SYRINGE AND METHOD FOR DISPENSING A LIQUID

Abstract

The present invention relates to a syringe for dispensing a liquid, the syringe (1) comprising: a barrel (10) including a first end (12) and a second end (14) opposite the first end (12), wherein said barrel (10) is provided with a discharge opening (18) at or near said second end (14) and wherein at least one first chamber (26) is defined inside said barrel (10), with said first chamber (26) for receiving said liquid to be dispensed through said discharge opening (18), wherein a plunger (28) is received within said barrel (10), wherein said plunger (28) supports an element (30) that is both translationally movable with regard to the barrel (10) and translationally movable with regard to the plunger (28), wherein the movement of aid element (30) is controllable independently from the movement of said plunger (28), and to a method.

Claims

1. A syringe for dispensing a liquid, the syringe comprising: a barrel including a first end and a second end opposite the first end, wherein: the barrel is provided with a discharge opening at or near the second end and at least one first chamber is defined inside the barrel, with the first chamber configured for receiving the liquid to be dispensed through said discharge opening, a plunger is received within the barrel, the plunger supports an element that is both translationally movable with regard to the barrel and translationally movable with regard to the plunger, and the movement of the element is controllable independently from the movement of the plunger.

2. The syringe according to claim 1, wherein the element supported by the plunger is a rod.

3. The syringe according to claim 2, wherein a length of the rod is larger than a length of the plunger.

4. The syringe according to claim 1, wherein the plunger is provided with a through hole, wherein the element supported by the plunger extends through the through hole into the first chamber.

5. The syringe according to claim 1, wherein the plunger is provided with both a piston head and a piston rod.

6. The syringe according to claim 5, wherein the piston rod is hollow and wherein the rod extends through the piston rod.

7. The syringe according to claim 1, wherein the plunger and/or said piston head and/or the piston rod is in sealing engagement with the element and/or wherein the piston head or piston rod is in sealing engagement with the barrel.

8. The syringe according to claim 1, wherein the plunger and the element supported by the plunger are configured such that longitudinal displacement of the plunger by a predetermined length towards the first end enlarges a volume of the first chamber to a greater extent than a subsequent longitudinal displacement of the element supported by the plunger by the same predetermined length towards the second end reduces the volume of the first chamber.

9. The syringe according to claim 5, wherein said piston head extends from said barrel to said rod, seen in a radial direction of said barrel and rod, respectively.

10. The syringe according to claim 5, wherein the piston head is interrupted by the piston rod such that a first member of the piston head extends from the barrel to a radially outer surface of the piston rod, and a second member of the piston head extends from a radially inner surface of the piston rod to said rod, seen in a radial direction of the barrel and rod, respectively.

11. A syringe for dispensing a liquid, the syringe comprising: a barrel including a first end and a second end opposite the first end, wherein the barrel is provided with a discharge opening at or near the second end; a plunger provided in the barrel, wherein at least one first chamber is defined inside the barrel by means of the plunger, with the first chamber configured for receiving the liquid to be dispensed through the discharge opening; a dosing device configured to dose a predetermined volume of the liquid contained in the first chamber and configured to dispense the dose through the discharge opening, wherein the dosing device is different from the plunger, and wherein the dosing device has at least one state in which it is movable with respect to both the barrel and the plunger.

12. The syringe according claim 11, wherein an element supported by the plunger is a member of the dosing device or is the dosing device.

13. The syringe according to claim 12, wherein: a first position of the element supported by the plunger and/or a first position of the dosing device is defined by means of a first locking device for the element supported by the plunger and/or for the dosing device, a second position of the element supported by the plunger and/or a second position of the dosing device is defined by means of a second stop and/or by means of a second locking device for the rod and/or for the element supported by the plunger and/or for the dosing device, and a distance between the second position and the first position defines the dose in connection with the shape and/or dimensions of the element supported by the plunger and/or the dosing device.

14. A method for dispensing a liquid out of a syringe, wherein the syringe comprises a barrel provided with a discharge opening and a plunger received within the barrel, the method comprising: dosing and dispensing a predetermined volume of a liquid of liquid contained in the first chamber, wherein the plunger is held in position with respect to the barrel upon the dosing and/or dispensing.

15. The method of claim 14, wherein the predetermined volume is predetermined by means of a first stop and/or by means of a first locking device, on the one hand, and by means of a second stop and/or by means of a second locking device, on the other hand.

Description

[0063] An exemplary embodiment of the invention will now be described with reference to the accompanying drawings in which:

[0064] FIG. 1 shows a view of an exemplary syringe according to the invention.

[0065] FIG. 2 shows the embodiment of FIG. 1, with both the plunger and the both the plunger and the element (rod) supported by the plunger further moved towards the second end of the barrel, when compared to the position of FIG. 1,

[0066] FIG. 3 shows the embodiment of FIGS. 1 and 2, with both the plunger and the element (rod) supported by the plunger further moved towards the second end the barrel, when compared to the positions of FIGS. 1 and 2, wherein the rod is in a position on a fourth stop (not shown, but shown in FIG. 5);

[0067] FIG. 4 shows the embodiment of FIGS. 1 through 3, with both the plunger in the same position as shown in FIG. 3, and with the element (rod) supported by the plunger further moved towards the second end the barrel and being in a second stop position.

[0068] For the avoidance of doubt, the skilled person will appreciate that in this specification, the terms up, down, front, rear, upper, lower, width, etc. refer to the orientation of the components as found in the syringe when installed for normal use as shown in the Figures.

[0069] FIG. 1 shows a syringe 1 for dispensing a liquid.

[0070] The syringe 1 comprises a barrel 10 including a first end (rearward end) 12 and a second end (forward end) 14 opposite the first end 12. The barrel 10 is of a cylindrical shape defining an inner space 16.

[0071] The barrel 10 is further provided with a discharge opening 18 and discharge passage 20, respectively, to which a needle 22 can be connected.

[0072] Secured to the discharge end (second end) 14 of the barrel 10 is a connecting collar 24 of a hypodermic needle 22.

[0073] The skilled person will appreciate that the hypodermic needle connecting collar 24 may be a simple friction fit with the discharge end 14 of the barrel 10, or it may be adhered to the discharge end 14 of the barrel 10, or it may be a locking collar, such as a Luer-Lock collar. The connection of hypodermic needles 22 to syringe barrels 10 is well known in the art and will not be described in detail herein. The invention can, however, also used without a needle or with another type of needle or fixing device for a needle.

[0074] A first chamber 26 is defined inside said barrel 10 and forms a part of the inner space 16, respectively. Said first chamber 26 can be filled with a liquid to be dispensed through said discharge opening 18 at a later stage.

[0075] A plunger 28 is received within said barrel 10, wherein said plunger 28 supports an element 30 that is both translationally movable with regard to the barrel 10 and translationally movable with regard to the plunger 28, wherein movement said element 30 is controllable from outside of the barrel 10 and/or is controllable independent from said plunger 28 and independently from movement of said plunger 28, respectively. For the purpose of realizing the latter, the element 30 extends to the outside of the barrel 10 in this example, wherein element 30 is a rod 30 in this example.

[0076] Plunger 28 comprises a flange 32 on its rearward end and at the rearward end to the piston rod 40, respectively, which extends perpendicular to the longitudinal axis 34 of the plunger 28 and rod 30 and barrel 10, respectively. Flange 32 may be ring-shaped. Piston rod 40 may have a cruciform cross section which terminates in said flange 32 at rearward end of the piston rod, such that the rearward facing surface of the flange 32 forms a pull and push surfaces for the plunger 28.

[0077] In the direction of the longitudinal axis 34, the rod 30 is longer than the plunger 10.

[0078] Rod 30 comprises a flange 36 on its rearwards end, which extends perpendicular to the longitudinal axis 34 of the plunger 28 and the rod 30 and the barrel 10, respectively. Flange 36 may have a circular shape.

[0079] Plunger 28 comprises a piston head 38 and a piston rod 40, with the diameter of the piston head 38 being larger that the diameter of the piston rod 40. In an alternative embodiment the diameter of the plunger 28 may be constant, apart from the flange 36.

[0080] Plunger 30 is provided with a through hole 41 that extends through the piston rod 40 and through the piston head 38 (and through the flange 32, if present) in the direction of the longitudinal axis 34. Rod 30 extends through said through hole 41.

[0081] Barrel 10 comprises a flange 42 on its rearwards end (first end) 12 which extends perpendicular to the longitudinal axis 34. Flange 42 may be ring-shaped.

[0082] Syringe 1 comprises a (first) locking device 44 for locking the rod 30 to the plunger 28. Said (first) locking device 44 may is releasable and is arranged such that after release of (said first) locking device 44, the rod 30 may move relative to the plunger 28 in the direction of the second end 14 of the barrel 10. Locking device 44 may prevent movement of the translational element (rod) 30 relative to the plunger 28 before the fourth stop (not shown, but shown in FIG. 5) is reached. This ensures that the translational element remains in the position relative to the plunger 28 until the priming step is completed and the plunger has engaged a fourth stop.

[0083] The rearward end first end) 12 of the barrel 10 provides a (third) stop, which is a stop for the plunger 28 and via the plunger 28 and the locking device 44 is a releasable stop for the rod 30, respectively. In this respect, the flange 32 may come into contact with the flange 42, thereby blocking further motion of the plunger 28 in the direction towards the second end 14 relatively to the barrel 10.

[0084] The rearward end of the plunger 28 and the flange 32, respectively, provide a (second) stop, which is a (second) stop for the rod 30. In this respect, the flange 36 may come into contact with the flange 32, thereby blocking further motion of the rod 30 in the direction towards the second end 14 relatively to the plunger 28.

[0085] When the rod 30 is held in position at or on the plunger 28 by means of the (first) locking device 44, said stop position at the first stop may define a first position of the rod 30, and said stop position at the second stop may define a second position of the rod 30.

[0086] By means of the various positions and states of the syringe 1 shown in FIGS. 1 to 4, respectively, an exemplary operation of an exemplary embodiment of the syringe according to the present invention, and an exemplary embodiment of the method according to the present invention will be described:

[0087] When compared to FIGS. 2 to 4, FIG. 1 show both plunger 28 and rod 30 in a maximum retracted position, where the locking device 44 is in engagement so that the movement of the plunger 28 causes respective movement of the rod 30. The plunger 28 and the rod 30, connected by the locking device 44 to each other, may have been moved to said position from a fully inserted position (i.e. combined unit of plunger 28 and rod 30 (for example maximum) inserted into barrel 10) in order to suck a liquid through the discharge opening 18 into the first chamber 26.

[0088] FIG. 2 shows a position and state of the syringe 1, respectively, that may be passed upon sucking a liquid through the discharge opening 18 into the first chamber 26, as well as upon moving in opposite direction towards the position and state of the syringe 1, respectively, which is shown in FIG. 3. In FIG. 2 the locking device 44 is in engagement.

[0089] FIG. 3 shows a position and state of the syringe 1, respectively, in which the first stop 44 is reached. Particularly, the flange 32 of the plunger 28 is in contact with the flange 36 of the barrel 10, and the rod 30 is thus also in a stop position, since the locking device 44 holds the rod 30 in position with regard to the plunger 28.

[0090] Upon movement from the position shown in FIG. 1 to the position shown in FIG. 3, superfluous liquid as well as air can be removed from the first chamber thanks to the design not requiring very small diameters of the barrel 10, but allowing dispensing very small volumes thanks to the rod 30 in this exemplary embodiment.

[0091] By further pushing the rod 30 in the second direction (indicated by arrow 46) and applying a respective force sufficient to overcome the holding force of the locking device 44 (for example, locking device may have a recess in combination with spring biased ball engaging said recess), the rod 30 continues movement in the second direction. It must be noted that other locking devices 44 may be used in the present invention, which might, for example, require actuating a release member instead of applying a force higher that a holding force.

[0092] Upon this continued movement of the rod in the second direction, the intended dose of liquid fluid is dispensed.

[0093] In order to ensure exactly the predetermined dose to be dispensed, a second (stop position) of the rod 30 is provided, as shown in FIG. 4.

[0094] This is exemplary realized in this embodiment by providing a stop 32, 42 for the rod 30 and the flange 36 of the rod 36, respectively, for example by means of the flange 32 being in contact with a blocked by flange 42 with regard to movements in the second direction.

[0095] FIG. 5 shows some further exemplary features (particularly first, second, third, and fourth further features) that may be singly or in any combination used in the embodiment as shown in FIGS. 1 to 4, and in a respective method, respectively.

[0096] As a first further feature, FIG. 5 shows a first seal 48 sealing the piston head 38 against the inner circumferential wall of the barrel 10. Said first seal 48 may be received in a first groove provided in the outer circumference of said piston head 38.

[0097] As a second further feature, FIG. 5 shows a second seal 50 sealing the piston head 38 and/or plunger 28, respectively, against the outer circumferential wall of the rod 30. Said second seal 50 may be received in a second groove provided in the inner circumference of said piston head 38 and plunger 28, respectively.

[0098] As a third further feature, FIG. 5 shows a fourth stop and locking device 52, respectively, for stopping and/or releasably locking plunger 28 and piston, respectively, to the barrel 10.

[0099] As a fourth further feature, FIG. 5 shows that the discharge opening 18 defines a second chamber. The outer dimensions of the second chamber may substantially correspond to the outer dimensions of the facing end section of the rod 30 so that the rod 30 can enter the second chamber.

[0100] For example, the invention may be used for delivering of an ophthalmic solution (liquid).

[0101] Moreover, the syringe may be provided with dose marks.

[0102] It must be noted that the end plate 54 of barrel 10 may be attached to the outer shell 56 of the barrel 56 after the plunger 28 has been inserted into the outer shell of the barrel 10, in order to allow mounting the syringe. However, there are alternative options, like diving the outer shell 56 into two separate parts to be attached to each other after the piston rod 40 has passed the through hole 41 and, thereafter, the piston rod has been attached to the piston head 38, or the like. In any case, preferably, the barrel is made to be one piece after the plunger 28 has passed the hole 41.

REFERENCE NUMERALS

[0103] 1 syringe [0104] 10 barrel [0105] 12 first end (rearward end) of 10 [0106] 14 second end (forward end) of 10 [0107] 16 inner space of 10 [0108] 18 discharge opening in 10 [0109] 20 discharge passage [0110] 22 needle [0111] 24 connecting collar of 22 [0112] 26 first chamber [0113] 28 plunger [0114] 30 element supported by 28, rod [0115] 32 flange of 28 [0116] 34 longitudinal axis of 10, 28, 30 [0117] 36 flange of 30 [0118] 38 piston head [0119] 40 piston rod [0120] 41 through hole in plunger [0121] 42 flange of 10 [0122] 44 first locking device [0123] 46 second direction [0124] 48 first seal [0125] 50 second seal [0126] 52 fourth locking device [0127] 54 end plate of 10 [0128] 56 outer shell of 10