Abstract:
A container with child-resistant fastening means, the container comprising base ( 31 ), a lid ( 32 ), and a hinge ( 33 ) connecting the base ( 31 ) to the lid ( 32 ) and about which the lid ( 32 ) is movable between an open position and a closed position, the fastening means comprising first interlocking means ( 31 A,  32 A) for resisting opening movement of the lid ( 31 ) in a first direction (D) relative to the base portion ( 31 ) and which is releasable upon relative movement between the lid ( 32 ) and base ( 31 ) in a second direction (B), and second interlocking means ( 31 B) which resist relative movement of the lid ( 32 ) and base ( 31 ) in the second direction (B) and which is releasable upon pressure (C) being applied to release means ( 42 A,  42 B) in two spaced apart locations.

Description:
TECHNICAL FIELD 
       [0001]    This invention relates to a container and, more particularly, to a clamshell container having child-resistant features. 
       BACKGROUND 
       [0002]    Clamshell containers comprising a lid portion, a base portion and a hinge portion connecting the lid portion to the base portion and about which the lid portion and/or base portions are moveable between an open configuration end and closed configuration are well known for housing a wide variety of products. Such a container is, for instance, used to house a CD or DVD. 
         [0003]    Containers with a variety of child-resistant features are also known. These features are designed to make it difficult for a young child to accidentally or intentionally open a container where the contents may be potentially harmful, e.g. medication or small objects. 
         [0004]    This invention seeks to provide a clamshell container with fastening means which provide at least some child resistance. 
       SUMMARY OF INVENTION 
       [0005]    According to a first aspect of the invention, there is provided a container with child-resistant fastening means, the container comprising a base portion, a lid portion, and a hinge portion connecting the base portion to the lid portion and about which the lid portion and/or base portion are movable between an open configuration and a closed configuration, the fastening means comprising first interlocking means for resisting opening movement of the lid portion in a first direction relative to the base portion, the first interlocking means being releasable upon relative movement between the lid and base portions in a second direction, and second interlocking means which resist relative movement of the lid and base portions in said second direction, the second interlocking means being releasable upon pressure being applied to release means in two spaced apart locations. 
         [0006]    According to a second aspect of the invention, there is provided a container with child-resistant fastening means, the container comprising a base portion, a lid portion, and a hinge portion connecting the base portion to the lid portion and about which the lid portion and/or base portion are movable between an open configuration and a closed configuration, the fastening means comprising first interlocking means for resisting opening movement of the lid portion in a first direction relative to the base portion, the first interlocking means being releasable upon relative movement between the lid and base portions in a second direction, the lid and base portions being movable relative to each other in said second direction upon pressure being applied to release means in a third direction. 
         [0007]    The clamshell container is preferably formed from a plastics material and preferably formed in one piece. It may be folded from a blank cut from a substantially flat sheet or roll of material. It may also be formed by a moulding process, e.g. vacuum moulding or injection moulding. In some cases, such techniques may also be used together, e.g. a pre-form may be made by vacuum moulding or injection moulding technique and then parts of the container folded to create the base portion and/or lid portion thereof. 
         [0008]    Such plastic containers can thus be formed in one piece and the amount of plastic material used in their manufacture can be relatively small. 
         [0009]    Other preferred and optional features of the invention will be apparent from the following description and from the subsidiary claims. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0010]    The invention will now be further described, merely by way of example, with reference to the accompanying drawings, in which: 
           [0011]      FIGS. 1A and 1B  are perspective views of a first embodiment of a container shown in a closed position (with an outer cover in place in  FIG. 1A  and omitted in  FIG. 1B  to reveal the internal components); 
           [0012]      FIG. 2A-2D  are sectioned, perspective views to show the movements required to open the container of  FIG. 1 ; 
           [0013]      FIG. 3  is a perspective view of the first embodiment in the open configuration; 
           [0014]      FIG. 4A  is a schematic plan view of a second embodiment of a container in a closed position and  FIG. 4B  is a cross-sectional view taken on line B-B or line C-C of  FIG. 4A . 
       
    
    
     DESCRIPTION OF PREFERRED EMBODIMENTS 
       [0015]    The examples described herein relate to containers for housing blister packs which hold pills or other forms of medication. However, it will be appreciated that a container having fastening means of the type described herein may be used to house a wide variety of other articles. 
         [0016]      FIGS. 1-3  illustrate a first embodiment of a container according to the present invention. This container is capable of housing two blister packs—one in the lid portion and one in the base portion (although in some uses only one blister pack may be installed and some other article or leaflet housed in the other portion). This container can be formed by an injection moulding process. 
         [0017]    The container comprises a base portion  31 , lid portion  32  and a hinge portion  33  that connects the base portion  31  to the lid portion. 
         [0018]      FIGS. 1A and 1B  show the container in the closed configuration (with an outer cover  30  removed in  FIG. 1B  to reveal the internal components). The outer cover would typically be a sheet of card which extends across the major external faces of the lid portion  32 , hinge portion  33  and base portion  31  and is adhered or bonded to the plastic injection moulded component shown in  FIG. 1B . 
         [0019]    By forming only the framework of the container of plastic so that the major faces thereof are provided by the outer cover, the amount of plastic material used can be minimised. The outer cover can be securely bonded to the framework so that the security of the container is not compromised. Such an outer cover, may also have information or graphics provided thereon and both faces thereof may be visible. 
         [0020]    One or more blister packs  34  can be inserted in the container through an opening  40  in one end thereof when the base and lid portions  31 ,  32  are in the closed configuration. One or more flaps  45  (shown in  FIG. 1A  but omitted in  FIG. 1B ) or some other form of closure may be provided for closing the opening  40  once the blister packs  34  have been installed in the container. Preferably, the closure  45  is a snap-fit with the aperture so once this has been closed, it cannot be re-opened. 
         [0021]    Whilst blister packs can be inserted through the end slot in the clamshell in the same way as a cardboard carton, it is also possible to slide each of the blister packs into the lid and base portions when in the open configuration through the cut-outs or recesses that form the slot when the container is closed. 
         [0022]    To access the blister packs in order to dispense one or more pills, a detachable part  30 A of the external cover (see  FIG. 1A ) is removed to reveal dispensing apertures  31  located in a dispensing area at one end of the base or lid portions adjacent one end of the blister packs held therein. The container is then opened by simultaneously pressing two buttons  42 A,  42 B on the lid portion  32  adjacent the hinge portion  33 , then sliding the lid portion  32  in a direction perpendicular to the length of the hinge portion to disengage interlocking flanges  31 A,  32 A which extend along the length of the base and lid portions  31 ,  32  so that the lid portion is free to swing open by pivoting about the hinge portion. The two buttons  42 A,  42 B are preferably accessed directly via rectangular apertures  34 B provided in the outer cover  30  as shown in  FIG. 1A . 
         [0023]    The fastening means for releasably holding the container in the closed position will now be described further with reference to  FIGS. 2A-2D .  FIGS. 2A-DC  are perspective views sectioned along line A-A of  FIG. 1B  to illustrate operation of the fastening means.  FIG. 2A  shows the container in the closed position with the lid and base portions  34 ,  31  secured together by engagement between interlocking members  32 A,  31 A which extend along the length of the lid and base portions  32 ,  31 . 
         [0024]    In order to disengage the interlocking members  31 A,  32 A, the lid portion  32  needs to be slid in the direction B (see  FIG. 2C ) relative to the base portion  31 A, i.e. in a direction perpendicular to the hinge axis. However, in the position shown in  FIG. 2A , lid portion  32  is prevented from sliding in direction B by resilient flaps  31 B the ends of which engage portions  32 B of the lid portion  32 . These components thus provide second interlocking means. 
         [0025]    To release the engagement between flaps  31 B and portion  32 B, the buttons  42 A and  42 B are depressed (in direction C) as shown in  FIG. 2B . Ribs on the underside of button  42 A and  42 B then depress the resilient flaps  31 B so they are no longer aligned with portions  32 B of the lid portion  32 . 
         [0026]    Whilst button  42 A and  42 B are depressed, the lid portion  32  can then be slid in the direction B relative to the base portion  31  as shown in  FIG. 2C  whereby the interlocking members  32 A,  31 A disengage from each other. The lid portion  32  can then be pivoted in direction D about the hinge axis so as to open the container. 
         [0027]      FIG. 2D  is a perspective sectioned view corresponding to  FIG. 2C  but shown from a different angle. 
         [0028]    To release the second interlocking means, both of the buttons  42 A need to be simultaneously depressed. The two buttons  42 A are spaced apart from each other so, in general, two hands are required to depress them. 
         [0029]      FIG. 3  shows the container in the open configuration with a blister pack  34 A housed in the lid portion  32  and a blister pack  34 B housed in the base portion  31 . Each blister pack has an array of blisters  34 C provided thereon and an intermittent rib (not shown) adjacent the edges of the blister pack. The intermittent rib is formed by a series of spaced projections (but could also comprise a continuous rib of varying height). At the end of each intermittent rib, a further projection  34 E is formed to provide a stop feature. The intermittent ribs and stop feature are preferably formed as additional blisters along the sides of the blister pack. A tool for manufacturing standard blister packs can be easily modified to provide the intermittent rib and stop feature on the sides of the blister pack e.g. by cutting extra features in the mould within the existing template for the blister pack. 
         [0030]    A channel  43  is formed along the edges of both the lid and base portion  31 ,  32  to receive the intermittent ribs. Thus, when a blister pack is inserted into the open end of the container, the ribs are located in the respective channels  43  and then slid along the channels to the storage position shown in  FIG. 2 . The channel may be continuous as shown or comprise a series of separate sections which provide the same function. 
         [0031]    To dispense one or more pills from a blister pack  34 , the blister pack  34  is slid in direction A to a position in which the first line of blisters is located over the dispensing apertures  41 A,  41 B. These apertures are provided in a ramp  44  towards one end of the base portion  31  or lid portion  32 . A removal area is thus defined beneath each ramp  43  which is in communication with the exterior of the container (once the detachable part of the external cover referred to above has been removed). The use of inclined ramps  44 , enables a dispensing space to be created in both the lid and base portions  31 ,  32  without increasing the overall depth of the container. Once a blister has been aligned with one of the apertures  41 , it can be pressed to dispense a pill through the aperture  41  and into the removal area from where it can fall onto a surface or into a user&#39;s hand. 
         [0032]    The blister pack  34  is flexed about a line extending across its width into a curved form as it is slid up the ramp  44 . This helps ensure that the longitudinal edges of the blister pack  34  remain located beneath the channels  43  as it is then very difficult for the blister pack  34  to be simultaneously bowed or curved about a line extending along its length to withdraw its edges from beneath the channels  43 . 
         [0033]    After pills have been dispensed from the first line of blisters, the blister pack  34  is slid further along so the second row of blisters is aligned with the dispensing apertures  41  and so on until the last line of blisters is reached. 
         [0034]    Graphics are preferably provided in the container which are gradually revealed as the blister pack is slid out. Typically, such graphics would indicate time intervals appropriate to the medication housed in the blister pack, e.g. the days of the week and/or the time of day (morning, afternoon, evening, night). 
         [0035]    The intermittent ribs along the sides of the blister pack are preferably arranged to interact with a resilient flap  43 A at the end of each channel  43  to provide an indexing mechanism whereby as each projection of the intermittent rib is pulled past the flap  43 A, a respective line of blisters is positioned over the dispensing apertures  41  until the stop feature  34 E is reached. This is shaped so that it cannot be pulled past the resilient flap  43 A (except by application of an excessive force) so that the blister pack  34  is effectively trapped in the container. The stop feature  34 E may be hook-shaped so it engages part of the lid/base portion and so prevents the blister pack being separated from the container. 
         [0036]    After pills in each line of blisters have been dispensed, the blister pack  34  may be pushed back into the container so it returns to the storage position shown in  FIG. 2 . The projections of the intermittent rib are shaped so they can slide back past the resilient flap  43 A relatively easily. The lid and base portions can then be moved to the closed configuration whereby the blister pack is no longer accessible from outside the container. Alternatively, the blister pack  34  can be left projecting from the container (or cut off), although this is not preferred as some of the child resistant features may then be circumvented and it may prevent closure of the container. 
         [0037]    In an alternative embodiment, a locking feature, e.g. one or more projections (not shown) may be provided on the lid portion to prevent a blister pack housed in the base portion from being slid out of the container when the container is in the closed position so that a user has to open the container before either of the blister packs  34  can be slid further out of the container. 
         [0038]    The container shown in  FIGS. 1-5  is also provided with booklet clips  45  adjacent the hinge portion  33  so that when the container is in the open configuration a booklet housing area  46  is provided in the centre of the container (as shown in  FIG. 2 ). Booklets housed in recessed area  46  would be supported at their edges by flanges  46 A,  46 B of the lid and base portions  31 ,  32 , respectively, and by the external cover (not shown) which would extend across the underside of the container in the open configuration shown in  FIG. 2 . 
         [0039]    The booklet clips  45  are preferably similar to those widely used in DVD containers. These comprise a resilient arm with a free end such that a booklet or other sheet material can be slid beneath the free end so as to be resiliently held in the literature receiving area. A booklet may be preloaded into area  46 , i.e. before the lid and base portions  31 ,  32  are moved to the closed configuration. A booklet housed in area  46  does not therefore interfere with the loading or dispensing of the blister packs. 
         [0040]    As well as providing a separate area lying between the two blister packs  34 A,  34 B for holding and/or displaying literature and graphics material, sheet material located within area  46  is folded or bent into a curved shape when the container is moved to the closed configuration. It has been found that such folded or curved sheet material acts as a resilient element which urges the lid and base portions  31 ,  32  apart, and thus assists in opening the container, once fastening means holding the lid and base portions  32 ,  33  in the closed configuration is released. 
         [0041]    Other resilient means, e.g. a resilient arm extending from the base and/or lid portions may be used in place of, or in addition to, sheet material in area  46  to urge the lid and base portions apart once released. 
         [0042]    In the container described above, the hinge portion  33  extends along the long edge of the container and the blister packs are arranged to slide in a direction substantially parallel to the hinge axis about which the lid and base portions rotate. This is the preferred arrangement as, when the container is in the open configuration, it then has an approximately square perimeter. However, it is also possible for the hinge to be provided along a short edge of the container (as it is in the other embodiments described above). In this case, the blister packs may slide out over the hinge portion (particularly if they are inserted into the container through an opening in the edge opposite the hinge portion) although they may also be arranged to slide away from the hinge portion. 
         [0043]    It will be appreciated from the above description that each edge of the container provides a separate function: one long edge provides the hinge portion (as well as the booklet clips  45  and release button  42 B), the other long edge provides the interlocking flanges  31 A,  31 B, one short edge provides the opening  40  though which blister packs (and additional literature) can be inserted and the other short edge provides the dispensing apertures  41 A,  41 B and the removal area defined beneath these apertures. Such an arrangement is thus highly space efficient. 
         [0044]    As described above, in some of the embodiments the lid and base portion of the container define an aperture or slot in the closed configuration through which one or more blister packs (and, optionally, compliance literature) can be inserted into the container. The ability to load blister packs into a clamshell container in this manner provides significant advantages, as the container can then be filled in a conventional filling line, e.g. as used to load blister packs into conventional cardboard cartons or plastic sleeves. 
         [0045]    Thus, it will be appreciated that, in the preferred embodiments, the blister pack(s) can be both slid into the container and slid out of the container as articles are dispensed. Preferably, the blister packs are slid into one end of the container and slid out of the opposite end. 
         [0046]      FIG. 4A  shows a schematic plan view of a second embodiment of a container according to the present invention in a closed position.  FIG. 4B  shows a cross-section of the container taken along line B-B (or C-C) of  FIG. 4A . 
         [0047]    The second embodiment comprises a lid portion  51 , base portion  52  and hinge portion  53  which are moulded together (in the open position) by a press moulding or vacuum moulding technique from a sheet of plastic material. 
         [0048]    As shown in  FIG. 4B , the lid and base portions are held together in the closed position by interlocking members  51 A and  52 A. In order to open the container, it is necessary to slide the lid portion  51  in the direction D relative to the base portion  52  in order to disengage the interlocking members  51 A,  52 A from each other. 
         [0049]    To slide the lid portion  51  in the direction D, a user depresses a button  51 B in the direction E. The lid and base portions each have wedge-shaped portions  51 C,  52 C either side of the button  52  whereby downward pressure on wedge shape  51 C causes it to slide over the wedge shape  52 C so that pressure in direction E is converted to movement of the lid portion  51  in direction D. The interlocking members  51 A,  53 A thus disengage from each other so that the lid portion can be opened in direction F about the hinge axis. In a preferred embodiment, once released, the lid portion moves in the direction F as tension in the hinge portion  53  is relaxed. 
         [0050]    Movement of the lid portion  51  in direction F is thus prevented until the lid portion has first been moved in direction D. This is achieved by pressure being applied in direction E which is converted to movement in direction D. 
         [0051]    The containers described have fastening means that are preferably designed to be child resistant whilst also being senior friendly. First, in a preferred arrangement, the clamshell can only be opened by pressing two buttons (generally requiring two hands) and then a sliding movement in a different direction to release interlocking features. In the first embodiment, the buttons need to be depressed in order to disengage further interlocking means, followed by a sliding action. In the second embodiment, depression of the buttons is converted into the sliding movement but no further interlocking means are provided. A further embodiment could, however, provide both these features, i.e. second interlocking means and conversion means to convert pressure in one direction to movement in another. 
         [0052]    In addition, in the first embodiment once the container has been opened, the flat, rupturable face of the blister pack lies against the lid or base portion so cannot be directly accessed. Instead, the blister pack has to be slid to a dispensing position before a pill can be ejected from a blister and a detachable portion of the outer cover has to be removed before the ejected pill can be reached. A similar arrangement could also be provided in the second embodiment. 
         [0053]    A series of steps and actions is thus required which significantly reduces the chance that a young child will either accidentally (or intentionally) gain access to the pills. The features of the container and the movements required are, however, such that the majority of elderly people should be able to operate the container without difficulty. 
         [0054]    The use of a clamshell container enables such child-resistant features to be used, as it is necessary to move the container to an open configuration before the contents can be accessed. 
         [0055]    The embodiments described above provide a wide variety of features. Many of these features can be inter-changed between embodiments. Further embodiments are thus envisaged which use a selection of the features from those described above. The invention thus extends to cover containers having other combinations of the features described.