Spray dispenser

A hand held spray dispenser comprising:

• a liquid chamber;
• an air chamber;
• and
• a mixing chamber;
• wherein flow of a liquid in the liquid chamber and flow of air in the air chamber towards the mixing chamber is prevented by one or more valves of the spray dispenser;
• wherein when the one or more valves are released, the liquid is forced under pressure from the liquid chamber to the mixing chamber via a liquid conduit and the air is forced under pressure from the air chamber to the mixing chamber via an air conduit to form an air-liquid mixture;
• wherein the air-liquid mixture in the mixing chamber is forced through an exit orifice of the spray dispenser as a spray, wherein the spray dispenser has a single collar sitting around the spray dispenser in a plane orthogonal to a long axis of the spray dispenser that is configured to be rotated about the long axis of the spray dispenser with a unidirectional twist to energise one or more springs in the spray dispenser;
• wherein energy from the one or more springs is released to generate sufficient air pressure and air flow and sufficient liquid flow for a spray to be formed from the air-liquid mixture as it leaves the exit orifice;
• wherein rotation of the collar forces a cam follower of the spray dispenser to progress about a helical cam ramp in the spray dispenser causing axial movement of an internal chassis in the spray dispenser;
• wherein axial movement of the internal chassis is configured to draw air into the air chamber and simultaneously energize a spring of the one of more springs to pressurise the air in the air chamber and the liquid in the liquid chamber;
• wherein the air from the air chamber is not used to pressurise the liquid;
• and
• wherein the air chamber comprises an inlet valve, wherein the inlet valve is configured to allow air to enter the air chamber whilst the air chamber is expanded.