Positive displacement dispenser

Claim 1

A dispenser for dispensing liquids such as correction liquids and the like comprising in combination: a. a housing having first and second chambers, said housing tapering at one end and forming a dispensing aperture for dispensing liquid from said second chamber; b. a cylindrical resilient bladder in said first chamber and defining a first liquid storage volume; c. a valve stem extending axially through said first storage volume; d. a conical valve seat surface formed in said housing between said first storage volume and said second chamber, e. an intermediate valve member formed on one end of said stem, said valve member having a frustoconical contact surface, f. means resiliently contacting said valve stem to urge said contact surface and said valve member in a direction to contact said valve seat in surface contact whereby flow between said first storage volume and said second chamber is prevented; g. an annular valve seat formed around the interior of said dispensing aperture; h. a ball valve normally contacting said annular valve seat to prevent flow of liquid from said second chamber; i. socket means contacting said ball valve; j. resilient means contacting said socket means to resiliently urge said socket means and said ball valve to move in a direction to seat said ball valve with said annular seat; k. radially movable actuator tabs extending from the exterior of said housing to contact said bladder for deflecting said bladder; and l. cam means extending between and contacting the interior of said bladder and said valve stem for simultaneously moving said valve stem in a direction to open said intermediate valve when said bladder is deflected whereby fluid is caused to flow from said first chamber to said second chamber.