Engineers are quite interested in a device lately brought forward for sounding an alarm whenever a bearing gets hot, that is, an overheating bearing. The arrangement consists of a cup containing some mercury, this cup being set in the bearing, and wires are connected from the cup to a bell and annunciator, one of the wires leading from a screw that can be set at any desired distance from the surface of the mercury; this screw is screwed down until it touches the mercury, and the circuit completed through the mercury; causing the bell to ring, and the screw is then backed any distance required. Should the bearing become heated, the mercury expands, closing the circuit when it touches the screw, and thus giving the alarm.
It is proposed to have one on each bearing, the belief being expressed that, though this would lead to a multiplicity of numbers, and probably some confusion at times, no doubt can be entertained that it would save fires very often in such places saw-mills; also in some portions as of to to cotton mills, where dust is likely get into a bearing and cause it heat, this arrangement, it is thought, may serve a useful purpose.
The inventor recommends that the mercury cup configuration be implemented for each bearing the assembly. In that way, overheating bearings can be identified and the alarm raised before catastrophic failure occurs.