Mechanism for feeding stick type cosmetic materials, container employing

Abstract

A mechanism for feeding a core material such as a stick type cosmetic material includes an internal thread member having a spirally grooved inner surface and a push rod provided with a group of protrusions which engage with the spiral groove of the internal thread member; wherein the push rod is advanced or retracted by turning the internal thread member and the push rod engaged therewith relative to each other to feed the core material housed in a container to be slidably moved the push rod. Since the protrusions on the surface of the push rod can be of a simple shape, the push rod can be produced easily, and this effect manifests particularly in a comparison with the case where a thread must be formed on the push rod over the entire length thereof, requiring laborious thread machining or die making. Depending on the grouping (selection) of the protrusions provided on the outer surface of the push rod so as to occupy partially at strategic positions an imaginary continuous spiral space, the pitch, lead and direction of torsion of the resulting 'screw' can arbitrarily be selected within a certain range. Further, since the push rod itself has a spiral function, the diameter of the push rod and that of the main body of the container can be reduced.