WO2006128915A1

WO2006128915A1 - Multi-cylinder syringe

Info

Publication number: WO2006128915A1
Application number: PCT/EP2006/062892
Authority: WO
Inventors: Eckhard Schwöbel; Daniel Vuille
Original assignee: Schwoebel Eckhard; Daniel Vuille
Priority date: 2005-06-02
Filing date: 2006-06-02
Publication date: 2006-12-07
Also published as: EP1890752A1

Abstract

The invention relates to a multi-cylinder syringe (10) for a plurality of substances (20, 24), which comprises at least one external syringe cylinder (12), which has a syringe outlet (26), and an inner syringe cylinder (14), which is housed, at least partially, in the external cylinder (12), and which can be displaced in the longitudinal direction from a proximal extended state (fig. 3) into a distal inserted state (fig. 4). A resilient catching element (38), which pushes against a stop (29) when the multi-cylinder syringe (fig. T) is in the extended state, is provided and as a result prevents the multi-cylinder syringe from being pushed together when in the inserted state (fig. 4). The inner syringe cylinder (14) comprises a front piston (30) which is in sealing contact with the inner wall (32) of the external syringe cylinder (12), in order to simplify the mixing and injecting of the substances (20, 24). The front piston (30) comprises a pressure relief valve (46) or a non-return valve, which connects the cavity (22) of the inner syringe cylinder (14) to the cavity (18) of the external syringe cylinder (12) in a distal manner in relation to the front piston (30). The substance (20) of the external syringe cylinder (12) is contained in the cavity (18) in a distal manner from the front piston (30), and when the rear cylinder (16) is displaced form the extended state (fig. 2) into the inserted state (fig. 3), a substance (24) which is contained in the inner syringe cylinder (14) can be pressed into the cavity (18) in a distal manner from the front piston (30). The catching element (38) is arranged on the inner syringe cylinder (14) and is outwardly resilient when the syringe cylinder (14) is in the extended state (fig. 2) and blocks the inner syringe cylinder (14) from displacing. The invention also relates to a corresponding method which is used to mix several substances in a multi-cylinder syringe.

Description

Multi-cylinder syringe

The invention relates to a multicylinder multi-cylinder syringe having at least one outer syringe barrel having a syringe outlet and an inner syringe barrel at least partially contained within the outer syringe barrel and slidable longitudinally from a proximal extended condition to a distal retracted condition is. The invention further relates to a method for mixing two substances in such a multi-cylinder syringe.

With multi-cylinder syringes, substances to be injected as a substance mixture can be stored separately and mixed before injection. Such substances may be, for example, freeze-dried medicaments which are to be mixed with a liquid prior to injection. Typically, multi-cylinder syringes are designed as two-cylinder syringes, ie as syringes with two cylinders pushed one inside the other, each of the two cylinders containing one of the substances to be mixed. Here, the two substances can be both a powder and a liquid and two liquids.

EP 0 005 939 A1, to which the preambles of the two main claims refer, relates to a multi-chamber syringe having an outer housing in which a cylinder is slidably guided in the longitudinal direction. Between the cylinder and the outer housing a sealed with two plugs cavity is formed, in which a first substance is contained. The interior of the cylinder contains a second substance. In the cylinder, a piston ram is guided, wherein the piston ram has latching spring arms which hold in the extended state of the piston ram outward springs and the piston ram against a flange of the cylinder. When pulling out the cylinder from the outer housing creates a cavity with negative pressure. The piston ram is prevented by the spring arms in the locked state from slipping due to the negative pressure in the cylinder. After actuation of the spring arms of the stamp can be moved back and forth within the cylinder, wherein the two substances are mixed by repeated actuation of the punch. Subsequently, the punch is pulled out of the cylinder until the spring arms engage, whereby the mixture of the two substances is completely sucked into the interior of the cylinder. After advancing the cylinder in the outer housing and after actuation of the spring arms, the piston ram can be advanced to press the mixture of the two substances from the cylinder interior by a needle attached to a needle hub of the outer housing.

The invention has for its object to provide a multi-cylinder syringe, which simplifies the mixing and injecting several substances. Furthermore, lies the _ O -

Invention the task of providing a corresponding method for mixing a plurality of substances.

The multi-cylinder syringe according to the invention is defined by the features of claim 1.

The multi-cylinder syringe is characterized in that the inner syringe barrel has a front piston sealingly contacting the inner wall of the outer syringe barrel. The front piston has a relief valve or check valve which connects the cavity of the inner syringe barrel to the cavity of the outer syringe barrel distal to the forward plunger, the substance of the outer syringe barrel being contained in the cavity distal to the forward plunger. By displacing the rear piston from the extended to the retracted state, a substance contained in the inner syringe barrel can be pressed into the cavity distal to the front bulb. The locking element is arranged on the inner syringe cylinder and springs in the extended state of the inner syringe barrel to the outside and thereby blocks the inner syringe barrel against advancement in the outer cylinder.

The method according to the invention for mixing a plurality of substances in a multi-cylinder syringe is defined by the features of claim 9. The method is characterized by the steps:

a) generating a negative pressure in the cavity of the outer syringe barrel by partially withdrawing the inner syringe barrel from the outer syringe barrel,

b) blocking the inner syringe barrel relative to the outer syringe barrel in the extended state by releasing a latching element arranged on the inner syringe barrel, c) inserting the second substance into the cavity of the outer syringe barrel by advancing the rear bulb into the inner syringe barrel,

d) canceling the blocking of the inner syringe barrel by pressing in the latching element,

e) pressing out the substance mixture from a syringe outlet of the outer syringe barrel by inserting the inner syringe barrel into the outer syringe barrel.

With the multi-cylinder syringe according to the invention and the corresponding method, a simplified mixing of several substances and injection of the substance mixture is made possible. For mixing the substances, only the inner syringe barrel is to be pulled out of the outer syringe barrel in the proximal direction until the latching element engages on the outer syringe barrel, and then the rear plunger is to be pushed completely into the inner syringe barrel in the distal direction. For injecting the resulting substance mixture, the latching element is to be pressed against the inner syringe barrel and, for example, by pushing the rear plunger in the distal direction, insert the inner syringe barrel into the outer syringe barrel, whereby the front plunger forces the substance mixture out of the syringe outlet.

The latching element may be formed of at least one elongate elastic spring arm which is arranged parallel to the inner syringe barrel, wherein the proximal end of the spring arm is connected to the inner syringe barrel and wherein the distal end protrudes from the inner syringe barrel in the relaxed state of the spring arm. The distal end of the spring arm abuts in the extended state of the inner syringe barrel against a stop of the outer syringe barrel, whereby an insertion the inner syringe barrel is prevented in the outer syringe barrel. The stop may be formed by a handle plate at the proximal end of the outer syringe barrel. The outer syringe barrel may have an inner ring proximal to the forward piston that limits movement of the forward piston in the outer syringe barrel in the proximal direction, and the inner syringe barrel may have a projection cooperating with the inner ring proximal to the forward piston and distal to the inner ring , The inner syringe barrel can only be pulled out of the outer syringe barrel until the protrusion abuts against the inner ring.

The check valve allows, for example, a flow in the distal direction, d. H. from the inner syringe barrel into the outer syringe barrel, and prevents it from flowing in the reverse direction. The pressure relief valve allows a flow in the distal and in the proximal direction only when a certain pressure is exceeded. The pressure relief valve is preferably formed by a slot in an elastic membrane in the piston surface of the front piston, the membrane of the cavity of the inner syringe barrel from the cavity of the outer Syringe cylinder separates. Alternatively, the pressure relief valve may be formed as a frangible membrane, which is destroyed when a certain pressure is exceeded to produce an opening between the cavity of the inner syringe barrel and the cavity of the outer syringe barrel.

The inner syringe barrel and the rear piston preferably have cooperating locking lugs, which engage in the inserted state of the rear piston and prevent displacement in the proximal direction. Here, for example, a detent on the cavity inner wall of the inner syringe barrel and another detent on the outside of the rear piston is formed. The rear piston is inserted into the inner syringe barrel until the locking lugs engage in one another and engage Prevent removal of the rear piston from the inner syringe barrel in the proximal direction. When the latches are engaged, the person operating the multicylinder syringe knows that the rear piston is fully inserted into the inner syringe barrel and the substance contained within the inner syringe barrel is completely squeezed out. In addition, the latching lugs allow in the locked state, a back and forth displacement of the rear piston together with the inner syringe barrel in the outer syringe barrel to better mix the mixture of substances in the cavity distal to the front piston.

The syringe outlet is preferably sealed with an airtight, multi-reusable closure, thereby allowing negative pressure to be established in the outer syringe barrel by withdrawing the inner syringe barrel from the outer syringe barrel. By subsequently removing the closure from the syringe outlet, the syringe outlet is released to allow the mixture of substances to be forced through the syringe outlet.

In the following an embodiment of the invention will be explained in more detail with reference to FIGS.

Show it :

1 is a longitudinal section of the multi-cylinder syringe with partially extended inner syringe barrel and partially extended rear piston,

2 shows the longitudinal section of Figure 1 with fully extended inner syringe barrel, 3 with the longitudinal section according to FIG. 2 with the rear piston fully inserted, FIG.

4 shows the longitudinal section of Figure 3 with fully inserted inner syringe barrel, and

Fig. 5 is a plan view of the front piston.

The embodiment shown in the figures shows a multi-cylinder syringe 10 with an outer syringe barrel 12, an inner syringe barrel 14 and a rear piston 16. The outer syringe barrel contains a cavity 18 for a first substance 20 and the inner syringe barrel 14 contains a cavity 22 for a second Substance 24. The multi-cylinder syringe 10 is designed as a two-cylinder syringe with two cylinders 12, 14 and two cavities 18, 22 for two substances 20, 24.

The outer syringe barrel 12 has an elongated cylindrical shape with a forward distal 70 and a posterior proximal end 72. Provided at the distal end 70 is a syringe outlet 26 in the form of a needle hub for securing a syringe needle and a sealing closure cap. At the proximal end 72 of the outer syringe barrel 12 in a plane transverse to the longitudinal axis of a handle plate 28 integrally formed. The handle plate 28 forms a stop 29 for the locking elements 38. Upon actuation of the rear piston 16 with the thumb, the handle plate 28 allows for supporting the index finger and middle finger.

The inner syringe barrel 14 has an elongated and substantially cylindrical shape fitting into the cavity 18 of the outer syringe barrel 12 with a distal forward end 74 and a proximal rearward end 76. The distal end 74 of the inner syringe barrel 14 is integral with a forward piston 30 formed. Of the Front piston 30 has a sealing ring 31, which sealingly contacts the inner wall 32 of the cavity 18 of the outer syringe barrel 12, so that neither air nor the substances 20, 24 between the front piston 30, seal ring 31 and cavity inner wall 32 can escape. The cavity 18 of the outer syringe barrel 12 is defined by the inner wall 32, the distal end 74 of the outer syringe barrel 12, and the forward piston 30. The volume of the cavity 18 is variable depending on the position of the forward piston 30 within the outer syringe barrel 12 The inner syringe barrel 14 has, proximal of the forward piston 30, an annular projection 34 which cooperates with an inner ring 36 formed on the inner wall 32 of the outer syringe barrel 12 proximal of the forward piston 30 for limiting the movement of the inner syringe barrel 14 in the proximal direction. The movement of the inner syringe barrel 14 is limited by the annular projection 34 abutting the inner ring 36.

The inner syringe barrel 14 has two latching elements 38 formed on its outer lateral surface 44, each in the form of an elongated elastic spring arm. Each spring arm has a proximal end 40 and a distal end 42, wherein each proximal end 40 of the lateral surface 44 is integrally formed. Each distal end 42 springs outward in the radial direction transversely to the longitudinal axis of the inner syringe barrel 14, d. H. in the relaxed state of the relevant spring arm, the distal end 42 protrudes from the lateral surface 44 and detents in the fully extended state shown in Figures 2 and 3 of the inner syringe barrel 14 against the handle plate 28 of the outer syringe barrel 12 and prevents insertion of the inner syringe barrel 14 in the outer syringe barrel 12th

In the cavity 18 facing the piston surface 48 of the front piston 30, a pressure relief valve 46 is arranged, which connects the cavity 18 with the cavity 22. FIG. 5 shows the front piston 30 with the valve 46 in plan view. The pressure relief valve 46 is a double slot 52 in an elastic Membrane 50 formed in the piston surface 48. If the pressure in one of the two cavities 18, 22 exceeds a certain value with respect to the pressure in the other cavity, the double slot 52 in the valve 46 is opened by the overpressure, thereby opening the valve 46.

On the inner wall 54 of the cavity 22 of the inner syringe barrel 14 is a detent 56 with a pointing in the distal direction of the attack surface 58 and with a pointing in the proximal direction inclined surface 60. On the piston rod 68 of the rear piston 16 is on the outside one of the locking lug 56 corresponding locking lug 62nd attached. The latching lug 62 has an engagement surface 64 facing in the proximal direction and an obliquely pointing inclined surface 66. When the rear piston 16 is inserted into the inner syringe barrel 14, the inclined surfaces 60, 66 of the two latching lugs 56, 62 slide past one another until the latching lugs 56 , 62 click into each other, d. H. the engagement surfaces 58, 64 opposite each other and engage. Pulling out the rear piston 16 from the inner syringe barrel 14 in the proximal direction is then prevented.

The function of the multi-cylinder syringe is described below with reference to the figures:

FIG. 1 shows the multicylinder syringe 10 in delivery condition. The syringe outlet 26 is sealingly and firmly closed with a screwed on closure cap 82. In the cavity 18 of the outer syringe barrel 12, the first substance 20 is included. In the cavity 22 of the inner syringe barrel 14, the second substance 24 is included. The first substance 20 is shown by dashed lines in FIGS. 1 to 4 and the second substance 24 by dots. The inner syringe barrel 14 is half inserted into the outer syringe barrel 12 and the rear plunger 16 is half inserted into the inner syringe barrel 14. For mixing the two substances 22, 24, as shown in FIG. 2 by the arrow A, the inner syringe barrel 14 is pulled out of the outer syringe barrel 12 in the proximal direction until the annular protrusion 34 abuts against the inner ring 36 and the inner syringe barrel 14 thereby prevented from further movement in the proximal direction. By withdrawing the inner syringe barrel 14 and the front plunger 30 from the outer syringe barrel 12, the cavity 18 of the outer syringe barrel 12 is increased. Due to the sealing closure of the front piston 30 on the inner wall 32 and the closure cap 82 on the syringe outlet 26, a negative pressure is created in the cavity 18 of the outer syringe barrel 12. In the extended state of the inner syringe barrel 14 shown in Figure 2, the two locking elements 38 in the direction of arrows B spring outward and engage with their distal ends 42 on the stop 29 of the handle plate 28, whereby insertion of the inner syringe barrel 14 in the distal direction is prevented in the outer syringe barrel 12.

In the enlarged cavity 18, the second substance 24 is then inserted by operating the rear piston 16 in the direction of the arrow C shown in Figure 3, whereby the second substance 24 is pressed through the slot 52 of the valve 46. The second substance 24 mixes with the first substance 20 in the cavity 18 of the outer syringe barrel 12. The locking elements 38 latched to the grip plate 28 prevent the inner syringe barrel 14 from being displaced in the distal direction when the posterior piston 16 is inserted in the distal direction ,

In the fully inserted state of the rear piston 16 in the inner syringe barrel 14 shown in FIG. 3, the latching lugs 56, 62 engage one another, so that the piston 16 is actuated by multiple actuation of the rear piston 16, as represented by the double arrow E in FIG proximal direction of the inner syringe barrel 14 and the front piston 30 in the direction of the double arrow E in Figure 3 in the distal and in the proximal direction back and be pushed to mix the substances 20, 24 better. To inject the mixture of the two substances 20, 24 into a patient, the cap 82 is removed from the syringe outlet 26 by unscrewing and instead a syringe needle 84 is screwed onto the syringe outlet 26.

Figure 4 shows the screwed syringe needle 84. In order to squeeze the substance mixture through the syringe needle 84 from the cavity 18, the locking elements 38 are first pressed in the direction of arrows D shown in Figure 3 and so the inner syringe barrel 14 released. Subsequently, by actuating the rear piston 16 in the distal direction, as shown in Figure 4 by the arrow F, operated and so the inner syringe barrel 14 is displaced in the distal direction. When inserting the inner syringe barrel 14, the piston surface 48 of the front piston 30 presses the mixture of the two substances 20, 24 out of the cavity 18 through the syringe outlet 26 and the syringe needle 84.

Claims

claims

A multi-cylinder multi-substance syringe (10) (20,24) having at least one outer syringe barrel (12) having a syringe outlet (26) and an inner syringe barrel (14) at least partially in the outer syringe barrel (12) ) and is longitudinally displaceable from a proximal extended state (Figs. 2, 3) to a distal retracted state (Fig. 4);

the inner syringe barrel (14) including a posterior piston (16) slidable longitudinally from a proximal extended state (Figs. 1, 2) to a distal retracted state (Figs. 3, 4), and

wherein a resilient latching element (38) is provided, which in the extended state (Fig. 2) of the multi-cylinder syringe (10) abuts against a stop (29) and thereby prevents pushing the multi-cylinder syringe (10) in the inserted state (Fig. 4) .

d a d u r c h e s e n c i n e s, d a s s

the inner syringe barrel (14) has a front piston (30) sealingly contacting the inner wall (32) of the outer syringe barrel (12),

the front piston (30) having a relief valve (46) or a check valve connecting the cavity (22) of the inner syringe barrel (14) to the cavity (18) of the outer syringe barrel (12) distal to the forward piston (30), wherein the substance (20) of the outer syringe barrel (12) in the Cavity (18) is contained distally of the front piston (30), and wherein by moving the rear piston (16) from the extended state (Fig. 2) to the retracted state (Fig. 3) in the inner syringe barrel (14) contained substance (24) in the cavity (18) distal to the front piston (30) is pressed, and

the detent element (38) is arranged on the inner syringe cylinder (14) and in the extended state (Fig. 2, Fig. 3) of the inner syringe barrel (14) springs outwards and thereby blocks the inner syringe barrel (14) from advancing.

2. Multi-cylinder syringe (10) according to claim 1, characterized in that the latching element (38) is formed from at least one elongate elastic spring arm, which is arranged parallel to the inner syringe barrel (14), wherein the proximal end (40) of the spring arm with the inner syringe barrel (14) is connected and the distal end (42) protrudes from the inner syringe barrel (14) in the relaxed state of the spring arm.

3. Multi-cylinder syringe (10) according to claim 1 or 2, characterized in that the stop (29) by a handle plate (28) at the proximal end (72) of the outer syringe barrel (12) is formed.

4. Multi-cylinder syringe (10) according to one of claims 1 to 3, characterized in that the outer syringe barrel (12) proximal to the front piston (30) has an inner ring (36) which controls the movement of the front piston (30) in the outer syringe barrel (12) limited in the proximal direction.

5. Multi-cylinder syringe (10) according to claim 4, characterized in that the inner syringe barrel (14) proximal of the front piston (30) and distal of the inner ring (36) has a protruding projection (34) which cooperates with the inner ring (36) so that the movement of the inner syringe barrel (10) in the outer syringe barrel (12) is limited in the proximal direction.

6. Multi-cylinder syringe (10) according to any one of claims 1 to 5, characterized in that the pressure relief valve (46) through a slot (52) in an elastic membrane (50) in the piston surface (48) of the front piston (30) is formed wherein the membrane (50) separates the cavity (22) of the inner syringe barrel (14) from the cavity (18) of the outer syringe barrel (12).

7. A multicylinder syringe (10) according to any one of claims 1 to 6, characterized in that the inner syringe barrel (14) and the rear piston (16) have cooperating detents (56,62) which in the retracted state (Fig. 3, Fig 4) of the rear piston (16) and prevent displacement in the proximal direction.

8. Multi-cylinder syringe (10) according to any one of claims 1 to 7, characterized in that the syringe outlet (26) with an airtight multi-reusable closure (82) is closed.

A method of mixing a plurality of substances in a multi-cylinder syringe (10) having an outer syringe barrel (12) having a syringe outlet (26) filled with a first substance (20) and an inner syringe barrel (14) at least partially contained within the outer syringe barrel (12) and longitudinally slidable and filled with a second substance (24), the inner syringe barrel (14) having a front piston (11) sealingly abutting the inner wall (32) of the outer syringe barrel (12). 30) and includes a rear piston (16), marked by the steps:

a) generating a negative pressure in the cavity (18) of the outer syringe barrel (12) by partially withdrawing the inner syringe barrel (14) from the outer syringe barrel (12),

b) blocking the inner syringe barrel (14) relative to the outer syringe barrel (12) in the extended state (FIG. 2) by releasing a latching element (38) arranged on the inner syringe barrel (14),

c) inserting the second substance (24) into the cavity (18) of the outer syringe barrel (12) by advancing the rear bulb (16) into the inner syringe barrel (14),

d) canceling the blocking of the inner syringe barrel (14) by pressing in the latching element (38),

e) pressing out of the substance mixture from the syringe outlet (26) by inserting the inner syringe barrel (14) into the outer syringe barrel (12).

10. The method according to claim 9, characterized in that between steps a) and b), the following step is carried out:

Limiting proximal movement of the inner syringe barrel (14) by striking a projection (34) of the inner syringe barrel (14) against an inner ring (36) on the inner wall (32) of the outer syringe barrel (12).

11. The method according to claim 9 or 10, characterized in that after step c) and before step d), the following step is carried out:

Blocking the rear piston (16) in the inner syringe barrel (14) against displacement in the proximal direction.

12. The method according to any one of claims 9 to 11, characterized in that prior to step a) the following step is carried out:

airtight closing of the syringe outlet (26).

13. The method according to any one of claims 9 to 12, characterized in that after step c) and before step e), the following step is carried out:

Opening the syringe outlet (26).

14. The method according to any one of claims 9 to 13, characterized in that before step c), the following step is carried out:

Opening a pressure relief valve (46) in the piston surface (48) of the front piston (30).