referring now to fig1 and 2 of the drawings , a toaster in accordance with one embodiment of the invention comprises a main housing 1 in which is defined a slot - like toasting chamber 2 , flanked by respective heating elements , such as that shown at 3 , of any convenient kind . the heating elements are typically substantially rectangular , planar elements as shown , supported in known manner so as to stand vertically to either side of chamber 2 , effectively forming side - walls thereof . each heating element is , in this example , protected by a grid - like guard member 4 from direct contact with the foodstuffs inserted into the chamber 2 . a food - supporting carriage 5 is provided in the chamber 2 , and the carriage is supported , in known manner , by means of a conventional support structure ( not shown ) configured to permit the carriage to be latched in a lower position at which foodstuffs are exposed to said heating elements for toasting , for releasing said carriage upon completion of a toasting cycle , and for raising the carriage to an upper , presentation position in which toasted foodstuffs can be removed from the toaster . user - operable means , including a slider mechanism 6 is provided for varying the width dimension a of the chamber to accommodate foodstuffs of differing thickness . in this example , the mechanism 6 is disposed internally of an outer casing ( not shown ) of metal or plastics material and is operated by means of a lever arrangement ( not shown ) accessible to the user externally of the casing . the internal mechanism 6 includes , in this example , a slot arrangement 7 ( best seen in fig1 ( b )) comprising several constrictions which define respective discrete width settings for the slot - like chamber 2 . in alternative embodiments , the width setting may be smoothly variable to any chosen position between two extreme end stops . as shown in more detail in fig2 , the carriage 5 comprises first and second elongate members 51 and 52 extending along the length dimension b of said chamber and disposed respectively to one and the other side of the chamber 2 . a plurality of linking members 53 a to 53 n are provided , each linking the elongate members 51 and 52 and pivotally mounted to each elongate member ; and resilient means 54 are provided to urge the elongate members 51 and 51 apart whereby the carriage 5 adapts automatically to variations in the width dimension a of the chamber . in this respect , it will be appreciated that in this embodiment the member 52 remains in contact with the heater guard in its side of the slot 2 whilst the member 51 is mobile laterally of the toaster slot ; moving towards or away from the member 52 as appropriate to maintain contact with the heater guard at the other side of the slot . the member 51 is either pushed towards the member 52 by contact with the heater guard 4 when the slot 2 is narrowed by a user , or urged away from the member 52 by the resilient means 54 when the slot 2 is widened . in this example of the invention , the resilient means 54 comprises a single coil spring , fixedly supported upon the elongate member 52 and configured to operate in compression , though it could alternatively , be mounted and configured so as to operate in tension , depending upon the detailed construction of the assembly . also in this example , the spring is connected to the linking member 53 a but it could alternatively , or in addition , be connected to one or more of the other linking members . by this means , in any event , the necessary resilient urge is applied in a simple and cost - effective manner . in further alternative configurations , the resilient urge may be provided by a torsion spring , and / or by plural spring members of any convenient kind carried by one , the other , or both of the elongate members 51 and 52 ; each such spring member being coupled between a respective fixed location on its elongate means and a respective one or more of the linking members . if plural spring members are provided , it is preferable to distribute them evenly among said linking members . it is particularly preferred ( though not essential ) that pivotal mounting points for the linking members 53 a to 53 n are regularly distributed along the elongate members 51 and 52 , thereby providing an even distribution of the resilient urging force . in some preferred embodiments of the invention , the mobile member 51 ( or at least a part thereof ) is usefully made of , or coated with , a robust and slippery material , such as a ceramic or a non - stick material such as that sold under the registered trademark teflon ®, which will resist repeated wiping contact with the heater guard 4 . referring now to fig3 , 4 and 5 , which show various operational thickness settings for a toaster in accordance with a second embodiment of the invention , the carriage 60 comprises first and second elongate members 61 and 62 extending , as before , along the length dimension b of the toasting chamber 70 and disposed respectively to one and the other side of the chamber 70 . a plurality of paired , chevron - like linking members such as 63 a and 63 b are provided ; each linking member being pivotally linked to a respective elongate member 61 or 62 and each pair of linking members , such as 63 a and 63 b being pivotally linked to each other , as at 64 , 65 , and 66 . each end of each of the elongate members 61 , 62 is secured by means of an eye such as 67 to an upright wire such as 68 forming part of the heater guard at the relevant side of the chamber 70 , such that the carriage 60 can execute its required vertical movements simply by each eye such as 67 running up or down on its respective wire such as 68 . when the toaster chamber is widened or narrowed , however , the elongate members follow the relevant movement towards or away from another as a result of their direct attachment to the wires such as 68 . in this embodiment of the invention , therefore , there is no need for any resilient means to urge the elongate members apart , as there was in the first embodiment , since the carriage 60 adapts , as a result of its construction , to variations in the width dimension a of the chamber 70 simply by the elongate members 61 and 62 being towards each other or pulled away from each other as appropriate by their direct mechanical connection to the wires such as 68 . it will also be appreciated that , because of the folding capability of the pairs of linking members such as 63 a and 63 b afforded by their central pivots such as 66 , the overall longitudinal offset between the two elongate members 61 and 62 that needs to be accommodated in the second embodiment of the invention is only around half of that needed for the elongate members 51 and 52 in the first embodiment . the inner surface of each of the elongate members 61 and 62 ( i . e . that surface facing away from the heaters and thus into the interior of the chamber 70 ) is formed with a plurality of notches , such as 69 , to accommodate the central pivots , such as 66 , of the respective pairs of linking members , such as 63 a and 63 b , when the toasting chamber 70 is set to a narrow setting as illustrated in fig5 . in some preferred embodiments of the invention , the eyes such as 67 are usefully made of , or coated with , a robust and slippery material , such as a ceramic or a non - stick material such as that sold under the registered trademark teflon ®, which will resist repeated wiping contact with the wires such as 68 during upward and downward movements executed by the carriage 60 at various stages during the toasting process . alternatively , or in addition , the wires such as 68 may be so formed or coated . alternatively , any convenient form of linear bearing capable of operating in the toasting chamber environment can be used to link the elongate members 61 and 62 to the wires such as 68 .
a variable - width toaster is described , in which the food - supporting carriage adapts readily , robustly and in a cost - effective manner to different width settings of the toasting chamber . respective elongate members are mounted to either side of the toasting chamber and are linked together by linking members which form part of the food - supporting surface and are pivotally attached to the elongate members to accommodate lateral relative movement between the elongate members as the width of the toasting chamber is varied . in one embodiment , unitary linking members link the two elongate members and the elongate members are urged apart by a spring . in another embodiment , chevron - like linking members , comprising pairs of pivotally associated linking members are employed .