US831947A - Priming device. - Google Patents

Priming device. Download PDF

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US831947A
US831947A US25584905A US1905255849A US831947A US 831947 A US831947 A US 831947A US 25584905 A US25584905 A US 25584905A US 1905255849 A US1905255849 A US 1905255849A US 831947 A US831947 A US 831947A
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primer
explosion
cap
charge
shell
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US25584905A
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Joseph W Graeme
Robert W Mcneely
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Joseph W Graeme
Robert W Mcneely
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F42AMMUNITION; BLASTING
    • F42CAMMUNITION FUZES; ARMING OR SAFETY MEANS THEREFOR
    • F42C19/00Details of fuzes
    • F42C19/08Primers; Detonators
    • F42C19/10Percussion caps

Description

No. 831,947. PATENTED SEPT, 25, 1906. J. W. GRAEME & R. W. MoNEELY. PRIMING DEVICE.
APPLICATION FILED APBJB. 1905.
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ATTORNEYS PATENTED SEPTL25, 1906.
J. W. GRABME 6a R. W. MoNBELY. PRIMING DEVICE.
APPLICATION FILED AYE. 15,1905.
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UNITED STATES PriTENT OFFICE.
JOSEPH WV. GRAEME AND ROBERT W. MONEELY, OF THE UNITED STATES NAVY.
PRIIVIING DEVICE.
Specification of Letters Patent.
Patented Sept. 25, 1906.
Application filed April 15,1905. Serial No. 255,849.
To all whom, it may concern.-
Be it known that we, JOSEPH. W. GRAEME and ROBERT W. MONEELY, of the United States Navy, citizens of the United States, residing at Washington, in the District of Columbia, now stationed at the United States Naval Gun Factory, have made certain new and useful Improvements in Priming Devices, of which the following is a specification.
This invention is an improvement in breech-loading ordnance, and has for an object to provide an improved primer, in connection with recording mechanism for indicating when the primer has been fired, to-
gether with means for increasing the efiiciency of the primer; and the invention consists in certain novel constructions and combinations of parts, as will be hereinafter de scribed and claimed.
In the drawings, Figure l is a vertical longitudinal section of a portion of the so-called mushroom and the primer. Fig. 2 is a detail section showingthe primer and the parts immediately associated therewith. Fig. 3 is a detail sectional view of the primer previous to firing. Fig. 4 is a detail sectional view of the primer after firing and after the plunger or anvil has been forced by the explosion rearwardly beyond the base of the primer to indicate the firing of its charge. Fig. 5 is a detail sectional view showing the invention embodied in a primer for use in cartridgecase guns. Fig. 6 is a detail enlarged section of a part of the construction shown in Fig. 5; and Figs. 7 and 8 are sectional views of a portion of the primer, showing a somewhat different construction from that presented in Figs.
3 and 4 and as will be hereinafter described. Fig. 9 shows a wire-gauze closure for the mouth of the primer. Fig. 10 is a detail sectional view of a portion of the primer with the indicating device and the cap in the position to which they are distorted by the force of the operation, the position of the cap previous to the explosion being indicated in dotted lines.
The primers at present in common use in the various military and naval establishments of the world often prove troublesome through their failure to fire when desired, owing to weakness of the explosive charge of the primer or to short circuits, jams, swelling of parts, or other causes within the primer.
When the gun does not fire after the electric or percussion or friction firing apparatus has been operated, it is not known whether or not the primer has exploded, as it is frequently impossible to hear the explosion of the primer due to the discharge of guns or other noises. It is the usual custom to wait about twenty minutes before opening the breech of the gun, although even after that interval of time the opening of the breech is attended with danger, as if the powder charge of a large turretgun should explode with the breech entirely or partly unlocked it would cause the destruction of the turret mechanism and crew, with the possible sinking of the ship through the explosion of the powder-magazine below the turret. Occasionally after a misfire of the primer the lock of the breech mechanism is opened and a fresh primer inserted; but this practice is open to great danger, for should the charge in the gun explode with no primer in the lock a serious accidentwould ensue, causing injury to the guns crew, the disabling of the lock, and probably the rendering temporarily useless of the gun.
Among the purposes of this invention are to render misfires of the primer and ignition of the charge in the gun, torpedo-tube, powder-chamber, or other receptacle less likely than at present and to avoid the delay of long waits and the dangers of premature openings of the breech mechanism or lock, as described above. This is effected by improvements in the primer, together with a certain and positive signal by which it may be readily determined whether or not the primer has exploded.
Manifestly the invention will not only be useful in ordnance and its allied arts, but will also be useful in any art where explosive primers or fuses are in use, as in mining, land or marine construction, pyrotechnics, agriculture, oil-well torpedoes, submarine and land mines, and other arts In the construction shown in Figs. 1 to 4 the metallic primer-case A is adapted in use to be inserted in the primer-chamber B, communicating with the re ar end of the vent or passage B through the stem of the socalled mushroom B, whose front end or head fits in practice within the rear end of the bore of the gun. The front end of the primer-chamber B preferably conver es or tapers at I) for engagement by the sdiding end cap E of the primer D. This tapering understood from Figs. 2 and 4 of the draw ings. By this means when the primer has exploded the electric circuit operates to signal such fact to the operator. The primer D may have a metal case D, as usual, and such case is provided at its open front end with an inwardly-turned flange D which engages in a groove E in the side of the sliding cap E when the latter is in its rearmost position, as shown in Fig. 3. The end cap is shouldered. at E in rear of the groove E and may preferably be made of a metallic substance, preferably Tobin bronze, or it may be made of compressed paper, fibrous material, wirenetting, or other suitable substance adapted to temporarily retain the pressure and heat of the exploded gases and materials of the primer and to thereby increase such pressure and heat by confining them in the primer-casing until the pressure has arisen sufficiently to burst out the outer end e of the cap E, as shown at e in Fig. 4, when an imperforate end e is employed, or to cause the exploded gases or materials of the primer to force their way out through the orifices in the cap if a perforated cap is employed, thus throwing the flames, &c., of the exploded primer charge into the propelling charge in the gun with a greater force, greater specd, and with more dispersion than would be the case if the cap were not used. It will therefore be seen that this cap forms in a measure a closure for the discharge end of the primer-- casing adapted to temporarily retain the exploded charge in order that the same may generate greater force and heat than ordinarily results. The velocity of the gases be- .ing increased, the time of passage of these gases through the vent of the mushroom to the propelling or other charge is considerably reduced. This time of passage is one of the divisions of the interval known in the art of ordnance as the firing interval and which firing interval is mainly composed of the time between the closing of an electric firingcircuit of the electric primer or the pulling of the trigger of the firing-lock of the percussion-primer and the issue of the projectile from the muzzle of the gun.
In Figs. 3 and 4 the shell of the primer is shown as crimped into connection with the sliding end cap. Where desired, a crimping of the primer into connection with the cap may be omitted, as shown in Figs. 7 and 9. In Fig. 7 the cap is shown as of paper-pulp,
tion shown in Figs. 2, 4, 6, and 8.
having a conical end, and this cap, it will be noticed, extends within the charge-chamber of the primer almost to the bottom thereof by touch or sight the particular character of the primer-that is to say, Whether it is electric, percussion, or of the combined form, as will be understood by those skilled in the art. As best shown in Figs. 2, 3, and 4, the plunger or anvil is formed to provide an efficient gas-check, having its stem made conical at 1 or tapered, so that when forced back it will bind within its guide-opening in the butt-end of the primer-shell and will prevent the exit of gas and will also operate to lock the plunger or anvil when forced re arwardly by the explosion of the charge in the primer-casing.
In operation the exploded charge will tend to force the sliding end cap of Figs. 1, 2, 3, and 4 forward to cause it to impinge against the tapered walls at b at the front end of the chamber B, thus closing the electric circuit F and indicating to the gun-crew that the primer had explodc d.
It is preferred to employ two different signaling or recording devices for indicating the firing of the primer, both being used for greater certainty and safety. One of these is the electrical signaling device operated by the sliding end cap of the primer-casing, as before described. The other consists in means operated by the recoil of the primer or a part thereof and preferably the central plunger or anvil G, having the spindle H extending to the rear end of the primer, as shown in Fig. 3, and operating upon the percussion-cap I. This anvil is held from accidental displacement by the safety-wire J and is arranged at its point end 9 to explode the cap I and then to be forced rearwardly by the explosion in the primer to tl lle posi- 0 revent the return of the anvil by the spring? K of the firing-pin K or the accidental or other return of the anvil, we provide for the interlocking thereof with the primer-casing when the anvil is forced rearwardly by the ex 10- sion in the primer. This may be effecte by providing within the shell or casing of the primer D an annular groove d, into which a thin lip or flange 9 on the anvil is forced by the explosion in the primer, thus causing the anvil to interlock with the primer-case when forced rearwardly to the position shown in Figs. 4 and 8 and to be retained in such position, as will be understood from said figures, or the plunger or anvil may be allowed to return to its original position before firing, which is accomplished by the omission of the annular groove (1. Manifestly the plunger or anvil may be that of an electric, percussion, friction, or combination electric and percussion primer and the recoil or counter-recoil of the primer being used in all cases to indicate the explosion of the primer by its action upon the hammer L or other suitable device on the lock, gun, or breech mechanism, this constituting in practice a visual signal, as shown in Figs. 2, 4, 6, and 8. In this connection it. will be understood that the fulmi- I nate cap will be distorted by the force of the explosion and forced outwardly, so that it will interlock with the primer-casing by entering the annular groove d, as shown in Fig. 10, and thus lock the plunger or anvil in its rearward position, this action of the cap supplementing in some instances the engagement of the lip or flange g in the groove g and in others taking the place of such lip or flange g, as will be understood from the drawings.
In the construction shown in Fig. 5 the plunger or anvil may be substantially like that shown in Figs. 3 and 4. However, in the construction in Figs. 7 and 8, which illustrates an electric primer, the plunger or anvil differs somewhat from that shown in Figs. 3 and 4. In this construction shown in Figs. 7 and 8 the annular groove M, forming a seat for the lip or flange M on the plunger or anvil, forms a part of the primer, although it is not a part of the outer shell thereof, as will be understood from the said figures.
In the operation of the invention it will be seen that when the primer is as shown in Fig. 8 its front end is rounded to facilitate its insertion into the chamber formed to receive it, and the plunger-anvil may be operated to explode the percussion-cap, and thus explode the charge within the primer. Such explosion of the primer charge will force the plunger or anv lrearwardly and will interlock the same with the primer-casing, so that the stem of the plunger-anvil will be held projected in such manner as to indicate the explosion of the charge in. the primer. The closure 6 at the point end of the primer will retain the gases, flames, &c., in the primer until their intensity forces the sliding cap forward, causing its end to conform to the tapered end wall of the primer-chamber and forms electrical contact with the terminal F and closes the electrical circuit, operating a signal, such as a light or other visual or audible signal, as may be preferred. We thus have a double signal indicating the explosion of the charge within the primer. We also provide for increasing the efliciency of the primer by retaining the primer explosion until its intensity is such as to insure its passage through the vent to the propelling charge of the gun or other device.
It will be noticed that the invention provides in connection with the primer a positively-operated signal for indicating the explosion of the primer charge.
It may be desirable in some instances to make the end cap or closure integral with the body portion of the shell or casing of the primer, and it will be understood that the end cap, whether integral or made separate from the body or shell of the primer, will form a substitute for the usual wad for retaining the contents of the primer.
The closure-cap when applied to fuses time, percussion, conibined time and percus sion, delayed action, or other fuses makes more certain the bursting of the explosive charge in the projectile, which charge tends to creep toward the point of the projectile during flight and after impact with any object, thus producing in base-fused shells a space between fuse and bursting charge across which the flame from the fuse must ass. p The invention will be found especially useful in increasing the efficiency of primers such as described, and the cap-closure may also be used in breech-loading rifles in which the propelling charge is contained in a bag or bags made of smokeless powder, colloids, or other inflammable material, or serge or other textile placed in the powder-chamber of the gun, or in the chamber uninclosed by a closed bag or case, or in rapid-fire guns in which the propelling charge is contained in a cartridge-case (metal preferred) placed in the chamber in the un or above water or submerged torpedo-tubes in which a gunpowder impulse is used for expelling the torpedo from the tube.
The metal cap inserted in or placed over the mouth of a primer or cartridge to increase the explosive power may be used in primers,
fuses for projectiles or other purposes, or
small-arm cartridges, in the Very stars for signaling at night, in pyrotechnics, in mining operations, in oil-we'll torpedoes, in marine and land construction work, in submarine mines, in agriculture for blowing up treestumps, &c., or for any other purpose for which explosive primers are of use. The metal cap may also be inserted in or placed over the mouth of blank cartridges to increase the sound of the report.
Having thus described our invention, what we claim as new, and desire to secure by Letters Patent, is-
1. The combination of a mushroom provided at its rear end with a primer-chamber and having a vent leading forwardly therefrom and having the front wall of the primerchamber tapered, an electric circuit in connection with the mushroom and having one of its terminals adjacent to the said tapered wall of the primer-chamber, the primer comprising a shell or casing, a sliding end cap forming a closure for the front of the primer and adapted to be forced by the explosion of the primer charge to conform to the tapered wall of the primer-chamber and to contact with the terminal adjacent to said wall, and the plunger-anvil having a lip or flange adapted to be spread by the explosion of the primer charge, the primer having a groove forming a seat for said flange when so spread, substantially as set forth.
2. A primer for use substantially as de scribed, comprising the primer case or shell, anda cap held to the casing or shell before and after explosion and forming a closure for the mouth of said shell, and forming a protection for the contents of the primer-case and adapted to be burst by the discharge of the primer substantially as set forth.
3. The combination substantially as de scribed, of the primer-chamber having a tapered wall forming a stop or abutment in advance of the inner end of the primer, the primer case or shell, and a cap forming a closure for the mouth of said primer-case and adapted to temporarily retain'the exploded charge whereby to cause a more complete combustion of such charge and to decrease the amount of partially-burned residue usually left in such devices and arranged when burst by the explosion of the primer to be forced to coincide with said tapered wall, substantially as set forth.
4. A primer provided at its mouth endwith a cap retained in connection with the primer-shell before and after explosion of the primer and forming a closure for retaining theexplosion of the primer charge and ad apted to burst or be ruptured for the passage of such charge when under an increased pressure, substantially as set forth.
5. A primer having its shell open at its mouth end and provided at such end with an inwardly-projecting lip or flange and a sliding end cap fitting in such open end of the primer-shell and engaged with the flange or lip thereof, substantially as described.
6. A primer-casing provided at its front end or mouth with a closure adapted to temporarily retain the exploded charge whereby the same may generate greater force and heat and to be ruptured by explosion of the primer, the said cap being retained in con nection with the casing before and after ex- I plosion, substantially as described.
7. A primer shell or case provided at its mouth or front end with a cap or closure adapted to be forced forward by the explosion of the primer charge, and a receiver for the primer having a stop for said cap.
8. A primer comprising the shell or case and the cap forming a closure for the mouth of the shell and sliding along such end of the shell.
9. A primer having a sliding end cap, forming a closure for the mouth end of the primer and movable relatively to the primer shell or primer-shell, whereby it may be actuated by t the explosion to operate upon an electrical circuit substantially as described.
12. A primer combined with a signal and means for positively operating such signal by the explosion of the primer charge and for retaining the signal in operated position ,where by to indicate the explosion of such charge, substantially as set forth.
13. A primer provided at its point end with a movable device adapted for operation by the explosion of the primer charge to close an electric circuit, and also having at its rear end a sliding plunger-anvil adapted to be forced rearwardly by the explosion of the primer charge, and also having means for positively detaining said plunger when retracted by the explosion of the primer charge, substantially as set forth.
14. The combination of an explosive primer and devices for indicating whether the said primer has been fired, and means for holding the indicating devices in indicating position when actuated thereto.
15. The combination of an explosive primer and means operated by the explosion of the primer charge for indicating whether the primer has been fired, and retained subsequent to the explosion of the primer.
1 6. A primer provided with a movable indicating device arranged for operation by the explosion and also provided with a portion adapted to be distorted by such explosion whereby to retain said device in indicating position, substantially as set forth.
17. In an apparatus substantially as described, the combination of an electric signaling-circuit and a primer having a movable part actuated by the explosion of the primer charge to operate the circuit, substantially as set forth.
18. A primer having a shell or casing and a part movable relative to the primer shell or casing whereby to operate a signal and retained in its position for operating the signal, substantially as set forth.
19. A primer comprising a shell, a recoiling indicating device at the butt-end of the shell, and adapted to be operated by the explosion of the primer charge, and a closure at the point end of the primer-shell, whereby to temporarily retain the exploded primer charge until the pressure thereof has risen be- IIO I yond the point it would reach if unconfined,
whereby to cause the recoiling indicating device at the butt-end of the primer to recoil with great force and rapidity and certainty, substantially as set forth.
20. A primer provided with means for temporarily retaining the pressure of its exploded charge, whereby to increase the said pressure and also provided with a movable indicating device arranged for operation by the explosion, and having a portion adapted to be distorted by such explosion, whereby to retain such device in indicating position, substantially as set forth.
21. A primer for use substantially as described, comprising a primer case or shell, and a cap slidable in connection therewith and adapted to be moved relatively to the shell by the explosion of the primer charge whereby to cause said cap to scrape or clean powder residue or other obstruction from an electric terminal upon which the said cap is forced by the pressure of the exploded primer charge, and an electrically-operated signal having its circuit arranged for operation by said cap, substantially as set forth.
22. A primer provided with a movable in dicating device arranged for operation by the explosion and also having a cap arranged to be distorted by the explosion to position to retain the indicating device in the position to which the latter is operated by the explosion.
.23. The combination of the tapered primer seat or abutment, and the primer having a shell or casing and a cap at the inner end of the primer and adapted to be forced by the pressure of explosion of the primer against the tapered seat or abutment, precluding the passage of gas along the outer side of the primer-shell, and subsequently ruptured by the force of such explosion, substantially as set forth.
24. The combination of the primer having a shell or casing and a cap at the inner end thereof, and a seat or abutment in advance of the primer and contracted relatively to the cap thereof whereby the said cap will be forced by the pressure of explosion within the primer to conform to and fit against the seat or abutment and then ruptured for the passage of the products of explosion, substantially as set forth.
25. The combination of the tapered primer seat or abutment, and the primer having a shell or casing, and a cap sliding along the inner end of the shell or casing and adapted to be forced by the pressure of explosion in the primer to conform to and fit against the tapered seat and to be subsequently ruptured for the passage of the products of explosion, substantially as set forth.
26. A primer for use substantially as described, comprising the primer case or shell, and a cap forming a closure for the mouth of said shell, which cap, on explosion of the charge contained in the said primer shell or cap, forces out and holds the mouth of the primer case or shell against the walls of the primerseat, preventing the escape of gas and residue between the primer case or shell, and the primer seat, therefore increasing the efficiency of the primer by keeping the primerseat perfectly clean and the primer a perfect gas-check.
27. The combination of the primer-chamber having a seat or abutment for the inner end cap of the primer, and a primer having at its inner end a cap spaced normally away from the seat or abutment and adapted to be forced by the initial pressure of the explosion of the primer against the said seat or abut ment and in conformity therewith, and subsequently ruptured for the passage of the products of explosion, substantially as and for the purpose set forth.
28. The combination of the primer having an internal recess, and the plunger-anvil movable rearwardly by the force of the explosion and having a lip or flange adapted to be spread by the explosion into said recess whereby to retain the said plunger-anvil in its rear position, substantially as set forth.
JOSEPH W. GRAEME. ROBERT W. MGNEELY.
Witnesses:
SoLo1\ C. KEMoN, PERRY B. TURPIN.
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Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3162122A (en) * 1961-10-24 1964-12-22 Ici Ltd Self-pressurizing detonators
US3169483A (en) * 1960-07-14 1965-02-16 Dynamit Nobel Ag Percussion cap
US4027592A (en) * 1975-02-06 1977-06-07 Dynamit Nobel Aktiengesellschaft Propellant charge igniter with striker element
US4195550A (en) * 1977-05-27 1980-04-01 Rheinmetall Gmbh Propellent charge igniter for caseless cartridges of separately loaded ammunition
US4457204A (en) * 1981-07-21 1984-07-03 Kitz Corporation Explosive charge-containing nut
US7117796B1 (en) * 2005-12-29 2006-10-10 The United States Of America As Represented By The Secretary Of The Navy Igniter for exothermic torch rod
US20190249970A1 (en) * 2018-02-15 2019-08-15 Goodrich Corporation High explosive firing mechanism

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3169483A (en) * 1960-07-14 1965-02-16 Dynamit Nobel Ag Percussion cap
US3162122A (en) * 1961-10-24 1964-12-22 Ici Ltd Self-pressurizing detonators
US4027592A (en) * 1975-02-06 1977-06-07 Dynamit Nobel Aktiengesellschaft Propellant charge igniter with striker element
US4195550A (en) * 1977-05-27 1980-04-01 Rheinmetall Gmbh Propellent charge igniter for caseless cartridges of separately loaded ammunition
US4457204A (en) * 1981-07-21 1984-07-03 Kitz Corporation Explosive charge-containing nut
US7117796B1 (en) * 2005-12-29 2006-10-10 The United States Of America As Represented By The Secretary Of The Navy Igniter for exothermic torch rod
US20190249970A1 (en) * 2018-02-15 2019-08-15 Goodrich Corporation High explosive firing mechanism
US10837747B2 (en) * 2018-02-15 2020-11-17 Goodrich Corporation High explosive firing mechanism

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