Sequential delivery valve apparatus and methods

A sequential delivery valve apparatus for sequentially delivering a gas propellant and a liquid product to a dispensing head from a container for ejecting an atomized spray of the liquid product from the dispensing head, comprising:

• a primary housing defining a primary chamber, the primary housing including a primary housing end wall and a primary housing exit, the primary housing also including a gas port configured for introduction of the gas propellant into the primary chamber from the container;
• a pusher disposed in the primary housing, the pusher being axially moveable relative to the primary housing, the pusher including a pusher bore, the pusher bore including a pusher port open to the secondary chamber;
• a primary seal disposed between the pusher and the primary housing end wall;
• a secondary housing defining a secondary chamber, the secondary housing positioned at least partially inside the primary chamber, the secondary housing being axially moveable relative to the primary housing and the pusher, the secondary housing also including a liquid port configured for introduction of the liquid product into the secondary chamber from the container;
• a secondary seal disposed between the pusher and the secondary chamber,
• wherein the pusher includes a first axial position wherein the primary seal engages both the pusher and the primary housing end wall, and wherein the secondary seal blocks the pusher port;
• wherein the pusher includes a second axial position wherein the primary seal is disengaged from the primary housing end wall, and wherein the secondary seal blocks the pusher port;
• and
• wherein the pusher includes a third axial position wherein the primary seal is disengaged from the primary housing end wall, and wherein the secondary seal is disengaged from the pusher port.