A laser gyroscope weight-reducing cavity structure

Abstract

The present invention belongs to the laser gyro technology, and specifically relates to a gyro weight-reducing cavity structure for reducing the jitter of the three-axis coupling of the laser gyro. The cavity includes a cavity, a reflector, an anode, and a cathode. Compared with the traditional non-weight-reducing laser gyro cavity structure, the weight-reducing cavity structure adopts measures such as edge weight reduction, grooving weight reduction on the outer edge of the cavity, enlarging the process hole, and adding weight-reducing process holes to achieve cavity weight reduction; the moment of inertia is reduced. The coupling torque when the gyro is working on the three axes is reduced, thereby reducing the inter-axis coupling of the gyro when the platform is working, and improving the accuracy of the laser gyro working on the platform.

Description

Technical Field

[0001] The invention belongs to laser gyro technology, and in particular relates to a laser gyro weight-reducing cavity structure. Background Art

[0002] For a jitter laser gyro, when working on an IMU, the three-axis gyro will jitter at the same time. The reverse torque generated by each axis gyro when working will act on the platform, causing it to produce periodic vibrations with the same frequency as its own jitter. This vibration acts on the other two-axis gyro, forming coupling interference, affecting the gyro performance, and thus causing the system accuracy to decrease. How to improve the consistency between the three-axis and single-axis operation of a jitter laser gyro is a technical problem that needs to be solved urgently, especially for high-precision jitter laser gyros.

[0003] The traditional solution is to increase the mass of the table design, improve the table stiffness, and reduce the amplitude of the periodic vibration of the table when the gyroscope shakes, thereby reducing the coupling between the gyroscope axes. The disadvantage is that it increases the mass and volume of the table, limiting its application scenarios. Summary of the invention

[0004] The purpose of the present invention is to provide a laser gyroscope weight reduction cavity structure which can effectively reduce the table coupling and improve the gyroscope precision without changing the table structure.

[0005] The technical solution of the present invention is:

[0006] A laser gyro weight-reducing cavity structure, comprising: a cavity 1, four reflectors 2, two anodes 3 and a cathode 4;

[0007] The cavity is a rectangular parallelepiped, and the upper and lower surfaces are square. The cavity has a central large hole perpendicular to the square surface; rectangular annular capillary holes are opened around the central large hole, and the axis connecting the capillary holes is located in the plane of 1 / 2 height of the cavity.

[0008] Four reflectors are arranged at the four corners of the rectangular annular capillary hole;

[0009] A cathode is installed at the center of a rectangular surface of the cavity, and two anodes are symmetrically installed at the centers of two rectangular surfaces perpendicular to it, and the cathode, the anode and the reflector are connected through capillaries;

[0010] A weight-reducing hole 13 and a process hole 12 are provided between the capillary hole 11 and the central large hole 16 of the cavity 1;

[0011] The four rectangular surfaces of the cavity are provided with weight-reducing grooves 14 and edge weight-reducing portions 15 .

[0012] Furthermore, the number of the process holes and the weight-reducing holes are both eight, and the process holes 12 and the weight-reducing holes 13 are evenly distributed around the central large hole 16 and are symmetrical along the central axis of the cathode 4 .

[0013] Furthermore, the diameter of the process hole 12 is larger than the diameter of the weight-reducing hole 13 .

[0014] Furthermore, the weight-reducing groove 14 is located between the central axis of the cathode and / or anode and the reflector, the cross section of the weight-reducing groove is U-shaped, and the weight-reducing groove runs through the upper and lower square surfaces of the cavity.

[0015] Furthermore, four edges of the upper and lower square surfaces of the cavity are respectively chamfered to reduce edge weight; the four chamfered planes are all at an angle of 45° to the square surface;

[0016] The edge weight reduction 15 is symmetrical about the 1 / 2 height plane of the cavity, and the cutting angle width is the same as the depth of the cavity weight reduction groove 14.

[0017] Furthermore, both sides of the weight-reducing groove 14 at the outer edge of the cavity are smooth arc transitions, and the arc radius is greater than or equal to the groove width.

[0018] Furthermore, the cavity in the area where the four corners of the rectangular annular capillary hole are located is provided with a 45° cut angle as a reflector mounting surface;

[0019] The distance between the edge of the weight-reducing groove 14 and the reflector 2 and the cathode and anode mounting surfaces is greater than 3 mm.

[0020] Furthermore, the weight-reducing groove 14 is designed asymmetrically so as to make the center of mass of the laser gyro weight-reducing cavity structure as a whole located on the axis of the central large hole 16 .

[0021] When the jitter laser gyroscope works on three axes simultaneously on the table, the jitter of the gyroscope on any axis will introduce angular vibration errors on the other two axes. The introduced angular vibration errors are related to the weight and moment of inertia of the gyroscope itself and the stiffness and weight of the table. Under the conditions that the angular amplitude of the gyroscope remains unchanged and the stiffness and weight of the table remain unchanged, the greater the weight of the gyroscope itself and the greater the moment of inertia, the greater the angular vibration errors introduced on the other two axes. This solution, under the conditions that the stiffness and weight of the table remain unchanged, reduces the weight of the cavity, reduces the moment of inertia of the gyroscope, and reduces the angular vibration errors introduced by the gyroscope jitter on the other two axes, thereby reducing the coupling of the three axes of the table and improving the test accuracy of the gyroscope on the table.

[0022] After ensuring the installation of the reflector and the electrode, this solution, on the one hand, reduces the weight by adding weight-reducing grooves and edges on the outer edge of the cavity, thereby effectively reducing the gyroscope's moment of inertia while reducing the weight; on the other hand, by increasing the process aperture and adding weight-reducing holes, entities between the capillary pores and the central large hole that have no actual functional requirements are removed, thereby further reducing the cavity weight and moment of inertia.

[0023] The advantages of the present invention are as follows: the present invention combines the moment of inertia and the jitter counter-torque action mechanism, and on the basis of ensuring the function of the resonant cavity, adopts the method of increasing the process holes and adding weight-reducing holes; weight-reducing grooves and edges are added to the capillary pores and the outer edge of the cavity to reduce weight; and the cavity weight is reduced by removing some non-functional materials on the cavity, thereby minimizing the moment of inertia of the cavity, reducing the inter-axis coupling between the three-axis gyroscopes when the table is working, and improving the gyroscope accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a top view schematic diagram of the laser gyro weight reduction cavity structure;

[0025] Figure 2 It is a front view schematic diagram of the laser gyro weight reduction cavity structure;

[0026] Figure 3 This is a schematic diagram of the traditional laser gyro non-weight-reducing cavity structure;

[0027] The figures are marked as follows: 1- cavity, 2- reflector, 3- anode, 4- cathode, 11- capillary hole, 12- process hole, 13- weight reduction hole, 14- weight reduction groove, 15- edge weight reduction, 16- center large hole DETAILED DESCRIPTION

[0028] The present invention is further described in detail below through specific embodiments:

[0029] The laser gyro cavity structure includes a cavity, four reflectors, an anode and a cathode, wherein the four reflectors are arranged in the area where the reflectors are assembled in the cavity, the anode and the cathode are arranged on the cavity between the four reflectors, and the four reflectors and the anode and the cathode are all connected through capillaries in the cavity.

[0030] Conventional laser gyro non-weight-reducing cavity, such as Figure 3 As shown in the figure, the capillary hole is a circle around the ring light path, and the four corners of the capillary hole are equipped with reflectors, the cathode is in the middle, the anode is symmetrically installed on both sides, and there are 8 process holes on the cavity. There is a certain distance between the capillary hole and the outer wall of the cavity. After ensuring the installation of the reflector and the electrode, there is still a large part of the outer edge of the cavity without actual functional requirements; there is a certain distance between the capillary hole and the central large hole. In addition to the 8 process holes, there are too many physical connections, which increase the mass of the cavity and the moment of inertia. When the gyroscope works on the table, the three-axis gyroscope shakes at the same time. The reverse torque generated by each axis gyroscope when working will act on the table, causing it to produce periodic vibrations with the same frequency as its own shaking. This vibration acts on the other two axis gyroscopes, forming coupling interference, affecting the performance of the gyroscope, and thus causing the system accuracy to decrease.

[0031] This paper adopts the laser gyro weight-reducing cavity structure, such as Figure 1As shown, the process hole 12 is enlarged between the capillary 11 and the central large hole 16 of the cavity 1, and the weight reduction hole 13 is added; the weight reduction groove 14 and the edge weight reduction 15 are added between the capillary 11 and the outer edge of the cavity; and the cavity weight reduction is achieved by removing some non-functional materials on the cavity.

[0032] When the gyroscope is working, the shaking axis is the axis of the large hole 16 in the center of the cavity. Since the moment of inertia is proportional to the weight and the square of the distance, the weight reduction grooves 14 and the edge weight reduction 15 on the outer edge of the cavity can significantly reduce the moment of inertia, thereby reducing the vibration error acting on other axial directions when the gyroscope is working. Between the capillary hole 11 and the large center hole 16, the original process hole 12 is enlarged, and the weight reduction hole 13 is added. The process hole 12 and the weight reduction hole 13 are symmetrically distributed around the large center hole 16. The weight reduction grooves 14 on the four outer edges of the cavity adopt an asymmetric design. On the premise of ensuring the assembly of the reflector 2, the anode 3 and the cathode 4, the center of mass of the gyroscope is taken into account to ensure that the center of mass of the gyroscope is located at the axis of the large center hole 16.

[0033] Technical effects:

[0034] The advantage of this weight-reducing cavity structure is that it is different from the method of improving the coupling between the gyro axes by changing the platform structure and increasing the platform weight. The weight-reducing cavity scheme first increases the process hole 12 and adds a weight-reducing hole 13 between the capillary hole 11 and the central large hole 16 of the cavity 1; adds a weight-reducing groove 14 and an edge weight-reducing 15 between the capillary hole 11 and the outer edge of the cavity, removes some non-functional materials on the cavity, and achieves cavity weight reduction and reduces the moment of inertia. When the gyro works on the platform, the reverse torque acting on the platform is reduced, and the periodic vibration error with the same frequency as its own jitter acting on the other two axes of the gyro is reduced, thereby improving the gyro performance. Secondly, the parameters of the process hole 12, the weight-reducing hole 13, the outer edge weight-reducing groove 14 and the edge weight-reducing 15 are determined in combination with the cavity thermal simulation model to ensure that the thermal deformation at the mounting surface and the capillary hole of the four reflectors 2 of the weight-reducing cavity are smaller than the original cavity, and the thermal stability of the cavity is optimized while the cavity is weight-reduced. The actual implementation effect also shows that the weight-reducing cavity structure technology is applied to a certain type of high-precision gyroscope. Under the premise that the platform structure does not change, the three-axis coupling of the platform is further reduced after the weight-reducing cavity is adopted, and the gyroscope accuracy is significantly improved. It has been promoted and applied in a certain model of product.

[0035] The distance between the weight-reducing groove 14 on the outer edge of the cavity and the mounting surface of the reflector 2 is greater than 3 mm.

[0036] The two sides of the weight-reducing groove 14 at the outer edge of the cavity are smooth arc transitions, and the arc radius is greater than or equal to the groove width.

[0037] The outer edge weight reduction groove 14 can be designed asymmetrically to ensure that the overall center of mass of the gyroscope is located on the axis of the central large hole 16 .

[0038] The diameter of the enlarged process hole 12 is larger than the diameter of the newly added weight-reducing hole 13 .

[0039] The cavity edge weight reduction 15 is a symmetrical structure, and its width is the same as that of the cavity weight reduction groove 14 .

Claims

1. A laser gyro weight-reducing cavity structure, characterized in that The structure comprises: a cavity (1), four reflectors (2), two anodes (3) and a cathode (4); The cavity is a rectangular parallelepiped, and the upper and lower surfaces are square. The cavity has a central large hole perpendicular to the square surface; rectangular annular capillary holes are opened around the central large hole, and the axis connecting the capillary holes is located in the plane of 1 / 2 height of the cavity. Four reflectors are arranged at the four corners of the rectangular annular capillary hole; A cathode is installed at the center of a rectangular surface of the cavity, and two anodes are symmetrically installed at the centers of two rectangular surfaces perpendicular to it, and the cathode, the anode and the reflector are connected through capillaries; A weight-reducing hole (13) and a process hole (12) are provided between the capillary hole (11) and the central large hole (16) of the cavity (1); the number of the process holes and the weight-reducing hole is eight, and the process holes (12) and the weight-reducing holes (13) are evenly distributed around the central large hole (16) and symmetrical along the central axis of the cathode (4); the diameter of the process hole (12) is larger than the diameter of the weight-reducing hole (13); Four rectangular surfaces of the cavity are provided with weight-reducing grooves (14) and edge weight-reducing grooves (15).

2. The laser gyro weight reduction cavity structure according to claim 1, characterized in that: The weight-reducing groove (14) is located between the central axis of the cathode and / or the anode and the reflector, the cross section of the weight-reducing groove is U-shaped, and the weight-reducing groove runs through the upper and lower square surfaces of the cavity.

3. The laser gyro weight reduction cavity structure according to claim 2, characterized in that: The four edges of the upper and lower square surfaces of the cavity are respectively chamfered to reduce edge weight; the four chamfered planes are all at an angle of 45° to the square surface; The edge weight reduction (15) is symmetrical about a plane having a height of 1 / 2 of the cavity, and the cutting angle width is the same as the depth of the cavity weight reduction groove (14).

4. The laser gyro weight reduction cavity structure according to claim 2, characterized in that: Both sides of the weight-reducing groove (14) at the outer edge of the cavity are smooth arc transitions, and the arc radius is greater than or equal to the groove width.

5. The laser gyro weight reduction cavity structure according to claim 1, characterized in that: The cavity in the area where the four corners of the rectangular annular capillary hole are located is provided with a 45° cut angle as a reflector mounting surface; The distance between the edge of the weight-reducing groove (14) and the reflector (2) and the cathode and anode mounting surfaces is greater than 3 mm.

6. The laser gyro weight reduction cavity structure according to claim 1, characterized in that: The weight-reducing groove (14) adopts an asymmetric design, so as to make the overall center of mass of the laser gyro weight-reducing cavity structure be located on the axis of the central large hole (16).

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