System and method for safety syringe

Inventors

Shanley, Conor Edward • Diaz, Stephen H. • Shluzas, Alan E. • Tillack, Jeff

Assignees

Credence Medsystems Inc

Abstract

A syringe assembly includes a syringe body, needle assembly, retaining clip, gasket, needle latch, and needle hub. The syringe body has a syringe interior, longitudinal axis, proximal and distal ends, and needle attachment interface disposed at the distal end thereof. The gasket is configured to be compressed to provide a liquid-tight seal around an outer diameter of the needle assembly and the distal end of the syringe body. The needle latch assembly includes first and second latching tabs configured to retain the needle assembly in a close state and to be plastically deformed to an open state to release the needle assembly, and a gasket backstop configured to provide a flat surface for compression of the gasket, where the first and second latching tabs are spaced apart from the gasket such that neither of the first and second latching tabs contact the gasket during compression of the gasket.

Core Innovation

The described invention relates to a retractable safety syringe assembly in which a needle assembly is retained in a close state and is then retracted into a syringe body after injection. The assembly includes a needle latch assembly with first and second latching tabs that retain the needle assembly in the close state and are configured to be plastically deformed to an open state to release the needle assembly. The latch release is coordinated with sealing components so the syringe is configured to prevent liquid from leaking to an exterior during injection while still enabling subsequent needle retraction.

A liquid-tight gasket seal is compressed around an outer diameter of the needle assembly and the distal end of the syringe body, and the needle hub has interior surfaces configured to retain the needle latch assembly, the gasket, the retaining clip, and the distal end of the syringe body in a sealed configuration. The needle latch assembly further includes a gasket backstop configured to provide a flat surface for compression of the gasket. The first and second latching tabs are spaced apart from the gasket such that neither of the first and second latching tabs contact the gasket during compression of the gasket, reducing interference between the latch release structure and the seal.

Various needle latch geometries are described to support the plastically deformable latching tab behavior and to coordinate with the gasket-based sealing arrangement. Examples include a flat disc-shaped needle latch with asymmetric deformable tabs and aligned openings of different sizes, three-dimensional disc-shaped needle latch assembly variants including joining members, and embodiments with an elastically deformable section. The described variants also emphasize configurations that reduce part count, including unitary stamping or cutting from sheet metal to form cage and latch features, thereby improving manufacturability and consistent unlatching while minimizing interference with the gasket.

Claims Coverage

The partial content contains one independent claim (clm-00001). The independent claim covers a retractable needle syringe assembly with a liquid-tight gasket seal, a sealed needle hub, and a needle latch assembly in which spaced-apart first and second latching tabs are plastically deformed to release the needle for retraction.

Across the independent claim scope, the core coverage combines a liquid-tight gasket seal and a sealed needle hub that prevents leakage during injection with a needle latch assembly where plastically deformable first and second latching tabs release the needle for retraction, while remaining spaced from the gasket during gasket compression.

Stated Advantages

Documented Applications