Fluid transfer apparatus
A fluid transfer system includes a fluid container to receive a liquid and an apparatus for pressurizing liquid in the container including a deformable envelope defining a space for receiving a gas. Deformation of the envelope contracts the space to a contracted condition such that, when the space includes the gas, deformation of the envelope contracts the space to effect a transfer of a portion of the gas to the container to effect pressurization of the liquid in the container. A dispensing nozzle includes a fluid passage having a nozzle inlet and outlet, and an orifice defined by a valve seat. The nozzle inlet is in fluid communication with the container for effecting a discharge of the liquid from the container. A sealing member is biased into sealing engagement with the valve seat for sealing fluid communication between the nozzle inlet and the nozzle outlet.
1. A dispensing apparatus configurable in fluid communication with a supply container for dispensing a fluid therefrom, said dispensing apparatus comprising:
a. a fluid passage comprising:
i. an inlet;
ii. an outlet; and
iii. an orifice configurable to provide fluid communication between said inlet and said outlet;
b. a deformable envelope defining a space, configurable to receive said fluid from said supply container by action of a pressure differential between said supply container and said space, and operatively associated with said inlet for fluid flow thereto; and
c. a sealing member laterally separated from said deformable envelope, biased to a closed position that prevents a flow between said inlet and said outlet, and movable to allow said flow in an open position.
2. The dispensing apparatus of claim 1 , wherein movement of said sealing member and deformation of said envelope is achieved using an actuating means.
3. The dispensing apparatus of claim 2 , wherein said actuating means is configured to move said sealing member to said open position and to contract said space, in concert.
4. The dispensing apparatus of claim 1 , wherein said orifice is defined by a valve seat, and said sealing member is biased into a sealing engagement with said valve seat in said closed position.
5. The dispensing apparatus of claim 2 , wherein said pressure differential between said supply container and said space occurs by a reduction in pressure within said space relative to said supply container, created by a contraction and a subsequent expansion of said space using said actuating means.
6. The dispensing apparatus of claim 1 , wherein said envelope is resilient.
7. The dispensing apparatus of claim 1 , wherein said space is operatively coupled to said supply container by a flexible hose.
8. The dispensing apparatus of claim 1 , further comprising a first valve means configured to allow unidirectional flow from said space to said inlet.
9. The dispensing apparatus of claim 8 , further comprising a second valve means configured to allow unidirectional flow from said supply container to said space.
10. The dispensing apparatus of claim 9 , wherein each of said first valve means and said second valve means is a flapper valve.