AU2002311729A1 - Dispenser - Google Patents

Description

DISPENSER

FIELD OF THE INVENTION

The present invention relates in general to a dispenser comprising at least two parallel, hollow cylinders for supplying different mutually reactive components to a mixing device located downstream of said cylinders; a respective first piston move- able in each of the cylinders and displaceable by a piston rod connected to the re- spective piston; said pistons rods being interconnected for simultaneous dispensing of the components contained in the cylinders, when the piston rods and pistons are displaced in the cylinders towards a respective outlet therein; and a means for actuating the pistons rods to perform a forward stroke of the pistons in their respective cylinders for dispensing an amount of said reactive components to the mixing de- vice, said actuating means comprising a spring member adapted to act on the piston rods, and a manually operable brake member for controlling the force of the spring acting on the piston rods.

In particular, but not exclusively, the present invention relates to a dispenser of the above mentioned kind for supplying two mutually reactive sealant components, such as fibrinogen and thrombin, to a mixing device for applying an accurately mixed solution of such components to biological tissue, for example for effecting hemosta- sis or for any other type of therapeutic objective.

BACKGROUND OF THE INVENTION

Various types of dispensers for dispensing a two-component fluid mixture are known. E.g. WO 98/40115 discloses a dispenser of the kind mentioned in the introductory portion above. The dispenser has the shape of a pistol with a handle at the rear end thereof. A compression coil spring acts on the rear part of the piston rods via a slide, and one arm of a two-armed lever mounted at the handle acts as a brake on the slide to control the spring force exerted on the piston rods to thereby control the discharge of the fluid contents in the containers. Althougn mis pisioi-snapeα dispenser is mechanically simple, it may in some instances be awkward and difficult to manipulate accurately, when a precise application of the dispensed fluid mixture is required.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a dispenser, which is very compact in size and easy to manipulate carefully and accurately in narrow spaces. The dis- penser is preferably designed to be hand-held like a pencil with easy finger access to a brake-deactivating knob and may be disposable or refilled after emptying of the cylinder contents.

For this purpose the dispenser of the present invention, as described above by way of introduction, is characterized in that the actuating means comprises at least one rotatable member biased in a rotational direction by a torsion spring, and at least one flexible string attached, at a first end thereof, to the rotatable member so as to be wound thereon, and, at a second end thereof, to an element connected to the piston rods, wherein the manually operable brake means is arranged to normally act on the rotatable member to hold it still, but, when deactivated, adapted to release the rotatable member to thereby wind the string upon the rotatable member while simultaneously causing the pistons to perform a forward stroke for dispensing the reactive components to the mixing device.

Other features and structural details of the dispenser of the present invention will be set forth in the dependent claims and described in the following description under reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is a perspective view of a dispenser according to the present invention with a cover taken away;

Fig. 2 is a side view of a front portion of the dispenser in Fig. 1; and

Fig. 3 is a schematic side view of two cylinder compartments containing two mutually reactive fluid components in the dispenser of the present invention.

DESCRIPTION OF A PREFERRED EMBODIMENT

As shown in Fig. 1, a dispenser 10 of the present invention for dispensing two mutually reactive components, such as fibrinogen and thrombin to be mixed for creating a sealant for medical use, comprises an oblong housing 12 for receiving therein two parallel cylinders 14, 16 containing the two reactive fluid components. A first, rear piston 18, 20 is moveable forwardly in its respective cylinder 14, 16 from an initial rear position (Fig. 3), in which the cylinders 14, 16 are fully filled, by means of a respective piston rod 22, 24 extending rearwardly a distance corresponding at least to the intended maximal forward stroke of the pistons 18, 20 in the cylinders 14, 16. The piston rods 22, 24 are interconnected by a plate member 26 at a rear end thereof so as to be able of performing a simultaneous forward displacement of the pistons 18, 20 in the cylinders to thereby simultaneously discharge the two fluid components through respective outlet channels 28, 30 extending through a common frontal hub portion 32. A mixing appliance 33, for example of the kind described in SE-A-0100091-8, may be detachably mounted to the hub portion 32, as shown in Fig. 1.

As shown in Fig. 3, a forward piston 34, 36 is, in an initial rear position thereof in the respective cylinder, blocking the outlet channels 28, 30 for sealing the content in the cylinders before the initial use. Upon an initial forward displacement of the first, rear pistons 18, 20 in the cylinders the forward sealing pistons 3- , DO win oe moveα to a forward position in which they allow for a free fluid communication between the outlet channels 28, 30 and the interior of the cylinders 14, 16 via a bypass 28a and 30a.

Furthermore, the dispenser 10 of the present invention has a new type of actuating device for simultaneously displacing the pistons 18, 20 in their respective cylinders 14, 16. The actuating device comprises a rotatable drum 38 journalled for rotation about an axis transverse to the longitudinal extension of the dispenser 10 at a front portion of the housing 12. The drum 38 is biased by a torsion spring, schematically indicated at 40 in Fig. 2, so as to be capable of winding up at least one cord or string 42, 44 connected to the plate member 26 at the rear end of the piston rods 22, 24 of the respective cylinder 14, 16. A brake shoe 46 is normally frictionally engaging the drum 38 for preventing rotation thereof by means of a compression spring 48 biasing the shoe 46. The brake shoe 46 may be disengaged from the drum 38 by depressing a push rod 50 against the action of the spring 48 thereby allowing the torsion spring 40 to rotate the drum 38 for winding up the cords 42, 44 thereon and hence causing the first pistons 18, 20 to perform a forward movement in the cylinders 14, 16 for dispensing a desired amount of the respective reactive fluid components to the mixing appliance 33. As described above, the initial displacement of the first pistons 18, 20 will first cause the forward pistons 34, 36 to move from a sealing position to a forward position in which they open up the fluid communication between the outlet channels 28, 30 and the interior of the cylinders 14, 16 via the bypasses 28a, 30a.

The above-described dispenser 10 is structurally simple and compact and is easy to manipulate for accurate application of a mixed composition to an object owing to the fact that the dispenser may be hand-held in the vicinity of the outlet end thereof while at the same time controlling the discharge of the composition by depressing the push rod 50 with e.g. the thumb.

Claims (6)

1. A dispenser comprising: at least two parallel, hollow cylinders (14, 16) for supplying different mutually reactive components to a mixing device (33) located downstream of said cylinders; a respective first piston (18, 20) moveable in each of the cylinders (14, 16) and displaceable by a piston rod (22, 24) connected to the respective piston (18, 20); said pistons rods (22, 24) being interconnected for simultaneous dispensing of the components contained in the cylinders (14, 16), when the piston rods and pistons are displaced in the cylinders towards a respective outlet (28, 30) therein; and a means for actuating the pistons rods (22, 24) to perform a forward stroke of the pistons (18, 20) in their respective cylinders (14, 16) for dispensing an amount of said reactive components to the mixing device (33), said actuating means comprising a spring member adapted to act on the piston rods (22, 24), and a manually operable brake member for controlling the force of the spring acting on the piston rods, characterized in that said actuating means further comprises: at least one rotatable member (38) biased in a rotational direction by a torsion spring (40), and at least one flexible string (42, 44) attached, at a first end thereof, to the rotatable member (38) so as to be wound thereon, and at a second end thereof to an element (26) connected to the piston rods (22, 24), wherein the manually operable brake member (46, 48, 50) is arranged to normally act on the rotatable member (38) to hold it still, but, when deactivated, adapted to release the rotatable member (38) to thereby wind the string (42, 44) upon the rotatable member(38) while simultaneously causing the pistons (18, 20) to perform a forward stroke for dispensing the reactive components to the mixing device (33).

2. The dispenser according to claim 1, characterized in thai me DΓOUC πic uci +υ, 48, 50) and the rotatable member (38) are located in the vicinity of a forward end of the cylinders (14, 16), and that the rotatable member (38) is journalled so as to be able to rotate about an axis transverse to a longitudinal extension of the cylin- ders.

3. The dispenser according to claim 2, characterized in that the brake member comprises a brake shoe (46) biased by a spring (48) to normally frictionally engage the rotatable member (38) to a locked position, said brake shoe (46) being moveable against the action of said spring (48) by means of a rod (50) provided with a push button so as to release the rotatable member (38) and allowing it to rotate and perform a pulling action on the piston rods (22, 24) by means of the string (42, 44).

4. The dispenser according to any one of claims 1- 3, characterized in that the cyl- inders (14, 16) and the piston rods (22, 24) protruding from a rear end of the cylinders are accommodated in a common oblong housing (12).

5. The dispenser according to any one of claims 1-4, characterized in that each cylinder (14, 16), at a forward end thereof, houses a second piston (34, 36), which in a fully filled state of the respective cylinder seals the outlet (28, 30) thereof, and which upon an initial displacement of the respective first piston (18, 20) opens a bypass channel (28a, 30a) thereby bringing the interior of the cylinder (14, 16) into fluid communication with said outlet (28, 30).

6. The dispenser according to claims 4 or 5, characterized in that the outlets (28,

30) of the cylinders (14, 16) extend through a common hub (32) at the front end of the housing (12).