US 2008/0289696 A1 · CHECK VALVE FOR FLUID INJECTOR

Abstract

A backflow-prevention system that substantially prevents contaminant backflow at a treatment site. The system includes a fluid ejector tube for insertion into the patient's mouth and for removal of fluids when a threshold vacuum pressure is applied. A backflow prevention device receives fluid from the fluid ejector tube and includes an internally positioned valve. The valve prevents contaminant backflow upon release of the vacuum pressure or a reduction in the vacuum pressure. Upon application of vacuum pressure, the valve moves into an open position to allow fluid flow away from the treatment site. The system can also include a disposable cover member that extends over at least portions of the fluid ejector tip, the backflow prevention device, and other features such as an ON/OFF valve assembly of a suction system. Similar principles of backflow prevention can be applied to fluid dispensers (e.g., liquid soap dispensers) wherein prevention of backflow of the fluid into the fluid storage container is necessary, in order for the dispenser to function properly.

Claims27

Dependent claims

A vacuum backflow prevention system, comprising:

a fluid ejector tube adapted for insertion into a patient's mouth;
a backflow prevention device, comprising:
a distal portion defining a valve seat portion and an inlet, the distal portion operable connected to the fluid ejector tube;
a proximal portion defining an outlet, the proximal portion configured for operative connection to a vacuum source and to the distal portion;
a valve member captured between the proximal and distal portions, the valve member moveable from a first position substantially blocking fluid flow between the inlet and the outlet, and a second position wherein a portion of the valve member is moved in a direction toward the outlet to permit fluid to flow from the inlet to the outlet under a vacuum condition applied by the vacuum source at the outlet;
and
a valve protrusion configured to bias the valve member into the first position.

4 more elements

Dependencies are inferred from the claim text.

Check valve for fluid injector

Life of this patent

Check valve for fluid injector

Life of this patent

Abstract

Claims27