Triple seal valve member for an atomizing pump dispenser

In an atomizing dispensing pump comprising:

• (a) means defining a pump chamber of substantially fixed volume having an inlet, said pump chamber having an opening at the inner end thereof;
• (b) valving means disposed at said inlet for preventing a back flow from said pump chamber;
• (c) a pump stem having a piston on the end thereof disposed for reciprocal motion in said pump chamber;
• (d) said pump stem having a passageway therethrough with a dispensing outlet at the outer end of said passageway and an axial inlet port located inwardly thereof;
• (e) a rigid valve member having an outer end portion cooperating with said axial inlet port to close off said port and an inner portion of a predetermined cross-sectional sealing area and of a length corresponding to the range of movement of said piston;
• (f) an annular member forming a throat disposed at said opening at the inner end of said chamber, said inner portion of said valve member cooperating with said annular member to form means sealing the inner end of said pump chamber with a surface to surface seal at said throat, as said pump is operated by depressing said pump stem, to prevent any flow from said pump chamber through said throat when said pump is dispensing;
• (g) detents formed on the inside of said pump body to retain said annular member in place.
• (h) means for supplying liquid in a container to said valving means;
• (i) means biasing said valve member outwardly so that the first end portion thereof closes off said inlet port, and thereby also biasing said pump stem outwardly;
• (j) the cross-sectional area closed off at said inlet port being smaller than the cross-sectional area of said second end portion of said valve member at the point where it is sealingly guided,
• (k) said rigid valve member being;
• (l) an integrally molded plastic having:
• (i) said outer part terminating in a sealing tip for sealing against said inlet port, said outer part being of a first cross section;
• (ii) said inner part containing therein a hollow recess open at its inner end for accepting said means biasing, said inner part being of a larger cross section than said outer part, the radially outer portion of said inner part adapted to seal against said annular member;
• (iii) an intermediate portion forming a generally cylindrical recess between said inner and outer parts, said recess in communication with said hollow recess in said inner portion;
• (iv) a narrowed throat formed at the area of communication between said hollow recess and said cylindrical recess;
• (v) said intermediate portion having openings therein in the vicinity of its outer end permitting communication between said cylindrical recess and the area above said inner portion;
• and
• (vi) a ball having a diameter which is less than the diameter of said cylindrical recess but greater than the diameter of said throat snapped into said cylindrical recess to thereby form therewith a check valve, said valve member thereby forming the valving means at the inlet to said pump chamber.