A pyrotechnic fuse

Abstract

The utility model relates to a fuse, concretely relates to a smoke and fire type fuse, including the casing, the top of casing is equipped with the igniter, the middle part of casing is equipped with the conductor, and the both ends of conductor respectively penetrate casing and extend to the outside of casing, the inside of casing is divided into the accommodation space and the arc extinguishing chamber through the conductor, is equipped with the arc extinguishing medium layer on the inner wall of arc extinguishing chamber, the piston is slidably installed in the accommodation space, and the piston includes the ceramic part, and the plastic part is arranged on the top of ceramic part, the closed cavity is formed between the plastic part, the igniter and the inner wall of accommodation space, when the igniter is triggered, the high pressure gas in the closed cavity pushes the piston to move downward and cuts off the conductor, and stops between the fracture of conductor, the piston in the utility model can effectively resist the burning of high energy arc in the initial stage of arc, and the piston high temperature deformation is not prone to.

Description

Technical Field

[0001] This utility model relates to fuses, specifically to a pyrotechnic fuse. Background Technology

[0002] In a pyrotechnic fuse (also known as an activated fuse), the piston is the core moving component. When the igniter is triggered, the high-pressure gas instantly generated inside the cylinder pushes the piston downward, cutting the conductor to break the circuit. After triggering, the piston reaches its final position; at this point, the piston needs to withstand the arcing generated when the conductor is cut and needs to establish insulation between the broken ends of the conductor.

[0003] The cutting pistons of current mainstream pyrotechnic fuses are all made entirely of special engineering plastics. Cutting pistons made of engineering plastics are prone to high-temperature deformation during the entire operation of pyrotechnic fuses. Utility Model Content

[0004] The purpose of this invention is to solve the technical problem that pistons made of engineering plastics are prone to high-temperature deformation during the operation of pyrotechnic fuses, and to provide a pyrotechnic fuse.

[0005] To solve the above-mentioned technical problems, the technical solution provided by this utility model is as follows:

[0006] A pyrotechnic fuse includes a housing, an igniter at the top of the housing, a conductor in the middle of the housing, with both ends of the conductor penetrating the housing and extending to the outside of the housing; the interior of the housing is divided into an accommodating space and an arc-extinguishing chamber by the conductor, and an arc-extinguishing medium layer is provided on the inner wall of the arc-extinguishing chamber.

[0007] A piston is slidably installed within the accommodating space. The piston includes a ceramic part and a plastic part disposed on top of the ceramic part.

[0008] A sealed cavity is formed between the plastic part, the igniter and the inner wall of the accommodating space;

[0009] When the igniter is triggered, high-pressure gas is generated in the sealed chamber, which pushes the piston downward to cut the conductor and stops between the broken ends of the conductor.

[0010] Furthermore, a receiving groove is provided on the top of the ceramic part, and the plastic part is placed in the receiving groove.

[0011] Furthermore, the ceramic part is a ceramic material or a ceramic matrix composite material;

[0012] The plastic part is made of special engineering plastic.

[0013] Furthermore, cutting auxiliary grooves are provided on both sides of the bottom of the conductor near the side wall of the arc-extinguishing chamber;

[0014] When the piston moves downwards and cuts the conductor, the conductor's cutting auxiliary groove forms a break.

[0015] Furthermore, the bottom cross-section of the ceramic part is arc-shaped or trapezoidal.

[0016] Furthermore, the ceramic material is any one of alumina ceramic, aluminum nitride ceramic, or beryllium oxide ceramic.

[0017] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0018] 1. The pyrotechnic fuse provided by this utility model uses a combination of a plastic part and a ceramic part for the piston, that is, the upper part of the piston is plastic and the lower part is ceramic. When the igniter is triggered, high-pressure gas is generated in the sealed cavity formed between the piston, the igniter and the inner wall of the accommodating space to push the piston downward to cut the conductor. This allows the ceramic part to come into contact with the electric arc first, effectively resisting the burning of the high-energy electric arc in the early stage of arcing and making it less likely for the piston to deform at high temperature.

[0019] 2. The pyrotechnic fuse provided by this utility model can improve the cutting speed and reduce the overall system action time due to the high hardness of the ceramic part. At the same time, the piston adopts a combination of plastic and ceramic parts, which can reduce the ceramic volume and reduce manufacturing costs while making full use of the advantageous properties of ceramic materials. In addition, the plastic material at the tail can also reduce the overall brittleness of the piston to a certain extent. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structure of an embodiment of the present utility model;

[0021] Figure 2 This is a schematic diagram of the structure after the conductor is cut in an embodiment of this utility model;

[0022] Figure 3 This is a schematic diagram of the piston structure in an embodiment of the present invention;

[0023] Figure 4 This is a schematic diagram of the piston structure in other embodiments of this utility model.

[0024] Explanation of reference numerals in the attached drawings: 1-shell, 2-conductor, 3-accommodating space, 4-arc extinguishing chamber, 5-piston, 51-ceramic part, 52-plastic part, 6-igniter, 7-arc extinguishing medium layer, 8-cutting auxiliary groove. Detailed Implementation

[0025] The technical solutions of this utility model will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this utility model, and not all of them. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0026] like Figure 1 and Figure 2 As shown, a pyrotechnic fuse includes a housing 1, an igniter 6 is provided at the top of the housing 1, and a conductor 2 is provided in the middle of the housing 1. The two ends of the conductor 2 pass through the housing 1 and extend to the outside of the housing 1.

[0027] The interior of the shell 1 is divided into a accommodating space 3 and an arc-extinguishing chamber 4 by a conductor 2. An arc-extinguishing medium layer 7 is provided on the inner wall of the arc-extinguishing chamber 4.

[0028] A piston 5 is slidably installed within the accommodating space 3, such as Figure 3 As shown, the piston 5 includes a ceramic part 51 and a plastic part 52 disposed on the top of the ceramic part 51; wherein, the material of the ceramic part 51 is any one of alumina ceramic, aluminum nitride ceramic or beryllium oxide ceramic; and the material of the plastic part 52 is a special engineering plastic.

[0029] A sealed cavity is formed between the piston 5, the igniter 6 and the inner wall of the accommodating space 3;

[0030] When the igniter 6 is triggered, high-pressure gas is generated in the sealed cavity, which pushes the piston 5 downward to cut the conductor 2 and stops between the broken ends of the conductor 2. The piston 5 participates in the arc extinguishing process and absorbs the energy of the electric arc, thereby improving the breaking capacity of the pyrotechnic fuse.

[0031] In this embodiment, the piston 5 is composed of a ceramic part 51 and a plastic part 52 placed in the receiving groove of the ceramic part 51, which can reduce the cost of raw materials while effectively ensuring performance. At the same time, the ceramic part 51 (any one of alumina ceramic, aluminum nitride ceramic or beryllium oxide ceramic) has the characteristics of high temperature stability and arc resistance (the melting point of the ceramic part 51 is higher than 2000℃ and can withstand the high temperature arc of higher than 3000℃ when the conductor 2 is cut), which avoids the piston 5 from failing to break due to high temperature deformation or melting.

[0032] The ceramic part 51 has good insulation properties, which can effectively isolate the electric arc, prevent reignition, and improve the reliability of the break. Moreover, the ceramic part 51 of the piston 5 can participate in the arc extinguishing process after the conductor 2 is cut off, thereby reducing the arrangement of arc extinguishing materials and reducing the overall size of the device.

[0033] The ceramic part 51 is highly resistant to corrosive substances such as gunpowder gas and metal vapor, which can avoid the oxidation or sulfidation failure that may occur with existing special plastic cutting pistons.

[0034] In order to achieve a higher cutting rate of the high-temperature resistant combined cutting piston and thus achieve rapid arc extinguishing, cutting auxiliary grooves 8 are provided on both sides of the bottom of the conductor 2 near the side wall of the arc extinguishing chamber 4; when the piston 5 moves downward to cut the conductor 2, the cutting auxiliary grooves 8 of the conductor 2 form a break.

[0035] In order to prevent the ceramic part 51 from colliding and breaking with the conductor 2 during the process of the high-temperature cutting piston cutting the conductor 2, the cross-section of the bottom of the ceramic part 51 is arc-shaped or trapezoidal.

[0036] In other embodiments of this utility model, such as Figure 4 As shown, a receiving groove is provided on the top of the ceramic part 51; the plastic part 52 is placed in the receiving groove.

[0037] The above description is merely a specific embodiment of this utility model, but the protection scope of this utility model is not limited thereto. Any changes or substitutions within the technical scope disclosed in this utility model should be included within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the protection scope of the claims.

Claims

1. A pyrotechnic fuse, comprising a housing (1), an igniter (6) at the top of the housing (1), a conductor (2) in the middle of the housing (1), the two ends of the conductor (2) passing through the housing (1) and extending to the outside of the housing (1); the interior of the housing (1) is divided into an accommodating space (3) and an arc-extinguishing chamber (4) by the conductor (2), and an arc-extinguishing medium layer (7) is provided on the inner wall of the arc-extinguishing chamber (4); characterized in that: A piston (5) is slidably installed in the accommodating space (3). The piston (5) includes a ceramic part (51) and a plastic part (52) disposed on the top of the ceramic part (51). A sealed cavity is formed between the plastic part (52), the igniter (6) and the inner wall of the accommodating space (3); When the igniter (6) is triggered, high-pressure gas is generated in the sealed cavity, which pushes the piston (5) downward to cut the conductor (2) and stop between the broken ends of the conductor (2).

2. The pyrotechnic fuse according to claim 1, characterized in that: The top of the ceramic part (51) is provided with a receiving groove, and the plastic part (52) is placed in the receiving groove.

3. The pyrotechnic fuse according to claim 2, characterized in that: The ceramic part (51) is a ceramic material or a ceramic matrix composite material; The plastic part (52) is a special engineering plastic.

4. The pyrotechnic fuse according to claim 1, characterized in that: The bottom sides of the conductor (2) are provided with cutting auxiliary grooves (8) near the side walls of the arc-extinguishing chamber (4); When the piston (5) moves downward and cuts the conductor (2), the cutting auxiliary groove (8) of the conductor (2) forms a break.

5. The pyrotechnic fuse according to claim 2, characterized in that: The bottom cross-section of the ceramic part (51) is arc-shaped or trapezoidal.

6. The pyrotechnic fuse according to claim 3, characterized in that: The ceramic material is any one of alumina ceramic, aluminum nitride ceramic, or beryllium oxide ceramic.

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