Pyrotechnic type gas generator

Abstract

The utility model discloses a smoke and fire type gas generator, and particularly relates to the technical field of gas generators. The generator body comprises a shell, an inner cylinder is arranged in the shell, a gap is formed between the inner cylinder and the shell, a buffer device is arranged in the inner cylinder, a filter cylinder is arranged at the bottom of the shell, a filter screen cover is arranged on the upper portion of the filter cylinder, and a gap is formed between the inner cylinder and the filter screen cover. Through the arrangement of the buffer device, the abnormal sound of the generator main body can be effectively reduced; gaps are formed between the inner cylinder and the shell as well as between the inner cylinder and the filter screen cover, the inner cylinder expands to be attached to the shell when the generator body is exploded, the combustion space of the gas production medicine extends to the upper portion of the filter screen cover from the inner cylinder in the axial direction, the internal pressure of the generator can be effectively reduced, and the safety rate is improved; and the filter screen cover can prevent the gas-producing agent from entering the filter cartridge, so that the stable combustion of the gas-producing agent is ensured.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of gas generator, more specifically to a pyrotechnic gas generator. BACKGROUND

[0002] The pyrotechnic gas generator is a device that uses the combustion of pyrotechnic charges to produce gas. The charges are ignited by an igniter, and they burn rapidly, producing a large amount of high-temperature and high-pressure gas in a very short time. These gases burst through the relevant components of the generator and enter the target space or equipment to achieve a specific function. For example, in an automobile airbag system, the gas bursts through the airbag cover to make the airbag rapidly expand and deploy.

[0003] However, most existing pyrotechnic generators use metal brackets to fix the gas-producing charges and prevent abnormal noise. The manufacturing process of the components and the generator is complex, the cost is high, and the gas-producing charges may even be crushed. In order to ensure the safety of the generator, a relatively thick shell is usually used, which is heavy and increases the production cost. In addition, the gas-producing charges are usually burned inside the generator, resulting in high gas temperature and easy damage to the outside. SUMMARY

[0004] In order to overcome the above-mentioned defects of the prior art, the utility model provides a pyrotechnic gas generator. The buffer device can effectively reduce the abnormal noise of the generator main body. The buffer device has a passage for gas flow, which can transfer the heat of the transmission charge to the gas-producing charge, making the combustion of the gas-producing charge more stable. The buffer device also avoids crushing the gas-producing charge. In addition, a gap is provided between the inner cylinder and the shell, and between the bottom of the inner cylinder and the filter screen cover. When detonating, the combustion space of the gas-producing charge is increased, which can reduce the internal pressure and improve the safety rate. The filter screen cover is arranged on the upper part of the filter cartridge to prevent the gas-producing charge from entering the inside of the filter cartridge. This not only makes the combustion of the gas-producing charge stable, but also reduces the gas temperature.

[0005] To achieve the above-mentioned purpose, the utility model provides the following technical scheme: a pyrotechnic gas generator, comprising a generator main body;

[0006] The generator main body comprises a shell, the shell is internally provided with an inner cylinder, a certain gap is arranged between the inner cylinder and the shell, the inner cylinder is internally provided with a buffer device, and the inner cylinder is separated into a transmission charge space and a gas-producing charge space by the buffer device. The transmission charge space is arranged at the top of the gas-producing charge space. The bottom of the shell is closed, and a filter cartridge is arranged at the bottom of the shell. A filter screen cover is arranged on the upper part of the filter cartridge, and a gap is arranged between the inner cylinder and the filter screen cover.

[0007] In a preferred embodiment, the buffer device is a polygonal buffer gasket, and the polygonal buffer gasket and the inner wall of the inner cylinder form a gap, and the gas generated by the combustion of the transfer charge when the generator body is detonated can be uniformly transmitted to the gas generating charge through the gap between the polygonal buffer gasket and the inner cylinder.

[0008] In a preferred embodiment, the buffer device can also be a spring, and the spring and the inner wall of the inner cylinder form a gap, and the gas generated by the combustion of the transfer charge when the generator body is detonated can be uniformly transmitted to the gas generating charge through the spring gap.

[0009] In a preferred embodiment, the filter screen cover is designed in a conical shape, the taper of the conical filter screen cover is 10°-80°, and the size of the mesh hole on the filter screen cover is 30mm 2 -120mm 2 .

[0010] In a preferred embodiment, the filter screen cover is designed in a straight cylindrical shape, and the size of the mesh hole on the filter screen cover is 30mm 2 -120mm 2 .

[0011] The inner cylinder is internally provided with an igniter, and the igniter is arranged at the top of the transfer charge space, the top end of the igniter penetrates through the inner cylinder and extends to the inside of the top end of the outer shell, and the bottom of the inner cylinder is provided with a weakened portion for easy opening.

[0012] In a preferred embodiment, the inside of the bottom end of the outer shell is provided with a filter cartridge, the top end of the filter cartridge is externally welded with a filter screen cover, and the outside of the filter screen cover is in contact with the inner wall of the outer shell; the bottom end of the filter screen cover extends into the inside of the filter cartridge, and the filter screen cover prevents the gas generating charge from entering the filter cartridge.

[0013] In a preferred embodiment, the end weakened portion of the inner cylinder is designed as a cross-shaped groove or a rice-shaped groove.

[0014] The technical effects and advantages of the utility model are as follows:

[0015] Through the arrangement of the buffer device, the abnormal sound of the generator body can be effectively reduced, and the buffer device is provided with a channel for airflow to pass through, so that the airflow can transmit the heat of the transfer charge to the gas generating charge, and the combustion of the gas generating charge is more stable.

[0016] By providing gaps between the outer shell and the inner cylinder and between the inner cylinder and the filter screen cover, after the generator body is detonated, the inner cylinder expands to be attached to the outer shell, the combustion space of the gas generating charge is extended to the filter screen cover, and the combustion space is increased, so that the internal pressure can be effectively reduced, and the safety rate is improved.

[0017] By setting the filter screen cover on the upper part of the filter cartridge, the filter screen cover is fixed on the filter cartridge by welding or other fixed connection mode, the filter screen cover prevents the gas generating agent from entering the inside of the filter cartridge during the detonation, the gas generating agent can be burned stably, and the gas generating agent is prevented from burning in the inner cylinder, the filtering efficiency is improved, and the outlet gas temperature is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 It is the overall structure schematic view of the utility model;

[0019] Figure 2 It is the shell sectional view of the utility model;

[0020] Figure 3 It is the spring front view of the utility model

[0021] Figure 4 It is the polygonal buffer gasket front view of the utility model;

[0022] Figure 5 It is the inner cylinder bottom view of the utility model;

[0023] Figure 6 It is the filter screen cover explosion view of the utility model.

[0024] The figure mark is: 1, shell; 2, inner cylinder; 3, buffer device; 31, polygonal buffer gasket; 32, spring; 4, transfer fire agent space; 5, gas generating agent space; 6, igniter; 7, cross slot; 8, filter cartridge; 9, filter screen cover. DETAILED DESCRIPTION

[0025] The technical scheme in the embodiments of the utility model will be described clearly and completely in conjunction with the drawings in the embodiments of the utility model, obviously, the described embodiments are only part of the embodiments of the utility model, not all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by the person skilled in the art without creative labor are within the protection scope of the utility model.

[0026] Referring to the drawings in the description Figures 1-6 The utility model provides a kind of pyrotechnic gas generator, including generator main body;

[0027] As Figure 3 And 4As shown, the generator body comprises a shell 1, the shell 1 is internally provided with an inner cylinder 2, a gap is arranged between the inner cylinder 2 and the shell 1, the inner cylinder 2 is internally provided with a buffer device 3, and the inner cylinder 2 is divided into a transfer charge space 4 and a gas generating charge space 5 by the buffer device 3, the transfer charge space 4 is arranged at the top of the gas generating charge space 5, the bottom of the shell 1 is closed, and the bottom of the shell 1 is provided with a filter cylinder 8, the upper part of the filter cylinder 8 is provided with a filter screen cover 9, and a gap is arranged between the inner cylinder 2 and the filter screen cover 9;

[0028] The inner cylinder 2 is internally provided with an igniter 6 at the top end, and the igniter 6 is arranged at the top of the transfer charge space 4, the top end of the igniter 6 penetrates the inner cylinder 2 and extends to the inside of the top end of the shell 1, and the bottom of the inner cylinder 2 is processed with a weakened portion 7 for easy opening.

[0029] In use, the igniter 6 ignites the transfer charge in the transfer charge space 4, after the transfer charge is detonated, the heat is transmitted to the gas generating charge in the gas generating charge space 5 through the airflow passing through the gap designed by the buffer device 3, because the buffer device is a polygonal buffer gasket 31, and a gap is formed between the polygonal buffer gasket 31 and the inner wall of the inner cylinder 2, the buffer device can also be a spring 32, and a gap is formed between the spring 32 and the inner wall of the inner cylinder 2, the arrangement of the buffer device 3 can effectively reduce the abnormal noise of the generator body;

[0030] Because the weakened portion 7 changes the stress distribution at the bottom end of the inner cylinder 2, when the inner cylinder 2 is subjected to internal pressure, the stress is mainly concentrated at the weakened portion 7, forming a stress concentration point, when the internal pressure reaches a certain degree, the inner cylinder 2 will first break at the weakened portion 7. There is a gap between the inner cylinder 2 and the shell 1, when the internal pressure is greater, the inner cylinder 2 expands outward to fit the shell 1, and the bottom of the inner cylinder 2 and the filter screen cover 9 also have a certain gap, so the combustion space of the gas generating charge is no longer limited to the initial space inside the inner cylinder 2, but expands in the direction of the inner cylinder after expansion and the filter screen cover 9. The expansion of this space makes the gas have a larger volume to buffer the pressure, avoiding the excessive accumulation of pressure in a small space, thereby effectively reducing the internal pressure and improving the safety rate.

[0031] In order to facilitate the filtration of the gas generating charge and reduce the outlet gas temperature, as shown Figure 2 As shown, the bottom end of the shell 1 is internally provided with a filter cylinder 8, the top end of the filter cylinder 8 is externally fixedly connected with a filter screen cover 9, the outer part of the filter screen cover 9 is in contact with the inner wall of the shell 1; the bottom end of the filter screen cover 9 extends into the inside of the filter cylinder 8, the filter screen cover 9 prevents the gas generating charge from entering the filter cylinder 8, the cross section of the filter screen cover 9 is designed as a cone or a straight cylinder, if designed as a cone, the taper of the filter screen cover 9 is designed as 10°-80°, the area of the mesh hole on the filter screen cover 9 is designed as 30mm 2 -120mm 2The filter screen cover 9 is arranged so that the gas has a larger passing area, avoids the gas gathering in the combustion chamber, effectively reduces the pressure in the combustion chamber, and improves the safety rate; in addition, the filter screen cover 9 can block the gas production medicine in the combustion from entering the inside of the filter cartridge 8, avoids the temperature of the filter cartridge 8 being too high, improves the filtering and cooling effect of the filter cartridge 8, and reduces the gas outlet temperature.

[0032] Finally: the above only for the preferred embodiments of the utility model have, and do not for limiting the utility model, any modification, equivalent replacement, improvement etc. that is made within the spirit and principle of the utility model, should be contained in the protection scope of the utility model.

Claims

1. A pyrotechnic gas generator, characterized in that: Including the generator body; The generator body includes an outer shell (1), an inner cylinder (2) is provided inside the outer shell (1), a certain gap is provided between the inner cylinder (2) and the outer shell (1), a buffer device (3) is provided inside the inner cylinder (2), and the inner cylinder (2) is divided into a propellant space (4) and a gas-generating space (5) by the buffer device (3), the propellant space (4) is located at the top of the gas-generating space (5), the bottom of the outer shell (1) is closed, and a filter cylinder (8) is provided at the bottom of the outer shell (1), a filter screen cover (9) is provided on the upper part of the filter cylinder (8), and a gap is provided between the inner cylinder (2) and the filter screen cover (9); The inner cylinder (2) is provided with an ignition device (6) at the top and the ignition device (6) is located at the top of the propellant space (4). The top of the ignition device (6) penetrates the inner cylinder (2) and extends to the top of the outer shell (1). The bottom of the inner cylinder (2) is processed with a weakened part (7) that is easy to open.

2. The pyrotechnic gas generator according to claim 1, characterized in that: The buffer device is a polygonal buffer pad (31), and a gap is formed between the polygonal buffer pad (31) and the inner wall of the inner cylinder (2).

3. A pyrotechnic gas generator according to claim 1, characterized in that: The buffer device may also be a spring (32), and a gap is formed between the spring (32) and the inner wall of the inner cylinder (2).

4. A pyrotechnic gas generator according to claim 1, characterized in that: There is a certain gap between the inner cylinder (2) and the outer shell (1), and there is also a gap between the bottom of the inner cylinder (2) and the filter screen (9). When the generator body is ignited, the inner cylinder (2) expands to fit with the outer shell (1), and the combustion space of the gas-producing drug extends axially from the inner cylinder (2) to the upper part of the filter screen (9).

5. A pyrotechnic gas generator according to claim 1, characterized in that: The bottom of the outer shell (1) is provided with a filter cylinder (8), and a filter screen (9) is fixedly connected to the top of the filter cylinder (8). The outside of the filter screen (9) is in contact with the inner wall of the outer shell (1). The bottom of the filter screen (9) extends into the filter cylinder (8), and the filter screen (9) prevents the gas-generating drug from entering the filter cylinder (8).

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