Patent GB-133127-A (GB)
Title: Improvements in Means of Correlating a Desired Operation on a Travelling Carriage with its Position Along a Track.
Inventor: LLOYD GUY ERNEST
Filed: 1918-09-23
Abstract: 133,127. Lloyd, G. E. Sept. 23, 1918. Mechanical dispatch apparatus.-In apparatus for correlating a desired operation in a travelling carriage with its position along a track, of the kind described in Specifications 17344/08 and 15920/10, where a member is rapidly given a set- ting at one point on the track and subsequently moved into operative position step by step as pos- sible operative stations are passed, the member is acted on by a steady force tending to move it, and is controlled by an escapement or detent which engages teeth and is oscillated, when a set- ting has rapidly to be given, by an electro-magnet energized by alternating or intermittent current. The member to be set may be a rack or a toothed wheel, and the setting thereof may be in the same direction as, or the opposite direction to, the step-by-step motion of the member as it passes the various possible operative stations. The steady force tending to move the member prefer- ably acts continuously, and may be derived from a falling weight, a spring, fluid pressure, a mag- netic solenoid, the magnetic torque of a revolving armature, or some form of friction drive from the axle of the travelling carriage or other continu- ously rotating part. Generally, the operative position of tha device on the travelling carriage is one in which a switch closes an electric circuit. Various constructions embodying the invention are described, as follows :-(1) The switch is oper- ated by a sliding bar 1, Fig. 1, carrying rack teeth 2 engaged by an escapement 3, which is oscillated by an electro-magnet 5 attracting its armature 6 and by a spring 7. The bar 1 is con- stantly acted on by a spring 4, and at the end of its stroke closes a switch 8 in a circuit which causes the desired operation to be performed. At each point on the track the magnet 5 is energized once, so that bar 1 moves through the distance represented by one tooth. The magnet 5, in the preliminary setting of the apparatus, is energized a number of times equal to the total number of teeth in the bar 1 less the number of stations the carriage is required to pass before the switch 8 is closed to perform the desired operation. A mechanical device may be substituted for the magnet 5. (2) The switch may be closed when the bar 1 returns to its original position.. The spring 4 is replaced by a friction wheel 9, Fig. 2, bearing against the bar continuously or when the apparatus is to be set. The step-by-step back- ward motion of the bar is effected by a friction wheel 10 moved into contact with the bar after the setting. (3) The bar 1 engages a toothed pinion, which is also engaged by a toothed slide adapted to be moved by a star wheel operated by pins situated at the operative positions along the track. (4) The switch 8, Fig. 5, is closed when a conducting peg 8<a> comes between the brushes 8 bearing one on each side of an insulating annulus carried by a toothed disk 1 which replaces the bar 1 in the previously described arrange- ments. The steady force is applied by a friction band 15, which is driven from the travelling car- riage and which may be mounted on a pulley formed integrally with the toothed disk, or on a loose pulley which bears by spring pressure against a pulley mounted on the shaft of the toothed disk. The torque of the friction band may be replaced by that produced in an armature, attached to the disk, by a magnet rotated about the axis of the armatute. (5) The extended axle of the disk 1 carries paddles 26, Fig. 8, in a bath 27 of thick fluid which is rotated by a cord 27a from the car- riage axle, thus applying a steady torque to the disk. The escapement is attached to two arma- tures 6, magnetically insulated from each other, and maintained of opposite polarity by a magnet 28, Figs. 8 and 9. When the magnet 5 is ener- gized by alternating current, its poles alternately attract and repel the armatures 6 and so oscillate the escapement. (6) The part 1 is a differential centre keyed to a spindle 25, Fig. 13, and in gear with wheels 12, 13 mounted free on the spindle. Wheel 12 carries teeth 2 for the escape- ment and is subject to the torque of a friction band 15. Wheel 13 is driven by a star-wheel 14 actuated by pins on the track. For enabling an apparatus to transmit its setting to another ap- paratus in a passing carriage, brushes 31, Figs. 8, 12, and 13, rub on a conducting ring 32 in the disk 30, or on a separate disk 30<a>, the brushes being in circuit in series through both magnets 5 with a source of alternating or intermittent cur- rent. The circuit may, for example, be through wipers carried by the passing carriage. In the normal position of the receiving apparatus, which is shown uppermost in Fig. 12, the gap in the conductor 32 is bridged at 33 until the disk 30 begins to turn. The disks move together at each energization of the magnets 5 until the lower or transmitting mechanism is back to its normal position, when the setting of the receiving mech- anism will correspond with the original setting of the transmitting mechanism.