| 摘要 |
<p>A fluid flow meter is provided and comprises a housing having a fluid inlet and a fluid outlet and a fluid passage for connecting the inlet with the outlet. The fluid passage further includes an elongated cylindrical chamber having one end open to the inlet and the other end open to the outlet while a piston is axially slidably mounted within this housing chamber and movable between a first and second position. The outer periphery of the piston is sealed to the housing. The piston includes a removable orifice plate having a fluid port open to the inlet end of the chamber while a fluid passage formed through the piston fluidly connects the port with the outlet end of the chamber. The rod is positioned within the housing and held in place by removable housing and covers. The rod includes a tapered portion positioned through the port which variably restricts the port in dependence upon the axial position of the piston. A resilient member urges the piston towards the inlet end of the chamber while an indicator is connected to the piston to provide an exteriorly visible signal of the axial position of the piston member and thus of the flow through the flow meter. Further, the piston assembly is constructed as a cartridge assembly so that the top cover can be removed and a new cartridge assembly installed quickly and easily. A set point is provided so that the new cartridge can be quickly zeroed. t</p> |
