 45 degree disposition; fig. 3 shows the reflector at 90 degrees, and the reflector assembly is kept away from the focal channel.

The translational shift mechanism is shown in assembled view in fig. 4 and 5 (see fig. 6-8 for a perspective view for ease of visual presentation). The device mainly comprises main parts such as an installation fixing plate 29, a translation guide rail C30, a translation sliding block C31, a translation worm fixing seat B32, a translation worm 33, a translation worm wheel 34, a coupler 35, a driving motor 36, a translation guide rail bracket 37, a translation guide rail D38, a translation sliding block D39, an inclined connecting block 40, a translation lead screw 41, a translation guide rail E42 and a lead screw fixing seat 43.

The turnover assembly body is arranged on the slide block 31, and the pair of translation guide rails C30 are arranged on the installation fixing plate 29 in parallel. The tumble switching mechanism is movable on a translation guide C30 that mounts the fixed plate 29.

A translation worm fixing seat B32 is fixed on the back plate supporting bracket on one side; the driving motor 36 is arranged on the translation worm fixing seat B32; meanwhile, one end of the translation lead screw 41 is also fixedly arranged on the translation worm fixing seat B32, and the other end of the translation lead screw is fixed by a lead screw fixing seat 43; the translation worm wheel 34 is fixedly arranged at one end of the translation lead screw 41; the driving motor 36 is connected with the translation worm 33 through a coupler 35; the translation guide rail bracket 37 is fixed on the mounting and fixing plate 29 and does not move together with the overturning assembly body; a translation guide rail D38 is arranged on the translation guide rail bracket 37, and a translation guide rail E42 is arranged on a back plate supporting bracket on one side; the two translation sliding blocks D39 clamp the inclined connecting block 40 in the middle and are fixedly connected into a whole, the inclined connecting block 40 is connected with a nut of the translation screw rod 41, and the two translation sliding blocks D39 are driven to simultaneously slide along the translation guide rail D38 and the translation guide rail E42 while the inclined connecting block 40 moves along the translation screw rod 41. The translation guide rail bracket 37 and the inclined connecting block 40 both have a certain angle relative to the overturning assembly body.

The driving motor 36 is operated to drive the translation worm 33 to engage the translation worm wheel 34 to rotate, thereby driving the translation lead screw 41 to rotate, and the nut thereof is connected with the inclined connecting block 40, so that the rotation motion is changed into the linear motion along with the rotation motion. Because the inclined rotating block 40 and the translation guide rail bracket 37 both have a certain angle, the horizontal movement is acted by a tangential component force, and the translation movement perpendicular to the screw shaft is realized.

The rotary switching assembly body mainly comprises main parts such as a supporting box body 44, a coded disc reading head 45, a coded disc 46, a coded disc mounting bracket 47, a direct-drive motor rotor mounting bracket 48, a stator mounting bracket 49, a direct-drive motor stator assembly 50, a direct-drive motor rotor assembly 51, a large round nut 52, a rotating shaft 53, an angular contact ball bearing A54 and an angular contact ball bearing B55.

The angular contact ball bearing A54 and the angular contact ball bearing B55 are installed face to face and used for supporting the rotating shaft 53; the rotor assembly 51 and the stator assembly 50 of the direct drive motor are respectively assembled on the rotating shaft 53 and the supporting box 44 through corresponding mounting brackets, namely a rotor mounting bracket 48 and a stator mounting bracket 49 of the direct drive motor; the code wheel 46 is mounted on the rotary shaft 53 by means of screws and a code wheel mounting bracket 47, and the reading head 45 thereof is mounted on the support case 44.

The direct drive motor works to drive the whole rotating shaft 53 to rotate, and the reading head 45 can detect the rotating angle of the coded disc 46, so that the position is detected and fed back. The translation assembly body and the overturning assembly body are arranged on the rotating shaft 53, and the integral rotation can be realized. The rotation axis 53 is a hollow axis, i.e., a path through which the reflected light from the secondary mirror passes.

The invention is not limited to the specific technical solutions described in the above embodiments, and all technical solutions formed by equivalent substitutions are within the scope of the invention as claimed.