INSTANTANEOUS SWEPT VOLUME MEASURING DEVICE FOR RECIPROCATING MACHINES

摘要

This invention relates to a device, which can be used for measurnii^ instantaneous swept volume of reciprocating machines. Svcp{ volume measurements are required for plotting PV diagram ! reciprocating machines, such as compressors, automotive engines The object of this invention is to make the measurcmeni ^w instantaneous swept volume simpler, easier and economical The devise consisting of a cam, which is fixed to the crankshaft o( flywheel, possesses a profile, which conforms to the relation between crank angle and swept volume, A dynamic non-contaci displacement sensor, having adequate frequency response t ^ measure the fast rotating cam profile is positioned to measure ihc profile geometry dynamically. The dynamic non- coniaci displacement-measuring sensor gives electrical output proportional to instantaneous swept volume of the reciprocating machine. The cam can be permanently fixed on reciprocating machines and ilie dynamic non-contact displacement sensor can be fixed whenever the measurements are to be performed, to enable the measuremenis to be performed on number of machines with single sensor lo i minimize the errors in measurement the measurement axis ot the dynamic non-contact sensor and the geometric center of the cam should coincide. Further the center of rotation of the cam and liie geometric reference center of the cam should coincide.