Patent GB-190322087-A (GB)
Title: An Apparatus for Establishing Electrical Correspondence Selectively.
Inventor: DESPRADELS LOUIS
Filed: 1903-10-13
Granted: 1904-02-25
Abstract: 22,087. Despradels, L. Oct. 13. Signalling-instruments.-Relates to electric selecting-systems in which one or more signals in the form of drop shutters or otherwise can be displayed at one station on a common party line, to the exclusion of other stations not called up. The signal device is described as applicable to railway signalling, in which case discs or other optical signals may be used. Fig. 10 shows diagrammatically two stations V, VII on the common line 85. The dial of each instrument is provided with as many pushes 11 as there are stations on the line, and as many pushes 11<a> as there are varieties of signal to be sent. The letters A, B, C, &c. indicate the various signals. The dial also bears a drop shutter 3 for each signal, and one drop shutter 3<a>, spaced differently at each station, which falls when that station is called. When this calling-shutter drops, the contact 82, 83 is closed, and a battery 86 rings the bell 87 and energizes the electromagnet 81. An operator wishing to send certain signals to one ormore stations on the line, depresses one or more of the calling-pushes 11 and also one or more of the signal-pushes 11<a> according to the orders or signals to be sent. The pushes 11, 11<a> are provided at the inner ends with heads 15, Fig. 2, beneath which engage spring bolts 18 when the pushes are depressed. The ends of the depressed pushes are in the path of a brush 22 carried by an arm 21 rigid with the shaft 10, and this brush makes one revolution when the signals selected by means of the pushes are despatched by the operator. The rotation of the shaft 10 and the despatch of the signals are effected in the following manner :-A clockwork mechanism 35 tends to drive the shaft 10 at a speed which is the same for all the stations on the line, but, in the normal or inactive position of the apparatus, a bolt 39 engages in an aperture in a disc 44 on the shaft 10, and an arm 45 projecting from the bolt prevents the movement of the balance 36. The shaft 10 carries a ratchet-wheel 57 and a loose ring 53, and its end projects through a fixed insulating-disc 49 bearing three metal segments 50, 51, 52. When the operator rocks the arm 60 to effect the despatch of the signals, the disc 53 is rocked through a sufficient angle to release a pawl from a detaining-block and to allow it to drop into contact with the ratchet-wheel 57. The arm 54, Figs. 2 and 10, which bears the pawl, also carries a brush 55 which makes contact normally with the segment 50. The first movement of the disc 53 and arm 54 causes the brush to make contact between the segments 50, 51. The battery 84 then energizes the electromagnet 31, Figs. 2 and 10, through the circuit 92, 93, and earth. At the same time, the brush 69 has been brought into contact with the metal ring 70, which is connected to the line-wire 85, and current from the battery 84 flows to line through the arm 54 and brush 69, and energizes the electromagnets 31 at all the stations. The circuits from line to earth through the electromagnets 31 at the various stations are completed through the wires 95, contacts 76, 72, arms 54, brushes 55 (which are stationary), contacts 50 and wires 93. The electromagnets 31 serve to rock the levers 27 and sleeves 24 at all the stations and draw forward the hooks 40 and rods 39, thus releasing all the clockwork mechanisms. The shafts 10 then proceed to make one revolution at uniform speed, and, as the pawl carried by the arm 54 at the transmitting-station has been engaged with the ratchet-wheel 57, the disc 53, arm 54, and brushes 55, 69 at that station make one revolution with the shaft, the discs and brushes at all the other stations remaining motionless. As soon as the brush 55 is clear of the segment 51, the current in the line ceases, but it is renewed when the brush 22 makes contact with the depressed push 11 (in this case the plug VII). The circuit of the battery 84 to line is then closed through the wire 90, push VII, brush 22, wire 91, segment 52, and brushes 55, 69. All the electromagnets 31 except that at the transmitting-station are then again energized, and at station VII the movements of the levers 27, 23 take place when the lever 23 is immediately opposite the tail 32 of the shutter-releasing lever 5, and the shutter 3 drops. At all the other stations, the movement of the lever 23 is idle. The bell 87 is thus rung, the electromagnet 81 energized, and the contact 88, 89 permanently closed until the shutter is lifted by hand after the signal has been received. After the brush 22 at the transmitting-station has made half its revolution, it comes into the field of the signal pushes. Whenever it passes a depressed push, the battery 84 is put to line, but, as the ring 72 on the shaft 10 has now turned so far as to bring the insulating-portion 71 beneath the contact 76, the circuit from line to earth through the electromagnets 31 is broken at all the stations except VII, where the circuit is closed through 95, 88, 89, 96, 93. Consequently, the signal shutters only fall at station VII, the call and the signals being confined to that station to the exclusion of the others. In a modified form, the electromagnet 31 rotates with the shaft 10 and acts directly on the lever 23. The drop shutter may also be released by the opening of spring claws formed at the end of a split tube and serving to grip a band on the inside of the shutter.