GB175311A - Improvements in or relating to means for detecting faults in or in connection with revolving shafts and other moving mechanical parts and/or the bearings or supports thereof - Google Patents

Abstract

175,311. Gardner, J. Aug. 11, 1920. Vibrations, indicating.-The condition of any of a number of shafts or other moving mechanical parts or bearings is ascertained at a central station by a common indicating-device by means of the amount and character of the noises generated in the bearings, or by visual indications caused by fluctuation of electric current in a normally-closed circuit originated by vibrations caused by breakage or other abnormal conditions or by variations of electric current caused by the altered electrical resistance of a member subjected to the rising temperature of a bearing in which lubrication is imperfect. The apparatus comprises microphones c<1> - - c<4> provided at the bearings b<1> - - b<4>, each microphone having one of its electrodes connected to its bearing. Leads d<1> - - d<4> connect one electrode to each microphone to a battery e connected through an ammeter h and a telephone j to the movable member of a switch f adapted to contact with any one of a series of contacts f<1> - - f<4> connected by leads h<1> - - h<4> to the other electrodes of the microphones. The ammeter h serves to indicate if the current is normal, so that the audible indications in the telephone may be relied on. But in the case of a microphone which has a contant resistance at a given temperature, the ammeter serves to indicate when a bearing becomes heated, due to the altered resistance of the microphone. Adjustable resistances j<1> - - j<4> or shunts may be connected in series with the microphones to secure uniformity under normal conditions. Two or more microphones may be employed at each bearing, having differing degrees of susceptibility or sensitive to disturbances of different characters, and these may be connected in series or parallel with a single switch contact, or each microphone may have its own contact.