Patent GB-191416997-A (GB)
Title: Improvements in Visual Signalling Apparatus particularly for use in Mines.
Inventor: RICHARDSON JOSEPH
IPC: B66B19/06
Filed: 1914-09-17
Granted: 1915-05-06
Abstract: 16,997. Richardson, J. Sept. 17. Mechanical telegraphs; bell and gong signals; lamp signals. - A visual signalling-apparatus for use in connexion with the usual audible signalling- apparatus for mines &c. is arranged so that a numbered lamp is lighted corresponding with the number of times the " rapper " rope is pulled, and is automatically darkened whenever a new signal is given, the last signal remaining visible until automatically cut out by the winding-mechanism ; provision is also made whereby a selected signal of a given number is illuminated and remains visible while signals of a lesser number are given, but this is also automatically cut out by the winding-gear. The apparatus comprises a cataract-controlled ratchet slide 1, Fig. 2, which is adapted to be raised by a pawl 14 operated by toothed segments 15 and a link 16 from the rapper rope, and an upper ratchet slide 20, which is adapted to be raised by the lower slide and then to be locked by a detent 24, Fig. 4, mounted on the axle of a spring- controlled trip-lever 27 located so as to be released by the winding-gear. The slide 20 carries a brush block having contact springs 33, Fig. 3, which are adapted to engage in turn with contacts 42 of a series of lamp terminals A, B, C, D, &c. When the rapper rope is pulled, the lamps are lit and extinguished successively until the lamp corresponding to the number of pulls is reached, and this remains visible until the mechanism is restored by the winding-gear. A retaining-pawl 17, Fig. 2, is provided to support the slide 1 during part of the return stroke of its lifting-pawl 14, but is released by an arm 19 when the pawl is in a position to engage another tooth. As the slide 1 is raised, it carries with it a headed rod 6, which, when the slide 1 falls, is retained in its upper position by a spring 8, allowing a bolt 4, Fig. 1, to be moved by a counterweighted pawl 5 into a position beneath a rod 29. If the rapper cord is pulled again before the winding-gear starts, the bolt 4 &c. lifts the rod 29, which engages the triplever 27, Fig. 4, and releases the detent 24 from the upper slide 20 ; this slide therefore falls on to the top of the slide 1, and depresses the rod 6 so that its lower end returns the bolt 4 to its original position. As the parts are so arranged, however, that the upper slide is not released until the lower slide is near the end of its upward stroke, it is impossible to extinguish the first lamp from the rapper cord. The means whereby a selected lamp remains visible while signals of a lesser number are given consists in the provision of a blade 37, Figs. 3 and 4, carried by a vertical slide 36 and adapted to wedge between springs 38, 39 connected respectively to the selected lamp, say No. 3, and the main terminal 40. The slide 36 is supported by a plate 31 slidable horizontally on the brush block. When signal " 3 " is given, the upper slide 20 is raised until the blade 37 wedges between the springs 38, 39, and remains in this position when the upper slide falls as a fresh signal, for instance No. 1, is given, so that lamps 3 and 1 are visible at the same time. To prevent No. 3 lamp from being lit when the brush block falls after a signal higher than No. 3 has been given, a cam - plate 45 is provided to engage the plate 34 and to move it horizontally ; a lower cam-plate 46 restores the plate 34 to normal position after the blade 37 has cleared the springs 38, 39.