US2447033A - Dummy projectile - Google Patents

Description

1943 M. SHAPIRO 2,447,033

DUMMY PROJECTILE Filed April 2'7, 1945 2 Sheets-Sheet 1 Aug. 17, 1948. M. SHAPIRO DUMMY PROJECTILE 2 Sheets-Sheet 2 Filed April 27, 1945 Patented Aug. 17, 1948 (Granted under the act of March 3, 1883, as amended April 30, 1928; 370 0. G. 757) 8 Claims.

The invention described herein may be manufactured and used by or for the Government for governmental purposes, without the payment to me of any royalty thereon.

This invention relates to a dummy projectile for use in loading practice drill, and it has for its object primaril the provision of such a projectile that can be readily extracted in a brief space of time and with minimum physical effort.

In loading projectiles of large caliber there is installed at the gun a power rammer and other mechanical contrivan-ces to expedite the handling and loading of such projectiles, and the dummy projectile employed in practice drill for such guns contains a freely moving plunger weighing several hundred pounds, whose inertia is employed in seating the rotating band against the forcing cone of the gun at the front of the powder chamber. This plunger is the source of trouble and it is eliminated from the projectile about to be described.

As intimated, these projectiles are rammed into the gun by a power rammer with such force that the rotating band is so firmly seated against the gun that very considerable force is required to extract the dunnny, so much in fact that breakage of the extractor staves frequently occurs. This breakage and other inconveniences and difficulties that occur incident to the method now employed are such as to cause delay in the routine of practice drill and to interfere materially with its usefulness.

In addition to the objects first stated, an object is to overcome the above mentioned difiiculties, and to this end I have devised a projectile that may, with the aid of a suitable wrench and extractor assembly, be extracted with little physical effort, such as that capable of being exerted by one man, and in no case more than two. The invention comprises a pseudo rotating band capable of being extended and locked to conform to the diameter of a live projectile band, but capable of being forcefully seated against the foreing cone in the ramming operation and being released from the cone so that the dummy can be removed from the gun with comparative ease. In the preferred embodiment of the invention the band comprises a plurality of arcuate sections capable of functionin in the manner and for the purpose mentioned.

In the drawings illustratin the invention,

Figure 1 is a section of a dummy projectile showing the improvement in elevation, on the ,rear end thereof;

Figure 2 is an enlarged central section of the rear end of the projectile;

Figure 3 is a rear elevation;

Figure 4 is a detail face view of one of the segments or sections of the rotating band;

Figure 5 is a vertical central section thereof;

Figure 6 is a fragmentary section showing the formation of the rear end of the projectile body, the section bein taken vertically through two of the rotating band recesses;

Figure '7 is a rear end view thereof;

Figure 8 is a sectional view of the rear end of the projectile showing the wrench and extractor assembly in the position it occupies in extending the rotating band prior to inserting the dummy into the gun and in retracting the band from contact with the forcing cone, and in extracting the dummy from the gun;

Figure 9 is an elevation of a spider for retainin the rotating band sections in place, and Fi ure 10 is a rear view thereof;

Figure 11 is an elevation of the operating lock, and Figure 12 is a rear view thereof showing the shape of the key hole therein for the insertion of the end of the wrench and extractor;

Figure 13 is an elevation of the outer ring nut, and Figure 14 is an edge View thereof;

Figure 15 is a rear view of the inner ring-nut, and Figure 16 is an edge view thereof;

Figure 17 is an elevation of a fragment of the wrench and extractor, and Figure 18 is an end view thereof.

Referring to the drawings, the numeral i designates the body of the projectile upon which is mounted the cap 2 to the rear of which is the rifling band 3, there being in the rear portion of the body a chamber or cavity 4. As shown in Figure 6, the rear open end of the body I is pro vided with four equally spaced longitudinal recesses 5. Adjacent these recesses the material of the body is reduced in diameter as at 6 to form annular shoulders I, and this reduced portion is further reduced as at 8, this last mentioned portion being provided externally and internally with screw threads for the reception of ring-nuts to be presently described.

Numeral 9 designates the rotatin band formed in the present embodiment of the invention of four identical arcuate segments or sections ill, each provided with a forcing cone engaging the portion l0, and a centrally located integral radial stem ll, whose lower ends are concave as at l2 for accurate engagement with an operatin element of the organization.

The segments are received in the recesses 5 and silde radially therein in their inward and outward movements. The stems l I are each provided with a through-aperture l2 inclined rearwardly and downwardly for the reception of legs 13 of a circular spider Hi, the legs [3 serving to hold the rotating band segments in place. The spider is centrally apertured for the passage of a headed bolt l5 whose threaded shank is threaded centrally into the rear wall of an operating look It, the connection between the spider and operating lock being such that the lock can rotate independently of the spider in being moved to extend or retract the rotating band segments. The lock I6 is in the form of a truncated cone whose periphery accurately fits the concave ends of the rotating band stems. vide-d at the rear of the cone portion with an annular flange I? which in one position is in abutting relation with the lower rear edges of the segment stems, as clearly shown in Figure 2. The lock [6 has a-central cavity I8 communicated with from the rear of the projectile through a key hole IQ for the entrance of the end of the wrench and extractor assembly, as will more fully appear. The cavity in the lock is spanned by two oppositely disposed pins for engagement with the wrench end.

Integral with the lock is a boss 2| externally threaded for cooperation with the threads of an internally and externally threaded inner ringnut 22, this ring-nut being rabbetted as at 23 to allow for the necessary axial movement of the operating lock, and it is also threaded into the reduced portion 8 of the projectile body. Threaded onto this reduced portion 8 of the projectile body is another and outer ring-nut 24, rabbetted as at 25 to accommodate the short rearwardly extending portions of the rotating band. It is necessary that these ring-nuts have no considerable movement when the operating lock is being moved, and consequently they are locked together by two screws such as indicated at 26. The rotating band segments as stated, slide radially in their respective recesses and appropriate clearances are allowed for their slight movement. The fit between the segments and their stems and the parts against which they abut is such as to be snug but free from any binding tendencies in their movement from extended position in which they engage with the forcing cone, to the other or retracted position in which they are released from the cone preparatory to the extraction operation.

The numeral 21 designates the wrench extractor asembly as a whole. This may be constituted by a rod of suitable diameter and appropriate length, but I prefer to make the shaft of the wrench in tubular form to the end of which is rigidly attached the rod 28 provided with a blade 29 extending at right angles to the rod, which blade is adapted to be inserted into the key hole in the operating lock [6 for engagement with the pins in the cavity of the lock, the other end of the tube being provided with a handle 30 of length to provide the proper leverage in the operation of rotating the lock and in extracting the dummy.

Operation: The end of the wrench is inserted in the key hole into the operating lock and turned until the Wings of the blade engage the pins 28 when further movement in the appropriate direction, will rotate the lock, and if the lock is rotated to move it inwardly, the cone surface will force the sections of the rotating band outwardly to adapt the projectile for ramming into the gun. Obviously rotation of the lock in the opposite direction will release the band sections and permit The operating lock is prothem to move simultaneously inward, facilitating the comparatively easy removal of the projectile from the gun, which is then effected by a pull upon the wrench.

I claim:

1. A projectile for use in loading practice drill, comprising a body provided at its rear end with a plurality of equally spaced longitudinal recesses, a rotating band formed of a plurality of arcuate sections each provided with a stem seated in one of said recesses, an outer ring-nut threaded on the rear end of the body and providing rearward support for said rotating band, an inner ring threaded into the rear end of said body, an operating lock threaded into said inner-ring-nut and rotatable with relation to said nut, said lock having an inner end in the form of a truncated cone whose periphery is in operative engagement with the ends of the stems of the rotating band sections whereby when the lock is rotated in one direction the said sections will be moved positively outward simultaneously, and when rotated in the opposite direction, said sections will be released and. permitted to move simultaneously inward, and non-rotatable means carried by said lock to engage said arcuate sections to prevent independent movement of the respective sections.

2. The invention of claim 1 characterized in that the operating lock is provided with an internal cavity housing means carried by said lock for engagement with extraneous means for rotating said lock, and an aperture in the lock for the introduction of said means.

3. A projectile for use in loading practice drill,

, comprising an elongated steel body having a plurality of equally spaced longitudinal recesses formed. therein at its rear end, a plurality of identical arcuate segments each provided with a radial stem adapted to be seated in a respective one of the said recesses, the said arcuate segments combining to form a rotating band for the said projectile, securing means adapted to engage said radial stems to hold said segments in place and to prevent radial movement of any one or more of the said segments independently of the other segments, a conical locking member positioned in the base of said body with its periphery operatively engaging the ends of said stems, the said locking member being adapted for rotary movement independent of segment securing means mounted thereon and having a central cavity therein and an aperture communicating with the cavity from the rear of the member, the said member being provided with means within the said cavity engageable by a wrench insertable through the said aperture for effecting rotation of the member, an inner ring nut threaded into the said body and on said locking member to permit axial translation of said locking member relative to said body when the said locking member is rotated by said wrench whereby when the said member is rotated in one direction the said arcuate segments will be moved positively outward simultaneously, and when mtated in the opposite direction said segments will be released and permitted to move simultaneously inward, and an outer ring nut threaded on the said body to hold the entire assembly and to provide an abutment which cooperates with the inner ring to prevent rearward movement of the segments independently of the projectile.

4. The structure of claim 3 in which the securing means to prevent independent radial moveiment of the respective segments comprises a spider non-rotatably mounted on the conical locking member and slidably engaging the re-- spective radial stems of the said segments in apertures provided therein for such purpose.

5. The structure of claim 3 in which the means provided in said central cavity comprises oppositely disposed pin members spanning said cavity for engagement therein with the end of said Wrench.

6. The structure of claim 3 in which the lower ends of the stems of the respective arcuate segments are concave for accurate engagement with the said conical locking member.

7. The structure of claim 3 in which screw means is provided to lock together the inner and outer rings whereby the said rings cooperate to limit rotary movement of said rings relative to said conical locking member while said member is being moved.

8. A projectile for use in loading practice drill, comprising a body having a rotating band formed of a plurality of arcuate sections mounted for radial movement in said body, said arcuate sections having portions extending inwardly of said body provided with inclined slots; a member rotatably mounted in the rear end of said body, a spider having inclined legs cooperating with said inclined slots and supported by said member, said member and said spider cooperating, and constructed and arranged to simultaneously extend said sections when rotated in one direction, and to withdraw said sections when rotated in the opposite direction, said member having a cavity therein and an aperture communicating with the cavity from the rear of said member, said member being provided within the cavity with means engageable for efiecting the rotation of said member.

MICHAEL SHAPIRO.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 34,493 Havens Feb. 25, 1862 112,121 Butler Feb. 28, 1871 FOREIGN PATENTS Number Country Date 706,280 Germany May 22, 1941

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