US3075465A - Centrifugal fuze - Google Patents

Centrifugal fuze Download PDF

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Publication number
US3075465A
US3075465A US675794A US67579457A US3075465A US 3075465 A US3075465 A US 3075465A US 675794 A US675794 A US 675794A US 67579457 A US67579457 A US 67579457A US 3075465 A US3075465 A US 3075465A
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Prior art keywords
missile
projectile
rotor
fuze
base
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US675794A
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Donald E Craig
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Philips North America LLC
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Magnavox Co
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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
    • F42C15/28Arming-means in fuzes; Safety means for preventing premature detonation of fuzes or charges operated by flow of fluent material, e.g. shot, fluids
    • F42C15/285Arming-means in fuzes; Safety means for preventing premature detonation of fuzes or charges operated by flow of fluent material, e.g. shot, fluids stored within the fuze housing

Definitions

  • This invention relates generally to a fuze device and more particularly to a fuze adapted to arm a missile or projectile after a predetermined delay period following the time of launching of the missile or projectile.
  • the principal object of this invention is to provide a fuze for missiles or projectiles which is responsive to forces created by the rotational movement of the missile or projectile after it is launched for arming a detonator.
  • Another object of this invention is to provide a fuze for a missile or projectile which is adapted to operate an electrical circuit or an arming mechanism of any other suitable type after the lapse of a predetermined time period from time of launching the missile or projectile.
  • Still another object of this invention is to provide a fuze for a missile or projectile which has an arming mechanism operable after a certain time period has elapsed after the time of launching the missile or projectile and which includes a mechanism for creating such delay which is substantially unaffected by temperature, humidity, mechanical shock or the like.
  • a fuze for a missile or projectile comprising an arming mechanism, means responsive to forces created by rotation by said missile or projectile after it is launched for actuating said arming mechanism, a trigger device adapted to release said force responsive means when said missile or projectile is launched, and means cooperating with said trigger device and said force responsive means for timing the movement of said force responsive means and providing a delay period between the initiation of its movement and its actuation of said arming mechanism.
  • FIG. 1 is -a top plan view of the fuze provided in accordance with this invention.
  • FIG. 2 is a cross-section taken on line 2 2 of FIG. l;
  • FIG. 3 is a front elevation of the device illustrated in FIG. l;
  • FIG. 4 is a rear elevation of FIG. l;
  • FIG. 5 is a side elevation taken from the right-hand side of FIG. 1;
  • FIG. 6 is a detailed perspective view of the conductor supporting insulator utilized in the fuze illustrated in FIG. l;
  • FIG. 7 is a detailed front elevation of the structure shown in FIG. 6 together with top and bottom insulators cooperating therewith.
  • rl'he fuze as provided in accordance with this invention comprises a base member 111 adapted to be mounted in a missile or projectile rwith its longitudinal axis corresponding generally with the longitudinal axis of the missile or projectile.
  • the arming mechanism of the fuze may be electrical or mechanical, but for purposes of illustrating this invention a portion of an electrical arming mechanism consisting of a iilamentary or foil-like conductor 11 is shown in electrical contact with the rod-like electrical terminals 12 and 114.
  • Conductor 11 may be supported on a central insulating member 1S and extend over its upper surface, over a retainer linger 15a, and downwardly across the end thereof to form a severable portion at 16. The remainder of conductor 11 may be laid along the lower surface of insulator 15 over retainer lingers 15b and 15e and joined to the end of the terminal 14.
  • terminals 12 and 14 are mounted within suitable bores in the base 10 as illustrated in FIG. 5.
  • the inner end of terminal 12 projects through central insulator 15 to its upper side, as at 12a while the inner end of terminal 14 extends only to the lower side of insulator 15, as at 14a.
  • rl ⁇ he outer ends of terminals 12 and 14 project outwardly of base 10 to provide terminal portions which may be connected electrically with a detonator in the conventional fashion.
  • Terminals 12 and 14 are illustrated from base 1li by cylindrical insulators 17.
  • top and bottom insulators 18 and 19 are placed above and below the central insulator 1S.
  • a cover 20 which may be fastened to the base lll by means of suitable machine screws 21.
  • the arming mechanism is actuated by a rotor 23, rotatably mounted in the base 1li by means of a pin 24 one end of which is nested within a bore 25 in base 10, the other end of which extends into bore 26 of a rotor cover 2li.
  • Cover 2S may be secured to the base 10 by a plurality of machine screws 29 threaded into bores 30 in the base 10 and engaging shoulder portions 31 formed in cover 28 by cutting out the cover as at 32.
  • Rotor 23 has a notch 34 extending approximately 90 around its periphery whereby the end portion 15a' of insulator 15 may extend inwardly beyond the outer periphery of the rotor 23.
  • a knife 37 of insulating material is mounted with its cutting edge facing into the cut-out portion.
  • the knife 37 may be fastened to rotor 23 in any suitable manner, but for purposes of illustration it is shown as having a shank 38 within which is mounted a pin member 39, the outer ends of which cooperate with bores in the rotor to hold the knife in place.
  • Notch 34 unbalances rotor 23 so that rotation of the missile or projectile will cause rotor 23 to rotate relative to base 10 and move knife 37 toward the severable portion 16 of conductor 11.
  • Insulator 15 is grooved at 15e so that knife 37 may enter this groove to cut conductor 11 at 16 and effect arming of the missile or projectile. In this manner, the arming mechanism and the rotor structure act as an electrical switch.
  • a trigger mechanism in the form of slide 41, one end of which is held within a notch 42 formed on the periphery of rotor 23 by means of a leaf spring 43 positioned within a recess 44 formed in the base 1t) adjacent the outer end of slide 41.
  • a cover 4S fastened by means of screws 46.
  • rI ⁇ he yslide 41 is normally locked with its inner edge engaging notch y42 of rotor 23 by means of a set-back pin 48.
  • Pin 48 is arranged with its longitudinal axis in parallel with the longitudinal axis of the fuze and missile so that accelerative forces at the time of launching of the missile or projectile will dislodge pin 48 from engagement with slide y41, thereby unlocking slide 41 so that it can respond to rotative forces created by rotation by the missile or projectile and move out of notch 42 against the force created by spring 43.
  • Pin 48 is prevented from moving in response to normal shock forces by means of a coil spring y49 (FIG. 4) supported within a slot 50 on a shaft 51 mounted within the base 1G.
  • Spring 49 has an end portion 52 bearing on the outer end of pin 4S. The other end 53 of spring 49 is locked within a slot 54 in base 10. Normal shock forces are insuiicient to flex portion 52 of spring 49 but acceleration forces on pin 48 create sufficient force on portion 52 to iiex the spring 49 thereby to permit pin 4 to move out of engagement with slide 41.
  • a number of glass beads 56 disposed within a cut-out portion 57 on the periphery of rotor 23 and confined within this space by rotor cover 28 and the wall portions of base 10 which surround the rotor.
  • the slide 41 moves outwardly in' response to rotative forces of the missile or projectile far enough to create a gap between the Wallv58 of rotor 23 and the end of slide 41 which engages within notch 42.
  • the beads may then escape at a, certain rate' through the restricted passage between the end of slide 41 and wall 58 thereby causing rotor 23 to rotate at a predetermined speed.
  • This predetermined speed of rotation provides a delay period after the missile isired and'before knife 37 can cut the conductor 11.
  • the set-back pin 48y ilexes spring 49 and moves out of engagement with the slide or trigger 41 in response. to an acceleration force created when the missile or projectile is launched.
  • This movement of slide 41 opens a slot between the walls of notch 42 and the wall 58 of'cut-out portion 57 on the periphery of ⁇ rotor 23.
  • Rotation of a missile or projectile also causes counter-rotationof rotor 23' in-a-counter-clockwise direction, for example.
  • this invention provides a mechanism having a relatively simple structure with a small number of parts for providing a delay period before the detonator of the missile or projectile is armed after launching.
  • the mechanism is substantially unaffected by temperature, humidity, shock or other' conditions, whereby it is safe during shipment or other handling and untilV after it has f been launched.
  • said disk including a notch, a trigger device releasable by launching forces and comprisingr a slide mounted in said base for movementV relative to said base out of said notch to form ⁇ a slot and a. set-back pin disposed longitudinally of said base and engaging said slide,l
  • said disk including a ⁇ cut-out portion on its peripheryy forming a continuation of said notch and filled with small beads whereby rotationk of said disk is controlled by ow of said beads through the sloty between saidy slide and the walls of said notch.

Description

Jan. 29, 1963 D. E. CRAIG 3,075,465
CENTRIFUGAL F'UZE Filed July 23, 1957 2 Sheets-Sheet 1 INVETOR. Do/mw E. CRn/6.
/7 TRNff-S.
Jan. 29, 1963 D. E. CRAIG 3,075,465
CENTRIFUGAL FUZE Filed July 23, 1957 2 Sheets-Sheet 2 United States arent tice 3,975,465 CEN'I'RFUGAL FUZE Donald E. Craig, Fort Wayne, Ind., assigner to rEhe llt/Iagnavox Company, Fort Wayne, Ind., a corporation Filed .lilly 23, 1957, Ser. No. 675,794 1 Claim. (Cl. H12-76.2)
This invention relates generally to a fuze device and more particularly to a fuze adapted to arm a missile or projectile after a predetermined delay period following the time of launching of the missile or projectile.
The principal object of this invention is to provide a fuze for missiles or projectiles which is responsive to forces created by the rotational movement of the missile or projectile after it is launched for arming a detonator.
Another object of this invention is to provide a fuze for a missile or projectile which is adapted to operate an electrical circuit or an arming mechanism of any other suitable type after the lapse of a predetermined time period from time of launching the missile or projectile.
Still another object of this invention is to provide a fuze for a missile or projectile which has an arming mechanism operable after a certain time period has elapsed after the time of launching the missile or projectile and which includes a mechanism for creating such delay which is substantially unaffected by temperature, humidity, mechanical shock or the like.
In accordance with this invention there is provided a fuze for a missile or projectile comprising an arming mechanism, means responsive to forces created by rotation by said missile or projectile after it is launched for actuating said arming mechanism, a trigger device adapted to release said force responsive means when said missile or projectile is launched, and means cooperating with said trigger device and said force responsive means for timing the movement of said force responsive means and providing a delay period between the initiation of its movement and its actuation of said arming mechanism.
The full nature of the invention will be understood from the accompanying drawings and the following description and claim:
FIG. 1 is -a top plan view of the fuze provided in accordance with this invention;
FIG. 2 is a cross-section taken on line 2 2 of FIG. l;
FIG. 3 is a front elevation of the device illustrated in FIG. l;
FIG. 4 is a rear elevation of FIG. l;
FIG. 5 is a side elevation taken from the right-hand side of FIG. 1;
FIG. 6 is a detailed perspective view of the conductor supporting insulator utilized in the fuze illustrated in FIG. l; and
FIG. 7 is a detailed front elevation of the structure shown in FIG. 6 together with top and bottom insulators cooperating therewith.
rl'he fuze as provided in accordance with this invention comprises a base member 111 adapted to be mounted in a missile or projectile rwith its longitudinal axis corresponding generally with the longitudinal axis of the missile or projectile. The arming mechanism of the fuze may be electrical or mechanical, but for purposes of illustrating this invention a portion of an electrical arming mechanism consisting of a iilamentary or foil-like conductor 11 is shown in electrical contact with the rod-like electrical terminals 12 and 114. Conductor 11 may be supported on a central insulating member 1S and extend over its upper surface, over a retainer linger 15a, and downwardly across the end thereof to form a severable portion at 16. The remainder of conductor 11 may be laid along the lower surface of insulator 15 over retainer lingers 15b and 15e and joined to the end of the terminal 14.
The terminals 12 and 14 are mounted within suitable bores in the base 10 as illustrated in FIG. 5. The inner end of terminal 12 projects through central insulator 15 to its upper side, as at 12a while the inner end of terminal 14 extends only to the lower side of insulator 15, as at 14a. rl`he outer ends of terminals 12 and 14 project outwardly of base 10 to provide terminal portions which may be connected electrically with a detonator in the conventional fashion. Terminals 12 and 14 are illustrated from base 1li by cylindrical insulators 17. In order to insulate conductor 11 from the base 1li, top and bottom insulators 18 and 19 are placed above and below the central insulator 1S. For holding the members 12, 14, 15, 18 and 19 in position, there is provided a cover 20 which may be fastened to the base lll by means of suitable machine screws 21.
The arming mechanism is actuated by a rotor 23, rotatably mounted in the base 1li by means of a pin 24 one end of which is nested within a bore 25 in base 10, the other end of which extends into bore 26 of a rotor cover 2li. Cover 2S may be secured to the base 10 by a plurality of machine screws 29 threaded into bores 30 in the base 10 and engaging shoulder portions 31 formed in cover 28 by cutting out the cover as at 32. Rotor 23 has a notch 34 extending approximately 90 around its periphery whereby the end portion 15a' of insulator 15 may extend inwardly beyond the outer periphery of the rotor 23.
At one end of notch 34, a knife 37 of insulating material is mounted with its cutting edge facing into the cut-out portion. The knife 37 may be fastened to rotor 23 in any suitable manner, but for purposes of illustration it is shown as having a shank 38 within which is mounted a pin member 39, the outer ends of which cooperate with bores in the rotor to hold the knife in place. Notch 34 unbalances rotor 23 so that rotation of the missile or projectile will cause rotor 23 to rotate relative to base 10 and move knife 37 toward the severable portion 16 of conductor 11. Insulator 15 is grooved at 15e so that knife 37 may enter this groove to cut conductor 11 at 16 and effect arming of the missile or projectile. In this manner, the arming mechanism and the rotor structure act as an electrical switch.
For normally holding the rotor 23 in a safe position, there is provided a trigger mechanism in the form of slide 41, one end of which is held within a notch 42 formed on the periphery of rotor 23 by means of a leaf spring 43 positioned within a recess 44 formed in the base 1t) adjacent the outer end of slide 41. For holding slide 41 and spring 43 in operative position, there is provided a cover 4S fastened by means of screws 46.
rI`he yslide 41 is normally locked with its inner edge engaging notch y42 of rotor 23 by means of a set-back pin 48. Pin 48 is arranged with its longitudinal axis in parallel with the longitudinal axis of the fuze and missile so that accelerative forces at the time of launching of the missile or projectile will dislodge pin 48 from engagement with slide y41, thereby unlocking slide 41 so that it can respond to rotative forces created by rotation by the missile or projectile and move out of notch 42 against the force created by spring 43.
Pin 48 is prevented from moving in response to normal shock forces by means of a coil spring y49 (FIG. 4) supported within a slot 50 on a shaft 51 mounted within the base 1G. Spring 49 has an end portion 52 bearing on the outer end of pin 4S. The other end 53 of spring 49 is locked within a slot 54 in base 10. Normal shock forces are insuiicient to flex portion 52 of spring 49 but acceleration forces on pin 48 create sufficient force on portion 52 to iiex the spring 49 thereby to permit pin 4 to move out of engagement with slide 41.
For controlling the speed of rotation of rotor 23, there are provided a number of glass beads 56 disposed within a cut-out portion 57 on the periphery of rotor 23 and confined within this space by rotor cover 28 and the wall portions of base 10 which surround the rotor. The slide 41 moves outwardly in' response to rotative forces of the missile or projectile far enough to create a gap between the Wallv58 of rotor 23 and the end of slide 41 which engages within notch 42. The beads may then escape at a, certain rate' through the restricted passage between the end of slide 41 and wall 58 thereby causing rotor 23 to rotate at a predetermined speed. This predetermined speed of rotation provides a delay period after the missile isired and'before knife 37 can cut the conductor 11. In operation, the set-back pin 48y ilexes spring 49 and moves out of engagement with the slide or trigger 41 in response. to an acceleration force created when the missile or projectile is launched. The rotative forces which occur immediately after the missile or projectile is launched, caused the slide 41 to move outwardly toward the periphery of the base 10' against the retarding force of spring 43. This movement of slide 41 opens a slot between the walls of notch 42 and the wall 58 of'cut-out portion 57 on the periphery of`rotor 23. Rotation of a missile or projectile also causes counter-rotationof rotor 23' in-a-counter-clockwise direction, for example.
'Therefore the beads 56 are forced through the slot between the endof slide 41 and the walls 42 and 58. The width ofthe slot and the forcesA tending to rotate rotork 23 determine the rate of ow of the beads through the slot. This rate of flow in turn determines the amount of time required for rotor 23 to rotate from the-position shown'in FIG. 1 to aposition wherefknife37 engages the loop'16 offconductor 11".- After this predetermined time' interval, knife 37r will cut conductor 11, thereby to arm the detonatingmechanism of the missile or projectile after the missile or projectile has travelled along its trajectory'for a certain distance.
From the foregoing description, it will be apparent that this invention provides a mechanism having a relatively simple structure with a small number of parts for providing a delay period before the detonator of the missile or projectile is armed after launching. The mechanism is substantially unaffected by temperature, humidity, shock or other' conditions, whereby it is safe during shipment or other handling and untilV after it has f been launched.
missile or projectile whereby it is responsive to forces, Y
created by rotation of said missile or projectile after it is launched, said disk including a notch, a trigger device releasable by launching forces and comprisingr a slide mounted in said base for movementV relative to said base out of said notch to form` a slot and a. set-back pin disposed longitudinally of said base and engaging said slide,l
said disk including a` cut-out portion on its peripheryy forming a continuation of said notch and filled with small beads whereby rotationk of said disk is controlled by ow of said beads through the sloty between saidy slide and the walls of said notch.
References Cited in the tile of this patent- UNITED STATES PATENTS 896,135 Meigs et al Aug. 18, 1908 2,485,817 Dike Oct. 25, 1949 2,737,890 Erode Mar. 13, 1956 2,750,889 Kuhn June 19, 1956 2,825,284 Kuhn Mar. 4, 1958Vv 2,971,463 Burrell Feb. 14,1961.
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Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3119303A (en) * 1960-09-23 1964-01-28 Hotchkiss Brandt Gyratory self-propelled projectile
US3450047A (en) * 1967-11-08 1969-06-17 Us Army Spin stabilized projectile with self-destructive capability
US3721195A (en) * 1971-06-01 1973-03-20 Honeywell Inc Liquid revolution counter for fuze arming
US3776140A (en) * 1971-11-22 1973-12-04 Us Army Shot vortex arming device
US3962973A (en) * 1974-10-29 1976-06-15 Motorola, Inc. Time delay control mechanism
US3985079A (en) * 1975-10-20 1976-10-12 The United States Of America As Represented By The Secretary Of The Army Self-destruct fuze for spinning artillery projectile
US4012613A (en) * 1960-12-23 1977-03-15 The United States Of America As Represented By The Secretary Of The Navy Inertial switch
US4320705A (en) * 1979-03-19 1982-03-23 Societe Anonyme Sormel Safety device for a pyrotechnic assembly
US5056434A (en) * 1990-08-27 1991-10-15 Magnavox Government And Industrial Electronics Company Spin integrating safe and arm device for spinning munitions

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US896135A (en) * 1904-12-19 1908-08-18 Bethlehem Steel Corp Mechanical time-fuse.
US2485817A (en) * 1943-04-16 1949-10-25 Us Navy Detonator safety device
US2737890A (en) * 1942-11-09 1956-03-13 Robert B Brode Safety unit for explosive devices
US2750889A (en) * 1950-05-20 1956-06-19 Mefina Sa Fuses for projectiles
US2825284A (en) * 1954-11-05 1958-03-04 Mefina Sa Impact fuzes with mechanical retardation
US2971463A (en) * 1951-07-30 1961-02-14 Burrell Ellis Spherical pellet delay device

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US896135A (en) * 1904-12-19 1908-08-18 Bethlehem Steel Corp Mechanical time-fuse.
US2737890A (en) * 1942-11-09 1956-03-13 Robert B Brode Safety unit for explosive devices
US2485817A (en) * 1943-04-16 1949-10-25 Us Navy Detonator safety device
US2750889A (en) * 1950-05-20 1956-06-19 Mefina Sa Fuses for projectiles
US2971463A (en) * 1951-07-30 1961-02-14 Burrell Ellis Spherical pellet delay device
US2825284A (en) * 1954-11-05 1958-03-04 Mefina Sa Impact fuzes with mechanical retardation

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3119303A (en) * 1960-09-23 1964-01-28 Hotchkiss Brandt Gyratory self-propelled projectile
US4012613A (en) * 1960-12-23 1977-03-15 The United States Of America As Represented By The Secretary Of The Navy Inertial switch
US3450047A (en) * 1967-11-08 1969-06-17 Us Army Spin stabilized projectile with self-destructive capability
US3721195A (en) * 1971-06-01 1973-03-20 Honeywell Inc Liquid revolution counter for fuze arming
US3776140A (en) * 1971-11-22 1973-12-04 Us Army Shot vortex arming device
US3962973A (en) * 1974-10-29 1976-06-15 Motorola, Inc. Time delay control mechanism
US3985079A (en) * 1975-10-20 1976-10-12 The United States Of America As Represented By The Secretary Of The Army Self-destruct fuze for spinning artillery projectile
US4320705A (en) * 1979-03-19 1982-03-23 Societe Anonyme Sormel Safety device for a pyrotechnic assembly
US5056434A (en) * 1990-08-27 1991-10-15 Magnavox Government And Industrial Electronics Company Spin integrating safe and arm device for spinning munitions

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