US3233545A

US3233545A - Practice projectiles

Info

Publication number: US3233545A
Application number: US261950A
Authority: US
Inventors: Heller Rudolf
Original assignee: Oerlikon Contraves AG
Current assignee: Rheinmetall Air Defence AG
Priority date: 1958-09-29
Filing date: 1963-02-27
Publication date: 1966-02-08
Anticipated expiration: 1983-02-08
Also published as: FR1244485A; NL242530A; CH374910A; BE582772A; DE1097320B; GB899496A

Description

Feb. 8, 1966 R. HELLER 3,233,545

PRACTICE PROJECTILES Filed Feb. 27, 1963 2 Sheets-Sheet 1 Feb. 8, 1966 R. HELLER 3,233,545

PRACTICE PROJECTILES Filed Feb. 27, 1963 2 Sheets-Sheet 2 &

\NVENTOR Kudo f/ //E f ATTORNEY United States Patent 3,233,545 PRACTItIE PROJECTRES Rudolf Heller, Zurich, Switzerland, assignor to Contraves A.G., Zurich, Switzerland Filed Feb. 27, 1963, Ser. No. 261,950 Claims priority, application Switzerland, Sept. 29, 1958,

7 Claims. b1. 102-311 this type can be directed in flight through connection over suitable means with a control station from where the soldier will give signals directing the projectile up or down or left or right, and with projectiles of this type considerable training and practice is necessary to enable the operator to properly control the projectile.

Such projectiles are quite expensive. When used for practice purposes they are identical with the real projectile except that they do not include the explosive charge which is carried by the real projectile. However, they do include such structures as the signal receiving equipment, the flight controlling fins, and the structure for translating the signals which are received into corresponding controls of these stabilizing fins so as to move the latter to give the projectile the desired direction of flight. Such projectiles normally travel at a speed of from 60 to 150 kilometers per hour, and when travelling at such speed these projectiles are seriously injured when they fall to the ground and more often than not it is not worthwhile to repair them. As a result practicing with these projectiles is extremely expensive.

One of the objects of the present invention is to provide a practice projectile of the above type which will not be injured when it falls to the ground so that it can be used again and again and thus the great cost involved in the use of such practice projectiles as outlined above is avoided.

Another object of the present invention is to provide a projectile of the above type with a structure which will reliably cause a parachute connected to the projectile to become operative when the projectile falls toward the ground so as to prevent injury to the projectile.

It is also an object of the present invention to provide a structure of the above type which is rugged and simple and very reliable in operation and which is at the same time quite flexible with respect to the different ways in which it can be controlled as to the discharge and actuation of the parachute.

With the above objects in view the present invention includes a projectile, a projectile body portion to the front end of which a hollow end portion of the projectile is removably connected, this hollow front end portion forming the front end of the projectile and in accordance with the present invention a parachute is housed within the hollow front end portion of the projectile, this parachute being connected to the body portion. The body portion of the projectile carries a means constructed in accordance with the present invention for removing the hollow front end portion of the projectile from the body portion of the latter while the projectile is in flight so as to release the parachute to the open air so that the parachute can expand and retard the falling of the projectile so as to prevent injury to the latter and thus enable the projectile to be used again.

The novel features which are considered as characteristic for the invention'are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings, in which:

FIG. 1 is a sectional elevational view of that part of a projectile which includes the structure of the invention; and

FIGS. 2a-2f illustrate various stages in the operation of a projectile which includes the structure of the invention.

Referring to FIG. 1 the projectile includes an elongated body portion 10 having a front end at which this body portion 10 is provided with a transverse wall 11. The transverse wall 11 is formed with a central opening and fixedly carries a cylinder 12 which may be formed integrally with the wall, the central opening of the wall 11 forming the front end of the cylinder 12, as illustrated in FIG. 1. The cylinder 12 is also open at its rear end where it is provided with outer threads. A piston 13 is slidable within the cylinder 12 through the opening in the front wall 11. It will be noted that piston 13 is provided at its rear end with an outwardly directed annular flange adapted to engage the shoulder in the interior of the cylinder 12 just behind the wall 11 so that forward movement of the piston 13 is limited in this way.

A closure member 14 is removably connected to the cylinder 12 by being threaded onto the rear end of the latter, and this closure member 14 closes the rear end of the cylinder 12. The closure member 14 carries at its inner face which is directed toward the interior of the cylinder 12 an explosive charge 15 in the form of any suitable cartridge carrying an explosive which will explode upon being ignited. A detonator cap 17 is carried by the closure member 14 and is actuated through the electrical lead 18 which ignites the detonator cap to cause the charge 15 to become ignited. Also, the closure 14 carries a simple fuse 16 which may be ignited by the operator before the projectile is put into flight so that eventually when enough time goes by the fuse 16 will have burnt suificiently to cause the charge 15 to be ignited in this way.

The body portion 10 of the projectile includes an annular ring 19 threaded onto the wall 11 in the manner shown in FIG. 1 and having a forwardly extending cylindrical wall portion 19. In addition, at its inner periph ery the annular member 19 is provided with a plurality of hooks 19" for a purpose pointed out below.

The projectile includes also a hollow front end portion or housing 21 shown in FIG. 1, this hollow front end portion or housing 21 shown in FIG. 1, this hollow front end portion 21 forming the front end of the projectile and being removably connected with the body portion 10 thereof. Thus, it will be seen from FIG. 1 that the hollow front end portion 21 slips at its rear end onto the cylindrical portion 19 of the ring 19, and the rear end portion of the member 21 as well as the front end por tion of the part 19' re provided with aligned openings. A plurality of shear pins 22 are located in these aligned openings, these shear pins being made of a relatively soft material so that the pins can be-sheared fairly easily when the front end portion 21 of the projectile is forcefully moved forwardly with respect to the body portion of the projectile.

A separating member 23 is located against a shoulder of the ring 19 at the inner surface of the wall 19 thereof, and this separating member 23 has a forwardly directed cylindrical portion engaging the rear end of the hollow front end portion 21. The separating member 23 is located forwardly of the transverse wall 11 and is formed with a plurality of openings 23 A parachute Z8 is located within the hollow front end portion 21 of the projectile forwardly of the separating member 23 and the cords 26 of the parachute respectively extend through the openings 23' and are respectively hooked onto the hooks 19" of the ring 19.

It is apparent that when during flight the charge 15 is ignited so as to drive the piston 13 forwardly, this piston will move the separating member 23 forwardly to push the hollow front end portion 21 forwardly with respect to the body portion 16 with a force sufi'icient to shear the pins 22 (preferably made of aluminum with a diameter of about /8 inch) so as to separate the hollow front end portion 21 from the body portion 10 and thus release the parachute which can open and retard the falling of the projectile so that the latter will not be injured and can be used again.

FIGS. 2a-2f illustrate the use of the projectile. As may be seen from FIG. 2a the operator A manipulates a suitable control device B which acts through the leads C on the projectile I), this projectile during flight remaining electrically connected with the control device B through the leads C in a well known manner. The operator A directs the projectile toward a suitable practice target and such a target is shown at B in FIG. 2.). Having manipulated the control device B so as to direct the projectile through the target B the operator now manipulates the control device B so as to direct the projectile upwardly and during this upward movement of the projectile the detonator 17 is set olf through a suitable control at the control device B so as to ignite the charge 15 and thus separate the hollow front end portion 21 forwardly along the axis of the projectile from the body portion 1t thereof as illustrated in FIG. 2d. FlG. 2c shows the instant when the front end portion 21 moves forwardly with respect to the body portion 1d, the pins 22. having been sheared, and FIG. 2d illustrates the front end portion 21 when it is located at a substantial distance beyond the body portion 19 with the cords 26 extending between body portion ill and front end portion 21 but the parachute 23 still is located in the latter. As may be seen from FIGS. and 2d, with the structure of the invention the housing 21, in which the parachute 28 is located, is thrown forwardly from the body portion 10 while the parachute 28 remains in the hollow housing 21, and in fact the parachute 28 remains in the housing 21 until all of the cords 26 become taut, as illustrated in FIG. 20?, and it is only thereafter that the front end portion or housing 21 becomes separated from the parachute. As a result of this construction it is not possible for the body portion M9 or the fins D to become driven into the parachute itself before it opens causing the parachute to become snarled on some other part of the projectile such as the body portion It or the fins D, and thus faultless opening of the parachute without any interference from any other part of the structure is guaranteed as a result of the forward movement of the housing 21 with the parachute 28 remaining therein until after the cords 26 become taut. PEG. 20 illustrates the projectile with the front end portion 21 completely separated from the parachute. The parachute 23 is acted upon by the stream of air so that it curves rearwardly in the manner shown in FIG. 2e and thus retards the forward movement of the projectile while at the same time the parachute fills with air and assumes the configuration shown in PEG. 2] so as to retard the falling of the projectile D and thus prevent injury to the latter. Thus all of the structure except element 21 forms a projectile unit which can be used repeatedly.

Instead of igniting the charge 15 at the will of the operator, it is possible to provide the device with a suitable timer which automatically ignites the charge 15 after passage of a predetermined period of time, or the fuse 16 may be ignited when the projectile is launched, this fuse 16 having such a length that a certain period of time is required for the fuse 16 to burn sufficiently to cause the charge 15 to become ignited. Thus, in this latter case the fuse 16 by its length talces over the function of the timer, and the fuse 16 may be ignited to guarantee ignition of the charge 15 in the event that the operator does not actuate the detonator 17 within a definite period of time.

Also, if desired, the practice field in which the projectile moves may be provided with auxiliary devices operated by radio waves, for example, which automatically set off the charge 15 when the projectile reaches a predetermined area of the practice field. The automatic signal transmitted in this way to the projectile while it is in flight so as to set off the charge 15 also can be set to actuate the projectile controls so as to automatically direct the projectile upwardly just before the charge 15 is ignited so that the projectile will have the proper attitude for the best operation of the parachute 28.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of projectiles differing from the types described above.

While the invention has been illustrated and described as embodied in practice projectiles, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without de= parting in any way from the spirit of the present in vention.

v'ltllOUt further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this inven= tion and, therefore, such adaptions should and are in tended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be secured by Letters Patent is:

1. In a practice projectile, in combination, a hollow front end portion forming the front of the projectile; an elongated projectile unit constituting all except the front of the projectile, means removably fixing said projectile unit to said hollow front end portion at the rear end of the latter, said projectile unit extending rearwardly from said front end portion, the interior of said hollow front end portion communicating with said projectile unit; a parachute located in said front end and having elongated cords connected with said projectile unit; and means between said front end portion and said projectile unit and cooperating with said hollow front end portion and driving the latter forwardly from the projectile unit while the projectile is in flight to place said cords in a taut condition before the hollow front end portion releases the parachute which then opens to retard the falling of the projectile unit to prevent injury to the latter so that it may be used again.

2. In a practice projectile, in combination, a hollow front end port-ion forming the front end of the projectile and an elongated projectile unit forming the remainder of the projectile and extending rearwardly from said hollow front end portion; means rem-ovably connecting said projectile unit to said hollow front end portion; a parachute located in said hollow front end portion and connected with said projectile unit through elongated cords of the parachute; an explosive charge carried by said projectile unit; means operatively connected to said charge for igniting the same while the projectile is in flight; and means interposed between said charge and said hollow front end portion for applying the force of the ignited charge to said hollow front end portion for driving the latter forwardly from said projectile unit to place the cords of the parachute in a taut condition and then to release the parachute from the hollow front end portion, the parachute then opening and retarding the falling of the projectile unit to prevent injury to the latter so that it may be used again.

3. In a practice projectile, in combination, an elongated projectile body portion having a front end and provided at said front end with a wall extending transversely across the projectile; .a piston carried by said wall for movement forwardly beyond the wall; an explosive charge removably carried by said wall behind said piston for moving the piston forwardly with respect to said wall when said charge is ignited; means operatively connected to said charge for igniting the same when the projectile is in flight; a hollow front end portion forming the front end of the projectile; means removably connecting said front end portion to said body portion of the projectile at the front end of said body portion, said hollow front end port-ion being located forwardly of and spaced from said wall; and a separating member located forwardly of said wall between the latter and said hollow front end portion and engaging said front hollow end portion, said separating member being located in the path of movement of said piston so that the piston will drive said separating member forwardly to separate said hollow front end portion from said body portion of said projectile, said separating member being formed with openings passing therethrough; and a parachute located in said hollow front end portion and having cords which extend through said openings of said Separating member to the space between the separating memher and said wall and said cords being connected to said body portion so that when the hollow front end portion is driven forwardly from said body portion While the projectile is in the flight the parachute cords will become taut and the parachute will then open to retard the falling of the projectile and prevent injury to the same so that the projectile can be used again.

4. In a practice projectile, in combination, a projectile body portion having a front end and provided at said front end with a transverse wall; a piston carried by said wall for movement forwardly with respect to the latter; an explosive charge removably carried by said wall behind said piston for moving the piston forwardly when said charge is ignited; means operatively connected to said charge for igniting the same when the projectile is in flight; a hollow front end portion forming the front end of the projectile and engaging and extending forwardly from said body portion; a plurality of shear pins connecting said hollow front end portion and said body portion so that when said pins are sheared the hollow front end portion will be separated from said body portion; a separating member located between said wall and hollow front end portion and engaging the front end portion, said separating member being located in the path of movement of said piston when the latter is moved upon ignition of said charge so that said separating member will drive said hollow front end portion forwardly with respect to said body portion to shear said pins and separate said hollow front end portion from said body portion, said separating member being formed with at least one open-ing; and a parachute located in said hollow front end portion forwardly of Said separating member and having cords extending through said opening to the rear of said separating member and connecting with said body portion so that said cords will become taut when the front end portion is driven forwardly and then the front end portion will release the parachute which then opens to retard falling of the projectile to prevent injury to the same so that the projectile can be used again.

5. In a practice projectile, in combination, a projectile body portion having a front end and provided at said front end with a transverse wall extending transversely across the body portion, said transverse wall being formed with a central opening and said transverse wall having connected therewith a cylinder extending rearwa-rdly from said transverse wall and axially aligned with said opening so that the opening forms the front end of said cylinder, said cylinder having an open rear end also; a piston slidable in said cylinder for movement forwardly beyond said wall; a closure member removably connected with said cylinder at the rear end of the cylinder for closing said rear end; an explosive charge carried by said closure member in the interior of said cylinder when said closure member closes said cylinder, so that when said charge is ignited said piston will be driven forwardly; ignition means carried by said closure member and operatively connected to said charge for igniting said charge while the projectile is in flight; a separating member carried by said body portion forwardly of said wall thereof in the path of movement of said piston to be moved forwardly by the latter upon ignition of said charge; a hollow front end portion forming the front end of said projectile and engaging and extending forwardly from said body portion; a plurality of shear pins removably connecting said hollow front end portion to said body portion, said separating member being formed with a plurality of openings pass-ing therethrough and said hollow front end portion of said projectile having a rear end which is engaged by said separating member; and a parachute located in said hollow front end portion forwardly of said separating member and having cords extending through said openings of the front end portion and connected with said body portion so that when the separating member is driven forwardly to shear said pins and thus separate said hollow front end portion from said body portion the parachute cords will become taut and the parachute will then be released to retard the falling of the projectile and thus prevent injury to the projectile so that the projectile can be used again.

6. In a practice projectile, in combination, a hollow front end portion forming the front of the projectile; an elongated projectile unit constituting all except the front of the projectile and fixed removably to said hollow front end portion at the rear end of the latter and extending rearwardly therefrom, the interior of said hollow front end portion communicating with said projectile unit; a parachute located in said front end portion; cords connecting said parachute only to said projectile unit;

and means in said projectile unit and adapted to act on said front end portion for driving the front end portion together with said parachute forwardly from the projectile unit with a speed greater than that of the unit to place said cords in taut condition whereupon the parachute is retarded to the speed of said projectile unit and becomes separated from said h-ollow front end portion so that the parachute is released from the front end portion and will open to retard falling of the projectile unit to prevent injury to the unit so that it may be used again.

7. In a practice projectile, in combination, a projectile unit having a front end portion and constituting almost the entire projectile; a hollow housing constituting the remainder of said projectile and having an open rear end; means removably connecting said rear end of the housing to said front end portion of said projectile unit so that said housing is coaxial-1y arranged with the projectile unit and projects forwardly therefrom; a separating member located in said front end portion of said projectile unit and engaging said rear end of said housing, said separating member being formed with openings passing therethrough; a folded parachute located in said hollow housing and having cords extending through said openings in said separating member and being connected to said projectile unit; means including an explosive charge carried in said front end portion of said projectile unit rearwardly of said separating member for exerting, when said charge is exploded, a blow in axial forward direction directly on said separating member so that the separating member will be driven forwardly to separate said housing from said front end portion of said projectile unit; and means operatively connected to said charge for exploding the same while said pro jectile is in flight, whereby when said charge is exploded said separating member and said hollow housing will be driven forwardly from said projectile unit so that said parachute cords will become taut and the parachute will then open to retard the falling of said projectile unit and prevent injury to the same so that the projectile unit can be used again.

References Cited by the Examiner UNITED STATES PATENTS BENFAMIN A. BORCHELT, Primary Examiner.

SAMUEL FEINBERG, Examiner.

R. F. STAHL, G. L. PETERSON, Assistant Examiners

Claims

1. IN A PRACTICE PROJECTILE, IN COMBINATION, A HOLLOW FRONT END PORTION FORMING THE FRONT OF THE PROJECTILE; AN ELONGATED PROJECTILE UNIT CONSTITUTING ALL EXCEPT THE FRONT OF THE PROJECTILE, MEANS REMOVABLY FIXING SAID PROJECTILE UNIT TO SAID HOLLOW FRONT END PORTION AT THE REAR END OF THE LATTER, SAID PROJECTILE UNIT EXTENDING REARWARDLY FROM SAID FRONT END PORTION, THE INTERIOR OF SAID HOLLOW FRONT END PORTION COMMUNICATING WITH SAID PROJECTILE UNIT; A PARACHUTE LOCATED IN SAID FRONT END AND HAVING ELONGATED CORDS CONNECTED WITH SAID PROJECTILE UNIT; AND MEANS BE-