JP2023032209A - gas generator - Google Patents

Abstract

To provide a gas generator which enables improvement of attachability to a pretensioner.SOLUTION: A gas generator 1 includes: a cap 2 in which an opening is formed at one end side and the other end side is closed and which houses a gas generating agent 7 therein; a holder 3 which is attached to the cup 2 so as to close the opening and seals the gas generating agent 7; and a squib 4 which is held by the holder 3 and ignites the gas generating agent 7 based on a signal from the exterior. The cup 2 has a pointed part 2b at the other end side.SELECTED DRAWING: Figure 1

Description

The present invention relates to gas generators.

2. Description of the Related Art Conventionally, in a seat belt device attached to a vehicle seat of an automobile or the like, in an emergency (hereinafter simply referred to as "emergency") in which the vehicle decelerates more than usual in the event of a collision, the occupant is forced to use the seat belt. be restrained. A three-point seat belt system is widely known as a seat belt system. For example, in a three-point seat belt system, a seat belt pulled out from a retractor is guided by a belt guide anchor, and its tip is fixed to the vehicle body. A tongue is slidably supported on the seat belt guided by the belt guide anchor. The seat belt is worn by the occupant by engaging the tongue with a buckle fixed to the vehicle body.

When the seat belt is attached to the occupant, the seat belt between the belt guide anchor and the tongue functions as a shoulder belt attached to the shoulder and chest of the occupant. Also, the seat belt between the tip fixed to the vehicle body and the tongue functions as a lap belt worn around the occupant's lap (waist). In an emergency, the lock mechanism of the retractor is activated to prevent the seat belt from being pulled out, so that the shoulder belt restrains the shoulders and chest of the occupant and the lap belt restrains the waist of the occupant.

A seat belt device is known in which a retractor is provided with a pretensioner. In the early stages of an emergency, the pretensioner activates to quickly reduce the slack in the seat belt, improving the restraint effect on the occupants. The pretensioner operates with gas generated from the gas generator. In the conventional gas generator, a gas generating agent is contained in a cylindrical cylinder with a flat surface at the tip, and a holder integrated with an igniter is fitted into the rear end opening of the cylinder to generate gas. It has a configuration in which the generating agent is sealed (see Patent Document 1, for example).

In the retractor, the gas generator is provided at one end of a spring for position regulation, and a piston is arranged at the other end of the spring via a piston ring. As described above, the tip of the gas generator is a flat surface, and one end of the spring comes into contact with this flat surface, so it is sometimes difficult to stably attach the seat surface of the spring.

Japanese Patent Application Laid-Open No. 2001-106017

An object of the present invention is to provide a gas generator that can be easily attached to a pretensioner.

The gas generator of the present invention has an opening at one end and a closed end at the other end, a cup containing a gas generating agent therein, and attached to the cup so as to close the opening. A holder that seals a gas generating agent, and a squib that is held by the holder and ignites the gas generating agent based on a signal from the outside, and the cup has a pointed head on the other end side. is.

In one aspect of the present invention, the cup has a cylindrical portion with one end serving as the opening, and the pointed head is connected to the other end of the cylindrical portion.

In one aspect of the present invention, a pair of parallel flat surfaces are formed on a side surface of the cylindrical portion on the other end side.

In one aspect of the present invention, the cusp has a pyramidal shape, and slits are formed in the sides.

In one aspect of the present invention, the cusp has a conical shape, and a plurality of slits extending in the ridgeline direction are formed in the side surface.

ADVANTAGE OF THE INVENTION According to this invention, the attachment property to a pretensioner can be improved.

1 is a perspective view of a gas generator according to an embodiment of the invention; FIG. It is a side view of a gas generator. 3 is a cross-sectional view taken along line III-III of FIG. 2; FIG. FIG. 4 is a sectional view taken along line IV-IV of FIG. 3; 1 is a schematic diagram of a pretensioner; FIG. It is a figure which shows the connection structure of a gas generator and a spring. 1 is a schematic diagram of a pretensioner; FIG. FIG. 4 is a perspective view of a gas generator according to another embodiment;

A gas generator according to an embodiment of the present invention will be described with reference to FIGS. 1 to 4. FIG. 1 is a perspective view of the gas generator 1, FIG. 2 is a side view of the gas generator, FIG. 3 is a sectional view taken along line III-III of FIG. 2, and FIG. 4 is a sectional view taken along line IV-IV of FIG.

The gas generator 1 comprises a metal cup 2 containing a gas generating agent 7, a resin holder 3 holding a squib 4, and a connector section to which a harness for transmitting a signal from a vehicle collision detection means is connected. 6. A squib 4 serving as an igniter ignites based on a signal from the collision detection means, and the gas generating agent 7 burns to generate gas.

The material of the cup 2 is not particularly limited, and may be, for example, metal such as stainless steel or aluminum, or non-metal such as POM or nylon. The material of the holder 3 is not particularly limited, and is polyethylene terephthalate, for example.

The connector portion 6 has electrode pins 5 and the like connected to the squib 4 . The connector portion 6 may be provided with a shorting clip (not shown) as required. The shorting clip prevents malfunction of the gas generator 1 due to electrostatic discharge or the like. By inserting the connector of the harness into the connector portion 6, the short circuit is released.

The cup 7 has a cylindrical portion 2a with an opening at one end (rear end) in the cylinder axis direction, and a pyramid-shaped cusp 2b connected to the other end (front end) of the cylindrical portion 2a. By fitting the holder 3 into the opening on one end side of the cylindrical portion 2a, the opening is closed and the gas generating agent 7 is sealed. A method of attaching the cup 7 and the holder 3 is not particularly limited, and a known method such as caulking can be used.

The inner diameter of the cylindrical portion 2a is about 1 cm to 2 cm, and the length (in the horizontal direction in FIG. 2) is about 2 cm to 4 cm. The length of the cusp 2b is about 0.5 cm to 1 cm.

As shown in FIGS. 1 to 3, on the other end side of the cylindrical portion 2a, part of the side surface may be a pair of flat surfaces 2c that are (almost) parallel to each other instead of the curved surface.

As shown in FIG. 4, a slit is formed in the side part H of the pyramidal cusp 2b, and the thickness is smaller than the side part S of the cusp 2b. In this example, the cusp 2b has a hexagonal pyramid shape, but it may have another shape such as a triangular pyramid or a square pyramid.

By forming a slit in the side portion H, the gas generating agent 7 is ignited and burned to generate a large amount of gas. A side portion S of is bent outward to form a gas discharge port, and gas is discharged to the outside.

This gas generator 1 is used, for example, in a pretensioner 10 provided in a retractor of a seatbelt device, as shown in FIGS.

The pretensioner 10 includes a gas generator 1, a piston 12 that operates with the gas generated by the gas generator 1 to generate driving force, a piston ring 13 attached to the piston 12, and the driving force generated by the piston 12. to the spool of the seat belt retractor, the pipe 11 guiding the piston 12 and the many balls 15, and the piston 12 and the many balls 15 are biased in the same direction as the piston 12 is operated by gas. and a spring 14 that

The gas generator 1 is arranged on one end side of the spring 14, and the piston 12 is arranged on the other end side. As shown in FIG. 6, the pointed portion 2b of the gas generator 1 fits inside the spring 14. As shown in FIG. Since the pointed head 2b can be used as a seat for the spring 14, the position of the spring 14 is stabilized. Thus, by using the gas generator 1 according to this embodiment, it is possible to improve the mountability to the pretensioner.

A tongue that divides the seat belt into a shoulder belt and a lap belt is slidably supported on the seat belt, and the tongue is detachable from the buckle. The gas generator 1 may be provided in a pretensioner that pulls the tip of a seat belt pulled out from a retractor or a pretensioner that pulls a buckle. An example of such a pretensioner 20 is shown in FIG.

The pretensioner 20 includes a wire 22 having one end connected to the seat belt, a piston 23 connected to the other end of the wire 22, a cylinder 21 slidably housing the piston 23, and the wire 22 passing through the wire. and a housing 24 for holding the cylinder 21 together with the piston 23 .

In the housing 24, the gas flow path 24a connected to the gas generator mounting location is narrower than the gas generator mounting location. When the gas generator 1 according to this embodiment is attached, the cusp 2b enters into the gas flow path 24 . Therefore, compared to the conventional gas generator which has a flat tip and does not enter the gas flow path 24, it is possible to increase the capacity of the gas generating agent.

In the above embodiment, the cup 7 has a cylindrical portion 2a and a pyramidal cusp 2b. However, as shown in the gas generator 1A of FIG. It may be 2A.

The cusps 2b, 2A may be conical, and the sides are provided with a plurality of slits extending in the ridgeline direction.

The above-described embodiment is an example of the present invention, and the present invention may be in forms other than those shown in the drawings.

REFERENCE SIGNS LIST 1 gas generator 2 cup 2a cylindrical portion 2b point 3 holder 4 squib 6 connector portion 7 gas generating agent

Claims (5)

a cup which has an opening at one end and is closed at the other end and contains a gas generating agent therein;
a holder attached to the cup to close the opening and seal the gas generant;
a squib held by the holder and igniting the gas generating agent based on a signal from the outside;
with
The gas generator, wherein the cup has a pointed head on the other end side. 2. The gas generator according to claim 1, wherein the cup has a cylindrical portion with one end serving as the opening, and the pointed portion continues to the other end of the cylindrical portion. 3. The gas generator according to claim 2, wherein a pair of parallel flat surfaces are formed on the side surface of the cylindrical portion on the other end side. 4. The gas generator according to any one of claims 1 to 3, wherein the cusp has a pyramidal shape, and slits are formed in the sides thereof. 4. The gas generator according to any one of claims 1 to 3, wherein the cusp has a conical shape, and a plurality of slits extending in the ridgeline direction are formed on the side surface.

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