Tubular metering or dosing mechanism for dispensing liquid from a container in successive quantums of uniform volume

Claim 1

For mounting in the dispenser neck of an invertable container for liquid for dispensing liquid from the container in successive quantums of substantially uniform volume upon successive inversions of the container, a tubular dosing mechanism, comprising: external wall means having outer peripheral surface means constructed and arranged to circumferentially sealingly engage the dispenser neck when the tubular dosing mechanism is introduced into the dispenser neck; first wall means defining a discharge channel having an axial extent, being outwardly open, relative to the dispenser neck into which the tubular dosing mechanism is to be introduced, and having an opposite, inner end closed by base wall means; second wall means defining a dosing channel extending axially internally of said first wall means and including means closing the outer end thereof relative to the dispenser neck into which the tubular dosing mechanism is to be introduced; said second wall means providing a partition between said discharge channel and said dosing channel, said partition terminating axially outwardly of said base wall means, so that between said base wall means of the discharge channel-defining first wall means and where said partition terminates a collecting region is provided, said collecting region connecting with both the dosing channel and the discharge channel, and having a volume at least as large as said uniform volume; means defining a liquid inlet opening into said tubular dosing mechanism and means defining a liquid outlet opening from said tubular dosing mechanism, both said openings being communicated to externally of the tubular dosing mechanism for communication internally of the container for liquid when the tubular dosing mechanism is introduced and sealed in the dispenser neck of such container; the axial spacing between said inlet and outlet openings being such as to cause there to be admitted from the container to the tubular dosing mechanism upon inversion of the container when the tubular dosing mechanism is introduced and sealed in the dispenser neck of such container an amount of liquid corresponding to said uniform volume; the axial spacing between said outlet opening and where said partition terminates providing a storage region having a volume that is as large as half that of the maximum free liquid which occurs upon an inversion of the container when the tubular dosing mechanism is introduced and sealed in the dispenser neck of such container; said outlet opening being located axially inwardly of said inlet opening; wall means defining an axially extending tubular channel opening externally through said base wall means at an inner end and having said outlet opening defined at an outer end thereof, said outlet opening being located within said dosing channel; and an orifice plate mounted in place covering said inner end of said tubular channel, said orifice plate having an orifice having a diameter which is one-half to one-fifth the diameter of said inner end of said tubular channel axially outwardly adjacent to said orifice plate.