Patent Publication Number: US-11026527-B2

Title: Collapsible cup

Description:
FIELD OF THE INVENTION 
     The present invention relates to collapsible containers. More particularly, it relates to shape-retaining collapsible containers such as cups, mugs or glasses for holding potable liquids for consumption by a user. 
     BACKGROUND 
     People have been buying collapsible mugs for a variety of reasons. In some cases, the containers are collapsed and kept in a purse and expanded and used when the owner obtains a beverage such as at a coffee shop. In this way, the use and disposal of disposable containers is avoided. In other case, the containers are used by travelers including hikers and campers who need to pack the container into a small space. Collapsible mugs are also purchased by people living in small living spaces such as apartments. 
     It has been found that collapsible containers generally and mugs particularly can be difficult to make reliably when the containers and mugs have to be water tight. 
     Additionally some configurations of collapsible containers, particularly ones with five tiers, naturally have narrow bases which are problematic for mugs which already tend to be tall and narrow. Further narrowing the base makes it more likely that the collapsible mug will be knocked over. 
     It has also been found that some collapsible mugs have poor collapsibility. 
     It has also been found that some collapsible mugs are difficult to expand except by pushing the bottom out from the inside. This is generally non-hygienic. 
     Some collapsible mugs have a chunky appearance or are otherwise unsightly. 
     Collapsible mugs are by their collapsible nature made of flexible material that can fold when the mug is collapsed. However, this material typically offers little or no resistance to deformation caused by lateral forces, such as an object bumping into or pressing against the side of the container, or a user attempting to grasp or lift the container by the flexible wall section, which could result in the contents being spilled. 
     Previous designs for collapsible mugs have not had handles with openings for fingers to grip the handle. Some users prefer such a handle when the beverage in the mug is very hot or cold. 
     A need therefore exists for a collapsible mug that is easier to manufacture, does not have an overly narrow base, has good collapsibility, can be hygienically expanded easily, looks good, can be easily grasped without deforming the mug and has a handle with an opening for one or more fingers. Additionally, the mug needs to be self-supporting in at least a fully collapsed and a fully expanded state and water tight. 
     SUMMARY OF THE INVENTION 
     A collapsible container of a flexible material is provided. It has a flexible body including (1) a plurality of tiers including a top tier, a middle tier and a bottom tier and (2) a plurality of living hinges including a first living hinge between the top tier and the middle tier and a second living hinge between the middle tier and the bottom tier. The bottom tier has a base. The container also has a rigid plate at least partially embedded in the bottom tier that makes the otherwise flexible base rigid. Preferably the containers have a volume of 50-2000 ml, more preferably 100-1500 ml, and most preferably 200-1000 ml. 
     Preferably, the container has a collapsed state in which the bottom tier is at least partially located within the top tier. The container in the collapsed state may be expanded to an expanded state by gripping the exterior of the base and pulling the base away from the top tier. The container may also have a rigid cladding providing rigidity to the top tier so that the container may be easily gripped around the top tier. 
     Preferably, the container has a rigid cladding providing rigidity to the top tier so that the container may be easily gripped around the top tier. The top tier may have an elastomeric grip around the rigid cladding. The top tier may have a handle having an opening for one of more fingers. The handle may have an internal rigid ring and an elastomeric material covering the internal rigid ring and joining the handle to the flexible body, the handle being rigid and rigidly joined to the flexible body. 
     Preferably, the container has a rigid cladding providing rigidity to the top tier so that the container may be easily gripped around the top tier. The container may have a top opening and a removable lid having a selectively closable opening. The lid may have a circumferential sealing protuberance, which is in contact with the top tier when the lid is fully inserted into the top opening. The container may have a rim around the top opening. The rim is covered by the rigid cladding, which has an underside inside the container. The protuberance is in contact with the underside of the rigid cladding. 
     Preferably, the top tier is adjacent the middle tier and the bottom tier is adjacent the middle tier when the container is in the expanded state. Preferably, the middle tier is more flexible than the top and bottom tiers. 
     Preferably, the container has a sidewall extending below the top tier and the sidewall has a smooth appearance. 
     Preferably, the rigid plate improves the collapsibility of the container. 
     Preferably, the rigid plate has an outer portion embedded into the bottom tier and a central portion having a recess that is either above or below the outer portion. The flexible body fills the recess to maintain the rigid plate at least partially embedded in the bottom tier. The metal plate may be visible from below the container or through an opening in the top tier. 
     Preferably, the flexible body is unitary and watertight. 
     A method of manufacturing a collapsible container of flexible material is provided. The method includes placing a rigid plate inside a bottom portion of a mold and injecting a flexible material into the mold and around the rigid plate in the mold. The mold is configured to form the collapsible container. The collapsible container has a body of the flexible material, the body including (1) a plurality of tiers including a top tier, a middle tier and a bottom tier and (2) a plurality of living hinges including a first living hinge between the top tier and the middle tier and a second living hinge between the middle tier and the bottom tier. The bottom tier has a base. The bottom portion of the mold corresponds to the bottom tier of the collapsible container. The rigid plate makes the otherwise flexible base rigid. 
     Preferably, the method includes placing a rigid cladding preform in the mold. The injecting includes injecting the flexible material into contact with the rigid cladding preform to form the collapsible container with rigid cladding. 
     Preferably, the method includes placing a handle preform having a ring in the mold. The injecting includes injecting the flexible material into contact with the handle preform to form the container with a handle. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a collapsible mug according to one aspect of the invention, in a fully expanded state. 
         FIG. 2  is an elevation view of the mug in  FIG. 1  in the fully expanded state. 
         FIG. 3  is a partially exploded, plan view of the mug in  FIG. 1  from above in the fully expanded state. 
         FIG. 4  is a cross-sectional elevation view of the mug of  FIG. 1  in the fully expanded state along line  4 - 4  shown in  FIG. 2 . 
         FIG. 5  is an elevation view of the mug of  FIG. 1  in the fully collapsed state. 
         FIG. 6  is a cross-sectional elevation view of the mug of  FIG. 1  in a fully collapsed state along line  6 - 6  shown in  FIG. 5 . 
         FIG. 7  is a partially exploded, plan view of the mug in  FIG. 1  from below in the fully collapsed state. 
         FIG. 8  is a perspective view of a collapsible mug according to another aspect of the invention, in a fully expanded state. 
         FIG. 9  is an elevation view of the mug in  FIG. 8  in the fully expanded state. 
         FIG. 10  is a plan view of the mug in  FIG. 8  from above in the fully expanded state. 
         FIG. 11  is a cross-sectional elevation view of the mug of  FIG. 8  in the fully expanded state along line  11 - 11  shown in  FIG. 10 . 
         FIG. 12  is a plan view of the mug of  FIG. 8  in the fully collapsed state. 
         FIG. 13  is a cross-sectional elevation view of the mug of  FIG. 8  in a fully collapsed state along line  13 - 13  shown in  FIG. 12 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Collapsible containers in accordance with the present invention are described in this section, with reference to a mug  20  depicted in  FIGS. 1-7  and a collapsible mug  120  having a handle depicted in  FIGS. 8-13 . The term mug as used herein refers to handheld containers having a narrow base relative to its top which are used for drinking. Therefore, the term mug refers to containers such as cups and glasses. Preferably the containers have a volume of 50-2000 ml, more preferably 100-1500 ml, and most preferably 200-1000 ml. 
     With reference to  FIGS. 1-7 , mug  20  according to one embodiment of the invention is described and illustrated. Mug  20  has a lid  22  and a flexible body  26 , which is preferably unitary and preferably watertight, and made from a flexible material. Body  26  has an opening  28  which is covered by lid  22 . Body  26  preferably has three tiers, top tier  30 , a middle tier  32  and a bottom tier  34 . Each tier is substantially cylindrical. 
     Mug  20  has a rim  36  and a metal cladding  40  which covers rim  36  and most of the outside of top tier  30 . Metal cladding  40  also covers part of the inside of top tier  30 . Metal cladding  40  has a hook  42  which is embedded into top tier  30  around a circumference  44  of top tier  30 . Hook  42  can be completely bent back as in a fishing hook, but is sufficient that it angle into top tier  30  so that it is held by tier  30 . Cladding  40  has a circumferential recessed portion  46 . An elastomeric grip  48  resides in recessed portion  46 . Elastomeric grip  48  is of sufficient height to make it easy to grip mug  20  even if the outside of top tier  30  is wet. Cladding  40  makes top tier  30  rigid. 
     Middle tier  32  is located between top tier  30  and bottom tier  34 . Middle tier is preferably flexible relative to top tier  30  and bottom tier  34 . It has a sidewall  49 . 
     Bottom tier  34  has a sidewall portion  50  and a base portion  54  which is part of base  52  of mug  20 . Sidewall portion  50  is stiff although made from a flexible material relative to sidewall  49 , which is generally thinner than sidewall portion  50 . Mug  20  has a metal plate  56 , which is a generally circular or disc shaped with a raised central portion  58  and an annular flange portion  60 . Portion  60  has an outer annulus  62  that is embedded into bottom tier  34  proximate to where sidewall portion  50  meets base portion  54 . Base portion  54  has a raised central portion  66  which follows the underside of plate  56  to better maintain plate  56  in place and is also raised such that it would not contact a flat surface on which mug  20  is placed. As shown none of plate  56  is visible from a perspective beneath base portion  54 . Bottom tier  34  can vary from the above description in several ways. Base  52  need not be entirely raised off the surface on which mug  20  is placed. Base portion  54  may not cover the entirety of the underside of plate  56  in which case plate  56  could have a circumferential hook (not shown) like hook  42 . Plate  56  could not have raised central portion  58  in which case plate  56  could have the circumferential hook. Alternatively, instead of raised central portion  58 , plate  56  could have a depressed central portion (not shown) and rather than base portion  54  being underneath plate  56 , base portion is over plate  56  and follows the top side of plate  56  to better maintain plate  56  in place. 
     Flexible body  26  has a plurality of living hinges, preferably two, including a first living hinge  70  and a second living hinge  72 . First living hinge  70  is located between top tier  30  and middle tier  32 . Second living hinge  72  is located between middle tier  32  and bottom tier  34 . Preferably, first and second living hinges  70 ,  72  connect the tiers that they are located between. Living hinges  70  and  72  are shown as being folded in  FIGS. 5-7  which illustrate mug  20  in a fully collapsed state and unfolded in  FIGS. 1-4  which illustrate mug  20  in a fully expanded state. It is also possible for one of living hinges  70  and  72  to be folded and the other to be unfolded in a partially collapsed state. 
     Lid  22  covers opening  28 . Lid  22  has an aperture  74  for dispensing liquid, which may be closed or covered by a slide  76  having an upstanding tab  78 . Slide  76  may move between open and closed positions by rotation (not shown) or translation. Slide  76  where shown is shown in the closed position in  FIGS. 1-7 . Slide  76  has prongs  79  which pass through slide apertures  80  in lid  22 . Prongs  79  and slide apertures  80  serve to guide slide  76  and attach slide  76  to lid  22 . Lid  22  has a circular sidewall  82  having one or more stiff or flexible protuberances  84  (in the form of lips) forming an annulus around sidewall  82  as best shown in  FIGS. 4 and 6 . When lid  22  is fully inserted into mug  20  as shown in  FIGS. 4 and 6 , at least one of protuberances  84  engage top tier  30  below the bottom  88  of metal cladding  40  on the inside of mug  20 . Protuberances  84  seal the mug and secure lid  22  to mug  20 . Advantageously, one of protuberances  84  contacts the underneath of bottom  88  to better secure lid  22 . Protuberances  84  may be made from any suitable flexible material including silicone. Lid  22  also has a rim  90  that sits on top of rim  36  having a tab  92  for removing lid  22  from mug  20 . 
     With reference to  FIGS. 8-13 , mug  120  according to another embodiment of the invention is described and illustrated. Mug  120  has a flexible body  126 , which is preferably unitary and preferably watertight, and made from a flexible material. Body  126  has an opening  128 . Body  126  preferably has three tiers, top tier  130 , a middle tier  132  and a bottom tier  134 . Top tier  130  is substantially cylindrical, but tier  134  is substantially frusto-conical and tier  132  can be substantially cylindrical or frusto-conical. 
     Mug  120  has a rim  136  and a metal cladding  140  which covers rim  136  and most of the outside of top tier  130 . Metal cladding  140  also covers part of the inside of top tier  130 . Metal cladding  140  has a hook  142  which is embedded into top tier  130  around a circumference  144  of top tier  130 . Hook  142  can be completely bent back as in a fishing hook, but is sufficient that it angle into top tier  130  so that it is held by tier  130 . Preferably the angle is approximately 90 degrees. 
     Attached to top tier  130  is a handle  146  having an opening  148  for one or more fingers to grip handle  146 . In this invention, handle  146  is be considered to be attached to mug  120  and top tier  130  even if tier  130  and handle  146  are molded in the same molding operation. As can best be seen in  FIGS. 11 and 13 , handle  146  has an internal ring  150 , which is rigid and provides rigidity to handle  146 . Internal ring  150  has a ring shape that is flattened in the vicinity of cladding  140 . Suitable rigid materials for internal ring  150  include metal, which can be the same as cladding  40  and  140 . Around internal ring  150  is the same flexible material as body  126 . Surprisingly, despite the material being flexible, the connection (as indicated by number  152 ) of handle  146  to tier  130  is substantially rigid because of inter alia the proximity of internal ring  150  to cladding  140  and the large area of connection  152 , the area being perpendicular to the cross-sections shown in  FIGS. 11 and 13 . Alternatively metal cladding  140  and internal ring  150  can be joined directly to each other such as by a welding operation to provide rigidity to the connection of handle  146  to tier  130 . Cladding  140  has an opening  158  so that a molten thermoplastic or uncured plastic or elastomer can flow through opening  158  during the molding of mug  120 . Advantageously, opening  158  allows mug and handle to be easily molded together such that connection  152  is rigid. This rigidity is important because otherwise liquid in mug  120  could spill out if mug  120  sagged relative to handle  146 . 
     Middle tier  132  is located between top tier  130  and bottom tier  134 . 
     Bottom tier  134  has a sidewall portion  160  and a base portion  164  which is part of base  162  of mug  120 . Mug  120  has a metal plate  166 , which is a generally circular or disc shaped with a raised central portion  168  and an annular flange portion  170 . Portion  170  has an outer annulus  172  that is embedded into bottom tier  134  proximate to where sidewall portion  160  meets base portion  164 . Base portion  164  has a raised central portion  176  which follows the underside of plate  166  to better maintain plate  166  in place and is also raised such that it would not contact a flat surface on which mug  120  is placed. As shown none of plate  166  is visible from a perspective beneath base portion  164 . Bottom tier  134  can vary from the above description in the same ways as bottom tier  34  discussed earlier. 
     Flexible body  126  has a plurality of living hinges, preferably two, including a first living hinge  180  and a second living hinge  182 . First living hinge  180  is located between top tier  130  and middle tier  132 . Second living hinge  182  is located between middle tier  132  and bottom tier  134 . Preferably, first and second living hinges  180 ,  182  connect the tiers that they are located between. Living hinges  180  and  182  are shown as being folded in  FIG. 13  which illustrates mug  120  in a fully collapsed state and unfolded in  FIGS. 8-11  which illustrate mug  120  in a fully expanded state. It is also possible for one of living hinges  180  and  182  to be folded and the other to be unfolded in a partially collapsed state. Mug  120  has a flexible sidewall  184  below the top tier. Advantageously, flexible sidewall  184  has a smooth appearance similar to a ceramic tea cup for aesthetic reasons. This smooth appearance is achieved by making the exterior of living hinges  180  and  182  follow the smooth contour of middle tier  132  and sidewall portion  160  of bottom tier  134 . In part this is achieved by making living hinges thinner by removing material from the inside of body  126 . 
     Mug  120  is shown without a lid. However, it could have a lid similar to lid  22 . 
     Benefits of the collapsible mugs of the invention include easier manufacture. The unitary construction of the flexible body which if watertight, e.g., without holes in the base, means the collapsible mug is also watertight without risk of failure at joints causing leaking. The three tier construction of the collapsible mug allows the mug to have a wider base than a five tier construction. The use of a metal or rigid plate improves the collapsibility of the collapsible mug as the rigid base does not deform during an attempted collapse and improves the stability of the mug. The collapsible mugs also have an esthetically pleasing appearance particularly if the cladding is metal and if the sidewalls of the bottom and middle tiers are smooth. The cladding of the top tier make the mug easy to hold as does the handle. 
     Mugs of the invention may be made by overmolding onto a metal cladding preform, a metal plate and optionally a ring or handle preform preferably in a single overmolding operation to produce a unitary and watertight flexible body which is integrated with a metal cladding, the metal plate and a handle including the ring. Before the overmolding operation, the metal cladding preform, the metal plate and optionally the ring would be loaded in a mold for the mug. During the overmolding, a flexible material is injected into the mold and flows into contact with the metal cladding preform. When making a mug with a handle, the metal cladding preform has an opening such as opening  148  to permit the overmolding material to flow through the opening so that the overmolding material flows between the body portion of the mold and the handle portion of the mold. Any lids would generally be made separately. 
     Of course, in the context of containers according to the present invention, as in common parlance, it will be understood that “stiff,” “rigid,” and “flexible” are relative terms. Thus unless further specified, referring to a tier as “stiff” herein simply means, at a minimum, that the tier is stiff enough to impart a force to its neighboring flexible tier or tiers sufficient to fold the flexible tier or tiers between relatively folded and unfolded stable positions (optionally causing the flexible tiers to “snap” between positions), without itself folding (i.e., without inverting its vertical orientation, with respect to the top and bottom of the container). On the other hand, a tier that is considered “rigid” for purposes of the invention typically will not even appreciably yield or deform, let alone fold, in the direction of the force imparted to fold the flexible tiers, in response to either that force or other typical loads associated with normal use of the container. Still further, a rigid tier preferably will not appreciably deform in any direction during normal use of the container. A “rigid” tier that exhibits the latter characteristic of not appreciably deforming in any direction is typically formed of a different material than the flexible tiers, rather than the same material in a different size or geometric configuration. Finally, all “rigid” structures and materials are also to be considered stiff, and structures or materials referred to as “stiff” may or may not be rigid, unless expressly stated as not being rigid but only stiff. 
     Although each flexible tier of the various containers described herein is illustrated as having only two stable positions, it is also within the scope of the invention to provide one or more flexible tiers having a plurality of stable partially expanded positions, for example by providing one or more flexible tiers having a stepped profile comprising a series of accordion-like pleats of flexible material, the pleats comprising peripheral bands of material oriented in alternating directions and connected to adjacent bands by living hinges, so that each pleat can be independently folded and unfolded (not shown), being stable in either state. Also, a wall structure of a container according to the invention need not have the exact shapes of the containers shown in the Figures, but may have any suitable shape, such as round, oval, rectangular with rounded corners, or other shape as desired. For example, successive accordion pleats may be stable in relatively “bent” orientations, in which part of the circumferential length of a pleat is folded and the remainder of the length is unfolded. 
     The flexible body of the containers of the invention may be made from any suitable flexible material including food grade silicone and thermoplastic elastomers. The metals used in the containers of the invention include stainless steel, aluminum, and iron. To prevent corrosion, the metal may have any suitable coating. Stainless steel is preferably not coated and can have any suitable finish including brushed or polished. Suitable rigid materials that could be used instead of metal include nylon and polypropylene. 
     In the context of containers according to the present invention, the living hinge is thinner than the surrounding material, e.g., adjacent tiers, and may be repeatedly folded and unfolded over 100 times without damaging the hinge. 
     While the invention has been described with respect to certain embodiments, as will be appreciated by those skilled in the art, it is to be understood that the invention is capable of numerous changes, modifications and rearrangements, and such changes, modifications and rearrangements are intended to be covered by the following claims.