APPARATUS AND METHODS FOR STORING AND MIXING SEPARATE SUBSTANCES

Abstract

A storage and mixing device includes a mixing compartment, two pistons that each extend from the mixing compartment and end in a displacement section, each piston defining a passageway having a first opening communicating with the mixing compartment and a second opening communicating with an inlet at the displacement section, and a housing having two piston guides and a cartridge compartment connected to the piston guide, each piston guide slidably receiving one of the pistons, and each cartridge compartment receiving a removable cartridge that includes a cavity for containing separate substances and an opening sealed by a cartridge seal. The displacement section of each piston includes a piercing member for piercing the cartridge seal of the cartridge arranged in the corresponding cartridge compartment, such that the displacement section enters the cartridge cavity and displaces the contained substance into the mixing compartment via the inlet and the passageway.

Claims

1. A storage and mixing device for separate substances comprising: a mixing compartments; at least two pistons, each piston of the at least two pistons extending from the mixing compartment and ending in a displacement section, and defining a passageway having a first opening that communicates with the mixing compartment and a second opening that communicates with an inlet at the displacement section; and a housing having at least two piston guides and a cartridge compartment of at least two cartridge compartments connected to each piston guide of the piston guides, each piston guide of the piston guides slidably receiving a piston of the at least two pistons, and each cartridge compartment of at least two cartridge compartments configured to receive a removable cartridge of at least two removable cartridges, each removable cartridge comprising a cavity containing one of the separate substances and an opening sealed by a cartridge seal, the displacement section of each piston of the at least two pistons further comprises a piercing member configured to pierce the cartridge seal of the removable cartridge of the at least two removable cartridges arranged in a corresponding cartridge compartment, such that the displacement section of each piston of the at least two pistons is capable of entering the cavity of the removable cartridge of at least two removable cartridges arranged in the corresponding cartridge compartment and displace the contained substance into the mixing compartment via the inlet and the passageway.

2. The storage and mixing device of claim 1, further comprising the at least two removable cartridges received in the cartridge compartments, the cavity of each cartridge containing the substance for forming a mixture.

3. The storage and mixing device of claim 2, wherein, for each piston and cartridge, the volume of the passageway of the piston is substantially smaller than a storage capacity of the cavity.

4. The storage and mixing device of claim 1, wherein the at least two pistons extend in parallel from the mixing compartment.

5. A storage and mixing device for separate substances comprising: a piston having a displacement section arranged at one end, the piston defining a mixing compartment in communication with an inlet at the displacement section, and a housing having a piston guide and a cartridge compartment connected to the piston guide, the piston guide slidably receiving the piston in a sliding direction, and the cartridge compartment configured to receive a removable cartridge comprising a cavity containing at least two separate substances and an opening sealed by a cartridge seal, the cavity comprising at least one inner membrane partitioning the cavity into at least two sealed partitions arranged adjacently in the sliding direction, each sealed partition of the at least two sealed partitions storing one of the separate substances, and the displacement section of the piston further comprising a piercing member configured to first pierce the cartridge seal and then the at least one inner membrane of the cartridge, such that the displacement tip is capable of entering the cartridge cavity and displace the contained substances into the mixing compartment (26) via the inlet of the displacement section.

6. The storage and mixing device of claim 5 further comprising the cartridge received in the cartridge compartment, the cavity of the cartridge comprising the at least two sealed partitions, each sealed partition of the at least two sealed partitions containing a substance of the separate substances for forming a mixture.

7. The storage and mixing device of claim 6 wherein, for the piston and cartridge, an end face of the displacement section of the piston matches an inner surface of the cartridge cavity arranged opposite to the opening in the cartridge.

8. The storage and mixing device of claim 6 wherein, for the piston and cartridge, a width of the piston guide and a width of the opening in the cartridge stored in the cartridge compartment are substantially equal.

9. The storage and mixing device of claim 5, wherein the piston guide forms a seal with an outer surface of the piston slidably received in the piston guide by a sealing member.

10. The storage and mixing device of claim 5, wherein the piercing member is a tip that does not coincide with the inlet of the displacement section of the piston.

11. The storage and mixing device of claim 5, wherein the cartridge compartment comprises at least one retaining members configured to engage an outer surface of the cartridge.

12. The storage and mixing device of claim 1, wherein the housing comprises a locking member that engages an outer surface of the mixing compartment.

13. The storage and mixing device of claim 1 wherein the mixing compartment comprises a removable closure cap.

14. A mold comprising: a first mold segment and a second mold segment that abut to form a mold cavity, at least part of the mold cavity corresponds in shape to the housing or the piston of the storage and mixing device according to claim 1.

15. A method of mixing a first and a second substance, using the storage and mixing device of claim 1, the method comprising: loading a respective cartridge containing at least one substance in each of the cartridge compartments; applying pressure to a section of the mixing compartment remote from the displacement section of each piston to effect movement of each piston relative to the housing and in a first direction; piercing the cartridge seal of the respective cartridge with the piercing member of the displacement section of each piston; continuing to effect movement of each piston in the first direction until the end face of the displacement section of each piston meets an inner surface of the cavity of the respective cartridge arranged opposite to the opening such as to effect movement of the substance stored in the respective cartridge in a second direction opposite the first direction and into the mixing compartment via the inlet of the displacement section.

16. The storage and mixing device of claim 1, wherein the at least one retaining members is a collar engaging a peripheral surface of the cartridge opposite from the opening of the cartridge or a projection arranged adjacent the piston guide connected to the cartridge compartment and engaging a corresponding notch at an outer surface of the cartridge.

17. The method of claim 15, wherein the first and second substances are mixed to create a medical, dental, pharmaceutical, cosmetic, adhesive or veterinary preparation.

18. The storage and mixing device of claim 2 wherein, for each piston of the at least two pistons and removable cartridge of the at least two removable cartridges arranged in a corresponding cartridge compartment, an end face of the displacement section of the piston matches an inner surface of the cavity arranged opposite to the opening in the removable cartridge.

19. The storage and mixing device of claim 2 wherein, for each piston of the at least two pistons and removable cartridge of the at least two removable cartridges arranged in a corresponding cartridge compartment, a width of the piston guide of the piston guides slidably receiving the piston and a width of the opening in the cartridge are substantially equal.

20. The storage and mixing device of claim 1, wherein each piston of the piston guides forms a seal with an outer surface of the piston of the at least two pistons slidably received in the piston guide by a sealing member.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Referring now to the attached drawings which form a part of this original disclosure.

[0030] FIGS. 1A and 1B show an embodiment of a device in accordance with the first aspect of the present invention in a storage state;

[0031] FIGS. 2A and 2B show the embodiment of FIGS. 1A and 1B in a mixing state;

[0032] FIGS. 3A and 3B show the cartridge of FIG. 1A through FIG. 2B;

[0033] FIGS. 4A and 4B show an embodiment of a device in accordance with the second aspect of the present invention in a storage state;

[0034] FIGS. 5A and 5B show the embodiment of FIGS. 4A and 4B in a mixing state; and

[0035] FIGS. 6A and 6B show the cartridge of FIGS. 4A through 5B.

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0036] Referring to the figures, wherein like numerals indicate corresponding parts throughout the several views and aspects of the invention, a storage and mixing device 20 for separate substances (hereinafter ‘device’) comprises a housing 22 for storing one or more cartridges 24, each of which contains at least one substance. The substances can be fluids, gels or the like and are mixed together to form a mixture such as medical, dental, pharmaceutical, cosmetic, adhesive or veterinary preparation. Each substance is dispensed into a mixing compartment 26 by a piston 28, in particular, displaced into the mixing compartment 26 by a displacement section 30 formed at the end of the piston 28. The housing 22 and the one or more pistons 28 can be made of a material comprising polypropylene or polyethylene.

[0037] Turning to the embodiment shown in FIGS. 1A through 2B, the device 20 comprises two sealed cartridges 24 and a piston 28 corresponding to each cartridge 24 to dispense a stored substance into a mixing compartment 26. The mixing compartment 26 is connected to the pistons 28. In the storage state of the device 20, shown in FIGS. 1A and 1B, each cartridge 24 is loaded into a corresponding cartridge compartment 32 of the device housing 22. In other words, the substances are kept sealed and separate from one another and have not yet been mixed. Accordingly, the device makes it possible to store the substances for a longer amount of time than the mixture itself could be stored.

[0038] The cartridges 24, which are show in detail in FIGS. 3A and 3B, are generally installed during the manufacture of the device 20 so that a fully assembled device 20 can be delivered. However, it is also conceivable for the user to load the cartridges 24 required to form the desired mixture. A material can be selected for cartridge 24 that is most compatible with the stored substance, such as cyclic olefin copolymer (COC), so that the storage life of the substance is not shortened by a reaction to the cartridge material. A cartridge cavity 50 for containing the substance can be created, for example, by injection molding, and then filled with the substance. A cartridge seal 36 for sealing the cartridge cavity 50 can then be welded on.

[0039] The two pistons 28 extend in parallel from the mixing compartment 26 and end in a displacement section 30 for displacing the substance stored in the cartridge 24. The displacement section 30 includes a piercing means or member 34 for piercing the cartridge seal 36 and an inlet 38 into which the substance can be displaced. The extent of the piston 28 also defines a passageway 40 that connects the inlet 38 of the displacement section 30 to the mixing compartment 26. In the storage state of the device 20, the displacement sections 30 of the pistons 28 are each slidably supported in a piston guide 42 that is arranged adjacent to and communicates with a respective cartridge compartment 32.

[0040] In the storage state, the piercing member 34 of each displacement section 30 may rest on or slightly above the cartridge seal 36 of the corresponding cartridge 24. To prevent the pistons 28 and their respective displacement sections 30 from moving toward the cartridges 24 and piercing the cartridge seals 36, the device housing 22 comprises a locking member 44 that engages an outer corner of the mixing compartment 26.

[0041] To transition from the storage to the mixing state, pressure is applied to the mixing compartment 26, for example, at a closure cap 46. Once the locking force of the locking member has been overcome, the parallel pistons 28 begin to slide in unison along the piston guides 42, i.e. in a first direction X relative to the housing 22, and toward their respective cartridges 24. In this context, friction and/or adhesion between the pistons 28 and the piston guides 42 can be reduced by manufacturing the device housing 22 and the pistons 28 from different materials, such as polypropylene and polyethylene respectively.

[0042] In the illustrated embodiment, the piercing member 34 of each displacement section 30 is formed as a sharp tip which pierces the cartridge seal 36 that seals an opening of the cartridge cavity 50 for receiving the stored substance. However, other configurations of the piercing member, such as a sharp annular edge, are also possible. By forming the inlet 38 of the displacement section 30 adjacent to, but not coinciding with, the piercing tip 34, the piercing tip 34 is made particularly sharp. To make piercing the cartridge seals 36 easier, each cartridge compartment 32 also comprises two retaining members 52 to engage and stabilize the cartridge. A first retaining member 52 is a formed by a notch adjacent to the piston guide 42 that engages an outer cartridge surface. A second retaining member 52 is formed by a collar that encircles a base 54 of the cartridge 24 (FIGS. 3A and 3B).

[0043] Once the cartridge seal 36 has been pierced, the piston guide 42 continues to guide the piston 28 toward the cartridge compartment 32 in the first direction X, so that the displacement section 30 of the piston 28 enters a cartridge cavity 50 (FIG. 3B) and displaces the substance stored in the cavity 50 into the inlet 38 of the displacement section 30 in a second direction Y that is opposite the first direction X.

[0044] As the piston 28 further enters the cartridge cavity 50, an increasing amount of the substance is displaced into the passageway 40 of the piston 28 until the substance reaches the mixing compartment 26. In order to ensure that the displaced substance flows into the inlet 38 as opposed to through a gap between the piston 28 and the piston guide 42, the piston guide 42 comprises a sealing member 56 that forms a seal with an outer surface of the piston 28. In the illustrated embodiment, the sealing member 56 is formed by a projection provided at an inner wall of the piston guide 42. Alternatively or additionally, a sufficient sealing effect may be provided by a sufficiently elastic cartridge seal 36 that hugs the outer surface of the piston 28 after being pierced.

[0045] When both substances have been displaced into the mixing compartment 26, the substances can mix together to form the desired mixture, as shown in the final, ready-to-use state of FIGS. 2A and 2B. In this state, the closure cap 46 can be removed so that the prepared mixture can be taken from the mixing compartment 26 using, for example, a separate applicator 66. Since it is difficult to access the mixture remaining in the inlets 38 and passageways 40 using the applicator 66, it is desirable to configure the inlets 38 and passageways 40 to be as small as possible, so that as much of the mixture is displaced to the mixing compartment 26 as possible. This is the case when a volume of the passageway 40 is substantially smaller than the storage capacity of the cartridge cavity 50, with the storage capacity, i.e. the volume of the cartridge cavity 50, ranging for example from 0.3 to 10 ml. For a piston 28 having a particular length, this translates to a passageway 40 that is substantially narrower than the piston 28.

[0046] In the illustrated embodiment, a thorough displacement or removal of each substance into the mixing compartment 26, is provided when the displacement section 30 of the piston 28 occupies the entire volume of the cartridge cavity 50 in the mixed state. One reason for this is that an end face 57 of the displacement section 30 that faces a bottom surface 58 of the cartridge cavity 50 is configured to mate with the cartridge cavity 50.

[0047] A further reason is that a maximum width of the displacement section 30 corresponds substantially to a maximum inner width wi of the cartridge cavity 50 (FIG. 3B). Furthermore, the widths of the piston 28, piston guide 42 and cartridge opening are substantially equal. As the cartridge compartment 32 is configured to accommodate the outer width of the cartridge, the housing 22 forms an annular shoulder 60 between each cartridge compartment 32 and adjacent piston guide 42. When the cartridge 24 is inserted into the cartridge compartment 32, the cartridge seal 36 is secured between the shoulder 60 and the remainder of the cartridge 24, making the cartridge seal 36 easier to pierce.

[0048] FIGS. 4A and 4B show a device 20 in accordance with a further aspect of the present invention that is described in terms of its differences to the device 20 shown in FIGS. 1A through 2B. In particular, the device 20 comprises a single piston 28 and single removable cartridge 24 that stores the substances in separate, sealed partitions 62 of the same cartridge 62.

[0049] Accordingly, a device housing 22 comprises one cartridge compartment 32 for receiving the sealed cartridge 24 and one piston guide 42 connected to the cartridge compartment 32. In addition to a cartridge seal 36 sealing an opening to a cartridge cavity 50, the cartridge 24 comprises one or more inner membranes 64 that partition the cartridge cavity 50 into two or more sealed partitions 62 (FIG. 6B). The inner membranes 64 are arranged in such a way that when the cartridge 24 is inserted into the cartridge compartment 32, the sealed partitions 62 are arranged serially, i.e. one after another, with respect to the piston guide 42.

[0050] In the device 20 of FIGS. 4A through 5B, the one piston 28 defines both a longitudinal mixing compartment 26 and a displacement section 30 for displacing the substances stored in the individual partitions of the cartridge. The displacement section 30 includes a piercing member 34 for piercing the cartridge seal 36 and inner membranes 64, as well as an inlet 38 that is connected to the mixing compartment 26 and displaces the substances stored in the cartridge into it. In contrast to the device of FIGS. 1A through 2B, the mixing compartment 26 is directly connected to the inlet 38 of the displacement section 30 as opposed to via a passageway.

[0051] The one piston 28 is slidably received in the one piston guide 42, which guides the displacement section 30 of the piston 28 toward the cartridge compartment 32. When the piston 28 is moved relative to the device housing 22, the piercing tip 34 of the displacement section 30 first makes contact with and pierces the cartridge seal 36 that seals an opening of the cartridge cavity 50. The piercing of the cartridge seal 36 allows the displacement section 30 to move into the first partition of the cartridge cavity 50 and displace the substance stored in the first partition into the mixing compartment 26 via the inlet 38 of the displacement section 30.

[0052] As the piston 28 continues to move relative to the housing 22, the piercing tip 34 of the displacement section 30 then makes contact with and pierces the at least one inner membrane 64. This enables the displacement section 30 to move into and displace the substance stored in the next partition of the cartridge cavity 50 into the mixing compartment 26. As the piston 28 moves further into the cartridge cavity 50, an increasing amount of the substances is displaced into the mixing compartment 26 until an end face 57 of the displacement section 30 reaches a bottom surface 58 of the cartridge cavity 50, as shown in FIGS. 5A and 5B.

[0053] As shown in FIGS. 6A and 6B, one way of forming the cartridge 24 with its multiple partitions 62 is to fill a first cartridge section 24a with a first substance and then seal the first cartridge section 24a with an inner membrane 64, thus forming a first partition 62a. Next, a second cartridge section 24b is welded onto the first cartridge section 24a and filled with a second substance. The second cartridge section 24b is then sealed with the cartridge seal 36 to form a second partition 62b. The combined cartridge sections 24a and 24b thus form the cartridge 24 as a whole, while the partitions 62a, 62b correspond to the cartridge cavity 50. In this context, the cartridge sections 24a, 24b can be made of a material comprising cyclic olefin copolymer (COC) and by injection molding. Although the inner membrane 64 and cartridge seal 36 are described as separate parts, it is appreciated that they can be made of the same type of material.