Self-locking laser cavity sealing structure

Abstract

A self-locking type laser cavity sealing structure comprises a sealing cover plate, a sealing shell and a screw, the sealing cover plate is designed with a self-locking sealing tenon and a main sealing tenon, the sealing shell is designed with a self-locking sealing groove and a main sealing groove, a self-locking filling space between the self-locking sealing tenon and the self-locking sealing groove is filled by a self-locking sealing ring, a main filling space between the main sealing tenon and the main sealing groove is filled by a main sealing ring, the volume of the self-locking sealing ring is 1.05-1.2 times the volume of the self-locking filling space, and the volume of the main sealing ring is 1.05-1.2 times the volume of the main filling space.The present application utilizes the pressure difference between the inside and outside of the laser cavity caused by the on-orbit vacuum environment of the laser cavity to further compress the sealing ring, realizes the self-locking function of the sealing, avoids the on-orbit leakage of the laser cavity during emission, and improves the sealing reliability of the on-orbit laser cavity.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of space optical remote sensors, and relates to a sealing structure of a spaceborne laser. BACKGROUND

[0002] The sealing structure can prevent external pollutants from entering the laser cavity, effectively improves the service life of devices in the spaceborne laser cavity, and has a wide application in spaceborne lasers.

[0003] The spaceborne laser is used in a vacuum environment, and pure air or nitrogen with a pressure of 0.12 MPa is generally filled in the cavity during ground debugging. Considering the damage of low-pressure release of devices in orbit to the laser, the leakage rate of the laser cavity is required to be relatively high. According to the design life of the laser, the overall leakage rate of the laser cavity is required to be less than or equal to 1*10 -6 Pa·m 3 / s, and the leakage rate of a single point of the local part is required to be less than or equal to 1*10 -7 Pa·m 3 / s. The traditional sealing structure is mostly sealed by a rubber ring, the rubber ring is a non-metal material, and volatile pollutants can pollute the laser cavity. In addition, the laser cavity has a relatively high leakage rate, and the mechanical conditions during the launch of the spacecraft are relatively severe, so the reliability of the sealing needs to be further improved. SUMMARY

[0004] The application solves the technical problem of overcoming the deficiencies of the prior art and providing a self-locking spaceborne laser cavity sealing structure. The pressure difference between the inside and outside of the laser cavity caused by the vacuum environment of the laser cavity in orbit further compresses the sealing ring, realizes the self-locking function of sealing, avoids the leakage of the laser cavity during launch in orbit, and improves the sealing reliability of the spaceborne laser cavity.

[0005] The technical solution of the application is as follows:

[0006] A self-locking laser cavity sealing structure comprises a sealing cover plate, a sealing shell and a screw, the sealing cover plate is arranged at the cavity position of the sealing shell through the screw cover; the sealing cover plate is designed with a self-locking sealing tenon and a main sealing tenon, the sealing shell is designed with a self-locking sealing groove and a main sealing groove, the self-locking sealing tenon is inserted into the self-locking sealing groove, the main sealing tenon is inserted into the main sealing groove, a self-locking filling space between the self-locking sealing tenon and the self-locking sealing groove is filled by a self-locking sealing ring, and a main filling space between the main sealing tenon and the main sealing groove is filled by a main sealing ring.

[0007] The volume of the self-locking sealing ring is 1.05-1.2 times the volume of the self-locking filling space, and the volume of the main sealing ring is 1.05-1.2 times the volume of the main filling space.

[0008] The self-locking sealing ring is located on the inner side of the self-locking sealing tenon.

[0009] The outer side of the self-locking sealing groove is perpendicular to the cover plate, the inner side of the self-locking sealing groove is arranged in an inclined manner, and the self-locking sealing groove gradually approaches the middle part of the sealed shell along the direction close to the cover plate; the outer side of the self-locking sealing tongue is perpendicular to the cover plate, and the inner side of the self-locking sealing tongue is arranged in an inclined manner and has the same inclined direction as the inner side of the self-locking sealing groove.

[0010] The main sealing ring is located between the end of the main sealing tongue and the bottom of the main sealing groove.

[0011] The main sealing groove connects two indium storage grooves, the two indium storage grooves are located on one side of the main sealing groove facing the middle part of the sealed shell and the other side of the main sealing groove away from the middle part of the sealed shell, and the two indium storage grooves are located at the end of the main sealing groove close to the cover plate; the depth of the indium storage groove along the direction perpendicular to the cover plate is less than the depth of the main sealing tongue along the direction perpendicular to the cover plate.

[0012] The sum of the volumes of the two indium storage grooves is not less than the difference between the volume of the main sealing ring and the volume of the main filling space.

[0013] The material of the main sealing ring is metal indium, and the material of the self-locking sealing ring is fluorine rubber.

[0014] The materials of the sealing cover plate and the sealing shell are the same metal material.

[0015] The screws connect the sealing cover plate and the sealing shell, and the distance between adjacent screws is not greater than 20 mm.

[0016] In summary, the present application at least includes the following beneficial technical effects:

[0017] The present application adopts a double-layer self-locking sealing design, the sealing space formed by the inner sealing groove and the sealing tongue has a main sealing effect on the laser cavity, the sealing ring is made of metal indium material, which prevents external pollutants from entering the laser cavity and also prevents the pollutants volatilized from the outer self-locking sealing ring from entering the transmitter cavity. The sealing space formed by the inner sealing groove and the sealing tongue realizes the on-orbit self-locking sealing characteristic of the laser cavity, prevents micro-leakage of the laser cavity, and improves the on-orbit leakage rate of the laser cavity. Through test verification, the single-point sealing leakage rate of the scheme under vacuum condition is required to be ≤2*10 -8 Pa·m 3 / s. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 The present application is only a schematic self-locking sealing principle diagram of the annular self-locking sealing tongue;

[0019] Figure 2 The present application is a transmitter cavity perspective view;

[0020] Figure 3The schematic diagram of the annular sealing ring of the application;

[0021] Figure 4 The cross-sectional view of the laser cavity sealing structure of the application;

[0022] Figure 5 The enlarged view of the main sealing structure of the application.

[0023] Marked as: 1, sealing cover plate; 2, sealing shell; 3, self-locking filling space; 4, main filling space; 5, through screw; 11, self-locking sealing tenon; 12, main sealing tenon; 21, self-locking sealing groove; 22, main sealing groove; 31, self-locking sealing ring; 41, main sealing ring; 42, indium storage groove. DETAILED DESCRIPTION

[0024] As Figure 2 shown, the sealing structure of the satellite-borne laser mainly includes a sealing cover plate 1 and a sealing shell 2, which are connected through screws 5, and the screws 5 are uniformly arranged with a spacing of 20 mm. The sealing cover plate 1 and the sealing shell 2 jointly construct a laser sealing cavity.

[0025] As Figure 3 shown, the sealing cover plate 1 is designed with an annular self-locking sealing tenon 11 and a main sealing tenon 12, and the sealing shell 2 is designed with an annular self-locking sealing groove 21 and a main sealing groove 22. Among them, the self-locking sealing tenon 11 and the self-locking sealing groove 21 are designed on the outside, and the main sealing tenon 12 and the main sealing groove 22 are designed on the inside.

[0026] As Figure 4 shown, after the sealing cover plate 1 and the sealing shell 2 are assembled, the self-locking sealing tenon 11 is inserted into the self-locking sealing groove 21 to form a self-locking filling space 3, and the main sealing tenon 12 is inserted into the main sealing groove 22 to form a main filling space 4, which is the space from the bottom of the main sealing tenon 12 to the bottom of the main sealing groove 22. The self-locking filling space 3 is filled with a self-locking sealing ring 31, and the main filling space 4 is filled with a main sealing ring 41. The cross-sectional shape of the main sealing ring 41 is circular, and the cross-sectional shape of the self-locking sealing ring 31 is rectangular. The main sealing ring 41 is located on the lower side of the main sealing tenon 12, and the self-locking sealing ring 31 is located on the inner side of the self-locking sealing tenon 11. The volume of the self-locking sealing ring 31 is between 1.05 and 1.2 times the volume of the self-locking filling space 3, and the volume of the main sealing ring 41 is between 1.05 and 1.2 times the volume of the main filling space 4.

[0027] The above-mentioned sealing shell and sealing cover plate jointly constitute a laser sealing cavity, and through the two annular sealing grooves on the sealing shell and the two annular sealing tenons on the sealing cover plate, a filling space is jointly constructed. The outer filling space is filled with a fluororubber sealing ring, and the inner filling space is filled with a metal indium sealing ring. The outer sealing space realizes in-orbit self-locking sealing, and the self-locking sealing principle is as follows Figure 1As shown, under the track environment condition, the laser cavity is in vacuum environment, and the pressure difference P between the inside and outside of the cavity causes the sealing cover plate to deform, which leads to the movement of the self-locking sealing tongue along the A direction, further reduces the sealing space, compresses the sealing ring, and improves the sealing reliability.

[0028] The outer side of the self-locking sealing groove 21 is perpendicular to the sealing cover plate 1, and the inner side of the self-locking sealing groove 21 is inclined and gradually approaches the middle part of the sealing shell 2 along the direction close to the sealing cover plate 1. Similarly, the outer side of the self-locking sealing tongue 11 is perpendicular to the sealing cover plate 1, and the inner side of the self-locking sealing tongue 11 is inclined and the inclination direction is consistent with the inclination direction of the inner side of the self-locking sealing groove 21. Through this setting, the sealing effect between the self-locking sealing tongue 11 and the self-locking sealing groove 21 is improved.

[0029] As shown in the figure, Figure 5 Two indium storage grooves 42 are arranged at the upper end of the main filling space 4. Specifically, one indium storage groove 42 is located on the side of the main sealing groove 22 facing the middle part of the sealing shell 2, and the other indium storage groove 42 is located on the side of the main sealing groove 22 away from the middle part of the sealing shell 2, and the two indium storage grooves 42 are located at the end of the main sealing groove 22 close to the sealing cover plate 1. The sum of the volumes of the two indium storage grooves 42 is not less than the difference between the volume of the main sealing ring 41 and the volume of the main filling space 4. The depth of the indium storage groove 42 along the direction perpendicular to the sealing cover plate 1 is less than the depth of the main sealing tongue 12 along the direction perpendicular to the sealing cover plate 1. When the main sealing ring 41 is extruded, the main sealing ring 41 is deformed and fills the main filling space 4, and the excess material flows into the indium storage groove 42 through the gap between the two sides of the main sealing tongue 12 and the inner wall of the main sealing groove 22.

[0030] In this embodiment, the self-locking sealing ring 31 is made of fluororubber material with a Shore hardness greater than 50HA, the main sealing ring 41 is made of metal indium, and the sealing cover plate 1 and the sealing shell 2 are made of titanium alloy material.

[0031] Assembly method: first, clean the sealing cover plate 1 and the sealing shell 2, focus on cleaning the sealing tenon and the sealing groove part. After evenly coating the self-locking sealing ring 31 with sealing grease, put it into the self-locking sealing groove 21, evenly put the main sealing ring 41 into the main sealing groove 22, adjust the gap between the main sealing ring 41 and the two groove walls of the main sealing groove 22 by using a plug gauge, and try to ensure that the main sealing ring 41 is placed in the center of the main sealing groove 22. Install the sealing cover plate 1, so that the self-locking sealing tenon 11 is aligned with the self-locking sealing groove 21, and the main sealing tenon 12 is aligned with the main sealing groove 22. Tighten the screws 5 alternately along the diagonal direction, ensure that the self-locking sealing ring 31 and the main sealing ring 41 are uniformly stressed and compressed, and in the process of tightening the screws 5, the edge gap between the sealing cover plate 1 and the sealing shell 2 can be measured by using a plug gauge of different thicknesses to ensure that the self-locking sealing ring 31 and the main sealing ring 41 are uniformly stressed. After there is no gap between the edge of the sealing cover plate 1 and the sealing shell 2, use a torque wrench to apply torque to the screws 5, and the size of the applied torque is determined according to the size of the selected screws 5. In this embodiment, M4 inner hexagonal cylindrical head screws are selected, and the tightening torque is 1.5 N·M.

[0032] The contents not described in detail in the specification of the present application are known to those skilled in the art.

[0033] Although the present application is disclosed with the preferred embodiments as above, it is not intended to limit the present application, and any person skilled in the art can make possible changes and modifications without departing from the spirit and scope of the present application. Therefore, the protection scope of the present application should be determined by the scope defined in the claims of the present application.

Claims

1. A self-clamping laser cavity seal structure, characterized by: It comprises a sealing cover plate (1), a sealing shell (2) and screws, the sealing cover plate (1) is arranged on the cavity position of the sealing shell (2) by the screws (5); The sealing cover plate (1) is designed with a self-locking sealing tongue (11) and a main sealing tongue (12), the self-locking sealing tongue (11) is located outside the main sealing tongue (12), the sealing shell (2) is designed with a self-locking sealing groove (21) and a main sealing groove (22), the self-locking sealing tongue (11) is inserted into the self-locking sealing groove (21), the main sealing tongue (12) is inserted into the main sealing groove (22), a self-locking filling space (3) is reserved between the self-locking sealing tongue (11) and the self-locking sealing groove (21) and filled by a self-locking sealing ring (31), a main filling space (4) is reserved between the main sealing tongue (12) and the main sealing groove (22) and filled by a main sealing ring (41); the material of the main sealing ring (41) is metal indium; The main sealing groove (22) is connected with two indium storage grooves (42), the two indium storage grooves (42) are respectively located on one side of the main sealing groove (22) facing the middle part of the sealing shell (2) and the other side of the main sealing groove (22) away from the middle part of the sealing shell (2), and the two indium storage grooves (42) are located at the end of the main sealing groove (22) close to the sealing cover plate (1); the depth of the indium storage groove (42) along the direction perpendicular to the sealing cover plate (1) is less than the depth of the main sealing tongue (12) along the direction perpendicular to the sealing cover plate (1); The self-locking sealing ring (31) is located inside the self-locking sealing tongue (11); The outer side surface of the self-locking sealing groove (21) is perpendicular to the sealing cover plate (1), the inner side surface of the self-locking sealing groove (21) is arranged to be inclined and gradually close to the middle part of the sealing shell (2) along the direction close to the sealing cover plate (1), the outer side surface of the self-locking sealing tongue (11) is perpendicular to the sealing cover plate (1), and the inner side surface of the self-locking sealing tongue (11) is arranged to be inclined and the inclination direction is consistent with the inclination direction of the inner side surface of the self-locking sealing groove (21).

2. The self-clamping laser cavity seal structure of claim 1, wherein: The volume of the self-locking sealing ring (31) is 1.05-1.2 times the volume of the self-locking filling space (3), and the volume of the main sealing ring (41) is 1.05-1.2 times the volume of the main filling space (4).

3. The self-clamping laser cavity seal structure of claim 1, wherein: The main sealing ring (41) is located between the end of the main sealing tongue (12) and the bottom of the main sealing groove (22).

4. The self-clamping laser cavity seal structure of claim 3, wherein: The sum of the volumes of the two indium storage grooves (42) is not less than the difference between the volume of the main sealing ring (41) and the volume of the main filling space (4).

5. The self-clamping laser cavity seal structure of claim 1, wherein: The material of the self-locking sealing ring (31) is fluorine rubber.

6. The self-clamping laser cavity seal structure of claim 1, wherein: The screws connect the sealing cover plate (1) and the sealing shell (2), and the distance between the screws is not greater than 20 mm.

7. The self-clamping laser cavity seal structure of claim 1, wherein, The assembly method among the sealing cover plate (1), the sealing shell (2) and the screws comprises: S1: the self-locking sealing ring (31) is uniformly coated with sealing grease and then put into the self-locking sealing groove (21), the main sealing ring (41) is uniformly put into the main sealing groove (22), the gap between the main sealing ring (41) and the two groove walls of the main sealing groove (22) is adjusted by using a plug gauge, and the main sealing ring (41) is placed in the center of the main sealing groove (22) as much as possible; S2: install the sealing cover plate (1), make the self-locking sealing tenon (11) align the self-locking sealing groove (21) insert, the main sealing tenon (12) align the main sealing groove (22) insert, along the diagonal direction alternately tighten the screw, so that the self-locking sealing ring (31) and the main sealing ring (41) are uniformly stressed and compressed; S3: until the sealing cover plate (1) and the sealing shell (2) have no gap between the edges, use a torque wrench to apply torque to the screw.

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