Abstract: An atomizer assembly comprises a nozzle mounted in a push-button mounted on a tubular extension to a first piston of the assembly. The first piston is slidable in a first cylinder or pump chamber and defines a seat of a valve. A valve member co-operating with the seat forms part of a second piston slidable in a second cylinder defined by the first piston. Depression of the push-button causes pressure in the pump chamber to increase and at a certain point the valve member is lifted from the seat so that liquid under pressure passes to the nozzle.

Abstract: An atomizer comprises a cylinder defining a pump chamber and containing a piston. The chamber communicates with an atomizer nozzle by a valve comprising a valve member which is opened at a predetermined liquid pressure during operation of the piston to pressurize the liquid in the pump chamber. Liquid is fed into the pump chamber through a conduit which projects upwardly into the cylinder. A sleeve rigid with the valve member or the piston engages the conduit during operation of the piston to prevent communication between the conduit and the pump chamber.

Abstract: A pump primarily intended for incorporation in a dip-tube sprayer includes a hollow piston slidable in a cylinder which communicates with an outlet tube. The piston defines a seat for a valve which in the inoperative condition prevents communication between the cylinder and the outlet or delivery tube. The piston has the form of a shallow cup and is not totally covered by the valve when seated. One or more bleeds are provided in the part of the piston covered by the valve.

Abstract: An atomiser having a tapered pump chamber in which a valved lipped piston is slidably mounted, the piston being compressed radially inwardly by the tapered pump chamber to ensure a tight seal between the valve and its valve seat.