US3623432A

US3623432A - Hollow charge projectiles

Info

Publication number: US3623432A
Application number: US851808A
Authority: US
Inventors: Gerhard P L Schminke
Original assignee: Werkzeugmaschinenfabrik Oerlikon Buhrle AG
Current assignee: Rheinmetall Air Defence AG
Priority date: 1969-08-21
Filing date: 1969-08-21
Publication date: 1971-11-30
Anticipated expiration: 1988-11-30

Abstract

A HOLLOW CHARGE PROJECTILE HAVING A PROJECTILE HEAD IN WHICH A CASING IS MOVABLE BETWEEN A POSITION OF REST IN WHICH IT EXTENDS INTO THE INTERIOR OF THE HOLLOW CHARGE AND A WORKING POSITION IN WHICH IT PROTRUDES FROM THE PROJECTILE. A SPRING IS PROVIDED FOR MOVING THE CASING FROM THE POSITION OF REST INTO THE WORKING POSITION. THE SPRING HAS THE SHAPE OF A TRUNCATED CONE WHEREIN THE DIAMETERS OF CONSECUTIVE COILS OF THE SPRING DIFFER BY A LEAST TWICE THE DIAMETER OF THE WIRE. IN THE POSITION OF REST OF THE CASING, THE END OF THE SPRING WITH THE SMALLEST COIL DIAMETER IS DIRECTED TOWARD THE TIP OF A CONICAL CAVITY PROVIDED IN THE HOLLOW CHARGE. THE END OF THE SPRING WITH THE SMALLEST COIL DIAMETER IS FASTENED TO THE CASING AND THE OTHER END OF THE SPRING WITH THE LARGES COIL DIAMETER IS FASTENED TO THE PROJECTILE HEAD.

Description

1971 G. P. L. SCHMINKE HOLLOW CHARGE PROJECTILES Filed Aug. 21, 1969 GERHARD P L. flwm/A/L F fl wwzmwmgll m United States atent 3,623,432 HOLLOW CHARGE PROJECTILES Gerhard P. L. Schrninke, Opfikon, Switzerland, assignor to Werkzeugmaschinenfabrik Oerlikon-Buhrle AG, Zurich, Switzerland Filed Aug. 21, 1969, Ser. No. 851,808 Claims priority, application Switzerland, Aug. 22, 1968, 127,030/68 Int. Cl. F42c /20 US. Cl. 102-56 2 Claims ABSTRACT OF THE DISCLOSURE A hollow charge projectile having a projectile head in which a casing is movable between a position of rest in which it extends into the interior of the hollow charge and a working position in which it protrudes from the projectile. A spring is provided for moving the casing from the position of rest into the working position. The spring has the shape of a truncated cone wherein the diameters of consecutive coils of the spring differ by at least twice the diameter of the wire. In the position of rest of the casing, the end of the spring with the smallest coil diameter is directed toward the tip of a conical cavity provided in the hollow charge. The end of the spring with the smallest coil diameter is fastened to the casing and the other end of the spring with the largest coil diameter is fastened to the projectile head,

The invention relates to a hollow charge projectile, and particularly to a projectile having a projectile head in which a casing is arranged to be movable, which casing has a position of rest in which it extends into the interior of the hollow charge, as well as a working position in which it protrudes from the projectile, with a spring for shifting the casing from the position of rest into the working position.

In a known hollow charge projectile of this type, the casing, arranged coaxially to the axis of the projectile, is surrounded, on the part of it which projects into the interior of the hollow charge, by a cylindrical spring. One end of the spring is fastened to the rear end of the casing, whereas the other end of the spring is fastened to the head of the projectile. In the working position of the casing, the individual coils of the spring butt one against the other, whereas in the position of rest of the casing the spring is tensioned. This arrangement has the following disadvantages. The casing can be moved by the spring out of the interior of the hollow charge only until the coils of the spring butt one against the other. If the casing has to cover a considerable distance from the position of rest into the working position, then a cylindrical spring with comparatively many coils is required for this distance, whereby, in the working position of the casing, a comparatively large part of the casing still projects into the interior of the hollow charge. Furthermore, the hollow charge effect is disturbed by the cylindrical spring and the part of the casing which projects into the interior of the hollow charge.

An object of the invention is to avoid or mitigate the aforesaid disadvantages and to utilise a spring which, with few coils, can move the casing by a comparatively great distance and at the same time is capable of moving the casing as completely as possible out of the interior of the hollow charge.

According to the present invention, there is provided a hollow charge projectile, including a projectile head in which a casing is movable between a position of rest in which it extends into the interior of the hollow charge and a working position in which it protrudes from the projectile, and a spring for moving the casing from the position of rest into the working position, wherein the spring has the shape of a truncated cone, and wherein the diameters of consecutive coils of the spring differ by at least twice the diameter of the wire.

One exemplified embodiment of the invention is described in more detail hereinunder with reference to the attached drawings, in which:

FIG. 1 shows a longitudinal section through the front portion of a hollow charge projectile prior to discharge;

FIG. 2 shows a longitudinal section through the front portion of a hollow charge projectile after discharge.

As shown in FIG. 1, inserted into a cylindrical projectile body 1 is a frusto-conical liner 2, whose tip is directed rearwards into the projectile body 1 coaxially therewith. The projectile body 1 and the liner 2 form an annular space, in which a hollow charge 3 consisting of explosive is contained. The projectile body 1 has a shoulder 4 on its inside. The part 5, lying in front of the shoulder 4, of the projectile body 1 is thinner-walled than the remaining part 6. A ring 7 is braced on the shoulder 4. The ring 7 is fastened to the part 6 of the projectile body 1 by a flanged rim of the part '5. The ring 7 has a rim 8 which serves for the centering of the liner 2. A rear front surface 9, perpendicular to the projectile axis, of the ring 7 forms a stop for the liner 2.

The projectile body 1 is terminated in front by a cover 10, designed as a projectile head, which is fastened to the ring 7 by an annular extension piece 11. The cover 10 has a central bore-hole 12, whose axis coincides with the projectile axis. A casing 13 is mounted to be movable in this bore-hole 12. Fastened to this casing is a second casing 14 projecting into the liner 2. The front section of the casing 14 contains a detonator 15. Present on the inner wall of the casing 14 is a ring-shaped shoulder 16, against which a front face of the detonator 15 butts. In addition, the casing 13 has an inwardly projecting shoulder 17, against which a thin sheet disc 18 is pressed by the forward front face of the casing 14.

A firing pin 19, which has a shaft 20 and a firing pin head 31, is guided movably in the casing 13. The shaft 26 of the firing pin 19 is braced on the sheet disc 18. The tip of the firing pin 19 extends through the sheet disc 18 into the casing 14 and is in front of the detonator 15. The shaft 20 of the firing pin 19 butts, in the position shown, against an inwardly projecting annular shoulder 21 of the casing 13. This shoulder 21 prevents the firing pin 19 from being able to fall in front out of the cover 10. The outer side of the casing 13 has a groove of V-shaped cross section which extends in the peripheral direction. In the cover 10 there is a bore-hole 23 which is directed transversely to the projectile axis and in which a safety bolt 24 is shiftably mounted. This safety bolt 24 has a conical tip which butts against a wall 30 in the groove 22 of the casing 13. The end 25, opposite to the tip, of the safety bolt 24 butts against a wall 26 forming a guide for the projectile.

One end of a draw spring 28, having the shape of a truncated cone, with the largest coil diameter is fastened in a slot 27 on the inside of the cover extension piece 11, and the other end of the spring 28 with the smallest coil diameter is fastened to a flange 29 of the casing 14. The diameters of the consecutive coils of the spring 28 differ by at least twice the diameter of the wire. The end of the spring with the smallest coil diameter projects towards the tip of the conical cavity of the hollow charge 3 when the casing 14 is in its position of rest, and in the working position of the casing 14 this end projects in the opposite direction. The coils of the spring 28 in the working position of the casing 14 lie practically in one plane.

The method of operation is as follows:

After the projectile has moved away from the wall 26, the safety bolt 24 is no longer held back. The bolt 24 is therefore driven out from the groove 22 by the force, acting on the

casings

13, 14, of the spring 28, which force is transmitted to the bolts head by the wall 30 of the groove 22. By this means, the

casings

13, 14 containing the firing pin 19 and the detonator 15 are released and shifted by the spring 28 forward through the cover bore-hole 12 into the position shown in FIG. 2. Upon this movement, the coils of the spring 28 fit into each other, i.e telescope, so that finally they lie substantially in one plane and the rear end of the casing 14 can move as far as the stop of the cover 10.

The air pressure head acting on the firing pin head 31 is not sufiicient to punch through the sheet disc 18. However, upon impact in the target, the firing pin 19 is driven backwards into the detonator 15, and the hollow charge 3 is exploded in known manner by means of the detonator 15 and a further detonator (not shown in the drawing).

I claim:

1. A projectile with a conical hollow space having a hollow charge, comprising a projectile head, a casing in said projectile head movable from a position of rest wherein said casing extends into said hollow charge to a working position wherein said casing protrudes from said projectile head, a truncated cone-shaped spring having a plurality of consecutive coils of different diameters wherein the diameters of said consecutive coils differ by at least twice the diameter of the wire forming said coils,

said spring being fastened at the end With the smallest coil diameter onto said casing and at the end With the largest coil diameter onto said projectile head to urge said casing from the position of rest into said working position so that said spring is reversed whereby in the working position of said casing the end with the small coil diameter points in the opposite direction from that in the position of rest of said casing.

2. A projectile as set forth in claim 1 wherein said spring is reversed upon moving said casing to working position and the coils of said spring are substantially located in one plane.

References Cited UNITED STATES PATENTS 1,229,669 6/1917 Stuart 102-79 2,717,552 9/1955 Brandt 10256 2,737,118 3/1956 Peck 102-79 3,3803 84 4/1968 Kaiser et a1 102-71 VERLIN R. PENDEGRASS, Primary Examiner US. Cl. X.R. 10276