GB390051A - Improvements in or relating to hand electric steering gear for dirigible crafts - Google Patents

Abstract

390,051. Control of motors. SPERRY GYROSCOPE CO., Inc., Manhattan Bridge Plaza, Brooklyn, New York, U.S.A.- (Assignees of Hodgman, F. S.; 111, Valley Road, Glen Rock, New Jersey, U.S.A.) Aug. 12, 1932, No. 22686. Convention date, March 26. [Class 38 (iii).] A combined hand and electric steering-gear for ships and aircraft is arranged with a lost motion connection between the engine control and the wheel, whereby the wheel on initial hand turning can bring the engine into operation whilst a followback connection normally stops the engine when the wheel is stationary. The hand-wheel 1 is adapted to move a shaft 9 which is geared to the shaft 16 operating the cable drum 18 and cable 19 which actuates a rudder 20. The drum 18 is also adapted to be operated by gears through a magnetic clutch 42 from an electric motor 21. In the pedestal 2 the drive from the wheel is by gear-wheels 4, 5 to a shaft 6 carrying a dog clutch 7. An intermediary dog clutch 10 gears in turn with a dog clutch 14 secured to the shaft 9. These dog clutches are provided with spaces which give a lost motion and may be faced with felt to reduce noise. In the ordinary way hand steering would be effected through these dog clutches. The dog members 7 and 14 however each carry spur-wheels 22, 25 engaging nuts 23, 26 respectively in which operate a rod 28 which screws into the lower nut 26 and is slidingly splined in the upper nut 23. This rod 28 has a collar engaged by a pivoted member 32, the end 34 of which is adapted to make contact with contact points 35, 36 in the electric motor circuit. On the turning of the hand-wheel therefore, there will be a relative motion of the spur-wheels 22, 25 which will result in a longitudinal motion of the rod 8 whereby contact will be made and the motor started. At the same time the magnetic clutch 42 is energized and the motor will rotate the cable drum 18. For the follow-up mechanism, spur wheels 45 are employed. In order that the hand wheel need not be continuously rotated in order to produce rudder motions, relays may be imposed in the motor circuit, the magnetic relays 49, 50 completing the circuit between contacts 51, 151, 52 and 152 to send a current through the motor armature 53 in the required direction and also through the series field 54. When the respective relays are de-energized, they establish back-contacts 55, 55<1>, and cause dynamic braking by shortcircuiting the armature through resistance 56. Limit switches 57, 57<1> are provided to limit the throw of the rudder in each direction. In addition to dynamic braking an electromechanical brake 61 is also provided for the motor shaft. In order that continuance of the operation may be ensured, one of the members 11 of the dog 10 is provided with springs 66 having roller ends 69 which are adapted to snap into and out of engagement with the faces 8 and one of the other dog members.