Automatic dosing and spraying valve assembly

A non-electrically powered automatic dosing and spraying apparatus comprising a valve assembly and a container of pressurised fluid with an outlet valve, wherein the valve assembly is connected to the container to open the outlet valve to permit the fluid to flow into the valve assembly and wherein the valve assembly comprises a housing containing at least two chambers wherein one of those chambers is a main chamber open at one end to the contents of the container and closed at one end by a movable plunger, and another of those chambers is a dose chamber closed at one end by the movable plunger and closed at the other end by a prodder seal formed between a movable prodder and a fluid outlet opening;

• wherein the movable plunger is biased against movement toward the dose chamber by a main spring means and a prodder spring means being connected to both the moveable plunger and the movable prodder;
• the assembly further comprises a fluid leak path between the main chamber and the dose chamber;
• and wherein the assembly is arranged such that, in use, the dose chamber with gradually fill with fluid and one movable component of the assembly is configured to move relative to another component of the assembly to provide a final and rapid expansion of the dose chamber, releasing and spraying a dose of fluid whilst substantially simultaneously therewith or substantially immediately thereafter returning to the start position to repeat the cycle.