Abstract:
The plastic container has a lid and a receptacle, the receptacle and lid having corresponding engagement portions matingly shaped for the lid and receptacle to be maintained in a closed configuration by a resilient effect. In one embodiment, the lid has a handle lip extending vertically downwardly from a horizontal edge of the lid, the handle lip being shaped to allow over-coming the resilient effect when manually pulled upwardly; the receptacle having a barrier strip covering the handle lip and pre-venting manual pulling access thereto, but being tearable to allow its manual removal. In an other embodiment, the receptacle has an upwardly protruding receptacle rib providing sealing abutment support to the lid closure, a gutter surrounding the receptacle rib, and the receptacle wall portion has an engagement portion matingly shaped to resiliently receive the outwardly protruding rib of the lid and inclined so as to face both inwardly and downwardly.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority of U.S. provisional application 61/364,846 filed Jul. 16, 2010 by applicant. 
     
    
     FIELD 
       [0002]    The improvements generally relate to the field of plastic containers, and more particularly to tamper-evidence and leak proof characteristics thereof. 
       BACKGROUND 
       [0003]    It is well known to use plastic containers to sell many types of goods. For instance, it is commonplace in the art that goods such as food or fasteners be provided in plastic containers. 
         [0004]    Such plastic containers can be made of various types of plastics, and can be made by thermoforming or injection, for instance. 
         [0005]    For the purchaser of such goods to feel confident about the purchase, various means to prevent tampering with the goods have been presented in the past. Some of these deal with making the container more difficult to open, such as requiring a tool for instance. Another approach has been to design the container in a manner that opening it requires breakage of a component, thereby presenting evidence that the container had been tampered with. Although many different designs were presented in the past, many of which were satisfactory to a certain degree, there still remained room for improvement. 
         [0006]    Furthermore, for containing liquids, there remained room for improved containers having a satisfactory seal formed between the lid and the receptacle. 
       SUMMARY 
       [0007]    In accordance with one aspect, there is provided a plastic container having a lid and a receptacle, the receptacle and lid having corresponding engagement portions matingly shaped for the lid and receptacle to be maintained in a closed configuration by a resilient effect, the lid having a handle lip extending vertically downwardly from a horizontal edge of the lid, the handle lip being shaped to allow overcoming the resilient effect when manually pulled upwardly; the receptacle having a barrier strip covering the handle lip and preventing manual pulling access thereto, but being tearable to allow its manual removal. 
         [0008]    In accordance with another aspect, there is provided a plastic container comprising: a lid having a lid rim, a handle lip extending downwardly from an outer side of the lid rim and having a free lower end, a closure parallel to and downwardly offset from the lid rim, and a lid wall upwardly connecting a periphery of the closure to an inner side of the lid rim, the lid wall having an outwardly protruding rib; a receptacle having a receptacle rim, a receptacle wall portion extending downwardly from an inner side of the receptacle rim, the receptacle wall portion having an inwardly protruding portion shaped to resiliently trap the rib of the lid below it, and a tearable barrier strip detachably connected to the receptacle rim and being shaped as an elongated U to house the handle lip and prevent manual access to at least the free lower end thereof; whereby the lid is manually openable only after the barrier strip has been teared away to provide manual access to the handle lip. 
         [0009]    In accordance with another aspect, there is provided a plastic container comprising: a lid having a lid rim, a closure parallel to and downwardly offset from the lid rim, and a lid wall upwardly connecting a periphery of the closure to an inner side of the lid rim, the lid wall having an outwardly protruding rib; a receptacle having an upwardly protruding receptacle rib providing sealing abutment support to the lid closure, a gutter surrounding the receptacle rib, and a receptacle wall portion projecting upwardly from an outer side of the gutter, the receptacle wall portion having an engagement portion matingly shaped to resiliently receive the outwardly protruding rib of the lid and inclined so as to face both inwardly and downwardly in a manner to further exert upon the outwardly protruding rib a sealing force which presses the lid closure against the receptacle rib. 
     
    
     
       DESCRIPTION OF THE FIGURES 
         [0010]    In the figures, 
           [0011]      FIG. 1  is a perspective view of an embodiment of a plastic container; 
           [0012]      FIG. 2A to 2D  are successive views showing closing and opening of the plastic container of  FIG. 1 ; 
           [0013]      FIG. 3  is a cross-sectional view of the plastic container of  FIG. 1 ; and 
           [0014]      FIG. 4A to 4C  are enlarged cross-sectional views corresponding to  FIGS. 2A to 2C , respectively. 
       
    
    
     DETAILED DESCRIPTION 
       [0015]      FIG. 1  shows an embodiment of a plastic container  10 . The plastic container  10  can be seen to be generally comprised of a receptacle  12  and a lid  14 , both of which are made of a thin sheet of plastic. It will be understood by those skilled in the art that an embodiment such as shown or similar can be realised by thermoforming or injection moulding from a wide variety of plastics, for example. In this particular embodiment, the plastic container  10  is thermoformed and the lid  14  is connected to the receptacle by a hinge  16 . Further, this particular embodiment is designed to be stackable in either one of the closed and open configurations as can be appreciated from the illustration. 
         [0016]    More particularly, still referring to the embodiment shown in  FIG. 1 , the inner wall  18  of the lid  14  and the upper internal portion  20  of the receptacle  12  are provided with mating engagement portions ( 22 ,  24 — FIG. 3 ) which are resiliently engaged with one another when the lid  14  is closed on the receptacle  12  and thereafter maintained in engagement by a resilient effect due to the shape of the plastic container and the elasticity of the material it is made of. This will be detailed further below with reference to  FIGS. 4A to 4B . 
         [0017]    The receptacle  12  has a barrier strip  26  which surrounds the entirety, or quasi-entirety of the cavity  28  to the exception of the hinge  16 . The barrier strip  26  has a U-shaped channel  30 , better seen on  FIG. 3 , and is independent from the engagement portion  24  of the receptacle  12  (i.e. it has no part in the resilient effect which maintains the lid  14  engaged with the receptacle  12  once closed). The barrier strip  26  is detachable from the remainder of the receptacle  12  by tearing along a tear line  32 , and one tab  34  or more can be provided to help holding the barrier strip  26  when detaching it from the remainder of the receptacle  12 . The lid  14 , on the other hand, has a handle lip  36  which projects substantially normally from the lid rim  38 , in the same direction than the lid closure  40  also projects from the lid rim  38 . 
         [0018]    Turning to  FIG. 2B , it can be appreciated that the plastic container  10  is configured in a manner that the handle lip  38  is effectively nested in the U-shaped channel  30  of the barrier strip  26  when the lid  14  is engaged with the receptacle  12 . In this configuration, an average person cannot reach the free lower end of the handle lip  38  of the lid  14  with his/her fingers because the opening between the handle lip  38  and the outer wall  42  of the barrier strip  26  is too small. An average person therefore finds no grip to open the lid  14 . The lid  14  is thus prevented from being manually opened from the closed position by the combination of the resilient effect of the engagement ( 22 ,  24 — FIG. 3 ) portions and the barrier strip. To restore manual access to the handle lip  36 , the barrier strip  26  must be at least partially detached (i.e. torn along the tear line  32 — FIG. 1 ), which leaves irreversible evidence of tampering. 
         [0019]    Turning to  FIG. 2C , once a consumer purchases the goods with the plastic container  10 , the consumer can remove the barrier strip  26  in one easy step, thereby freeing the handle lip  36  from the barrier. The plastic container  10  can then be easily manually opened into the configuration shown in  FIG. 2D  by pulling the handle lip  36  upwardly. It will be appreciated by those skilled in the art that the embodiment shown in the attached figures can thereafter be opened and closed more than once by the purchaser, and further offers a highly practical and easy grip due to the fact that the handle lip  36  projects vertically downwardly and does so along a significant distance. Furthermore, there is a convenient finger spacing  44  provided behind the handle lip  36 . These latter features are visible more clearly on  FIG. 4C . 
         [0020]    Turning now to  FIG. 3 , the details of the engagement portions  22 ,  24  which serve to cause the resilient effect which maintains the lid  14  closed against the receptacle  14  independently of the eventual removal of the barrier strip  26  are shown in greater detail. In fact, it will be seen in the details of this particular embodiment that the closure  40  of the lid  14  is parallel to the rim  38  of the lid  14 , but downwardly projects therefrom and is thus offset. The quasi-annular lid wall  18  which vertically interconnects the periphery of the lid closure  40  to the lid rim  38  is formed with a correspondingly quasi-annularly shaped outwardly protruding bulge referred to herein as an annular or peripheral engagement rib  50 . The lid closure  40  itself in this embodiment is relatively flat, but it nonetheless defines a slight camber oriented in the direction of the cavity  28 , the purpose of which will be detailed below. 
         [0021]    Looking now more particularly at the receptacle  12 , and still referring to  FIG. 3 , it can be appreciated that the upper wall portion  20  of the receptacle also has a quasi-annular bulge or engagement rib  52 , but which protrudes inwardly. The expression annular or quasi annular are used herein to refer to the fact that the given features surround the container  10 , independently of whether the container  10  is circular or not. It will be understood that the particular configuration of which is to be designed given the elasticity of the material(s) used, in a manner that the inwardly protruding engagement rib  52  of the receptacle  12  normally interferes with the shape and dimension of the rib  50  in the lid, but that at least one of the two components will resiliently yield to allow the rib  50  in the lid  14  to penetrate into the area underneath the inwardly protruding rib  52  of the receptacle wall portion  20  in a somewhat snapping resilient effect. This action can be seen more clearly by referring successively to  FIG. 4A  and  FIG. 4B . 
         [0022]    As shown in  FIG. 4B , once the lid  14  has been forced into the closed position, the lid  14 , and more particularly the closure  40  thereof, comes into abutment with an upwardly-oriented peripheral abutment  54  provided as part of the receptacle  12 . At this point, the rib  50  of the lid  14  is pressed against an engagement portion  56  of the receptacle wall portion  20  which is inclined so as to face both inwardly and downwardly. The force F exerted between the engagement portion  56  and the lid rib  50  thus both maintains the lid rib  50  pressed against the engagement portion  56 , but the vertical portion of the reaction to this force F also maintains the closure  40  pressed against the abutment  54 . In this particular configuration, the fact that the closure  40  is cambered contributes to this resilient effect and creation of the force F. Further, because the closure is cambered toward the cavity  28 , a pressure increase occurring in the cavity upon closing the lid will act against the closure  40 , tend to press upwardly against the camber and thus further push the annular lid rib  50  against the engagement portion  56  of the receptacle  12 , and thereby strengthen the lock and seal. A pressure increase typically occurs for instance as the lid is pushed closed against the receptacle, but can also occur in other circumstances, such as if liquid is shaken in the container, for instance. It will be noted here that in this particular embodiment, a gutter shaped member, or gutter  58 , is provided between the peripheral abutment  54  and the engagement portion  56 . It will be noted that the gutter is free from interference with the lid  14 , and that it can contribute to the resilient effect by acting in the manner of a spring biasing the engagement portion  56  inwardly. A form of spring can thus be said to be formed in the receptacle portion  12  by the “S” shape formed by the combination of the peripheral abutment  54  and the gutter  58 , given the elasticity of the plastic material, and a form of spring is formed in the lid portion with the camber in the closure  40 , the two springs working together to lock the lid in the closed position and form an effective seal. 
         [0023]    In certain applications where fluid matter is to be contained in the container  10 , it is desirable that an effective seal be provided between lid  14  and the receptacle  12  to prevent or at least limit the evacuation of fluid between the lid  14  and receptacle  12 . Positioning a rib made of the resilient plastic material in a manner that it be maintained in pressing contact with a flatter surface can allow to achieve a satisfactory seal in certain applications. In the particular configuration illustrated, the plastic container is designed with two distinct features where this occurs: firstly where the peripheral abutment  54  forming a rib is maintained pressed against the flatter surface of the closure  40 , and secondly, where the lid rib  50  is maintained pressed against the engagement portion  56  of the receptacle  12 . Both of these features can thus be designed to form an independent seal along the entire periphery of the container. The presence of two distinct seals, separated here by the gutter  58  for instance, can increase the sealing efficiency. Further, the efficiency of the seal can also be affected by the radius of the rib. The peripheral abutment  54  of the receptacle  12  can thus be referred to as the sealing rib of the receptacle  12 , whereas the peripheral rib  50  of the lid  14  acts as a sealing rib of the lid  14 . It will be understood that the presence of a gutter  58  is optional, and that if used, it can be oriented otherwise than downwardly in alternate embodiments, such as laterally for instance. 
         [0024]    It will be understood that the embodiment described herein and illustrated are provided for illustrative purposes only and that the improvements can be embodied in a wide variety of alternate embodiments or realizations. For instance, alternate embodiments can include plastic containers made with injection moulding, plastic containers having distinct/unconnected lid and receptacle, plastic containers not intended to be leak-resistant, or plastic containers without tamper-evident features. Where present, the hinge can alternately consist of a simple fold, for instance. Although the depicted container has an oval horizontal cross-section, it can have other closed curved shape, ranging from closer to a circle, to closer to a rectangle but without sharp corners, for instance. The wall portion, rims, ribs, handle lip and barrier strip can be shaped to correspond with the alternate shape of the horizontal cross-section. Further, it is to be understood that the expressions up and down, vertical and horizontal, etc. are used herein for convenience and typically refer to the container when it is laid flat on a horizontal surface. The expressions inwardly/outwardly refer to the inside of the container, and often refer to a horizontal or vertical orientation relative to the inside of the container. The expression vertical in particular must be interpreted with some breadth as encompassing features which are close to vertical. The expression oval can be interpreted rather loosely and can include an ellipse. It will also be understood that reference is often made to the container in its closed configuration to discuss sealing, engaging, and tamper-evident features, for instance. This thorough description provided for the convenience of the skilled reader is thus not intended to be interpreted in an unduly restrictive manner. 
         [0025]    As can be seen therefore, the examples described above and illustrated are intended to be exemplary only. The scope is indicated by the appended claims.