Needleless injection device equipped with an improved injection nozzle

Inventors

Steinberger, Robin • VIVIEN, Gilles

Abstract

A needleless injection device includes a body forming a receptacle extending axially from an upper radial seat along an injection axis, a gas generator, a tubular reservoir containing an active ingredient and extending axially in the receptacle from an upper end to a lower end, and a nozzle for injecting the active ingredient. The nozzle is arranged at the lower end of the reservoir and has an outer thread to be screwed onto a complementary thread formed by the body. The external thread of the nozzle has an overall triangular cross-section and is delimited by an upper face, which has a first angle with respect to a radial axis perpendicular to the injection axis, and a lower face, which has a second angle with respect to the radial axis. The first angle is greater than the second angle.

Core Innovation

A needleless injection device includes a body forming a housing extending axially in a direction of injection, a gas generator, and a tubular reservoir containing an active ingredient. A lower piston is disposed below the active ingredient, and the tubular reservoir extends axially in the housing from an upper end to a lower end. A nozzle is arranged at the lower end of the tubular reservoir to inject the active ingredient along an injection axis.

The nozzle includes an external thread adapted to be screwed onto a complementary tapping formed by the body. The nozzle is configured to axially compress the reservoir on an upper radial seat of the housing, and the external thread extends axially in the direction of injection from the lower end of the tubular reservoir to a position beyond the lower end, extending around a central housing adapted to receive the lower piston.

An elastically deformable membrane extends axially in the reservoir and is configured to expel the active ingredient from the reservoir. The elastically deformable membrane has an accordion shape, and a lower surface abuts against the upper axial surface of the upper piston. The elastically deformable membrane further comprises an annular disc interposed axially between the upper end of the reservoir and the upper radial seat of the housing.

The external thread is triangular, with an upper face having a first angle and a lower face having a second angle relative to a radial axis perpendicular to the injection axis, where the first angle is greater than the second angle. The lower face is non-zero to form a flank face, and the external thread can be sawtooth shaped, with a curved portion connecting adjacent triangles.

Claims Coverage

The independent claim contains the overall needleless, gas-generator-driven injection architecture and specifies core co-operating structures, including the threaded nozzle to axially compress the reservoir and an accordion-shaped elastically deformable membrane to expel the active ingredient, while receiving further refinement through multiple inventive features in dependent claims focused on the external thread geometry and angle relationships. The inventive features are centered on triangular external thread geometry, defined angular relationships (first angle greater than second angle), and a complementary tapping interface, together with an accordion-shaped membrane and annular disc arrangement.

Overall, the claim set covers a needleless injection device using a gas generator with a threaded nozzle that axially compresses a tubular reservoir on an upper radial seat, where the external thread has a triangular section and a first-angle/second-angle relationship (first angle greater than second angle). The claims further specify an accordion-shaped elastically deformable membrane with an annular disc, and dependent features refine the nozzle thread shape and geometry through sawtooth/flank formation and a curved portion connecting adjacent triangles.

Stated Advantages

Documented Applications