Valve actuator

Abstract

Disclosed is an actuator for actuation of a fluid dispense valve in a pressurized fluid powered fluid dispensing device. The actuator comprising structure to generate a pressure differential between a first zone and a second zone. The zones being adjacent a valve member of the fluid dispense valve of the device such that upon generation of the pressure differential the valve member is moved from the zone of relatively higher pressure towards the zone of relatively lower pressure such that the valve is opened.

1 . An actuator for actuation of a fluid dispense valve in a pressurized fluid powered fluid dispensing device, the actuator comprising structure to generate a pressure differential between a first zone and a second zone, the zones being adjacent a valve member of the fluid dispense valve of the device such that upon generation of the pressure differential the valve member is moved by the pressurized fluid from the zone of relatively higher pressure of pressurized fluid towards the zone of relatively lower pressure of pressurized fluid such that the valve is opened. 
     
     
         2 . An actuator according to  claim 1 , the actuator comprising structure to generate a partial vacuum adjacent a valve member of the fluid dispense valve of the device such that upon generation of the partial vacuum the valve member is opened. 
     
     
         3 . An actuator according to  claim 2 , the partial vacuum creation structure comprising a pressure chamber adapted to be disposed in fluid communication with the valve member of the fluid dispense valve, the pressure chamber defining an internal volume, a pressurized fluid entry port to enable pressurization of the internal volume by pressurized fluid from a pressurized fluid source, the pressure chamber including a pressure release valve operable to enable release of pressurized fluid from the internal volume and an actuator body within the internal volume biased towards a first position and movable from the first position to a second position on operation of the pressure release valve to thereby generate in use, a partial vacuum chamber between the actuator body and the valve member to open the valve member. 
     
     
         4 . An actuator according to  claim 2 , further comprising the fluid dispense valve for use in a pressurized fluid powered fluid dispensing device, the actuator body defining an actuator body volume, the valve member of the fluid dispense valve being received in the actuator body volume in slidable relation thereto such that on movement of the actuator body from the first position to the second position, the partial vacuum chamber is generated in the actuator body volume. 
     
     
         5 . An actuator according to  claim 3 , comprising pressure equalization structure to cause closure of the valve member, the pressure equalization structure comprising a pressure equalization path into the partial vacuum chamber, the pressure equalization path being opened when the actuator body is in the second position. 
     
     
         6 . An actuator according to  claim 5 , the pressure equalization structure including a port defined by the actuator body, and structure to vary the rate of pressure equalization through the port. 
     
     
         7 . An actuator according to  claim 5 , the pressure equalization structure including a port defined by the actuator body and a port defined by the pressure chamber, the ports being disposed for fluid communication there between, the actuator body and or the pressure chamber being rotatable relative to one another to vary the extent of fluid communication through the ports. 
     
     
         8 . An actuator according to  claim 3 , the pressure release valve being operable both to enable release of pressurized fluid from the pressure chamber and to obturate the pressurized fluid entry port. 
     
     
         9 . An actuator according to  claim 4 , further comprising the outlet nozzle of the fluid dispensing device. 
     
     
         10 . An actuator according to  claim 3 , further including an actuator housing, the actuator housing defining a fluid flow path for flow of pressurized fluid within the fluid dispensing device, the pressure chamber being mounted internally within the actuator housing, the actuator housing defining the pressure release port in fluid communication with the pressure chamber, and upstream and downstream fluid dispense and entry ports. 
     
     
         11 . An actuator according to  claim 4 , wherein the pressurized fluid entry port of the pressure chamber and the pressure equalization path are both in fluid communication with the fluid flow path. 
     
     
         12 . An actuator according to  claim 3 , wherein the actuator is pressurizable from a pressurized fluid reservoir of the fluid dispensing device, a source of pressurized fluid that is located remotely from the device, or an onboard pressurized fluid cartridge. 
     
     
         13 .- 25 . (canceled) 
     
     
         26 . A method of operating a valve in a pressurized fluid powered fluid dispensing device, the method comprising the steps of providing a pressurized fluid source to the device, and thereby also pressurizing an actuator pressure chamber, initiating movement of an actuator body in the pressure chamber by releasing pressure through an orifice of the chamber, the actuator body being in fluid communication with a valve member of the valve such that by reducing pressure in the chamber a pressure drop is created in the chamber between the actuator and the valve member by the pressurized fluid sufficient to cause movement of the valve member against the force of a biasing device to thereby open the valve. 
     
     
         27 . A method according to  claim 26 , including the step of pressurizing the pressurized fluid powered fluid dispensing device by connecting the device to a source of pressurized fluid, such as mains water. 
     
     
         28 . A method according to  claim 26 , including the step of pressurizing a fluid containing reservoir of the device by connecting the device to a source of pressurized fluid, such as mains water. 
     
     
         29 . An actuator for actuation of a fluid dispense valve in a pressurized fluid powered fluid dispensing device, the actuator comprising,
 a housing structure, providing a fluid outlet, the housing structure supplied with fluid under pressure from a supply of pressurized fluid,   an obturator at least in part within the housing, which when in a first position seals off a dump chamber from external low pressure, the dump chamber supplied with fluid under pressure,   an actuator body at least in part within the housing, biased at least by the fluid under pressure in the dump chamber towards a first actuator body position,   a valve member at least in part within the housing, biased at least by the fluid under pressure in a volume defined between the actuator body and valve member, toward a first valve member position, which seals the fluid outlet,   on movement of the obturator to a second position fluid under pressure in the dump chamber is released to the low pressure, and supply of fluid under pressure to the dump chamber is also sealed off,   fluid under pressure acting on the actuator body moves it from the first actuator position to a second actuator position, and in doing so the volume is also closed off from the fluid under pressure, the valve member is then biased by a pressure differential between the lower pressure in the volume and the surrounding fluid under pressure, toward a second valve member position which unseals the fluid outlet,   at least one pressure equalization port is then opened to equalize the pressure differential when the actuator body reaches its second position, and the actuator body then moves back to its first position under action of a bias,   this in turn moves the valve member back to its first position sealing the fluid let.   
     
     
         30 . An actuator as claimed in  claim 29 , wherein movement of the valve member from its first to second position is caused by a low pressure in the volume, and fluid under pressure acting on a sealing face of the valve member to form the pressure differential. 
     
     
         31 . An actuator as claimed in  claim 29 , wherein movement of the obturator from the second position back to its first position is provided by a bias. 
     
     
         32 . An actuator as claimed in  claim 31 , wherein the bias may be mechanical such as a spring, or a formed by fluid pressure acting on a pressure surface. 
     
     
         33 . An actuator as claimed in  claim 29 . wherein the size of the equalization port may be adjusted to control the time take for the valve member to close after opening. 
     
     
         34 . An actuator as claimed in  claim 29 , wherein the valve member and actuator body are at least in part contained within and can slide along, and can seal to, an actuator cylinder, itself contained at least in part within the housing, the actuator cylinder containing one equalization port, the actuator body containing another of the actuation ports. 
     
     
         35 . An actuator as claimed in  claim 34 , wherein the actuator cylinder forms the dump chamber. 
     
     
         36 .- 39 . (canceled)