US2850974A

US2850974A - Hydrostatic fuze

Info

Publication number: US2850974A
Application number: US542450A
Authority: US
Inventors: Abreu Jose Menay Vieyra De
Original assignee: Individual
Current assignee: Individual
Priority date: 1954-11-10
Filing date: 1955-10-24
Publication date: 1958-09-09
Anticipated expiration: 1975-09-09
Also published as: FR1138915A; DE1057501B

Description

Sept. 9, 1958 J. MENA Y vlEYRA DE ABREU 2,850,974

HYDROSTATIC FUZE v Filed Oct. 24, 1955 Sheets-Sheet 1 INVENTOR Tos: MENA y `Vrr- YRA ne AeReu ATTORNeYs sept. 9, 195s J. MENA Y vlEYRA DE ABREU HYDRo'sTATIc FuzE 2 Sheets-Sheet 2 Filed Oct. 24. 1955 2,850,974 i'yatented Sept. 9, 1958 HYDROSTAHC FUZE Jos Mena y Vieyra de Abreu, Madrid, Spain Application October 24, 1955, Serial No. 542,450

f Claims priority, application Spain November 10, 1954 7 Claims. (Cl. 102-7) VThe present invention relates to a new fuze applicable to underwater projectiles and particularly to depth charges for use against submarines.

This fuze will ensure an underwater explosion of the projectile or the depth charge, with such precision as to the calculated depth, that its absolute and relative errors are technically insignificant.

The mechanisms thereof operate in combination with a` normal hydrostatic pressure. Provision is made to prevent detonation due to an abrupt excess of pressure, so that the explosion of other mines exercise no effect on their correct performance.

Furthermore, provision has been made to block all mechanisms in order to prevent their performance until the charge has reached a predetermined depth of, for example meters, thereby avoiding all risks to any craft launching such devices.

The novel fuze is likewise provided with all safety devices required of this kind of projectile, both for their storage as also for the transport and manipulation thereof.

These safety devices by no means interfere with the perfect performance of the apparatus and are achieved by a very reduced number of prociently arranged elements, whereby within a few seconds, the entire mechanism can be removed from the depth charge for an inspection thereof.

The desired depth can be set instantaneously, or changed at will, either to increase or reduce the depth of explosion. Said regulation of depth can be performed within a few seconds and set as often as required.

It will be understood that with this device, technically, there is no need to limit the maximum depth of explosion, as all elements can operate at any depth. In practice, its use is generally confined to the maximum depth apt to be reached by a submarine.

Moreover, absolute .watertightness has been provided for, thereby preventing deterioration of the mechanism and explosive charge.

For a better comprehension of the invention, the accompanying drawings represent, in:

Fig. 1, a longitudinal section of the fuze;

Fig. 2 shows a perspective view of the depth setting and indicator device;

Fig. 3 shows the spring compressor element;

Fig. 4 shows a perspective view of the uted sleeve;

Fig. 5 shows a development of the lower portion of the compressor element shown in Fig. 3;

Fig. 6 shows a partial view of the sleeve which externally sheathes that portion of the fuse showing the depth marked by the indicator;

Fig. 7 shows a plan view of the graduated index disc;

Fig. 8 shows a sectional view of the safety device between the primer and the booster; and

Fig. 9 shows a sectional view of the device shown in Fig. 8 at the time the fuze operates.

The fuze body 22, Fig. l, is constituted by a cylindrical element the upper portion of which has an externally threaded central shank 22a to which is screwed a depth regulator. Underneath the depth regulator is a circular flange 22b for the accommodation of a dual setting disc 12 and on which is a threaded ring 22C to which is threaded a cap 1. The fuze body is threaded at 22d to hold the fuze in the projectile casing. The llange 2211 is turned by a wrench the teeth of which engage with several holes 22e. Between the flange and the projectile casing may be placed a resilient gasket of rubber or other appropriate material for insuring a watertight joint. Within the fuze body 1 is an axial cylindrical bore 22f within which is slidably mounted a tube 5. The bore 22j is enlarged within the shank 22a to accommodate locking balls 36 which are set in holes in the end of tube 5.

An expansion chamber 42 is provided within fuze body 22 and is closed by a gasket 43 which is held in place by a washer 44.

A cylindrical casing 23 is threaded to the end of fuze body 22, and within the lower end of the cylindrical casing 23 is threaded a fluted tube 45 having flutes 16 on the outside thereof. At the end of the fluted tube 45 within the cylindrical casing 23 is a groove 46.

Attached to the tube 5 is a sleeve 4, which extends within the cylindrical casing 23 and the end of which surrounds the grooved end of uted tube 45. The sleeve 4 together with the tube 5 forms a spring compressor element. On the inside of the end of sleeve 4 surrounding the uted tube 45 are two wedges 15 which project into the groove 46.

Sleeve 4 has a plurality of apertures in the wall thereof which are spaced both circumferentially and axially from each other along the entire length of the sleeve. In the embodiment shown, two sets of apertures are provided, one aperture in each set having a diametrically opposed aperture in the other set.

Within the end of the fluted tube 45 is slidably fitted a primer piston 19, in the upper end of which is a pair of diametrically opposed slots 18a. Fluted tube 4S has a pair of diametrically opposed apertures 46a in the end thereof within the sleeve 4, and positioned within these apertures are locking detent balls 18 which project into the grooves 18a on the primer piston 19. On the end of the primer piston 19 is a primer casing 20 within which is a primer 21 and a detonator cap 7.

A spring 6 is provided between the end of the sleeve 4 attached to the tube 5 and the primer piston 19. In the position of the parts shown in Fig. l, the spring is unstressed.

Threaded into the end of the fluted tube 45 where it is attached to the cylindrical casing 23 is a cap 39 within which is a safety device to be described below. Threaded into the cap 39 is a booster casing 27 containing a booster charge 26 having an axial bore 26a therein. Within the axial bore 26a is a ring pin 8 which is pointed toward the primer 21.

The depth setting device comprises an inner adjusting member 11 which is threaded over the shank 22a and which has the tube 5 projecting therethrough. At the point where the tube 5 passes through the inner adjusting member 11, the outside diameter of the tube 5 is reduced so that when inner adjusting member 11 is screwed onto the shank, tube 5 will be moved into the fuze body 22.

Over the inner adjusting member is a cover member 9 which is rotatably mounted on the inner adjusting member 11, and which has depending therefrom dual pointers 10 which extend downwardly to the fuze setting disc 12. Through the cover member 9 is a diametrical bore 13a, and in the end of the tube 5 are two apertures 14 which may be aligned with the bore 13a. A safety pin 13 may be inserted through the bore 13a and the apertures 14, and held therein by the arm 13b.

In the cap 1 are two Valves 29 each consisting of a housing 2, 3 having an aperture 30 on the inner end thereof, and having a spring loaded plug 31 therein which is spring loaded outwardly by spring 32.

Within the ,upper end of tube ,5 is a gland 33. Adjacent the lower end of gland 33 are a plurality of grooves 35 in the tube 5. Gland 33 has a transverse bore therethrough within which are mounted spring ,loaded :balls 34 which are spring loaded outwardly Aand which :normall-y engage in 'one -of the grooves 35.

.In -the ,cap '39 threaded into the lower end of iluted tube 45 is aztransverse passage 28a within which are ytwo rollers 28 held in place yby spring loaded balls 38 .engaging in a groove l40 yalong the wall of lpassage 23a. The rollers 28 are normally in contact with each other as shown in Fig. 8.

In the lwall fof Ythe `cylindrical casing 23 adjacent the end-of sleeve 4 is an opening 24, and depth setting corresponding to the settings on the fuze setting vdisc '12 are printed 'on the end of sleeve 4 on a level with the opening 24.

The number of spaces between the utes V-16 Alon'fluted tube 19 is one greater than the ynumber oftpairs of Aopposed apertures 17. The spacingof the y'flutings is such that the spaces between them are vertically aligned with the apertures `17 'in the sleeve 4.

As the hydrostatic pressure yoperates upon the com-V pressor `

element

4, 5, it is caused to descend, Icompressing the spring 6, which thus accumulates sufficient force :to re the Vprimer 7, which upon Vstriking the firing pin y8, produces the explosion. 'The ldepth at which lthis detonation is to `be produced, is set by Vmeans lof `the depth setting device. ABy the rotation of said pointers -1'0'to 'mark the desired depth on the graduated disc, the

compressor element

4, 5 is also caused to rotate, as pin 13 'engages the tube 5 andthe casing9, thus placing the vtwo internal wedges at the lower end of the lcompressor element so that they Vwill register with the entrance of` two ofthe flutes on the tinted sleeve `45. This will cause .the compressor element to descend Ain the axial direction b y the sliding action of said wedges in the referredk toutes or channels.

The locking `detent balls 18 provided in the `openings in the upper portion of the fixed fluted sleeve 4'5prevent a descent of the primer piston '19 until they escape. The spaces between flutes `16` in the fluted sleeve 45 are arranged in such la manner that the balls 18 will register with that pair of openings '17 that has been aligned therewith by the fuse setting device, which openings lare placed at a 'higher position in the sleeve 4 the greater the `depth at which the detonation of the charge is required.

'To set the explosion depth, the cap 1 is removed temporarily in order to rotate the cover member 9 on .the depth setting device `in the desired direction so that the two pointers 1t! thereof will coincide on the graduated disc 12, with the desired detonation depth. While maintaining -said cover member 9 in .this position, the internal element 11 of the depth setting device is screwed down, whereby the compressor element is immobilized, since the two wedges 15, which .heretofore rotated freely inthe slot 46, see Figs. ,l and 4, will have entered two channels on sleeve 45.

Thereafter, by removing ytherpin 13 and replacing the cap 1, the fuse is prepared to operate underthe influence of hydrostatic pressure.

After Ahaving set the depth at which the explosion ris to occur, the charge is ready for launching. As the charge enters the water, the hydrostatic pressure is increased, thereby opening the valves v31, so Athat the water will fill the interior of the cap 1 and penetrate through the bores previously occupied by the `pin 13 to the -tubular sleeve 5 where it will meet with Vthe resistance of the gland 33 that closes said tube.

Assoon as thecharge Areaches eight or ten meters, but not before, the water pressure will be able t-o -push `said gland 33 inwards to overcome the predetermined `resistance of the two-spring loaded balls 34 against fthe `inner walls :of =the ltubular sleeve -5 in -which successive ldetention slots 35 are provided. By -this safety feature, the

mechanisms are kept blocked, preventing their performance, while the charge reaches a minimum depth of eight or ten meters, or any other predetermined depth, so that under no conditions the charge can explode in the proximity of the launching craft.

While the gland 33 occupies the position shown in the drawing, or with the two balls 34 held in any of the successive slots 35, Vthe tube y5 cannot descend, the balls 36, lodged in the walls of said shank being pushed outwardly :by the `gland 33 land protruding a `suiicient distance into .slots -47 to prevent the descent.

After the water has pushed the gland 33 to the bottom of thetube- 5 the -balls 36 wil-l offer no further resistance, as they will now fall into tube 5.

By the progressive advance of the compressor element, the spring 6 will be compressed until the two bores 17 situated vertically above the two balls 18 register therewith, at which moment the balls 18 escape. :Piston 19 is then free and yis then impelleddownward by lthe spring. At this moment, the primer tube 20, "forming ,a conical wedge, will penetrate bet-Ween the rollers 28, `see Fg..8, and ythus advance until the primer ,strikes against `the point 'of 'the lfiring pin l8, see Fig. 9, -thereby causing an explosion in the very center of the booster 26.

The two -rollers 28, see Figs. -8 and =9, placed in lparallel and "in 'contact with each other, serve as a-safety device to 4break the shock wave, liable to be produced by an untimely explosion 'of the primer 7. Fig. -8 shows 'the position lof said rollers 28 prior to their separation by the conical lpoint Aof the primer tube 20, and Fig. Y9 shows said rollersv after their separation, thus permitting the'passage of the primer `tube 20'toward the firing-pins. The rollers 28 lare held in contact by la Vslight Vpressure of the spring 37, whichcompresses the balls 38 against the walls of the lower plug 39, which is in turn `providedgwith slight cavities 40 on the internal walls thereof.

The pin 13, which transmits the rotation Iof the indicator 9 to the tube 5, likewise constitutes asafety-device, since .while it is xedin its normal position it will prevent a descent of the compressor element, the upper end of whichis traversed by the pin 12 which has to beremoved before the device will operate. The flutes 16 tend to keep the balls 18 aligned with the'V selected pair of bores 17 for each depth. However, there is a pair of .flutes that do not coincide with `any pair of bores, so that by placing the indices '10 on the cap 9v of depth setting device 411 in the position marked with the thick line 41, the fuze cannot operate, since the wedges 15 register precisely with the onlyvpair of flutes `1`6 that do not permit balls18 to coincide with anyof the 'bores 17.'

If a small amount of Watershould penetrate between the compressor element and the fuze body '22, a cavity 42 has been provided wherein it -will'be retained `by means of Ia resilient gasket 43, which is compressed 'by the threaded washer 44.

If, after the charge hasY been launched, an abrupt excess of pressure should occur, for example, from another mine or depth charge, the plugs 31 inthe valves 29 would then descend to the bottom overcoming the resistance of their springs 32, .and thus closing the bores 30 andpreventing :the passage of water pressure into the fuze.

l. A hydrostatic fuze for use in underwater explosive devices comprisinga fuze body engageablejn lthe explosive device and -having an axial bore therethrough, a ,cylindrical casing attached to one .end .of said -fuze body, a spring compressor element having a tube slidable in ysaid bore and a sleeve fixed to the endof said` tube within said cylindrical casing, said sleeve having aplurality of apertures in the wall thereof spaced circumferentially and axially of said sleeve from keach other, a wedge on the end of said sleeve opposite said tube projecting radially into said sleeve, a utedftube attached within .the end of said cylindrical casing opposite said fuze body and `extending within the Vend `of saidsleeve, said .fluted tube havingwa groove around the outside of the end thereof within said sleeve into which said wedges project, each of the utings being vertically aligned with one of said apertures in said sleeve, a detent locking ball in the end of the wall of said n uted tube within said sleeve, a primer piston slidable Within said iluted tube having a groove therein in which said locking detent ball is engaged, a spring between said primer piston and said sleeve normally in the unstressed Condition, a primer on the end of said primer piston opposite said spring, a booster having an axial bore therein attached on the end of said cylindrical casing with the bore aligned with said primer, a firing pin in said bore, means between said primer piston and said booster for blocking a shock from the explosion of said primer and for permitting passage of said primer, depth setting means on the end of said tube opposite said sleeve for rotating said tube and said sleeve and for urging said tube and sleeve toward said primer piston, gland means held in the end of said tube adjacent said depth setting means for keeping water pressure from within said tube until a predetermined pressure has been reached, and a cap over said depth setting means having a valve therein for admitting water to said fuze. j

2. A hydrostatic fuze as claimed in claim 1 in which said means between said primer piston and said booster comprise a pair of spring loaded rollers in contact with each other, a plug in the end of said uted tube having openings therein in which said rollers are movable, and the end of said primer being beveled.

3. A hydrostatic fuze as claimed in claim 1 in which said depth setting means comprising an inner adjusting member threaded to said fuze body, a cover member rotatably mounted on said inner adjusting member and having pointer means thereon and a bore therethrough, said tube having apertures therein in alignment with said bore, and a pin through said bore and apertures.

4. A hydrostatic fuze as claimed in claim 1 in which l said gland means comprise a gland slidably tted in the interior of'said tube having a groove therein, and a spring 6 loaded locking ballin said opening in said gland and projecting into said groove.

5. A hydrostatic fuze as claimed in claim l in which all but one of the flutings on said fluted tube are aligned with one of said apertures in the wall of said sleeve.

6. A hydrostatic fuze as claimed in claim 1 in which said valves in said lcap having a spring loaded plug therein are spring loaded outwardly, and yhave an aperture beneath said plug, whereby a sudden hydrostatic pressure causes the plug to overcome the spring loading and close said aperture.

7. In a hydrostatic fuze for use in underwater explosive devices having a fuze body engageable in the explosive device and having `an axial more therethrough, the combination of a cylindrical casing attached to one end of said fuze body, a spring compressor element having a tube slidable in said bore and a sleeve fixed to the end of said tube Within said cylindrical casing, said sleeve having a plurality of apertures in the wall thereof spaced circumferentially and axially of said sleeve from each other, wedges on the end of said sleeve opposite said tube projecting radially into said sleeve, a iluted tube attached within the end of said cylindrical casing opposite said fuze body and extending within the end of said sleeve, said fluted tube having a groove around the outside of the end thereof within said sleeve into which said Wedges project, each of the flutings being vertically aligned with one of said apertures in said sleeve, a detent locking ball in the end of the wall of said fluted tube within said sleeve, a primer piston slidable within said fluted tube having a groove therein in which said locking detent ball is engaged, and a spring between said primer piston and said sleeve normally in the unstressed condition.

References Cited in the file of this patent UNITED STATES PATENTS 1,514,743 Taylor Nov. 11, 1924 FOREIGN PATENTS 165,108 Great Britain June 3o, 1921