Patent GB-130162-A (GB)
Title: Improved Method of and Apparatus for Electrically Operating Mechanisms from a Distance.
Inventor: BLOXAM ARTHUR GEORGE
IPC: F41G3/14
Filed: 1918-07-26
Abstract: 130,162. Bloxam, A. G., (Ericsson & Co., L. M.). July 26, 1918. Distant - control systems and apparatus; order and order-type apparatus.-A system for the synchronous operation of a number of mechanisms, and particularly applicable to gun-fire control, comprises a number of step - by - step motors operated by alternating or pulsating current, one or more controlling stations, and a single relay controlling the circuits of the motors in such a manner that these circuits are broken at a period of no-current. Each motor is provided with two similar electro-magetic systems, the armatures of which operate separately through a differential gear to determine the direction of rotation of the mechanism. In a system employing alternating current, each etectro-magnet is provided with a direct-current winding continuously energized and an alternating current winding adapted to be placed across one phase of a three-phase supply system of the relay. The ampere turns of the direct current winding are sufficient to keep the motor armature attracted, and the armature is oscillated by the superposition of the ampere-turns of the alternating current winding. The relay controlling the motor circuits is divided into two similar parts each of which is provided with a continuously energized direct-current winding and a continuously energized alternating-current winding placed across a diffesent phase of the alternating-current source from that of the motor windings. Each part of the relay is operated by short-circuiting a resistance in series with its direct-current winding, and the operation of one part opens a switch in the short-circuit of the other in order that both parts may not be operated at the same time. The relay is controlled by a hunting or differential switch at the transmitting station. In a pulsating-current system, the motor is provided with a single winding and the controlling relay with a direct current winding and an opposing pulsating-current winding both of which are normally energized, and an assisting pulsating-current winding, the circuit of which is controlled by the transmitter switch. Step-by-step motors. The reversible step-bystep motor, operated by alternating current, comprises two electro-magnets 24 and 25, Figs. 8 and 9, the armatures 26 and 27 of which are mounted on pivots 28, 29 and are withdrawn from the magnet cores by flat springs 34, 35 bearing upon projections 32, 33. The armatures 26, 27 are provided with projections 38, 39 upon which are pivoted the operating pawls 40, 41 which engage ratchet-wheels 44, 45 mounted loose upon a shaft 54. The wheels 44, 45 are provided with retaining pawls 46, 47 and are connected to the wheels 52, 53 of a differential gear, the planet wheels 56 of which are mounted upon an arm 55 secured to the shaft 54, the direction of rotation of which is controlled by energizing the magnet 24 or the magnet 25. The magnets 24, 25 are provided with a winding 19, Fig. 10, continuously energized from a direct current source, and the ampere-turns of this winding are sufficient to keep the armatures 26, 27 attracted against the action of the springs 34, 35 but are not sufficient to attract the armatures fully. The magnets 24, 25 are provided each with a winding 20 adapted to be selectively energized from the phase I, II of a three-phase supply I, II, III by a relay 2 to operate the shaft 54 in one direction or the other. The superposition of the ampere-turns of the winding 20 upon the ampere-turns of its winding 19 causes the armature of these windings alternately to be attracted and retracted and the re- , lay 2 is so arranged that the circuit of the windings 20 of the various motors of the system is made at a period of no-current in order to avoid sparking at the relay contacts. The step-by-step motor, operated by pulsating current, comprises two electro-magnets, one of which 24 is shown in Fig. 28. The armature 26 of the magnet 24 is normally retracted by a spring 34 and carries a pawl 40 which engages a ratchet-wheel 44. Each magnet is provided with a single winding, and these windings are selectively connected to the leads I, II or I, III, Fig, 27, connected to a source of pulsating current by a relay 2 at a period of no current. Relays. The relay 2 controlling the motors operated by alternating current consists of two similar parts, one of which is shown in Figs. 12 and 13 and both of which are shown diagrammatically in Fig. 15. The armature 63 of the magnet 62 is normally held against a stop 66 by an adjustable spring 67 and carries an insulated member 70 and a contact member 69. The parts of the relay are provided with windings 77 and 78 respectively connected to a direct-current source, and windings 75 and 76 connected in series across the phase I-III of the three-phase mains I, II, III. The windings 77, 78 are normally in series with resistances 79, 80 respectively, adapted to be separately shortcircuited by a switch 81. The short-circuits about the resistances 79, 80 contain switches 71, 72 so arranged that, when one part of the relay is operated, its member 70 opens the switch 71 or 72 of the other part in order that both parts may not be operated at the same time. Normally, the ampere-turns of the wmding 77, when connected in series with its resistance 79, and the ampere-turns of the winding 75 are not sufficient to operate the relay, but upon the short-circuiting of the resistance 79 by the switch 81 the ampereturns of the windings 77 and 75 are sufficient to actuate the relay to cause the contacts 73, 74 to be bridged by the contact 69 and to open the switch 72 in the short-circuit about the other resistance 80. One contact 69 connects one of the windings 20 of a number of step-by-step motors 1, Fig. 1, to the phase I-II of the threephase supply I, II, III, while the other contact 69 connects the other windings of the motors 1 to the phase I-II for the reverse operation of the motor. The tensions of the springs 67 are adjusted so that the motor circuits are broken when the current supplied to them is zero or approximately zero. A relay 2, Fig. 27, controlling the motors operated by pulsating current, is similar in construction to that described above but is provided with a winding 151 continuously energized from a direct-current source, a winding 152 opposing the winding 151, and continuonsly energized from the leads I, III of a pulsating source of current, and a third winding 153 assisting the winding 151 and adapted to be connected across the leads I, II by a switch 3. The circuits of the windings 153 contain switches 71, 72 so arranged that when one part of the relay is energized by its winding 153 the other part cannot be energized by its similar winding. The ampere-turns of the windings 151, 152 and 153 are so arranged that the relay cannot be operated unless all three windings are energized, and the armature cannot be retracted after operation until-the circuit of the winding 153 is broken. Controlling switches. The step-by-step motors 1. Fig. 1, at the transmitting and receiving stations are controlled from the stations P1, P2 by a relay 2, a change-over switch S being provided. The switch 3 controlling the relay 2 is operated through a differential gear D from the shaft 4 of the motor and a manually operated index-arm 8. In the arrangement shown in Fig. 17, a disk 89 manually operated through a shaft 88 is provided with a recess adapted to receive a pin 90 mounted on a lever 91. The lever 91 is mounted on a pin 92 and is provided with a projection 94 placed between the arms of a spring 95 mounted on the boss of the lever 91. The arms of the spring 95 embrace an insulated pin 96 mounted on a lever pivoted on the terminal 100 and carrying contacts 97, 98 adapted to engage contacts 101, 102 respectively. The pin 92 and contacts 100, 101, 102 are mounted on a base 93 adapted to be rotated by the transmitter motor 1, Fig. 1. The resistances 79, 80. Fig. 15, are connected between the contacts 100, 101 and 100, 102 respectively and according to the direction of rotation of the disk 89 one of these pairs of contacts are connected to short-circuit one of the resistances and this short-circuit exists until the base 93 has been rotated by the transmitter motor to cause the pin 90 to engage the recess in the disk 89. The base 93 may be fixed and the disk 89 operated by one element of a differential gear. When the angular motion of the shaft may be more than 360 degrees, two disks 89, 103, Figs. 18, 19, with recesses are provided. The disk 89 is secured to the shaft 83 and the disk 103 is operated from the shaft 88 through gearing 104, 105, 106 and 107. A pin on the lever 91 normally engages the recesses on the disks 89, 103, but after one revolution of the shaft 88 the pin is out of engagement with both recesses. Additional contacts 114, 117, Fig. 20, may be operated by the lever 91 through sectors 108, 109, these contacts being in the circuit of an auxiliary motor or in the fire control circuit of a gun. Transmitter and receivers, setting in phase and stopping in extreme positions. A shaft 124, Figs. 24 and 25, is geared to the shaft 4, Fig. 1, of each of the motors 1 and is keved to two disks 125, 126 which are geared to two similar disks 127, 128 by gearing 129, 130, 131, and 132. The disks 127, 128 are loose upon the shaft 124. The disks 126, 128 are provided with recesses adapted to be engaged by a roller 134, and the disks 125, 127 are provided with similar recesses adapted to be engaged by a roller 133. The roller 134 is mounted upon a spring 136 carrying a contact 138, and the roller 133 is mounted upon a spring 135 carrying a contact 137. The recesses in the disks 125, 126, 127, and 128 and the gearing between the respective pairs of disks are such that in one extreme position of the shaft 4 the roller 133 enters the recesses in the disks 125, 127 to separate the contacts 137, 139 in the circuit of the motor w