US 1729550 A
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Description (OCR text may contain errors)
Sept. 24, 1929.
A. RUPP ORDNANCE MATERIAL Original Filed April 8, 1925 ,u E C Patented Sept. 24, 1929 PATENT OFFICE GUY RUPP, F ALLENTOWN, PENNSYLVANIA, ASSIGNOR TO TROJAN POWDER COMPANY, 0F NEW YORK, N. Y.,
A CORPORATION OF NEW YORK ORDNANCE MATERIAL Application filed April 8, 1925, Serial No. 21,529. Renewed February 23, 1929.
The principal object of this invention is to provide novel means for increasing the safety of handling ordnance material such as bombs, shells, sea mines and torpedoes, having thin envelopes liable to penetration by rifie and machine gun bullets and by shell fragments. More specifically the object is to reduce the liability of an explosive being detonated by a missile such as a bullet or shell fragment penetrating the metal enevolpe enclosing said explosive.
Several embodiments of the invention I have illustrated in the attached drawings, in which:
Fig. 1 is a longitudinal sectional view of a shell.
Fig. 2 is a longitudinal sectional view of a drop bomb, and
Fig. 3 is a view partly in section of a mine;
i all made in accordance with my invention.
I have discovered that by employing an insulating membrane of suitable material be tween the thin metal wall of the envelope and the contained explosive charge the resistance L of loaded shells, torpedoes, drop bombs and the like to explosion by a shell fragment or rifle bullet is materially increased.
In practice I have found that the material and physical form of the membrane may vary largely, although to be effect-ive it is ordina.- rily desirable that the layer of material between the metal container' and the explosive charge shall be not less than one-fourth of a millimeter in thickness, and preferably shall be in excess of one-half of a millimeter in thickness. In general, I have found it desirable that the membrane have the character-is tic of low-heat conducting capacity, and possess in some degree one or all of the chari acteristics of flexibility, resiliency, or compressibility; but there is to be implied no limitation as to the material or its physical characteristics.
` In one form of my invention I may employ i a thin layer of asbestos fibre or equivalent non-explosive material possessing the desired heat-insulating characteristics, together with a small amount of cushioning characteristic. Instead of asbestos fibre, however, I may use 1 fibres of wood pulp either alone or impregnated with rubber, magnesia or like material, and 1n a preferred form of my invention I may line a shell, or other metal envelope for a high explosive, with a mixture of asbestos fibre, magnesia and rubber latex, using approximately 6() parts of asbestos fibre, 10 parts of powdered magnesia, and parts of rubber latex. As this mixture dries, the water present in the rubber latex evaporates, leaving a compact and matted mass of asbestos fibres cemented togetherl by the rubber and with the particles of magnesia molded within the mass. This coating has admirable characteristics of resiliency and low heat conduction and represents a desirable embodiment of my invention. In another embodiment I may use a mixture of wood flour, cork dust and a drying oil so as to produce a layer or membrane of a composition similar to linoleum between the explosive charge and the outer metallic envelope or container.
Instead of employing an initially liquid or plastic coating for my shell, torpedo or the like, the protecting material may be in sheet form, and satisfactory results have been obtained by using asbestos paper and asbestos cloth, blotting paper, and ordinary cotton and vwoolen cloth.
Vith reference to Fig. l of the drawings, l designates the outer metallic envelope and 2 the liner, which preferably lies in contact with the inner face of the envelope. The bursting charge, not shown, occupies the interior of the envelope and is separated therefrom by the liner 2. In this form of shell, a booster charge is held in a suitable inner envelope 3 which projects inwardly and centrally from the nose 4 of the shell.
In Fig. 2, 1 designates the envelope of a drop bomb and 2 the protective liner. In this instance, a booster charge is held in an inner cylindrical envelope 3.
In Fig. 3 I have illustrated a contact mine comprising an outer casing 5 providing an air chamber and an inner envelope l for the bursting charge, the envelope l being provided with a protectivev lining 2. In this instance, also, an envelope 3 is provided for a booster charge.
' y In each-of the foregoing illustrations, vthe corresponding parts are given the same reference numerals. In each case, also, I have illustrated the preferred condition in Which the liner is in contact both With the envelope and With the explosive charge, although I do not Wish to lbe limited .to this particular arrangement. l
I have found that bombs and the like protected, as described, by membranes less than l mm. in .thickness have a resistance to explosion by rie bullets or shell fragments more thandouble the resistance of-V fered by a similar Weight of metal in the shell envelope, and the invention accordingly has a particularly valuable application to drop bombs as offering a method of materially increasing the safety of bombcarrying airplanes While using the thin Aenvelopes essential to a maximum Weight reduction. Y
While the invention finds an extremely practical applicatio'nfor the purpose vof increasing the safety of drop-bombs, torpedoes, shells, sea mines and the like, itis broadly applicable for protecting any thin- Walled metal container or envelope for high explosives that might be exposed to rifle bullets, shells or other missiles.
l. Ordnance material comprising a metal envelope of such thickness as to be readily penetrated by bullets, shell fragments or like missiles, an explosive'charge Within the envelope, and a protectivematerial interme- Y diate the charge and the metal Wall of the envelope for preventing detonation of the charge by a missile penetrating the envelope.
2, Ordnance material comprising a metal envelope of such' thickness as to beA readily penetrated by bullets, shell fragments or like missiles, an explosive charge Within the en-- velope, and a compressible protective materal between the charge and the metal Wall of the envelope capable of preventing detoynation of the charge When penetrated 'by said missile.
3. Ordnance material comprising a 1metal envelope of such thickness as to be readily penetrated by bullets, shell fragments and like missiles, an explosive charge Within the envelope, and a flexible `protective membrane between the charge and the metal Wall of the envelope for preventing vdeton'ation of the charge by a missile penetrating the envelope.
4. In combination, a metal envelope of such thickness as to be readily penetr'atedby bullets, shell fragments and like missiles, an explosive charge Within the envelope, and a protective membrane not less Vthan onefourth of a millimeter in thickness `between ythe charge and the envelope for preventing detonation of the charge by al'missile penetratinof the envelope. v
5. n combination, a metal/envelope fof ysuch thickness as to be readily penetrated by bullets, shell fragments and the like, an explosive charge Within the envelopes, and a protective material intermediate and in contact With the charge and With the metal Wall of the envelope for preventing detonation of the Acharge-by missiles penetrating the envelope. Y
6. In combination, a metal envelope of such thickness as to be readily penetrated by bullets, shell fragments .and like missiles, and a compressible protective material intermediate the charge and the metal Wall of the envelope and contacting With the latter for preventing detonation of the charge by missilespenetrating said envelope.
7. drop bomb compr'isinga metal envelope of such vthickness 'as to be readily penet-r'ated by b'ulfletsl,'shell fragments 'and like missiles, an explosive charge Within the envelope, and a protective material intermediate the charge 'and the metalWall 'of the envelope for preventing de'tonation of the charge by a missile penetrating the envelope.-
GUY A. RUPP.