Ring pellets for gas generators

• US 5,101,730 A
• Filed: 07/13/1990
• Issued: 04/07/1992
• Est. Priority Date: 07/13/1989
• Status: Expired due to Fees

• Current Assignee: Dynamit Nobel AG
• Original Assignee: Dynamit Nobel AG
• Inventors: Bender, Richard, Scheiderer, Gerrit, Winkler, Hans
• Primary Examiner(s): Nelson, Peter A.
• Application Number:
  US07/552,118
• Time in Patent Office: 634 Days
• Field of Search: 86/10, 102/373, 102/288, 102/289
• US Class Current: 102/288
• CPC Class Codes: B60R 21/2644 using only solid reacting substances, e.g. pellets, powder
• CPC Class Codes: F42B 5/16 characterised by composition or physical dimensions or form of propellant charge, with or without projectile, or powder chemical composition C06B; F42B5/24 takes precedence

Abstract

Ring pellets for gas generators exhibit optimum reaction rates by having configurations which optimize such rates. The pellet has a central ignition duct; from the latter, outlet channels extend radially toward a rim of the pellet. Specific embodiments contain, on the topside and underside of the pellets, either conical recesses or annular channels or both. The pellets preferably exhibit a proportion of surface area/unit weight of from 4 to 7 cm² /g, which can be set by variation of the channels and, respectively, of the recesses to obtain a desired value. The higher this value, the greater the reaction rate. The ring pellets are especially well suited for airbag generators which must display differently high reaction rates on the driver'"'"'s side and on the front-seat passenger'"'"'s side, and which are to exhibit at the same time a high breaking and abrasion stability.

Claims

1. A ring pellet for gas generators formed of a gas-releasing material, said pellet having a central, axially symmetrical channel extending therethrough and outlet channels on the topside and/or underside of the pellet extending radially from the central channel to an outer rim or periphery of the pellet.

2. A ring pellet according to claim 1, wherein the outlet channels are arranged symmetrically to the central channel.

3. A ring pellet according to claim 1, wherein the pellet has on the topside and underside the same number of outlet channels.

4. A ring pellet according to claim 2, wherein the pellet has on the topside and underside the same number of outlet channels.

5. A ring pellet according to claim 1, wherein the outlet channels on the topside of the pellets are arranged offset with respect to the outlet channels on the underside of the pellet.

6. A ring pellet according to claim 2, wherein the outlet channels on the topside of the pellets are arranged offset with respect to the outlet channels on the underside of the pellet.

7. A ring pellet according to claim 1, wherein the outlet channels each have a depth corresponding maximally to one-third of the total height of the pellet.

8. A ring pellet according to claim 2, wherein the outlet channels each have a depth corresponding maximally to one-third of the total height of the pellet.

9. A ring pellet according to claim 1, wherein the central channel includes conical recesses arranged axially symmetrically and surrounding a central duct extending through the pellet in the topside and the underside of the pellet, respectively, the outlet channels terminating in said recesses.

10. A ring pellet according to claim 2, wherein the central channel includes conical recesses arranged axially symmetrically and surrounding a central duct extending through the pellet in the topside and the underside of the pellet, respectively, the outlet channels terminating in said recesses.

11. A ring pellet according to claim 9, characterized in that the pellet has a surface area/weight ratio ranging from 3 to 7 cm² /g.

12. A ring pellet according to claim 10, characterized in that the pellet has a surface area/weight ratio ranging from 3 to 7 cm² /g.

13. A ring pellet according to claim 1, wherein the pellet has a centrally symmetrical annular channel arranged between the central channel and the rim of the pellet.

14. A ring pellet according to claim 2, wherein the pellet has a centrally symmetrical annular channel arranged between the central channel and the rim of the pellet.

15. A ring pellet according to claim 13, wherein the pellet has a surface area/weight ratio ranging from 4 to 8 cm² /g.

16. A ring pellet according to claim 9, wherein the pellet has a centrally symmetrical annular channel arranged between the central channel and the rim of the pellet.

17. A ring pellet according to claim 10, wherein the pellet has a centrally symmetrical annular channel arranged between the central channel and the rim of the pellet.