Hypodermic syringes
OwnerJeremy Francis Donnan, John Targellinventors
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Abstract
The barrel of a hypodermic syringe is provided with a restrictor in the vicinity of its open end, the restrictor having being designed so as ordinarily to retain liquid within the barrel prior to fitting of a needle unit to the barrel but being adapted to allow passage of a needle and needle mounting hub therethrough.
Claims45
A hypodermic syringe comprising:
- a barrel having an open end and provided with a restrictor in the vicinity of said open end,
- a plunger slidable in the barrel for drawing liquid into and discharging liquid from the barrel through said open end, and
- an injection needle unit for connection to the barrel, the restrictor having at least one aperture sufficiently small as ordinarily to prevent egress of liquid filling the barrel prior to connection of the injection needle unit to the barrel.
A hypodermic syringe having a barrel for use with a retractable needle assembly comprising a needle and a mounting hub for the needle, the barrel being provided with a restrictor in the vicinity of an open end of the barrel, the restrictor having at least one aperture which is sufficiently small as ordinarily to retain liquid within the barrel and being adapted to allow passage of the needle and mounting hub into the barrel.
A barrel for use with a retractable needle assembly comprising a needle and a mounting hub for the needle, the barrel being provided with a restrictor located internally of the barrel at or adjacent an open end of the barrel, the restrictor having at least one aperture which is sufficiently small as ordinarily to retain liquid within the barrel and being adapted to allow passage of the needle and mounting hub into the barrel.
Dependencies are inferred from the claim text.