EP0440846B1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Two-compartment syringe and application process
Assignee: Apotheker Vetter and Company Arzneimittel GmbH Ravensburg
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Filing: 1990-02-07
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Granted: 1993-06-09
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Expires: 2010-02-07
Abstract
Abstract The invention relates to a syringe for medical purposes, with a syringe barrel (1) designed at the one end for the attachment of an injection needle (2), and with a syringe piston (3) which is displaceable in the syringe barrel (1), and with a stopper (4) which is arranged between the needle attachment end (5) and the syringe piston (3) and thus forms the two chambers (6, 7) of a two-chamber syringe. In the needle-side chamber (6) the circumferential surface of the syringe barrel (1) is provided with an axially extending cross-section widening which forms a bypass (8) and via which the two chambers (6, 7) are connected to one another when the stopper (4) is moved into the area of the bypass (8). A damping part (9) serving as a piston brake is arranged at the cylinder end lying opposite the needle attachment end (5), this damping part (9) cooperating with a stop device (13, 14) arranged on the piston rod (10) in such a way as to permit a complete and thorough mixing of active substance and solvent. <IMAGE>
Inventors
- 👤 Udo J. Vetter
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-06 19:42
CPC Classifications
A; A61; A61M; A61M5/00; A61M5/178; A61M5/31; A61M5/315; A61M5/31596; A61M5/31565; A61M5/31576; A61M5/31583; A61M5/31586
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
352 words
A method of intermixing a pharmaceutical substance which is contained in a double-chamber syringe and rose active material is disposed in dry form in the one chamber (6) which is towards the needle, and whose solvent is disposed in the other chamber (7), wherein the two chambers (6, 7) are separated from each other by a plug (4) which for intermixing of the substance with the solvent prior to application is displaceable into the region of a by-pass (8) which is provided in the syringe cylinder (1) and which extends in the axial direction thereof and whose length is greater than the axial dimension of the plug (4), wherein the plug (4) is displaced towards the needle end by way of the syringe plunger (3) which delimits the second chamber (7) and which is provided with a plunger rod (10), directly or by way of the solvent, characterised in that when the syringe is arranged vertically with the needle attachment end (5) pointing upwardly, firstly the plug (4) is displaced into the region of the by-pass (8) at a speed which is limited by apparatus considerations, that then the syringe plunger (3) is put into a condition of bearing against the plug (4) by virtue of free displaceability of the plunger rod (10) towards a front stop (14.1) and thereby the solvent is transferred into the chamber (6) at the needle side, that then the syringe plunger (3) is withdrawn again as far as a rear stop (13.1) on the plunger rod (10) and then displaced again to the front stop (14.1) so that the active material with the solvent flows back from the front chamber (6) by way of the by-pass (8) into the rear chamber (7) and then into the front chamber (6) again one or more times, until the substance is completely dissolved, and that finally after the active material is completely dissolved the front stop (14.1) on the plunger rod (10), which initially restricts the displacement of the syringe plunger (3) towards the needle end of the syringe cylinder (1) is released for application of the pharmaceutical substance.
Claim 2
Dependent Claim
26 words
A method according to claim 1 characterised in that the needle (2) is fitted when the plunger rod (10) is moved against the rear stop (13.1).
Claim 3
Dependent Claim
276 words
A syringe for medical purposes for carrying out the method according to claims 1 and 2 comprising a syringe cylinder (1) which is adapted at one end for attachment of an injection needle (2), and a syringe plunger (3) which is displaceable in the syringe cylinder (1), and a plug (4) which is disposed between the needle attachment end (5) and the syringe plunger (3) and thus forms two chambers (6, 7) of a double-chamber syringe, wherein in the chamber (6) which is towards the needle the peripheral surface of the syringe cylinder (1) is provided with an axially extending cross-sectional enlargement which forms a by-pass (8) and by way of which both chambers (6, 7) are communicated with each other when the plug is displaced into the region (8) of the by-pass (5), and further comprising a damping member (9) which serves as a plunger brake at the end of the cylinder which is opposite to the needle attachment end (5), characterised in that the damping member (9) restricts the speed of displacement of the plunger rod (10) until the plug (4) is displaced into the region of the by-pass (8) and that the plunger rod (10), for restricting the displacement stroke movement of the syringe plunger (3) between its starting position at the end of the cylinder and its condition of bearing against the plug (4) when displaced into the by-pass region, has a front stop (14.1) and a rear stop (13.1) for a co-operating portion provided at the end of the cylinder, and that the front stop (14.1) which restricts the displacement of the syringe plunger (3) towards the needle end is releasable.
Claim 4
Dependent Claim
139 words
A syringe according to claim 3 characterised in that the damping member (9) is formed with a finger support (12) which is fitted on a glass flange (11) on the side of the syringe cylinder (1) which is remote from the needle attachment end (5), and is provided with a female screwthread which is coaxial with respect to the syringe cylinder (1) for a screwthreaded shank (13) disposed on the plunger rod (10), wherein the female screwthread from the co-operating portion and the end face which is remote from the syringe cylinder forms the rear stop, and the length of the screwthreaded shank (13) is such that its end face which is remote from the syringe plunger (3) comes out of the female screwthread as soon as the plug (4) is in the middle region of the by-pass (8).
Claim 5
Dependent Claim
40 words
A syringe according to claim 4 characterised in that the front stop (14.1) is formed by the end face, which is towards the first screwthreaded shank (13), of a second screwthreaded shank (14) which also corresponds to the female screwthread.
Claim 6
Dependent Claim
69 words
A syringe according to claim 4 or claim 5 characterised in that the plunger rod (10) is provided at its end with a thread attachment (15) for a plug screwthread in the syringe plunger (3), wherein provided between the thread attachment (15) and the first screwthreaded shank (13) is a cylindrical guide portion (16) whose diameter is only slightly smaller than the minor thread diameter of the female screwthread.
Claim 7
Dependent Claim
76 words
A syringe according to claims 4 to 6 characterised in that the finger support (12) is formed by two shell halves which accommodate the glass flange (11) of the syringe cylinder (1) between them and which are provided with mutually engaging connecting elements (17), wherein the shell half which is towards the needle end is provided with an opening which embraces the syringe cylinder (1) and the other shell half is provided with the female screwthread.
Claim 8
Dependent Claim
22 words
A syringe according to claim 7 characterised in that the two shell halves are hingedly connected to each other at the edges.
References Cited (Backward Citations)
No citation records indexed.
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