Patent GB-105366-A (GB)
IPC: F17B1/00
Abstract: 105,366. Bourne, L. V. April 5, 1916. Tell-tale apparatus.-In a step-by-step indicator for liquid levels and gas-holders, the movement of the float or holder revolves a drum against the action of a weight, and the rope connecting the drum to the float or holder is coiled evenly upon the drum by means of a tranversely-moving guide-pulley mounted on a screw rotated by the movement of the drum. Two sets of circumferentially and radially adjustable arms are mounted on the drum shaft, one set operating a switch to send current impulses to the receiver when the drum revolves in one direction, and the other set operating a second switch to send current impulses to the receiver when the drum revolves in the opposite direction. To limit the length of the impulse when the float or holder is moving slowly, an electro-magnetically-operated switch is placed in the operating-circuit to break this circuit and partly close a restoring-circuit, which is com pletely closed, to reset the switch, by means of an auxiliary switch operated by one of the radial arms. The radial arms are spaced so that the interval between each impulse corresponds to a definite rise or fall of the float or holder, say six or twelve inches. The magnets of the receiver operate quadrants the pawls of which engage starwheels, the shaft of which is geared to the indicating-arms ; and each quadrant is provided with a device for lifting the pawl of the inoperative quadrant when the other is operative. The cubic contents of the vessel may be indicated by a graduated band operated by the indicator mechanism, and an audible signal may be provided for signalling the highest and lowest positions of the holder or float. Transmitter.-The transmitter comprises a drum 1, Figs 2 and 4, upon which a rope 2, attached to the float or holder, is evenly wound by means of a guide-pulley S mounted on a screwed spindle 10. The pulley 8 is mounted on a carrier 9, which is prevented from rotating with the spindle 10 by means of a grooved wheel 13 engaging two guide-bars 14. The spindle 10 is geared to the drum shaft 11 by a chain 12. The drum shaft 11 carries two sets of arms 18 screwed into collars 22, which are secured to the shaft 11 in an adjustable manner by means of set-screws. One set of arms is arranged to operate in succession two switch blades 19, 31 when the shaft 11 rotates in one direction, while the other set is adapted to operate two similar switches when the shaft operates in the opposite direction. In order that the switch blades 19, 31 shall be operated for one direction of rotation only of the shaft 11. a bell-crank lever 20 is pivoted on the blade 19 and a tappet 36 on the blade 31, so that the lever 20 and the tappet 36 turn inoperatively about their pivots when the arms 18 approach them in one direction. The contact blade 19 is adapted to close the circuit of the operating-magnet 51, Fig. 7, of the receiver, and the similar blade at the other end of the drum closes the circuit of the operating-magnet 51<a> of the receiver. To limit the length of the current impulse sent to the operating-magnet 51 when the float or holder is moving slowly, an electromagnetically-operated switch 27, 29, Fig. 6, is placed in the impulse circuit, this circuit also containing a magnet 25. When the current impulse passes through the receiver magnet 51, Fig. 7, and the magnet 25, the latter operates to open the impulse circuit at the switch 27, 29, and partially closes a restoring circuit at the contacts 28, 30, by the attraction of the armature 23 secured to a shaft 24 carrying the contacts 27, 28. A little later, an arm 18, Fig. 2, operates the switch blade 31 to close the restoring- circuit completely, thereby energizing the magnet 26 partly to close the operating circuit at the contacts 27, 29 and to open the restoring-circuit at the contacts 28, 30. When the shaft 11, Fig. 4, rotates in the opposite direction, the magnets 25<a>, 26<a>, 51<a> are similarly energized. Receiver.-The indicator arms 40, 41, 42, Fig. 5, are driven through gearing from the arbor 58, Figs. 7 and 8, of two star-wheels 57. 57<a>. The arbor 58 is operated in one direction by the operation of the magnet 51 upon a quadrant 54 provided with two pawls 55, 56 adapted to engage the starwheel 57; while the arbor is operated in the opposite direction by the operation of the magnet 51<a> upon a quadrant 54a provided with similar pawls 55<a>, 56<a> adapted to engage the star-wheel 57<a>. To disengage the pawl 55<a> from its star-wheel 57<a> when the quadrant 54 is operating the arbor 58. the armature 52<a>, carrying the quadrant 54<a>, is provided with an arm 63<a> carrying a member 61 engaging a member carried by the quadrant 54. The armature 52 of the magnet 51 is provided with a similar arm 63 adapted to lift the pawl 55 from its star-wheel 57 when the quadrant 54a is operating the arbor 58. To indicate the cubic contents of the vessel simultaneously with the height of the liquid or holder, a graduated band 66, Fig. 9, moved by the mechanism of the indicator, passes around a driven drum 68 and a drum 69 drawn down by springs 73 to keep the band 66 taut. To signal the highest and lowest positions of the float or holder, a bell 78, Fig. 5, is energized by the clcsure of its circuit at a switch 79, Fig. 9, operated by arms 81, 82 driven by the indicator mechanism. Two or more bells may be rung, and the bell 78 cut out by means of a switch 85, Fig. 5, to prevent continuous ringing. The Provisional Specification states that the rotary member carrying the radial arms may be driven by a rack and gears, and that the rotary member may be replaced by a rod or chain attached to the rising and falling body and having attached to it collars which operate switches. Reference has been directed by the Comptroller to Specifications 21496/97, 47159/98, 13722/00, 7732/05, [all in Class 106, Registering &c.], 23662/06, and 91/14.