Device for firing a pyrotechnic propellent composition

• US 6,240,848 B1
• Filed: 08/10/1998
• Issued: 06/05/2001
• Est. Priority Date: 11/17/1995
• Status: Expired due to Fees

• Current Assignee: Key Safety Systems, Inc. (Ningbo Junsheng Investment Group Co., Ltd.)
• Original Assignee: Breed Automotive Technology, Inc. (Ningbo Junsheng Investment Group Co., Ltd.)
• Inventors: Ludwig, Thomas, Specht, Martin
• Primary Examiner(s): Poon, Peter M.
• Assistant Examiner(s): Bergin, James S.
• Application Number:
  US09/068,802
• Time in Patent Office: 1,030 Days
• Field of Search: 102/216, 102/247, 102/252, 102/273, 102/272, 102/274, 102/249, 102/251, 891/36, 891/32, 89/271.1, 89/271.3, 89/271.4, 89/273, 280/731, 280/734
• US Class Current: 102/216
• CPC Class Codes: B60R 22/4652 Mechanical triggering means therefor also adapted for air bag inflators B60R21/33
• CPC Class Codes: F42C 1/04 operating by inertia of members on impact

Abstract

A device for firing a pyrotechnic propellent composition having a sensor mass (3) which for firing purposes releases a locking lever (4) which in the rest position bears lockingly against a ring (9) of the firing pin (1).

Claims

1. A device for firing a pyrotechnic propellant composition comprising:

a firing pin drivable by a drive spring, a locking means which holds the drive spring in a prestressed rest condition and having a locking lever, which is supported at a stationary location and which is subjected to the action of a release moment due to the prestressing of the drive spring and being held in the rest position by a sensor mass, which is moved, away from the locking lever, upon excessive acceleration and by which the locking means can be released, wherein the firing pin (1) is held in a prepositioned condition with respect to a firing device of the pyrotechnic propellant composition, and a firing pin actuating means (9;

33) is provided which is movable with respect to the firing pin (1) and movable about a pivot axis and which is drivable by the drive spring (2;

34) and can be impacted against the firing pin (1).

2. A device according to claim 1 wherein the locking lever (4), which in the rest position is supported at least at two support locations (5, 6), these two support locations are positioned on one side of a pivot point of the lever, wherein a first of the support locations (5) carries the drive force of the drive spring (2) and a second of the support locations (6) bears against the sensor housing (7).

3. A device according to claim 1 wherein the firing pin (1) is linearly drivable in the direction of its longitudinal axis (firing pin axis (8)).

4. A device according to claim 1 wherein the drive spring (2) is in the form of a coil spring which acts on a ring (9) on the firing pin (1) for transmission of the drive force.

5. A device according to claim 1 wherein the locking lever (4) has a third support location (10) which bears against the sensor mass (3) in the rest position.

6. A device according to claim 1 wherein the first support location (5) forms an axis, which is not stationary, of the locking lever (4) which is of a double-sided configuration, and the second and third support locations (6, 10) are provided at the ends of the lever.

7. A device according to claim 1 wherein the sensor mass (3) is guided by means of a parallel guide means (11) on the sensor housing (7).

8. A device according to claim 7 wherein the parallel guide means (11) has transverse link springs.

9. A device according to claim 7 wherein the parallel guide means (11) has an oscillation-damping action.

10. A device according to claim 1 wherein the sensor mass (3) is guided in parallel relationship to the firing pin axis (8).

11. A device according to claim 1 wherein the sensor mass (3) is movable in opposite relationship to the direction of the force of a sensor spring (12).

12. A device according to claim 11 wherein, when installed in a vehicle, the direction of the force of the sensor spring (12) is directed in opposite relationship to the direction (13) of forward travel of vehicle.

13. A device according to claim 1 wherein the drive spring (2;

34) drives the firing pin actuating means (33) by way of a lever arm (36).

14. A device according to claim 1 wherein after release of the sensor mass (3) from the third support surface (10) the locking lever (4) is movable under the influence of the release moment about a pivot point (37) supported at the firing pin actuating means (9).

15. A device according to claim 1 wherein the firing pin has an impact surface (38) for the firing pin actuating means, which impact surface is of a larger area than the cross-sectional area of the remaining part of the firing pin.