Syringes and methods of syringe manufacturing
AssigneeNordson Corporation
InventorsHenry DiGregorio, John Higson, Jefferey White
Life of this patent
Estimating the term…
Abstract
A syringe for holding fluids susceptible to void formation when frozen and thawed before use. The interior surface of the syringe sidewall may be roughened, which serves to prevent or significantly reduce the incidence of void formation in the fluid. The required level of surface roughening for counteracting void formation may be reduced by increasing the sidewall flexibility. Alternatively, the flexibility of the syringe sidewall may operate over certain thickness ranges to prevent or significantly reduce void formation in the fluid without intentionally roughening the interior surface.
Claims19
A syringe for use with a fluid, the syringe comprising:
- a barrel including a first opening, a second opening from which the fluid is dispensed, a sidewall between said first and second openings, an inwardly-facing surface on said sidewall, and a plurality of axial grooves defined in said inwardly-facing surface, said inwardly-facing surface and said axial grooves configured to be contacted by the fluid, said inwardly-facing surface centered about a longitudinal axis extending from said first opening to said second opening, and said axial grooves extending along said inwardly-facing surface substantially parallel to said longitudinal axis from a first location on said inwardly-facing surface proximate to said first opening to a second location on said inwardly-facing surface proximate to said second opening;
- and
- a piston disposed inside said sidewall of said barrel to define a fluid chamber between said piston and said second opening that is in fluid communication with said second opening, said piston having a periphery that provides a fluid seal with said axial grooves to inhibit fluid leakage from said fluid chamber between said piston and said inwardly-facing surface as said piston is advanced toward said second opening to dispense the fluid from said fluid chamber through said second opening.
Dependencies are inferred from the claim text.