HK1185594A1 - Mixing and dispensing container - Google Patents

Abstract

The invention provides a container (10) which is used for mixing and distributing materials. The mixing and distributing container comprises a main chamber (17), a distributing nozzle (26), a liquid storage appliance (16) and an appliance body (12) of a plunger (18). The liquid storage appliance (16) is provided with a front portion, and the front portion is separated when the plunger (18) conducts hydraulic pressure on the front portion after being arranged so as to enable the plunger (18) to traverse the whole length of the appliance body (12). Therefore, the loading of materials in the main chamber (17) is enabled to be completely distributed into the distributing nozzle (26) through a fragile wall (22). The container (10) is provided with a compression area. The container is provided with a step area (50) to provide mobile limited resistance for low-adhesiveness materials. The risk that the low-adhesiveness materials are extruded in an uncontrolled mode is reduced.

Description

Mixing and dispensing container

Technical Field

The present invention relates to a mixing and dispensing container.

Background

US6386872 discloses a package for mixing a liquid component and a powdered component of a dental restorative material. In the initial state, the liquid component and the powder component are kept separate in the package. During mixing, a plunger 3 provided in a storage chamber 2a for holding a liquid component is pushed, the plunger including a forwardly projecting member 3a for piercing a slit forming portion 2c of a partition wall 2 for dividing the liquid component and the powdery component. The partition wall 2 is provided with a notch 2e to form the clearance hole forming portion 2 c.

Further, the package in said patent document also comprises an outlet nozzle 4 through which the plunger can be pushed towards the distal end of the package together with the partition wall 2, so that the dental restorative material is injected. To achieve injection, the partition wall 1c must also be pierced by said member 3 a. In this patent, the liquid composition remains intact during the squeezing process, and therefore, the user needs additional force to push the plunger to cause the liquid composition to flow through the entire package, and also needs additional force to push the member 3a to break through the partition wall 1c when the liquid is collected at the distal end of the package.

Disclosure of Invention

According to one aspect of the invention, there is provided a dental container for mixing and dispensing components of a dental mixture, having a main chamber, a dispensing nozzle, a liquid receptacle and a plunger, wherein the container comprises a body having a proximal end and a distal end, the main chamber being located near the distal end of the body, the main chamber having a frangible and seal-forming distal wall, and the dispensing nozzle being mounted at the distal end of the main chamber, the liquid receptacle being mounted inside the proximal end of the body, and the plunger being mounted in a sealed manner inside the liquid receptacle, the liquid receptacle having an inner transverse wall containing a weakened portion, and wherein the plunger has a non-projecting front face, the liquid receptacle containing a liquid and the main chamber containing a powder, the arrangement being such that, in use, pressure can be applied to the plunger to raise the liquid pressure by means of the liquid on the inner transverse wall to hydraulically damage the weakened portion resulting in the liquid entering the main chamber, and wherein a front portion of the liquid receptacle is arranged to be disengaged from a remaining portion of the liquid receptacle by further depression of the plunger to enable the plunger and the disengaged portion of the liquid receptacle to traverse the entire length of the main chamber to cause the distal wall to break by application of hydraulic pressure on the distal wall of the main chamber to cause the mixed dental material to be dispensed into the dispensing nozzle, and wherein the main chamber has a compression zone to provide resistance to movement of the disengaged portion of the liquid receptacle.

Drawings

The invention will now be described, by way of example, with reference to the accompanying drawings, in which:

FIG. 1 is a longitudinal sectional view of a container according to the present invention in an initial state;

FIG. 2 is a longitudinal cross-sectional view of the container of FIG. 1 in a partially activated state;

FIG. 3 is a longitudinal cross-sectional view of the container of FIG. 1 in a further partially activated state;

FIG. 4 is a longitudinal cross-sectional view of the container of FIG. 1 in a still further partially activated state;

FIG. 5 is a longitudinal cross-sectional view of the container of FIG. 1 in a fully activated condition;

FIG. 6 is a longitudinal cross-section of the body of the container of FIG. 1; and

fig. 7 is a perspective sectional view of the body shown in fig. 6.

Detailed Description

With reference to fig. 1 to 5, a container specifically contemplated for dental material dispensing is shown, wherein a front portion of the liquid receptacle is detached from the liquid receptacle.

Referring to fig. 1, a dental container 10 is shown in an initial open or storage state. The dental container 10 includes a body 12 having an inner surface 11 and being generally cylindrical in cross-section. Inside the body 12 there is a liquid receptacle 14 open at one end, which in use is intended to contain a liquid (not shown). The receptacle 14 is sealed by a plunger 18 (e.g., a sealing device on an outer surface 19 of the plunger 18 or on an inner surface 15 of the liquid receptacle 14). The plunger 18 is located in the open end of the receptacle 14 as shown and has a forward direction 41.

The body 12 contains a main chamber 17 which is used to hold an appropriate amount of powder (not shown) in use. The body 12 is sealed at the distal end 13 by a frangible membrane 22, the frangible membrane 22 being attached to the body 12 (e.g., at an annular inwardly extending flange 23 by any convenient means such as an adhesive). The distal end 13 of the body 12 is opposed to the proximal end 13a thereof. The body 12 has attached to it an end cap 24 connected to a nozzle 26 for dispensing material. The cap 24 is connected to the body 12 by means of a circumferential flange 28 having an inwardly extending annular rib 30 at its end remote from the nozzle 26. In the body 12, the ribs 30 engage with circumferential recesses 32.

A liquid tight seal (not shown) is preferably provided between the receptacle 14 and the plunger 18. The seal includes an annular rib that extends outwardly from the receptacle 14 to the plunger 18 and vice versa.

Further, the body 12 has an outwardly opening circumferential groove 34 near the plunger 18. The recess 34 is for engagement with a dispensing device (not shown) in use.

Further, the liquid receptacle 14 has a side wall 37 and an inner wall 36 with a central weakened portion 38. The central weakened portion 38 is substantially thinner than the remainder of the inner wall 36 of the liquid receptacle 14. In the state shown in fig. 1, the inner wall 36 is spaced from the front face 41 of the plunger 18.

Referring to FIG. 2, the container 10 is shown in the activated position. This activated position is achieved by pushing on the plunger 18, which pushing action causes the plunger 18 to move so that its inner end contacts the inner wall 36. This causes the liquid to move so that the weakened portion 38 of the inner wall 36 is damaged by the hydraulic pressure applied thereto by the liquid. The liquid is then pushed into the main chamber 17 of the body 12 into contact with the powder in the chamber 17. The container 10 may then be placed into a known vibratory mixing apparatus. So that the liquid and the powder mix and thereby form a paste in the chamber 17.

Referring to fig. 3, the container 10 is shown after the plunger 18 has been depressed and the liquid and powder have mixed to form a paste. The main chamber 17 of the body 12 now contains the paste. The front portion of the liquid reservoir 14 including its inner wall 36 has been detached from the rest of the liquid reservoir 14. This is due to the force transmitted from the plunger 18 to the front of the liquid reservoir 14 during dispensing of the paste with the dispensing apparatus. The remainder of the fluid receptacle 14 is held in place by means of an outwardly projecting annular step 40 on the fluid receptacle 14 engaging an annular recess 42 (see fig. 3) in the inner surface 11 of the body 12.

As shown in fig. 4, the plunger 18 pushes the front of the liquid reservoir 14 along the main chamber 17, wherein the front of the liquid reservoir 14 acts as a seal and prevents the paste from moving backwards. Means, such as slots, in the inner wall 11 of the body may be provided to act as evacuation means for entrained air escaping from the powder. The entrained air may be discharged into the recess formed by the separation of the front of the liquid reservoir 14. The slots may take the form of a plurality of elongated, generally parallel slots 46 (visible in fig. 6 or 7) or other forms.

As can be seen in fig. 1 to 5, the inner surface of the body 12 of the container 10 has an internal step 62 such that the proximal end 13a of the body 12 is larger in size than the distal end 13.

Further, the side wall 37 of the receptacle has an open-sided annular recess 64 adjacent the inner wall 36. The recess 64 engages the step 62 from the beginning (as shown in fig. 1).

It can be seen that the arrangement of the recess 64 and the step 62 enables the receptacle 14 to have a thin section 66 adjacent the inner wall 36. Thus, upon application of force to the plunger 18 (as described above), the inner wall 36 disengages from the receptacle 14 at the thin section 66 (as shown in fig. 3). This is because section 66 is relatively weak compared to inner wall 36. Furthermore, since the inner diameter of the distal end 13 of the main chamber 17 is smaller than the inner diameter of the proximal end portion 13a, all of the force applied to the plunger 18 is concentrated at the step 62 and the thin section 66 and therefore the inner wall 36 disengages in use as described above.

Referring to fig. 5, the container 10 is shown with all of the paste substantially dispensed. The front of the liquid receptacle 14 has been moved forward by the plunger 18 until it approaches the flange 23 of the body 12. When the plunger 18 is moved forward, the hydraulic pressure on the paste causes the membrane 22 to burst, which allows fluid transfer between the main chamber 17 and the nozzle 26 and subsequent dispensing of the paste to the desired location.

It can be seen that the inner surface 11 has a compressed region comprising a stepped region 50 of reduced cross-sectional dimension in which there is provided limited resistance to movement of the front disengagement section of the liquid receptacle 14. The results show that, in particular, by using a low-viscosity material, the limited resistance provided by the step 50 reduces the risk of uncontrolled extrusion of the low-viscosity material.

The stepped region 50 slows the advancement of the front portion of the liquid receptacle and the extrusion rate of the material correspondingly slows down. The proximal face of the stepped region 50 is preferably tapered to provide a smooth transition from the main portion of the inner surface 11 and the stepped region.

In use, a user places the container 10 into a suitable dispensing device (not shown) by any convenient means 34 to allow pressure to be applied to the plunger 18. The pressure applied to the plunger 18 via the movement of the liquid 16 causes the hydraulic pressure to rise relative to the weakened portion 38. Once the hydraulic pressure reaches the critical point, the weakened portion 38 breaks and then the liquid 16 enters the main chamber 17. The plunger 18 is then moved forward again by the dispensing device. This brings the front face 41 of the plunger 18 into intimate contact adjacent the rear face of the inner wall 36.

Main chamber 17 now contains liquid 16 and powder 20. The user then places the dental applicator into a suitable mixing device, such as a vibratory mixer. The agitation caused by the mixing device causes the liquid and powder to mix and combine to form a paste.

After mixing, further forward movement of the plunger 18 causes an increasing pressure to be applied against the liquid reservoir 14. Once sufficient force is applied, the front of the liquid receptacle 14 disengages as shown in fig. 3. This leaves the side wall 37 of the liquid receptacle 14 substantially intact.

As the plunger 18 moves forward, a slot 46 (see fig. 6 and 7) in the inner surface 11 of the main chamber 17 may allow any air trapped inside the container or mixing material to vent into the recess formed by the separation of the front of the liquid reservoir 14 from the side wall 37. Further, the mixing process may not result in complete mixing of all of the powder components, but rather leaves some residual powder, for example, in the area between the front of the liquid receptacle 14 and the inner wall 11 of the body 12. This may actually cause problems as the area treated by the dental material is contaminated by residual powder components. As the plunger 18 and inner wall 36 move forward, a recess is formed behind the inner wall 36. Powder particles with an unmixed remainder can escape around the front and into the recess, thus reducing the risk of contamination of or exposing the user to these particles.

Further forward movement of the plunger 18 will cause the plunger 18 to move toward the distal end of the body 12, as shown in fig. 5. This will result in an increase in fluid pressure relative to frangible membrane 22. Once the hydraulic pressure reaches a critical value, the membrane 22 will burst. Thus, the paste 28 is placed in fluid communication with the nozzle 26. Still further, forward movement of the plunger 18 will cause the paste to pass through the nozzle 26 and then eventually dispense. However, as mentioned above, the presence of the step 50 provides a compression zone which provides a degree of resistance to further movement of the front portion of the receptacle 14 from the position shown in figure 4 to the position shown in figure 5.

Modifications and variations as would be apparent to a skilled addressee are deemed to be within the scope of the present invention.

Claims (8)

1. Dental container for mixing and dispensing components of a dental mixture, having a main chamber, a dispensing nozzle, a liquid receptacle and a plunger, characterised in that the container comprises a body having a proximal end and a distal end, the main chamber being located near the distal end of the body, the main chamber having a frangible and seal-forming distal wall, and the dispensing nozzle being mounted at the distal end of the body, the liquid receptacle being mounted inside the proximal end of the body, and the plunger being mounted in a sealed manner inside the liquid receptacle, the liquid receptacle having an inner transverse wall containing a weakened portion, and wherein the plunger has a front face without projections, the liquid receptacle containing a liquid and the main chamber containing a powder, such that, in use, pressure can be applied to the plunger to raise the pressure of the liquid acting on the inner transverse wall, thereby hydraulically damaging the weakened portion resulting in the liquid entering the main chamber, and upon further depression of the plunger, a front portion of the liquid receptacle disengages from a remaining portion of the liquid receptacle so that the plunger and the disengaged portion of the liquid receptacle can traverse the entire length of the main chamber, the distal wall being caused to break by application of hydraulic pressure on the distal wall of the main chamber resulting in dispensing of the mixed dental material into the dispensing nozzle, and wherein the main chamber has a compression region to provide resistance to movement of the disengaged portion of the liquid receptacle, the compression region having a stepped region with a reduced cross-sectional dimension so as to provide limited resistance to movement of the front portion of the liquid receptacle.

2. The container of claim 1, wherein said distal end of said body has an annular end cap mounted thereto, said end cap having an aperture, and a frangible membrane forming said frangible distal end wall is mounted between said distal end of said body and said end cap.

3. A container according to claim 1 or 2, wherein the liquid receptacle has an outwardly open end and a closed inner end, the plunger being mounted in the open end of the liquid receptacle.

4. A container according to claim 3, characterised in that the liquid receptacle has a frangible portion arranged to break when pressure is applied by the plunger.

5. A container according to claim 4, characterised in that the receptacle has a side wall and an inner end wall, the side wall having a frangible portion arranged to fail when pressure is applied by the plunger.

6. A container according to claim 5, characterised in that the main chamber contains a step on its inner surface and the liquid receptacle has an annular recess which engages with the step from the outset, the annular recess forming the frangible portion such that in use once the plunger is pushed, the plunger engages with the step in the inner surface and the front of the liquid receptacle disengages at the step.

7. A container according to claim 3, characterised in that the body has an inwardly concave seat at the proximal end thereof arranged to engage with an outwardly convex portion on the liquid receptacle so that a rear portion of the liquid receptacle remains fixed relative to the body after the front portion has been disengaged.

8. A container according to claim 1, wherein the stepped region tapers at the distal end away from the body so as to provide a relatively smooth transition from a major portion of the inner surface of the main chamber and the stepped region.