Pump device for fluid dispenser

A pump device for use on a container device for dispensing fluid stored in said container device, said pump device comprising an actuating rod, a head element on the top end of said actuating rod, a fastening element, a piston element, a resilient element, a body member, and a fluid valve element, wherein

• said body member has a hollow chamber configured on top of an enclosure cap with a discharging spout extended from the outer wall of said chamber;
• said enclosure cap fastens said pump device to the opening of said container device;
• said chamber is partitioned into a pressure room and a fluid room;
• said pressure room is covered by said fastening element through which said actuating rod is extended;
• said piston element has a central through hole into which the other end of said actuating rod is embedded;
• said resilient element is housed inside said pressure room beneath said piston element;
• an air valve element is provided at the bottom of said through hole that is opened and closed automatically and synchronously with the up and down movement of said piston element;
• said air valve element is opened to allow air to flow into said pressure room via an air duct running from said head element to the bottom of said actuating rod and connecting to said through hole of said piston element;
• said air valve element is closed when air is driven out from said pressure room into said container device via an outlet hole;
• and
• said fluid valve element is fixedly positioned at the bottom of said body member, covering said fluid room from the bottom;
• said fluid valve element has a valve body and a valve lid;
• said valve lid is attached to said valve body which has a through hole in the center surrounded by an indented lid seat;
• said valve lid is flipped to fit inside said lid seat and seal said through hole of said fluid valve element;
• a positioning element provided inside said fluid room appropriately presses the folded section of said valve lid so that said valve lid normally closes said through hole of said fluid valve element.