Patent GB-383615-A (GB)
Title: Improvements in or relating to indicating apparatus
IPC: G09B29/10
Filed: 1931-02-12
Abstract: 383,615. Control of motors ; electro magnetic, mercury and stencil switches. LAFFITTE, J., 24, Rue St.-Benoit, Paris. Feb. 12, 1931, No. 4495. Convention date, Feb. 12, 1930. Void [Published under Sect. 91 of the Acts]. [Classes 38 (iii) and 38 (v).] Ad apparatus indicating on a plad the location of a point it is desired to find comprises a transparent plan whereon the required point is indicated by an electric lamp which is displaced behind the plan according to two co-ordinates, which may be indicated on a band 59, Figs. 2 and 3, which is unrolled semi-automatically and carries an alphabetical list of.names of places shown on the plan. A cursor 8, Fig. 7, is adjusted relative to an adjacent alphabet to the first letter of the street &c. to be found and on depression of an external button 11 a circuit is completed through a solenoid 43 to the cursor 8 and the left-hand side of a bar 69, and thence to one of a pair of solenoids, each corresponding to one half of the bar 69. The particular solenoid actuated moves a sleeve 28 into engagement with one of two loose pinions 22, 23, driven in opposite directions from the motor 15 : the motor circuit is meanwhile completed by the armature 45 of the solenoid 43, and the motor rotates, moving the bar 69 until the insulating strip 74 comes below the cursor 8. This rotation 'brings the band 59 approximately to the point required. Each name on the list 59 is followed by co-ordinates for the corresponding point, these indications being inscribed along two slits 6, 7 on the table 1a, in which move cursors 9, 10 marking contact with bars 70, 71 similar to the bar 69. Depression of an external button completes two circuits through the electromagnet 43, and thence as in Fig. 7 through (i) the cursor 9, and the left-hand side of the bar 70 to one of a pair of solenoids; (ii) the cursor 10 .and the right-hand side of the bar 71 to one of another pair of solenoids. The solenoids serve in the same way as described in connection with the bar 69 to rotate the shafts 20, 21 in the appropriate direction. The shafts 20, 21 move the illuminated lamp to the desired point as determined by the cursors 9, 10 where it remains illuminated for a certain time. In addition special points of interest may be specified on the table 1a each having an appropriate button 14 which connects with suitable contacts beneath which the bars 70, 71 move as before until the insulating strips 74 break. the circuit. The light meanwhile is illuminated and has moved to the point required. The device may be modified in various ways. The cursors 9, 10 may be dispensed with, external buttons being provided for all the desired points. In place of the sleeve 28 the direction of rotation may be changed by reversing the direction of the current in the field coils .by the mechanism shown in Fig. 12. Depression of the button 13 closes circuit from the electro-magnet 43 through the conductor 103 and the cursor 10, to the bar,71 and thence to one of the coils 155, 156 of an electromagnet. Coil 156 is actuated to attract its armature 157, and the motor revolves until the strip 74 reaches the cursor 10. In a further modification, the band 59 comprises a list of names situated on strips, each comprising a black and a white part ; the point of separation between the black and white is the reference mark to which the cursors 9, 10 must be adjusted. By making, the white parts of the band transparent, the cursors 9, 10 may be dispensed with and photo-electric controls substituted therefor. The motor drives a shaft on which is mounted the selenium 'cell until it takes up this position relative to the band when the motor stops. At the same time the illuminated lamp 92 is moved to the required point. Again, the band 59 may be perforated at certain points on each line bearing a street name and contact is made through such perforations by projections on flexible laminations arranged above, one lamination being provided for each longitudinal line of perforations. The projections make contact with members arranged above the bars 70, 71 so. that these may be driven as before until the insulating strip 74 comes into contact with the connecting member. The contact is made by depressing an external button which presses the lamination upon the perforated band, so that the particular projection above any perforation may engage the connecting member beneath. Should the perforation be slightly out of place the band is automatically adjusted by a tooth on the depressed button which engages with a cog wheel on the shaft carrying the band. The cursor 8 may be replaced by a series of buttons arranged adjacent an alphabet, and the button corresponding to the initial letter of the street required is then depressed to actuate the band 59. To prevent depression of more than one button at a time the buttons 183, Fig. 24, are formed with notches 186, 187 and an inclined portion 188. When the button is pressed down, the finger 190 makes contact with a piece 191 which touches the member 69, and displaces a member 193 against the action of a spring 194. The member 193 engages the notch 186 of the depressed button and the notch 187 of the other buttons. In an alternative construction the interlocking member consists of a spring-held oscillating bar. The device may be further modified so that the external button actuating the lamp 92 need be depressed for an instant only. A switch is employed consisting of an insulating plate 198, Fig. 27, oscillatably mounted on a point 197 and carrying cores 199 of solenoids 200, one coil corresponding to each of the external buttons 14 to be actuated. The coils are mounted equidistantly round the plate and a weight is provided to maintain equilibrium. A mercury globule 211, when the plate is horizontal, is situated at the centre of the plate and covers contacts 203 connected to each of the solenoids 200 and the contact 202 of the centre post. The core 199 when attracted tilts the plate 203 and the mercury globule flows to the side to bridge four contacts 204 .. 207 situated thereon.