Patent GB-616517-A (GB)
Title: Improvements in and relating to control systems for power driven movable objects
IPC: G05D3/14
Filed: 1942-01-31
Abstract: 616,517. Electric control systems. TUSTIN, A., and METROPOLITAN-VICKERS ELECTRICAL CO., Ltd. Jan. 31, 1942, No. 1330. [Class 40 (i)] In a control system for a power-driven object movable about two axes, e.g. a gun mounted in a rotatable turret, movement about one axis (training) occurs at a speed dependent on the position of a control member, whereas movement about the other axis (elevating) is determined by a sighting device through positional follow-up control means. As shown in Fig. 1, the turret 2 is trained by an electric motor 4 and gearing 5 ... 8 at a speed determined by the position of control handle 20 and the torque of the motor may have components depending on the speed and acceleration of the movement of the control handle as described in Specifications 577,309 and 577,315, [both in Group XXXVII]. The gun 1 is elevated by electric motor 9 controlled by follow-up means 17 from a shaft 13 carrying a sighting device 12 positioned by a handle 15 located for operation by the right hand of the gunner who controls the turret member 20 with his left hand. The control may take into account the velocity and acceleration of the sighting device and velocity of the gun. Metadyne or Ward-Leonard systems may be used or the driving motors may be hydraulic, control being effected by suitable relays responsive to the electric control systems. Variable velocity transmission may be utilized. The controls may include gyroscopic stabilization as described in Specification 616,516, and amplifiers such as the vibrating regulators described in that Specification may be provided, Positional follow-up elevating controller, Fig. 2. Two two-element resilient finger resistance controllers 22, 23 as described in Specification 577,312, [Group XXXVII], are employed. One element of each controller is geared to the shaft 13 of the sighting device, the other element 27 of controller 22 being connected through a spring coupling 43 (Specification 577,489, [Group XXIV]) to a shaft 44 geared to the elevating shaft 18 of the gun. Controller 22 is the positional follow-up controller. The other element 28 of controller 23 carries a disc 51 subject to magnetic or other damping so that its output has a component dependent upon the velocity at which the sighting device is moved. Inertia and friction in the controller introduce a component dependent on acceleration and a component that may compensate friction at the gun mounting. The spring coupling 43 is arranged so that for small displacements or torques the coupling is rigid, but yields after the controller has been operated through a portion of its control range. Subsequently, when the controller has operated through its full range, no increase in output is obtained for further increase of torque. Control circuits, Fig. 4. The training motor 4 controlled by a metadyne machine 60 and controller 19 by handle 20 is arranged substantially as described in Specification 577,315. The elevating motor 9 is controlled by metadyne machine 61 driven in common with the training metadyne and having its variator winding 74 connected to the outputs, in parallel, of the follow-up controller 22 and of the controller 23 which introduces velocity &c. components of the sighting device. The velocity of the gun in elevating is taken into account by applying the armature voltage of motor 9 to an auxiliary variator winding 75, resistance 83 being cut out by limit switches on the gun similar to the arrangement in the training control circuit. The arrangement is preferably such that when the sighting device and gun are moving at the same velocity in the same direction, the velocity component due to controller (sighting) balances the velocity component due to the driving motor. In a Ward-Leonard system, back E.M.F. directly provides the velocity component. Gyroscopic stabilization of the training movement including stabilization against crossroll may be effected as described in Specification 616,516. Stabilization of the elevating movement is effected by stabilizing the sighting device 12 as shown in Fig. 5. Motor 103 is controlled by a gyroscope similarly to the gun driving motors in Specification 616,516 and the motor drives one sun pinion 102 of a differential gear, the other sun pinion 100 being fixed on the shaft of the sighting device. The control lever 15 and motor operate on their respective sun-wheels through irreversable gearing 105, 106, the gearing between lever 15 and sight 12 being brought back to a 1 to 1 velocity ratio by gears 107, 108. The planet gears 104 pass on the resultant to the controller 17 which operates as previously described.