GB1097038A - Improvements relating to jet-propulsion motors - Google Patents

Abstract

1,097,038. Thrust vectoring apparatus. BRITISH AIRCRAFT CORPORATION (OPERATING) Ltd. Dec. 1, 1964 [Dec. 3, 1963], No. 47722/63. Heading B7G. A jet propulsion engine (a rocket motor, as described) has, immediately behind its discharge nozzle 2, a jet deflector comprising a plate 10 with a central aperture coaxial with the discharge nozzle when in the neutral position. The deflector plate is restrained by a number of parallel flexible wires 12 extending forwards from the plate to anchorages on the motor. The plate is also movable laterally with respect to the nozzle to deflect the jet by two pairs of diametrically opposed electromagnets 36 acting through bell-cranks 42, links 22 and a ring 24 brazed to the plate. The electromagnets of each pair are energized alternately, e.g. at 20 cycles/ sec., and the mean position of the plate, and hence the mean direction of the thrust vector, is varied by varying relatively the times the electromagnets are energized. This may be done by feeding a triangular signal (70c, Fig. 6A, not shown) and a bias current (D1) to a bi-stable device which has square-wave outputs (70a and 70b) to be supplied to opposed electromagnets, and the relative periods of energization is varied by varying the bias current (D1). Each electromagnet has a switch operated by a screw 60 on the armature 40 engaging an actuator 62 to introduce a resistor into its circuit to reduce the current when the armature reaches the solenoid. A heat shield 28, made for example of molybdenum, is provided, and the deflector plate may be made of molybdenum or tungsten. In another embodiment (Fig. 8, not shown), the deflector plate (86) is made of, or attached to magnetic material and is disposed between polepieces (84), on which solenoids (80) are mounted.