Patent Publication Number: US-9420894-B2

Title: Convertible seat/bed having noncoplanar bed base sections

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application claims priority to U.S. provisional application 61/828,450, filed May 29, 2013, entitled Extendable and Flip-Over Convertible Seat, incorporated herein by reference in its entirety. This application is also related to U.S. patent application Ser. No. 14/290,078 filed concurrently and commonly owned, and entitled “Extendable and Flip-Over Convertible Seat,” which is also hereby incorporated by reference in its entirety. 
    
    
     BACKGROUND 
     1. Technical Field 
     The present invention pertains to the field of convertible seats, and more specifically, to convertible seats that provide a comfortable lying surface for a user. 
     2. Background of the Invention 
     Seating units (e.g., sofas, chairs, etc.) that are convertible into beds are popular with consumers because of their multi-functionality. Many consumers find it very convenient to have a seating unit that can provide a bed for a guest; as such a unit can eliminate the need for an additional, separate bed. Some such seating unit designs include their own complete mattress that is folded within a cavity of the sofa or chair during periods of non-use. This type of sofa-bed can be quite heavy, and typically requires not only a separate mattress, but also a relatively intricate mechanism to control the unfolding and folding of the mattress. 
     Other sofa-beds lack a complete mattress, but instead are constructed of separate sections that serve as support surfaces of the sofa or chair and unfold to form a flat, mattress-like lying/sleeping surface. Such a sofa-bed includes a backrest, a seat and a “subseat” that unfold to form a horizontal lying surface. In the folded “chair” configuration, the backrest is generally upright, and the seat and “subseat” fold upon each other (with the subseat in an inverted position). The backrest is guided between positions by preformed slots in the arms of the sofa that receive posts that extend laterally from the backrest. The backrest is coupled to the seat and subseat via an angled link. The subseat is pivotally attached at one end to the arms and is hinged at the other end to the seat. 
     Convertible beds are popular in health care environments (e.g., hospitals), because they provide a family member visiting a patient with a furniture piece in the patient&#39;s room on which one can sit, lie down on, or sleep. Because hospital rooms are typically short on available space, convertible beds used in hospital rooms are typically the width of a chair. Such beds may also be used in recreational vehicles. Generally speaking, such beds are designed with compactness and ease of conversion as their primary features, with little to no regard for the comfort of the user. An example of such configuration is illustrated in  FIGS. 1A and 1B .  FIG. 1A  is a perspective view of a convertible chair  10  shown in the folded or chair configuration.  FIG. 1B  is a side section view of the convertible chair  10  shown in the unfolded (i.e., bed) configuration. 
     BRIEF SUMMARY OF THE INVENTION 
     Disclosed are embodiments of a seating unit convertible between a seating configuration and a sleeping configuration. In a version, the seating unit may include a base configured to rest on an underlying surface, a back frame pivotally connected to the base, a back deck connected to the back frame, a mid-frame pivotally connected to the base, a mid-deck connected to the mid-frame, a seat frame pivotally connected to the mid-frame, and a seat deck connected to the seat frame. In the sleeping configuration the mid-deck may lie within a first horizontal plane, the back deck may lie within a second horizontal plane, and the seat deck may lie within a third horizontal plane. The first horizontal plane may be at a first elevation, the second horizontal plane may be at a second elevation which is lower than the first elevation, and the third horizontal plane may be at a third elevation which is lower than the second elevation. The vertical distance between the first and second horizontal planes may be less than a vertical distance between the first and third horizontal planes. 
     The seating unit may further include a first cushion connected to the back deck, a second cushion connected to the mid-deck, and a third cushion connected to the seat deck. In the sleeping configuration the first cushion may have a relative vertical thickness that is greater than a vertical thickness of the second cushion and less than a vertical thickness of the third cushion. A crest of the first cushion, a crest of the second cushion, and a crest of the third cushion may all lie within a fourth horizontal plane. Further, respective sleeping surfaces of the first, second, and third cushions may be arcuate. In the sleeping configuration, the vertical thickness of the third cushion may be greater than the vertical thicknesses of the first and second cushions. Also, in the seating configuration the mid-deck and second cushion may be folded under the seat deck and third cushion. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  is a perspective view of a convertible chair of the prior art with the bed shown in the folded/chair configuration; 
         FIG. 1B  is a side section view of the convertible chair of  FIG. 1A  shown in the unfolded/sleeper configuration; 
         FIG. 2A  is a perspective view of an embodiment of a convertible seat in its seat configuration; 
         FIG. 2B  is a perspective view of the convertible seat of  FIG. 2A  with its front being lifted from the seat configuration; 
         FIG. 2C  is a perspective view of the convertible seat of  FIG. 2A  in an intermediate position; 
         FIG. 2D  is a perspective view of the convertible seat of  FIG. 2A  in a bed configuration; 
         FIG. 3  illustrates an embodiment of noncoplanar deck sections of a convertible seat; 
         FIG. 4  illustrates an embodiment of cushions supported by the noncoplanar deck sections illustrated in  FIG. 3 ; 
         FIG. 5  is an exploded view of frame components of an embodiment of a convertible seat; 
         FIG. 6A  is a rear perspective view of an embodiment of a back cushion assembly for a convertible seat; 
         FIG. 6B  is a side elevational view of the back cushion assembly of  FIG. 6A ; 
         FIG. 6C  is a rear elevational view of the back cushion assembly of  FIG. 6A ; 
         FIG. 6D  is a top plan view of the back cushion assembly of  FIG. 6A ; 
         FIG. 7A  is a top perspective view of an embodiment of a seat cushion assembly for a convertible seat; 
         FIG. 7B  is a side elevational view of the seat cushion assembly of  FIG. 7A ; 
         FIG. 7C  is a top plan view of the seat cushion assembly of  FIG. 7A ; 
         FIG. 7D  is an inverted rear elevational view of the seat cushion assembly of  FIG. 7A ; 
         FIG. 7E  is a bottom plan view of the seat cushion assembly of  FIG. 7A ; 
         FIG. 8A  is a rear perspective view of an embodiment of a mid-seat cushion assembly for a convertible seat; 
         FIG. 8B  is a side elevational view of the mid-seat cushion assembly of  FIG. 8A ; 
         FIG. 8C  is a rear elevational view of the mid-seat cushion assembly of  FIG. 8A ; 
         FIG. 8D  is a top plan view of the mid-seat cushion assembly of  FIG. 8A ; and 
         FIG. 8E  is a front elevational view of the mid-seat cushion assembly of  FIG. 8A . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The present invention will be described more particularly hereinafter with reference to the accompanying drawings. The invention is not intended to be limited to the illustrated embodiments; rather, these embodiments are intended to fully and completely disclose the invention to those skilled in this art. In the drawings, like numbers refer to like elements throughout. Thicknesses and dimensions of some components may be exaggerated for clarity. Well-known functions or constructions may not be described in detail for brevity and/or clarity. 
     In addition, spatially relative terms, such as “under”, “below”, “lower”, “over”, “upper” and the like, may be used herein for ease of description to describe one element or feature&#39;s relationship to another element(s) or feature(s) as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “under” or “beneath” other elements or features would then be oriented “over” the other elements or features. Thus, the exemplary term “under” can encompass both an orientation of over and under. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly. 
     The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. As used herein the expression “and/or” includes any and all combinations of one or more of the associated listed items. 
     Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein. 
     By way of introduction, a convertible seat is adapted for use in applications from recreational vehicles to healthcare, commercial and residential applications. The convertible seat (hereinafter sometimes referred to as “mechanism” or “unit”) reduces the number of steps required to position the unit from the chair/seat configuration to a bed/sleeper configuration. The convertible seat consists of seat and mid seat sections that are attached via a set of articulating linkage which, when the seat front is lifted and pulled up/outward, begin to extend and position support legs without secondary motion by the user. Once the legs of the now extended seat are supported by the floor the back section is rotated forward, completing conversion of the mechanism from the seat to the bed configuration. 
     An extendable and flip-over convertible seat has a base, a back frame, a seat frame, a mid-seat frame and linkage operatively connecting the frames to one another. The back frame is pivotally connected to the base so that it rotates from a seat configuration aligned slightly back from vertical, to a bed configuration in which the top is pulled forward to a horizontal position, whereby the back of the back frame (corresponding to the seat configuration) is now flat and upwardly facing. 
     Cross members are affixed to the respective frames so as to complete a seat deck, mid-seat deck and back deck. The seat frame and the mid-seat frame are pivotally connected to one another such that in a seat configuration the seat deck has the mid-seat deck folded thereunder. 
     Preferably, when the seat deck and mid-seat deck are folded and in the seat configuration the seat deck positively engages and locks the back deck. 
     In order to convert to a bed configuration in which the seat deck and the mid-seat deck form an extended first bed assembly (i.e., in use to support a person&#39;s trunk and legs), the seat deck is lifted up by its front edge and then frontwardly extended to an intermediate position. The linkage moves the mid-seat deck from an unseen location below the seat deck to an exposed, substantially horizontal orientation. 
     A support leg, or preferably a pair, are pivotally connected to the front edge of the seat deck and connected by a link mechanism to the base frame whereby the legs transition from a folded position to an extended position simultaneously as the first bed assembly (the seat deck and mid-seat deck combination) is extended to and through the intermediate position and then downward to the bed configuration. The leg(s) support the front edge in the bed configuration. This articulating leg/linkage assembly reduces the number of operations required by a user to convert the convertible seat from a seat configuration to a bed configuration as a mid-deck section emerges for underneath the seat deck. The mid-deck has a base that supports a cushion. In the bed configuration the mid-deck is within a plane that is non-coplanar with the extended seat deck and back deck. 
     The back deck has a seat back surface facing frontward when in the seat configuration and a lying/sleeping surface opposite, facing rearward, when in the seat configuration. After extending the seat deck and mid-seat deck into the first bed assembly the back deck may be pivoted (top moved forward and down) from the seat position to the bed position. The seat back (frontwardly facing) surface faces downwardly and the sleeping surface (the back of the seat back when in the seat position) faces upwardly to define a second bed assembly. The first bed assembly and the second bed assembly complete the bed. 
     As described below, in order to adapt to compactness and seating comfort requirements and support for lying/sleeping wherein a person&#39;s mass is not evenly distributed, the decks, in the bed configuration are aligned at different heights—in different planes. The mid-seat deck is highest, the back deck slightly lower and the seat deck considerably lower. This also accommodates different thicknesses and densities in the respective seat cushions. 
     The relative heights of the decks and corresponding thicknesses of the cushions provide a unique and comfortable support surface for supporting a person&#39;s mass when lying on the bed. In the lying/sleeping configuration, a person&#39;s trunk is their center of mass and is, in a vast majority of bodily shapes, the heaviest part of the body. In an embodiment, with the unit in the lying/sleeping configuration (hereinafter referred to as the sleeping configuration, although not limited to use for just sleeping), the mid-seat deck is highest and its cushion thinnest (relative to those of the seat deck/cushion and back deck/cushion), to thereby provide a first robust support surface for a person lying on the bed. The back deck/cushion supports a person&#39;s upper torso, arms, and head (usually the second heaviest part of the body) to provide a second robust support surface for a person lying on the bed. And the seat deck/cushion supports a person&#39;s legs in the sleeping configuration and provides a comfortable support surface there for, as well as in conjunction with the thickest of the three cushions, a soft seating surface for the unit when in the seating configuration. In an embodiment, the cushion for the back deck is thinner than the cushion for the seat deck, but thicker than the cushion for the mid-seat deck. 
     The particular cushions are formed and arranged to provide advantageous and comfortable seating and sleeping surfaces. A cushion is mounted on the seating surface having a flat bottom on the deck and a top arcuate surface. A plane intersecting the crest of the cushion&#39;s arcuate surface defines a first plane. The mid-seat deck has a cushion that, when the seat is in the seating position, is unused, while in the sleeping position a person&#39;s center of mass may well rest on the mid-seat deck cushion. Thus, the mid-deck cushion has its own thickness and density with a flat bottom (in the sleeping position) and an arcuate top surface. In the sleeping configuration a plane intersecting the crest of the arcuate surface of the mid-seat deck cushion defines a second plane. Finally, the back deck sleeping surface has a third cushion having a flat bottom on the deck and an arcuate surface. A plane intersecting the crest of the arcuate surface of this cushion defines a third plane. The first, second, and third planes are co-planar, but the particular cushion thicknesses are, as described above, different. 
     The sleep surface of this bed unit has extra padding added and is contoured in a manner that even with its thin profile, provides a comfortable sleep surface without the need for an air mattress, such as those required for like furniture. The sleep surface can be tailored in any material desired to meet customer expectations. 
     With the contour profile and extra padding added to the sleep surface the user is able to easily use the unit as a bed without the need for additional products, such as an air mattress. If desired, however, a user may also set an air mattress over the sleep surface. 
     The arcuate surfaces are preferably formed by affixation of a fabric or sheet material over an elastomeric material, such as a foam, which foam may be formed either as a curvilinear surface for the mid and back decks or as a pyramidal frustum for the seat. The combination of fabric and foam permits formation of the pyramidal frustum using combined planar surfaces, four angled and a fifth flat while the upholstery procedure of stretching the fabric or sheet produces the final arcuate surface. 
     As can be seen in the drawings (discussed below) the cushions are formed so as to have extending flanges at the perimeters and additionally have filler pieces. These configurations provide a combination of properties including edge support and better fit on the respective frames. The cushions preferably cover the frames to avoid contact with a user and also reduce the occurrence of chaffing the bedding. 
     Referring now to  FIGS. 2A-2D , an embodiment of a convertible seat  20  is illustrated. The convertible seat  20  is illustrated in the seat ( FIG. 2A ), transitional ( FIGS. 2B and 2C ), and bed ( FIG. 2D ) configurations. The convertible seat  20  includes a seat  22 , a back rest  24 , and a mid-section  26 . In order to convert the convertible seat  20  to a bed in which the seat  22  and mid-seat  26  form an extended first bed assembly, the seat  22  is lifted up by its front edge (illustrated in  FIGS. 2A and 2B ) and then frontwardly extended to an intermediate position ( FIG. 2C ). Linkage moves the mid-seat  26  from an unseen location below the seat  22  to an exposed, substantially horizontal orientation. The back  24  in the seat configuration ( FIG. 2A ) is aligned slightly back from vertical and is flipped forward to a bed configuration ( FIG. 2D ) in which the top is pulled forward to a horizontal position. 
       FIG. 3  illustrates an embodiment of deck sections  30  of a convertible seat in the sleeper configuration. The deck sections  30  may be provided in a convertible seat such as the one illustrated in  FIGS. 2A-2D . The illustrated deck sections  30 , or variations thereof, may be provided in other types and configurations of convertible chairs or sofas, as examples. In the bed configuration, the seat deck  32  is at a lowest relative elevation, the mid-deck  34  is at a highest relative elevation, and the back deck  36  is at an intermediate elevation. The decks are supported by a frame (an embodiment of which is illustrated in  FIG. 5 ) having legs  38 (A),  38 (B), and  38 (C). The seat deck  32  lies within a first plane, the mid-deck  34  lies within a second plane, and the back deck  36  lies within a third plane. A relative vertical distance between the three planes is represented by A, B, and C in  FIG. 3 . 
       FIG. 4  illustrates an embodiment of cushions supported by the deck sections, such as those illustrated in  FIG. 3  as an example. A seat cushion  42  rests on or is fixed to the seat deck  32  and has a thickness represented by D. A mid-cushion  44  rests on or is fixed to the mid-deck  34  and has a thickness represented by E. A back cushion  46  rests on or is fixed to the back deck  36  and has a thickness represented by F. The thicknesses of the cushions  42 ,  44 , and  46 , in conjunction with the relative elevations of the decks  32 ,  34 , and  36  provide a flat or substantially flat sleeping surface. Other embodiments are contemplated. For example, the thickness of the mid-cushion  44  may be slightly thicker than that illustrated in  FIG. 4 , providing additional or elevated lumbar support. In other embodiments, relative elevations of the decks and relative thicknesses of the cushions may be other than those illustrated. 
       FIG. 5  is an exploded view of frame components  50  of an embodiment of a convertible seat. The back frame  54  is shown upright (in the “seat” configuration) and pivots forward (corresponding to the movement illustrated in  FIGS. 2C and 2D ) about pivot points referred to as “A 1 ” and “A 2 ”. The frame components  50  further include a base support assembly (also referred to as a base frame)  52 , a mid-frame  56 , and a seat frame  58 . The back frame  54 , mid-frame  56 , and seat frame  58  may support a back deck, mid-deck, and a seat deck, respectively. Respective cushions may rest on or be fixed to the back deck, mid-deck, and seat deck (not shown). The illustrated embodiment of the base support assembly  52  includes frame elements, including linkage, that enable the convertible bed to transition between a chair and a bed, such as the conversion illustrated in  FIGS. 2A to 20 , as an example. The back frame  54 , mid-frame  56 , and seat frame  58  are supported by and attached to the base support assembly  52 . The base support assembly  52  is configured to rest on an underlying surface, such as a floor. 
     In  FIG. 5 , the mid-frame  56  and the seat frame  58  are illustrated (as an exploded view) in the bed configuration (for example, corresponding to the convertible chair of  FIGS. 2C and 2D ). In the bed configuration, having the back frame  54  rotated forward and down, the base support assembly  52  supports the mid-frame  56 , the back frame  54 , and the seat frame  58  within highest, mid, and lowest planes, respectively, corresponding to the heights of the decks illustrated in  FIG. 3 , as an example. The bed is converted into a seat by rotating the back frame  54  up and back, into the illustrated position, and lifting seat frame  58 , causing the mid-frame  56  to pivot up and backwards (i.e., clockwise in the figure) about pivot points “B 1 ” and “B 2 ” as the mid-frame  56  flips under the seat frame  58  about points “C 1 ” and “C 2 ” (i.e., clockwise in the figure). The seat frame  58  is then urged into the seat configuration (corresponding to the movement illustrated by  FIGS. 2C to 2B to 2A , as an example). 
     As discussed above, the particular cushions are formed and arranged to provide advantageous seating and sleeping surfaces. A back deck sleeping surface has a first cushion having a flat bottom on the deck and an arcuate surface. The back deck sleeping surface faces rearward when the back deck is set in the seating configuration. 
       FIG. 6A  is a rear perspective view of an embodiment of a back cushion assembly  60  for a convertible seat.  FIG. 6B  is a side elevational view of the back cushion assembly  60 .  FIG. 6C  is a rear elevational view of the back cushion assembly  60 . And  FIG. 6D  is a top plan view of the back cushion assembly  60 . 
     The back cushion assembly  60  preferably includes a backing  62 , filler  64 , a main taper  66 , and a fillers taper  68 . The back cushion assembly  60  preferably has an arcuate top/sleeping surface. With the convertible seat in the bed configuration, a first cushion plane intersects the crest of the arcuate surface of the back cushion assembly  60 . 
     A cushion is mounted on the seating surface having a flat bottom on the deck and a top arcuate surface.  FIG. 7A  is a top perspective view of an embodiment of a seat cushion assembly  70  for a convertible seat.  FIG. 7B  is a side elevational view of the seat cushion assembly of  FIG. 7A .  FIG. 7C  is a top plan view of the seat cushion assembly of  FIG. 7A .  FIG. 7D  is an inverted rear elevational view of the seat cushion assembly of  FIG. 7A . And  FIG. 7E  is a bottom plan view of the seat cushion assembly of  FIG. 7A . 
     The seat cushion assembly  70  preferably includes a main body  72  between filler  74  and a top lam  75 . The sides of the seat cushion assembly are defined by left and right side lams  76 A and  76 B. The seat cushion assembly  70  further includes backing  79  and a cut main poly  78 . With the convertible seat in the bed configuration, a second cushion plane intersects the crest of the arcuate surface of the seat cushion assembly  70 . 
     The mid-seat deck has a cushion that, when the seat is in the seating position, is unused. In the sleeping position a person&#39;s center of mass may well rest on the mid-seat deck cushion. Thus, the cushion has its own thickness and density with a flat bottom and an arcuate top surface.  FIG. 8A  is a rear perspective view of an embodiment of a mid-seat cushion assembly  80  for a convertible seat.  FIG. 8B  is a side elevational view of the mid-seat cushion assembly  80  of  FIG. 8A .  FIG. 8C  is a rear elevational view of the mid-seat cushion assembly  80  of  FIG. 8A .  FIG. 8D  is a top plan view of the mid-seat cushion assembly  80  of  FIG. 8A . And  FIG. 8E  is a front elevational view of the mid-seat cushion assembly  80  of  FIG. 8A . The mid-seat cushion assembly preferably includes a main body  82 , backing  84 , and left and right lams  86 A and  86 B. With the convertible seat in the bed configuration, a third cushion plane intersects the crest of the arcuate surface. 
     Preferably, the first, second, and third cushion planes (corresponding to the base frames) are co-planar, but the particular arcuate surfaces and cushion thicknesses are different. 
     The arcuate surfaces of the cushions may be formed by affixation of a fabric or sheet material over an elastomeric material, such as foam, which foam may be formed either as a curvilinear surface, for the mid and back cushions, or as a pyramidal frustum for the seat cushion. The combination of fabric and foam permits formation of the pyramidal frustum using combined planar surfaces, four angled and a fifth flat while the upholstery procedure of stretching the fabric or sheet produces the final arcuate surface. 
     As illustrated in the drawings, the cushions may be formed so as to have extending flanges at the perimeters and additionally have filler pieces where shown. These configurations provide a combination of properties including edge support, better fit on the respective frames and covering the frames to avoid contact with persons and reduce chafe on bedding. 
     The foregoing is illustrative of the present invention and is not to be construed as limiting thereof. Although exemplary embodiments of this invention have been described, those skilled in the art will readily appreciate that many modifications are possible in the exemplary embodiments without materially departing from the novel teachings and advantages of this invention. Accordingly, all such modifications are intended to be included within the scope of this invention as defined in the claims. The invention is defined by the following claims, with equivalents of the claims to be included therein.