Abstract:
The disclosure generally describes a sofa convertible into a bed. In one embodiment, the sofa includes a support and guide structure, a mattress that is movable relative to the support and guide structure. The sofa can be moved between a bed configuration and a sofa configuration. In the bed configuration, the mattress has a bearing surface which extends horizontally. In the sofa configuration an upper portion of the mattress is folded upwards relative to a lower portion of the mattress. In addition, the bearing surface of the upper portion of the mattress forms the bearing surface of a backrest against for supporting the back of a person in a seated position.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The present invention generally relates to a sofa convertible into a bed.  
         [0003]     2. Description of the Related Art  
         [0004]     The document EP-A-811341 by the same Applicant discloses a sofa convertible into a bed in which the mattress in the sofa configuration is folded underneath the sliding support structure. In this known solution, the stationary support structure of the sofa-bed comprises a backrest structure borne by two support arms which are connected to the rear support legs of the sofa. The backrest structure is capable of assuming a vertical configuration in which it forms the head of the bed or a rearwards folded configuration forming the backrest of the sofa.  
         [0005]     The documents U.S. Pat. No. 2,568,366 and U.S. Pat. No. 4,586,206 describe sofas convertible into beds with the characteristics contained in the preamble of the main claim. In both these known solutions, the mattress is movable relative to a support and structure guide between a bed configuration in which the mattress extends horizontally and a sofa configuration in which an upper portion of the mattress is folded upwards relative to a lower portion. The support structure of the sofa comprises a stationary backrest structure with a rear wall and a front wall, mutually distanced and defining a compartment which, in the sofa configuration, receives the upper portion of the mattress.  
       BRIEF SUMMARY OF THE INVENTION  
       [0006]     One object of the present invention is to provide a sofa convertible into a bed having a simpler, more compact and more economical structure.  
         [0007]     According to one aspect, a sofa that is convertible into a bed includes a support, guide structure and mattress. The mattress can be movable relative to the support and guide structure between a bed configuration and a sofa configuration. The bed configuration provides a bearing surface of the mattress that extends horizontally. The sofa configuration provides an upper portion of the mattress that is folded upwards relative to a lower portion of the mattress. The upper portion of the mattress forms a bearing surface for a backrest. 
     
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS  
       [0008]     A preferred embodiment of the present invention shall now be described with reference to the accompanying drawings, provided purely by way of non limiting example, in which:  
         [0009]      FIG. 1  is a partially sectioned view of a sofa-bed according to the present invention in bed configuration,  
         [0010]      FIG. 2  is a side view of the sofa-bed of  FIG. 1 ,  
         [0011]      FIG. 3  is a side view showing the sofa-bed according to the invention in sofa configuration,  
         [0012]      FIG. 4  is a partial section in enlarged scale according to the arrow IV-IV of  FIG. 3 ,  
         [0013]      FIG. 5  is a partial plan bottom view of a mattress of a sofa-bed according to the invention,  
         [0014]      FIG. 6  is a partial perspective view of the part designated by the arrow VI-VI in  FIG. 5 ,  
         [0015]      FIG. 7  is a partial plan view showing the support and guide structure of the sofa-bed according to the invention in the extended position,  
         [0016]      FIGS. 8 and 9  are view in enlarged scale of the parts designated by the arrows VIII and IX in  FIG. 7 ,  
         [0017]      FIG. 10  is a partial plan view showing the support and guide structure of a sofa-bed in the retracted position,  
         [0018]      FIG. 11  is a section according to line XI-XI of  FIG. 10 ,  
         [0019]      FIG. 12  is a partial front view of the sofa-bed according to the invention, and  
         [0020]      FIG. 13  is a partially sectioned front view showing in enlarged scale the detail designated by the arrow XIII in  FIG. 12 . 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0021]     With reference to  FIGS. 1 and 2 , the reference number  10  indicates a sofa convertible into a bed according to the present invention. The sofa-bed  10  comprises a support and guide structure  12 , movable between an extracted position and a retracted position in the manner that will be described below. The support and guide structure  12  bears a mattress  14  having a bearing surface  16  which in the bed configuration illustrated in  FIGS. 1 and 2  extends horizontally and whereon is destined to bear the occupant or the occupants of the bed in reclined position. In the bed configuration, the mattress  14  has a rectangular shape with two greater sides  18  and two smaller sides  20 . The mattress  14  is movable between a sofa configuration and a bed configuration and vice versa in the direction designated by the double arrow  22  in  FIGS. 1 and 2 . According to a preferred characteristic of the present invention, the greater sides  18  of the mattress  14  extend parallel to the direction of motion  22  of the mattress  14 .  
         [0022]     With reference to  FIGS. 1, 2  and  3 , the mattress  14  has an upper portion  14   a  and a lower portion  14   b . In the bed configuration, the two portions  14   a ,  14   b  are substantially aligned and coplanar to each other. In the sofa configuration shown in  FIG. 3 , the upper portion  14   a  extends upwards relative to the lower portion  14   b , according to a general “L” configuration. In the sofa configuration shown in  FIG. 3 , the bearing surface  16   a  of the upper mattress portion  14   a  constitutes the bearing surface of the backrest of the sofa, against which directly bears the back of an occupant of the sofa in the sitting position. The bearing surface  16   b  of the lower mattress portion  14   b  in the sofa configuration constitutes the seating surface.  
         [0023]     With reference to  FIGS. 1, 5  and  6 , the upper portion  14   a  of the mattress  14  bears a plurality of support rods  24  which extend parallel to the smaller sides  20  of the mattress  14 . The support rods  24  are applied to the lower surface  26  of the mattress  14 , opposite to the bearing surface  16 . Preferably, on the lower surface  26  of the mattress  14  is sewn a layer of fabric  28  forming a plurality of transverse tubular seats  30  ( FIG. 6 ) within each of which is inserted a respective support rod  24 . Each rod  24  is provided at each of its ends with an idle guide roller  32 , free to rotate about a transverse axis.  
         [0024]     Preferably, the support rods  24  extend only along the upper part  14   a  of the mattress  14 , which occupies about ⅔ of the total length of the mattress  14 . The lower portion  14   b  of the mattress  14  is preferably provided on its lower surface with a panel of yielding material  34 , preferably made of elastomeric material. The panel  34  can be applied on the lower surface of the lower portion  14   b  by stitching or by means of Velcro® tape. Preferably, the panel of yielding material  34  has a thickness that is substantially equal to the thickness of the support rods  24 .  
         [0025]     With reference to  FIGS. 1 through 3 , the support and guide structure  12  of the sofa-bed  10  comprises a stationary base  36  provided with one or more ground support elements  38 . Two guide uprights  40  are fastened to the support base  36  and extend upwards starting therefrom. The two guide uprights  40  extend on the two opposite sides of the sofa-bed  10 . Each of the guide uprights  40  has a guide channel  42  engaged in sliding fashion by the rollers  32  borne by the support rods  24 . The guide uprights  40  have an upper portion  40   a  with substantially rectilinear shape and a lower portion  40   a  with an arched shape, with the concavity oriented towards the front part of the sofa-bed  10 .  
         [0026]     The support and guide structure  12  comprises two stationary, mutually parallel horizontal guides  48 , fastened to the support base  36  in the vicinity of the lower ends of the guide uprights  40 . The two stationary horizontal guides  48  bear two movable horizontal guides  50 , able to move telescopically relative to the stationary guides  48  in the direction indicated by the double arrow  22  in  FIG. 1 . In turn, the two movable horizontal guides  50  bear a movable frame  52  able to slide telescopically relative to the guides  50  in the direction indicated by the double arrow  22 . The movable frame  52  is provided with two pairs of idle wheels  54  which bear down on the floor.  
         [0027]      FIGS. 8, 9  and  13  show the node in which, according to a preferred embodiment of the present invention, is achieved the sliding connection between the movable guides  50  and the stationary guides  48  ( FIG. 8 ) and the sliding connection between the movable frame  52  and the movable guides  50  ( FIG. 9 ). Guides  48  and  50  are preferably constituted by aluminium section bars with substantially C shaped cross section. Each stationary guide  48  has an upper rolling track and a lower rolling track. Each of these tracks is engaged by two or more pairs of idle wheels  56  borne by the corresponding movable guide  50 . in similar fashion, each movable guide  50  has an upper rolling track and a lower rolling track, each engaged by two or more pairs of idle wheels  58  borne by the movable frame  52 .  
         [0028]     The movable frame  52  is preferably provided with a support element  60  which can be formed by a panel or by a structure formed by a series of flexible belts.  
         [0029]     The operation of the sofa-bed according to the present invention is as follows. Starting from the sofa configuration shown in  FIG. 3 , the user simply needs to pull the movable frame  52  in the direction indicated by the arrow  62  in  FIG. 3  in order to shift to the bed configuration. The movable guides  50  and the movable frame  52  extend until reaching the position shown in  FIGS. 2 and 7 . The lower portion  14   b  of the mattress  14  is connected to the movable frame  52 . Consequently, the movement from the retracted position to the extracted position of the movable frame  52  causes the movement of the mattress  52  from the sofa configuration shown in  FIG. 3  to the bed configuration shown in  FIG. 2 . The guides  48  and  50  are provided with respective end stops which define the position of greatest extraction of the movable guides  50  and of the movable frame  52 .  
         [0030]     To return to the sofa configuration starting from the bed configuration, it is sufficient to push the movable frame  52  towards the guide uprights  40 . During this motion, the upper part  14   a  of the mattress  14  moves upwards. The upward motion of the upper portion  14   a  of the mattress  14  is guided by the rollers  32  borne at the ends of the support rods  24  which engage in sliding fashion the guides  42  of the guide uprights  40 .  
         [0031]     The sofa-bed  10  can also be provided with a tubular pillow  64  separated from the mattress  14 , which, in the sofa configuration, can be positioned in the junction area between the backrest portion  14   a  and the seat portion  14   b  of the mattress  14 .  
         [0032]     All of the above U.S. patents, U.S. patent application publications, U.S. patent applications, foreign patents, foreign patent applications and non-patent publications referred to in this specification and/or listed in the Application Data Sheet, are incorporated herein by reference, in their entirety.  
         [0033]     From the foregoing it will be appreciated that, although specific embodiments of the invention have been described herein for purposes of illustration, various modifications may be made without deviating from the spirit and scope of the invention. Accordingly, the invention is not limited except as by the appended claims.