Patent GB-967188-A (GB)
Title: Improvements relating to missile fuze arming devices
Inventor: DELANEY JOHN
IPC: F42C15/184
Filed: 1962-03-08
Abstract: 967,188. Ammunition fuzes. FERRANTI Ltd. March 7, 1963 [March 8, 1962], No. 9046/62. Heading F3A. A fuze arming device, particularly for use with selfpropelled missiles, comprises a weight 8 connected by resilient means to a detonator carrier 9 and slidably mounted in the fuze, so that when the missile is launched, due to acceleration, the weight tends to move the carrier to the armed position. Furthermore, means are provided for controlling the rate of movement of the carrier in such a way that if the acceleration exceeds a predetermined minimum value and continues for a minimum time the carrier arrives at the armed position. The weight 8 is mounted on rods 5, 6 extending between end plates 2, 3 and passing through a barrier 4 and carrier 9, a further rod 7 passing through the weight 8 having its ends supported by the plate 2 and barrier 4. In its position of rest the weight 8 is supported by two springs 10, 11 surrounding the rods 5, 6 respectively and extending into recesses in the barrier 4. A rod 12 secured to the carrier extends through the barrier 4 and through a hole in the weight 8, the rod 12 being surrounded by compression springs 13 and 14 the latter spring being in abutment with a recess 15 and a screw 16. These springs 13, 14 are to protect a gear train 26 against accidental shock loads on the weight 8. After launching the missile, when the acceleration reaches a minimum value determined by the springs 10, 11, the weight 8 sets back and compresses the spring 13 thereby causing the carrier 9 to move rearwardly, the rate of movement being controlled by a rack 25 in mesh with the gear train 26 which drives an escapement provided with a pallet 27. A rod 31 carries an arm 30 engaged in a groove 28 extending along the side of the carrier 9 and when the carrier has moved sufficiently for the arm 30 to reach a continuation 29 of the groove 28 the rod 31 rotates bringing a quadrant 33 carried by the rod into the path of the weight to prevent its return by the springs 10, 11. The carrier 9 continues to move due to the action of spring 13 and just before the carrier reaches the armed position the rack and gears become disengaged. The carrier then moves suddenly to the armed position in which the detonator 17 is aligned with a pellet housed in a recess 35, electric contacts 19, 21 then being in position to complete the firing circuit. A modification, Fig. 5, is provided in which arming occurs at the end of the boost period and not at a fixed time after launching. In this the rod 31 carries a quadrant 40 which is well clear of the forward end of the weight 8 when the weight abuts the barrier 4. The rod 31 also carries a stop 41. When the arm 30 reaches the groove 29, the rod 31 rotates until stop 41 engages the weight 8 and so prevents release of the arm 30 from the groove 29. The carrier 9 is thus locked until the end of the boost period, when the weight 8 starts to move forward due to springs 10 11. Stop 41 is then released and the rod 31 rotates further bringing the quadrant 40 into the path of the weight. The arm 30 then releases the carrier 9, which moves as before to the armed position.