DE7339426U - Pyrotechnic working cylinder, in particular for tensioning the straps of a safety belt or harness - Google Patents

Description

official file number G 73 394 26.0 Director National ...

89 Augsburg 22, 28, G. Lb / N R 9283

Directed by Nationale des Usines Renault 8/10 Avenue Emile ZoIe. Billancourt (Seine) France

and

Automobiles Peugeot

75 avenue de la Grande Army

Paris, France

Pyrotechnic working cylinder, in particular for tensioning the straps of a seat belt or harness.

The innovation relates to pyrotechnic working cylinders, in particular to working cylinders that serve the purpose of the bands a seat belt or a safety buckle device as used in motor vehicles tighten.

An application example for such a working cylinder has been described in FR-PS 2 180 151 and the The innovation relates to an embodiment of such a working cylinder.

It is known that these working cylinders generally have a cylinder jacket, a powder charge, a Explosion chamber, a piston firmly attached to a pull rod, a holding segment for holding the piston in its End position and holding parts for attaching the cylinder to a component connected to the vehicle body.

Kit of innovation aims to achieve an improvement, which consists in closing the end of the cylinder, which to be attached to the vehicle by means of a terminating part, which is also the holding segment for holding of the piston in its end position and the holding parts for attaching the working cylinder. To this end the end part is designed as a hollow head part that carries the holding parts for attaching the cylinder, and the The inner wall of the head part cooperates with the holding segment to hold the piston in its end position.

According to one embodiment of the terminating part, the working cylinder is adjustable in direction, and its lower end is a receptacle for a swivel ball head.

Further features and advantages of the innovation emerge from the description in conjunction with the drawings, the represent the following:

Fig. 1 with a partial longitudinal section through the working cylinder

the attachment of the cylinder to the vehicle body;

FIG. 2 shows a section along the line H-II in FIG. 1

From the drawings it can be seen that the working cylinder designated as a whole by 1 has a cylinder jacket 2, a piston 3 displaceable in the cylinder jacket 2 and a pull rod M · (piano wire), which with is rigidly connected to the piston and at its free end carries a fork head 5 to which the locks 6 are attached are, in which a not shown hook of a safety item intervenes.

The head of the working cylinder inserted into the cylinder jacket 2 contains the sealed passage 8 for the Ignition lines of the exploding charge 10 and seals 9, A spacer 11 placed around the pull rod 4 enables the volume of the explosion space 12 of the working cylinder 1 to be adjusted.

The piston 3 also has an annular seal 13 and a holding segment \ h which forms the device for locking the piston movement in its end position; this is described in more detail below.

The holding segment IH is designed as an expandable slotted ring which is accommodated in an annular groove 15 of the piston, the support of which against the cylinder jacket 2 prevents the piston from moving prematurely.

Incidentally, this effect could also be achieved with a thin pipe

achieve that the uivter pressure load is plastically deformable is and between the bottom of the working cylinder and the not pressurized side of the piston arranged is.

The working cylinder 1 has a device for fastening the cylinder jacket 2 to the body part 16.

For this purpose, the working cylinder is closed by a hollow head part 17, which is attached to the cylinder jacket 2 is screwed and the hemispherical bottom 18 forms the receptacle for a clement of a swivel ball head 19, which is centered with the aid of pins 20.

The swivel ball head element 19 is provided with a fastening device rigidly connected, which is formed by screws 21 and has a damping element 22 made of lead »the with the surface 2 3 of the piston 3 which is not dryekbsaufsehlagen cooperates in its end position.

The locking effect for the piston in its end position is created by the interaction of the spread SegjneniLS_14 with a shoulder 24, which is limited by the lower part of the cylinder jacket 2 and which protrudes from the inner wall of the hollow head part 17.

The method of operation of the working cylinder whose piston 3 held in its end position by the holding segment It that is then at the same time as the shoulder mentioned 2 4 and the groove 15 cooperates, which is the holder for the represents called segment.

So that the coming in one chamber of the working cylinder 1

7331426 -M. 7 *

Ingested air can be removed more easily, holes can be used 25 can be provided in the bottom of the working cylinder 1.

It can also be seen that the working cylinder 1 has an interposed elastic buffer 27 with a mounting bracket 26 is connected; the buffer 27 dampens the vibrations transmitted by the vehicle body that cause the can affect the correct work of the working cylinder.

Protection claims :

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Claims (2)

Protection claims 1. Pyrotechnic working cylinder »in particular for tensioning the straps of a safety belt or harness, with a cylinder jacket, a piston that can be moved in it, a pull rod firmly connected to the piston, a charge to be exploded, an explosion chamber, a holding segment to hold the piston in place its end position and holding parts for fastening the working cylinder, characterized in that the working cylinder (1) is closed at its end by a hollow head part (17), the inner wall of which with the holding segment (14) for holding the piston (3) in its on cooperates furthest advanced position, and that the head part (17) also contains the holding parts (19-11) for attaching the working cylinder (1). 2. Working cylinder according to claim 1, characterized in that the bottom of the hollow connected firmly to the cylinder jacket (2) of the piston (3) Head parts (17) form the receptacle for a swivel ball head element (19) which is rigidly connected to the fastening of the working cylinder and a damping element (22), the one with the non-pressurized Side (23) of the piston (3) interacts when it reaches its end position. 3 · Working cylinder according to claim. 1, thereby. characterized in that the holding segment for holding of the piston (3) in its end position from buckets expandable slotted ring (14) which is in a circumferential groove (15) of the piston (3) lies. Working cylinder according to claim 1 or 2, characterized in that a lower edge of the Cylinder jacket (2) of the piston (3) together with the inner wall of the hollow head part (1?) One in the end position This piston (3) acts as a shoulder (£ 4 ·) for the expandable, slotted ring (14).