Missing bearing detector

US4730484A · kind A · utility

Inventor

• Robert D. Olschefski · New Hudson, US

Key dates

• Filing date: Jun 20, 1986
• Grant date: Mar 15, 1988
• Expiry date: Jun 20, 2006

Classification

• Technology area (CPC G): Physics
• CPC primary: G01N29/14
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A missing bearing detector for an internal combustion engine in which the engine, at an early stage in the assembly process, is tested on the assembly line by rotating the crankshaft to move the piston assemblies through their reciprocal cycles; microphones are placed near the engine to pick up high intensity noises indicative of missing bearing parts; and encoder signals are generated for transmission to a comparator where they are compared to the noise signals generated by the microphones to indicate whether a bearing is missing and to indicate the particular piston assembly in which the bearing is missing. The detector also functions to distinguish between upper and lower bearing shell halves by noting whether relatively low level or relatively high level thresholds are violated by the fault signal and also distinguishes between pairs of piston assembiles moving in phased relationship by providing a pair of microphones axially spaced along the engine to thereby generate relatively high intensity and relatively low intensity fault signals depending upon the distance of the respective microphone from the faulty piston assembly.