上游文通大学 2.1 Functional Elements of an Instrument SHANGHAI JIAO TONG UNIVERSITY Bourdon tube, Bourdon tube data conversion Fig.2.3 Pressure Thermometer Linkage gearing, data manipulation Measured mediur Bulb,sensing variable conversion Pointer scale, Tube,data transmission data presentation 上游充通大学 SHANGHAI JIAO TONG UNIVERSITY 2.1 Functional Elements of an Instrument Ac power Variable conversion: line electrical pulses(电脉冲)to mechanical reciprocation(机械往复运动) Sensing arm Solenoid Micro- switch 003427 Switch. Rororing Variable conversion Mechanical shaft counter Fig.2.4 Digital Revolution Counter Counter: variable conversion Camlike(凸形)Projection+sensing arm, variable manipulation sensing variable conversion data presentation2.1 Functional Elements of an Instrument Fig. 2.3 Pressure Thermometer Measured medium Bulb, sensing + variable conversion Tube, data transmission Bourdon tube, data conversion Pointer + scale, data presentation Linkage & gearing, data manipulation 2.1 Functional Elements of an Instrument Fig. 2.4 Digital Revolution Counter Camlike (凸形) Projection + sensing arm, sensing + variable conversion Counter: variable conversion + variable manipulation + data presentation Variable conversion: electrical pulses (电脉冲) to mechanical reciprocation (机械往复运动) Switch, Variable conversion