US3437289A

US3437289A - Miniature rocket nozzle

Info

Publication number: US3437289A
Application number: US660856A
Authority: US
Inventors: Arthur T Biehl; Robert Mainhardt
Original assignee: MBAssociates Corp
Current assignee: MBAssociates Corp
Priority date: 1966-04-04
Filing date: 1967-07-13
Publication date: 1969-04-08
Anticipated expiration: 1986-04-08
Also published as: US3345902A; US3490121A

Description

April 8, 1969 1', 'BlEHL ET 'AL 3,437,289

7 MINIATURE aocxm NOZZLE Original Filed April 4, 1966 KIKKK'"? I. 4

ARTHUR T. BIEHL .ROBERTMAHARDT US. Cl. 244--3.23 2 Claims ABSTRACT OF THE DISCLOSURE The invention relates to miniature rockets provided with propellant means arranged to be ignited by a primer cap positioned within a cavity of an integrated preformed nozzle provided with equidistantly disposed ruptured gas venting means. It is also contemplated to have a protected blow-out disc interposed between the propellant and the preformed nozzle.

This application is a divisional application of our copending application Ser. No. 541,919, filed April 4, 1966, now Patent No. 3,345,902, which was a continuation-inpart application of Ser. No. 210,270, filed July 16, 196-2, the latter application being now abandoned.

This invention relates to an improved article of manufacture and its method of making. More particularly, the inventive concept relates to a miniature rocket as well as the new nozzle elements from which it is constructed.

The miniature ballistic rockets that have been revealed by the applicants are unusually etfective in ordnance applications. The size range which is appropriate for the indicated miniature rockets corresponds to the size range of conventional side arm rifle and possibly higher gauge shotgun calibers. In order to maintain the miniature size of these rockets, as well as allowing their use in conventional weapons with the attendant advantages, it is vitally important to provide a novel structure which will make the rockets more aerodynamically stable, thus eliminating the need for fins. As the launch tube diameter in most applications governs the dimension of a rocket, the removal of fins therefrom will allow a more productive utilization of this available diameter. Finless projectiles have many distinct advantages over conventional finned rockets, such as, better packing densities, easy to manufacture, easy to adapt to conventional weapons and more productively utilize the available volume than finned projectiles.

The use of a nozzle structure which converts linear momentum into angular momentum thereby bringing about rotation of the rocket in flight may be incorporated into miniature ballistic rockets while maintaining a structure which is easy to manufacture.

Simplicity of rocket design is of primary importance if the number of rockets produced is to be comparable with conventional bullets. Commensurate with this goal is the provision of a nozzle design which incorporates a primer cap or other ignition means in its structure while still maintaining its simplicity which will even further decrease the manufacturing expense and increase the usefulness of every round. Thus, it will be apparent that one of the most important factors in rocketry and particularly in the nozzle designs, is that they must be easily assemblable into the casing, particularly when the small size is considered.

Accordingly, nozzle designs may be also made which incorporate means for providing a restraining force on the rocket until the desired thrust magnitude is reached. This restraint prevents the premature launching of the rocket and erratic initial aerodynamic performance and nited States Patent thus allows a controlled set of launching conditions for every rocket.

One of the objects of the invention is to provide for the manufacture and assembly of a new type of rocket.

Another object of this invention is to provide a nozzle structure which may be utilized with conventional firearms.

Still another object of this invention is to provide a nozzle structure for a miniature ballistic rocket in which an ignition means is incorporated.

Yet another object of this invention is to provide a sealing means which is positioned over the primer chamber and the surrounding nozzles before the rocket is assembled.

Other objects and advantages will become apparent upon consideration of the following specification taken with the accompanying drawings which together form a complete disclosure of the invention, in which:

FIG. 1 shows a view in cross-section of the die members of one embodiment of the invention preparatory to upsetting a disc of metal to form the nozzle;

FIG. 2 is still another cross-sectional view of the die members after they have been brought into contacting relation with the disc and deformed it as shown:

FIG. 3 is a view generally similar to FIG. 2 which shows a pricking device for longitudinally aperturing the projecting chamber;

FIG. 4 is an end elevational view of the complete nozzle subsequent to its deformation;

FIG. 5 is a cross-sectional view of a propellant preparatory to being inserted in a cartridge casing;

FIG. 6 is a view partially in cross-section and partially in elevation showing the nozzle being introduced into the rocket casing;

FIG. 7 is a view of the completed rocket assembly shown partially in cross-section and partially in elevation; and

FIG. 8 is an end elevational view of the completed nozzle of another embodiment of the invention, the exhaust vents of which are created by a different type of die forming means.

Turning now to the drawings, and more particularly the view of FIG. 1, there is illustrated in cross-section a pair of die forming members comprising a male member 10 and a female member 12, the latter member being provided with any suitable means, such as shown at 14, to support the disc member 16, which is shown in elevation.

The axial center portion of the male member 10 is provided with a cylindrical portion 18 which terminates forwardly thereof in a chamfered portion 20 so that when the enlarged portion 18 is forced or punched into the disc under suitable pressure by means not shown, the disc is upset in the center area into the complementally formed recess 22 provided in the female die member.

Although there is provided, as shown in FIG. 1, an axially extending perforation 24 in the male member 10 which is adapted to accommodate a reciprocable pricking punch means 26 for penetrating the upset center of the disc after it has been upset, it is also contemplated that this pricking operation can be achieved simultaneously rather than sequentially.

With further reference to the drawings, and particularly FIG. 2, it is to be understood that the male die member 10 includes a plurality of substantially equidistantly disposed coextensive angularly arranged deforming means 28-28 (only two shown) which, when the upsetting operation takes place, distort the wall of the disc in predetermined areas, as indicated at 30-30, to Such an extent that they ultimately fracture tangentially thereof. This is best shown in FIG. 4.

FIG. 3 clearly shows the disc 16 under full or maximum pressure of the

die members

10 and 12 at about the time of the fracturing of the walls 3030 thereof. Substantially simultaneously with the application of maximum pressure to distort the disc to deform the metallic wall structure thereby forming the chamber 31, or immediately thereafter, the reciprocable pricking means 26 is advanced through the perforation 24 provided in the male member thence through the aperture 32 in the female member to thus form the completed nozzle 34.

Prior to describing the final steps in the assembly operation and at which time the rocket is formed, the die formation of a further embodiment of another and different type of nozzle will be discussed.

Reverting now to the male die 10, shown particularly in FIG. 1, attention is directed to the generally conical offstanding disc deforming members 2828, previously described.

In the manufacture of the second embodiment of the nozzle, which is shown in FIG. 8, the generally conical members 28-28 are eliminated and in lieu thereof the male die member is provided with struck-up pyramidlike portions which are capable of severing through the wall of the disc along three lines, all of which communicate at right angles to each other thereby providing a plurality of tangentially and angularly offstanding substantially equidistantly disposed coextensive tangs 36 which extend sufficiently above the surface of the wall of the disc 38 to thereby provide an exhaust gas outlet between the free cut area of the tang and the wall of the disc to cause the subsequently assembled rocket to revolve about its longitudinal axis in flight.

In FIGS. 5, 6 and 7, the final rocket assembly steps are shown. FIG. shows an exploded view of the rocket casing 50 open at one end preparatory to insertion of the perforated propellant 52 therein. The casing 50 includes depressions 54 therein thus creating spaced bosses 56' on the internal wall.

The view in FIG. 6 shows a relatively thin disc or wafer of aluminum 58 resting on the inwardly extending rim means 56 which is created by deforming the casing adjacent the opening, as shown. As an alternative, the wafer of aluminum, which should have a thickness not exceeding substantially two mils, may be secured over the offstanding nozzles and chamber and be pinched around the perimeter of the disc, whereupon the then completed nozzle assembly may be positioned on the rim 56 or boss means 56 of the casing and the end portion thereof flanged over as shown at 60, in FIG. 7, to provide the completed rocket.

The primer cap 62, shown only in an exploded view 4 in FIG. 7, may be assembled into the cavity 31 of the nozzle in any convenient stage of the operation, whether prior to assembly of the nozzle into the casing or as a final step after complete fabrication of the rocket.

That which is claimed is:

1. A miniature rocket comprising an elongated cylindrical casing including a Wall, a reduced nose portion and an open end portion adapted for insertion of a perforated propellant into said casing, a propellant in said casing, said casing wall being provided with means providing a reduced area adjacent its open end, a preformed disc-like nozzle insert having a perimeter lockably positioned in the open end of said casing and in edge contact with said means providing the reduced area, said nozzle insert including an axially extending primer chamber having a primer therein, said primer chamber also having a perforated nose portion terminating in the area of and adjacent to said propellant, a thin wafer of aluminum having a distended central portion and a peripheral area is supported on the means providing the reduced area on said casing and interposed between the nozzle insert and said perforated propellant, said preformed nozzle insert further including a plurality of substantially equidistantly disposed coextensive generally conical ruptured projections extending therefrom, each of said projections being ruptured at a common side, whereby the rocket will be caused to revolve about its longitudinal axis in flight.

2. A miniature rocket as claimed in claim 1, wherein the peripheral area of the wafer of aluminum is secured to the perimeter of the nozzle.

References Cited UNITED STATES PATENTS 2,412,173 12/1946 Pope.

2,605,607 8/1952 Hickman.

2,661,691 12/1953 Brandt.

2,701,525 2/1955 Hickman 10249.7 X

2,750,887 6/1956 Marcus 60201 2,762,193 9/ 1956 Johnson.

2,853,946 9/1958 Loedding 10249.3

2,938,430 5/1960 Pion l0249.7 X

2,990,684 7/1961 Cohen.

3,269,313 8/1966 Willmann et al 10249.7

VERLIN R. PENDEGRASS, Primary Examiner.

US. Cl. X.R.