Abstract:
A container with lid, in particular a bucket with lid, has a container wall, a container bottom and a container opening, which is defined by an upper edge of the container, and structure in the upper part of the container for fixing the lid or a peripheral, inwardly protruding frame, to which the lid can be detachably locked. The container wall has on its upper part an outwardly protruding shoulder, such that containers can be stacked one into the other. To provide a container with lid which can be easily manufactured at low cost, if possible also by an in-mold labeling process, at least one radially outwardly and/or axially projecting protrusion ( 16, 30 ) is provided on a shoulder ( 12 ) on the outside thereof, wherein (a) an upper container rim ( 5 ) is provided with at least one recess ( 35 ), which when the containers are stacked one into the other is engaged by the at least one protrusion ( 30 ) of the shoulder ( 12 ) while preventing twisting, and/or wherein (b) the at least one axially projecting protrusion ( 16 ) extends at least around a part of the container ( 1 ) and radially outwardly engages behind an upper rim portion ( 5, 7 ) of a respective lower one of the stacked containers.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    This invention relates to a container with lid, in particular a bucket with lid, the container comprising a container wall, a container bottom and a container opening, which is defined by an upper edge of the container, and structure in the upper part of the container for fixing the lid or a peripheral, inwardly protruding frame to which the lid can be detachably locked. The container wall has on its upper part an outwardly protruding shoulder, such that the containers can be stacked one into the other. 
         [0002]    Various containers of this kind are known, and they can be dimensioned with a relatively large volume to store, for example, coating compounds, foodstuffs or the like. Such containers can have a capacity of ≧1-5 liters. The filled containers must not only be tight, they must also meet various other requirements. For instance, the containers should be producible by an in-mold labeling process, in which case the container should not have any inwardly protruding projections or fins, so that the container can be temporarily stabilized by a peripheral supporting device. Further, also the outer wall of the container should often be without protrusions. On the other hand, for the separation of the containers, for instance during the manufacturing process, means for securing the stacked containers against twisting are provided. Further, to save raw material, the containers should be as lightweight as possible, so that external peripheral flanges with a downwardly extended rim portion, as usually provided, should be avoided. But this entails a risk that containers which are stacked one into the other become wedged at larger stack heights, whereby the label on the outside is damaged or a separation of the containers is made more difficult. 
         [0003]    In most cases this risk cannot be removed even by the outwardly protruding shoulder, because this shoulder frequently protrudes only a relatively short distance. On the other hand, such a risk could be removed by employing stacking connectors arranged on the inside of the container and by limiting the nesting height of the containers. This, however, would make it more difficult or even impossible to carry out an in-mold labeling process. 
       BRIEF SUMMARY OF THE INVENTION 
       [0004]    The invention is therefore based on the objective of providing a container with lid which can be easily and inexpensively manufactured, if possible also by an in-mold labeling process. 
         [0005]    The container may have at least one recess in a peripheral rim that is provided in an upper part of the container. This recess is engaged by a protrusion provided on the outside of another container on a shoulder thereof, while being secured against twisting when the containers are stacked one into the other. This securing of the containers against becoming twisted relative to each other allows automatic separation of the containers while preventing in-mold labels, which may be provided on the outside of the container, from being damaged. The recess on the inner wall of the container is upwardly open. The recess can be formed as a break-through or a hollow of the container wall. This recess can also extend only over a part of the thickness of the container wall, thus being a kind of an inward bulging or impression, provided that this inward bulging or impression can be engaged by a protrusion axially projecting from the shoulder of a container to be nested, in a fashion secured against twisting. 
         [0006]    The peripheral rim provided on the upper part of the container can be the free upper edge of the container defining the container opening. Should the container have several peripheral shoulders in the form of a cascade-like, upwardly expanding container opening, so that several outwardly protruding shoulders with an increasing diameter are provided, the protrusion for instance which downwardly projects from the shoulder of the container on the outside thereof can engage in a recess of a peripheral rim that is formed by the container inner side of such a shoulder, if need be, in a fashion secured against twisting. 
         [0007]    Alternatively or additionally, the protrusion provided on the shoulder on the outside of the container and preferably axially projecting towards the bottom of the container can extend all around or at least around a part of the container and engage behind an upper rim on the respective lower one of the nested containers while preventing radial expansion. Here, too the upper rim of the container which is engaged from behind can constitute the upper edge of the container defining the container opening or can be formed by an additional shoulder, for instance in a case where a container has a cascade arrangement of shoulders. 
         [0008]    Thus, the container according to the invention can be particularly easily manufactured by an in-mold labeling process, without the risk of damaging the label, and because the containers are secured against twisting they can be securely prevented from becoming stuck one into the other, thus impeding separation thereof, even if the containers are heavy and the stacking height is large. Further, a container according to the invention may dispense with a peripheral flange having a rim portion extended downwardly towards the bottom of the container, which rim portion at least substantially extends vertically or slightly inclined to the main axis of the container and mainly serves to stabilize the container wall in the region of the container opening and/or to support a carrying handle. Such flanges are usually provided with radial reinforcement ribs connecting the vertically downwardly directed rim portion to the outside of the container. In such flanges the outer rim of the lid around the upper edge of the container extends downwards at least almost as far as to the flange. 
         [0009]    The protrusions of the container which are arranged on the outside of the container can also be molded to the container wall that extends vertically or is sloped downwardly to the bottom of the container. If need be, the protrusions can project radially outwardly over the shoulder. Preferably, they terminate flush with an outer edge of the shoulder or recede towards the container wall with respect to this outer edge. If need be, these protrusions can be slightly spaced from the container wall, even if this is not preferred. The protrusions can also be slightly spaced from the shoulder in the vertical direction and can be molded for instance to the downwardly sloping container wall. Preferably, they are molded to the bottom side of the shoulder. Preferably, the vertical distance of the protrusions to the shoulder, if provided at all, is less than the height of the protrusions themselves, ≦½ or ≦¼ of the height of the protrusion. 
         [0010]    The axial extension of the recess of the container rim receiving the anti-twist protrusions and/or the axial extension of the anti-twist protrusions themselves can be smaller than or equal to 4 to 8 times, smaller than or equal to 2 to 3 times or smaller than or equal to the single thickness of the container wall. The peripheral extension of the container rim and/or the anti-twist protrusions can be smaller than or equal to 15 to 20 times, smaller than or equal to 8 to 10 times, smaller than or equal to 4 to 6 times or smaller than or equal to 2 to 3 times or one time the thickness of the container wall. This can respectively apply to the thickness of the container wall directly above or below the shoulder. 
         [0011]    The shoulder can protrude radially outwardly from the container wall at an amount smaller than or equal to 8 to 10 container wall thicknesses, smaller than or equal to 4 to 6 or smaller than or equal to 2 to 3 or also smaller than or equal to one container wall thickness. This can apply to the thickness of the container wall directly above or below the shoulder, and this can also apply when the shoulder is constructed as a radially protruding fin. 
         [0012]    The at least one protrusion which projects axially from the shoulder towards the bottom of the container can have a height which is smaller than or equal to 5 times or smaller than or equal to 3 to 4 times, smaller than or equal to 1 to 2 times or smaller than or equal to 0.5 times the height of the radial extension of the shoulder. The height of the protrusion which projects axially from the shoulder towards the bottom of the container can also be smaller than or equal to 5 times or smaller than or equal to 3 to 4 times, smaller than or equal to 1 to 2 times or smaller than or equal to 0.5 times the thickness of the container wall directly above or below the shoulder. The radial thickness of the protrusion can be smaller than that of the container wall, e.g. smaller than or equal to ¾, smaller than or equal to ½ or smaller than or equal to ⅓ of the thickness of the container wall. 
         [0013]    The container can have articulation links on its wall, for holding a carrying handle, for instance in the form of radially protruding pins which are preferably attached directly to the wall of the container and not to a peripheral flange. In the region of the articulation links the wall of the container can have a greater wall thickness. The recesses for receiving the anti-twist protrusions and/or the anti-twist protrusions themselves can be arranged in the region of the articulation links. For instance, a recess and an associated anti-twist protrusion can be arranged directly above the articulation link. Also two such recesses and/or protrusions can be arranged on both sides of the articulation link, preferably at a short distance in the circumferential extension thereto. If need be, the recesses and/or anti-twist protrusions can be provided also in different circumferential regions of the container. 
         [0014]    The shoulder of the container wall can be so constructed that it requires a change of the cross section also on the inner side of the container, for instance in the form of a step, a radial offset or a change of the inclination of the inner wall of the container. If need be, the inner wall of the container can also be formed to be substantially continuous at the level of the shoulder. The shoulder may require an enlargement of the container inner radius of the container cross section above the shoulder compared to the container cross section below the shoulder. If need be, the shoulder can also be constructed as a fin of the outside wall of the container, which fin extends all around the periphery of the container or only around a part of the periphery of the container. Recesses for receiving the anti-twist protrusions can also be provided on a fin arranged on the outside of the container below the upper edge thereof. The peripheral fin can be at least substantially free from a vertically downwardly extending, downwardly drawn portion. A section of the fin which extends vertically downwardly from the bottom side of the fin can be smaller than or equal to 3 to 4 times, smaller than or equal to 1 to 2 times or smaller than or equal to 0.5 times the height of the fin portion molded to the wall. The height of the fin can be smaller than or equal to 3 to 5 times or smaller than or equal to 2 to 3 times the height of the recesses and/or the thickness of the wall of the container at the level of the fin. The radial extension of the fin can be smaller than or equal to 4 to 6 times, preferably smaller than or equal to 2 to 3 times or smaller than or equal to 1 time the height of the fin. 
         [0015]    The anti-twist protrusions can also be hook-shaped, for engaging in the recesses. The recesses can be generally constructed also in the form of two mutually spaced lateral stoppers. The anti-twist protrusions can be generally provided on the respective lower one of the stacked containers, and the recesses accommodating these protrusions can be provided on the respective upper one of the stacked containers. 
         [0016]    Preferably the outer wall of the container is free from protrusions, except of the projecting shoulder and/or the regions for supporting the carrying handle. 
         [0017]    The protrusions forming an anti-twist device and/or the protrusions partly preventing an axial expansion each can be provided with reinforcing parts. In particular, the protrusions forming an anti-twist device, which may generally extend substantially in the radial direction, and the protrusions which extend at least partly around the circumference of the container can be molded one to the other. The anti-twist protrusions can recede in height over protrusions engaging behind the rim of the container or they can terminate at least substantially flush with the same. 
         [0018]    It will be understood that also several protrusions can be provided which extend at least around a part of the periphery of the container and which are equally distributed over the periphery of the container. If need be, only one protrusion or rim can be provided running all around the container and extending from the protruding shoulder towards the bottom of the container. 
         [0019]    Preferably, the container is so constructed that the upper one of the nested containers is seated by its shoulder or peripheral fin on the container rim of the lower container, preferably on the free upper edge of the container defining the container opening. 
         [0020]    Preferably, the upper part of the container wall includes a radially inwardly and/or outwardly directed constriction by which a peripheral fin is formed on the upper container wall, which fin is set back from the outside and/or inside of the container. The at least one protrusion of a nested container, which extends all or at least partly around the container, can engage behind the fin on the external side. This avoids radial expansion during stacking the containers, even in the case of large stacking heights. At the same time the set back part of the upper wall of the container can completely or at least partly accommodate a downwardly extending continuous peripheral rim portion of the lid. The lid can terminate flush with the outside of the container. This correspondingly applies to a downwardly extending external peripheral rim portion of a frame to which a lid can be fixed. Accordingly, the fin can extend upwards, in particular at least substantially parallel or only slightly inclined to the main axis of the container, preferably in extension of the container wall. The inclination of the fin to the main axis of the container can be smaller than or equal to ±20° or ±10°. The upper edge of the fin can constitute the upper edge of the container. 
         [0021]    In particular, on the upper part of the container wall structure for fixing the lid and/or the lid-fixing frame can be provided, particularly in the form of a lock constructed as a radially protruding peripheral locking rim. In particular, these locks can be provided on a preferably upwardly extending fin molded to the upper part or upper rim of the container wall. The radial inside or outside of the fin can merge into the inner wall of the container continuously and preferably stepless or without offset. Thus the fixing or locking means provided on the fin can be arranged on the radial outside or on the radial inside of the fin. The fin preferably has a smaller radial wall thickness than the container wall. 
         [0022]    It will be understood that the anti-twist protrusions can generally engage in recesses of a shoulder or fin of an upper one of nested containers, i.e. “from below,” though an engagement “from above” is preferred. 
         [0023]    For stabilizing the upper part of the container, it is preferred for the container wall above the shoulder to become thicker towards the upper edge of the container. 
     
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
         [0024]    The foregoing summary, as well as the following detailed description of the invention, will be better understood when read in conjunction with the appended drawings. For the purpose of illustrating the invention, there are shown in the drawings embodiments which are presently preferred. It should be understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown. In the drawings: 
           [0025]      FIG. 1  is a cross-sectional view of a portion of a container with lid according to an embodiment of the invention; 
           [0026]      FIG. 2  is a partial cross-sectional view of nested containers according to  FIG. 1 ; 
           [0027]      FIG. 3  is a further partial cross-sectional view of nested containers according to  FIG. 1 ; 
           [0028]      FIG. 4  is a detailed lateral view of a container according to  FIG. 1 ; and 
           [0029]      FIGS. 5   a ,  5   b  and  6  are schematic cross-sectional, partial views of two further embodiments of containers according to the invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0030]    The container  1  according to one embodiment of the invention and illustrated in the  FIGS. 1 to 4  includes a container wall  2 , a container bottom  3  and a container opening  4 , which is defined by an upper rim  5  of the container wall. In the upper part  6  of the container wall, namely in this embodiment on the upper edge  7  of the container, fixing means  10  for fixing a lid or an inwardly protruding peripheral frame  8 , to which a lid  9  can be detachably fixed, are provided. The fixing means can be particularly constructed as a locking rim extending all around and, if need be, also as a number of locking protrusions distributed over the periphery of the container. The container wall  2  includes in its upper part below the fixing means an outwardly protruding shoulder  12 . This shoulder can be formed on the inner surface of the container also in the form of a step or a radial offset or, if need be, the inner wall of the container at this position can also be formed substantially continuous or so as to exhibit merely a change in its angle with respect to the container main axis  13 . However, the shoulder requires an enlargement of the container inner radius of the container cross section  15   a  above the shoulder compared to the container cross section  15   b  below the same. Further the containers are designed for being stacked one into the other, for which purpose the container wall may be conically tapering towards the bottom of the container, at least in the region below the protruding shoulder  12 . 
         [0031]    On or in the region of the shoulder  12  on the outer surface of the container at least one protrusion  16  axially projecting towards the container bottom  3  can be provided. According to the embodiment, this protrusion is formed as a radial rim extending all around, but it can also be provided in the form of two, three or a plurality of protrusions distributed over the container periphery. It may be sufficient for these protrusions to extend only around a part of the container periphery. With the containers stacked one into the other (see  FIG. 2 ) the protrusion  16  can radially outwardly engage behind an upper rim portion, which here constitutes the upper edge  7  of the container, while avoiding a radial expansion of the lower one,  1   b , of the stacked containers. Here the protrusion  16  is provided on the upper container  1   a . When the containers are stacked one into the other, the bottom side  17  of the shoulder  12  on the outside of the container can be generally seated on the upper edge  7  of the container, thus producing an annular abutment. The bottom side  17  of the shoulder can also be slightly spaced from the upper edge  7  of the container. 
         [0032]    Further, the container is so constructed that, when the containers are stacked one into the other, the outer wall  18  of the upper container  1   a  is only slightly radially spaced from the inner wall  19  of the lower container  1   b  at the level of the shoulder  12 , for instance ≦3 to 5 times, ≦1 to 2 times or ≦0.5 to 0.75 times the wall thickness of the lower container directly below and/or directly above the shoulder  12 . The outer wall  18  of the upper container  1   a  at the level of the shoulder  12  of the lower container  1   b  can also rest against the inner wall  19  of the lower container. This considerably increases the stability of the container stack. This can apply quite generally and independently of the embodiment. 
         [0033]    The upper part  20  of the container wall can have a radially inwardly directed constriction  21  forming a peripheral fin  22  set back from the outer surface  18  of the container. The fin can extend essentially axially, i.e. without or with only a small angle to the container main axis and, if need be, in axial extension of the container wall. The at least partly circumferential axial protrusion  16  can engage behind the fin  22  on its external side when the containers are stacked, so that the fin is fixed in the radial direction or prevented from a radial expansion by the protrusion. The protrusion can engage behind the fin with a certain minor play in the radial direction, for instance with a radial distance ≦1 to 2 times the container wall thickness, or it can rest against the outside of the fin substantially without force or under a certain biasing when the containers are stacked one into the other. 
         [0034]    The fin  22  has attached or molded to it fixing means  10 , which in the present case are constructed as locking means or more precisely as a circumferential locking rim. The fixing means  10  serve to fix a lid and/or a lid-fixing frame  8 . The fixing means can be arranged on or molded to the outside of the fin  22 , if need be, also to the inside. As shown by  FIG. 1 , the radially outside downwardly extended rim portion  26  of the frame or of the container can terminate flush with the outer wall of the container or can slightly protrude outwardly. The frame or lid may include an annular downwardly open groove  24 , which completely or at least partly accommodates the fin  22  and can be drawn downwards on the container wall as far as below the fin. 
         [0035]    The part  27  of the container wall above the shoulder  12  can increase in its wall thickness towards the upper edge  7  of the container, particularly towards the base of the fin  22 . The inner wall of the container above the shoulder  12  can be slightly inclined towards the container main axis  13 , i.e. radially inwardly. 
         [0036]    Further, according to the  FIGS. 3 and 4 , several protrusions  30 , in the present embodiment four protrusions  30 , neighboring each other are equally distributed over the periphery and are arranged on both sides of the articulation link  31  for fixing a handle  33 . The protrusions at least approximately define the reinforcement region  32  of the part of the container wall on which the respective articulation link is arranged, for instance in the form of a pin. In this embodiment the circumferential extension of these protrusions  30  substantially corresponds to the radial extension, but it can also be larger. Further (see  FIG. 3 ), the protrusions are molded to the outer wall  18  of the container on their side facing the center of the container. Here, the axial and/or circumferential extension of the protrusions  30  substantially corresponds to one or two times the wall thickness directly below or above the shoulder  12 . The protrusions  30  can also be constructed as strips that extend over a greater circumferential distance. 
         [0037]    The protrusions  30  have associated in the upper part of the container, in the embodiment on the upper edge  7  of the container, a corresponding or even higher number of recesses  35 , which are engaged by the protrusions while securing the containers against twisting when the containers are stacked one into the other. The circumferential extension of the recess can substantially correspond to that of the engaging protrusions  30  or can be larger than that. The axial depth of the recesses substantially corresponds to the height of the protrusions. The bottom side of the shoulder  12  can rest on the upper edge  7  of the container disposed thereunder. The lower edge of the protrusions can be slightly spaced from the lower edge of the recess or can also essentially be seated on this lower edge. The circumferential extension of the recesses  35  essentially corresponds to their axial extension or is slightly larger, as in the embodiment. Instead of the recesses which extend over the entire thickness of the container wall or instead of upwardly open breakthroughs also pocket-like recesses can be provided, which extend over a part of the thickness of the container wall or which are closed on one side or on both sides, as long as these recesses can receive the protrusions of the nested container, while securing this container against twisting. The anti-twisting engagement of the protrusions in the recesses considerably facilitates automatic separation of the containers. 
         [0038]    As illustrated by  FIG. 3 , the recesses can partly or almost fully break through the fixing means  10  constructed as a locking rim, but the locking rim can also be arranged below the recesses. The protrusion  16  can terminate with its bottom side or lower edge at least substantially flush with the bottom side of the protrusions  30  or can project axially towards the bottom with respect to the protrusions, so that the protrusions  30  can be covered in side view. The protrusions  30  can also project downwards with respect to the protrusion  16 . The protrusions  30  and the at least one or more protrusions  16  are molded to each other and merge into each other and are thus stabilized. 
         [0039]    The axial extension of the protrusions  16  and/or the protrusions  30  can be ≦3 to 4 times or ≦1 to 2 times the thickness of the container wall, independently of the embodiment, and approximately half the thickness of the container wall in the embodiment. 
         [0040]    The protrusion  16 , which preferably extends all around the periphery, can partly overlap the height of the fixing means attached to the fin of the upper rim of the container. This can apply independently of the embodiment. Further, the protrusion  16 , which is arranged on the shoulder and extends at least around a part of the periphery, can at least partly and preferably only partly overlap the fin provided on and upwardly protruding from the upper rim of the container and constricted with respect to the container, particularly in the upper part of the fin, where also the fixing means for a lid and/or frame can be arranged. 
         [0041]    The shoulder having the at least one protrusion arranged thereon, which preferably protrudes towards the bottom of the container, can also be generally constructed merely as a peripheral fin  50  of the outer wall of the container  51 .  FIGS. 5   a ,  5   b  show the container in various cross sections corresponding to the  FIGS. 2 ,  3 . The inner wall  52  of the container, at the level of a shoulder which is constructed in this way, can at least substantially be straight or continuous, without a shoulder or step or also without a change of the angle of inclination on the inside of the container. Here, the fin preferably extends essentially only outwardly in the radial direction, i.e., it does not have a downwardly extended rim portion, except of the protrusion  16 , which is molded to it and which extends in the axial direction. Here, too the fin preferably includes anti-twist protrusions  30  on its bottom side. These protrusions  30  can each engage in a recess  35  of an upper rim of the container, e.g., of the upper edge  7  of the container. Incidentally, what has been mentioned above also completely applies to forming the protrusions which extend around a part of the periphery and which prevent expansion and/or twisting. The axial extension of the fin having the at least one protrusion  16 ,  30  arranged thereon can correspond to that of the shoulder according to the embodiment illustrated in the  FIGS. 1 to 4 . It can be smaller than or equal to 5 to 10 times, smaller than or equal to 2 to 3 times or approximately 1 time the thickness of the container wall. 
         [0042]      FIG. 6  shows a schematic representation of a further embodiment in which the container  60  includes a cascade-like stepped outer wall having several, for example two, shoulders  61 ,  62 . Here, the upper and/or lower shoulder  61 ,  62  can be accompanied by an increasing cross section of the interior of the container, but this is not always absolutely required. 
         [0043]    On the outside of the container on the lower shoulder  62  a protrusion  65  is indicated, which axially projects towards the bottom  64  of the container and which fully or at least partly extends around the periphery. If several containers  60  are stacked one into the other, this protrusion  65  can engage a channel-shaped recess  66  provided on the upper rim of the container. The bottom side  69  of the shoulder  62  can be seated on or slightly spaced from the rim  67  of the channel-shaped recess  66 , for example by less than one to three times the thickness of the container wall. Further on the lower shoulder  62  a substantially radially extending projection  68  (schematically shown) is arranged, which can engage in a corresponding recess in the region of the upper shoulder  61 , for instance in a recess of the rim  67  of the channel-shaped recess  66  (illustrated by a broken line), so as to prevent twisting. The bottom side of the shoulder  62 , also in its construction as a radially protruding fin on the container wall, can extend substantially horizontally or also be inclined with respect to the main axis of the container, especially sloping downwards. Incidentally, what has been described above with regard to the embodiment according to  FIGS. 1 to 4  can also fully apply to the present embodiment in which the protrusions  65 ,  68  can correspond to the protrusions  16 ,  30 . 
         [0044]    It will be appreciated by those skilled in the art that changes could be made to the embodiments described above without departing from the broad inventive concept thereof. It is understood, therefore, that this invention is not limited to the particular embodiments disclosed, but it is intended to cover modifications within the spirit and scope of the present invention as defined by the appended claims.