Counterweight supporting structure for adjusting surface shape of reflecting mirror

Abstract

The invention discloses a counterweight supporting structure for adjusting the surface shape of a reflecting mirror, and the structure comprises an insert which is connected in a reflecting mirror body, and a ball socket structure is formed in the insert; the support is connected with the bottom plate through screws; the differential structure comprises a ball head sliding block, and a ball head of the ball head sliding block is matched with the ball socket structure; and the balance weight structure can form a lever fulcrum to provide radial supporting force for the reflector body. According to the balance weight supporting structure for adjusting the surface shape of the reflecting mirror, on one hand, the radial supporting force on the mirror body can be adjusted through the balance weight structure, and the gravity influence of the mirror body is completely balanced; on the other hand, the axial displacement can be finely adjusted through a differential thread structure, the adjusting precision is superior to 1 micron, and the high-low point surface shape defect of the mirror surface can be made up; compared with an existing balance weight structure or a surface-shaped active adjusting structure, the two-way adjusting composite function is achieved, and meanwhile the structure is simpler, the supporting state is stable, the adjusting precision is high, and operation is easy and convenient.

Description

Technical Field

[0001] The present invention relates to the field of aerospace remote sensing technology, in particular to a balancing weight support structure for adjusting the surface shape of a reflector. Background Art

[0002] The optical mirror surface of a large-aperture ground-based mirror requires a support structure to overcome deformation due to gravity, and the surface shape can be actively adjusted through a fine-tuning structure after the mirror surface creeps and the accuracy degrades. Currently, the main method for balancing gravity for large mirrors is to use a counterweight structure to provide radial support force, and the active surface shape adjustment uses an actuator to provide axial support force to compensate for the surface shape. The actuator support structure requires high-precision piezoelectric devices, which are complex and expensive. In addition, the multi-point adjustment closed-loop control algorithm is extremely difficult to implement, and is generally only used in very expensive ultra-large telescopes and space mirrors. The counterweight structure is relatively simple and easy to operate, but its main drawback is that it cannot achieve axial fine-tuning to compensate for surface defects.

[0003] The prior art closest to the present invention is the utility model patent with publication number "CN 203422517 U", which describes a lever-weight mechanism with both axial and lateral support forces. Figure 1 As shown, it consists of a lever, a fulcrum, a weight and a front end ball head, and has two characteristic levers: a bottom supporting lever and a side supporting lever; wherein, the bottom supporting weight is arranged at one end of the bottom supporting lever, and the side supporting weight is arranged at one end of the side supporting lever; at the same time, a floating bracket is provided, which is mounted on the base through a pair of equal-length arms, and the base is mounted on the mirror chamber; the fulcrum of the bottom supporting lever is set on the base, and its action point is set on the floating bracket; the floating bracket then transmits the force to the front end ball head through the side supporting lever; the fulcrum of the side supporting lever is set on the floating bracket, and its action point is set on the support in the opening on the back of the reflector.

[0004] The shortcomings and deficiencies of the above-mentioned device are: a) Complex supporting structure: The assembly of multiple sets of weight structures is difficult and the processing cost is high; b) Inability to achieve active adjustment: The device can only balance gravity. After the weights are installed, the supporting force basically does not change, and active adjustment cannot be achieved later; c) Insufficient adjustment accuracy: It is impossible to achieve high-precision axial adjustment and compensate for mirror surface defects.

[0005] Based on the above technical problems, technicians in this field urgently need to develop a balancing weight support structure with simple structure, high control accuracy, convenient adjustment, low cost, and suitable for adjusting the surface shape of large-aperture reflectors. Summary of the Invention

[0006] The purpose of the present invention is to provide a balancing weight support structure which has a simple structure, high control precision, convenient adjustment, low cost and is suitable for adjusting the surface shape of a large-aperture reflector.

[0007] In order to achieve the above object, the present invention provides the following technical solutions:

[0008] A balancing weight support structure for adjusting the surface shape of a reflector according to the present invention comprises:

[0009] An inlay is connected to the reflector body, and a ball-and-socket structure is formed in the inlay;

[0010] The support is connected to the base plate by screws;

[0011] The support structure also includes:

[0012] A differential structure comprising a ball slider, wherein the ball head of the ball slider is adapted to the ball and socket structure;

[0013] The balance weight structure can form a lever fulcrum to provide radial support force for the reflector body.

[0014] Furthermore, a ball head end cover is provided on the outside of the ball head slider, and the ball head can be controlled to rotate freely 360° by adjusting the tightening torque of the ball head end cover.

[0015] Furthermore, the differential structure further comprises a retaining frame, and the ball head slider can move forward and backward in a square groove of the retaining frame;

[0016] A differential screw, the front end of which is connected to the ball slider via a reverse-rotating thread, and the middle of the differential screw is connected to the retaining frame via a forward-rotating thread;

[0017] An adjusting hand wheel is provided at the rear end of the differential screw and is fixed by a hand wheel screw.

[0018] Furthermore, the balancing weight structure includes a self-aligning bearing capable of 360° free rotation, wherein the outer ring of the self-aligning bearing cooperates with the support, and the inner ring cooperates with the retaining frame;

[0019] The inner and outer rings of the self-aligning bearing are respectively fixed with bearing retaining rings;

[0020] It also includes a counterweight block, which can be adjusted forward and backward with the retaining frame through threads, and a counterweight block stop ring is provided at one end of the counterweight block away from the support.

[0021] Furthermore, an arrow is formed on the end of the differential screw.

[0022] Furthermore, the counterweight block stop ring is provided with four cylindrical holes, which are used in conjunction with a threaded wrench to lock the counterweight block.

[0023] Furthermore, the adjustment hand wheel is made of transparent material, and the outer surface is engraved with angle lines and formed with small scales and large scales, wherein each small scale is 5°, and each large scale is 15°.

[0024] Preferably, a locking screw is provided on the differential structure, and the locking screw is used to lock and fix the differential structure after adjustment is completed.

[0025] In the above technical solution, the present invention provides a balancing weight support structure for adjusting the reflector surface shape, which has the following beneficial effects:

[0026] The present invention discloses a balancing weight support structure for adjusting the surface shape of a reflector. On the one hand, the balancing weight structure can adjust the radial support force on the mirror body, completely balancing the gravity of the mirror body. On the other hand, the differential thread structure can fine-tune the axial displacement with an adjustment accuracy of better than 1 μm, which can compensate for the surface shape defects of the mirror surface at high and low points.

[0027] Compared with the existing balancing weight structure or surface shape active adjustment structure, the present invention realizes the two-way adjustment compound function while having a simpler structure, a more stable supporting state, a high adjustment accuracy and easy operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments described in the present invention. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0029] Figure 1 It is a schematic diagram of the prior art mentioned in the background technology of the present invention;

[0030] Figure 2 A cross-sectional view of a balancing weight support structure for adjusting the surface shape of a reflector provided by an embodiment of the present invention;

[0031] Figure 3 A side view of a partial structure of a balancing weight support structure for adjusting the surface shape of a reflector provided in an embodiment of the present invention.

[0032] Description of reference numerals:

[0033] 1. Inlay; 2. Ball head slider; 3. Ball head end cap; 4. Bearing retaining ring; 5. Self-aligning bearing; 6. Cage; 7. Differential screw; 8. Locking screw; 9. Counterweight; 10. Counterweight retaining ring; 11. Adjusting handwheel; 12. Handwheel screw; 13. Support; 14. Base plate; 15. Reflector body;

[0034] 7-1, arrow;

[0035] 10-1, cylindrical hole;

[0036] 11-1, small scale; 11-2, large scale. DETAILED DESCRIPTION

[0037] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0038] See also Figures 2 and 3 As shown;

[0039] A balancing weight support structure for adjusting the surface shape of a reflector according to the present invention comprises:

[0040] The inlay 1 is connected to the reflector body 15 by gluing the cylindrical surface, and a ball-and-socket structure is formed in the inlay 1;

[0041] The support 13, the entire support structure is connected to the base plate 14 by screws. The base plate 14 serves as the mounting base of the reflector assembly and has high strength;

[0042] The support structure also includes:

[0043] A differential structure comprising a ball slider 2, wherein the ball head of the ball slider 2 is adapted to the ball and socket structure;

[0044] The balancing weight structure can form a lever fulcrum to provide radial support force for the reflector body 15.

[0045] As a further introduction to this embodiment, a ball head end cover 3 is provided on the outside of the ball head slider 2, and by adjusting the tightening torque of the ball head end cover 3, the ball head can be controlled to rotate freely 360° without obvious shaking.

[0046] As a further introduction to this embodiment, the differential structure further includes a retaining frame 6, and the ball head slider 2 can move back and forth in the square groove of the retaining frame 6;

[0047] The differential screw 7 has a front end connected to the ball slider 2 via a reverse thread, and the middle of the differential screw 7 is connected to the retaining frame 6 via a forward thread;

[0048] The rear end of the differential screw 7 is provided with an adjustment handwheel 11, which is fixed by a handwheel screw 12. For each rotation of the adjustment handwheel 11 (forward rotation as an example), the differential screw 7 rotates one turn forward relative to the retaining frame 6 and one turn counterclockwise relative to the ball slider 2. The distance the ball slider 2 advances relative to the retaining frame 6 is the difference in the pitch of the two oppositely directed threads.

[0049] As a further introduction to this embodiment, the balancing weight structure includes a self-aligning bearing 5 as a fulcrum, which can achieve 360° free rotation. The outer ring of the self-aligning bearing 5 cooperates with the support 13, and the inner ring cooperates with the retainer 6;

[0050] The inner and outer rings of the self-aligning bearing 5 are respectively fixed with bearing retaining rings 4;

[0051] It also includes a counterweight 9, which can be adjusted forward and backward with the retaining frame 6 through threads, providing radial support force to the reflector body 15 through the lever fulcrum, and a counterweight stop ring 10 is provided at the end of the counterweight 9 away from the support 13.

[0052] The radial support adjustment principle is a lever structure. The weight of the reflector body 15 acts evenly on the ball head structure of the inlay 1, which serves as one end of the balance lever. The weight of the counterweight 9 acts on the retaining frame 6, which serves as the other end of the balance lever. The self-aligning bearing 5 serves as the fulcrum of the balance lever. During the design, calculations are made to ensure that the product of the weight of the reflector body 15 and the distance from the fulcrum is equal to the product of the weight of the counterweight 9 and the distance from the fulcrum, thereby achieving lever balance.

[0053] As a further introduction to this embodiment, an arrow 7 - 1 is formed at the end of the differential screw 7 .

[0054] As a further introduction to this embodiment, the counterweight block retaining ring 10 is provided with four cylindrical holes 10 - 1 , which are used in conjunction with a threaded wrench to lock the counterweight block 9 .

[0055] As a further introduction to this embodiment, the adjusting hand wheel 11 is made of transparent material, and the outer surface is engraved with angle lines, and is formed with small scales 11-1 and large scales 11-2, wherein each small scale 11-1 is 5°, and each large scale 11-2 is 15°.

[0056] The axial support adjustment principle is a differential mechanism. Assuming the forward pitch is designed to be 1.25mm and the reverse pitch is designed to be 1.20mm, each rotation of the differential screw 7 causes the ball slider 2 to move 0.05mm, reducing the feed rate by a factor of 25. By aligning the scale line on the adjustment handwheel 11 with the position of the arrow 7-1 marked on the retaining frame 6, axial fine-tuning of the ball slider 2 by one small grid (5°) moves the ball slider 2 by 0.7μm, resulting in an axial adjustment accuracy of better than 1μm. During actual adjustment, axial fine-tuning of the differential mechanism can compensate for high and low point defects in the mirror surface at the support point.

[0057] As a preferred technical solution of this embodiment, a locking screw 8 is provided on the differential structure, and after the adjustment is completed, it is locked and fixed by the locking screw 8, so as to keep the entire supporting structure stable.

[0058] The counterweight 9 is designed with a counterweight stop ring 10. By adjusting the threaded fit of the counterweight 9 on the retainer 6, the distance between the counterweight 9 and the lever fulcrum can be adjusted, thereby adjusting the radial support force. After adjustment, the counterweight stop ring 10 is tightened using the double-nut locking principle. The counterweight stop ring 10 is designed with four cylindrical holes 10-1 for easy use with a dedicated threaded wrench, providing a larger locking torque and more convenient operation.

[0059] like Figure 2 As shown, the implementation steps of the adjustment scheme of the present invention are as follows:

[0060] Bonding the inlay 1 and the reflector body 15 together;

[0061] The ball head slider 2 is installed into the ball socket of the insert 1 and fixed by tightening the screws between the ball head end cover 3 and the insert 2;

[0062] Install the self-aligning bearing 5 onto the retainer 6, and then install the whole onto the support 13. The self-aligning bearing 5 is locked by the inner and outer bearing retaining rings 4.

[0063] Adjust the relative position of the reflector body 15 and the base plate 14 so that the square hole at the front end of the retainer 6 is aligned with the square block at the rear end of the ball head slider 2. Adjust the insertion depth and fix the support 13 and the base plate 14 with screws.

[0064] Align the threaded position of the retainer 6 and screw in the differential screw 7. After adjusting it into place, tighten the locking screw 8.

[0065] Install the counterweight 9 onto the retaining frame 6 and fix the counterweight stop ring 10 after adjusting it into place;

[0066] Install the adjusting hand wheel 11.

[0067] Method for adjusting the radial support force: first loosen the counterweight stop ring 10 with a special threaded wrench, adjust the front and rear position of the counterweight by matching the threads, and re-fix the counterweight stop ring 10 after it is in place;

[0068] Axial support displacement adjustment method: record the alignment position of the arrow 7-1 on the current retainer 6 and the dial, first loosen the locking screw 8 with a hexagonal wrench, then calculate the adjustment amount according to the surface detection result, rotate the adjustment handwheel 11 according to the minimum scale, and re-tighten the locking screw 8 after it is in place.

[0069] The above description is merely illustrative of certain exemplary embodiments of the present invention. It goes without saying that those skilled in the art will be able to modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and description are illustrative in nature and should not be construed as limiting the scope of protection of the claims.

Claims

1. A balancing weight support structure for adjusting the surface shape of a reflector, characterized in that: The support structure includes: An inlay (1) is connected to the reflector body (15), and a ball-and-socket structure is formed in the inlay (1); A support (13) connected to the base plate (14) via screws; The support structure also includes: A differential structure comprising a ball head slider (2), wherein the ball head of the ball head slider (2) is adapted to the ball socket structure; A balancing weight structure can form a lever fulcrum to provide radial supporting force for the reflector body (15).

2. A balancing weight support structure for adjusting the reflector surface shape according to claim 1, characterized in that: A ball head end cover (3) is provided on the outside of the ball head slider (2), and the ball head can be controlled to rotate freely 360 degrees by adjusting the tightening torque of the ball head end cover (3).

3. The balancing weight support structure for adjusting the reflector surface shape according to claim 1, characterized in that: The differential structure further comprises a retaining frame (6), and the ball head slider (2) is capable of moving forward and backward in a square groove of the retaining frame (6); A differential screw (7), the front end of which is connected to the ball head slider (2) via a reverse-rotating thread, and the middle of the differential screw (7) is connected to the retaining frame (6) via a forward-rotating thread; The rear end of the differential screw (7) is provided with an adjusting hand wheel (11) which is fixed by a hand wheel screw (12).

4. A balancing weight support structure for adjusting the reflector surface shape according to claim 3, characterized in that: The balancing weight structure includes a self-aligning bearing (5) capable of achieving 360-degree free rotation, wherein the outer ring of the self-aligning bearing (5) cooperates with the support (13), and the inner ring cooperates with the retaining frame (6); The inner and outer rings of the self-aligning bearing (5) are respectively fixed with bearing stop rings (4); It also includes a counterweight (9), wherein the counterweight (9) and the retaining frame (6) can be adjusted forward and backward via threads, and a counterweight stop ring (10) is provided at one end of the counterweight (9) away from the support (13).

5. The balancing weight support structure for adjusting the reflector surface shape according to claim 3, characterized in that: An arrow (7-1) is formed at the end of the differential screw (7).

6. The balancing weight support structure for adjusting the reflector surface shape according to claim 4, characterized in that: The counterweight block stop ring (10) is provided with four cylindrical holes (10-1) for locking the counterweight block (9) in cooperation with a threaded wrench.

7. The balancing weight support structure for adjusting the reflector surface shape according to claim 3, characterized in that: The regulating hand wheel (11) is made of transparent material, and has angle lines carved on its outer surface, and is formed with small scales (11-1) and large scales (11-2), wherein each small scale (11-1) is 5°, and each large scale (11-2) is 15°.

8. A balancing weight support structure for adjusting the surface shape of a reflector according to any one of claims 1 to 7, characterized in that: The differential structure is provided with a locking screw (8), and is locked and fixed by the locking screw (8) after adjustment is completed.

Images