Patent GB-110046-A (GB)
Title: Improvements in or relating to Means for Relay Transmissions of Directive Angular Movements.
Inventor: GILLMOR REGINALD EVERETT
IPC: G01C19/40
Filed: 1916-11-08
Abstract: 110,046. Gillmor, R. E., (Sperry Gyroscope Co.). Nov. 8, 1916. Gyroscopic compasses. - The movements of a gyroscopic compass are transmitted to indicating or repeating instruments by means of a follow-up member, which is maintained in a constant state of oscillatory motion between narrow predetermined limits to reduce friction, and controls transmission apparatus adapted to transmit only such movements of the follow-up member as exceed these limits. The directive element 1 carries two contacts 8 which cooperate with pairs of contacts 10, 11 on the follow-up member 2. The contacts 8. 10, 11 are arranged to control a reversible motor 20 which normally oscillates the follow-up member 2 and also serves to restore the normal relative positions of the parts 1, 2 when the ship turns. The transmitter 50 of the electric signalling system, which is not affected by the normal oscillations of the follow-up member, comprises a hunting-switch 60, one member of which is driven by the followup member 2 and the other by a second reversible motor 69, the arrangements being such that when one member oi the hunting-switch is moved through an angle greater than that due to the normal oscillations of the follow-up member, circuit is closed in one or other direction through a third reversible motor 73, Fig. 9, which drives the transmitter proper 174 or 175 is a corresponding direction so as to transmit the necessary currents to the distant repeaters 84, 120 and also to the second motor 69 which drives the other member of the hunting-switch. The transmitter proper may comprise two or more transmitters 174, 175 operating at different speeds so as to control repeating instruments giving indications of different degrees of fineness. Means for controlling movement of follow-up member. The follow-up member 2 is driven through gear 28 and reduction gearing 33, 32, 30 from the reversible motor 20 which is controlled directly by the contacts 8, 10, 11 or through a relay 21, 22. The movement of the member 2 in one direction or the other causes the contact 8 to engage contact 10 or 11, thus supplying current to the winding 22 or 21 of the relay, which closes the circuit of one or other of the differential field coils 25 so as to reverse the motor, thus moving the follow-up member in the other direction. A switch 100 enables the relay to be disconnected, the necessary circuits to change the control of the motor being made and broken automatically by the removal of the relay. The armature of the motor 20 is connected in series with a clutch magnet 34 so that if the supply current fails the motor shaft is disconnected from the follow-up member 2. In order to reduce shock due to the quick oscillation of the motor shaft, a small flywheel loosely mounted on the shaft rests on the friction face of a collar pinned to the shaft. Construction and operation of transmitter. As previously stated, the motor-driven transmitter is controlled by a hunting-switch which comprises a brush driven through gearing 71 by the motor 69 and a plate having segmental contacts 61, 62 separated by insulation 63<1> which is tapered outwardly. The brush is formed with a contact tapered to correspond with the insulation 63<1> and is radially adjustable. The brush rests on the insulation 63<1> during the normal oscillatory movement of the follow-up member 2, but when the ship turns, circuit is closed through contact 61 or 62 through the corresponding field winding 74, 75 of a reversible motor 73 which drives the transmitter proper. Two transmitters are shown, one 174, driven at a slow speed, carrying a series of cams 80 which operate springs 82 in succession so as to control the distant indicator 84 in known manner. The other transmitter 175, driven at a higher speed, comprises a three-section rotary commutator, each section being associated with a mechanical interrupter so arranged that the circuit is broken twice for each revolution of the commutator, a quick non-sparking break occurring at the contacts of the mechanical interrupter. The currents thus produced are transmitted to the distant indicator 120 and also to the reversible motor 69 which through gearing 70, 71 drives the brush 64 of the hunting-switch so as to bring it back to its normal resting position in which the circuit of the motor 73 is opened and the transmitter arrested. Current supply and alarm circuits. The motor 103 driving the gyroscope is supplied from a three-phase circuit, and the other motors and circuits for signalling purposes from direct-current mains d c and a storage battery 105 connected through a reverse current relay 106 in known manner to the mains, so that if the supply fails the battery cannot discharge through the mains. A contact 107 closes the circuit of an alarm relay 112 controlling a bell 111. The alarm relay is also connected in circuit with contacts 108, 109, Fig. 9, respectively carried by the directive member 1 and the follow-up member 2 so that the circuit is closed if the member 2 fails for any cause to follow up the movement of the member 1.