Sealing structure of in-line ignition control circuit box

Abstract

The invention discloses an in-line ignition control circuit box sealing structure. The circuit box sealing structure comprises a box body (10), a box cover (20), a sunk screw (30), a sealing cover (40) and high-temperature-resistant epoxy glue. A plurality of mounting threaded holes (11) are formed in the box body (10) at certain intervals in the circumferential direction, and a circle of sealing boss structure (12) is arranged on the end face where the mounting threaded holes (11) are located; the box cover (20) is provided with a mounting through hole (21) and a sealing groove structure (22) which correspond to the box body (10); and the sealing cover (40) covers the butt joint parts of the countersunk head screw (30), the box cover (20) and the box body (10). According to the circuit box sealing structure, reliable sealing of the circuit box is achieved, the layering problem of the insulating glue layer is avoided, it is ensured that the circuit box normally works under the high-altitude low-air-pressure condition, the structural strength of the circuit box is improved, and the circuit box sealing structure is easy to assemble, low in cost and convenient to inspect.

Description

Technical Field

[0001] The invention belongs to the technical field of solid rocket engine structures, and in particular relates to an in-line ignition control circuit box sealing structure. Background Art

[0002] In recent years, the increasingly complex battlefield electromagnetic environment and storage environment have put forward higher requirements on the capabilities of weapons and equipment. As the core component of solid rocket engines, the reliability of the ignition system in actual combat has received more and more attention. Since the in-line ignition system is currently the safest and most reliable ignition system that can withstand harsh electromagnetic environments and high impact overload mechanical environments, it has been gradually promoted and used in tactical solid rocket engines.

[0003] The in-line safety ignition control system is mainly composed of an ignition control circuit, an electrical connector, and an impact piece ignition tube. The system releases the safety fuse within a specified time through the ignition control circuit to generate a high-energy current of kilovolts / kiloamperes to detonate the impact piece ignition tube, and then ignites the igniter charge and the engine charge in turn to ignite the engine. Since the ignition control circuit is relatively complex, it is usually designed as an independent component and installed in an appropriate position according to the spatial layout. This article refers to this independent component as an in-line ignition control circuit box (hereinafter referred to as the circuit box).

[0004] For air-to-air missiles, the launch altitude of their carrier aircraft is generally between 0km and 21km. According to Article 3.9.4 of GJB356A-2005, air-to-air missiles should work normally under the following conditions: a) Air pressure: the atmospheric pressure at the highest point of the missile's operating altitude; b) Temperature: -45°C. After the fuse is released, the internal high-voltage capacitor of the circuit box needs to be quickly charged to about 2 kilovolts and ensure that it does not release pressure before receiving the ignition command. However, under high-altitude and low-pressure conditions, if the internal insulation of the circuit box is not in place, high-voltage creepage will occur during the boost process, causing circuit damage. In the current conventional design, the insulation under low-pressure conditions is mainly guaranteed by the insulating glue layer of the circuit board, and the tightness of the insulating glue layer and the circuit board plays a decisive role in the insulation of the product.

[0005] However, the circuit box has a complex internal structure and many components, which requires a very high potting process for the insulating glue layer. Often, the insulating glue layer is not potted in place, resulting in the product failing to work properly due to the delamination of the insulating glue layer and the circuit board under high altitude and low pressure conditions. According to this failure mode, through experiments and research, engineers and technicians believe that when the sealing of the circuit box meets the use requirements under low pressure conditions, the delamination of the insulating glue layer caused by the pressure difference between the inside and outside of the circuit box can be avoided. Traditional sealing structures usually use sealing rings for sealing. The use of sealing rings needs to consider the heat transfer effect during the operation of the engine, and the circuit box often fails to seal due to structural stress during the operation of the engine. Therefore, multiple sealing rings are required to ensure reliable operation. However, when using multiple sealing rings, complex designs such as internal exhaust are required, and the processing and manufacturing costs are high, and the assembly and inspection are complicated. Therefore, how to easily achieve reliable sealing of the circuit box to ensure the insulation and normal operation of the circuit box is a problem that needs to be solved at present. Summary of the invention

[0006] In order to solve the above problems, the purpose of the present invention is to provide an in-line ignition control circuit box sealing structure, which not only seals the inside of the circuit box, avoids the problem of stratification of the insulating rubber layer of the circuit box, ensures the normal operation of the circuit box under high altitude and low pressure conditions, but also improves the structural strength of the circuit box, and is simple to assemble, low cost, and easy to inspect.

[0007] The specific technical solutions of the present invention are as follows:

[0008] An in-line ignition control circuit box sealing structure, characterized in that the circuit box sealing structure comprises: a box body, a box cover, countersunk screws, a sealing cover, and high temperature resistant epoxy glue;

[0009] The box body is provided with a plurality of mounting threaded holes at a certain interval along the circumferential direction, and a circle of sealing boss structures is provided on the end surface where the mounting threaded holes are located;

[0010] The box cover is provided with a mounting through hole corresponding to the mounting threaded hole of the box body and a sealing groove structure corresponding to the sealing boss structure of the box body;

[0011] The sealing cover is integrally matched with the outer surface of the box cover and covers the countersunk screws, the butt joint between the box cover and the box body.

[0012] Furthermore, the box body and the box cover are connected and locked by the countersunk screws, and the sealing boss structure and the sealing groove structure are matched and sealed to form a first sealing structure of the circuit box and constitute the circuit box body.

[0013] Furthermore, the sealing cover is bonded to the circuit box body by using the high temperature resistant epoxy adhesive to form a second sealing structure of the circuit box, and a final circuit box is obtained at the same time.

[0014] Preferably, a control circuit board is installed inside the box body and the whole machine is potted with potting glue.

[0015] Preferably, the potting glue is applied in the sealing groove structure of the box cover.

[0016] Preferably, the sealing boss structure of the box body is arranged on the inner side of the mounting threaded hole.

[0017] Preferably, after the sealing cover is bonded to the circuit box body, pressure is applied to the sealing cover to extrude, exhaust and solidify the high temperature resistant epoxy adhesive.

[0018] Preferably, the sealing cover is a basket-type flange structure.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] (1) The in-line ignition control circuit box sealing structure provided by the present invention realizes reliable sealing of the circuit box, avoids the problem of delamination of the insulating rubber layer of the circuit box, ensures the normal operation of the circuit box under high altitude and low air pressure conditions, and has the advantages of low cost, simple assembly, easy inspection, and strong feasibility.

[0021] (2) Compared with the conventional sealing ring sealing structure, the sealing cover adopted by the present invention effectively improves the structural strength of the circuit box, which not only enhances the environmental adaptability of the circuit box, but also effectively avoids the aging problem of the sealing ring after long-term storage, thereby improving the storage reliability of the product.

[0022] (3) The sealing structure of the in-line ignition control circuit box provided by the present invention is flexible, and different structural schemes are derived according to the requirements of different circuit box structures, thereby meeting the sealing requirements of various circuit boxes and having universal applicability. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions disclosed in the present invention, the following briefly introduces the drawings required to be used in some embodiments disclosed in the present invention. Obviously, the drawings described below are only drawings of some embodiments disclosed in the present invention. For ordinary technicians in this field, other drawings can also be obtained based on these drawings. In addition, the drawings described below can be regarded as schematic diagrams, and are not limitations on the actual size of the products involved in the embodiments disclosed in the present invention, the actual process of the method, etc.

[0024] Figure 1 An overall top view of the circuit box sealing structure provided by an embodiment of the present invention;

[0025] Figure 2 An exploded view of a circuit box sealing structure provided by an embodiment of the present invention;

[0026] Figure 3 A schematic diagram of a box body structure of a circuit box sealing structure provided by an embodiment of the present invention;

[0027] Figure 4 A schematic diagram of a box cover structure of a circuit box sealing structure provided by an embodiment of the present invention;

[0028] Figure 5 A schematic structural diagram of a circuit box body of a circuit box sealing structure provided by an embodiment of the present invention.

[0029] The accompanying drawings are marked as follows:

[0030] 10. Box body; 11. Mounting threaded hole; 12. Sealing boss structure; 20. Box cover; 21. Mounting through hole; 22. Sealing groove structure; 30. Countersunk screw; 40. Sealing cover. DETAILED DESCRIPTION

[0031] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0032] The present invention provides an in-line ignition control circuit box sealing structure, characterized in that the circuit box sealing structure comprises: a box body, a box cover, countersunk screws, a sealing cover, and high temperature resistant epoxy glue;

[0033] The box body is provided with a plurality of mounting threaded holes at a certain interval along the circumferential direction, and a circle of sealing boss structures is provided on the end surface where the mounting threaded holes are located;

[0034] The box cover is provided with a mounting through hole corresponding to the mounting threaded hole of the box body and a sealing groove structure corresponding to the sealing boss structure of the box body;

[0035] The sealing cover is integrally matched with the outer surface of the box cover and covers the countersunk screws, the butt joint between the box cover and the box body.

[0036] Furthermore, the box body and the box cover are connected and locked by the countersunk screws, and the sealing boss structure and the sealing groove structure are matched and sealed to form a first sealing structure of the circuit box, and the circuit box body is obtained at the same time.

[0037] Furthermore, the sealing cover is bonded to the circuit box body by using the high temperature resistant epoxy adhesive to form a second sealing structure of the circuit box, and a final circuit box is obtained at the same time.

[0038] Preferably, a control circuit board is installed inside the box body and the whole machine is potted with potting glue;

[0039] Preferably, a proper amount of the potting glue is applied in the sealing groove structure of the box cover.

[0040] Preferably, the sealing boss structure of the box body is arranged on the inner side of the mounting threaded hole.

[0041] Preferably, after the sealing cover is bonded to the circuit box body, appropriate pressure is applied to the sealing cover to perform extrusion, exhaust and curing of the high temperature resistant epoxy adhesive.

[0042] Preferably, the sealing cover is a basket-type flange structure.

[0043] Example 1

[0044] This embodiment provides an in-line ignition control circuit box sealing structure, such as Figure 1 , Figure 2 As shown, the circuit box sealing structure comprises: a box body (10), a box cover (20), a countersunk screw (30), and a sealing cover (40); the box body (10), the box cover (20), and the sealing cover (40) are all made of aluminum alloy material, with the surface treated with Et·A(S)Cs, and the countersunk screw (30) is a stainless steel M2.5 standard screw; the circuit box sealing structure is designed as a 200° open fan-shaped structure according to the internal control circuit layout requirements, and a circuit box installation connection part and an electrical connector interface are arranged outside the box body (10) according to the installation and interface requirements, and the outer diameter of the circuit box sealing structure is The inner diameter is The thickness is 37mm.

[0045] The box body (10) is provided with 11 M2.5 mounting threaded holes (11) at a certain interval along the circumferential direction on its upper end surface according to the circuit box profile requirements, and a sealing boss structure (12) with a height of 2 mm and a width of 1 mm is provided in the inner circle of the mounting threaded holes (11). Figure 3 shown.

[0046] The box cover (20) is provided with a screw mounting through hole (21) corresponding to the mounting threaded hole (11) of the box body (10) and a sealing groove structure (22) with a circumferential width of 1.4 mm corresponding to the sealing boss structure (12) of the box body (10), so as to ensure that the box body (10) and the box cover (20) are tightly matched. The thickness of the box cover (20) is 5 mm. Figure 4 shown.

[0047] The sealing cover (40) adopts a basket-type flange structure design, which is integrally matched with the outer surface of the box cover (20), with a flange gap of 0.2 mm, a flange width of 15 mm, and a uniform thickness of 1.2 mm; a basket-type through hole is arranged on the fan-shaped assembly surface of the sealing cover (40), two through holes with a diameter of 20 mm are symmetrically arranged at a position with an angle of 12° to the flange edge, and 13 basket-type through holes with a diameter of 10 mm are arranged between the two through holes at an interval of 22°. The hollow structure design is mainly used for the subsequent extrusion and exhaust of the high-temperature resistant epoxy glue to ensure effective bonding, such as Figure 1 , Figure 2 shown.

[0048] The circuit box sealing structure specifically includes: a control circuit board is installed in the internal space of the box body (10) and is potted as a whole with a flexible potting glue (the control circuit board and the installation structure are simple, they do not belong to the content of the present invention and are not shown in the figure). An appropriate amount of flexible potting glue is applied to the sealing groove structure (22) of the box cover (20), and the box body (10) and the box cover (20) that have been potted as a whole are locked by countersunk screws (30). At the same time, the sealing boss structure (12) and the sealing groove structure (22) are matched and sealed to form the first sealing structure of the circuit box, and at the same time, the circuit box body is obtained, such as Figure 5 shown.

[0049] Furthermore, after the flexible potting glue in the circuit box body is cured, the sealing cover (40) is bonded to the circuit box body using a high temperature resistant epoxy glue, and appropriate pressure is applied to the bonded sealing cover (40) to extrude, exhaust and cure the high temperature resistant epoxy glue to form a second sealing structure of the circuit box, and at the same time, a final circuit box is obtained, such as Figure 1 shown.

[0050] Many products adopting the technical solutions provided in the embodiments of the present invention have passed the 0km-21km low-pressure test verification and flight test assessment, and the product performance is stable and the feasibility is strong.

[0051] Although the present invention has been disclosed as a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art can make possible changes and modifications to the technical solution of the present invention by using the above disclosed content without departing from the spirit and scope of the present invention. Therefore, any simple modification, equivalent change and modification made to the above embodiment according to the technical essence of the present invention without departing from the content of the technical solution of the present invention shall belong to the protection scope of the technical solution of the present invention. The protection scope of the present invention shall be subject to the attached claims.

Claims

1. An in-line ignition control circuit box sealing structure, characterized in that: The circuit box sealing structure comprises: a box body (10), a box cover (20), countersunk screws (30), a sealing cover (40), and high temperature resistant epoxy glue; The box body (10) is provided with a plurality of mounting threaded holes (11) at a certain interval along the circumferential direction, and a circle of sealing boss structures (12) is provided on the end surface where the mounting threaded holes (11) are located; The box cover (20) is provided with a mounting through hole (21) corresponding to the mounting threaded hole (11), and the box cover (20) is also provided with a sealing groove structure (22) corresponding to the sealing boss structure (12); The sealing cover (40) is integrally matched with the outer surface of the box cover (20), and covers the countersunk screw (30), the butt joint between the box cover (20) and the box body (10).

2. The in-line ignition control circuit box sealing structure according to claim 1, characterized in that: The box body (10) and the box cover (20) are connected and locked by the countersunk screws (30), and the sealing boss structure (12) and the sealing groove structure (22) are matched and sealed to form the first sealing structure of the circuit box and the circuit box body.

3. The in-line ignition control circuit box sealing structure according to claim 1, characterized in that: The sealing cover (40) is bonded to the circuit box body by using the high temperature resistant epoxy adhesive to form a second sealing structure of the circuit box and a final circuit box.

4. The in-line ignition control circuit box sealing structure according to claim 1 or 2, characterized in that: A control circuit board is installed inside the box body (10) and potting glue is used to pot the entire machine.

5. The circuit box sealing structure according to claim 1 or 2, characterized in that: The sealing glue is smeared inside the sealing groove structure (22) of the box cover (20).

6. The in-line ignition control circuit box sealing structure according to claim 1 or 2, characterized in that: The sealing boss structure (12) of the box body (10) is arranged on the inner side of the mounting threaded hole (11).

7. The in-line ignition control circuit box sealing structure according to claim 1 or 3, characterized in that: After the sealing cover (40) is bonded to the circuit box body, pressure is applied to the sealing cover (40) to perform extrusion, exhaust and curing of the high temperature resistant epoxy adhesive.

8. The in-line ignition control circuit box sealing structure according to claim 1 or 3, characterized in that: The sealing cover (40) is a basket-type flange structure.

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