TECHNICAL FIELD

This invention relates to containers which include a closure relying at least in part on magnetic attraction between components of the container to remain in a closed configuration .

DESCRIPTION OF RELATED ART

Containers and packaging have customarily been provided with mechanical closures which rely on parts having an interfering fit to retain one part of the container closed against another part of the container. Magnets have been suggested as an alternative to mechanical closures in containers. In such proposed containers, magnetic closures have required the use of two magnets (attached to different parts of the container) or a magnet and a ferrous component (attached to different parts of the container) . However, such proposed containers are bulky and expensive and are not suitable for applications in which cost, small size and aesthetics are a concern. Therefore, there remains a need for a container which utilizes a magnetic closure that is inexpensive to produce, slim and aesthetically pleasing. SUMMARY

This invention relates to containers which include a closure relying at least in part on magnetic attraction between components of the container to remain in a closed configuration .

In general, in one aspect, the invention features a container comprising a top, a base and a magnet, in which the top is at least partially comprised of a plastic material intermixed with a passive magnetic material, and the magnet is attached to the base such that the magnet exerts a closing force on the top, tending to retain the top and base in a closed configuration. Alternatively, the base can be at least partially comprised of a plastic material intermixed with a passive magnetic material, and the magnet can be attached to the top, to achieve the same result.

BRIEF DESCRITION OF THE DRAWINGS

The above mentioned and other aspects, features and advantages can be more readily understood from the following detailed description with reference to the accompanying drawings, wherein:

Figures 1A and IB show partial cutaway views of a container in an open and closed configuration, respectively, according to an exemplary embodiment of the present invention;

Figure 2 is a partial cutaway view of a prior art container;

Figure 3 is a partial cutaway view of a container according to another exemplary embodiment of the present invention ;

Figure 4 is a partial cutaway view of a lipstick container according to yet another exemplary embodiment of the present invention; and

Figure 5 is a partial cutaway view of a pen container according to still another exemplary embodiment of the present invention .

DETAILED DESCRIPTION

Containers with magnetic closures are described herein, with reference to examples and exemplary embodiments . Specific terminology is employed in describing examples and exemplary embodiments. However, the disclosure of this patent specification is not intended to be limited to the specific terminology so selected and it is to be understood that each specific element includes all technical equivalents that operate in a similar manner.

Figures 1A and IB show partial cutaway views of a container 10 in an open and closed configuration, respectively, according to an exemplary embodiment of the present invention. In the example shown in Figures 1A and IB, a container 10 includes a base 12, a top 14 and a magnet 16. The base 12 extends along a main axis A between a closed bottom and an upper end, the upper end presenting an opening. The top 14 is intended to close the opening of the base 12, the dimensions of the top 12 being appropriate to come into contact with the upper end of the base 12 and to cover the opening. The top and base may be made from any of a wide range of materials. For example, materials for the top and base include thermoplastics, thermosetting polymers, glass, metal, wood, ceramics , etc . Materials for the magnet 16 include any material exhibiting a permanent magnetic field . For example, the magnet 16 may be a rare earth magnet (N35, N27, etc.), Al-Ni-Co, ferrite, Mn-Al, neodymium, neodymium-iron-boron, injectable magnet material (such as injectable ferrite or neodymium-iron-boron with a Nylon binder) or any ferromagnetic material imparted with a magnetic field.

In order for the container 10 to be held in a closed configuration as shown in Figure IB, the magnet 16 must be paired with a component at least partially comprised of a passive magnetic material to which it is attracted.

The expression "passive magnetic material" must be understood in relation with the meaning of "magnet". "Magnet" refers here to any element made in a material which generates a permanent magnetic field under normal conditions of use in the field of containers and packaging.

On the contrary, the expression "passive magnetic" refers here to the property of a material not to generate a permanent magnetic field in the absence of any magnetic field, i.e. the property to be passive, under normal conditions of use in the field of containers and packaging, but to be attracted by a magnet. It encompasses ferromagnetic properties.

In containers 20 proposed in the prior art such as the type shown in Figure 2, magnetic closures comprise two magnets 26A and 26B, each attached to different parts of the container 22 and 24, respectively. The magnets 26A and 26B are attracted to each other when brought into close proximity and provide the container parts 22 and 24 with a closure force. However, the prior art containers which use two separate magnets (or groups of magnets) require substantial bulkiness to accommodate the magnets and do not lend themselves to applications where size or aesthetics are important. In addition, the requirement of two or more magnets in the prior art containers add substantial cost - often comprising more than half of the total cost of the container.

The present invention represents a significant improvement over the prior art. By eliminating the requirement for two magnets, the present invention opens up a multitude of design possibilities because designers are no longer limited to sizes and shapes required to accommodate the use of two separate magnets.

In a container according to the present invention, only one magnet 16 is required for the container 10. As shown in the example of Figures 1A and IB, the magnet 16 is rigidly fixed to the top 14. Alternatively, the magnet may be fixed to the base 12. The magnet 16 may be fixed to the top 14 or base 12 by, for example, an adhesive, a mechanical interference or friction, heat-staking, etc. The magnet 16 shown in Figures 1A and IB is a ring type magnet with an aperture through its center. Alternatively, the magnet could be any shape or size accommodated by the container, or could be an array of two or more magnets.

Also, according to the present invention, and in the example shown in Figures 1A and IB, the base 12, or a portion thereof, is made of a material having a passive magnetic property, that is to say a material which does not induce a permanent magnetic field under normal conditions but which is attracted by a magnet. In other words, the material of the base 12, and thus the base 12 itself is attracted to the magnet 16. This feature of the invention is particularly beneficial because it provides the designer with a multitude of design options because the magnet can be located at any position on the top that enables the magnet to attract the base.

While conventional ferromagnetic materials may be used for the base 12 (or any container component to which the magnet is attracted) , such as steel alloys and the like, many container manufacturing methods such as injection molding are incompatible with such materials. Injection molding is a preferred manufactured process in the field of containers and packaging, considering cost, production rate, and the shape of the components to be manufactured. In one example, the base 12 (or any container component to which the magnet is attracted) may be made by injection molding and may include a passive magnetic material in which passive magnetic particles, or powder, are suspended in and intermixed with a non magnetic material, acting as a binder. For instance, the non magnetic material is a thermoplastic material, such as polypropylene (PP) , polyethylene terephtalate (PET) , polyvinylchloride (PVC) or any other polymer suitable for molding and / or injection. The passive magnetic particles can be for instance iron particles, ferrite particles, or passivated ferric oxide particles. Such mixtures were previously used for unrelated purposes, for example, to add weight to an injection molded component. However, the magnetic properties of such materials are not yet known to have been recognized or used in the context of containers, or magnetic closures for containers, in accordance with the present invention. One example of such a material is RTP 199 X 84145 Polypropylene High Gravity Compound (RTP Company, Winona, Minnesota) .

When the magnet 16, for instance rigidly fixed to the top 14, is close enough to the base 12, the particles are subjected to the magnetic field generated by the magnet 16 and get aligned according to the magnetic field lines. The base 12 is then attracted by the magnet 16, in order to secure the container in the closed configuration, wherein the top 14 and the base 12 are blocked relatively to each other, at least in translation. Complementary means for blocking the rotation, around the main axis A, of the top 14 relatively to the base 12 can be added. For instance, such means can be found in a non-circularly-symmetrical geometry of the top 14 and / or the base 12.

It has been found that the invention does not reduce the degree of magnetic attraction required for a reliable magnetic seal. In particular, the magnetic attraction remains sufficient and appropriate to maintain the container in the closed configuration unless a user exerts a manual effort in order to unsecure the top 14 and the base 12. The degree of attractive force between the magnet 16 and the opposing container component (the base 12 in the example shown in Figures 1A and IB) may, however, be adjusted according to the desired purpose of the container. The attractive force may be altered by, for example, the shape of the magnet, the shape of the opposing container component, the material composition of the magnet, the material composition of the opposing container component, etc. Further, the material composition of the opposing container component may be altered by, for example, varying the type or relative content of passive magnetic material used therein.

Moreover, the magnet, by definition, is magnetically oriented and comprises a north pole and a south pole. However, the base 12 made in passive magnetic material does not present any magnetic orientation, so that the base 12 is attracted by the magnet 16 in the top 14 independently from their respective orientation. Consequently, the conception and the assembly of the container are greatly simplified, as the magnet 16 does not need to respect any orientation to properly cooperate with the passive magnetic material and to provide the magnetic seal . Similarly, the base 12 can be molded by inj ection of the passive magnetic material without any condition on the localisation of the magnetic poles of the base. The magnetic poles of the base 12 appear under the magnetic field generated by the magnet 16, and are in consequence always naturally oriented to properly cooperate with the corresponding magnet 16.

The magnet 26 may be attached to a container component by any known means and may comprise, for example, one or more of a friction fit, an adhesive, an interference fit, etc. In one exemplary embodiment, shown in Figure 3, an annular magnet 26 is attached to a top 16 by an interference fit with a bead 30 formed in top 14. The magnet 16 is pushed past the bead 30 by an insertion tool, temporarily deforming the top 14 and/or the magnet 16. Once past the bead, the components are mechanically held together. Also shown in Figure 3 is an optional depth stop 32 formed in the top 14. A top may include one or more depth stops 32 which serve to locate the magnet securely within the inner periphery of the top 14. Such location may be important, for example, to a closure in which a lower edge 34 of the top is configured to precisely meet an upper edge 36 of the base 12. In such a configuration (an example of which is shown in Figures IB and 3) , a surface 38 of the magnet contacting the base 12, the lower edge 34 of the top 14 and the upper edge 36 of the base 12 must be in alignment when the container 10 is in a closed configuration. A slight gap between the top and base components when they are in a closed configuration may be introduced to allow for imperfect dimensional or assembly tolerances of the various components.

In addition, magnets typically attach together by a snap action as soon as the magnets come within attractive distance to each other. Accordingly, in the proposed prior art containers which use a magnet on each of the top and base, the top and base snap together when their respective magnets come within attractive distance. It has been found that, when one container component contains a magnet and the other container component is formed of a material presenting passive magnetic properties according to the present invention, the top and base components attach together in a smooth fashion. This smooth movement may be more pleasing to a user and may impart a higher quality to the container product.

It is defined a distal portion and a proximal portion of the top 14, relative to the base 12 when the container 10 is in the closed configuration, and a distal portion and a proximal portion of the base 12, relative to the top 14 when the container 10 is in the closed configuration. According to a first embodiment, the base 12 is made in the passive magnetic material, and the magnet 16 is rigidly fixed to the top 14.

In this first embodiment, the magnet 16 can be attached to the distal portion of the top 14 and be located nearer to the proximal portion of the base 12 than to the distal portion of the base 12 when the container 10 is in the closed configuration .

As a variant of the first embodiment, the magnet 16 can be attached to the proximal portion of the top 14 and be located nearer to the distal portion of the base 12 than to the proximal portion of the base 12 when the container 10 is in the closed configuration .

According to a second embodiment, the top 14 is made in the passive magnetic material, and the magnet 16 is rigidly fixed to the base 12.

In this second embodiment, the magnet 16 can be attached to the distal portion of the base 12 and be located nearer to the proximal portion of the top 14 than to the distal portion of the top 14 when the container 10 is in the closed configuration .

As a variant of the second embodiment, the magnet 16 can be attached to the proximal portion of the base 12 and can be located nearer to the distal portion of the top 14 than to the proximal portion of the top 14 when the container 10 is in the closed configuration.

The containers described herein have many applications, some of which are described more fully herein. For example, a container having a magnetic closure as described herein may be adapted for use with cosmetics packaging, writing implements, fluid containers such as perfume bottles, jewelry boxes, etc. In one exemplary embodiment, shown in Figure 4, a container 40 having a magnetic closure is adapted for packaging and dispensing a lipstick product 42. As in conventional lipstick containers, a product movement mechanism is included to move the lipstick product 42 axially in and out of the base 12. One skilled in the art will recognize that any product movement mechanism adapted for lipstick containers may be implemented in the container proposed herein. In the example shown in Figure 4, the base 12 may comprise several components 12A-12E which form a product movement mechanism and may be configured to move relative to one another to move the lipstick product 42 in an axial direction, along the main axis A, away from component 12A to an extended application position. The movement of the lipstick product 42 may be effectuated by a user twisting component 12A relative to a shell component 12B, for example. The product 42 is held in a cup 12E. The cup 12E is slidingly guided by an inner component 12D, and cooperates through an helical link with a spiral component 12C. The spiral component 12C is rotated by the actuation of the user twisting component 12A around the main axis A, forcing the cup 12E to slide along the main axis A, the inner component 12D guiding the cup 12E. Optionally, a weight 12F may be added to the base 12 to enhance a user's perception of the lipstick container's value or quality.

In the exemplary lipstick container 40 shown in Figure

4, the magnet 16 is attached in the manner disclosed above to the inner surface of the top 14. Shell component 12B is at least partially made of a material having passive magnetic properties in accordance with the present invention such that the magnet 16 forms a magnetic connection with the base 12 by way of shell component 12B when the container is closed. In an alternative configuration, the magnet 16 may be disposed at a lower portion of the top 14 to form a magnetic connection with a lower portion or component of the base 12 which would be made of a material having passive magnetic properties in accordance with the present invention.

In yet another alternative configuration, the magnet 16 may be attached to the base 12 or a component thereof rather than the top 14. For example, the weight 12F shown in Figure 4 may comprise a magnet configured to attract the top 14 which would be made of a material having passive magnetic properties in accordance with the present invention. In such an example, a proximal end of the top 14 may be configured to engage with the base 12 at a location near enough to the magnet (in the position of magnet 12F, shown in Figure 4) to enable sufficient magnetic attraction between the base 12 and the top 14 so as to keep the container 40 in a closed configuration until a user wishes to open the container 40.

As shown in Figure 4, a gap 44 may be configured between the top 14 and base 12 at a location distant from the sealing location of the magnet 16 in order to allow for imperfect dimensional or assembly tolerances of the various components.

In particular, the invention presents the advantage that the component made of passive magnetic material does not generate a magnetic field which would interact with the metallic components of the environment, especially on the production line.

On the production line, the lipstick components, and specifically the base and the top, are manipulated separately, until a final step of assembling.

Conventionally, lipsticks components are transported along the production line on metallic plates, and / or are surrounded by metallic equipments and sensors which detect for instance problems along the line. If a magnetic field is generated, the metallic components would interact with metallic components, and the sensors could be sensitive to the magnetic field. Some specific arrangement must be taken in order to minimize the interaction. The costs of production are increased.

Moreover, magnets are attracted between each other, so that along the production line, a minimum distance must be kept between the elements which comprise a magnet. On the contrary, when it is necessary to form packs, the magnets can repel each other, making impossible to form pack without involving special arrangements. The production rate is reduced in consequence, and the costs are again increased.

In a lipstick, the base 12 requires more manipulation than the top 14. For instance, the base 12 must be subjected to assembling operation with the product movement mechanism, and / or must be filled with a cosmetic product. Then, by making the base 12 in the passive magnetic material, the mentioned disadvantages do not occur for the base. The manipulation operations of the top 14 being limited, the problems caused by the interaction between the magnets 16 fixed to the tops 14 and the environment are minimized in regard of the advantages provided by the invention.

As only one magnet is required and as the magnet can directly interact with any portion of the surface of the component made in passive magnetic material, the bulkiness is significantly reduced. For instance, the top 14 can present a thickness as small as 2 mm. In other words, in the embodiment wherein the container is a lipstick, when the shell component 12B presents an outer diameter of 17 mm, the top 14 can present an outer diameter of 19 mm. The lipstick can then appear slim if required, even with the use of a magnetic seal. In yet another exemplary embodiment, shown in Figure 5, a pen 50 comprises a base 12, a top 14, a magnet 16 and a pen component 52. As will be understood by one skilled in the art, the choice or configuration of the pen component and associated functional mechanisms are not limited and may include any pen component or mechanism known in the art. In the example shown in Figure 5, the magnet 16 is attached to the base 12 and is attracted to the lower portion of the top 14.

The embodiments and examples above are illustrative, and many variations can be introduced to them without departing from the spirit of the disclosure or from the scope of the appended claims. For example, elements and/or features of different illustrative and exemplary embodiments herein may be combined with each other and/or substituted for each other within the scope of this disclosure.