US3018734A

US3018734A - Delay firing mechanism

Info

Publication number: US3018734A
Application number: US549919A
Authority: US
Inventors: Eggman Max Earl
Original assignee: MAGUAVOX Co
Current assignee: MAGUAVOX Co
Priority date: 1955-11-30
Filing date: 1955-11-30
Publication date: 1962-01-30
Anticipated expiration: 1979-01-30

Description

1962 M. E. EGGMAN 3,018,734

DELAY FIRING MECHANISM Filed Nov. 50, 1955 INVEN TOR. Mex f. Eswmm 3,018,734 Patented Jan. 30, 1962 3,018,734 DELAY FG MECHANISM Max Earl Eggman, Fort Wayne, Inch, assignor to The Magnavox Company, Fort Wayne, Ind, a corporation Filed Nov. 30, 1955, Ser. No. 549,919 6 Claims. ((31. 10275) This invention relates generally to firing mechanisms for impact-responsive projectiles and more particularly it relates to a delayed impact mechanism especially adapted for use in grenades, mortar shells, rockets, bombs, and the like.

Conventional firing mechanisms for grenades, mortar shells, and other impact-responsive projectiles are relatively complex and expensive and require close tolerances between parts. This is especially true where it is desired to provide delayed firing after actual impact of the projectile with the target.

The principal object of this invention is to provide a simple and inexpensive firing mechanism for projectiles such as grenades, mortar shells, bombs, and the like, wherein there is delayed firing after impact with a target.

Another object of this invention is to provide a delayedimpact mechanism for projectiles of various types which does not require spinning action or setback of the firing mechanism at the time that the projectile is launched or at the time that the projectile actually contacts its target.

Still another object of this invention is to provide a firing mechanism responsive to impact with a target which will provide delayed detonation of a projectile.

In accordance with this invention there is provided a delayed impact firing mechanism for grenades, mortar shells, bombs, or other projectiles comprising a sliding device having a detonator pin, means normally preventing said sliding device from moving the detonator pin into engagement with the detonator in response to impact, and a control shaft which may be actuated to arm the mechanism by moving said sliding device into such a position that it is free to respond to the force of impact with a target to move the detonator pin into engagement with a detonator after a certain time-delay.

The full nature of the invention will be understoodfrom the accompanying drawings and the following description and claims:

FIG. 1 is a longitudinal cross section of a portion of a projectile including the firing mechanism as provided in accordance with this invention; and

FIG. 2 is a cross section taken on line 2-2 of FIG. 1.

Referring to the drawings, a portion of a projectile such as a hand grenade, mortar shell, or bomb is illustrated in FIG. 1, wherein the hand grenade or other projectile comprises a casing which may be the outer casing of the projectile or an inner casing adapted to house the mechanism of the invention. Within casing 10 there is a cylindrical holder 11 for supporting an explosive charge 12. A primer 14 may be nested within the charge 12 in conventional manner.

For detonating the primer 14, there is provided a slider 15 fitted in sliding relation to casing 10 and including a striker wire or firing pin 7 having a stabbing point thereon arranged in alignment with primer 14. A slider stop 17 may be arranged in the way of the slider 15 and secured to casing 10 by means of a pin 18 nested within stop member 17 and projecting into the casing 10, as shown in FIG. 1. The stop member 17 includes a slot 19 for receiving the slider lug 20 which projects outwardly on the main body portion of slider 15 and which supports the firing pin 7. Lug 20 is illustrated in alignment with the slot 19, whereby the mechanism is in position to he fired in response to impact with the target.

In order normally to prevent operation of the mechanism, slider 15 may be mounted on a rotatable shaft 21 and keyed thereto by providing a key slot 22 in shaft 21 and arranging the firing pin 7 to project into slot 22. Shaft 21 is supported at one end within the end plate 23, attached to casing 10 and at the other end in a locking disk 24 keyed as shown at 24a on the end of shaft 21 and resting on stop member 17 for rotation with respect thereto. Disk 24 includes a notch 25 which may normally be disposed out of alignment with a locking pin 26 slidably mounted within the charge holder 11. The movement of locking pin 26 into notch 25 may also be used to release a rotor, shutter or other interrupting device in the explosive train.

The slider 15 normally rests on the coil spring 28, one end of which may be supported by end plate 23 and the other end of which engages and supports the slider 15, as shown in FIG. 1.

When the projectile is initially manufactured and assembled, the shaft 21 is rotated into such a position as to arrange the lug 20 out of alignment with slot 19 in stop member 17. Also, the notch 25 in the locking plate 24 is out of alignment with pin 26. This orientation of parts prevents the slider 15 from moving the firing pin into engagement with the primer 14. Thus, the grenade, mortar shell, or other projectile is disarmed and cannot be fired.

In order to arm the mechanism, shaft 21 may be rotated to such a position that pin 26 may enter notch 25 and the lug 20 will be in alignment with the slot 19. This may be done manually before launching or subsequent to launching by a clock mechanism or similar device. With the parts in this position, the grenade or mortar shell, or other projectile may be launched and the impact of the projectile with the target on the lower end thereof (FIG. 1) will cause the slider 15 to move downwardly on shaft 21, compressing spring 28. Thus, the firing mechanism does not detonate primer 14 at the time of impact. After impact, spring 28 expands to move slider 15 along the shaft 21 a distance suificient to engage firing pin 7 with the primer 14 thereby to cause detonation after a certain time period. This time period or delay is determined by such factors as velocity at the time of impact withlthe target and target hardness. Thus, there may be some variation in time delay as between different grenades or mortar shells or other projectiles.

From the foregoing description it will be apparent that the firing mechanism described herein is simple and inexpensive to manufacture. There are no parts which must be manufactured to close tolerances and the assembly of parts requires only a simple manufacturing procedure. The invention provides a firing mechanism which normally may be disarmed and which may be easily armed prior to or subsequent to launching. Thus, there is adequate safety for handling and shipping. Also, the invention provides delay of detonation after impact with the target, whereby the mechanism is especially adapted for hand grenades or other projectiles where it is desired that the projectile bounce before exploding or where it is desired that the projectile penetrate within the target before explosion.

The invention claimed is:

1. A delayed impact firing mechanism comprising a casing, an explosive charge holder in the rear end of said casing for holding an explosive charge and a primer, a locking pin slidably mounted in said holder, a shaft mounted in said casing in alignment with said primer and including a locking disk mounted thereon adjacent said holder and having a notch normally out of alignment with said locking pin and movable into alignment therewith when said shaft is rotated to a certain position, a longitudinal slot in said shaft aligned with said primer, a slider movably mounted on said shaft and having a spacing lug projecting therefrom toward said locking plate, a firing pin mounted in said lug and projecting into said shaft slot and toward said primer, a stop member fixed to said casing between said locking plate and said slider and normally engaging said lug to prevent contact between said firing pin and said primer, said stop member including a slot disposed in a position to receive said lug when said shaft is rotated to align the notch in the locking disk with said locking pin, thereby to permit movement of said firing pin into stabbing contact with said primer, and spring means disposed between the front end of said casing and said slider for permitting spring compressional movement of said slider in response to impact of said casing with a target and delayed return movement of said slider and therewith said firing pin into stabbing engagement with said primer.

2. A delayed impact firing mechanism comprising a casing, an explosive charge holder in the rear end of said casing for holding an explosive charge and a primer, a shaft mounted in said casing in alignment with said primer, a locking mechanism operatively associated with said holder and said shaft for determining an arming position of said shaft, a longitudinal slot in said shaft aligned with said primer, a slider movably mounted on said shaft and having a spacing lug projecting therefrom, a firing pin mounted in said lug and projecting into said shaft slot and toward said primer, a stop member fixed to said casing adjacent to said lug and normally engaging said lug to prevent contact between said firing pin and said primer, said stop member including a slot disposed in a position to receive said lug when said shaft is rotated to said arming position, thereby to permit movement of said firing pin into stabbing contact with said primer, and spring means disposed between the front end of said casing and said slider for permitting spring compressional movement of said slider in response to impact of said casing with a target and delayed return movement of said slider and therewith said firing pin into stabbing engagement with said primer.

3. A delayed impact firing mechanism comprising a casing, an explosive charge holder in the rear end of said casing for holding an explosive charge and a primer, a locking pin slidably mounted in said holder, a shaft mounted in said casing in alignment with said detonator and including a locking disk mounted thereon adjacent said holder and having a notch normally out of alignment with said locking pin and movable into alignment therewith when said shaft is rotated to a certain position, a longitudinal slot in said shaft aligned with said primer, a slider movably mounted on said shaft, a firing pin mounted in said slider and projecting into said shaft slot and toward said primer, means normally effective to prevent contact between said firing pin and said primer except when said shaft is rotated to said arming position, thereby to permit movement of said firing pin into stabbing contact with said primer, and spring means disposed between the front end of said casing and said slider for permitting spring compressional movement of said slider in response to impact of said casing with a target and delayed return movement of said slider and therewith said firing pin into stabbing engagement with said primer.

4. A delayed impact firing mechanism comprising a casing, an explosive charge holder in the rear end of said casing for holding an explosive charge and a primer, a shaft mounted in said casing in alignment with said primer, a locking mechanism operatively associated with said holder and said shaft for determining an arming position of said shaft, a longitudinal slot in said shaft aligned with said primer, a slider movably mounted on said shaft, a firing pin mounted in said slider and projecting into said shaft slot and toward said primer, means normally effective to prevent contact between said firing pin and said primer except when said shaft is rotated to said arming position, thereby to permit movement of said firing pin into stabbing contact with said primer, and spring means disposed between the front end of said casing and said slider for permitting spring compressional movement of said slider in response to impact of said casing with a target and delayed return movement of said slider and therewith said firing pin into stabbing engagement with said primer.

5. A delayed impact firing mechanism comprising a casing, an explosive charge holder in the rear end of said casing for holding an explosive charge and a primer, a shaft mounted in said casing, a slider movably mounted on said shaft, a firing pin mounted in said slider and projecting toward said primer, means normally effective to prevent contact between said firing pin and said primer except when said Shaft is rotated to an arming position, thereby to permit movement of said firing pin into stabbing contact with said primer, and spring means disposed between the front end of said casing and said slider for permitting spring compressional movement of said slider in response to impact of said casing with a target and delayed return movement of said slider and therewith said firing pin into stabbing engagement with said primer.

6. A delayed impact firing mechanism comprising a casing, an explosive charge holder in the rear end of said casing for holding an explosive charge and a primer, a slider movably mounted in said casing, a firing pin mounted in said slider and projecting toward said primer, means normally effective to prevent contact between said firing pin and said primer except when said slider is rotated to an arming position, thereby to permit movement of said firing pin into stabbing contact with said primer, means operable externally of said firing mech- -anism for rotating said slider to an armed position, and

spring means disposed between the front end of said casing and said slider for permitting spring compressional movement of said slider in response to impact of said casing with a target and delayed return movement of said slider and therewith said firing pin into stabbing engagement with said primer,

References Cited in the file of this patent UNITED STATES PATENTS 1,313,930 Taylor Aug. 26, 1919 1,916,244 Woodberry July 4, 1933 2,595,757 Brandt May 6, 1952