Abstract:
A bag assembly comprises a plurality of members that are telescopically arranged inside one another, the members being transformable between an extended condition and a collapsed condition. The assembly has a substantially greater length in the extended condition than in the collapsed condition. In one arrangement, the bag assembly has an extended condition in which the telescopically engaging members extend upwardly and a flexible bag is disposed substantially within the interior space defined by the members. A lid is also provided. In another arrangement, the members are inserted into a bag, keeping the top of the bag open to assist filling of the bag.

Description:
TECHNICAL FIELD 
       [0001]    This invention relates to a bag assembly comprising a flexible bag and an assembly of telescoping members. It also relates to a method of filling a flexible bag. 
       BACKGROUND OF THE INVENTION 
       [0002]    In domestic situations it is very common practice to insert a flexible bin liner into a bin. The liner is then filled and, when full, removed from the bin. The removal of the liner can be problematic. Firstly, access to the upper portion of the liner is obstructed by the bin and access to any lower portions is impossible. Secondly, the liner once filled can resist being lifted out of the bin as a result of friction between the liner and the sides of the bin. As a result it is common to find that a bin liner is torn whilst being removed from a bin. 
         [0003]    It is an object of the first aspect of the invention to provide a bag assembly and method of filling a bag that overcomes at least in part the problems indicated above. 
         [0004]    In various situations and especially the construction industry, it is common to need to fill flexible bags which may have a capacity of the order of one cubic metre. When filling such bags problems can arise with the sides of the bag falling inwards and obstructing the opening in the top. 
         [0005]    It is an object of the second aspect of the invention to provide a bag assembly and method of filling a bag that overcomes at least in part the problem indicated above. 
       SUMMARY OF THE INVENTION 
       [0006]    According to a first aspect of the invention there is provided a bag assembly comprising a flexible bag and a plurality of members that are telescopically arranged inside one another, the members being transformable between an extended condition and a collapsed condition, the assembly having a substantially greater length in the extended condition than in the collapsed condition, the bag assembly having an extended condition in which the telescopically engaging members extend upwardly and the flexible bag is disposed substantially within the interior space defined by the members. 
         [0007]    Such a bag assembly is able, in its extended condition to support a flexible bag, which may be a bin liner, in a similar way to a domestic bin, for example for use in a kitchen, or in a larger version for use in place of a dustbin. When a user wishes to remove the bag, the members can be collapsed around the bag. Once collapsed, the bag is only held within the collapsed assembly in a bottom region and the upper portion of the bag is fully accessible. As a result the bag can be removed from the members much more easily. 
         [0008]    In an embodiment of the invention described below, there are three members. We have found that providing three members enables the length of the assembly in the collapsed condition to be much reduced from that when it is in the extended position, while not introducing a great many parts. It should be understood, however, that two or more than three members may be provided. 
         [0009]    The members are preferably able to be secured together in intermediate positions between fully extended and fully collapsed conditions. In that case a user can adjust the height and volume of the assembly in an extended condition to suit a particular situation. There may be a multiplicity of discrete intermediate positions or the height may be continuously variable. 
         [0010]    The members are preferably able to be secured together in a fully collapsed condition. 
         [0011]    The members may be able to be secured together by a post on one member projecting into a recess or opening in another member. 
         [0012]    The members may be able to be secured together by rotation of one member relative to another. 
         [0013]    The two optional features just described may both be employed by adopting a bayonet fastening arrangement. Furthermore by providing a bayonet fastening arrangement in which a projecting part on one member engages in a longitudinally extending groove in the other member and by providing transverse extensions to that groove along the length of the groove an adjustable bayonet fastening arrangement can be provided. 
         [0014]    Another possibility is for the members to be secured together by a generally dome-shaped protuberance on one member engaging in a recess or opening in another member. A plurality of recesses or openings are preferably provided in said another member at longitudinal spacings along said another member, with grooves extending between adjacent recesses or openings, and the generally dome-shaped protuberance on said one member is selectively engageable in the recesses or openings and is able to travel along said grooves between adjacent recesses or openings. The adjacent recesses or openings are preferably provided along a linear path substantially parallel to the longitudinal axis of the members. Such an arrangement provides an especially advantageous coupling between the members because it remains easy to adjust the degree of telescoping of the members but the members can be reliably held in engagement at a selected degree of telescoping. 
         [0015]    Preferably the members are able to be secured together by one or more discrete protuberances on one member frictionally engaging another member. The protuberances are preferably wedge-shaped. Preferably, they are provided close to an end region of one member for engaging another member when the members are in a collapsed condition. Such an arrangement provides a very simple method of holding members together in a collapsed condition. 
         [0016]    Whilst it is within the scope of the invention for there to be a single fastening arrangement between two telescopically engaging members, it is preferred that there are more. In an embodiment of the invention described below two diametrically opposite fastening arrangements are provided, but it is also possible to provide three, four or more arrangements, preferably equiangularly spaced around the members. 
         [0017]    The members may be able to be secured together by virtue of friction forces between adjacent faces of respective telescopically engaging members. Such a method of securing is advantageous in that it requires no additional parts. It may not, however, be sufficiently strong or reliable and consistent for some applications, especially for securing the members in an extended condition. Accordingly, the members may be securable at least partly by a fastener (for example the bayonet fastener or dome-shaped protuberance described above) which is engageable between at least two of the members. Such an alternative or additional fastening arrangement may be made as secure and reliable as the designer wishes. For example a fastening member may be mounted in one end of a telescoping member and able to make positive engagement with an opposite end of an adjacent telescopically engaging member. In a case where there are three members it may be convenient to provide two such fastening members. Alternatively or additionally the members may be securable in an extended condition by a protuberance which may interfere with the telescoping movement of one member relative to another. The protuberance may for example be provided on one member and engage an edge of another member when the members are in an extended condition. The arrangement may be such that in order to telescope the members together, it is necessary to deform one or both of them elastically. 
         [0018]    As described below with reference to a second aspect of the invention, the members may also be securable in a collapsed condition. They may be secured in the collapsed condition by any of the mechanisms described above for securing the members in an extended condition. 
         [0019]    Preferably the plurality of members are arranged such that they are not rotatable relative to one another about their axis. Especially if it is desired to be able to secure the members together in a collapsed or extended condition, it is useful if their relative rotational positions are substantially fixed, which may be achieved in a variety of ways. 
         [0020]    Whilst it is within the scope of the invention for the members to be of any of a wide variety of cross-sections, including rectangular or square cross-sections, it will usually be preferred that the members are of a generally round cross-section. The members may be of a circular cross-section or of a generally circular, but not an exactly circular, cross-section. An almost circular cross-section is advantageous in many cases for an interior shape but a degree of non-circularity may be advantageous for preventing relative rotation. For example the cross-section may be slightly oval; another possibility is to provide a longitudinal projection on a member engaging in a corresponding longitudinal groove of an adjacent member. Each member may be formed with a formation that provides a longitudinal projection on one face of the member and in a preferred embodiment of the invention, a longitudinal groove on an opposite face of the member. 
         [0021]    Preferably the members are rotatable relative to one another. 
         [0022]    The telescoping members may be of constant cross-section along their length but they may be of other varying cross-section. In an embodiment described below they are of generally frustoconical shape; in that case the smaller cross-section end of each frustoconical member is preferably its bottom end. 
         [0023]    In the case where the telescoping members are of generally frustoconical shape, the half angle of the cone defining the frustoconical members is preferably less than 10 degrees and more preferably less than five degrees; as will be understood a half angle of 10 degrees corresponds to a full cone angle of 20 degrees at the notional apex of the cone. The half angle of the cone is preferably sufficiently great that the members collapse easily, but in at least those cases where friction forces between the members are to be employed to retain the members in an extended condition, the half angle of the cone should not be too great. In an embodiment of the invention described below the half angle of the cone is about four degrees. 
         [0024]    The assembly may be made of any suitable material, in particular, but not exclusively, of metal or plastics material. In an embodiment of the invention described below the assembly is made of plastics material. 
         [0025]    The lower end of the assembly of members may be at least partially closed. In the case where the members are generally frustoconical, the smaller cross-section end is, in use, the bottom of the assembly and a partially closed bottom may support the bottom of a bin liner. The end may be fully closed; that has the advantage of retaining the contents of the interior of the assembly within the assembly even if, for example, the flexible bag tears. The full or partial closure may be effected by providing the innermost member with a bottom portion extending across its lower end. The bottom portion may be upwardly curved, at least in the region of the side(s) of the assembly, to smooth a transition from an approximately horizontal bottom portion to an approximately vertical side portion. Preferably there is a gradual and progressive increase in inclination from an approximately horizontal bottom portion to an approximately vertical side portion. The bottom portion may be of approximately hemispherical shape or some other curved shape that may be constant around a central vertical axis of the assembly. Such arrangements further facilitate removal of a bag. 
         [0026]    The assembly may further include a lid for closing over the upper end of the assembly. The larger cross-section end is, in use, the top of the assembly. The lid may include one or more handles. It may be a separate part from the assembly of members, or it may be connected, for example via a pivotal connection, to the assembly of members. In the latter case the lid is preferably connected to the outermost member in the region of its upper end. 
         [0027]    The larger cross-section end of the assembly may be arranged to receive the top of the flexible bag and may be provided with a particular arrangement or configuration for that purpose. 
         [0028]    The upper end of the assembly may be provided with a handle connected to its upper region. In an embodiment of the invention described below, a pair of handles are provided on opposite sides of an upper region of the uppermost member. 
         [0029]    The assembly of telescopically engaging members may be sold separately from the flexible bag with which they are used. Thus the first aspect of the invention is also directed to the members per se. Accordingly, in the first aspect of the invention there is provided a plurality of members that are telescopically arranged inside one another, the members being arranged for use in a bag assembly as defined above. The members may of course include any of the features defined above. 
         [0030]    According to the first aspect of the invention there is also provided a method of filling a flexible bag, the method including the following steps: 
         [0031]    providing a plurality of members that are telescopically arranged inside one another and can be transformed between an extended condition and a collapsed condition, the assembly having a substantially greater length in the extended condition than in the collapsed condition, 
         [0032]    extending the assembly of members to the extended condition with the members extending upwardly, 
         [0033]    placing a flexible bag with its top extending around the region of an open upper end of the assembly, 
         [0034]    adding material into the bag, 
         [0035]    collapsing the assembly of members away from their extended condition towards or into their collapsed condition, and 
         [0036]    lifting the bag upwardly out of the assembly of members. 
         [0037]    Once collapsed the bag is only held within the collapsed assembly in a bottom region and the upper portion of the bag is fully accessible. As a result the bag can be removed from the members much more easily. As will be understood, it may not be necessary to collapse the bag completely in order to facilitate the removal of the bag and therefore the collapsing step above may involve only partial collapse with the assembly of members not reaching their fully collapsed condition. 
         [0038]    The assembly of members may be securable in an extended condition by virtue of friction forces between adjacent faces of respective telescopically engaging members and/or by a fastener which engages two or more of the members. The assembly may also have any of the other features referred to above. 
         [0039]    In the collapsed condition of the assembly of members, the overall length of the assembly is preferably not more than 60%, and more preferably less than 40% of the overall length of the assembly in an extended condition. Additionally or alternatively, the overall length of the assembly is preferably not more than 150% of the average length of a member. 
         [0040]    In embodiments of the invention described below the overall length/height of the assembly is altered manually. Another possibility, however, is to provide a prime mover such as an electric motor with an appropriate electronic control system and appropriate drive train(s) to move the members relative to one another. If desired a remote control may be provided to allow a user to adjust the members remotely. 
         [0041]    According to a second aspect of the invention there is provided a bag assembly comprising a flexible bag, a plurality of members that are telescopically arranged inside one another and fastening means, the members being transformable between an extended condition and a collapsed condition, the assembly having a substantially greater length in the extended condition than in the collapsed condition, the bag assembly having an extended condition in which the members are disposed with at least a lower portion disposed substantially within the flexible bag, and having a collapsed condition in which they can be at least partially secured by the fastening means. 
         [0042]    The assembly of members is only intended to be used in the extended condition (although it can be used in the collapsed condition), but we have found that there is a substantial advantage in securing the members in a collapsed condition because it facilitates handling of the assembly when it is being moved or stored. The assembly may be used for filling relatively large flexible bags, for example those used in the construction industry. One end of the assembly may be arranged to receive the top of the flexible bag and may be provided with a particular arrangement or configuration for that purpose. 
         [0043]    The fastening means may comprise a fastener which is able to secure together the outermost and innermost members of the assembly in the collapsed condition of the assembly. It is not essential to secure any frustoconical members disposed between the innermost and outermost members because they may be retained by the securing of the innermost and outermost members, but it is within the scope of the invention to secure the other members and indeed that will often be advantageous, for example to prevent small movements of the other members. 
         [0044]    Preferably the assembly of members comprises a series of members in which each member flares outwardly in the same longitudinal direction so that the assembly of members, when in its extended condition, flares steadily outwardly from one end of the assembly of relatively small cross-section to an opposite end of relatively large cross-section. The assembly may be used with either the wider end or the narrower end at the top; generally, it will be preferred to use the assembly with the wider end at the top. 
         [0045]    According to the second aspect of the invention there is also provided a method of filling a flexible bag, the method including the following steps: 
         [0046]    providing a plurality of members that are telescopically arranged inside one another, the members being securable in both an extended condition and a collapsed condition, the assembly having a substantially greater length in the extended condition than in the collapsed condition, 
         [0047]    placing the assembly of members in the bag in the extended condition with the longitudinal axis of the members extending upwardly to an open end which is the wider end of the assembly, 
         [0048]    adding material to the bag through the open end of the members, 
         [0049]    lifting the assembly of members out of the bag, 
         [0050]    collapsing the assembly of members into the collapsed condition, and 
         [0051]    securing the assembly of members in the collapsed condition. 
         [0052]    The method may further include, after the step of adding material to the bag through the open end of the members and before the step of lifting the assembly of members out of the bag, the steps of: 
         [0053]    lifting the assembly of members at least partly out of the bag, and 
         [0054]    adding further material to the bag through the open end of the members. 
         [0055]    The assembly of members is preferably used with the wider end of the assembly as the upper end and the narrower end in the bag to be filled, since this makes the end through which material is delivered to the bag the wider end, but it is possible to use the assembly the other way up. 
         [0056]    In the description above, the first aspect of the invention relates to placing a bag in the assembly of members, while the second aspect of the invention relates to placing the assembly of members in a bag. It is possible for the same assembly of members to be used in both aspects of the invention. Thus a method of the first aspect of the invention may also include placing the assembly of members in a flexible bag in the extended condition, adding material to the bag through the open end of the members, and lifting the assembly of members out of the bag. 
         [0057]    The assembly of members employed in either aspect of the invention may include one or more accessories, either incorporated into the assembly or provided as an additional component. For example, the bottom of the assembly may be provided with a sieve; when used in the second aspect of the invention, the sieving would occur principally as the assembly was lifted upwardly. If the same assembly were used in the first aspect of the invention the sieve would provide a partially closed bottom on which a bin liner would rest. 
         [0058]    It will be appreciated that the various aspects of the invention as described herein are closely related and that therefore essential or preferred features of one aspect of the invention may, unless indicated otherwise or clearly inappropriate, be incorporated into other aspects of the invention as described herein. For example the apparatus according to the second aspect of the invention may employ members that are of constant cross-section along their lengths or of frustoconical shapes. It may also employ any of the fastening arrangements described with respect to the first aspect of the invention, including for example the bayonet fastening arrangement, the dome-shaped protuberance or the wedge-shaped protuberance. Also, any aspect of the method of the invention may use an apparatus according to the same, or any other, aspect of the invention. Similarly, an apparatus according to any aspect of the invention may be so configured as to be suitable for use in a method according to the same, or any other, aspect of the invention. Features of the apparatus of the invention may be incorporated into the method of the invention and vice versa. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0059]    By way of example embodiments of the invention will now be described with reference to the accompanying schematic drawings, of which: 
           [0060]      FIG. 1  is an isometric view from the side and above of a collapsible bin assembly comprising three frustoconical members and a lid, the assembly being shown in an extended condition, 
           [0061]      FIG. 2  is an isometric view of the lid, 
           [0062]      FIG. 3  is an isometric view from the side and below of the assembly of frustoconical members, the assembly being shown in a collapsed condition, 
           [0063]      FIG. 4  is an isometric view of a fastening member, 
           [0064]      FIG. 5  is an isometric view from the side and above of the bin assembly in a collapsed condition with the lid removed and with a bin liner received within the assembly, 
           [0065]      FIG. 6A  is an isometric view from the side and above of the assembly of frustoconical members being employed to fill a sack that is empty, 
           [0066]      FIG. 6B  is an isometric view from the side and above of the assembly of  FIG. 6A  at a later stage in the filling of the sack, 
           [0067]      FIG. 7  is a section through a part of the side wall of the bin assembly when the assembly is in an extended condition, 
           [0068]      FIG. 8  is an isometric, partly exploded, view from the front and above of a modified form of collapsible bin assembly, the assembly being shown in an extended condition, 
           [0069]      FIG. 9  is an isometric view from the side and above of a middle telescoping member of the assembly of  FIG. 8 , 
           [0070]      FIG. 10  is an isometric view from the front and above of a half section of an innermost member of the assembly of  FIG. 8 , 
           [0071]      FIG. 11  is an isometric view from the front and above of the assembly of  FIG. 8 , showing the assembly in a collapsed condition, 
           [0072]      FIG. 12  is a side view of a modified form of the assembly shown in  FIGS. 6A and 6B , with the members shown in a collapsed condition, 
           [0073]      FIG. 13A  is a sectional side view of an alternative fastening arrangement for securing two telescoping members together in selected positions, and 
           [0074]      FIG. 13B  is a diagrammatic front view of the part of the fastening arrangement of  FIG. 13A  that is provided on one of the members. 
       
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
       [0075]      FIGS. 1 to 3  show a bin assembly comprising an outermost frustoconical member  1 , a middle frustoconical member  2  and an innermost frustoconical member  3 , and, mounted over the top of the frustoconical member  1 , a lid  4  which in the embodiment shown has a handle  5 . In the particular example described, all the parts are made of plastics material. In the embodiment shown, the handle  5  is mounted centrally on the lid  4  and the lid  4  can simply be lifted off the top of the member  1 . A pair of handles  6  are provided on diametrically opposite sides of the top of the member  1 . 
         [0076]    Each of the members  1 ,  2  and  3  is of almost circular cross-section but with a small degree of eccentricity. The members fit closely inside one another each having a slightly wider top end than bottom end. The side walls are inclined at about four degrees to the vertical. As can be seen in  FIG. 3 , the members are dimensioned such that they can nest inside one another in a collapsed condition. In this collapsed condition, the exterior dimensions of the innermost member  3  are a little smaller than the interior dimensions of the middle member  2 , whose exterior dimensions are in turn a little smaller than the interior dimensions of the outermost member  1 . Also, the members  1 ,  2  and  3  are dimensioned such that when the assembly is extended to the position shown in  FIG. 1 , the exterior upper region of the innermost member  3  bears against the interior lower region of the middle member  2 , and the exterior upper region of the middle member  2  bears against the interior lower region of the outermost member  1 . Those forces result in sufficient friction to hold the members  1 ,  2  and  3  in the position shown unless a substantial force is applied. 
         [0077]    All of the members  1 ,  2  and  3  are tapered, flaring outwardly towards their upper ends. The top of the innermost member  3  is unable to pass through the bottom of the middle member  2  and, similarly, the top of the middle member  2  is unable to pass through the bottom of the outermost member  1 . 
         [0078]    A fastening member  7  is shown in  FIGS. 1 ,  3  and  4  for securing the members  1 ,  2  and  3  together in both a collapsed condition and an extended condition. The fastening member  7  has a head  9 , a shaft  9 A and a latch  10  all formed integrally with one another. The member  7  is rotatably mounted on the outermost member  1  and in one rotational orientation, the latch  10  is able to pass through oblong holes  8  in the lower portions of the members  2  and  3 . When the members are in the collapsed condition shown in  FIG. 3 , the latch  10  of the fastening member  7  can be inserted through the holes  8  and then rotated through one quarter of a full rotation to hold all the members  1 ,  2  and  3  together in a collapsed condition as shown in  FIG. 3 . If desired, in the extended condition of the members, a further fastening member  7 A (not shown) may be provided, mounted on a lower region of the middle member and engageable with an oblong hole (not visible in the drawings)in an upper region of the innermost member  3 . The middle member  2  may also be provided with an oblong hole in its upper region and that hole may be engaged by the fastening member  7  to securely lock the assembly in its extended condition. In addition (or as an alternative) to the fastener  7 A protruding domes  16  may be formed on the exterior of the members  2  and  3  towards their upper ends in order to retain the assembly in its extended condition.  FIG. 7  shows how the bottom edge of member  2  rests on the top of the dome  16 , but can be pushed over the dome by a downward force on the member  2 , with elastic deformation of the members  2  and  3  allowing the passage of member  2  over the dome  16 . 
         [0079]    A recess  15  is formed in the bottom of the lowest member  3 . A user may place a foot in the recess to hold the assembly on the floor while lifting the assembly upwards into its extended position. 
         [0080]    The assembly described above can be used in a variety of ways. Two especially advantageous uses are described below. 
         [0081]    Referring first to  FIG. 5 , a stage in the removal of a bin liner from the interior of the bin is shown. Previously a bin liner  11  has been fitted around the top of the outermost frustoconical member  1  with the assembly secured in its extended position and the bin liner has been filled with waste material. Once the bin liner  11  is full and it is therefore desired to lift the liner out of the assembly, the lid  4  is removed, the securing of the members  1 ,  2  and  3  in their extended position is released by rotating and withdrawing the fastening members  7  and  7 A and a user then presses downwardly on the top of the periphery of the outermost frustoconical member  1  collapsing the assembly around the bin liner and arriving at the state shown schematically in  FIG. 5  with more than half of the bin liner  11  projecting out of the top of the assembly. In this state the whole of the upper portion of the bin liner  11  is exposed, making it easy to close the top of the liner if desired. Also the liner  11  can readily be lifted out of the bin assembly both because it can if necessary be held around the middle, rather than only at the top and because there is a much smaller area of contact between the sides of the bin assembly and the liner because the members  1  and  2  do not make any contact. 
         [0082]    After the bin liner has been lifted out, the bin assembly can be returned to its extended condition, locked in that condition by the fastening members  7  and  7 A and a new bin liner fitted inside the assembly with the top of the liner engaging around the top of the outermost frustoconical member  1 , and the lid  4  can then be placed on top of the assembly. 
         [0083]      FIGS. 6A and 6B  illustrate a second advantageous use of the assembly of frustoconical members, with the lid  4  removed. In this case the assembly is inserted inside a flexible bag  12  and used to assist filling of the bag. A user first adjusts the assembly to its extended position and, if desired, locks it in that position using the fastening members  7  and  7 A ( 7 A not being shown). The user then holds the top of the bag  12  open and inserts the assembly in an upright orientation with the wider end of the assembly at the top. The user then has both hands free to load material (for example, sand gravel or rubble) into the assembly and there is no risk of the sides of the bag  12  obstructing the opening into the assembly since the top of the assembly is above the top of the sides of the bag. In due course the assembly becomes fairly full of the material and this is the condition shown schematically in  FIG. 6A . At that stage a user lifts the assembly away from the bottom of the bag  12 , allowing the material in the assembly to fall out of the assembly into the bag. The user then places the assembly on top of the material in the bag  12  and again fills the assembly.  FIG. 6B  shows the condition of the bag and assembly towards the end of this second filling process. The sequence of lifting the assembly to allow material in the assembly to fall out into the bag  12  can be repeated several more times until the bag is almost full. 
         [0084]    When the assembly is not in use, it can be collapsed to the condition shown in  FIG. 3  and locked in that condition by the fastening member  7 . That makes storage of the assembly much simpler. 
         [0085]    In the examples described above, the same assembly of frustoconical members is used in both the application shown in  FIG. 5  and the application shown in  FIGS. 6A and 6B . It should be understood that an alternative is to provide an assembly dedicated to each of the applications. If an assembly is being provided specifically for the application shown in  FIG. 5 , it may be preferred to provide the innermost member  3  with a closed base. If an assembly is being provided specifically for the application shown in  FIGS. 6A and 6B , it may be preferred to omit the fastening member  7 A and the lid  4 . 
         [0086]      FIGS. 8 to 11  show a bin assembly similar in various respects to the assembly shown in  FIGS. 1 to 5  but with some significant modifications. The assembly shown in  FIGS. 8 to 11  will now be described. It generally comprises a bottom, innermost, member  101 , a middle member  102 , an upper, outermost, member  103  and a lid member  104 . The members  101 ,  102  and  103  are all of generally circular cylindrical shape and telescopically engage one another. 
         [0087]    Referring especially to  FIG. 10 , the bottom, innermost, member  101  comprises a cylindrical sidewall  106 , and a curved bottom  107 . The bottom  107  is of approximately part-spherical shape as shown in  FIG. 10 , but, if desired, the curvature of the bottom  107  may be sharper than shown in  FIG. 10  so as to provide a smoother transition from the bottom  107  to the sidewall  106 . Providing such a curved bottom is useful in facilitating removal of a bag from within the member  101  and makes it easier to clean the inside of the member  101 . The member  101  is also provided with a pair of laterally projecting feet  108 . A user can place their own feet on the top of the feet  108  when removing a bag or when extending the bin assembly, to keep the member  101  on the ground. As an alternative to providing feet  108 , the member  101  may be provided with an outwardly extending rim or flange around its bottom for the same purpose. 
         [0088]    Referring especially to  FIG. 9 , the middle member  102  has a generally cylindrical wall  111  on the outside of which, towards the top, are a pair of short outwardly projecting posts  112 , of which one is only just visible in  FIG. 9 . On the inside of the cylindrical wall  111 , in the same circumferential region as each of the posts, are a pair of plates  113  which each carry a vertical groove  114  from which four transverse grooves  115  extend. Each of the transverse grooves  115  is formed with a short upward extension  116  at its end. In  FIG. 9 , only one of the plates  113  can be seen fully but it will be understood that both plates  113  are of the same design. 
         [0089]    The sidewall  106  of the bottom member  101  is also provided with a pair of posts  112  on the outside towards the top, one of the posts  112  being just visible in  FIG. 10 . The posts  112  on the member  101  engage in the grooves  114  on the member  102  to provide two bayonet fastening arrangements between the members. When the posts  112  on the member  101  engage the lowermost transverse grooves  115  on the member  102 , the members  101  and  102  are extended to the maximum extent, and when the posts  112  sit at the uppermost ends of the grooves  114  the members  101  and  102  are telescoped to the maximum extent. The other three grooves  115  in each plate  113  define three intermediate degrees of telescoping of the members  101  and  102 . 
         [0090]    The upper, outermost, member  103  is also provided with plates  113 , the tops of which are just visible in  FIG. 8 . The member  103  is of circular cylindrical shape and fits over the middle member  102 , with the posts  112  at the top of the middle member  102  engaging the grooves  114 ,  115  in the plates  113  on the member  103  to provide the same kind of fastening arrangement between the members  103  and  102  as is provided between the members  102  and  101 . A pair of handles  121  are provided on the exterior of the member  103  in an upper region of the member. The lid member  104 , which may be of any appropriate design, fits over and rests on the top of the member  103 . 
         [0091]    As will now be understood, the assembly can be placed in a wide variety of conditions between the fully extended condition shown in  FIG. 8  and the fully collapsed condition shown in  FIG. 11 . Starting from the condition shown in  FIG. 11 , in which the posts  112  are disposed at the top ends of the grooves  114 , the member  103  may be lifted by a user using the handles  121  and with their feet placed over the feet  108 . At a chosen degree of extension the member  102  can be rotated relative to the member  101  and the member  103  rotated relative to the member  102  to cause the posts  112  to enter respective transverse grooves  115 . After that rotation the user can let go of the handles  121  causing the members  102  and  103  to drop slightly as the posts  112  enter the extensions  116  of the grooves. In that condition the assembly is stably fastened at a selected degree of extension. In order to change the degree of extension, it is merely necessary for a user to lift a member slightly to move the parts  112  out of the extensions  116  and rotate the member back to the fully collapsed rotational position in which the posts  112  are in the vertical grooves  114 . The member can then be adjusted upwardly or downwardly and then rotated again to cause the posts to enter other transverse grooves  115 . 
         [0092]      FIG. 12  shows certain modifications that can be made to the assembly of members shown in  FIGS. 6A and 6B  and that is particularly, but not exclusively useful for filling bags as described with reference to  FIGS. 6A  and  6 B. The modified assembly differs from that shown in  FIGS. 6A and 6B  in the following respects: firstly, the members  1 ,  2  and  3  are of cylindrical shape; secondly, wedge-shaped protuberances  22  are provided at diametrically opposite locations on the insides of the members  1  and  2  near the top, so that when the members are in a fully collapsed condition the tops of the members are resiliently deformed and held in position relative to one another by friction; thirdly, a pair of diametrically opposite bayonet fastening arrangements each of the kind described above with reference to  FIG. 9  is provided for fastening the three members in a fully extended condition. As can be seen in  FIG. 12 , each bayonet fastening arrangement comprises a vertical groove  114  on each of the members  1  and  2 , from which just one transverse groove  115  extends with a short upward extension  116  at its end. The members  2  and  3  are each provided with a pair of diametrically opposite posts  112  on their outsides towards their top ends, the posts  112  engaging in the grooves  114 . If desired the top of the member  1  may be provide with a pair of handles. 
         [0093]      FIGS. 13A and 13B  show an alternative fastening arrangement to the bayonet arrangement shown in  FIGS. 9 and 12 . The arrangement is shown fastening a first telescoping member  201  to a second telescoping member  202 , with just the adjacent walls of the members shown in section in  FIG. 13A  and only the part of the fastening arrangement on the member  201  shown in  FIG. 13B . The member  202  has a single dome-shaped protuberance  203  projecting outwardly at its upper end from its main cylindrical wall  204 . The member  201  has an adjacent cylindrical wall  205  on which a fastener  206  is mounted. The fastener  206  is formed with a series of cup-shaped recesses  207  matched to the shape of the protuberance  203 . The recesses  207  are disposed along a vertical path and are connected by grooves  208 , the bottoms of which are indicated by lines in  FIG. 13A , from which it can be seen that the recesses  207  are deeper than the grooves  208 . The fastening arrangement shown in  FIGS. 13A and 13B  is provided at diametrically opposite positions of the members  201 ,  202  and, as will be understood the members are able to be resiliently deformed to allow the protruberance  203  to move out of a recess  207  along a groove  208  and into another recess  207 . 
         [0094]    Where in the foregoing description, integers or elements are mentioned which have known, obvious or foreseeable equivalents, then such equivalents are herein incorporated as if individually set forth. Reference should be made to the claims for determining the true scope of the present invention, which should be construed so as to encompass any such equivalents. It will also be appreciated by the reader that integers or features of the invention that are described as preferable, advantageous, convenient or the like are optional and do not limit the scope of the independent claims.