Drip emitter

Abstract

A drip emitter is provided for delivering irrigation water from a supply tube to an emitter outlet at a reduced and relatively constant flow rate. Water enters the emitter through a first inlet and proceeds into a first chamber. When the water pressure is above a predetermined level, a one-directional valve opens to allow fluid flow past the first chamber, through a tortuous path flow channel, and through an emitter outlet. A second inlet is used to compensate for water pressure fluctuations in the supply tube to maintain output flow at a relatively constant rate. Water enters the second inlet and presses a flexible diaphragm toward a water metering surface to provide pressure-dependent control of the output flow. A copper member is mounted to the emitter over the emitter outlet to prevent plant root intrusion into the emitter outlet.

What is claimed is: 
     
         1 . A drip emitter comprising:
 a housing defining an inlet and an outlet downstream of the inlet, the inlet receiving fluid at a first pressure and the outlet emitting fluid at a second pressure, the second pressure being less than the first pressure;   a flow path extending through the housing from the inlet to the outlet;   a tortuous path flow channel forming at least a portion of the flow path between the inlet and the outlet;   wherein the housing of the emitter includes a base and a raised rim extending from the base, the raised rim configured to be placed in sealing engagement with a wall of a supply tube to form an outlet path defined by a gap between the base of the emitter and the wall of the supply tube; and   a plate with a copper outer surface portion and being at the housing within the outlet path;   wherein the housing includes a peg being fixed relative to the base and extending outwardly therefrom and the plate defines a first hole for receiving the peg in mounting the plate to the housing.   
     
     
         2 . The drip emitter of  claim 1  further comprising a valve spaced from the inlet and having a diaphragm portion in sealing engagement with the housing to block fluid flow when the valve is closed and disengaged from the housing to allow fluid flow to the tortuous path flow channel when the valve is open. 
     
     
         3 . The drip emitter of  claim 2  wherein the housing further comprises an alignment member for engagement with the diaphragm portion to maintain a spatial relationship of the valve to the inlet. 
     
     
         4 . The drip emitter of  claim 3  wherein the alignment member is configured to block fluid flow through an opening in the diaphragm portion when the valve is closed and to allow fluid flow through the opening when the valve is open. 
     
     
         5 . The drip emitter of  claim 1  wherein the housing further comprises a first housing portion having a first attachment member and a second housing portion having a corresponding second attachment member, the first and second attachment members engaging one another for alignment and mounting of the first housing portion to the second housing portion. 
     
     
         6 . The emitter of  claim 1  wherein the plate is heat staked to the housing. 
     
     
         7 . The emitter of  claim 1  wherein the plate defines a second hole extending over the outlet. 
     
     
         8 . The emitter of  claim 1  wherein the plate defines an array of holes forming a screen. 
     
     
         9 . The emitter of  claim 1  wherein the plate having a base portion defining a second hole extending therethrough and mounted to the housing over the outlet and a folded portion extending over the outlet, the base portion and the folded portion defining a gap allowing the fluid flow from the outlet therethrough. 
     
     
         10 . The emitter of  claim 1  wherein the plate is comprised entirely of copper. 
     
     
         11 . The emitter of  claim 1  wherein the plate is comprised of a copper alloy containing 50% or more copper. 
     
     
         12 . The emitter of  claim 1  wherein the plate is comprised of a non-copper core surrounded at least in part by a copper layer. 
     
     
         13 . The drip emitter of  claim 1  wherein the plate is made from a non-fabric material. 
     
     
         14 . The drip emitter of  claim 1  wherein the plate is made primarily of metal construction. 
     
     
         15 . A drip emitter comprising:
 a housing defining an inlet and an outlet downstream of the inlet, the inlet receiving fluid at a first pressure and the outlet emitting fluid at a second pressure, the second pressure being less than the first pressure;   a flow path extending through the housing from the inlet to the outlet;   a tortuous path flow channel forming at least a portion of the flow path between the inlet and the outlet;   wherein the housing of the emitter includes a base and a raised rim extending from the base, the raised rim configured to be placed in sealing engagement with a wall of a supply tube to form an outlet path defined by a gap between the base of the emitter and the wall of the supply tube; and   an at least semi-rigid plate with a copper outer surface portion and being at the housing within the outlet path;   wherein the housing includes a peg extending outwardly therefrom and the plate defines a first hole for receiving the peg in mounting the plate to the housing.   
     
     
         16 . The drip emitter of  claim 15  wherein the peg protrudes from the base and into the outlet path.