Flow Sensor

Abstract

Flow sensors are provided that can provide both leak detection and flow monitoring. The flow monitoring enables a determination whether there are blockages or leaks in a fluid system during normal operation of the system. The leak detection enables detection of leaks when the system is shut off. The flow sensors can use a frusto-conical flow guide to provide a more compact flow sensor.

25 . A flow sensor comprising:
 an inlet;   an outlet;   a frusto-conical flow guide between the inlet and the outlet;   a surface moving in the frusto-conical flow guide based on an amount of fluid flowing through the flow sensor; and   an indicator representing the flow through the sensor in response to the movement of the surface.   
     
     
         26 . The flow sensor of  claim 25  further comprising a pivot interconnecting the surface and the indicator. 
     
     
         27 . The flow sensor of  claim 26  wherein the indicator includes an arm that moves along an arcuate path. 
     
     
         28 . The flow sensor of  claim 27  further comprising a float that indicates flow rate. 
     
     
         29 . The flow sensor of  claim 25  further comprising a piston and a shaft converting motion of the surface into rotational motion to operate the indicator. 
     
     
         30 . The flow sensor of  claim 29  wherein the indicator indicates an amount of flow through the flow sensor based on rotational movement of the shaft. 
     
     
         31 . The flow sensor of  claim 25  wherein the indicator includes an indicia indicating proper flow. 
     
     
         32 . The flow sensor of  claim 25  further comprising a spring biasing the surface upstream. 
     
     
         33 . The flow sensor of  claim 25  further comprising a straight flow guide upstream of and contiguous with the frusto-conical flow guide. 
     
     
         34 . The flow sensor of  claim 25  wherein the frusto-conical flow guide includes a longitudinal axis and includes at least one rib extending parallel to the longitudinal axis to guide linear displacement of the surface when moving in the frusto-conical flow guide. 
     
     
         35 . The flow sensor of  claim 25  wherein the indicator includes the frusto-conical flow guide being transparent at least in part to visually view movement of the surface. 
     
     
         36 . A flow sensor comprising:
 a first body defining an inlet and an outlet;   a flow guide associated with the first body;   a piston operating in the flow guide based on an amount of fluid flowing through the flow sensor;   a shaft converting linear motion of the piston to rotational motion of the shaft;   a second body that attaches to the first body and supports independently of the first body the piston and the shaft; and   a flow indicator cooperating with the shaft to indicate the flow through the flow sensor.   
     
     
         37 . The flow sensor of  claim 36  wherein the flow guide includes at least a frusto-conical portion and a straight portion upstream of and contiguous with the frusto-conical portion. 
     
     
         38 . The flow sensor of  claim 36  further comprising a cover portion associated with the second body. 
     
     
         39 . The flow sensor of  claim 36  further comprising a spring biasing the piston upstream in the flow guide. 
     
     
         40 . The flow sensor of  claim 38  wherein the cover houses the flow indicator. 
     
     
         41 . The flow sensor of  claim 36  wherein the flow indicator includes an indicator that points to indicia indicating the current amount of flow through the flow sensor based on rotational movement of the shaft. 
     
     
         42 . The flow sensor of  claim 36  wherein the cover is threaded onto the second body.