Patent Publication Number: US-11382404-B2

Title: Rucksack frame

Description:
BACKGROUND 
     This invention relates to a frame for a rucksack that is convertible into a support for a person such as a chair or bed. This invention further relates to a rucksack including such a frame. 
     When a person goes camping it is common to carry a tent, sleeping bag and other items in a rucksack that is carried on the person&#39;s back. In order to provide a more comfortable surface on which to sleep it is known to carry a roll up foam mat that can be placed on the ground under a sleeping bag. These mats are generally light weight. However, they are relatively bulky and either occupy a large portion of the internal space of a rucksack or have to be strapped to the outside of the rucksack. Furthermore, due to the limited weight of the camping mat and the placement of the mat directly on the ground or on a groundsheet, they only offer limited comfort. 
     Improved comfort may be provided by a camp bed which comprises a flexible support suspended from a frame. The frame is raised off the ground and supported on a plurality of legs. Because a person lying on the camp bed is raised off the ground, the camp bed provides improved comfort over a camping mat. A camp bed is, however, significantly heavier and larger than a camping mat. A camp bed is, therefore, not suitable for carrying in a rucksack. In particular, the dimensions of a camp bed, even when folded, make the camp bed awkward to carry as the camp bed is significantly wider than a traditional rucksack. 
     In other circumstances it is known to carry a foldable chair or sun lounger to an outdoor leisure site such as a picnic area or a beach. The chair or sun lounger will typically fold into a relatively flat configuration for transportation and storage. As with the camp bed, even in this folded configuration the chair or sun lounger is relatively bulky with relatively large dimensions. Accordingly, the chair or sun lounger is often simply carried in a person&#39;s hand or under their arm, rather than being carried in a bag. It is known to provide a strap to enable a person to carry the chair over their shoulder; however, the chair is still awkward to carry. 
     It is an object of the present invention to provide a support for a person, such as a chair or bed, that is more easily transported to a place of use. 
     SUMMARY OF THE INVENTION 
     According to a first aspect of the present invention there is provided a convertible frame for a rucksack, the frame being convertible into a support for a person and comprising:
         two main frame members connected together by a pair of extendable connectors;   at least two leg members connected or connectable to the main frame members; and   a flexible support attached or attachable to the main frame members to extend between the main frame members,   the frame being convertible between a first configuration, in which the main frame members have a first distance between them and the first distance defines a width of the rucksack, and a second configuration, in which the main frame members have a second distance between them and in which the main frame members are supported in a raised position by the leg members, and in the second configuration the main frame members suspend the flexible support for supporting the weight of a person when the main frame members are in the raised position, and wherein the second distance is larger than the first distance.       

     The first distance is preferably between 400 mm and 500 mm, and more preferably the first distance is about 450 mm. The second distance is preferably between 600 mm and 700 mm, and more preferably the second distance is about 620 mm. 
     In preferred embodiments the two main frame members extend parallel to each other. 
     Preferably each of the leg members is substantially U-shaped and comprises a base portion and two side portions. The base portion of each leg member may comprise one of the pair of extendable connectors. Each of the extendable connectors preferably comprises a pair of telescopic tubes and a sleeve surrounding a connection between said tubes. 
     In preferred embodiments each of the extendable connectors comprises a pair of members that are slidably engaged with each other. Each of the extendable connectors may comprise a pair of telescopic tubular members. 
     Preferably the leg members are connected to the main frame members and an angle between each of the leg members and the main frame members is fixed. 
     The support for a person may be in the form of a chair or bed. The flexible support may comprise a sheet of fabric. In other embodiments the flexible support may comprise a polymeric sheet. In further embodiments the flexible support comprises a plurality of flexible strips. 
     In some embodiments the convertible frame further comprises a latching mechanism configured to latch the convertible frame in the second configuration. The convertible frame may comprise a latching mechanism configured to latch the convertible frame in the first configuration. The latching mechanism preferably comprises a pin receivable in a hole or slot. The or each latching mechanism may comprise a retractable pin receivable in a hole or one of a plurality of holes. In embodiments in which the extendable connectors comprise a pair of members that are slidably engaged with each other, the retractable pin is preferably connected to a first one of the pair of members and the hole or the plurality of holes is preferably provided in a second one of the pair of members. 
     In some embodiments the convertible frame further comprises a foot frame connected or connectable to a first end of each of the main frame members, the foot frame comprising a pair of side frame members and a pair of legs, and the legs supporting the side frame members in a raised position when the convertible frame is in the second configuration. Each of the legs is preferably pivotally connected to a respective one of the side frame members. The side frame members of the foot frame may be pivotally connected to the main frame members. 
     In some embodiments the convertible frame further comprises a back frame connected or connectable to a second end of each of the main frame members, the back frame comprising a pair of side frame members and a pair of struts, and the struts supporting the side frame members at an angle to the main frame members when the convertible frame is in the second configuration. Each of the struts preferably extends between one of the side frame members and a leg member of the convertible frame. Each of the struts may be connectable to a respective one of the side frame members in a plurality of positions. Each of the struts is preferably pivotally connected to a respective one of the side frame members. The side frame members of the back frame may be pivotally connected to the main frame members. 
     In embodiments in which the convertible frame comprises a foot frame connected or connectable to a first end of each of the main frame members and a back frame connected or connectable to a second end of each of the main frame members, the flexible support preferably comprises a central portion that extends between the main frame members, a head portion configured to extend between the side frame members of the back frame and a foot portion configured to extend between the side frame members of the foot frame. 
     In preferred embodiments the head portion includes clips for securing the head portion to the side frame members of the back frame and the foot portion includes clips for securing the foot portion to the side frame members of the foot frame. Each of the clips preferably comprises an elongate resilient tubular member for engagement with the side frame member. 
     According to a second aspect of the present invention there is provided a rucksack comprising:
         a convertible frame according to the first aspect of the invention; and   a bag attached to the convertible frame, the bag defining an internal volume for holding contents of the rucksack.       

     The bag preferably comprises a sleeve for receiving a part of one of the leg members of the convertible frame such that the bag is suspended from the convertible frame by the sleeve. 
     In preferred embodiments the rucksack comprises shoulder straps for carrying the rucksack on a person&#39;s back. The convertible frame is preferably at least partially disposed between a rear panel of the bag and the shoulder straps. The bag may comprise a rear cover, and at least a part of the convertible frame may be disposed between the rear panel of the bag and the rear cover, with the shoulder straps connected to the rear cover. Preferably the main frame members and the flexible support are disposed between the rear panel of the bag and the rear cover. 
     In preferred embodiments a first part of the convertible frame is disposed between a first portion of the rear cover and a base of the bag, a second part of the convertible frame is disposed between a second portion of the rear cover and the rear panel of the bag, and a third part of the convertible frame is disposed between a third portion of the rear cover and a top of the bag. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will now be further described by way of example only and with reference to the accompanying drawings, in which: 
         FIG. 1  is a perspective view from the front of a first embodiment of a rucksack including a frame according to a first preferred embodiment of the present invention, the frame being in a first configuration; 
         FIG. 2  is a side view of the rucksack of  FIG. 1  showing the position of the frame relative to straps and an interior volume of the rucksack; 
         FIG. 3  is a perspective view from the rear of the rucksack of  FIG. 1  showing a rear flap and a top flap in an open configuration to allow access to the frame; 
         FIG. 4  shows the frame of  FIG. 1  in a second configuration and forming part of a sun lounger or bed, with a flexible support in a partially unfolded configuration; 
         FIG. 5  shows the frame of  FIG. 4 , with dashed lines indicating the position of the flexible support in a fully unfolded configuration and attached to a back frame and a foot frame of the sun lounger; 
         FIG. 6  shows the back frame of  FIG. 5 ; 
         FIG. 7  shows the frame for the rucksack of  FIG. 1  in its second configuration; 
         FIG. 8  shows the foot frame of  FIG. 5 ; 
         FIG. 9  shows part of a further embodiment of a frame in its second configuration; 
         FIG. 10  is a perspective view of a second embodiment of a rucksack including a frame according to a second preferred embodiment of the present invention; 
         FIG. 11  shows the rucksack of  FIG. 10  with a top flap of the rucksack opened to provide access to the frame; 
         FIG. 12  shows the rucksack of  FIG. 11  with a rear flap of the rucksack in a first partially open configuration; 
         FIG. 13  shows the rucksack of  FIG. 12  with the rear flap of the rucksack in a second partially open configuration; 
         FIG. 14  shows the rucksack of  FIG. 13  with the rear flap of the rucksack in an open configuration and showing the location of the frame in the rucksack, the frame being in a first configuration; 
         FIG. 15  shows the rucksack of  FIG. 14  with the frame removed from the rucksack; 
         FIG. 16  shows the frame of  FIG. 14  in the first configuration; 
         FIG. 17  shows the frame of  FIG. 14  in the first configuration; 
         FIG. 18  shows the frame of  FIG. 17  in a second configuration and forming part of a sun lounger or bed, with a flexible support in a partially unfolded configuration; 
         FIGS. 19 a  and 19 b    show a securement member for securing a part of the flexible support of  FIG. 18  to the frame; 
         FIG. 20  is a perspective view of a rucksack according to a third preferred embodiment of the present invention; 
         FIG. 21  is a front view of the rucksack of  FIG. 20 ; 
         FIG. 22  is a view of the rucksack of  FIG. 20  showing side pockets of the rucksack in an open configuration; 
         FIG. 23  is a perspective view of the rucksack of  FIG. 20  showing front pockets of the rucksack in an open configuration, and with a storage pod removed from a lower one of the front pockets; 
         FIG. 24  is a front view of the rucksack of  FIG. 20  showing front pockets of the rucksack in an open configuration; and 
         FIG. 25  is a rear view of the rucksack of  FIG. 20 . 
     
    
    
     DETAILED DESCRIPTION 
     The accompanying  FIGS. 1 to 8  show a convertible frame  10  according to a first embodiment of the present invention. The frame  10  is convertible between a first configuration in which the frame  10  forms part of a rucksack  12 , and a second configuration in which the frame  10  forms part of a support  14  for a person, such as a chair or bed. Advantageously, the convertible frame  10  has a first width in the first configuration so that the rucksack  12  is easy and practical to carry and a second width in the second configuration so that the support  14  has sufficient width to form a comfortable chair or bed. 
     The convertible frame  10  includes two main frame members  16 . The main frame members  16  are elongate; each extending between first and second ends  18 ,  20 . In this embodiment the main frame members  16  extend parallel to each other in a side by side arrangement with a distance or spacing between them. Preferably the first ends  18  of the main frame members  16  are aligned with each other and the second ends  20  of the main frame members  16  are aligned with each other. The main frame members  16  are connected together by a pair of extendable connectors  22 . The extendable connectors  22  are moveable between a collapsed or retracted configuration and an extended configuration, and movement of the extendable connectors  22  varies a distance between the main frame members  16 . In particular, with the extendable connectors  22  in the retracted configuration there is a first distance between the main frame members  16  and with the extendable connectors  22  in the extended configuration there is a second distance between the main frame members  16 ; the second distance being larger than the first distance. 
     Each extendable connector  22  preferably comprises a pair of tubular members  24 ,  26  slidingly connected to each other; relative sliding of the tubular members  24 ,  26  increasing or decreasing a length of the extendable connector  22 . The extendable connectors  22  may be telescopic. 
     The convertible frame  10  further comprises two leg members  28 ,  30 . A first leg member  28  extends from and connects the first ends  18  of the main frame members  16  and a second leg member  30  extends from and connects the second ends  30  of the main frame members  16 . In this embodiment each of the leg members  28 ,  30  is substantially U-shaped and includes a base portion  32  and two side portions  34 . Each of the side portions  34  is joined to a respective one of the main frame members  16  at a first end  33  of the side portion  34  and the base portion  32  extends between second ends  35  of the side portions  34 . In this embodiment each of the leg members  28 ,  30  comprises one of the extendable connectors  22 . In particular the base portion  32  of each leg member  28 ,  30  is in the form of an extendable connector  22 . A first section of each leg member  28 ,  30  includes one of the side portions  34  and a first part of the base portion  32 , and a second section of each leg member  28 ,  30  includes the other one of the side portions  34  and a second part of the base portion  32 . The first and second parts of the base portion  32  are in sliding engagement with each other so that an overall length of the base portion  32  can be varied, thereby varying a distance between the main frame members  16 . 
     In this embodiment a first angle between the main frame members  16  and the side portions  34  of the first leg member  28  is different to a second angle between the main frame members  16  and the side portions  34  of the second leg member  30 . The second angle is preferably greater than the first angle. The first angle is preferably between 90° and 120° and the second angle is preferably between 100° and 140°. Preferably a distance between the base portions  32  of the first and second leg members  28 ,  30  is greater than a length of the main frame members  16  between the first and second ends  18 ,  20 . The angle between the leg members  28 ,  30  and the main frame members  16  is preferably fixed. 
     In a preferred embodiment the main frame members  16  and leg members  28 ,  30  are tubular members, so that the convertible frame  10  is strong and lightweight. In these embodiments the first part of the base portion  32  may be partially received within a bore of the second part of the base portion  32  such that the two parts are telescopically connected. By sliding the first and second parts of the base portion  32  with respect to each other, a length of the base portion  32  of the leg member  28 ,  30  can be changed, thereby altering a distance between the main frame members  16 . 
     In particularly preferred embodiments the convertible frame  10  comprises a first tubular section  36  and a second tubular section  38 . Each tubular section  36 ,  38  comprises one of the main frame members  16 , a leg member side portion  34  extending from each end  18 ,  20  of the main frame member  16  and a part of a base portion  32  extending from each side portion  34 . The first and second tubular sections  36 ,  38  are connected to form the complete frame  10  by sliding engagement of the parts of the base portions  32  as described above. 
     The convertible frame  10  may comprise a second pair of extendable connectors  22   b . These extendable connectors  22   b  may extend between the main frame members  16  at a distance from the leg members  28 ,  30 . In some embodiments, such as that shown in  FIG. 9 , a second extendable connector  22   b  may extend between the side portions  34  of each of the leg members  28 ,  30  substantially parallel to but spaced from the base portion  32  of the leg member  28 ,  30 . 
     In other embodiments the extendable connectors may be separate and distinct from the leg members. A separate leg member may extend from each of the first ends and each of the second ends of the main frame members. The extendable connectors may extend between the main frame members at a distance from the leg members. 
     A flexible support  40  is attached to and extends between the main frame members  16 . The flexible support  40  may comprise a layer of fabric or a polymeric or elastomeric sheet, for example. In some embodiments the flexible support  40  may comprise a plurality of flexible strips extending between the main frame members  16 . 
     It will be appreciated that the flexible support  40  is configured to accommodate a change in distance between the main frame members  16 . The flexible support  40  may be elastically stretchable so that when the distance between the main frame members  16  is increased the flexible support  40  stretches and when the distance between the main frame members  16  is decreased the flexible support  40  returns to its original width. Alternatively, the flexible support  40  may not be stretchable. The flexible support  40  may have dimensions such that the flexible support  40  is pulled taut as the distance between the main frame members  16  is increased. 
     With the convertible frame  10  in the first configuration and providing a frame for a rucksack  12 , as shown most clearly in  FIGS. 1 and 3 , the distance between the main frame members  16  defines a width of the rucksack  12 . This distance is preferably between 400 mm and 500 mm, and is most preferably about 450 mm. This makes the rucksack  12  easy to carry and not too bulky. 
     To form the rucksack  12  a bag  42  is connected to the convertible frame  10 . The bag  42  comprises a base  44 , a top  46 , side wall portions or panels  48 , a rear wall portion or panel  50  and a front wall portion or panel  52 . The base  44 , top  46 , side wall portions  48 , rear wall portion  50  and front wall portion  52  together define an interior volume of the bag  42 . 
     In this embodiment the top  46  of the bag  42  comprises a pocket or sleeve  54  for receiving a part of the second leg member  30 . The main frame members  16  extend along and down an exterior of the rear wall portion  50  of the bag  42  and the first leg member  28  extends under the base  44  of the bag  42 . In this way, the interior volume of the bag  42  is substantially disposed within a space defined by the convertible frame  10 , as shown most clearly in  FIG. 2 . 
     A rear flap or rear cover  56  is connected to the rear wall portion  50  of the bag  42 . The rear flap  56  is preferably connected to the rear wall portion  50  along a first edge  57  between the rear wall portion  50  and a first one of the side wall portions  48 . The rear flap  56  is extendable over the main frame members  16  and the flexible support  40  so that the main frame members  16  and flexible support  40  are disposed between the rear flap  56  and the rear wall portion  50  of the bag  42 , as shown most clearly in  FIG. 3 . A free edge  58  of the rear flap  56 , opposite the first edge  57 , is securable to a second one of the side wall portions  48  by means of suitable clips or straps or similar fastening means  59 , to retain the rear flap  56  closed over the main frame members  16 . 
     Because the main frame members  16  and flexible support  40  are disposed between the rear wall portion  50  and rear flap  56  of the bag  42 , the flexible support  40  advantageously provides additional padding at the rear of the rucksack  12  making the rucksack  12  more comfortable to carry. 
     In other embodiments the bag  42  may not include a rear flap  56  that extends over both main frame members  16 . The bag  42  may include a separate cover that extends over each main frame member  16 , or the bag  42  may include straps or clips which attach the rear wall portion  50  of the bag  42  to the main frame members  16 . 
     It may also be desirable for the bag  42  to include straps or clips to connect the base  44  of the bag  42  to the first leg member  28 . In embodiments in which the bag  42  is suspended from the second leg member  30 , however, it is not necessary to directly connect the bag base  44  to the first leg member  28 . 
     In the embodiment of  FIGS. 1 to 3  the bag  42  further comprises a top flap or top cover  60 . The top flap  60  is arranged to cover the remainder of the second leg member  30  not received in the sleeve  54  and to further connect the bag  42  to the convertible frame  10 . As shown in  FIG. 3 , the top flap  60  is connected along a first edge  62  to the sleeve  54  and a second edge  64  of the top flap  60  is securable to the rear flap  56  by means of suitable clips or straps or similar fastening means  66 . This arrangement makes it easier to insert the second leg member  30  into the sleeve  54  to attach the bag  42  to the convertible frame  10 . In other embodiments the bag may not include a top flap and the second leg member may be substantially fully received in the sleeve. 
     It will be appreciated that the rucksack comprises a pair of shoulder straps  68  to enable the bag  42  to be carried in a conventional way as a rucksack. In the embodiment shown in  FIGS. 1 to 3 , the shoulder straps  68  are connected to and extend from regions  69  of the rear flap  56 . In other embodiments the shoulder straps  68  may be connected to other suitable regions of the bag  42 . 
     The rucksack  12  may include other straps for example a waist strap or hip belt and/or a chest or sternum strap that are included in traditional rucksacks. Some or all of the straps of the rucksack  12  may be adjustable in length. The rucksack  12  may also include a further back panel that is arranged to space the rear wall portion  50  and the rear flap  56  from a person&#39;s back when they are wearing the rucksack. This back panel may comprise a mesh and typically provides a space for ventilation between the bag and the person&#39;s back. 
     The advantage of connecting the bag  42  to the convertible frame  10  as described above is that the bag  42  may be attached to and removed from the frame  10  without having to remove the contents of the rucksack from the bag  42 . In this embodiment, the bag  42  further comprises two access flaps  70  in the front wall portion  52  of the bag  42  to permit access to the interior volume of the bag  42 . These flaps  70  allow access to the interior volume both when the bag  42  is connected to the convertible frame  10  and when the bag  42  has been separated from the convertible frame  10 . It will be appreciated that in other embodiments the bag  42  may include fewer than or more than two access flaps. 
     Once the convertible frame  10  has been separated from the bag  42  it may be moved into the second configuration to provide a support  14  for a person. In preferred embodiments, the convertible frame  10 , in the second configuration, forms part of a chair or bed. A preferred embodiment of a bed  72  including the convertible frame  10  is shown in  FIGS. 4 and 5 . The bed  72  may be used as a sun lounger. With the convertible frame  10  in the second configuration the distance between the main frame members  16  defines a width of the bed or chair. This distance is preferably between 600 mm and 700 mm, and is most preferably about 620 mm. 
     In this embodiment the bed  72  further includes a back frame  74  and a foot frame  76 . The back frame  74  shown most clearly in  FIG. 6  comprises two side frame members  78  joined at their first ends  77  by a head frame member  80 . The back frame  74  further comprises two struts  82 , each strut  82  being connected to one of the side frame members  78 . In particular a first end  81  of each strut  82  is connected to a respective side frame member  78  along the length of the side frame member  78  between first and second ends  77 ,  79  of the side frame member  78 . 
     The second end  79  of each of the side frame members  78  is connectable to the second end  20  of a respective main frame member  16 . The second end  83  of each of the struts  82  is connectable to the second leg member  30 . With the back frame  74  connected to the convertible frame  10 , an angle between the side frame members  78  and the main frame members  16  is determined by a length of the struts  82 , the position of the first ends  81  of the struts  82  between the first and second ends  77 ,  79  of the side frame members  78 , and a distance between the second ends  83  of the struts  82  and the second ends  20  of the main frame members  16 . The first end  81  of each strut  82  may be pivotally connected to a respective one of the side frame members  78 . The second end  83  of each strut  82  may be pivotally connected to the second leg member  30 . 
     In some embodiments an angle between the back frame  74  and the convertible frame  10  is adjustable. The angle may be adjusted by altering a length of the struts  82 , moving the position of the first ends  81  of the struts  82  relative to the first and second ends  77 ,  79  of the side frame members  78 , and/or changing the distance between the second ends  83  of the struts  82  and the second ends  20  of the main frame members  16 . 
     In one embodiment, shown in  FIG. 9 , an adjuster  84  is connected to each of the side frame members  78  of the back frame  74 . Each adjuster  84  comprises a plate  86  including a slot  88 . The slot  88  extends parallel to the side frame member  78  and the slot  88  has a series of notches or branches  90  along its length. The first end  81  of each of the struts  82  includes a pin or rod that is engaged with the slot  88 . By seating the pin in a different one of the notches  90 , the position of the first end  81  of the strut  82  along the slot  88 , and therefore along the side frame member  78 , is altered. This changes the angle between the back frame  74  and the main frame members  16 . 
     It will be appreciated that in other embodiments the back frame and/or the convertible frame may comprise other means to allow the back frame to be secured in a plurality of different positions with respect to the convertible frame such that an angle between the side frame members of the back frame and the main frame members of the convertible frame may be varied. 
     The foot frame  76  shown most clearly in  FIG. 8  comprises two side frame members  92  joined at their first ends  91  by a cross member  94 . The foot frame  76  further comprises two legs  96 , each leg  96  being connected to one of the side frame members  92 . In particular a first end  95  of each leg  96  is connected to a respective side frame member  92  proximate the cross member  94 . In a deployed configuration the legs  96  extend substantially perpendicularly from the side frame members  92 . An angle between the legs  96  and the side frame members  92  may be between 90° and 130°. A second end  93  of each of the side frame members  92  is connectable to the first end  18  of a respective main frame member  16 . 
     To allow a person to lie on the bed  72 , in this embodiment the flexible support  40  comprises a central portion  98 , a foot portion  100  and a head portion  102 . The central portion  98  is attached to the main frame members  16  along opposite side edges. The foot portion  100  extends from a first end edge  97  of the central portion  98  and the head portion  102  extends from an opposite second end edge  99  of the central portion  98 . With the convertible frame  10  in the second configuration and the foot frame  76  and back frame  74  connected to the convertible frame  10 , the foot portion  100  of the flexible support  40  may be attached to one or all of the side frame members  92  and cross member  94  so as to extend over the foot frame  76 , and the head portion  102  of the flexible support  40  may be attached to one or all of the side frame members  78  and head frame member  80  so as to extend over the back frame  74 , as indicated in  FIG. 5 . The foot portion  100  of the flexible support  40  may be attached to the foot frame  76  by straps  104  or clips or the like. The head portion  102  of the flexible support  40  may be attached to the back frame  74  by straps  106  or clips or the like. In preferred embodiments the foot portion  100  of the flexible support  40  includes a sleeve within which at least a part of the foot frame  76  is received. The head portion  102  of the flexible support  40  may also include a sleeve within which at least a part of the back frame  74  is received. 
     In preferred embodiments the central portion  98 , foot portion  100  and head portion  102  of the flexible support  40  are integrally formed. As such, in these embodiments, when the frame  10  is converted into the first configuration, the complete flexible support  40 , including the central portion  98 , foot portion  100  and head portion  102 , is disposed between the rear wall portion  50  and the rear flap  56  of the bag  42 . 
     To enable the complete bed  72  to be carried in the rucksack  12 , the foot frame  76  and back frame  74  are preferably convertible into a folded configuration. The struts  82  of the back frame  74  may be pivotally connected to the side frame members  78  so that the struts  82  can be folded into a position in which they extend parallel to the side frame members  78 , as shown by the dashed lines in  FIG. 6 . Similarly, the legs  96  of the foot frame  76  may be pivotally connected to the side frame members  92  so that the legs  96  can be folded into a position in which they extend parallel to the side frame members  92 , as shown by the dashed lines in  FIG. 8 . 
     As described above, the distance between the main frame members  16  in the first configuration is less than the distance between the main frame members  16  in the second configuration. Accordingly, to enable the foot frame  76  and the back frame  74  to be accommodated in the rucksack  12 , it may also be necessary to decrease a distance between the side frame members  92  of the foot frame  76  and the side frame members  78  of the back frame  74 . In the embodiment shown in  FIGS. 6 and 8 , each of the head frame member  80  and the cross member  94  are formed in two parts which are slidably connected to allow a distance between the respective side frame members  78 ,  92  to be altered. The head frame member  80  and the cross member  94  may be telescopic, or may include an extendable connector  22 . 
     In other embodiments each of the head frame member  80  and cross member  94  includes two separable parts. This allows the side frame members  92  of the foot frame  76  to be separated and the side frame members  78  of the back frame  74  to be separated. All four frame components formed due to this separation can then be stowed separately in the rucksack  12 . 
     In other embodiments the foot frame  76  and the back frame  74  may remain attached to the convertible frame  10  when the convertible frame  10  is in the first configuration. The second ends  79  of the side frame members  78  of the back frame  74  may be pivotally connected to the second ends  30  of the main frame members  16 . The second ends  93  of the side frame members  92  of the foot frame  76  may be pivotally connected to the first ends  28  of the main frame members  16 . 
     In other embodiments the distance between the side frame members  92  of the foot frame  76  and the distance between the side frame members  78  of the back frame  74  are both less than the distance between the main frame members  16 . Additionally, both the head frame member  80  and the cross member  94  include an extendable connector  22 . In these embodiments, when the convertible frame  10  is moved into the first configuration, the cross member  94  and the head frame member  80  are also collapsed. The foot frame  76  and the back frame  74  may then be pivoted with respect to the convertible frame  10  so that the main frame members  16  and the side frame members  78 ,  92  lie in the same plane. The complete frame of the bed  72  may then be accommodated within a rear part of the bag  42  of the rucksack  12 , for example between the rear wall portion  50  and the rear flap  56 . 
     In some embodiments the side frame members of the foot frame and/or the back frame may be receivable within a part of the main frame members when the convertible frame is in the first configuration. The main frame members and the side frame members may be telescopic or otherwise slidably connected. 
     It will be appreciated that, in use, the bed  72  is supported on the leg members  28 ,  30  of the convertible frame  10  and on the legs  96  of the foot frame  76 . In embodiments in which the base portions  32  of the leg members  28 ,  30  comprise extendable connectors  22  that include telescopic sections it may be advantageous if a cover or sleeve  108  is disposed over and around at least a part of the telescopic sections, as shown in the embodiment of  FIG. 9 . In particular, the sleeve  108  is preferably configured to prevent ingress of dirt, sand or other particulate material into a join or connection between the telescopic sections which would otherwise prevent or hinder smooth movement of the telescopic sections relative to each other. In other embodiments other means may be provided that prevent ingress of dirt, sand or other particulate material into the join or connection between the telescopic sections. 
     The convertible frame may include a latching or locking mechanism to allow the frame to be latched in the first configuration and/or the second configuration. In preferred embodiments the latching mechanism comprises means for latching the extendable connector in the retracted configuration and means for latching the extendable connector in the extended configuration. In embodiments in which the extendable connector comprises a pair of tubular members slidingly connected to each other the latching mechanism may comprise a biased member or retractable pin attached to one of the tubular members and a hole or a series of holes in the other one of the tubular members. The retractable pin is biased to locate in the hole or one of the holes to retain the tubular members in a fixed position with respect to each other. In some embodiments, the pin may locate in a first one of the holes with the extendable connector in the retracted configuration and in a second one of the holes with the extendable connector in the extended configuration. To allow relative movement of the tubular members between the retracted and extended configurations, the pin can be pressed or retracted to release the pin from the hole such that the tubular members can be slid relative to each other until the pin locates in the other one of the holes. 
     In some embodiments the support for a person may be in the form of a camp bed. In these embodiments the bed may comprise two foot frames, a first foot frame being connected or connectable to the first end of the main frame members and a second foot frame being connected or connectable to the second end of the main frame members. In these embodiments, therefore, the bed does not include a back frame and the bed is in the form of a flat support for a person. 
     In other embodiments the support for a person may be in the form of a chair or stool. The support may include a back frame that is connectable to the first ends of the main frame members and may not include any part that is connectable to the second ends of the main frame members. Alternatively, the support may not include a foot frame or a back frame, but may only comprise the convertible frame. 
     In further embodiments the flexible support may form at least a part of the bag of the rucksack. In particular, the flexible support may form all or part of the base, top, side wall portions, rear wall portion and front wall portion of the bag. In these embodiments the rucksack may comprise one or more inner bags or sacks to hold the contents of the rucksack. When it is desired to convert the convertible frame from the first configuration to the second configuration, the contents of the rucksack are removed from the bag, and the flexible support is opened or unfolded from a configuration in which the flexible support forms the bag to a different configuration in which the flexible support is suspended from the frame to form a chair or bed for supporting a person. 
     It may be desirable if the bag of the rucksack comprises two or more interchangeable pods or sections. Each of the pods or sections may have a different primary function, for example one of the sections may be padded for carrying a camera and one of the sections may be insulated for transporting food and drink. The interchangeable pods or sections may be attached individually to each other to form the complete bag so that, for example, a rear panel of each of the pods forms a part of the rear wall panel of the bag. Alternatively, each of the pods or sections may be insertable into a single outer cover, and the outer cover includes at least the base, top, side wall portions, and rear wall portion of the bag. By providing a set of interchangeable pods, the rucksack may be tailored for a particular purpose or type of outing, for example a nature trek or a picnic. 
     The accompanying  FIGS. 10 to 19  show a convertible frame  210  and rucksack  212  according to a second embodiment of the present invention. The rucksack and frame are substantially similar to the rucksack and frame of the first embodiment described above, and like features have been indicated by reference numerals incremented by 200. The frame  210  is convertible between a first configuration in which the frame  210  forms part of or may be housed within a rucksack  212 , and a second configuration in which the frame  210  forms part of a support  214  for a person, such as a chair or bed. Advantageously, the convertible frame  210  has a first width of about 460 mm, in the first configuration, so that the rucksack  212  is easy and practical to carry, and a second width of about 620 mm, in the second configuration, so that the support  214  has sufficient width to form a comfortable chair or bed. 
     As shown most clearly in  FIGS. 16 and 17 , the convertible frame  210  includes two main frame members  216 . The main frame members  216  are elongate; each extending between first and second ends  218 ,  220 . In this embodiment the main frame members  216  extend parallel to each other in a side by side arrangement with a distance or spacing between them. Preferably the first ends  218  of the main frame members  216  are aligned with each other and the second ends  220  of the main frame members  216  are aligned with each other. The main frame members  216  are connected together by a pair of extendable connectors  222 . The extendable connectors  222  are moveable between a collapsed or retracted configuration and an extended configuration, and movement of the extendable connectors  222  varies a distance between the main frame members  216 . In particular, with the extendable connectors  222  in the retracted configuration there is a first distance between the main frame members  216  and with the extendable connectors  222  in the extended configuration there is a second distance between the main frame members  216 ; the second distance being larger than the first distance. 
     Each extendable connector  222  preferably comprises a pair of tubular members  224 ,  226  slidingly connected to each other; relative sliding of the tubular members  224 ,  226  increasing or decreasing a length of the extendable connector  222 . The extendable connectors  222  may be telescopic. 
     The convertible frame  210  further comprises two leg members  228 ,  230 . A first leg member  228  extends from and connects the first ends  218  of the main frame members  216  and a second leg member  230  extends from and connects the second ends  230  of the main frame members  216 . In this embodiment each of the leg members  228 ,  230  is substantially U-shaped and includes a base portion  232  and two side portions  234 , as described above in relation to the first embodiment. In this embodiment each of the leg members  228 ,  230  comprises one of the extendable connectors  222 . In particular the base portion  232  of each leg member  228 ,  230  is in the form of an extendable connector  222 . A first section of each leg member  228 ,  230  includes one of the side portions  234  and a first part of the base portion  232 , and a second section of each leg member  228 ,  230  includes the other one of the side portions  234  and a second part of the base portion  232 . The first and second parts of the base portion  232  are in sliding engagement with each other so that an overall length of the base portion  232  can be varied, thereby varying a distance between the main frame members  216 . 
     In a preferred embodiment the main frame members  216  and leg members  228 ,  230  are tubular members, so that the convertible frame  210  is strong and lightweight. In these embodiments the first part of the base portion  232  may be partially received within a bore of the second part of the base portion  232  such that the two parts are telescopically connected. By sliding the first and second parts of the base portion  232  with respect to each other, a length of the base portion  232  of the leg member  228 ,  230  can be changed, thereby altering a distance between the main frame members  216 . 
     In this embodiment the convertible frame  210  also includes a second pair of extendable connectors  222   b  as described above. 
     Referring now to  FIGS. 18, 19   a  and  19   b , a flexible support  240  is attached to and extends between the main frame members  216 . The flexible support  240  preferably comprises a layer of fabric or a polymeric or elastomeric sheet. It will be appreciated that the flexible support  240  is configured to accommodate a change in distance between the main frame members  216 . As such, the flexible support  240  may be elastically stretchable so that when the distance between the main frame members  216  is increased the flexible support  240  stretches and when the distance between the main frame members  216  is decreased the flexible support  240  returns to its original width. Alternatively, the flexible support  240  may not be stretchable. The flexible support  240  may have dimensions such that the flexible support  240  is pulled taut as the distance between the main frame members  216  is increased. 
     With the convertible frame  210  in the first configuration and housed within the rucksack  212 , as shown most clearly in  FIG. 14 , the distance between the main frame members  216  defines a width of the rucksack  212 . 
     To form the rucksack  212  a bag  242  is connected to the convertible frame  210 . The bag  242  comprises a base  244 , a top  246 , side wall portions or panels  248 , a rear wall portion or panel  250  and a front wall portion or panel  252 . The base  244 , top  246 , side wall portions  248 , rear wall portion  250  and front wall portion  252  together define an interior volume of the bag  242 . 
     A rear flap or rear cover  256  is connected to the bag  242 . In this embodiment, and as shown in  FIG. 15 , the rear flap  256  includes a lower panel or lower portion  310 , a main panel or portion  312  and an upper panel or portion  314 . The lower portion  310  of the rear flap  256  is connected to the base  244  of the bag  242  along an edge  316  between the base  244  and the front wall portion  252 . In a closed configuration, the rear flap  256  extends over the base  244 , the rear wall portion  250  and the top  246  of the bag  242 . Furthermore, in this closed configuration the rear flap  256  is extendable over the frame  210  and the flexible support  240  so that the frame  210  and flexible support  240  are disposed between the rear flap  256  and the bag  242 , as shown most clearly in  FIG. 13 . 
     In this embodiment, when the frame  210  is housed within the rucksack  212  in the first configuration, the first leg member  228  is disposed between the base  244  of the bag  242  and the lower portion  310  of the rear flap  256 , the second leg member  230  is disposed between the top  246  of the bag  242  and the upper portion  314  of the rear flap  256 , and the main frame members  216  are disposed between the rear wall portion  250  of the bag  242  and the main portion  312  of the rear flap  256 . In this way, the interior volume of the bag  242  is substantially disposed within a space defined by the convertible frame  210 , as shown most clearly in  FIGS. 12 and 13 . 
     The frame  210  may be secured to the bag  242  by straps or clips  317  as shown in  FIGS. 14 and 15 . In particular, in preferred embodiments, straps  317  are provided on the rear wall portion  250  of the bag  242 . The straps  317  may be provided to secure all or part of the frame  210  to the bag  242 . The straps  317  are preferably located on the rear wall portion  250  of the bag  242  (and optionally the base  244  and top  246  of the bag  242 ) such that a user correctly locates the frame  210  on the bag  242 . 
     Side edges  318  of the rear flap  256  are preferably securable to the bag  242  to close the rear flap  256 , such that the frame  210  is disposed between the rear flap  256  and the bag  242 , and the frame  210  is substantially fully covered by the rear flap  256 . In this embodiment the rear flap  256  includes a first part  320  of a zip  324  that extends along each of the side edges  318  of the rear flap  256 . A second part  322  of each of the zips  324  is provided on the bag  242 . In particular, in a preferred embodiment, the first part  320  of each zip  324  extends fully along each of the side edges  318  of the rear flap  256 , such that the first part  320  of the zip  324  extends along the lower portion  310 , main portion  312  and upper portion  314  of the rear flap  256 . In these embodiments the second part  322  of each zip  324  extends along a side edge  326  of the base  244 , a side edge  328  of the rear wall portion  250  and a side edge  330  of the top  246  of the bag  242 . 
     With the rear flap  256  closed, a free end edge  321  of the rear flap  256  lies adjacent a front edge  323  of the top  246  of the bag  242 . 
     In other preferred embodiments the zip also extends along the end edge  321  of the rear flap  256 . In these embodiments, the first part  320  of each zip  324  extends fully along each of the side edges  318  of the rear flap  256  and across at least a part of the end edge  321  of the rear flap  256 , such that the first part  320  of the zip  324  extends along the lower portion  310 , main portion  312  and upper portion  314  of the rear flap  256 . The second part  322  of each zip  324  extends along a side edge  326  of the base  244 , a side edge  328  of the rear wall portion  250 , a side edge  330  of the top  246  of the bag  242  and across the top  246  of the bag  242  proximate and substantially parallel to the front edge  323 . 
     It will be appreciated that in other embodiments the rear flap  256  may be secured closed using any suitable securing means or fasteners. In particular, the rear flap  256  may be secured in its closed position by one or more of suitable clips, straps, toggles, hook and loop fastener, or similar reusable fasteners. 
     As shown most clearly in  FIGS. 10 to 12 , in this embodiment the rucksack  212  further comprises a top flap or top cover  260 . The top flap  260  is arranged to cover the end edge  321  of the rear flap  256 . The top flap  260  is connected along a first edge  262  to an upper region of the front wall portion  252  of the bag  242 . A second edge  264  of the top flap  260  is securable to the rear flap  256  by means of a suitable fastener  266 . A first part of the fastener  266  is preferably provided on the top flap  260  and a second part of the fastener  266  is preferably provided on the rear flap  256 . In this embodiment the fastener  266  is a buckle clip, and more particularly a side release buckle clip. In other embodiments the fastener  266  may, for example, be any suitable clip, buckle, strap, zip, toggle, or hook and loop fastener. The top flap  260  preferably includes side panels  324  that extend over at least a part of the side edge  318  of the upper portion  314  of the rear flap  256 , when both the rear flap  256  and top flap  260  are closed. The provision of a top flap  260  that covers at least the end edge  321  of the rear flap  256  helps to prevent water (e.g. rain) and particulate matter (e.g. dirt, sand, stones) entering the space between the rear flap  256  and the bag  242 . Furthermore, the top flap  260  provides tension between the front wall portion  252  of the bag  242  and the rear flap  256 , such that the bag  242  is held securely to the frame  210 . 
     It will be appreciated that the rucksack comprises a pair of shoulder straps  268  to enable the bag  242  to be carried in a conventional way as a rucksack. As shown most clearly in  FIGS. 11 and 13 , in this embodiment the shoulder straps  268  are connected to and extend from the rear flap  256 . 
     The rucksack  212  may include other straps for example a waist strap or hip belt and/or a chest or sternum strap that are included in traditional rucksacks. Some or all of the straps of the rucksack  212  may be adjustable in length. The rucksack  212  may also include a further back panel that is arranged to space the rear flap  256  from a person&#39;s back when they are wearing the rucksack. This back panel may comprise a mesh and typically provides a space for ventilation between the bag and the person&#39;s back. 
     Once the convertible frame  210  has been separated from the bag  242  it may be moved into the second configuration to provide a support  214  for a person. In preferred embodiments, the convertible frame  210 , in the second configuration, forms part of a chair or bed. A preferred embodiment of a bed  272  including the convertible frame  210  is shown in  FIG. 18 . The bed  272  may be used as a sun lounger. With the convertible frame  210  in the second configuration the distance between the main frame members  216  defines a width of the bed or chair. This distance is preferably between 600 mm and 700 mm, and is most preferably about 620 mm. 
     In this embodiment the bed  272  further includes a back frame  274  and a foot frame  276 . The back frame  274  comprises two side frame members  278  joined at their first ends  277  by a head frame member  280 . The back frame  274  further comprises two struts  282 , each strut  282  being connected to one of the side frame members  278 . In particular a first end  281  of each strut  282  is connected to a respective side frame member  278  along the length of the side frame member  278  between first and second ends  277 ,  279  of the side frame member  278 . 
     The second end  279  of each of the side frame members  278  is connectable to the second end  220  of a respective main frame member  216 . A second end  283  of each of the struts  282  is connectable to the second leg member  230 . With the back frame  274  connected to the convertible frame  210 , an angle between the side frame members  278  and the main frame members  216  is determined by a length of the struts  282 , the position of the first ends  281  of the struts  282  between the first and second ends  277 ,  279  of the side frame members  278 , and a distance between the second ends  283  of the struts  282  and the second ends  220  of the main frame members  216 . 
     In this embodiment an angle between the back frame  274  and the convertible frame  210  is adjustable. An adjuster  284  is provided on each of the side frame members  278  of the back frame  274 . Each adjuster  284  comprises a plate including a slot. The slot extends parallel to the side frame member  278  and the slot has a series of notches or branches along its length. The first end  281  of each of the struts  282  includes a pin or rod that is engaged with the slot. By seating the pin in a different one of the notches, the position of the first end  281  of the strut  282  along the slot, and therefore along the side frame member  278 , is altered. This changes the angle between the back frame  274  and the main frame members  216 . 
     The foot frame  276  comprises two side frame members  292  joined at their first ends  291  by a cross member  294 . The foot frame  276  further comprises two legs  296 , each leg  296  being connected to one of the side frame members  292 . In particular a first end  295  of each leg  296  is connected to a respective side frame member  292  proximate the cross member  294 . In a deployed configuration the legs  296  extend substantially perpendicularly from the side frame members  292 . An angle between the legs  296  and the side frame members  292  may be between 90° and 130°. A second end  293  of each of the side frame members  292  is connectable to the first end  218  of a respective main frame member  216 . 
     To allow a person to lie on the bed  272 , in this embodiment the flexible support  240  comprises a central portion  298 , a foot portion  300  and a head portion  302 . The central portion  298  is attached to the main frame members  216  along opposite side edges. The foot portion  300  extends from a first end edge  297  of the central portion  298  and the head portion  302  extends from an opposite second end edge  299  of the central portion  298 . With the convertible frame  210  in the second configuration and the foot frame  276  and back frame  274  connected to the convertible frame  210 , the foot portion  300  of the flexible support  240  may be attached to one or all of the side frame members  292  and cross member  294  so as to extend over the foot frame  276 , and the head portion  302  of the flexible support  240  may be attached to one or all of the side frame members  278  and head frame member  280  so as to extend over the back frame  274 . 
     In this embodiment the foot portion  300  of the flexible support  240  comprises an elastic strap or section  332  adjacent or at a free end edge  334  of the foot portion  300  of the flexible support  240 . The elastic section  332  may be in the form of a sleeve within which at least a part of the foot frame  276  is received. To partially attach the foot portion  300  of the flexible support  240  to the foot frame  276  the elastic strap or section  332  is stretched over the cross member  294  of the foot frame  276 . Similarly, in this embodiment the head portion  302  of the flexible support  240  comprises an elastic strap or section  336  adjacent or at a free end edge  338  of the head portion  302  of the flexible support  240 . The elastic section  336  may be in the form of a sleeve within which at least a part of the back frame  274  is received. To partially attach the head portion  302  of the flexible support  240  to the back frame  274  the elastic strap or section  338  is stretched over the head frame member  280  of the back frame  274 . 
     In preferred embodiments the foot portion  300  of the flexible support  240  further comprises one or more securement members or clips  340  to secure each side edge  342  of the foot portion  300  to a respective one of the two side frame members  292  of the foot frame  276 . Similarly, the head portion  302  of the flexible support  240  further comprises one or more securement members or clips  340  to secure each side edge  344  of the head portion  302  to a respective one of the two side frame members  278  of the back frame  274 . 
     The clips may be of any suitable design or configuration that allows the foot portion  300  and head portion  302  of the flexible support  240  to be easily and repeatedly attached to and removed from the foot frame  276  and back frame  274  respectively. In a preferred embodiment, and as shown in  FIGS. 18, 19   a  and  19   b , each of the clips  340  may comprise an elongate channel  346  configured to engage with a respective one of the side frame members  292 ,  278 . In this embodiment the clip  340  comprises an elongate hollow tubular element  348  extending between first and second ends  350 ,  352 . A longitudinal slit or gap  354  is provided in the tubular element  348 , the slit  354  extending fully along the length of the tubular element  348  between the first and second ends  350 ,  352 . 
     A diameter of a bore  356  of the tubular element  348  is preferably slightly larger than or substantially the same as an outer diameter of the side frame member  292 ,  278 . In some embodiments, however, the diameter of the bore  356  may be slightly smaller than the outer diameter of the side frame member  292 ,  278 . A width of the slit  354 , defined between side edges  358 , is substantially smaller than the outer diameter of the side frame member  292 ,  278 . The tubular element  348  is resilient such that, in use, when the tubular element  348  is pressed against the side frame member  292 ,  278 , with the side edge  358  in contact with the side frame member  292 ,  278 , the side edges  358  are pushed apart so that the tubular element  348  can be pressed over the side frame member  292 ,  278  until the side frame member  292 ,  278  is received in the bore  356  of the tubular element  348  (as indicated by the dashed lines in  FIG. 19 a   ). 
     In preferred embodiments the tubular element  348  includes a pair of flanges  347 ,  349 . Each flange  347 ,  349  extends longitudinally along the tubular element  348 . Each flange  347 ,  349  extends radially outwards from an outer surface of the tubular element  348 . The flanges  347 ,  349  preferably extend from diametrically opposite sections of the tubular element  348 . One of the side edges  342 ,  344  of the foot portion  300  or head portion  302  is attached to a first one of the flanges  347  and a second one of the flanges  349  provides a handle or grip element to aid a user when removing the clip  340  from the side frame member  292 ,  278 . 
     In other embodiments, in place of or in addition to the clips  340 , the foot portion  300  and the head portion  302  of the flexible support  240  may comprise one or more straps  359  or other similar fasteners to secure each of the side edges  342  of the foot portion  300  to a respective one of the two side frame members  292  of the foot frame  276  and each of the side edges  344  of the head portion  302  to a respective one of the two side frame members  278  of the back frame  274 . 
     In preferred embodiments the central portion  298 , foot portion  300  and head portion  302  of the flexible support  240  are integrally formed. As such, in these embodiments, when the frame  210  is converted into the first configuration, the complete flexible support  240 , including the central portion  298 , foot portion  300  and head portion  302 , is disposed between the rear wall portion  250  and the rear flap  256  of the rucksack  212 . 
     To enable the complete bed  272  to be carried in the rucksack  212 , the foot frame  276  and back frame  274  are preferably convertible into a folded configuration. The struts  282  of the back frame  274  may be pivotally connected to the side frame members  278  so that the struts  282  can be folded into a position in which they extend at least substantially parallel to the side frame members  278 . Similarly, the legs  296  of the foot frame  276  are preferably pivotally connected to the side frame members  292  so that the legs  296  can be folded into a position in which they extend parallel to the side frame members  292 . 
     As described above, the distance between the main frame members  216  in the first configuration is less than the distance between the main frame members  216  in the second configuration. Accordingly, to enable the foot frame  276  and the back frame  274  to be accommodated in the rucksack  212 , it may also be necessary to decrease a distance between the side frame members  292  of the foot frame  276  and the side frame members  278  of the back frame  274 . In some embodiments each of the head frame member and the cross member may be formed in two parts which are slidably connected to allow a distance between the respective side frame members  278 ,  292  to be altered. The head frame member and the cross member may be telescopic, or may include an extendable connector. 
     In preferred embodiments the foot frame  276  comprises two separable frame elements  277 , each of the separable frame elements  277  comprising one of the side frame members  292  and a part of the cross member  294 . Similarly, the back frame  274  preferably comprises two separable frame elements  275 , each of the separable frame elements  275  comprising one of the side frame members  278  and a part of the head frame member  280 . In this way, each of the separable frame elements  275 ,  277  is substantially L-shaped. All four separable frame elements  275 ,  277  can be stowed separately in the rucksack  212 , for example as shown in  FIGS. 14, 16 and 17 . 
     The convertible frame  210  preferably includes a latching mechanism to allow the frame  210  to be latched in the first configuration and/or the second configuration. In some embodiments the extendable connectors  222  comprise tubular members and the latching mechanism comprises a biased member or retractable pin  360  attached to one of the tubular members and a hole  362  or a series of holes in the other one of the tubular members. The retractable pin  360  is biased to locate in the hole  362  or one of the holes to retain the tubular members in a fixed position with respect to each other. In some embodiments, the pin may locate in a first one of the holes with the extendable connector in the retracted configuration and in a second one of the holes with the extendable connector in the extended configuration. To allow relative movement of the tubular members between the retracted and extended configurations, the pin  360  can be pressed or retracted to release the pin  360  from the hole  362  such that the tubular members can be slid relative to each other until the pin  360  locates in the other one of the holes  362 . In preferred embodiments the latching mechanism is provided in or on the second pair of extendable connectors  222   b.    
     Similarly, each of the back frame  274  and foot frame  276  may include a latching mechanism. In particular, in embodiments in which each of the back frame  274  and foot frame  276  includes two separable frame elements  275 ,  277 , the latching mechanism is configured to latch the separable frame elements  275 ,  277  together such that the side frame members  292  of the foot frame  276  are in the correct orientation with respect to each other, the side frame members  278  of the back frame  274  are in the correct orientation with respect to each other, and there is the correct distance between each of the foot frame side frame members  292  and each of the back frame side frame members  278 , to allow the foot frame  276  and back frame  274  to be connected to the convertible frame  210  in the second configuration. 
     In preferred embodiments the cross member  294  and the head frame member  280  are telescopic and comprise hollow tubular members. In these embodiments the latching mechanism of the foot frame  276  may comprise a retractable pin  360  attached to a first part of the cross member  294  and a hole  362  in a second part of the cross member  294 . Similarly, the latching mechanism of the back frame  274  may comprise a retractable pin  360  attached to a first part of the head frame member  280  and a hole  362  in a second part of the head frame member  280 . The retractable pin  360  is biased to locate in the hole  362  when the separable frame elements are joined together. To allow the separable frame elements to be separated, the pin  360  can be pressed or retracted to release the pin  360  from the hole  362  such that the tubular members can be slid relative to each other to withdraw one of the tubular members from the other of the tubular members. 
     In other preferred embodiments the latching mechanisms of the foot frame  276  and back frame  274  comprise a bayonet-style latching mechanism in which a pin is engageable with a slot. Preferably the slot is L-shaped having a first section extending substantially parallel to the longitudinal axis of the cross member  294  or head frame member  280  and a second section extending transverse to the longitudinal axis of the cross member  294  or head frame member  280 . 
     The separated and individual separable frame elements  275 ,  277  can be stowed in the rucksack  212  within a region defined by the frame  210 , as shown most clearly in  FIG. 14 . Preferably one end of each of the separable frame elements  275 ,  277  is retained in a pocket or sleeve attached to the rear wall portion  250  of the bag  242 . A strap or loop may be provided to secure a region of the separable frame elements  275 ,  277  proximate a second end of the separable frame elements  275 ,  277  to the rear wall portion  250  of the bag  242 . 
     The advantage of connecting the bag  242  to the convertible frame  210  as described above is that the bag  242  may be attached to and removed from the frame  210  without having to remove the contents from the bag  242 . In one particular embodiment of a rucksack  412 , shown in  FIGS. 20 to 25 , the bag  442  further comprises two access flaps  470  in the front wall portion  452  of the bag  442  to permit access to the interior volume of the bag  442 . These flaps  470  allow access to the interior volume both when the bag  442  is connected to the convertible frame  210  and when the bag  442  has been separated from the convertible frame  210 . In preferred embodiments the interior volume of the bag  442  is divided into two sections. An upper section  564  of the interior volume is accessed through an upper one of the access flaps  470  and a lower section  566  of the interior volume is accessed through a lower one of the access flaps  470 . In other embodiments the interior volume may not be divided into two sections; however, two access flaps may still be provided. Alternatively the bag may only include a single access flap in the front wall portion of the bag. 
     In this embodiment the rucksack  412  further comprises two side pockets  568  connected to each of the side wall portions  448  of the bag  442 . The side pockets  568  may be of any suitable design. Each of the side pockets  568  has an internal volume and in preferred embodiments, when the internal volume is filled with contents, the internal volume of the side pocket  568  extends into the interior volume of the bag  442 . 
     As shown in  FIG. 23 , the bag  442  further comprises an interchangeable pod or inner bag  570 . The pod  570  may have a specific primary function, for example the pod  570  may be padded for carrying a camera or may be insulated for transporting food and drink. In this embodiment the pod is sized to be receivable within the lower section  566  of the interior volume of the bag  442 . 
     To make the rucksack  412  comfortable to carry, the rucksack  412  preferably includes padded shoulder straps  468  and a padded waist strap. As shown in  FIG. 25 , the rucksack  412  preferably also includes a sternum strap extending between the two shoulder straps  468 . It will be appreciated that all of the straps are preferably adjustable as is known in the art. 
     The present invention therefore provides a support for a person, such as a chair or bed, that is more easily transported to a place of use. In particular the support provides a frame for, and therefore may be carried as part of, a rucksack.