Miniaturized three-axis fiber-optic gyroscope

Abstract

The invention provides a miniaturized three-axis fiber-optic gyroscope. The miniaturized three-axis fiber-optic gyroscope comprises a bracket, three shielding ring assemblies, a 1 * 3 coupler, a light source driving plate, a light source, an adapter plate, a 2 * 2 coupler assembly, a front amplifier circuit board, a detector assembly, a host circuit board and an electric connector. The X-axis shielding ring assembly and the Y-axis shielding ring assembly are embedded on the two side walls of the support outside the support respectively, the light source driving plate and the light source are installed on the other side wall of the support outside the support, and the Z-axis shielding ring assembly is contained in the support. The adapter plate, the front amplifier circuit board and the host circuit board are installed in the support, the adapter plate is used for optical fiber coiling, and the detector assembly is arranged on the front amplifier circuit board. The heating device is arranged on the outer side of the product, so that the heat of the heating device can directly interact with the external environment, and the influence of the heat on the sensitive element is reduced; the optical path disc mounting surface is concentrated on the adapter plate in the product and is far away from the heating component, so that the disc mounting path is optimized, the disc mounting of the optical fiber on other surfaces is reduced, and the overall size of the gyroscope is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of three-axis fiber optic gyroscopes, and in particular relates to a miniaturized three-axis fiber optic gyroscope. Background Art

[0002] Fiber optic gyroscope is a fully solid-state inertial measurement instrument based on the Sagnac effect. It has the advantages of impact resistance, high sensitivity, long life, large dynamic range, and short startup time. It has been widely used in inertial navigation systems. The three-axis gyroscope has gradually occupied an important position in inertial navigation due to its high degree of integration, low power consumption, and price advantage. However, since the fiber optic ring, the core component of the fiber optic gyroscope, is extremely sensitive to temperature, when there is a temperature distribution gradient that changes with time and space along the optical fiber, the fiber optic gyroscope will produce a thermally induced non-reciprocal phase difference, the so-called Shupe effect. Therefore, during the use of the fiber optic gyroscope, the complex and changeable temperature field of the outside world will cause the fiber optic gyroscope output to have a zero bias error, especially for the miniaturized three-axis fiber optic gyroscope, which is restricted by volume and the internal temperature field of the product is more complex and harsh.

[0003] Due to volume constraints, the internal heating components of traditional miniaturized three-axis fiber optic gyroscopes will produce a large temperature rise in a small, enclosed space, causing the sensitive coils to be affected by heat radiation and produce non-reciprocal phase differences, which in turn affects product performance and also limits the level of product miniaturization. Summary of the invention

[0004] The applicant found that the solutions to the internal heat of miniaturized three-axis fiber optic gyroscopes are generally: reduce the power consumption of the circuit board, use integrated devices, and use thermal grease to export the heat-generating devices through the cover plate. However, applying thermal grease on the circuit board greatly increases the difficulty of debugging and the difficulty of disassembly and assembly. The heat must be dissipated to the outside through the thermal grease, which adds an intermediate link and often has poor heat dissipation effects. In addition, the gyroscope mounting surface is often distributed on several surfaces, resulting in a complex mounting path, which can lead to fiber breakage or excessive loss, and is not conducive to product miniaturization. Therefore, for miniaturized three-axis gyroscopes, it is a technical difficulty to balance the rationality and operability of the optical path mounting.

[0005] The purpose of the present invention is to solve the problem of heat concentration in the internal heating device of the miniaturized three-axis fiber optic gyroscope in the prior art, which affects the product performance and miniaturization, and provide a miniaturized three-axis fiber optic gyroscope. The present invention adopts an open structure as a whole, and the heating devices (circuit board, light source) are directly distributed on the surface of the product, directly interacting with the external environment, reducing the radiation of heat to the sensitive coil; miniaturized optical devices are selected to concentrate the optical path coiling surface on the internal adapter board of the product, away from the heating components, optimize the coiling path, reduce the coiling of optical fiber on other surfaces, and improve the utilization efficiency of other surfaces.

[0006] To achieve the above purpose, the technical solution provided by the present invention is:

[0007] A miniaturized three-axis fiber optic gyroscope includes a bracket, three shielding ring assemblies, a 1x3 coupler, a light source driving board, a light source, an adapter board, a 2x2 coupler assembly, a front amplifier circuit board, a detector assembly, a host circuit board and an electrical connector;

[0008] The bracket is used to install the three shielding ring assemblies, the 1x3 coupler, the light source driving board, the light source, the adapter board, the 2x2 coupler assembly, the front amplifier circuit board, the detector assembly, the host circuit board and the electrical connector. The bracket is in the shape of a rectangular parallelepiped with an open top and includes a first side wall and a second side wall and a third side wall adjacent to the first side wall;

[0009] The three shielding ring assemblies are respectively an X-axis shielding ring assembly, a Y-axis shielding ring assembly and a Z-axis shielding ring assembly, each comprising a waveguide, an optical fiber ring, and a shielding seat and a shielding cover made of magnetic material, the optical fiber ring is accommodated in an annular cavity between an inner ring and an outer ring of the shielding seat, the waveguide is mounted to the inner ring of the shielding seat, the shielding cover covers the shielding seat to magnetically shield the optical fiber ring, the X-axis shielding ring assembly and the Y-axis shielding ring assembly are respectively embedded on the first side wall and the second side wall of the bracket through the shielding seat outside the bracket, and the Z-axis shielding ring assembly is accommodated in the bracket;

[0010] The 1x3 coupler, light source driving board and light source are embedded on the third side wall of the bracket outside the bracket; the adapter board, front-end circuit board and host circuit board are installed in the bracket above the Z-axis shielding ring assembly in sequence, the adapter board is used for optical fiber coiling, and the electrical connector is used to electrically connect the gyroscope to the outside; the 2x2 coupler assembly includes an X-axis 2x2 coupler, a Y-axis 2x2 coupler and a Z-axis 2x2 coupler, and are arranged on the adapter board between the adapter board and the front-end circuit board; the detector assembly includes an X-axis detector, a Y-axis detector and a Z-axis detector, and are arranged on the front-end circuit board between the front-end circuit board and the host circuit board.

[0011] Furthermore, the gyroscope also includes a temperature sensor assembly, which includes an X-axis temperature sensor, a Y-axis temperature sensor, and a Z-axis temperature sensor, which are respectively used to perform temperature compensation on the corresponding optical fiber rings.

[0012] Further, the X-axis temperature sensor and the Y-axis temperature sensor are respectively mounted on the first side wall and the second side wall of the bracket, and the Z-axis temperature sensor is mounted on the adapter plate.

[0013] Furthermore, the bracket also includes a bottom wall, and the Z-axis shielding ring assembly is installed on the bottom wall in the bracket.

[0014] Furthermore, bosses are arranged at the inner corners of the bracket for accommodating and connecting the adapter plate.

[0015] Furthermore, the bracket is processed with recesses above the bosses for accommodating and connecting the front-end circuit board.

[0016] Further, the bracket is open at the top, and the host circuit board is connected to the bracket at the top surface of the bracket.

[0017] Furthermore, grooves are processed on the first side wall and the second side wall of the bracket, and a plurality of first protrusions and second protrusions are arranged at the bottom of the grooves respectively, and the X-axis shielding ring assembly and the Y-axis shielding ring assembly are respectively installed on the first protrusions and the second protrusions.

[0018] Furthermore, a groove is processed on the third side wall of the bracket, a plurality of third protrusions are arranged at the bottom of the groove, and the light source driving board is mounted on the third protrusions.

[0019] Furthermore, the outer dimensions of the gyroscope are 69.9×67.5×45 mm.

[0020] The advantages of the present invention are:

[0021] 1. The miniaturized three-axis fiber optic gyroscope of the present invention comprises a bracket, three shielding ring components, a 1x3 coupler, a light source driving board, a light source, an adapter board, a 2x2 coupler component, a front-end circuit board, a detector component, and a host circuit board, wherein two shielding ring components are respectively installed on adjacent side walls of the bracket outside the bracket, and another shielding ring component and the adapter board, the 2x2 coupler component, the front-end circuit board, the detector component, and the host circuit board are all installed inside the bracket, and the fiber optic coiling is concentrated on the adapter board, and the 1x3 coupler and the light source driving board and the light source as the heating device are installed outside the bracket on the other side wall of the bracket. Therefore, the present invention adopts an open structure, and the heating device is directly arranged on the outside of the product and is not on the same side wall as the sensitive element, that is, the fiber optic ring, so that the heat generated by the heating device can directly interact with the external environment, reducing the influence of heat on the sensitive element; in addition, the optical path coiling surface is concentrated on the adapter board inside the product, away from the heating component, optimizing the coiling path, reducing the coiling of the optical fiber on other surfaces, and improving the utilization rate of other surfaces, thereby reducing the overall size of the gyroscope.

[0022] 2. In the present invention, the host circuit board is installed at the top of the bracket, which reduces the number of structural parts such as the cover plate, and the overall structure size of the gyroscope is smaller and the weight is lighter.

[0023] 3. The external dimensions of the three-axis fiber optic gyroscope of the present invention can be as small as 69.9×67.5×45 mm, which improves the miniaturization level of the three-axis fiber optic gyroscope. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The above and / or other features and advantages of the present invention will become more easily understood through the following description with reference to the accompanying drawings, which are not drawn to scale and some features are exaggerated or reduced to show details of specific components. In the accompanying drawings:

[0025] Figure 1 It is a three-dimensional exploded view of the miniaturized three-axis fiber optic gyroscope of the present invention;

[0026] Figure 2 The three-dimensional structure of the support in the present invention Figure 1 ;

[0027] Figure 3 The three-dimensional structure of the support in the present invention Figure 2 ;

[0028] Figure 4 is a three-dimensional exploded view of the shielding ring assembly of the present invention;

[0029] Figure 5 It is a stereogram of the transfer in the present invention.

[0030] In the figure: 1- bracket, 101- first side wall, 102- second side wall, 103- third side wall, 104- boss, 105- recess, 106- first protrusion, 107- second protrusion, 108- third protrusion; 2- X-axis shielding ring assembly; 3- Y-axis shielding ring assembly; 4- Z-axis shielding ring assembly, 401- waveguide, 402- optical fiber ring, 403- shielding seat, 404- shielding cover; 5- 1x3 coupler; 6- light source driving board; 7- light source; 8- adapter board, 801- long hole, 802- square hole, 803- Z-axis waveguide outlet, 804- Z-axis optical path outlet; 9- 2x2 coupler assembly; 10- front amplifier circuit board; 11- detector assembly; 12- host circuit board; 13- electrical connector, 14- temperature sensor assembly. DETAILED DESCRIPTION

[0031] The present invention will be described in detail below with reference to the accompanying drawings by means of exemplary embodiments of the present invention. It should be noted that the following detailed description of the present invention is only for the purpose of illustration, and is not intended to limit the present invention.

[0032] The present invention provides a miniaturized three-axis fiber optic gyroscope, which adopts an open structure, distributes the heating device circuit board and the light source directly on the outside of the product, directly interacts with the external environment, and reduces the radiation of the heat generated by them to the sensitive coil. At the same time, miniaturized optical devices are selected to concentrate the optical path mounting surface on the internal adapter board of the product, away from the heating components, optimize the mounting path, and reduce the overall external dimensions of the gyroscope.

[0033] First, the overall reference Figure 1As an exemplary embodiment of the present invention, a miniaturized three-axis fiber optic gyroscope may include a bracket 1 and three shielding ring assemblies, wherein the three shielding ring assemblies are respectively an X-axis shielding ring assembly 2, a Y-axis shielding ring assembly 3 and a Z-axis shielding ring assembly 4, and further includes a 1x3 coupler 5, a light source driving board 6, a light source 7, an adapter board 8, a 2x2 coupler assembly 9, a front-end circuit board 10, a detector assembly 11, a host circuit board 12 and an electrical connector 13, wherein the electrical connector 13 is used to electrically connect the gyroscope to the outside. The bracket 1 is used to install the three shielding ring assemblies, the 1x3 coupler 5, the light source driving board 6, the light source 7, the adapter board 8, the 2x2 coupler assembly 9, the front-end circuit board 10, the detector assembly 11, the host circuit board 12 and the electrical connector 13, wherein the uses of the electronic components are well known in the art and are not described in detail herein.

[0034] Combination Figure 2 and Figure 3 The bracket 1 may be in the shape of a rectangular parallelepiped with an open top, and include a first side wall 101, and a second side wall 102 and a third side wall 103 opposite to each other and adjacent to the first side wall 101. These side walls are used to lay out and install various components in the gyroscope, and the specific structure will be described in detail below.

[0035] like Figure 4 As shown, the three shielding ring components each include a waveguide, a fiber ring, and a shielding seat and a shielding cover made of magnetic material. Taking the Z-axis shielding ring component 4 as an example, it includes a waveguide 401, a fiber ring 402, a shielding seat 403 and a shielding cover 404. The fiber ring is accommodated in the annular cavity between the inner ring and the outer ring of the shielding seat, and can be bonded to the bottom of the cavity by gluing. The waveguide is installed to the inner ring of the shielding seat, and the shielding cover covers the shielding seat to magnetically shield the fiber ring. The shielding cover and the shielding seat can be connected by laser welding, and the shielding seat is provided with a fiber port through which the fiber ring pigtail passes.

[0036] Return to reference Figure 1 , Figure 2 and Figure 3 , three shielding ring components are distributed in three directions of the bracket, the X-axis shielding ring component 2 and the Y-axis shielding ring component 3 are respectively embedded in the first side wall 101 and the second side wall 102 of the bracket 1 through the corresponding shielding seats outside the bracket 1, and the Z-axis shielding ring component 4 is accommodated in the bracket 1. In particular, the first side wall 101 and the second side wall 102 of the bracket 1 are processed with grooves recessed into the inside of the bracket, and the bottom of the grooves are respectively arranged with a plurality of first protrusions 106 and second protrusions 107 extending outward, and the X-axis shielding ring component 2 and the Y-axis shielding ring component 3 are respectively installed on the first protrusion 106 and the second protrusion 107, and the first protrusion 106 and the second protrusion 107 can be processed with threaded holes, and the shielding ring components are installed through the threaded holes.

[0037] The 1x3 coupler 5, the light source driving board 6 and the light source 7 are embedded on the third side wall 103 of the bracket 1 outside the bracket 1. Preferably, a groove recessed toward the inside of the bracket is processed on the third side wall 103 of the bracket 1, and a plurality of third protrusions 108 extending outward are arranged at the bottom of the groove. The light source driving board 6 is mounted on the third protrusions 108. Similarly, the third protrusions 108 may also be processed with threaded holes, and the light source driving board is installed through the threaded holes.

[0038] The adapter plate 8, the front-end circuit board 10 and the host circuit board 12 are sequentially installed in the bracket 1 above the Z-axis shielding ring assembly 4. The electrical connector 13 can be welded on the host circuit board 12. The adapter plate 8 is used for optical fiber coiling, specifically, the optical fiber is routed, welded, and transitioned on the surface of the adapter plate. In this way, the optical path coiling surface can be concentrated on the adapter plate inside the gyroscope and away from the heat-generating components located outside the bracket, realizing the optimization of the coiling path, thereby reducing the coiling of optical fibers on other surfaces, and other surfaces can be equipped with more electronic components, improving the utilization rate of other surfaces, thereby reducing the size of the product.

[0039] Preferably, the bracket 1 further includes a bottom wall (not shown in the figure), and the Z-axis shielding ring assembly 4 is installed on the bottom wall in the bracket 1. Specifically, the inner ring of the shielding ring assembly may be provided with a flange, and the flange is provided with a plurality of through holes, and the shielding ring assembly is connected to the bottom wall of the bracket through the flange. In some embodiments, the bracket 1 is provided with bosses 104 at each internal corner, which are used to place and connect the adapter plate 8. Specifically, the bosses 104 may be provided with threaded holes, and screws may pass through the circular through holes (such as the through holes) at the four corners of the adapter plate. Figure 5 As shown) and through the threaded hole on the boss 104, the adapter plate is installed and fixed. In addition, the bracket 1 is processed with recesses 105 above the boss 104, which are used to place and connect the front-end circuit board 10, and the recesses 105 may be provided with threaded holes through which screws are passed to fix the front-end circuit board. The bracket 1 may be open at the top, and the host circuit board 12 is connected to the bracket 1 at the top surface of the bracket 1, which can be connected by screws. This structure in which the host circuit board is installed at the top of the bracket can reduce the number of structural parts such as the cover plate, making the overall structure of the gyroscope smaller and lighter.

[0040] The 2x2 coupler assembly 9 includes an X-axis 2x2 coupler, a Y-axis 2x2 coupler, and a Z-axis 2x2 coupler, and is arranged on the adapter board 8 between the adapter board 8 and the front-end circuit board 10, and is particularly arranged in parallel on the adapter board 8. Figure 5The 2x2 coupler assembly 9 can be installed in the three long holes 801 on the adapter plate 8. The adapter plate 8 is also provided with a square hole 802 for installing the Z-axis temperature sensor in the temperature sensor assembly 14 to be described below. In addition, the adapter plate 8 is also processed with a Z-axis waveguide outlet 803 and a Z-axis optical path outlet 804. The Z-axis waveguide outlet 803 and the Z-axis optical path outlet 804 can be a conical hole and an arc hole respectively.

[0041] The detector assembly 11 includes an X-axis detector, a Y-axis detector and a Z-axis detector, and is arranged between the front-end circuit board 10 and the host circuit board 12, especially arranged side by side on the front-end circuit board 10. Each detector can be directly fixed to the front-end circuit board 10 by welding.

[0042] In a specific embodiment of the present invention, the gyroscope further includes a temperature sensor assembly 14, which includes an X-axis temperature sensor, a Y-axis temperature sensor, and a Z-axis temperature sensor, which are respectively used to perform temperature compensation on the corresponding optical fiber rings. At high and low temperatures, the heat of the optical fiber rings is uneven, and compensation can be performed according to the output curve and the temperature curve to improve the accuracy. The X-axis temperature sensor and the Y-axis temperature sensor can be installed in the square hole on the first side wall 101 and the square hole on the second side wall 102 of the bracket 1, respectively, and the Z-axis temperature sensor can be installed in the square hole 802 on the adapter plate 8.

[0043] As described above, the present invention adopts an open structure, and the heating device is directly arranged on the outside of the product and is not on the same side wall as the sensitive element, that is, the optical fiber ring, so that the heat generated by the heating device can directly interact with the external environment, reducing the impact of heat on the sensitive element; in addition, the optical path coiling surface is concentrated on the adapter plate inside the product, away from the heating component, optimizing the coiling path, reducing the coiling of optical fiber on other surfaces, and improving the utilization rate of other surfaces, thereby reducing the overall size of the gyroscope. With this structure, the external dimensions of the three-axis fiber optic gyroscope of the present invention can be as small as 69.9×67.5×45mm, improving the miniaturization level of the three-axis fiber optic gyroscope.

[0044] Finally, it should be noted that the features mentioned and / or shown in the above description of the exemplary embodiments of the present invention may be combined in the same or similar manner into one or more other embodiments, combined with the features in other embodiments or substituted for the corresponding features in other implementations. The technical solutions obtained by these combinations or substitutions shall also be deemed to be included in the protection scope of the present invention.

Claims

1. A miniaturized three-axis fiber optic gyroscope, characterized in that: It includes a bracket, three shielding ring assemblies, a 1x3 coupler, a light source driver board, a light source, an adapter board, a 2x2 coupler assembly, a front amplifier circuit board, a detector assembly, a host circuit board and an electrical connector; The bracket is used to install the three shielding ring assemblies, the 1x3 coupler, the light source driving board, the light source, the adapter board, the 2x2 coupler assembly, the front amplifier circuit board, the detector assembly, the host circuit board and the electrical connector. The bracket is in the shape of a rectangular parallelepiped with an open top and includes a first side wall and a second side wall and a third side wall adjacent to the first side wall; The three shielding ring assemblies are respectively an X-axis shielding ring assembly, a Y-axis shielding ring assembly and a Z-axis shielding ring assembly, each comprising a waveguide, an optical fiber ring, and a shielding seat and a shielding cover made of magnetic material, the optical fiber ring is accommodated in an annular cavity between an inner ring and an outer ring of the shielding seat, the waveguide is mounted to the inner ring of the shielding seat, the shielding cover covers the shielding seat to magnetically shield the optical fiber ring, the X-axis shielding ring assembly and the Y-axis shielding ring assembly are respectively embedded on the first side wall and the second side wall of the bracket through the shielding seat outside the bracket, and the Z-axis shielding ring assembly is accommodated in the bracket; The 1x3 coupler, light source driving board and light source are embedded on the third side wall of the bracket outside the bracket; the adapter board, front-end circuit board and host circuit board are installed in the bracket above the Z-axis shielding ring assembly in sequence, the adapter board is used for optical fiber coiling, and the electrical connector is used to electrically connect the gyroscope to the outside; the 2x2 coupler assembly includes an X-axis 2x2 coupler, a Y-axis 2x2 coupler and a Z-axis 2x2 coupler, and are arranged on the adapter board between the adapter board and the front-end circuit board; the detector assembly includes an X-axis detector, a Y-axis detector and a Z-axis detector, and are arranged on the front-end circuit board between the front-end circuit board and the host circuit board.

2. The miniaturized three-axis fiber optic gyroscope according to claim 1, characterized in that: It also includes a temperature sensor assembly, which includes an X-axis temperature sensor, a Y-axis temperature sensor and a Z-axis temperature sensor, which are respectively used to perform temperature compensation on the corresponding optical fiber rings.

3. The miniaturized three-axis fiber optic gyroscope according to claim 2, characterized in that: The X-axis temperature sensor and the Y-axis temperature sensor are respectively mounted on the first side wall and the second side wall of the bracket, and the Z-axis temperature sensor is mounted on the adapter plate.

4. The miniaturized three-axis fiber optic gyroscope according to claim 1 or 2, characterized in that: The bracket also includes a bottom wall, and the Z-axis shielding ring assembly is installed on the bottom wall in the bracket.

5. The miniaturized three-axis fiber optic gyroscope according to claim 1 or 2, characterized in that: The bracket is respectively provided with bosses at the inner corners for accommodating and connecting the adapter plate.

6. The miniaturized three-axis fiber optic gyroscope according to claim 5, characterized in that: The brackets are respectively processed with recesses above the bosses for accommodating and connecting the front-end circuit board.

7. The miniaturized three-axis fiber optic gyroscope according to claim 1 or 2, characterized in that: The bracket is open at the top, and the host circuit board is connected to the bracket at a top surface of the bracket.

8. The miniaturized three-axis fiber optic gyroscope according to claim 1 or 2, characterized in that: The first side wall and the second side wall of the bracket are both processed with grooves, and a plurality of first protrusions and second protrusions are arranged at the bottom of the grooves respectively. The X-axis shielding ring assembly and the Y-axis shielding ring assembly are respectively installed on the first protrusions and the second protrusions.

9. The miniaturized three-axis fiber optic gyroscope according to claim 1 or 2, characterized in that: A groove is processed on the third side wall of the bracket, a plurality of third protrusions are arranged at the bottom of the groove, and the light source driving board is mounted on the third protrusions.

10. The miniaturized three-axis fiber optic gyroscope according to claim 1 or 2, characterized in that: The outer dimensions of the gyroscope are 69.9×67.5×45 mm.

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