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US1690331A - Supersensitive fuse for drop bombs - Google Patents

Supersensitive fuse for drop bombs Download PDF

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Publication number
US1690331A
US1690331A US731469A US73146924A US1690331A US 1690331 A US1690331 A US 1690331A US 731469 A US731469 A US 731469A US 73146924 A US73146924 A US 73146924A US 1690331 A US1690331 A US 1690331A
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United States
Prior art keywords
carrier
fuse
cap
primer
detonator
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Expired - Lifetime
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US731469A
Inventor
Harold M Brayton
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SECRETARY OF WAR OF UNITED
SECRETARY OF WAR OF United States,
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SECRETARY OF WAR OF UNITED
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Priority to US731469A priority Critical patent/US1690331A/en
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Expired - Lifetime legal-status Critical Current

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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F42AMMUNITION; BLASTING
    • F42CAMMUNITION FUZES; ARMING OR SAFETY MEANS THEREFOR
    • F42C15/00Arming-means in fuzes; Safety means for preventing premature detonation of fuzes or charges
    • F42C15/18Arming-means in fuzes; Safety means for preventing premature detonation of fuzes or charges wherein a carrier for an element of the pyrotechnic or explosive train is moved
    • F42C15/184Arming-means in fuzes; Safety means for preventing premature detonation of fuzes or charges wherein a carrier for an element of the pyrotechnic or explosive train is moved using a slidable carrier
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F42AMMUNITION; BLASTING
    • F42CAMMUNITION FUZES; ARMING OR SAFETY MEANS THEREFOR
    • F42C15/00Arming-means in fuzes; Safety means for preventing premature detonation of fuzes or charges
    • F42C15/28Arming-means in fuzes; Safety means for preventing premature detonation of fuzes or charges operated by flow of fluent material, e.g. shot, fluids
    • F42C15/295Arming-means in fuzes; Safety means for preventing premature detonation of fuzes or charges operated by flow of fluent material, e.g. shot, fluids operated by a turbine or a propeller; Mounting means therefor

Definitions

  • the subject of this invention is a supersensitive fuse for drop bombs.
  • the bomb In dropping bombs from one airplane on to another, the bomb must strike some vital or substantial part of the plane to afford sufficient resistance to detonate the ordinary impact fuse. As the greatest area of the plane consists in the wings and fuselage which are covered with fabric, a fuse of this description on striking the fabric, will not function and the bomb will pass through the plane without being exploded.
  • the fuse forming the subject of the present invention is provided with a supersensitive air balanceable striker head which will produce an instant-aneous detonation when arrested in flight by the fabric covering of the plane.
  • the explosive train is normally held in unarmed position and incapable of being moved to armed position until the air propeller has completed a predetermined number of revolutions.
  • the rotation of the propeller moves the primer element of the explosive train longitudinally of the fuse and in position to be struck by the firing pin on impact at which time the detonating element is free to be moved laterally of the fuse to be positioned in line with the primer and booster.
  • the air propeller assembly unlike most adaptations does not unscrew its stem or shaft from the fuse during flight, but is rotatably secured to the fuse casing and functions by moving a member in threaded engagement therewith which carries the primer and the release rod for the detonator.
  • Fig. 1 is a longitudinal section of my improved fuse
  • Fig. 2 is a sectional .view taken on the line 2-2 of Fig. 1;
  • Fig. 3 is asectional view taken on the line of Fig. 1; and f Fig. 4 is a sectional view 44 of Fig. 1.
  • the fuse casmg comprises a body 10, formed with a reduced forward portion to marginallyseat a cap 11. which constitutes the nose of the fuse.
  • the cap s formed with annular flange 12, whereby it is rotatably held to the body by the overhanging rim of a collar 13, which is threaded to. the body 10.
  • I ltlgldly secured to the exterior of the cap 11 1s a propeller 14, which is set in motion to rotate the cap by the rush of air when the bomb 1s released.
  • the propeller is normally held against rotation by a safety pin (not shown) which passes through'an ear 15 of the propeller and a similar car 16 formed on a r ng 17 whlch encircles the ,collar 13 and is rigidly fastened to the collar and the body by means of pins 18 and 19.
  • the safety pin may be attached to the release mechanism of the plane so that it will be withdrawn when the bomb is dropped.
  • the cap 11 is internally threaded to receive the head of a cylindrical carrier 20, which is T-shaped 1n longitudinal section, the stem21 thereof being normally disposed axially within the fuse body 10.
  • the carrier is constrained to be translated forwardly to armed po-sitlon during rotation of the cap 11, by means of a guide and passing through the carrier, and incidentally, by means of a release rod 23 movablewith the carrier and functioning to normally hold a detonating element out of'line with a booster.
  • the carrier 20 is centrally bored through out its length to provide a flash duct 24 for a P1111161 25 situated at the mouth thereof in the forward face of the carrier.
  • the head of the cap is exteriorly formed with an annular extension 26 to which is threaded a member 27 having an inturned taken on the line
  • the striker head is in the form of an inverted cup, its exterior face formed with a depression 30, which merges with a stem 31 carrying a fixed firing pin 32, the point end rim 28 for retaining a movable striker head pin 22 carried by the body 7 of which normally projects within the cap 11.
  • Ports 33 are provided in the face of the striker to permit influx of air into the striker head, while the wall of the striker is provided with apertures 34 which are positioned in advance of the rim 28 when the striker is extruded to functioning position.
  • the firing pin is retracted to and maintained -in armed position by the static pressure developed in the striker, so that it will not interfere with the primer when the carrier is moved to the head of the cap 11.
  • a detonator carrier comprising a cylindrical bolt 35 mounted transversely in the body to be moved laterally under the action of a spring 36 until it comes to rest against a plug'37.
  • the bolt is formed with a vertical opening in which is frictionally retained a cup 38 carrying a detonator 39, which will be positioned axially of the fuse when the bolt is in armed position.
  • Thebolt is guided and prevented from rotating during its lateral movement by apin 40, which at the proper moment, is forced by means of a spring 41 into a recess in the bolt to securely lock the bolt in armed osition so that the detonator will be held in a ignment with a booster charge 42 carried in the base of the body 11 and spaced from the main charge by a disc 43.
  • a fuse seat liner 44 in the form of a thimble is normally assembled to the bomb for shipping and is tapped to receive the base end of the body 11.
  • the carrier when in armed position. has withdrawn the release rod 23 a suflicient distance to permit the bolt to move laterally of the fuse and position the detonator in line with the booster and the flash duct.
  • the sensitive striker Upon impact, the sensitive striker will drive the firing pin rearwardly to prime the primer, which in turn will set off a rapid det onation so that the propellent charge will be exploded before the bomb has passed entirely through the plane.
  • the construction'of the primer carrier may be altered to permit a squared stem formed thereon to engage in a recess in the bolt or detonator carrier 35, the stem of the primer carrier thus serving to perform the function of both the guide pin 22 and the release rod 23.
  • a nose fuse for bombs including a body, a cap rotatably secured thereto, a propeller for rotating'the cap, a carrier constrained to be translated to the head of the cap through rotation of said cap, a primer disposed in the carrier, an air balanceable striker head including a firing pin mounted on the cap, a
  • cylindrical bolt mounted transversely in the bod a detonator in said bolt, means secured to t e carrier for releasably holding the bolt in unarmed position, and means for guiding the bolt in lateral movement and for looking it in armed position.
  • a nose fuse for bombs including a body
  • a cap rotatably secured thereto, a propeller. 'for rotating the cap, a carrier movable to armed position through rotation of the cap, a primer disposed in the carrier, an air balanceable striker head mounted on the cap, a cylindrical bolt mounted transversely in the body, a detonator in said bolt, means secured to the carrier for releasably holding the bolt in unarmed position, and means for guiding the bolt in lateral movement and for looking .it in armed position.
  • a nose fuse for bombs including a body, a cap rotatably secured thereto, a propeller for rotating the cap, a carrier movable to armed position through rotation of the cap, a primer disposed in the carrier, an air balanceable striker head mounted on the cap, a bolt mounted transversely in the body, a detonator in said bolt, and means secured to the carrier for releasably holding the bolt in unarmed position.
  • a nose fuse for bombs including a body, a cap rotatably secured thereto, a propeller for rotating the ca a primer carrier movable to armed position t ough rotation of the cap,
  • an air balanceable striker head mounted on said bolt, and means opera le on rotation of the propeller, to release the bolt to armedposition.
  • a nose fuse for bombs including, a body,
  • a primer carrier mounted axially of the body
  • a detonator carrier mounted transversely of the body, means operable during flight for moving the primer carrier to armed position, and means associated with said carrier for releasing the detonator carrier to armed position.
  • a nose fuse for bombs including a body, a primer carrier mounted axially of the body, a detonator carrier mounted transversely of the body, and means operable during flight for successively moving the carriers to armed position.
  • a nose fuse'for bombs including a body, a primer carrier mounted in the body, a detonator carrier mounted in the body at an angle to the primer carrier, means operable during flight for moving the primer carrier to armed position, and sald primer carrier controlling the movement of the detonator carrier to armed position.
  • a nose fuse for bombs including a body, a primer carrier mounted in the body, a detonator carrier mounted in the body,- means operable during flight for moving the primer carrier to armed position, and said primer carrier controlling the movement of the detonator carrier to armed position.
  • a nose fuse for bombs including a body, a primer carrier mounted in the body, a detonator carrier mounted in the body, and means operable after release of and during flight of the bomb for enabling the carriers to be moved to armed position.
  • a nose fuse for bombs includin a cap, means for rotating said cap during 'ght, a primer carrier movable through rotation of said cap to armed position, an air balanceable striker head mounted on the cap, and a fixed firing pin carried thereby and adapted on functioning of the striker to be moved away from the primer.
  • a nose fuse for bombs embodying a cap, an air balanceable striker head including a firing pin adapted on release of the bomb to be immediately moved to armed position, a propeller for rotating the cap, and a primer carrier whose moment of arming is controllable by the rotationof the propeller.
  • a fuse for bombs including a body, a
  • cap rotatably secured thereto, means for rotating the cap during flight, a detonator carrier movably mounted transversely of the body, a primer carrier in threaded engagement with the cap, and a rod for releaseably holding the detonator carrier in unarmed position and constraining the primer carrier to be translated on rotation of said cap.
  • a fuse including a firing pin normally in firing position and movable to armed position during flight, a detonator carrier, and a primer carrier normally in unarmed position and holding the detonator carrier in unarmed position, said primer carrier movable to armed position before releasing the detonator carrier.

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Air Bags (AREA)

Description

Nov. 6, 1928. 1,690,331
' H. M. BRAYTON NSITIVE FUSE FOR DROP BOMBS Filed 11, 19,24
Patented Nov. 6, 1928 UNITED STATES 1,690,331 PATENT OFFHIE.
HAROLD M. BRAYTON, OF DOVER, NEW JERSEY, ASSIGNOR TO SECRETARY OF WAR OF THE UNITED STATES OF AMERICA.
SUPERSENSITIVE FUSE FOR DROP BOMBS.
Application filed August 11, 1924. Serial No. 731,469.
(GRANTED UNDER THE ACT or MARCH 3, 1883, AS Anemia!) nan. a0, 1928; s70 o. e. 757.)
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.
The subject of this invention is a supersensitive fuse for drop bombs.
In dropping bombs from one airplane on to another, the bomb must strike some vital or substantial part of the plane to afford sufficient resistance to detonate the ordinary impact fuse. As the greatest area of the plane consists in the wings and fuselage which are covered with fabric, a fuse of this description on striking the fabric, will not function and the bomb will pass through the plane without being exploded.
To overcome this objection, the fuse forming the subject of the present invention, is provided with a supersensitive air balanceable striker head which will produce an instant-aneous detonation when arrested in flight by the fabric covering of the plane.
According to the invention, the explosive train is normally held in unarmed position and incapable of being moved to armed position until the air propeller has completed a predetermined number of revolutions. The rotation of the propeller moves the primer element of the explosive train longitudinally of the fuse and in position to be struck by the firing pin on impact at which time the detonating element is free to be moved laterally of the fuse to be positioned in line with the primer and booster.
The air propeller assembly unlike most adaptations does not unscrew its stem or shaft from the fuse during flight, but is rotatably secured to the fuse casing and functions by moving a member in threaded engagement therewith which carries the primer and the release rod for the detonator.
To these and other ends, my invention consists in the construction, arrangement and combination of elements, described hereinafter and pointed out in the claims forming a part of this specification.
A practical embodiment of my invention is illustrated in the accompanying'drawings, in which,
Fig. 1 is a longitudinal section of my improved fuse Fig. 2 is a sectional .view taken on the line 2-2 of Fig. 1;
Fig. 3 is asectional view taken on the line of Fig. 1; and f Fig. 4 is a sectional view 44 of Fig. 1.
Referring to the drawings by numerals of reference: According to thein'vention the fuse casmg comprises a body 10, formed with a reduced forward portion to marginallyseat a cap 11. which constitutes the nose of the fuse. The cap s formed with annular flange 12, whereby it is rotatably held to the body by the overhanging rim of a collar 13, which is threaded to. the body 10. I ltlgldly secured to the exterior of the cap 11 1s a propeller 14, which is set in motion to rotate the cap by the rush of air when the bomb 1s released. The propeller is normally held against rotation by a safety pin (not shown) which passes through'an ear 15 of the propeller and a similar car 16 formed on a r ng 17 whlch encircles the ,collar 13 and is rigidly fastened to the collar and the body by means of pins 18 and 19. The safety pin may be attached to the release mechanism of the plane so that it will be withdrawn when the bomb is dropped.
The cap 11 is internally threaded to receive the head of a cylindrical carrier 20, which is T-shaped 1n longitudinal section, the stem21 thereof being normally disposed axially within the fuse body 10. The carrier is constrained to be translated forwardly to armed po-sitlon during rotation of the cap 11, by means of a guide and passing through the carrier, and incidentally, by means of a release rod 23 movablewith the carrier and functioning to normally hold a detonating element out of'line with a booster.
The carrier 20 is centrally bored through out its length to provide a flash duct 24 for a P1111161 25 situated at the mouth thereof in the forward face of the carrier.
The head of the cap is exteriorly formed with an annular extension 26 to which is threaded a member 27 having an inturned taken on the line The striker head is in the form of an inverted cup, its exterior face formed with a depression 30, which merges with a stem 31 carrying a fixed firing pin 32, the point end rim 28 for retaining a movable striker head pin 22 carried by the body 7 of which normally projects within the cap 11. Ports 33 are provided in the face of the striker to permit influx of air into the striker head, while the wall of the striker is provided with apertures 34 which are positioned in advance of the rim 28 when the striker is extruded to functioning position.
The firing pin is retracted to and maintained -in armed position by the static pressure developed in the striker, so that it will not interfere with the primer when the carrier is moved to the head of the cap 11.
When the primer carrier has been moved to armed position, it withdraws the release rod 23 a suflicient distance to enable a detonator carrier comprising a cylindrical bolt 35 mounted transversely in the body to be moved laterally under the action of a spring 36 until it comes to rest against a plug'37. The bolt is formed with a vertical opening in which is frictionally retained a cup 38 carrying a detonator 39, which will be positioned axially of the fuse when the bolt is in armed position.
Thebolt is guided and prevented from rotating during its lateral movement by apin 40, which at the proper moment, is forced by means of a spring 41 into a recess in the bolt to securely lock the bolt in armed osition so that the detonator will be held in a ignment with a booster charge 42 carried in the base of the body 11 and spaced from the main charge by a disc 43.
A fuse seat liner 44 in the form of a thimble is normally assembled to the bomb for shipping and is tapped to receive the base end of the body 11.
In operation, assuming the bomb to have been released the rotation of the propeller and cap 11 moves the primer carrier to armed position at the head of the cap where it is eld until impact. During this movement of the carrier, the air balanceable striker head is extruded to functioning position and withdraws the point end of the firing -pin so that it will not interfere with the primer when the carrier is in armed position.
The carrier when in armed position. has withdrawn the release rod 23 a suflicient distance to permit the bolt to move laterally of the fuse and position the detonator in line with the booster and the flash duct.
Upon impact, the sensitive striker will drive the firing pin rearwardly to prime the primer, which in turn will set off a rapid det onation so that the propellent charge will be exploded before the bomb has passed entirely through the plane.
If desired, the construction'of the primer carrier may be altered to permit a squared stem formed thereon to engage in a recess in the bolt or detonator carrier 35, the stem of the primer carrier thus serving to perform the function of both the guide pin 22 and the release rod 23.
While in the foregoing there has been illustrated and described such combination and arrangement of elements as constitute the preferred embodiment of my invention, it is nevertheless desired to em hasize the fact that interpretation of the 1 .vention should only be conclusive when made in the light of the subj oined claims.
I claim:
1. A nose fuse for bombs including a body, a cap rotatably secured thereto, a propeller for rotating'the cap, a carrier constrained to be translated to the head of the cap through rotation of said cap, a primer disposed in the carrier, an air balanceable striker head including a firing pin mounted on the cap, a
cylindrical bolt mounted transversely in the bod a detonator in said bolt, means secured to t e carrier for releasably holding the bolt in unarmed position, and means for guiding the bolt in lateral movement and for looking it in armed position. 7
2. A nose fuse for bombs including a body,
a cap rotatably secured thereto, a propeller. 'for rotating the cap, a carrier movable to armed position through rotation of the cap, a primer disposed in the carrier, an air balanceable striker head mounted on the cap, a cylindrical bolt mounted transversely in the body, a detonator in said bolt, means secured to the carrier for releasably holding the bolt in unarmed position, and means for guiding the bolt in lateral movement and for looking .it in armed position.
3. A nose fuse for bombs including a body, a cap rotatably secured thereto, a propeller for rotating the cap, a carrier movable to armed position through rotation of the cap, a primer disposed in the carrier, an air balanceable striker head mounted on the cap, a bolt mounted transversely in the body, a detonator in said bolt, and means secured to the carrier for releasably holding the bolt in unarmed position.
4. A nose fuse for bombs including a body, a cap rotatably secured thereto, a propeller for rotating the ca a primer carrier movable to armed position t ough rotation of the cap,
an air balanceable striker head mounted on said bolt, and means opera le on rotation of the propeller, to release the bolt to armedposition.
6. A nose fuse for bombs including, a body,
a primer carrier mounted axially of the body,
a detonator carrier mounted transversely of the body, means operable during flight for moving the primer carrier to armed position, and means associated with said carrier for releasing the detonator carrier to armed position.
7. A nose fuse for bombs including a body, a primer carrier mounted axially of the body, a detonator carrier mounted transversely of the body, and means operable during flight for successively moving the carriers to armed position.
8. A nose fuse'for bombs including a body, a primer carrier mounted in the body, a detonator carrier mounted in the body at an angle to the primer carrier, means operable during flight for moving the primer carrier to armed position, and sald primer carrier controlling the movement of the detonator carrier to armed position.
9. A nose fuse for bombs including a body, a primer carrier mounted in the body, a detonator carrier mounted in the body,- means operable during flight for moving the primer carrier to armed position, and said primer carrier controlling the movement of the detonator carrier to armed position.
10. A nose fuse for bombs including a body, a primer carrier mounted in the body, a detonator carrier mounted in the body, and means operable after release of and during flight of the bomb for enabling the carriers to be moved to armed position.
11. A nose fuse for bombs includin a cap, means for rotating said cap during 'ght, a primer carrier movable through rotation of said cap to armed position, an air balanceable striker head mounted on the cap, and a fixed firing pin carried thereby and adapted on functioning of the striker to be moved away from the primer.
12. A nose fuse for bombs embodying a cap, an air balanceable striker head including a firing pin adapted on release of the bomb to be immediately moved to armed position, a propeller for rotating the cap, and a primer carrier whose moment of arming is controllable by the rotationof the propeller.
13. A fuse for bombs including a body, a
cap rotatably secured thereto, means for rotating the cap during flight, a detonator carrier movably mounted transversely of the body, a primer carrier in threaded engagement with the cap, and a rod for releaseably holding the detonator carrier in unarmed position and constraining the primer carrier to be translated on rotation of said cap.
14. A fuse including a firing pin normally in firing position and movable to armed position during flight, a detonator carrier, and a primer carrier normally in unarmed position and holding the detonator carrier in unarmed position, said primer carrier movable to armed position before releasing the detonator carrier.
HAROLD M. BRAYTON.
US731469A 1924-08-11 1924-08-11 Supersensitive fuse for drop bombs Expired - Lifetime US1690331A (en)

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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2480563A (en) * 1943-09-04 1949-08-30 Us Navy Safety device for fuses
US2594340A (en) * 1940-09-19 1952-04-29 George M O'rear Centrifugally armed fuse
US2625881A (en) * 1949-08-03 1953-01-20 Rabinow Jacob Double element setback lock
US2805623A (en) * 1951-09-07 1957-09-10 Raymond H Blair Tail fuze for an ordnance missile
US4726292A (en) * 1985-06-28 1988-02-23 Fratelli Borletti S.P.A. Fuse for sub-munitions to be expelled from a rocket

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2594340A (en) * 1940-09-19 1952-04-29 George M O'rear Centrifugally armed fuse
US2480563A (en) * 1943-09-04 1949-08-30 Us Navy Safety device for fuses
US2625881A (en) * 1949-08-03 1953-01-20 Rabinow Jacob Double element setback lock
US2805623A (en) * 1951-09-07 1957-09-10 Raymond H Blair Tail fuze for an ordnance missile
US4726292A (en) * 1985-06-28 1988-02-23 Fratelli Borletti S.P.A. Fuse for sub-munitions to be expelled from a rocket

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