Trigger sprayer having a two-piece housing construction

In a trigger sprayer apparatus for dispensing liquid from a container connected to the apparatus, the apparatus having a sprayer housing and a nozzle for dispensing fluid, a trigger mounted for pivoting movement relative thereto, a pump chamber formed in the sprayer housing and a pump piston connected with the trigger and received in the pump chamber for reciprocating movement therein in response to pivoting movement of the trigger, the reciprocating movement of the pump piston alternately drawing fluid from the container into the pump chamber and forcing fluid out of the pump chamber and through the nozzle, an improvement comprising:

• a vent housing discrete from the sprayer housing, a vent chamber formed in the vent housing, the vent chamber having at least one sidewall surrounding an interior volume of the vent chamber and separating the vent chamber from the interior volume of the container, and a vent opening extending through the sidewall and communicating the interior volume of the container with the interior volume of the vent chamber, the vent housing being assembled to the sprayer housing;
• and,
• means associated with the trigger and the vent chamber, said means being responsive to pivoting movement of the trigger for alternately enabling communication and preventing communication of the interior volume of the container with an exterior environment of the container through the vent opening and the vent chamber.