Probe structure of vortex type edge sensor

Abstract

The invention discloses a probe structure of an eddy current type edge sensor, which comprises an eddy current type sensor, a first clamping mechanism fixedly arranged on the back surface of a first sub-mirror, a second clamping mechanism fixedly arranged on the back surface of a second sub-mirror adjacently connected with the first sub-mirror, and a U-shaped notch structure with one end, close to the second clamping mechanism, of a U-shaped block, a cantilever beam is clamped on the second clamping mechanism, the cantilever end of the cantilever beam is inserted into the notch structure, and detection components of the eddy current type sensor are fixedly arranged on the cantilever end and the upper surface and the lower surface of the notch structure respectively. The probe structure shows excellent stability under specified environmental conditions, drifting among the sensors is kept within a small range, and the probe structure has high reliability and performance consistency under temperature change and humidity fluctuation.

Description

Technical Field

[0001] The present invention belongs to the technical field of sensors, and particularly relates to a probe structure of an eddy current type edge sensor. Background Art

[0002] An edge displacement sensor is an advanced sensing device dedicated to high-precision displacement measurement for confocal or co-phasing of large-aperture segmented telescopes. In a segmented astronomical telescope system, the edge displacement sensor is mainly used to detect the relative displacement and spatial position relationship between adjacent sub-mirrors. By real-time monitoring the relative displacement data of the sub-mirrors, the sensor provides accurate feedback information for subsequent attitude adjustment of the sub-mirrors, thereby achieving precise calibration of the optical path and efficient focusing of the telescope system.

[0003] The performance indicators of the edge displacement sensor, including its measurement resolution, linearity, dynamic response speed, and anti-environmental interference ability, etc., directly determine the detection accuracy and system stability during the attitude adjustment of the sub-mirrors. As a core component of the Active Optics Maintenance System (AOMS) of an astronomical telescope, this sensor is crucial for the overall performance of the system. Especially in a large segmented mirror system, the minute displacement between adjacent sub-mirrors may significantly affect the imaging quality of the entire telescope. Therefore, the accuracy and reliability of the edge displacement sensor become an important guarantee for achieving high-resolution astronomical observations.

[0004] In addition, the design and implementation of the edge displacement sensor need to comprehensively consider various factors, including stability in complex environments (such as temperature fluctuations, vibration interference, etc.) and reliability during long-term operation. Its core technology usually combines advanced optical, capacitive or eddy current measurement principles, and can obtain displacement data in real time with nanometer-level accuracy, thus meeting the stringent requirements of astronomical telescopes for high-precision and high-stability measurement equipment. Through the precise detection and feedback of the edge displacement sensor, the telescope system can continuously optimize the spatial attitude of the sub-mirrors, ensuring the stability and imaging quality of the segmented mirror array during long-term observations. This technical solution is not only a key support for the development of modern astronomical observation equipment, but also provides important reference and technical reserves for the research and development of larger-scale segmented mirror telescopes in the future. Summary of the Invention

[0005] The present invention provides a probe structure of an eddy current edge sensor. A clamping mechanism is arranged on the back of two adjacent sub-mirrors to fix a U-shaped block and a cantilever beam on the back of the two sub-mirrors. Two parts of the eddy current sensor are respectively arranged on the U-shaped block and the cantilever beam to form a probe structure for displacement signal detection. The two clamping mechanisms are fixed on the back of the two sub-mirrors by adopting a fixed block, and the U-shaped block and the cantilever beam are clamped on the two clamping mechanisms by a three-point pressure structure combined with precision spherical contact and an adjustable spring compression mechanism.

[0006] In order to solve the above technical problems, a technical solution adopted by the present invention is: A probe structure of an eddy current edge sensor comprises an eddy current sensor, a first clamping mechanism fixedly arranged on the back of a first sub-mirror, and a second clamping mechanism fixedly arranged on the back of a second sub-mirror adjacent to the first sub-mirror, wherein a U-shaped block is clamped on the first clamping mechanism, and one end of the U-shaped block close to the second clamping mechanism is a "匚"-shaped notch structure, and a cantilever beam is clamped on the second clamping mechanism, and the cantilever end of the cantilever beam is inserted into the notch structure, and the upper and lower surfaces of the cantilever end are respectively arranged parallel to the upper and lower surfaces of the notch structure, the target plates of the eddy current sensor are respectively fixedly arranged on the upper and lower surfaces of the cantilever end, and the induction coils of the eddy current sensor are respectively fixedly arranged on the upper and lower surfaces of the notch structure.

[0007] Furthermore, the first clamping mechanism and the second clamping mechanism each include a fixed block, a screw connected to the top of the fixed block, a pressure cover plate movably mounted on the outside of the screw, a nut block threadedly connected to the screw and located above the pressure cover plate, and a spring mounted on the outside of the screw and located between the nut block and the pressure cover plate, and the U-shaped block / cantilever beam is mounted on the outside of the screw and located between the fixed block and the pressure cover plate.

[0008] Furthermore, the U-shaped block, cantilever beam and fixed block are all made of microcrystalline glass.

[0009] Furthermore, a threaded hole is provided in the top surface of the fixing block, and the bottom end of the screw rod is threadedly connected in the threaded hole.

[0010] Furthermore, the fixing block is glued and fixed on the back side of the first sub-mirror / the second sub-mirror.

[0011] Furthermore, three first spherical caps evenly distributed around the circumference are arranged on the outer side of the bottom surface of the gland plate, and spherical grooves matching the first spherical caps are arranged on the top surfaces of the U-shaped block and the cantilever beam.

[0012] Furthermore, the bottom surface of the U-shaped block is provided with three second spherical crowns distributed in a triangular shape and in contact with the back surface of the first sub-mirror.

[0013] Further, a first embedding groove is formed in the bottom surface of the U-shaped block, and the fixing block of the first clamping mechanism is located in the first embedding groove.

[0014] Further, the bottom surface of the cantilever beam is an inclined plane matching the back surface of the second sub-mirror, and three third spherical crowns in a triangular distribution and in contact with the back surface of the second sub-mirror are arranged on the bottom surface of the cantilever beam.

[0015] Further, a second embedding groove is formed in the bottom surface of the cantilever beam, and the fixing block of the second clamping mechanism is located in the second embedding groove.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. By arranging clamping mechanisms on the back surfaces of two adjacent sub-mirrors, the present invention realizes the fixation of the U-shaped block and the cantilever beam on the back surfaces of the two sub-mirrors. Two parts of the eddy current sensor are respectively arranged on the U-shaped block and the cantilever beam to form a probe structure for displacement signal detection. This probe structure shows excellent stability under specified environmental conditions, and the drift between sensors remains within a small range. This probe structure has high reliability and performance consistency under temperature changes and humidity fluctuations. 2. The present invention realizes the fixation of the two clamping mechanisms on the back surfaces of the two sub-mirrors by adopting the fixing block and adhesive connection method, without causing any change to the structure of the sub-mirrors. The clamping of the U-shaped block and the cantilever beam on the two clamping mechanisms is realized through the three-point pressure structure combined with the precise spherical surface contact and the adjustable spring compression mechanism, so that the U-shaped block and the cantilever beam can obtain stable positioning in multiple degrees of freedom, realizing uniform clamping force distribution, thereby providing stable and adjustable clamping force for the U-shaped block and the cantilever beam, which can be accurately adjusted according to actual needs to meet the use requirements under different working conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a three-dimensional structural schematic diagram of the probe structure of the present invention in the use state; Figure 2 is a three-dimensional structural schematic diagram of the probe structure of the present invention in the upward view state; Figure 3 is one of the three-dimensional structural schematic diagrams of the first clamping mechanism; Figure 4 is the other three-dimensional structural schematic diagram of the first clamping mechanism; Figure 5 is the three-dimensional structural schematic diagram of the pressure cover plate; Figure 6 is one of the three-dimensional structural schematic diagrams of the U-shaped block; Figure 7 is the other three-dimensional structural schematic diagram of the U-shaped block; Figure 8Schematic three-dimensional structure diagram of the assembled state of the pressing cover plate and the U-shaped block; Figure 9 One of the schematic three-dimensional structure diagrams of the cantilever beam; Figure 10 Another schematic three-dimensional structure diagram of the cantilever beam; Figure 11 Drift results actually measured for the probe structure of the present invention.

[0018] In the figure: 1. First clamping mechanism; 101. Fixed block; 102. Screw; 103. Pressing cover plate; 1031. First spherical crown; 104. Nut block; 105. Spring; 106. Locking nut; 2. Second clamping mechanism; 3. Cantilever beam; 301. Third spherical crown; 302. Second groove; 4. U-shaped block; 401. Spherical groove; 402. Second spherical crown; 403. First groove; 5. Induction coil; 6. Target plate; 100. First sub-mirror; 200. Second sub-mirror. Detailed implementation manners

[0019] The following elaborates on the preferred embodiments of the present invention in conjunction with the accompanying drawings, so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making the protection scope of the present invention more clearly defined.

[0020] It should be noted that when a component is referred to as "installed on" another component, it can be directly on the other component or there may also be an intermediate component. When a component is considered to be "arranged on" another component, it can be directly arranged on the other component or there may be an intermediate component at the same time. When a component is considered to be "fixed to" another component, it can be directly fixed to the other component or there may be an intermediate component at the same time.

[0021] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present invention belongs. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "or / and" used herein includes any and all combinations of one or more of the related listed items.

[0022] See the appendix Figures 1 to 10A probe structure of an eddy current edge sensor includes an eddy current sensor, a first clamping mechanism 1 fixedly arranged on the back of a first sub-mirror 100, and a second clamping mechanism 2 fixedly arranged on the back of a second sub-mirror 200 adjacent to the first sub-mirror 100. The first clamping mechanism 1 clamps a U-shaped block 4, and one end of the U-shaped block 4 close to the second clamping mechanism 2 is a "匚"-shaped notch structure. The second clamping mechanism 2 clamps a cantilever beam 3, and the cantilever end of the cantilever beam 3 is inserted into the notch structure, and the upper and lower surfaces of the cantilever end are respectively arranged parallel to the upper and lower surfaces of the notch structure. The target plate 6 of the eddy current sensor is respectively fixedly arranged on the upper and lower surfaces of the cantilever end, and the induction coil 5 of the eddy current sensor is respectively fixedly arranged on the upper and lower surfaces of the notch structure.

[0023] like Figure 3 and Figure 4 As shown, the first clamping mechanism 1 includes a fixed block 101, a screw 102 inserted and fixed in the top of the fixed block 101, a gland plate 103 movably sleeved on the outside of the screw 102, a nut block 104 threadedly connected to the screw 102 and located above the gland plate 103, and a spring 105 sleeved on the outside of the screw 102 and located between the nut block 104 and the gland plate 103. Among them, the U-shaped block 4, the cantilever beam 3 and the fixed block 101 are all made of microcrystalline glass. With its low thermal expansion coefficient, microcrystalline glass can significantly reduce the impact of ambient temperature fluctuations on mechanical structures and sensor performance, thereby ensuring that the spliced ​​telescope system continues to maintain excellent stability and reliability in harsh environments.

[0024] In an astronomical telescope, the precise positioning of the cantilever beam 3 and the U-shaped block 4 on the two adjacent sub-mirrors is crucial to ensure system performance. In this process, the fixing block 101 plays an important role as a key component. The bottom of the U-shaped block 4 and the cantilever beam 3 are both equipped with a fixing block 101, which plays the role of fixing the overall structure of the eddy current sensor on the back of the sub-mirror. Specifically, the fixing block 101 adopts a disc structure, and its bottom is fixed to the back of the sub-mirror by DP460 epoxy resin adhesive to ensure that the component maintains stable positioning accuracy and sufficient mechanical strength during long-term use.

[0025] The internal structure design of the fixing block 101 is closely related to the installation and fastening method of the screw rod 102 to ensure the reliability and stability of the system when subjected to external forces. In this embodiment, a threaded hole is opened in the center of the top surface of the fixing block 101, and the bottom end of the screw rod 102 is threadedly connected to the threaded hole. Figure 3 As shown, the screw rod 102 is also threadedly connected with a locking nut 106 located on the top surface of the fixing block 101 , and the screw rod 102 can be pulled upward by the locking nut 106 to achieve tightening and preventing the screw rod 102 from loosening on the fixing block 101 .

[0026] Four U-shaped blocks 4 are sleeved outside the screw rod 102 of the first clamping mechanism 1 and are located between the corresponding fixed block 101 and the pressure cover plate 103. Specifically, as Figure 5 shown, a through hole is provided at the center of the pressure cover plate 103, so that it is sleeved outside the screw rod 102 in a clearance fit manner. Three equal-length extension arms are integrally provided on the outer side wall of the pressure cover plate 103. A first spherical crown 1031 is provided on the bottom surface of each extension arm, so that the three first spherical crowns 1031 are evenly distributed circumferentially around the axis of the pressure cover plate 103. A vertically through center through hole is provided at one end of the U-shaped block 4 away from the cantilever beam 3. The inner diameter of the center through hole is larger than the outer diameter of the screw rod 102 located therein. Since the temperature change at the application site of the astronomical telescope system is often relatively drastic, the probe body is made of glass-ceramics with a very small coefficient of thermal expansion, but the thermal deformation of the metal screw rod 102 may be relatively large. Therefore, enough deformation clearance needs to be left between the side wall of the center through hole and the outer surface of the screw rod 102.

[0027] As Figure 6 shown, a spherical groove 401 matching the first spherical crown 1031 is provided on the top surface of the U-shaped block 4. By rotating the position of the nut block 104 on the screw rod 102, the compression amount of the spring 105 can be correspondingly adjusted, so as to adjust the clamping force applied to the top of the pressure cover plate 103. As Figure 5 and Figure 8 shown, the three first spherical crowns 1031 at the bottom of the pressure cover plate 103 are in spherical contact fit with the spherical groove 401 on the top surface of the U-shaped block 4, and pressure can be applied through three independent contact points, so that the object can obtain stable positioning in multiple degrees of freedom, realizing uniform clamping force distribution, thereby providing a stable and adjustable clamping force for the U-shaped block 4, which can be accurately adjusted according to actual needs to meet the use requirements under different working conditions. Since the three-point pressure structure provides a uniform pressure distribution of three contact points, it can ensure the positioning consistency during each assembly, so as to achieve excellent self-centering ability, and can automatically eliminate the positioning error caused by manufacturing error or assembly error, and has good repeatability. Compared with other complex clamping or positioning devices, the three-point pressure mechanism has a simple design, a compact structure, is easy to manufacture and assemble, and can significantly reduce costs during installation and maintenance. This three-point pressure structure combines precise spherical contact and an adjustable spring compression mechanism, which not only ensures high positioning accuracy, but also provides a reliable and stable clamping force.

[0028] In this embodiment, the nut block 104 adopts a T-shaped nut. The top end of the spring 105 is sleeved outside the rod end of the T-shaped nut. A counterbore is provided at the center of the pressure cover plate 103 for accommodating the bottom end of the spring 105.

[0029] As Figure 7As shown, three second spherical crowns 402 distributed in an equilateral triangle are arranged on the bottom surface of the U-shaped block 4. The three second spherical crowns 402 distributed in a triangle are in contact with the back surface of the first sub-mirror 100, and are evenly distributed in a circumferential manner around its axis at a central angle of 120°, achieving stable three-point contact positioning with the back surface of the first sub-mirror 100, further improving the overall stability and repeatability of the system, and providing a reliable guarantee for precise measurement and regulation.

[0030] The structural composition and working form of the second clamping mechanism 2 are the same as those of the first clamping mechanism 1. Similarly, as Figure 9 and Figure 10 shown, a central through hole with the same diameter is also opened at one end of the cantilever beam 3 away from the U-shaped block 4. The screw 102 in the second clamping mechanism 2 is located in this central through hole and has a gap with the inner wall of the central through hole to meet the requirement of large thermal deformation of the screw 2 in the temperature field. Similarly, a spherical groove 401 matching the first spherical crown 1031 is also arranged on the top surface of the cantilever beam 3. By adopting a three-point pressure structure combined with a precise spherical surface contact and an adjustable spring compression mechanism, the clamping and positioning of the cantilever beam 3 on the back surface of the second sub-mirror 200 are realized.

[0031] Since the back surface of the first sub-mirror 100 is a horizontal plane, while the back surface of the second sub-mirror 200 is an inclined plane, there is an angular difference between the two. And the cantilever end of the cantilever beam 3 needs to be parallel to the notch structure of the U-shaped block 4 to meet the assembly and use requirements of the eddy current sensor. Therefore, the bottom surface of the cantilever beam 3 is an inclined plane matching the back surface of the second sub-mirror. Through the assembly of this inclined plane with the back surface of the second sub-mirror 200, the dihedral angle error between the sub-mirrors of the spliced mirror is compensated, ensuring that the induction coil 5 in the U-shaped block 4 and the target plate 6 in the cantilever beam 3 are in a parallel state during the initial installation; and three third spherical crowns 301 distributed in a triangle and in contact with the back surface of the second sub-mirror 200 are arranged on the bottom surface of the cantilever beam 3, and are evenly distributed in a circumferential manner around the axis of the central through hole of the cantilever beam 3 at a central angle of 120°, achieving stable three-point contact positioning with the back surface of the second sub-mirror 200, thereby improving the positioning accuracy and stability of the overall structure.

[0032] A first embedding groove 403 is formed in the bottom surface of the U-shaped block 4, and the fixing block 101 of the first clamping mechanism 1 is located in the first embedding groove 403. A second embedding groove 302 is formed in the bottom surface of the cantilever beam 3, and the fixing block 101 of the second clamping mechanism 2 is located in the second embedding groove 302. To meet the high-precision requirements, the inner diameters of the first embedding groove 403 and the second embedding groove 302 are slightly larger than the outer diameter of the fixing block 101, so that there are gaps in the horizontal direction between the inner wall of the first embedding groove 403 inside the U-shaped block 4 and the outer wall of the fixing block 101 inside it, and between the inner wall of the second embedding groove 302 inside the cantilever beam 3 and the outer wall of the fixing block 101 inside it. Due to the dihedral angle between the first sub-mirror 100 and the second sub-mirror 200, this horizontal gap can finely adjust the displacement of the cantilever beam 3 in the height direction, enabling the eddy current sensor to always be in the best working state, thereby providing a stable and efficient output signal.

[0033] Target plates 6 made of aluminum blocks are respectively installed on the upper and lower side surfaces of the cantilever end of the cantilever beam 3. The target plates 6 cooperate with the induction coils 5 provided on the U-shaped block 4 to accurately capture the change in the relative position between the cantilever beam 3 and the U-shaped block 4 by detecting the generation and change trend of eddy currents. Therefore, the processing of the upper and lower electrode plates (i.e., the upper and lower side surfaces of the cantilever end) of the cantilever beam 3 needs to ensure a certain roughness and flatness. Preferably, installation grooves are formed on the upper and lower inner side surfaces of the notch structure of the U-shaped block 4, and the substrate of the induction coil 5 is pasted in the installation grooves, and its two leads are led out from the long grooves on the side.

[0034] In the actual performance experiment, the detection circuit module of the eddy current sensor and the U-shaped probe composed of the induction coil 5 and the U-shaped block 4 are used in combination to test the temperature stability of the overall system. Through continuous testing of the probe for 10 hours, its performance drift under changing environmental conditions is monitored. The results show that under the control conditions of a temperature of 40 ± 0.3 °C and a relative humidity (RH) of 8 - 18%, the drift value of the sensor is about 60 nm. Further analysis shows that the drift range of four sets of independent sensors under the same test conditions is from -63 nm to 42 nm. This result fully demonstrates that the adopted probe structure exhibits excellent stability under the specified environmental conditions, and the drift between each set of sensors remains within a small range, verifying the high reliability and performance consistency of the probe structure under temperature changes and humidity fluctuations.

[0035] As Figure 11 shown, after the sensor is completely installed, a 4-day constant temperature test is carried out in the laboratory, and the measured sensor drift is 4.0 nm. Assuming that the drift of the sensor is proportional to the test duration, the time drift is 7 nm / week. This result fully demonstrates that the adopted probe structure exhibits excellent stability under the specified environmental conditions, verifying the high reliability of the probe structure under temperature changes.

[0036] The technical features of the above-described embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the various technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this specification.

[0037] The above is only an embodiment of the present invention, and thus does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the content of the specification and drawings of the present invention, or directly or indirectly applied in other related technical fields, shall similarly be included in the patent protection scope of the present invention.

Claims

1. The probe structure of an eddy current type edge sensor, characterized in that: It includes an eddy current sensor, a first clamping mechanism fixedly arranged on the back side of a first sub-mirror, and a second clamping mechanism fixedly arranged on the back side of a second sub-mirror adjacent to the first sub-mirror. The first clamping mechanism clamps a U-shaped block, and one end of the U-shaped block close to the second clamping mechanism is a "匚"-shaped notch structure. The second clamping mechanism clamps a cantilever beam, and the cantilever end of the cantilever beam is inserted into the notch structure, and the upper and lower surfaces of the cantilever end are respectively arranged parallel to the upper and lower surfaces of the notch structure. The target plates of the eddy current sensor are respectively fixedly arranged on the upper and lower surfaces of the cantilever end, and the induction coils of the eddy current sensor are respectively fixedly arranged on the upper and lower surfaces of the notch structure.

2. The probe structure of the eddy current type edge sensor according to claim 1, characterized in that: The first clamping mechanism and the second clamping mechanism both include a fixed block, a screw connected to the top of the fixed block, a pressure cover plate movably mounted on the outside of the screw, a nut block threadedly connected to the screw and located above the pressure cover plate, and a spring mounted on the outside of the screw and located between the nut block and the pressure cover plate. The U-shaped block / cantilever beam is mounted on the outside of the screw and located between the fixed block and the pressure cover plate.

3. The probe structure of the eddy current type edge sensor according to claim 2, characterized in that: The U-shaped block, cantilever beam and fixed block are all made of microcrystalline glass.

4. The probe structure of the eddy current type edge sensor according to claim 2, characterized in that: A threaded hole is provided in the top surface of the fixing block, and the bottom end of the screw rod is threadedly connected in the threaded hole.

5. The probe structure of the eddy current type edge sensor according to claim 2, wherein: The fixing block is glued and fixed on the back side of the first sub-mirror / the second sub-mirror.

6. The probe structure of the eddy current type edge sensor according to any one of claims 2 to 5, characterized in that: The outer side of the bottom surface of the gland plate is provided with three first spherical caps evenly distributed around the circumference, and the top surfaces of the U-shaped block and the cantilever beam are provided with spherical grooves matching the first spherical caps.

7. The probe structure of the eddy current type edge sensor according to any one of claims 2 to 5, characterized in that: The bottom surface of the U-shaped block is provided with three second spherical crowns distributed in a triangle and in contact with the back surface of the first sub-mirror.

8. The probe structure of the eddy current type edge sensor according to claim 7, characterized in that: A first embedding groove is provided on the bottom surface of the U-shaped block, and a fixing block of the first clamping mechanism is located in the first embedding groove.

9. The probe structure of the eddy current type edge sensor according to any one of claims 2 to 5, characterized in that: The bottom surface of the cantilever beam is an inclined plane matching the back surface of the second sub-mirror, and three third spherical crowns distributed in a triangular shape and in contact with the back surface of the second sub-mirror are arranged on the bottom surface of the cantilever beam.

10. The probe structure of the eddy current type edge sensor according to claim 9, characterized in that: A second embedding groove is provided on the bottom surface of the cantilever beam, and a fixing block of the second clamping mechanism is located in the second embedding groove.

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