GB191421637A - Improvements in and relating to Signalling Appliances for Collieries and the like. - Google Patents

Abstract

21,637. Robertson, R., Bowman, J., and Ringrose, F. Oct. 28. [Cognate Application, 24,583/14.] Bell signals; mechanical telegraphs.-A signalling-appliance for collieries &c. comprises a dial and a pointer connected to a ratchet-wheel 3, which is operated by a spring-pressed pawl on a sliding-rod 1 actuated by a connecting-rope &c. The pawl 7 is prevented from backward motion by a fixed pawl 26 on a lever 24, which can be moved out of engagement with the wheel 3 by an arm 35 on a lever 23, which at its inner end has an inclined face 34 for simultaneously withdrawing the pawl 7 from the wheel 3. The pawl 26 may also be withdrawn from the ratchet-wheel by the falling, under oil or like friction, of a weighted cylinder 14 which has been drawn up by the movement of the rod 1 and then released. The tooth 26 is held away from the wheel 3 by a notch 30 in a pendent lever 31 engaging a pin 29 in the lever 24. The lever 23 is actuated to release the wheel 3, when the engine starts, by a rod 36, Fig. 5, connected by a bellcrank 37, 38 to an horizontal sliding member 39, 41, which is moved by a carriage 42 bearing brake blocks 46 pressed against a disk 44 when the carriage 42 is raised by a ball governor acting through levers 61, 62. Motion of the carriage in either direction moves the member 39, 41 to the left. Means is provided whereby the pawl 7 may not be withdrawn from the wheel 3 when the engine starts. In a modified form of cancelling- mechanism, Fig. 8, a floating lever 74 is raised by a pull on the rope to bring and hold a disk 76 against an engine-driven disk 44. When the lever 74 is allowed to fall, the disks 44, 76 are disengaged and the indicator put back to zero.