After-firing safety device in a projectile with percussion fuze
Patent 4938139 Issued on July 3, 1990. Estimated Expiration Date: 
June 6, 2009. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
June 6, 2009. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent References 3030886 3249051 Arming fuze for artillery shell Fuse with a detonator Rotating cage security device for a gyratory projectile Safing and arming device Patent #: 4662279 InventorsAssigneeApplicationNo. 363282 filed on 06/06/1989US Classes:102/249, With setback latch102/233, With setback latch102/240, Spiral band102/257Timer operated impacting device latchExaminersPrimary: Brown, David H.Attorney, Agent or FirmForeign Patent References
International ClassesF42C 015/04F42C 015/20 Foreign Application Priority Data1987-11-20 DEAbstractAn after-firing safety device in a projectile with percussion fuze includes a spiral spring set having at least three springs wound up in series with respectively opposite directions. The spring set, maintained under tension by a cage, starts to uncoil as soon as the cage slides off the spiral spring set on account of the acceleration of the projectile during firing. The time elapsing until a central aperture has been entirely vacated depends on the number of springs, the spring lengh, the spring tension, and the friction characteristic. The after-firing safety device is equally well suited for spinning projectiles as well as nonspinning projectiles. | |
