Patent GB-639787-A (GB)
Title: Remote control and indicating system
IPC: G05D3/12
Filed: 1947-07-10
Abstract: 639,787. Automatic speed control systems. BENDIX AVIATION CORPORATION. July 10, 1947, No. 18351. Convention date, Aug. 22, 1946. [Class 38 (iv)] [Also in Group XXXVIII] A system for positioning a remote mechanism from a control station, comprises a motor, the energizing circuit of which includes a first commutator driven by a rotatable driving means and a second commutator driven by the motor, the alternate conducting segments of each commutator being connected together to form a plurality of conductive units at each commutator, the corresponding units being connected together. The Figure shows the element at a control station, including driving handle 10 and indicator 89, and at the remote station including the controlled element 28. At the control station, rotation of crank 10 rotates a mechanical switch 12 and commutator 16, a flexible member 31 being provided which contacts one or other of the terminals 46, 42 according to the direction of rotation of crank 10. A direct current motor 18 at the remote station drives commutator 22 through a magnetic clutch and brake mechanism 20 (which may be of the type described in U.S.A. Specification 2,267,114) which is controlled by the motor current flowing through coil 15. The armature and field current of motor 18 is supplied from lead 13 via commutators 22 and 16 which are connected by leads 51, 52 and switch 12. Rotation of crank 10, and therefore of commutator 16, results in an impulse of current to the motor through one or other of the opposing parts of coil 17, so that the motor and commutator 22 rotate in the required direction. The connections between the segment of the commutators are so arranged that impulses of current to operate the motor and clutch 20 and to release the brake, are provided whenever one commutator rotates relative to the other, so that synchronism is established. Commutator 22 is mechanically connected to a mechanism 28 which is thus under the control of crank 10. Various gear ratios may be provided in the mechanical links, and the ratio of the members of segments in the two commutators may be varied so that any desired speed relation between crank 10 and mechanism 28 can be obtained. Mechanism 28 may be a condenser which is slowly rotated when crank 10 is turned. If crank 10 is rotated at an excessive speed, a limit switch 24, which, operates when commutator 22 rotates at a predetermined speed, shorts leads 51, .52, so that the motor is then continuously excited, and it will continue at this speed until crank 10 is released, or moved in the opposite direction, so that member 31 becomes disconnected from the contact (42 or 46) which was in use, thus breaking the motor circuit. Means are also provided for indicating the position of the controlled mechanism 28 at the controlling station. Commutator 30 which is driven by motor 18 is connected by leads 81, 82, 83, 84, to commutator 40 which is driven by a motor 34, through a clutch and brake mechanism 36. When commutator 30 rotates, a current impulse is supplied to motor 34 either via brush 72 or 74 according to the direction of rotation, the arrangement being somewhat similar to that previously described so that commutator 40 is rotated in synchronism with commutator 30. A pointer 89 is mechanically connected through any desired gear ratio, to commutator 40, so that the position of mechanism 28 may be indicated at the control station. A warning indicator 92 is also provided which is controlled by a solenoid 79. Solenoid 79 is normally energized via one of the brushes 72, 73 or 74, for " neutral " or " impulsing " positions of commutator 40, but if lack of synchronism occurs so that the current supply is connected to the isolated segment in position 70, the solenoid is de-energized, so operating the warning indicator.