Abstract:
An article of furniture such as a chair or lounge with an adjustable back. A control enables the angle of the back to be upwardly adjusted or laid flat, merely by appropriately tilting the backrest.

Description:
FIELD OF THE INVENTION 
       [0001]    A control and an article of furniture which incorporates the control. The article of furniture is such as a chair or lounge and includes a pivoted backrest that can be raised to a plurality of selectable angles, retained at a selected angle, and released to allow the backrest to be raised further and thereafter lowered, all without requiring the user to manipulate anything except the backrest itself, and without requiring struts to support the backrest. 
       BRIEF DESCRIPTION OF THE INVENTION 
       [0002]    A chair or chaise lounge often has a backrest which can be laid flat or raised to some selectable angle. Such furniture is well-known and often is employed outdoors such as adjacent to a swimming pool. This furniture is generally lightweight and preferably is stackable for storage. 
         [0003]    Adjustment of the backrest frequently employs ratchet-like structures into which struts from the backrest fit. Generally they are spring or weight loaded so as to assure engagement. Release of the engagement may be relatively easy when raising the backrest, but require the user to push or otherwise manipulate the strut or even a lock, in order to lower the backrest for storage or for readjustment. This requires the occupant to change his or her location to do it, and risks putting the hands in a pinch. For leisure use, especially in elegant places, it required movement or manipulation which preferably would be unnecessary. 
         [0004]    It is an object of this invention to provide a backrest control that enables the user to raise the backrest, even while seated on the furniture, to a desired angle by moving the backrest upwardly. Reverse movement at this time will be prevented by the control, which has numerous points of engagement to provide for various angles of the backrest. 
         [0005]    After the backrest has passed its uppermost selectable position, the control importantly enables the backrest to be fully lowered to its flat position without restraint on the way down or manipulation of anything except the backrest itself. Thereafter the backrest may again be raised to any selectable position. The only action required by the user was to fully raise the backrest and then lower it to its flat position, after which the backrest can again be raised to a desired angle, or left flat for storage. It is quick and easy. 
       BRIEF DESCRIPTION OF THE INVENTION 
       [0006]    An article of furniture such as a chair or lounge includes a base for a seat or lounge and a backrest pivotally mounted to the base at each side. The backrest may be lowered flat to extend the lounge for its full length as a couch, and raised to a number of selectable angles for the occupant to lean against as a chair or demi-lounge. The base is preferably configured for stacking while the backrest is fully lowered. 
         [0007]    A control is provided to enable the backrest to be retained in a selected upper position, and readily to be lowered to its flat position. The control is engaged by a linkage that is drivingly rotatably connected to the backrest. This linkage includes a drive arm drivingly connected to the backrest and a latch arm hingedly mounted to the drive arm. The backrest and the drive arm act in the manner of a bellcrank as will be discussed below. The latch arm includes a follower at its end removed from the hinge pivot. 
         [0008]    The control includes a loop-shaped track having an adjustment segment, a return segment, and a first and second transition segment. The transition segments connect adjacent ends of the adjustment and return segments to complete the loop. 
         [0009]    The adjustment segment includes a progression of stops unidirectionally engageable with the follower. The return segment enables the free movement of the backrest in both directions so the backrest can return to its flat orientation. 
         [0010]    A biased selector in the transition segment at the backrest-raised setting enables the movement of the follower from the adjustment segment to the return segment, but prevents the reverse. 
         [0011]    Accordingly the backrest can be lowered by first raising it fully, and then lowering it. Reverse movement is prevented while the latch arm is in the adjustment segment, and the user will reliably be supported. 
         [0012]    The above and other features of this invention will be fully understood from the following detailed description and the accompanying drawings, in which: 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]      FIG. 1  is an off-axis view of the presently-preferred embodiment of the invention with the backrest in its lowered position; 
           [0014]      FIG. 2  is a view similar to  FIG. 1  with the backrest in an intermediate raised position, restrained against backward movement; 
           [0015]      FIG. 3  is a view similar to  FIG. 1  with the backrest moved beyond its uppermost position prior to being lowered; 
           [0016]      FIG. 4  is a top plan view of the base; 
           [0017]      FIG. 5  is an enlarged view of a portion of  FIG. 1 ; and 
           [0018]      FIG. 6  is a force diagram showing the means to restrain the backrest. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0019]    A lounge  20  according to this invention includes a base  21  and a backrest  22 . These may be formed from segments and assembled lengths of metal tubing or any other suitable material of construction. The arrangement of the structural members is of on special importance. 
         [0020]    The base includes side runners  23 , 24  joined by cross-ties  25 , 26 , 27 , 28 . The side runners are each formed by two segments, which do not directly interconnect. Segments  30  and  31  define the edges of “bed” part  32  of the lounge. It is on this bed part that the occupant sits or reclines. 
         [0021]    Segments  33  and  34  define the edges of the “base” part  35 , which extends rearwardly of the bed part to support the weight of the occupant laying on the reclined lounge, or resisting the torque from the rearward force of a person resting on the raised backrest. 
         [0022]    Segments  30  and  33 , and  31  and  34  are not directly connected, but are structurally joined.  FIG. 4  illustrates that these segments  30  and  31  and segments  33  and  34  are welded to cross tie  27  and segments  33  and  34  are welded to cross tie  28 . These provide a continuous side rail, but segments  33  and  34  are not in the same horizontal plane as segments  30  and  31 . Instead they are lower, so as to accommodate the backrest when it is fully laid back. 
         [0023]    Legs  40  and  41  are identical to each other, on opposite sides of the lounge. Each has base portions  42 , 43  end risers  44 , 45 , and a mid-riser  46 . The legs are attached to the side runners and to the cross ties at the risers. Preferably the legs depend from the side runners at an obtuse angle so the lounge can be stacked. 
         [0024]    Backrest  22  is hingedly attached to the base at both of the side runners. It comprises edge formers  50 , 51 , joined by cross-ties  52 , 53 , 54  to form a rigid frame. A hinge plate  56  at each side hingedly joins the backrest to the base for up and down angular movement around hinge axis  60  (at each side). It is the object of this invention to enable this backrest to be raised to a desired angle, and also readily to be retained to a level alignment. 
         [0025]    The means to provide this adjustability is a control  70  preferably provided at both sides of the frame. When used as a pair, controls on the opposite side are mirror images. The description of one will be identical to the other. 
         [0026]    Control  70  is a plate rigidly mounted to the base. As best shown in  FIG. 5  it forms as a recess a loop-shaped track  75  providing in its boundary walls a group of interactive structural elements. 
         [0027]    Track  75  comprises an adjustment segment  76 , a return segment  77 , a transition segment  78  at one adjacent end of each segment, and another transition segment  79  at the other end. 
         [0028]    A unidirectionally biased latch  80  permits movement in one direction and not in the other, as will later be described between the adjustment segment and the return segment prevents a follower to be described from crossing from one segment to the other except through the transition segments. 
         [0029]    The adjustment segment includes a plurality of stops  81  which act to restrain backward movement of the backrest under certain circumstances. Return segment  77  presents no impediment to movement in either direction. 
         [0030]    The control further includes a linkage  90  interposed between the base and the control. A drive arm  91  acts in the manner of a bellcrank. It is a rigid link  92  but is provided in a number of pieces, as will be described. The center of rotation of link  92  is hinge axis  60  where the backrest is hinged to the base. 
         [0031]    Link  92  is connected to a cross-tie  52  of the backrest, which in turn is rigidly connected to a hinge plate  50 . Hinge plates  56  are pivotally mounted to segments  23  and  24 . 
         [0032]    A rigid latch arm is hingedly attached to drive arm  91  at hinge axis  60 . As an integral part of latch arm  100 , a follower  101  is a rod  102  with follower tips  103 , 104 , one at each end. These tips ride in the loop shaped tracks of the control. 
         [0033]    The control is shown in its most elegant presentation. It is entirely inside the “envelope” of the furniture, and is equally supported at both sides. If desired, the control feature would only have to be used on one side, but this arrangement with control at both sides gives maximum assurance. 
         [0034]    As will be seen, manipulation of the backrest will cause the follower to move in the track segments for adjustable positioning of the backrest, and lowering of it for storage or use as a couch. 
         [0035]    The operation of the device is somewhat counter intuitive, because the restraint on the backward tilting of the backrest is exerted in a forward direction instead of backwardly as one encounter with a typical strut device. This control does not use a strut, but rather a bell crank arrangement which reverses the direction of force. 
         [0036]    Also the structural integrity is not that of a simple strut, but rather that of a three link system removed from the backrest, one of its lengths being selectable. 
         [0037]      FIG. 6  is a schematic side elevation whose objective is to show the relative location in side elevation of the hinge points, the followers, and the stops. Notice that the backrest and the drive arm are unitary and hinged around axis  60 . Notice hinge point  87  between the drive arm  81  and latch arm  90 . This forms a rigid three link structure which will prevent further lowering of the backrest while the follower is in the adjustment segment. 
         [0038]    In reverse direction, namely for raising the backrest, the follower readily moves to the left in  FIGS. 1 and 2  for a purpose now to be described. 
         [0039]    In  FIG. 1 , the backrest is flat and the follower is well to the right in this Fig. When it is raised, as shown in  FIGS. 2 and 3 , the follower passes along the stops, and the backrest can be stopped at any one of them and can reliably be used at that angle. 
         [0040]    Suppose the user now wants to lower the backrest. It cannot be done directly because the stops will prevent it. Instead the backrest must be fully raised. When this occurs it will pass the selector (which allows it to pass, but not to return). Then with the follower in the return segment the backrest can be fully lowered to the position of  FIG. 1 . It can be left there for storage, or raised again to a selected angle. 
         [0041]    Any desired support for the occupant can be applied to the base and the backrest, such as woven cloth or plastic sheeting. 
         [0042]    Accordingly this invention provides an elegant adjustment for a backrest which is adjustable merely by manipulating the backrest, is attractive, and is easily stored. 
         [0043]    This invention is not to be limited by the embodiment shown in the drawings and described in the description, which is given by way of example and not of limitation, but only in accordance with the scope of the appended claims.