Patent application title: Control for adjustable backrest of a seat or lounge, and seat or lounge incorporating it
John W. Caldwell (So. Pasadena, CA, US)
IPC8 Class: AA47C740FI
Class name: Movable back tiltable plural distinct occupant-supporting positions
Publication date: 2009-05-21
Patent application number: 20090127909
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.
1. In an article of furniture having a base and a backrest that is
tiltedly adjustably attached to the base at a first hinge point, a
control to enable placing the backrest at a selected angle restrained
against backward movement, and enabling the backrest to be moved to a
retracted, flat position, said control comprising:a rigid drive arm
rigidly fixed to the backrest for rotation with the backrest around said
first hinge point, said drive arm having a free end:a rigid latch arm
having a hinged end hingedly attached to the free end of the drive arm,
and a follower end distant from the hinged end; anda body providing a
loop-shaped track, said track including an adjustment segment, a return
segment, a divider between said adjustment segment and return segment, a
divider separating said adjustment segment and return segment, a
transition segment between both ends of said adjustment segment and
return segment; and a plurality of stops along said adjustment segment;
anda biased selector in one of said transition segments permitting said
follower to move from said adjustment segment into said return segment,
but not the reverse after the backrest has reached its uppermost
position, whereby raising the backrest moves the follower end along the
stops, permitting raising movement but limiting lowering movement, and
having fully raised the free end moves past the selector into the return
segment to return to the adjustment segment when the backrest is fully
2. Apparatus according to claim 1 in which said control is bilateral, being located at each side of the base with the drive arm and latch arm being disposed between the sides of the base.
3. Apparatus according to claim 2 in which said first hinge point and said stops are fixed to said base, spaced apart in elevation, with the hinge between said arms being located such as to form a three link arrangement in which lowering of the backrest is resisted by a compressive force on the latch arm.
4. Apparatus according to claim 2 in which said latch arm engages stops at both sides of the base.
5. Apparatus according to claim 4 in which said stops comprise shoulders abutted by follower end when said back rest is pressed backwardly when the follower ends are disposed on said adjustment segment.
FIELD OF THE INVENTION
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
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.
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.
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.
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
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.
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.
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.
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.
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.
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.
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
FIG. 1 is an off-axis view of the presently-preferred embodiment of the invention with the backrest in its lowered position;
FIG. 2 is a view similar to FIG. 1 with the backrest in an intermediate raised position, restrained against backward movement;
FIG. 3 is a view similar to FIG. 1 with the backrest moved beyond its uppermost position prior to being lowered;
FIG. 4 is a top plan view of the base;
FIG. 5 is an enlarged view of a portion of FIG. 1; and
FIG. 6 is a force diagram showing the means to restrain the backrest.
DETAILED DESCRIPTION OF THE INVENTION
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
Any desired support for the occupant can be applied to the base and the backrest, such as woven cloth or plastic sheeting.
Accordingly this invention provides an elegant adjustment for a backrest which is adjustable merely by manipulating the backrest, is attractive, and is easily stored.
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.
Patent applications by John W. Caldwell, So. Pasadena, CA US
Patent applications in class Plural distinct occupant-supporting positions
Patent applications in all subclasses Plural distinct occupant-supporting positions