US2763212A

US2763212A - Selective time-impact fuze for hand grenades

Info

Publication number: US2763212A
Application number: US140291A
Authority: US
Inventors: James F Mccaslin
Original assignee: Individual
Current assignee: Individual
Priority date: 1950-01-24
Filing date: 1950-01-24
Publication date: 1956-09-18
Anticipated expiration: 1973-09-18

Description

Sept. 18, 1956 J. F. MocAsLlN SELECTIVE TIME-IMPACT FUZE FOR HAND GRENADES Filed Jan. 24. 195o lthe-following description and accompanying SELECTIVE TIME-IMPACT FUZE FOR HAND GRENADES James F. McCaslin, Alexandria, Va. Application January o. '140,291 i 8 claims. (ci. 1oz-rz) (Granted under Title 35, U. S. Code (1952), sec. 266) The invention described herein may be manufactured and used by or for the Government, for governmental purposes, without the payment Ito me of any royalties Ithereon.- e' j This .invention relates lto fuzes and-more specifically to a time-impact fuze for hand grenades or `the like.- Y

It has 'been found lthat hand grenades employing the all-ways type ofy fuze have proven extremely dangerous to the using personnel in that the-fuze armed and tired too quickly while still in effective proximity of the thrower. The selective--time-impactffuze yof this invention utilizesthe 4-all-ways type of fuze in combination with a Vdetent means which provides a suficient delay -to allow the grenade to reach -a safe dis-tance from they thrower before the fuze becomes armed -for impacty tiring. There lis also incorporated in the fuze a selective means enabling thethrower to select either a powder delay `train or the combination of powder delay train and the, all-ways impact fuze. Another novel feature of the tuze of this invention is the provision of vents within 'the fuze body for receiving any smoke `or sparks and conning them within the body.

The specific nature of the invention as well asl other objects and advantages thereof will clearly appear from drawings in which: n

Figure l is a )sectional view of lthe lfuzemounted in the cap of al hand grenade.

Figure 2 is a view taken along line2-2 of yFigurel;`

Figure 3 is a view taken along line 3-3 Aof Figure 1.

Figure 4 is a plan view of `the :fuse housing with its yclosure removed and showing' the internal vents.

Figure 5 is Va `fragmentary sectional view of a m'odied all-ways fuze positioned in -the all-ways fuze cavity of the lselective time-impact fuze. e A

Referring now to the drawings by characters of reference there is shown in Figure l an embodiment of my invention wherein 1 generally indicates the Ibody of a hand grenade having a die cast cap 2 threadedly receiving, as indicated by reference numeral 3, a bouchon 4 having mounted thereon an operating lever 5 extending across its vtop and down the side of the grenade body. The bouchon 4 is formed with a recess 6 in its Itop providing two upstanding walls 7 and 8. A pin 9 supportedjby the walls carries a spring engaging a striker 11 rfor striking a primer cap 12 positioned in ythe bot-tom of -the recessV 6 when the operating lever 5 has been released by the thrower. rPhe lever 5 and striker 11 are held inoperative by means of a safety pin 13 positioned in the vertical walls 6a and 6b of the lever 5 and thewalls 7 and` 8 of the bouchon, as best seen in Figure 2, until such time as-it is desired to use rthe grenade whereupon thesafety pin is withdrawn, while 'theV throwers Ihand holds the downwardly projection portion of Ithe lever and body. The bouchon has a bottom recess 14 wherein is keyed,f as

a-t 15, a housing v1'6 havingfa closure 17. Fixed Vin the lowr Portion vlef' the hltsilefl Meer@ lahaine a relayn 18a x'ed therein. An opening-19 in thev lower l nited States Patent V(Y portion forms a ash passage between the 'primer detonat-or 20a of jthe all-ways fuze 20-in ythe

cavity 21of'the housingassembly

16 and 17 and `the relay 18a. The relay 18a is'also' in communication'with the primer cap 12 .by means of 'a power time train 12d'whi'ch extendsy through the housing 16 and bouchon 4. The `all-ways fuze 20 comprises a sleeve 22 housing a -ring pin 23 slidable therein. The sleeve`2r2 has a primer detonator. 20a ixed"in one e'nd in"line`withand opposite'the opening. 19?'I The" tiring" pin has at'raves'e bore 24' adjacent itsA fear endwithin which are retained ltwo balls 25 and I 26 kept in spaced lrelationship by an arming pin 241havprick end of said ring pin is` resiliently spaced from theV prime-r detonator a by means of a helical spring 23a.-

ing its shank normally slidably positioned. inthe bore 30 of vthe closure 17 Vland `avbor"e29 in thefrealportion of said pin and intersecting the traverse' bore "24." The The shank of the arming pin 27 has a necked section 31 adjacent its end in the tiring pin and a flanged topA 32 in engagement with a combustible detent 32a. A helical spring 33 about the 'shank Vandbetween the `flange top 32 and a base 30a in the bore 30 maintains contact between th-e anged top 4and a combustible detent 32a. The com'bustible detent releasably maintains-the arming 'pin inthe bores 29 and 30 when the fuzeisY set forl impact firing. The cavity 21` has a-domeshaped top,V wall'Zla so ythat when the arming pin has released the all-ways jfuze, the firing pin will be cam-med toward the primer detonator should the side of the grenade strike ythe target. arming pin is ejected from the tiring pin into `the cavity 4a of the bouchon and the ball.25 and.26 rolled toward the longitudinal axis lof the iiring'pito permit thering pinto slide in the sleeve 22 and strike the primer detonator upon impact. The combustible detent 32a covers the bore 30 in contact with the hanged end of the tiring pin and is retained in the position by the bottom face of the bouchon. At yone edge the detent is in contact with a black powder igniter pellet 34 in a recess 34a of the closure 17. A short time delay train 35 located arming pin. The opposite end of :the shaft extends out-V wardly of the bouchon and has fixed lthereto an arm 4 0 perforated at its free end 'as at 41 and receiving the,

safety pin 13. The housing 16 has formed therein radially spaced chambers 42 for receiving and storing smoke and sparks of the combustible elements of the fuze to prevent the same escaping to the atmosphere and lthereby warning lthe enemy. The chambers also contain sufficient oxygenfor normal combustion of the combustible elements and provide a sufficiently large expansion chamber to prevent excessive pressure build up. The chambers are in com-` munication with each other by means of a channel 43 formed in the bottom of housing recess 17a. The cavity 21 is in communication with the chambers 42 by'means of a4 duct 44 connecting the cavity 21 with one of said chambers. The recess 4a in the bouchon isin communication with channel 43 and the said chambers by means of a duct 45 in the bouchon aligned with a duct 46 in the closure member.

In `operation the grenade is held in the hand of the thrower with the ngers embracing lthe grenade body andl lever.v y The safety pinis pulled andthe .grenade thrown releasing the lever which iesolf allowing the striker lto re the primer cap. The primer cap ignites thedel'ay train, 12a whichgburnsjto functionyythe boosterL When the combustible detent functions, the ,e

c 3 Y t simultaneously ignites the short time delay train which ignites the black powder igniter pellet which in turn ignites the combustiblejdetent. The short time delay and the .combustible detent burn with suicient delay to allow the grenade `to reach a `saie distance fromthe thrower and then permits'the arming pin to be forced up into'the cavity 4a of `the bouchon by action of the rspring under the iianged head of the arming pin, thus arming they all-ways fuze mechanism for functioning under impact. The tiring pin moves down in the sleeve containing the primer detonator to strike the said detonator if the' lbottom of the grenade strikes' the target. It the grenade strikes `the target on its fuze, the primer detonator moves towards the tiring pin, and if the grenade strikes the target at any angle to the verticalL axis of the grenade the firing pinv is cammed into the primer detonator kas the rounded end of the tiring pin moves along the dome shaped top of the cavity 2. T he selector held in position bythe-safety pin through the selector arm, dogs the aliways fuze arming pin, and in that' position the grenade is functioned by the time'delay train 12a only. if, after pulling the'safety pin and while the grenade is still gripped in the hand, the selector is moved 90 in a counterclockwise direction the arming pin is free to move into the cavity 4a upon the burning of the conibustiblc detent. As a further safety against' the firing of the all-ways fuze by centrifugal means due to excessive spin from a snap of the wr-ist in throwing, the arming pin is necked so as to be caught at `the edge of the arming -pin perforation inthe dome, due to any excessive off axis pressure on the all-ways fuze assembly, thus preventing thefull arming of the impact mechanism until the effect of spin is dissipated, but upon such dissipation still allowing normal arming and subsequent impact 'functioning. i

In Figure 5 there is shown a modified all-ways fuze, generally indicated by the reference character 50positioned in the cavity 21 of the liousingassembly

members

16 and 17. The modiiied all-ways fune comprises a sleeve 51 having a primer detonator 52 fixed in one end and in communication with the ash passage 19. The opposite end of sleeve 51 is provided with an inwardly directed bevel 53. Slidably positioned in the sleeve 51 is a sleeve 54, its longitudinal perforation receiving an arming pin 27, The sleeve 54 is longitudinally slotted, as indicated by the reference numeral 55, to receive the firing pin S7. Adjacent the primer detonator is a helical spring 56 in the sleeve 51 which resiliently supports the firing pin 57 stamped from sheet metal. The spring 55 also resilien-tly spaces the

sleeve members

51 and 54 in the cavity 21. The liring pin is formed with a prick point S8 at the end adjacent the primer detonator and oppositely directed arm's 59 and 60 in contact with spring 56. The body 61 .and `the circular head 62 are slidably positioned in the slot 55 aud normally held diagonally of the vertical axis of the fuze by the arming pin 27 which has one end in contact with the head 62. The arm 60 is always in contact with the vbottom of sleeve 54. In operation the arming pin is ejected from the sleeve 54 and the arm 60 is pivoted about the bottom of sleeve 54 due to the action of spring S6 causing the body and head to move through the slot 55 and align the prick point with the primer detonator. Upon impact either the primer detonator carried `by sleeve 51 moves toward the tiring pin or the tiring pin carried by sleeve 54 moves toward the primer detonator.

l claim:

l. ln a hand grenade employing a pivotally supported and spring urged primer striker means normally held in safe position by means of a safety pin which is withdrawn prior to throwing the genade, a selective time-impact fuse compris-ing a bouchon threadedly rlixed .to `'the cap of said grenade and supporting said striker means in a recess formed in its top, a primer iixed in said recess in cooperative relationship with said striker means, said bouchon having a downwardly directed cavity for receiving an arming pin of an all-ways fuze, a depending housing in the base of said bouchon and directed 'inwardly of said cap, said housing being provided with a cavity having truncated walls and a dome shaped top wall, an all-ways fuze positionedinsaid cavity, a perforationin said dome shaped top wall in alignment with said downwardly directed cavity and said all-Ways fuze, anL allways fuze yspring loaded' arming pin positioned partially in said all-ways fuze andr partially in said perroration, a

v combustible detent positioned across the open end of said perforation'and in engagement with said arming pin, a black powder pellet iixed adjacent one edge of said dc- `tent, a rst delay powder train through said bouchon and said housing and spaced from said cavity, said first delay powder train connecting said primer `with said booster for time delay functioning Aof said grenade, a second delay powder train of relative short burning period in said bouchon, said second delay powder train connecting said primer and said black powder pellet to ignite said combustible detent for impact tiring of 'said grenade.

2. The time-impact fukze of claim l wherein said bouchon is provided with a radial bore, a selective timeimpact means rotatably mounted in said bore, said meansv safety pin, said arm manually movable upon withdrawal of said safety to rotate said shaft to move the finger out of alignmentwith said arming pin'providing an unobstructed path of travel for the arming pin when said pin is released by the combustible detent to arm said grenade for impact firing.

3. Thevtime-impact fuze of claim 2 wherein said fuze is provided with smoke and spark concealment means comprising radially spaced chambers in said housing, channel means interconnecting said chambers, a first duct passing through said bouchon and said housing member having one end in communication with said downwardly directed cavity and said perforation, the opposite end of said tirst duct in communication with said channel, a second duct located in said housing, said second duct having one end in communication with said cavity containing the all-ways fuze and its opposite end in communication with one of said chambers, said ducts receiving and directing smoke and sparks formed by the combustible elements to said chambers.

4. The time-impact fuze of claim 3 wherein said fuze is provided with safety means to prevent premature functioning of the all-ways fuze due to centrifugal force created by excessive spin when the grenade is thrown, said safety means comprising a tapered neck formed in said arming pin adjacent the end normally positioned in said all-ways fuze, said neck engaging the edge of the perforation in the dome after the pin has been released by the combustible detent, said neck disengaging said edge after the spin of the grenade has been sufficiently reduced, said pin entering the downwardly directed cavity to release the all-ways fuze for impact functioning.

5. In a hand grenade a time-impact fuze comprising a bouchon threadedly engaged to the cap of the body of said grenade and supporting a spring urged striker means normally held in safe position by a safety pin which is withdrawn prior to throwing the grenade, said striker means releasable upon throwing said grenade to fire a primer fixed in said bouchon and extending into said cap, a booster lixed in said housing, a iirst firing delay train communicating said primer with said booster for time delay tiring, a combustible detent in said housing, a second firing delay train of shorter burning period than said first train and communicating said primer with "said combustible detent, an all ways fuze in said housing hav-` ing an arming pin in operable relationship with said detent, selector means comprising a shaft rotatably mounted in said bouchon and held against longitudinal movement, said shaft having a nger extending from one end substantially across said detent and in the path of said arming pin, the opposite end of said shaft provided with an arm normally in engagement with said safety pin, said arm movable upon withdrawal of said safety pin to rotate said shaft to move the finger out of alignment with said arming pin when said pin is released by the combustible detent to arm said grenade for impact firing. Y

6. In a hand grenade a time-impact fuse comprising a bouchon threadedly engaged to the cap of the body of said grenade and supporting a spring biased striker normally held in a safe position by a pin adapted to be withdrawn prior to throwing the grenade, said striker releasable to lire a primer xed in said bouchon and extending into said cap, a booster fixed in said body, a lirst firing delay train communicating said primer with said booster for time delay firing, a combustible detent in said body, a second firing delay train of shorter burning period than said rst train and communicating said primer with said combustible detent, an all-ways fuse in a cavity formed in said body and having an arming pin in operable relationship with said detent and means for selectively rendering said all-ways fuse operable to arm said grenade for impact firing.

7. The time-impact fuse of claim 6 wherein said body is provided with interconnecting chambers communicating with the said all-ways fuse cavity and being entirely within said fuse, said chambers containing sucient oxygen for normal combustion of said tiring delay trains and providing a volume to prevent excessive pressure build up and to receive and store the products of combustion.

8. The time-impact fuse of claim 6 wherein said means for selectively rendering said all-ways fuse operable comprises a shaft rotatably mounted in said bouchon and held against longitudinal movement, said shaft having a ringer extending from one end substantially across said detent and in the path of said arming pin, the opposite end of said shaft provided with an arm normally in engagement with said safety pin, said arm movable upon withdrawl of said safety pin to rotate said shaft to move the linger out of alignment with said arming pin.

References Cited in the le of this patent UNITED STATES PATENTS 1,517,810 Wiley Dec. 2, 1924 1,537,208 Wiley May 12, 1925 1,768,678 Froelich July 1, 1930 2,005,053 Schlafer June 18, 1935 2,412,636 Short Dec. 17, 1946