§
Luxuse
Patent Intelligence
Sign In
Patent EP0229017A2 successfully refreshed from Google Patents.
← Back to Patent Explorer
EP0229017A2 Expired / Lapsed EP ⏱️ 0.0 years remaining

Arrangement in injection syringe for use once only

Assignee: Individual
•
Filing: 1987-01-06
•
Granted: —
•
Expires: 2007-01-06
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract In an injection syringe for use once only the piston rod (4) is connected to the piston (3) by claws (9) which upon pressing of the piston rod (4) against the piston (3) during injection break or become deformed to such an extent that it is no longer possible to retract the piston (3) for the purpose of refilling the syringe. The deformation is effected by means of a conical portion (l3) on the piston, said portion by wedge effect pressing the claws (9) radially outwardly when the piston rod (4) is pressed against the piston (3). The rigidity and strength of the claws (9) is adapted to the resistance experienced during injection of a liquid so that the claws will certainly be broken or otherwise brought out of engagement with the piston (ll). On the other hand the force tequired to push the piston forward in an empty syringe does not have to be sufficient to break the claws (9).

Inventors

  • 👤 Christian Sandsdalen

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-10-24 23:46
CPC Classifications
A; A61; A61M; A61M5/00; A61M5/50; A61M5/5066; A61M2005/5073

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 77 words
Arrangement in injection syringe for use once only, comprising a cylinder (l) and a piston (3) having a piston rod (4), characterised in that the piston rod (4) is connected to the piston (3) by means (9) which upon pressing of the piston rod (4) against the piston (3) during injection break or become deformed to such an extent that it is no longer possible to retract the piston (3) for the purpose of refilling the syringe.
Claim 2
Dependent Claim 77 words
Arrangement in injection syringe for use once only, comprising a cylinder (l) and a piston (3) having a piston rod (4), characterised in that the piston rod (4) is connected to the piston (3) by means (9) which upon pressing of the piston rod (4) against the piston (3) during injection break or become deformed to such an extent that it is no longer possible to retract the piston (3) for the purpose of refilling the syringe.
Claim 3
Dependent Claim 68 words
Arrangement as claimed in claim l, characterised in that the piston rod (4) at the end carries one or more claws (9) which engage an undercut surface (l0) on the piston (3), and that the piston (3) has inclined surfaces (l3) against which the claws (9) will bear when the piston rod is pressed and which therefore by wedge effect deform the claws (9) or break them away.
Claim 4
Dependent Claim 57 words
Arrangement as claimed in claim 2, characterised in that a claw (9) is provided at each of the outer ends of a yoke (8) at the end of the piston rod (4), and that the inclined surfaces with which the claws cooperate are formed by a conical portion (l3) at the rear end of the piston (3).
Claim 5
Dependent Claim 32 words
Arrangement as claimed in claim 3, characterised in that the undercut surface (l0) is formed by the rear side of a collar (ll) at the narrow end of the conical portion (l3).
Claim 6
Dependent Claim 57 words
Arrangement as claimed in any of the claims 2-4, characterised in that the claws (9) have at the base thereof an incision governing the place of rupture and are made of a material which is sufficiently brittle to cause complete breaking of the claws (9) away from the piston rod (4) due to the said wedge effect.

References Cited (Backward Citations)

No citation records indexed.

USPTO Annuity & Maintenance Windows

Maintenance schedule is calculated for granted US utility patents.

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag