Patent Application
20070007369
The present invention relates to a mister nozzle and especially to a mister nozzle having a check valve incorporated therein to shut off the water passing through the misting nozzle to prevent draining of the water from the mister water supply pipes.
In a typical nursery propagation house, mist nozzles are suspended above the plants on polymer tubing. Water is supplied to these nozzles through polymer tubes from an overhead system of pipes and valves. A valve must be positioned between each mister and the polymer tubing which is shut off to prevent the whole system from draining out through the nozzles when the water is turned off. When the water supply is turned on, pressure builds to a point overriding a check valve so that the valve opens. When the water supply is turned off, the pressure in the system drops so that the check valve is closed to prevent the water from draining out the mister nozzles. When the system pressure drops to a point equal to or less than the check valve seal force, the valve shuts and traps the remaining water in the system. Prior check valves have been separate products consisting of several parts. A check valve is vented through small vent holes that connect the vented side of the check valve seal to atmosphere through the side of the valve. The mister is a separate component having several parts which is attached to the bottom of a check or other valve hanging on the end of each polymer tube in the nursery propagation house.
Prior U.S. patents that involve water misting may be seen in the Corrigan U.S. Pat. No. 4,882,189 for a method of spraying water mist onto produce in a display case. Water is delivered to the nozzles by an upwardly extending supply pipe within the case, eliminating the need for an overhead mounting structure. The Hayman, Jr. et al. U.S. Pat. No. 4,914,339 is a misting system constructed of plastic pipe which is drilled and threaded to receive nozzle assemblies. Each nozzle has a valve that does not bleed to atmosphere so it requires another valve to lower the system pressure after the water supply is turned off. The Marcus U.S. Pat. No. 5,330,104 is a portable outdoor mister for providing a comfortable region within a relatively hot, dry environment and has a reservoir of water and a pump to supply the water for the spray. The Wintering et al. U.S. Pat. No. 5,441,202 is a misting system with improved couplers. This system has an automatic drain valve which includes a check valve operating in the reverse direction and can be positioned anywhere in the system by replacing a nozzle with the drain. The Jones U.S. Pat. No. 6,651,901 is a misting system nozzle holder with a manual slide shutoff valve. The misting system valve assembly is connected to a pressurized fluid supply.
The present invention advantageously combines a nursery mister with a check valve, eliminating a number of the components of a separate check valve and mister nozzle and, advantageously, vents the mister check valve to atmosphere downstream of the flow metering port and through the nozzle itself, allowing the incorporation of the check valve and a mister into one compact unit with the check valve located inside the mist nozzle housing downstream of the inlet port and upstream of the nozzle outlet.
A mister nozzle apparatus has a misting nozzle housing having a water inlet and an outlet therefrom. A swirl chamber in the housing is adjacent the outlet for creating a mist in the outlet. A check valve is located in the housing and has a seal support supporting a valve element, which may be a resilient membrane. The valve element has a closed position blocking the passage of water through the inlet until water in the inlet reaches a predetermined pressure and an open position which opens by moving the resilient membrane to open the passageway through the inlet into the swirl chamber upon water entering the inlet exceeding a predetermined pressure so-that the mister nozzle shuts off the water passing therethrough to prevent draining of water from the water supply. The check valve is vented to atmosphere through a vent located in the housing between the resilient membrane and the swirl chamber. The inlet may have a raised lip to act as a valve seat for the resilient membrane. The resilient water sealing membrane is mounted in the housing and is compressed between a seal support on one side and the water inlet port on the other side. The resilient seal pressing against the inlet port opening prevents the system from draining out through the nozzle. The check valve is vented to atmosphere downstream of the flow metering port and through the nozzle itself which allows the incorporation of the check valve and the mister nozzle into one compact unit centrally located inside the mister nozzle housing and downstream of the inlet port and upstream of the nozzle outlet. This allows for a more compact mister and check valve.
Other objects, features, and advantages of the present invention will be apparent from the written description and the drawings in which:
Referring to the drawings of
The valve or seal support 21 with the resilient membrane seal 23 attached is pushed against a valve seat 26 which is a lip formed on the lower end of the inlet 12. In this manner, the inlet 12 is sealed by the sealing membrane 23 to prevent water in the inlet 12 from passing through the misting nozzle, as shown in
An important feature of the misting nozzle 10 is the check valve 20 which is vented to atmosphere through the check valve vent 22 and is vented downstream through the swirl chamber 14 and nozzle outlet 13 and allows the incorporation of the check valve and the mister nozzle into one compact unit. The check valve is simply located inside the mist nozzle housing 11 downstream of the inlet port 12 and upstream of the nozzle outlet 13. The vent 22 is provided to connect the vented side of the check valve seal or valve element 23 to the low pressure area provided by the swirl chamber 14 and nozzle outlet 13. Venting of the check valve is done downstream of the flow metering ports 19. This downstream low pressure position allows the check valve to respond rapidly to changing system pressures.
As seen in
It should be clear at this time that a nursery mister and check valve has been provided which combines a mister nozzle with a check valve to form a more compact combined unit with fewer parts than used in conventional mister nozzles and check valves. However, the present invention is not to be construed as limited to the forms shown which are to be considered illustrative rather than restrictive.
