US3139828A

US3139828A - Inertia responsive fuze

Info

Publication number: US3139828A
Application number: US263528A
Authority: US
Inventors: Delaney John; Hallsworth Victor
Original assignee: Ferranti PLC
Current assignee: Ferranti International PLC
Priority date: 1962-03-08
Filing date: 1963-03-07
Publication date: 1964-07-07
Anticipated expiration: 1981-07-07
Also published as: BE629210A; CH423552A; DE1187158B; GB967188A

Description

July 7, 1964 1. DELANEY ETAL.

INERTIA RESPONSIVE FUzE 6 Sheets-She??l l Filed March 7, 1963 u, Q/j N@ J Inventors JOHN DELANEY VLCTOR JCALLSWORTH y gwnmarb, {md/m Wfgs July 7, 1964 J. DELANEY ETAL INERTIA RESPONSIVE FuzE 6 Sheets-Sheet 2 Filed March 7, 1963 Attorneys- H m Nw v 1 mu x D ABM H N H f T m wmfn) mw V AM, l I W m h w ML.

lll bwl mm mm om July 7, 1964 Filed March '7, 1963 J. DELANEY ETAL INERTIA RESPONSIVE FUZE 6 Sheets-Sheet 3 .F/GJ. @I ,2 ,8

Inventors A ltarneys July 7, 1964 J. DELANEY ETAL INERTIA RESPONSIVE FUZE 6 SheebS-Sheeb 4 Filed March 7, 1963 nl r JOHN DELI Vl CTOR HALLSWORTH By i mw Kga/M Y ttorney July 7, 1964 J. DELANEY ETAL INERTIA RESPONSIVE FuzE 6 Sheets-Sheet 5 Filed March 7, 1963 Inventors JOHN :DEL ANEY VICTOR HALLSWORTH By @wma/wn, MAa/m, YMW

July 7, 1964 J. DELANEY ETAL 3,139,828

v INERTIA RESPONSIVE FUZE Filed March 7, 1963 6 Sheer,s-SheerI 6 F/G/Z..

Ltr mmnlors d O HN DE LANEY f\| V lCTOR HA L LSWORT H e L A tlorneys United States Patent O 3,139,828 INERTIA RESPONSIVE FUZE John Delaney, Oldham, and Victor Hallsworth, Ashton under Lyne, England, assignors to Ferranti, Limited, Hollinwood, England, a company of Great Britain and Northern Ireland Filed Mar. 7, 1963, Ser. No. 263,528 Claims priority, application Great Britain Mar. 8, 1962 6 Claims. (Cl. 102-78) This invention relates to missile fuze arming devices and is particularly, although not exclusively, concerned with fuze arming devices suitable for use with rocket powered missiles.

It is an object of the present invention to provide a missile tuze arming device which is certain in operation but which is safe from accidental shocks caused during handling of the missile prior to tiring.

According to the present invention a missile fuze arming device includes a weight slidably mounted on a base adapted to be fixed with respect to the missile, said weight being biassed to a safe position, a detonator carrier slidably mounted on said base and separated from said weight by a barrier xed with respect to said base, said detonator carrier being mechanically connected to said weight by resilient means passing through said barrier, and means for controlling the rate of movement of said detonator carrier, the arrangement being such that accelerational forces acting on said weight when said missile is tired are transmitted to said detonator carrier through said resilient means to move said detonator carrier, said detonator carrier being moved to an armed position if said accelerational forces have a magnitude greater than a desired minimum value and act for a minimum time predetermined by said means for controlling the rate of movement of said detonator carrier.

lSaid device may further include means for preventing the return of said weight to the safe position after accelerational forces of a desired minimum magnitude have been acting for said predetermined time.

One embodiment of the present invention will now be described by way of example with reference to the accompanying drawings in which:

FIGURE 1 is a plan view of a missile fuze arming device in accordance with the invention,

FIGURE 2 is a side elevation of the fuze arming `de 'vice shown in FIGURE 1,

FIGURE 3 is a section along the line 3-3 in FIG- URE 2,

FIGURE 4 is a section along the line 4-4 in FIG- URE 2,

FIGURE 5 is a simplied side elevation showing a modiiication of the fuze arming device shown in FIG- URE 1, j

FIGURE 6 is a section along the line 6 6 of FIG- URE 5, i

t FIGURE 7 is a section along the line 7--7of FIG- URE 5,

FIGURE 8 is a side elevation of the device shown in FIGURE 5 during the boost period,

FIGURE 9 is a section along the line 9-9 of FIG- URE 8, j j FIGURE 10 is a section along the line 10-10 of FIG- URE 8,

FIGURE 11 is a side `elevation vof the device shown in FIGURE 5 at the end of the boost period,

FIGURE 12 is a section along the line 12-'12 of FIG- URE 11, and

FIGURE 13 is a section along the line 13-13 of'FIG- URE 11.

Referring now to FIGURES 1 to 4 of the drawings the missile fuze arming device shown includes a base 1 on Fice which are mounted

end plates

2 and 3 and a central barrier 4. Two rods 5 and 6 extend between the

end plates

2 and 3 and a further rod 7 extends between the end plate 2 and the barrier 4. A weight 8 is slidably mounted on the

rods

5, 6 and 7 for movement between the end plate 2 and the barrier 4, and a detonator carrier 9 is slidably mounted on the rods 5 and 6 for movement between the barrier 4 and the end plate 3. The weight 8 is biassed towards the end plate 2 by means of two compression springs 10 and 11 mounted on the rods 5 and 6 and recessed into the weight 8 and the barrier 4. A rod 12 is rigidly secured to the detonator carrier 9 and extends through the barrier 4 and passes freely through an aperture in the weight 8. A compression spring 13 is mounted on the rod 12 and extends between the detonator carrier and the near side of the weight 3 passing freely through the barrier 4, and a further compression spring 14 is mounted on the rod 12 and extends between the inner wall of a recess 15 in the weight 8 and an abutment formed by a screw 16 threaded into the end of the rod 12.

The detonator carrier 9 has a detonator 17 secured by two screws 18 and carries electrical contacts 19 which co-operate with contacts 2t) and 21 mounted on a platform 22 fixed with the respect to the base 1. The platform 22 carries an igniter 23 connected to an electrical tiring circuit by means of contact 24 which co-operates with a further contact on the inside of a cover member (not shown). In order to regulate movement of the detonator carrier 9 it is provided with a rack 25 which cooperates with a gear train 26 to drive anescapement including a pallet 27.

The detonator carrier 9 is also provided with a groove 28 extending along one side and having a short vertical groove 29 forming an outlet near one end. An arm 30 projecting transversely from a rod 31 rides in the groove 28. The rod 31 extends between the end plate 2 and the barriei 4 and projects beyond barrier 4. A spring 32 biasses rod 31 to rotate in the direction of the arrow shown in FIGURE 3. In the safe condition the rod 31 is prevented from rotating by means of a stop in the form of a quadrant 33 which engages with a projection 34 extending along the full length of the weight S, the quadrant 33 being mounted on the rod 31 in such a position that when the weight 8 is against the barrier 4 the quadrant 33 is just clear of the forward end of the projection 34.

In operation the arming device is mounted in the missile with the rods 5 and 6 parallel to the accelerational axis. When the missile is tired, if the accelerational forces have a magnitude greater than a desired minimum value determined by the springs 10 and 11 the weight Sis caused to move 'back against the action of the springs 10 and 11 until it is prevented from further movement by the lbarrier 4. The spring 13 is therefore compressed and causes the detonator carrier 9 to move backwards, the rate of this movement being controlled by the gear train 26 and the escapement. With the weight 8 against the barrier 4 to quadrant 33 is freed from the projection 34, but the rod 31 is prevented from rotating until the detonator carrier 9 has moved suiiciently far for the arm 3i) to be freed upon reaching the vertical groove 29, the time taken for the detonator carrier to travel this distance being predetermined by a suitable choice of eS- capement. Thereafter the rod 31 rotates for a quarter of a turn and the quadrant 33 is then in such a position as to prevent the return of the weight 3. The detonator carrier 9continues moving due to the compression of the spring 13 and just prior to the carrier 9 reaching the armed position the rst pinion in the gear train 26 runs oit the rack 23 so that the detonator carrier`9 suddenly moves into the armed position and the contact 19 engages the contact 21 to complete the electrical tiring circuit. In this position the igniter 23 and the Vdetonator 17 are in line with a chemicallyy explosive pellet (not shown) contained in an aperture 35 in the base 1.

It Will be seen that the gear train 26 is protected from accidental shock loads imposed on the weight 8. If the weight 8 is moved towards the barrier 4 the spring 13 prevents the shock from being transmitted to the gear train 26 and should the weight 8 be suddenly returned towards the end plate 2 the spring 14 similarly prevents the shock from being transmitted to the gear train 26. In order to arm the missile the Weight 8 must be held against the barrier 4 for a sufficient time to elapse such that the detonator carrier 9 moves to bring the vertical groove 29 in line with the arm 30. This time may be made of any required length by suitably choosing the escapement 27 and a suitable length of time is 21/2 seconds. Also, unless the acceleration reaches the minimum value required the mechanism will not arm since the weight 8 will not have sufficient force to fully compress the springs and 11 and hence will not reach the barrier 4. The quadrant 32 will therefore be prevented from rotating by the projection 34 and the arm 30 will prevent ythe detonator carrier 9 from moving into the armed'position. The missile is therefore fully protected from accivdental shocks caused during handling and, furthermore, will not arm until the missile has travelled a safe distance from the firing point.

In the fuze arming device described above the detonator carrier 9 is moved to the armed condition at a fixed time after firing, the time being determined by the gear train 26 and the escapement. In some missiles, however, the boost period during which the missile is being accelerated varies with the ambient temperature and if the missile becomes armed at a xed time after firing the arming distance will similarly vary with the ambient temperature.

train and escapement and the components of the electrical firing circuit have been omitted. The device differs from that described above in that the rod 31 is provided with a quadrant 40 which is positioned such that when the weight 8 is against the barrier 4 the quadrant 40 is well clear of the forward end of the weight 8. The rod 31 is also provided with a stop 41 positioned adjacent the barrier 4. The Weight 8 has a projection 42 which co-operates with 'the quadrant 40 to prevent rotation of the rod 31 during the intermediate stage of the travel of the weight 8.

Before firing the conditions are as shown in FIGURES 5, 6 and 7, the rod 31 being prevented from rotating by the engagement of the arm 30 in the groove 28 in the detonator carrier 9. When the missile is fired accelerational forces having a magnitude greater than the desired minimum value cause the weight 8 to move back to the barrier 4 and the detonator carrier 9 is moved back in the manner previously described until the arm 30 reaches the groove 29 as shown in FIGURE 8. The rod 31 then rotates until the stop 41 engages the weight 8 (FIGURE 9) to prevent the release of the arm 30 from the groove 29 (FIGURE 10). The arm 30 therefore effectively locks the detonator carrier 9 during the boost period. At the end of the boost period the weight 8 starts to move forward under the action of the springs 10 and 11 (FIG- URE 1. As the weight 8 moves forward, however, the stop 41 is released and the rod 31 rotates and positions the quadrant 40 such that it prevents further forward movement of the weight 8 (FIGURE 11). Rotation of the rod 31 also releases the arm 30 from the groove 29 (FIG- URE 13) andthe detonator carrier 9 is then moved to the armed position as previously described. In this manner thermissile becomes armed at the end of the boost period iand not at a fixed time after firing.

The total boost delivered to the missile is constant and may be delivered at a high rate for a short time when the ambient temperature is high `or at a slower rate for a longer time when the ambient temperature is low but by delaying the arming of the missile until the end of the boost period the variations of the distance travelled by the missile before it is armed due to variations of the ambient temperature are considerably less than Yif the missile is armed at a fixed time after firing. I

What we claim is:

1. A missile fuze arming device including a base adapted to be fixed with respect to the missile, a weight mounted on said base for longitudinal slidable movement relative thereto parallel to the accelerational axis of the missile from a safe position to an arming position, biassing means for biassing said weight to` said safe position, a vdetonator carrier mounted on said base for longitudinal slidable movement relative thereto parallel to the accelerational axis of the missile from a safe position to an armed position, a barrier fixed with respect to said base between said weight and said detonator carrier for preventing direct mechanical contact between said weight and said detonator carrier, resilient coupling means passing through said barrier for resiliently coupling said weight to said detonator carrier irrespective of the direction of `movement of said Weight, delay means for controlling the and said detonator carrier has moved to a predetermined position intermediate its safe and armed positions.

2. A missile fuze arming device as claimed in claim 1 including means for preventing said detonator carrier from moving to its armed position when subject to an accelerational force having a magnitude greater than the minimum force required to overcome said biassing means and move said weight to its arming position.

3. A missile fuze arming device as claimed in claim 1 in which said stop means includes a rod rotatably mounted on said base having first and second transverse projections, means biassing said rod to rotate in sucha direction as to move said first transverse projection into the path of said Weight, a groove extending lengthwise of said detonator carrier and adapted to receive said second transverse projection to prevent rotation of said rod, and an outlet from said groove so positioned that said second transverse projection may be released from said groove to permit rotation of said rod by said biassing means when saiddetonato'r carrier reaches said predetermined position. l 't 4. A missile fuze arming device as claimed in claim 3 in which said rod is also provided with a third transverse projection adapted to so engage said weight when said weight is in its arming position as to permit only par- Vtial rotation of said rod toan extent such that said second Athan the minimum force required to overcome said biassing means and move said weight to its arming position, said first transverse projection being so positioned as to allow sufficient forward movement of said weight to release said third transverse projection when said accelerational force falls to a magnitude less than said minimum force, thereby permitting release of said ysecond trans- 3,139,828 5 verse projection and continued movement of said det- References Cited in the le of this patent onator carrier towards its armed position. UNITED STATES PATENTS 5. A missile fuze arming device as claimed in claim 1 714,540 Great Britain Sept. l, 1954

Claims

1. A MISSILE FUZE ARMING DEVICE INCLUDING A BASE ADAPTED TO BE FIXED WITH RESPECT TO THE MISSILE, A WEIGHT MOUNTED ON SAID BASE FOR LONGITUDINAL SLIDABLE MOVEMENT RELATIVE THERETO PARALLEL TO THE ACCELERATIONAL AXIS OF THE MISSILE FROM A SAFE POSITION TO AN ARMING POSITION, BIASSING MEANS FOR BIASSING SAID WEIGHT TO SAID SAFE POSITION, A DETONATOR CARRIER MOUNTED ON SAID BASE FOR LONGITUDINAL SLIDABLE MOVEMENT RELATIVE THERETO PARALLEL TO THE ACCELERATIONAL AXIS OF THE MISSILE FROM A SAFE POSITION TO AN ARMED POSITION, A BARRIER FIXED WITH RESPECT TO SAID BASE BETWEEN SAID WEIGHT AND SAID DETONATOR CARRIER FOR PREVENTING DIRECT MECHANICAL CONTACT BETWEEN SAID WEIGHT AND SAID DETONATOR CARRIER, RESILIENT COUPLING MEANS PASSING THROUGH SAID BARRIER FOR RESILIENTLY COUPLING SAID WEIGHT TO SAID DETONATOR CARRIER IRRESPECTIVE OF THE DIRECTION OF MOVEMENT OF SAID WEIGHT, DELAY MEANS FOR CONTROLLING THE RATE OF LONGITUDINAL MOVEMENT OF SAID DETONATOR CARRIER, STOP MEANS MOUNTED ON SAID BASE AND COOPERATING WITH BOTH SAID WEIGHT AND SAID DETONATOR CARRIER, SAID STOP MEANS HAVING A FIRST POSITION, IN WHICH SAID WEIGHT AND SAID DETONATOR CARRIER ARE BOTH FREE TO MOVE, AND A SECOND POSITION, IN WHICH SAID WEIGHT IS PREVENTED BY SAID STOP MEANS FROM RETURNING TO ITS SAFE POSITION AND SAID DETONATOR CARRIER IS STILL FREE TO MOVE, AND MEANS OPERABLE TO MOVE SAID STOP MEANS FROM SAID FIRST POSITION TO SAID SECOND POSITION WHEN SAID WEIGHT IS IN ITS ARMING POSITION AND SAID DETONATOR CARRIER HAS MOVED TO A PREDETERMINED POSITION INTERMEDIATE ITS SAFE AND ARMED POSITIONS.