U.S. patent application number 12/390453 was filed with the patent office on 2009-06-11 for reclining lounge chair.
Invention is credited to Thomas Rudolf Schneider.
Application Number | 20090146468 12/390453 |
Document ID | / |
Family ID | 37697544 |
Filed Date | 2009-06-11 |
United States Patent
Application |
20090146468 |
Kind Code |
A1 |
Schneider; Thomas Rudolf |
June 11, 2009 |
Reclining Lounge Chair
Abstract
An improved reclining lounge chair is described, which comprises
a footrest that is pivotally connected to a center seat member by a
footrest attachment axle, and in which the footrest position is
controlled by a footrest lift mechanism. While the lounge chair is
its non-reclined upright position the footrest is oriented
approximately vertical. In this approximately vertical orientation
the footrest doesn't extend significantly forward of the center
seat member, thus allowing an occupant easy access to the chair
from the front. In its fully reclined position the footrest rotates
into an approximately horizontal orientation, providing a
comfortable reclined position.
Inventors: |
Schneider; Thomas Rudolf;
(Bad Neustadt, DE) |
Correspondence
Address: |
Smartpat PLC
1785 BRADFORD RD.
BIRMINGHAM
MI
48009
US
|
Family ID: |
37697544 |
Appl. No.: |
12/390453 |
Filed: |
February 21, 2009 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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PCT/EP2007/006864 |
Aug 2, 2007 |
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12390453 |
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Current U.S.
Class: |
297/75 |
Current CPC
Class: |
A47C 1/0342 20130101;
A47C 4/12 20130101; A47C 1/143 20130101 |
Class at
Publication: |
297/75 |
International
Class: |
A47C 1/02 20060101
A47C001/02 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 22, 2006 |
DE |
10 2006 039 278.7 |
Claims
1. A reclining lounge chair, comprising: a center seat member; a
backrest, the backrest being operatively connected to the center
seat member; a footrest, the footrest being pivotally connected to
the center seat member by a footrest attachment axle; wherein the
center seat member, the backrest, and the footrest form a seat
assembly, which is pivotally connected to a base frame by a seat
attachment axle at the center seat member, and wherein the seat
assembly may rotate about the seat attachment axle between an
upright position and a fully reclined position without changing the
relative alignment of backrest and center seat section; a footrest
lift mechanism, the front end of the footrest lift mechanism being
pivotally connected to the footrest by a front footrest lift axle,
and the rear end of the footrest lift mechanism being pivotally
connected to the base frame by a rear footrest lift axle; wherein
the rear footrest lift axle is located below the seat attachment
axle, and wherein the footrest lift mechanism causes the footrest
to rotate about the footrest attachment axle by more than
60.degree. but less than 125.degree. when the seat assembly is
rotated from the upright position to the fully reclined
position.
2. The reclining chair as in claim 1, wherein the footrest rotates
by more than 80.degree. about the footrest attachment axle when the
seat assembly is rotated from the upright position to the fully
reclined position.
3. The reclining chair as in claim 1, wherein the footrest rotates
by less than 100.degree. about the footrest attachment axle when
the seat assembly is rotated from the upright position to the fully
reclined position.
4. The reclining chair as in claim 1, wherein the rear footrest
lift axle is located forward of the seat attachment axle.
5. The reclining chair as in claim 1, wherein the rear footrest
lift axle is located below the seat attachment axle.
6. The reclining chair as in claim 1, wherein during regular use
the backrest is at a predetermined, fixed angle relative to the
center seat member, and wherein the backrest can be folded onto the
center seat member to assume a storage position.
7. The reclining chair as in claim 1, wherein the rear footrest
lift axle is located above the seat attachment axle.
8. The reclining chair as in claim 1, wherein the front footrest
lift axle is forward of the footrest attachment axle while the
chair is in its upright position.
9. The reclining chair as in claim 1, wherein the front footrest
lift axle is rearward of the footrest attachment axle while the
chair is in its fully reclined position.
10. The reclining chair as in claim 1, wherein the distance between
the seat attachment axle and the rear footrest lift axle is less
than 15% of the height of the seat attachment axle from the
floor.
11. The reclining chair as in claim 1, wherein the distance between
the footrest attachment axle and the front footrest lift axle is
less than 15% of the height of the seat attachment axle from the
floor.
12. The reclining chair as in claim 1, wherein the front footrest
lift axle is at a height between the footrest attachment axle and
the floor.
13. The reclining chair as in claim 1, wherein the base frame
comprises two base frame members, one of which is located left of
the seat assembly and one of which is located right of the seat
assembly, and wherein the footrest lift mechanism comprises two
footrest lift bars, which are located inside of and adjacent to
each of the two base frame members.
14. The reclining chair as in claim 1, further comprising a latch
mechanism, which latches the chair in one of two or more
predetermined reclining positions.
15. The reclining chair as in claim 14, wherein the latch mechanism
is located between two parts of the chair that rotate relative to
each other while reclining.
16. The reclining chair as in claim 14, wherein the latch mechanism
is located on the inside of the base frame around the rear footrest
lift axle.
17. The reclining chair as in claim 14, wherein the latch mechanism
comprises a latch disk with alternating radially aligned
protrusions and recesses that is attached torsionally rigid to the
base frame, and a sliding element which rotates about the disk's
center axis, wherein the sliding element comprises at least one
protrusion, which is pushed into the latch disk by a latch
spring.
18. The reclining chair as in claim 17, comprising two or more
identical protrusions and recesses.
19. The reclining chair as in claim 17, comprising two or more
protrusions and recesses which are different in at least one of
size, width, and slope angle.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This is a continuation of international patent application
PCT/EP2007/006864, filed Aug. 2, 2007, which designated the United
States, and which claimed priority to German patent application No.
10 2006 039 278.7, filed Aug. 22, 2006. These applications are
hereby incorporated by reference.
TECHNICAL FIELD
[0002] The present invention generally relates to a reclining
lounge chair, and more particularly, to a reclining lounge chair
comprising a footrest lift mechanism.
BACKGROUND OF THE INVENTION
[0003] Lounge chairs, which can be adjusted between an upright
position and a reclined position, are well known. A
category-defining reclining lounge chair is described in FR 635,465
A. This known chair comprises a footrest, which is connected to a
seat by a horizontal pivot axis. An adjusting lever mechanism is
provided, which is pivotally supported by a horizontal support axle
relative to the frame. The opposite end of the adjusting lever
mechanism is pivotally supported by the footrest through a
horizontal support axle.
[0004] A reclining lounge chair comprising a seat, a backrest, and
a footrest, is described in EP 0,358,666 B1, invented by the same
inventor hereof. The backrest is pivotally joined to the seat by a
horizontal axle, and the seat is pivotally joined to the footrest
by a horizontal axle, respectively. Thereby, the seating and lounge
chair can be folded, such that the footrest, the seat, and the
backrest are located essentially parallel to each other.
[0005] The reclining lounge chair of EP 0,358,666 can be adjusted
into a semi-reclined lounge position, in which the backrest points
upward and rearward, extending from the rear end of the seat. The
footrest points downward and forward from the front end of the seat
towards the floor. From this position the lounge chair can be
adjusted into a fully reclined sleeping position, in which
footrest, seat, and backrest are essentially located in a
continuous horizontal plane. This style of reclining lounge chairs
has been well accepted in the market.
[0006] In variation therefrom other reclining lounge chairs exist.
Reclining lounge chairs are known, which comprise an integral couch
frame comprising a center seat section, a backrest section, and
footrest section. In such chairs the backrest section is positioned
at a fixed predetermined small angle relative to the center seat
section, and the center seat section is positioned at a fixed
predetermined small angle relative to the footrest section. The
integral couch frame can pivot about a single horizontal axis
relative to a base frame. Such lounge chairs, known as "health
loungers", can often be found in baths, sanatoriums, etc. An
occupant can adjust such lounge chairs by shifting his or her
weight. The lounge chair can typically be adjusted between an
upright position, in which the front end of the integral couch
frame touches the floor, and a fully reclined position, in which
the footrest is aligned approximately horizontal.
[0007] An advantage of these "health loungers" is their simple
design, since the entire couch frame is connected with the base
frame by a single horizontal axle, around which the chair can
pivot. No further hinges between backrest and seat or between seat
and footrest are provided. Disadvantageous, however, is that
getting in and out of such couches is cumbersome, especially for
elderly persons. In order to sit down an occupant may enter from
the front, but that requires walking backward with legs spread far
apart to clear the footrest. Alternatively an occupant can attempt
to enter or exit the couch from the side, but that is difficult due
to armrests blocking access to the couch from the side.
[0008] Based on the previously described "health lounger" it is an
object of the current invention to provide an improved reclining
lounge chair, that can be adjusted between at least an upright
position and a reclined position, and that has ergonomic advantages
over known health loungers.
SUMMARY OF THE INVENTION
[0009] In one aspect of the invention, a reclining lounge chair is
provided, which comprises a footrest that is pivotally connected to
a center seat member by a footrest attachment axle. A footrest lift
mechanism is operatively connected to the footrest. The footrest
lift mechanism causes the footrest to rotate about the footrest
attachment axle as the lounge chair is reclined. While the lounge
chair is in its non-reclined, upright position, the footrest is
oriented approximately vertical. In this approximately vertical
orientation the footrest doesn't extend significantly forward of
the center seat member, thus allowing an occupant easy access to
the chair from the front. The center seat member may be at a height
from the floor that is typical for chairs, which allows an occupant
to easily get in and out of the lounge chair while in the upright
position. This ergonomic design is a significant improvement over
the previously described health lounges, which have fixed footrests
that extend forward of the center seat member at all times.
[0010] The reclining lounge chair may comprise a seat and backrest
subassembly, which is pivotally connected to a base frame by a seat
attachment axle. Also operatively connected to the base frame is
the rear end of the footrest lift mechanism. The front end of the
footrest lift mechanism is operatively connected to the footrest.
An occupant may adjust the lounge chair from the upright position
into a reclined position, simply by shifting his or her weight.
This causes the seat and backrest subassembly to rotate about the
seat attachment axle. Rotation of the seat and backrest subassembly
causes the footrest lift mechanism to simultaneously rotate the
footrest about the footrest attachment axle relative to the center
seat member. When the lounge chair reaches its fully reclined
position the footrest may have rotated from its original
approximately vertical orientation into an approximately horizontal
orientation, thus providing a comfortable sleeping position.
[0011] To exit, the lounge chair may be adjusted back into the
upright position. During the adjustment the footrest lift mechanism
causes the footrest to rotate from its approximately horizontal
orientation back into its approximately vertical orientation,
pointing downward from the footrest attachment axle towards the
floor. The vertical orientation of the footrest while the chair is
in its upright position allows an occupant to easily exit, as the
footrest does not obstruct the exit path.
[0012] Generally, recliners are known, which through a weight shift
or by adjusting the backrest, allow a footrest to rotate into an
elevated position. Such recliners, however, comprise comparatively
complex adjustment mechanisms, often including scissor style rods.
In contrast, the disclosed design is relatively simple, and
requires only a single footrest lift mechanism. Due to its simple
design the described lounge chair may be used outdoors, for
examples in backyards or baths, or commercially, e.g. in hospitals,
indoor public swimming pools, etc.
[0013] In another aspect of the invention, the footrest lift
mechanism may comprise two footrest lift bars, one on each side of
the lounge chair. Each footrest lift bar may be pivotally connected
at its front end to the footrest by a front footrest lift axle, and
at its rear end to the base frame by a rear footrest lift axle. The
footrest lift bars may be aligned almost congruent with the center
seat member. To achieve this, the rear footrest lift axle may be
located close to the seat attachment axle, preferably below and/or
in front of the seat attachment axle. Similarly, the front footrest
lift axle may be located close to the footrest attachment axle, and
preferably in front of the footrest attachment axle. The footrest
may comprise an embedded extension shape to provide sufficient
attachment space for both the footrest lift axle and the footrest
attachment axle.
[0014] In a further aspect of the invention, the front footrest
lift axle and the rear footrest lift axle may be located such, that
a line drawn from the front to the rear footrest lift axle
intersects a line drawn from the footrest attachment axle to the
seat attachment axle.
[0015] In yet another aspect of the invention a latch mechanism may
be provided to prevent the reclining chair from changing its
position too easily, especially to prevent movement of the chair
caused by unintended weight shifts of larger occupants. The latch
mechanism may lock the chair in one or more predetermined reclining
positions.
[0016] The latch mechanism may comprise a sliding arm, which rotate
relative to a latch disk, as the chair is reclined. The sliding arm
may be spring-loaded, compressing a latch spring upon axial
movement away from the latch disk. The sliding arm may comprise one
or more protrusions, that engage one or more radially extending
recesses in the latch disk as the chair reaches predetermined
reclining positions. Vice versa, the sliding arm may comprise
recesses that engage protrusions on the latch disk.
[0017] While the chair is in its upright position one or more
protrusions at the sliding arm resiliently engage one or more
recesses at the latch disk. When the chair is reclined the sliding
arm rotates about an axle extending through the center of the latch
disk. This forces the one or more protrusions of the sliding arm to
leave the corresponding recesses at the latch disk. The sliding arm
is pushed axially along its pivot axis in the center of the latch
disk away from the latch disk, thereby compressing the latch
spring. Upon reaching a second predetermined reclining position the
protrusions at the sliding arm resiliently reengage a second set of
recesses in the latch disk, causing the chair to assume a stable,
predetermined reclining position. An adjustment force larger than
the latch force is required to change the chair's position after it
has reached one of its predetermined positions.
[0018] The latch disk may comprise a plurality of recesses to
define a plurality of predetermined stable reclining positions.
Similarly, the sliding arm may comprise a plurality of protrusions
to define a plurality of predetermined stable reclining positions.
Protrusions and recesses may be substituted for each other, i.e.
the recesses may be located at the sliding arm and protrusions may
be located at the latch disk.
[0019] The sliding arm and the latch disk of the latch mechanism
may comprise a number of identical protrusions and/or recesses to
cause the same latch force in each position. They may also comprise
differently shaped protrusions and/or recesses to cause different
latch forces for different reclining positions. Using different
latch forces for different reclining positions can be used to
compensate an undesirable effect: Without a latch mechanism the
force required to adjust the chair out of its fully reclined
position would be higher than the force required to adjust the
chair out of an intermediate reclining position. Similarly, the
force required to adjust the chair out of its upright position may
be higher than the force required to adjust the chair out of an
intermediate position. In an intermediate position the chair may be
exactly balanced between rotating forward and backward, thus
requiring almost no adjustment force. The required adjustment force
is ultimately a function of where the occupant's center of gravity
is located relative to the seat attachment axle. To require similar
or equal adjustment forces in all three positions, the recesses of
the latch disk associated with the upright position may have a
shallow front exit, causing a relatively low latch force to exit
the upright position. In the intermediate position the recesses may
have a steeper angle to increase the latch force that must be
overcome to adjust the chair out of the intermediate position.
[0020] The following detailed description of the invention is
merely exemplary in nature and is not intended to limit the
invention or the application and uses of the invention.
Furthermore, there is no intention to be bound by any theory
presented in the preceding background of the invention or the
following detailed description of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] The invention is further explained with reference to the
following drawings.
[0022] FIG. 1a illustrates a known "health lounger" in an upright
position.
[0023] FIG. 1b illustrates the "health lounger" of FIG. 1a in a
reclined position.
[0024] FIG. 2 is a side view of an exemplary reclining lounge chair
in the upright position.
[0025] FIG. 3 is a side view of the reclining lounge chair as in
FIG. 2, shown in a fully reclined position.
[0026] FIG. 4 is a side view of the reclining lounge chair as in
FIGS. 2 and 3, shown in a folded state.
[0027] FIG. 5 is a schematic view of the reclining lounge chair as
in FIG. 2.
[0028] FIG. 6 is a schematic view of the reclining lounge chair as
in FIG. 3.
[0029] FIG. 7 is a schematic view overlaying the schematic views of
FIG. 5, FIG. 6, and a third intermediate reclining position.
[0030] FIGS. 8a and 8b are a side view and a top view of an
exemplary latch mechanism showing the mechanism engaged in a first
engaged state.
[0031] FIGS. 9a and 9b are showing the latch mechanism of FIGS. 8a
and 8b in an intermediate position between a first and a second
engaged state.
[0032] FIGS. 10a and 10b are showing the latch mechanism of FIGS.
8a and 8b after reaching a second engaged state.
[0033] FIG. 11 is a side view showing an alternative embodiment of
a latch mechanism.
[0034] FIG. 12 is a larger, more detailed view of FIG. 11.
DETAILED DESCRIPTION
[0035] FIGS. 1a and 1b show a traditional couch, that has become
known as a so called "health lounger". It comprises an integral
seat assembly 1, consisting of a backrest section 3, a center seat
section 5 and a footrest section 7. The seat assembly 1 is a rigid
unit, typically comprising an outer frame, in which a textile,
slightly elastic and/or cushioned support is held.
[0036] The entire seat assembly 1 may pivot about seat attachment
axle 9 relative to base frame 11. Base frame 11 typically comprises
a left and a right base frame element 11' which are laterally
spaced apart, and in between which seat assembly 1 is located. Seat
assembly 1 is connected to and held by base frame 11 only through
seat attachment axle 9.
[0037] Base frame 11 typically comprises four feet 13, two on each
side of seat assembly 1. Feet 13 are in contact with the floor 19,
and are spaced appropriately far apart to provide sufficient
stability.
[0038] Through a weight shift seat assembly 1 can be rotated as
illustrated by arrow 15 in FIG. 1a from an upright position
illustrated in FIG. 1a clockwise into a reclined position
illustrated in FIG. 1b. Seat assembly 1 thereby rotates about seat
attachment axle 9. In the reclined position footrest 7 assumes an
approximately horizontal orientation. Through a weight shift in the
opposite direction, as illustrated by arrow 17 in FIG. 1b, the
chair can rotate back from the reclined position into the upright
position, i.e. until the front end of footrest 7 touches the floor
19.
[0039] To facilitate the weight shift an armrest 6 is provided,
which is connected to or forms a part of base frame 11.
[0040] Getting onto and out off such "health loungers" is
difficult, because footrest 7 is always in a forward position in
front of center seat 5. An improved design is proposed, and
discussed with reference to FIG. 2 ff, whereby the same reference
numbers have been used when referring to comparable parts.
[0041] Referring now to FIG. 2, an exemplary embodiment of an
improved reclining lounge chair is illustrated. A seat assembly 1
is provided, comprising a backrest 3, a center seat member 5, and a
footrest 7. Center seat member 5 and backrest 3 may form a
subassembly, and assume a fixed, predetermined orientation to each
other. The subassembly of center seat 5 and backrest 3 may be a
single, rigid part.
[0042] Seat assembly 1 is pivotally connected to base frame 11,
i.e. both the left and the right base frame members 11', by a
horizontal seat attachment axle 9. Seat attachment axle 9 may be a
single shaft extending from the left frame member 11' to the right
frame member 11'. Seat attachment axle 9 may also consist of two
independent attachment members, one each attached to left and right
frame member 11'. Seat attachment axle 9 may be any connection
known in the art to pivotally attach center seat member 5 to base
frame 11.
[0043] Footrest 7 is connected to center seat member 5 by a
horizontal footrest attachment axle 23, which footrest 7 may pivot
about. Footrest attachment axle 23 may be a single shaft extending
across the width of the footrest. Footrest attachment axle 23 may
also comprise two independent attachment members, one on each side
of footrest 7. Rotation of footrest 7 about footrest attachment
axle 23 is controlled by footrest lift mechanism 25. Footrest lift
mechanism 25 typically consists of a pair of footrest lift bars
25', one on each side of the chair. The front end of each footrest
lift bar 25' is pivotally connected to footrest 7 with a front
footrest lift axle 29. The rear end of each footrest lift bar 25'
is pivotally connected to the base frame 11 by a rear footrest lift
axle 27.
[0044] Referring now to FIGS. 5 and 6, a footrest lift function
line 31 is shown, which is a straight line extending from the front
footrest lift axle 29 to the rear footrest lift axle 27. Also shown
is a seat member function line 33, which is a straight line
extending from footrest attachment axle 23 to seat attachment axle
9. As illustrated, the footrest lift axles 29 and 27 are positioned
such that the footrest lift function line 31 and the seat member
function line 33 intersect.
[0045] Referring back to FIG. 3, a rotation line or -plane 35 is
illustrated, which intersects both footrest attachment axle 23 and
front footrest lift axle 29. Footrest 7 can pivot around footrest
attachment axle 23 relative to seat member 5. Footrest lift axle 29
pivotally connects footrest lift mechanism 25 to footrest 7.
[0046] Due to the disclosed geometry, an occupant's weight shift
onto backrest 3, as illustrated by arrow 15 in FIG. 2, causes the
subassembly of center seat member 5 and backrest 3 to rotate
clockwise. The relative position between center seat member 5 and
backrest 3 remains unchanged, since both are in a fixed relative
alignment, and may form a single part. An occupant may hold onto
armrest 6 to facilitate the weight shift. Armrest 6 may be
connected to or form part base frame 11.
[0047] Clockwise rotation of seat assembly 1 around seat attachment
axle 9 causes footrest lift mechanism 25 to pivot about rear
footrest lift axle 27. Seat attachment axle 9 and rear footrest
lift axle 27 are operatively connected to base frame 11 at
different, fixed locations. Thus, center seat 5 and lift mechanism
25 have different pivot axes: Center seat 5 pivots about seat
attachment axle 9, while footrest lift mechanism 25 pivots about
rear footrest lift axle 27. This causes footrest attachment axle 23
to move relative to front footrest lift axle 29, as the chair is
reclined. As illustrated in FIG. 2 in the chair's upright position
front footrest lift axle 29 is in front of (i.e. appearing left of
in the drawing) footrest attachment axle 23. In the chair's fully
reclined position illustrated in FIG. 3, however, front footrest
lift axle 29 is behind (i.e. appearing right of in the drawing)
footrest attachment axle 23.
[0048] Rotation line 35, which indicates the relative position of
footrest attachment axle 23 to front footrest lift axle 29, rotates
at least 60.degree., preferably at least 80.degree., and especially
90.degree., when the lounge chair is adjusted from its upright
position to its fully reclined position. The illustrated rotation
of line 35 causes footrest 7 to rotate correspondingly. In the
chair's upright position, as shown in FIG. 2, footrest 7 assumes an
approximately vertical orientation towards the floor 19. In the
reclined position, as shown in FIG. 3, footrest 7 assumes an
approximately horizontal orientation. In the illustrated embodiment
footrest 7 rotates about 90.degree. between the chair's upright
position and the chair's fully reclined position. This provides a
comfortable reclined position, while also allowing an occupant to
easily enter and exit the chair in the upright position.
[0049] One aspect of achieving the desired kinematics is
illustrated in FIG. 3. As shown, rear footrest lift axle 27 is
located below seat attachment axle 9, i.e. below horizontal line
37, which intersects seat attachment axle 9. Alternatively, or in
addition thereto, footrest lift axle 27 may be located in front of
seat attachment axle 9, i.e. on the left side of vertical line 27,
which intersects seat attachment axle 9. Front footrest lift axle
29 may also be located above horizontal line 37.
[0050] Footrest lift mechanism 25 has an effective length that is
determined by the distance between front footrest lift axle 29 and
rear footrest lift axle 27. Correspondingly, center seat member 5
has an effective length that is determined by the distance between
footrest attachment axle 23 and seat attachment axle 9. The
effective length of footrest lift mechanism 25 may be 5%, and
preferably more than 10%, shorter than the effective length of the
center seat member 5.
[0051] Finally, favorable kinematics can also be achieved, if the
distance between the seat attachment axle 9 and the rear footrest
lift axle 29 is short relative to the height of seat attachment
axle 9 over floor 19. The distance between seat attachment axle 9
and rear footrest lift axle 29 is preferably less than 25%,
specifically less than 15%, less than 10%, less than 8% or even
less than 6% of the height of seat attachment axle 9 over floor 19.
On the other hand, the distance between seat attachment axle 9 and
rear footrest lift axle 29 should not be selected too short.
Favorably the distance between seat attachment axle 9 and rear
footrest lift axle 29 may be more than 2%, more than 4%, 6%, 8% or
10% of the height of seat attachment axle 9 over floor 19. The same
preferred distance ranges apply to the distance between front
footrest lift axle 29 and footrest attachment axle 23.
[0052] The disclosed embodiment is esthetically pleasing, as both
footrest lift bars 25' of footrest lift mechanism 25 may be
"hidden" behind an outer frame of center seat element 5. This can
be achieved by disposing footrest lift bars 25' immediately on the
inside of the outer frame of center seat member 5.
[0053] FIG. 7 schematically illustrates the reclining mechanism, by
superimposing a schematic view of the seat assembly 1 in the
upright position, an intermediate reclined position, and the fully
reclined position. The upright position is schematically also
illustrated in FIG. 5, the fully reclined position schematically
illustrated in FIG. 6.
[0054] Referring back to FIG. 2, a horizontal stop bar 65 is shown,
which extends between the left and the right base frame members 11'
of base frame 11. Horizontal stop bar 65 provides a stop for
backrest 3, thus limiting the movement of backrest 3, and defining
the maximum reclined position. Stop bar 65 is located at the base
frame 11 such, that in the thereby defined fully reclined position
footrest 7 is oriented approximately horizontal.
[0055] In an alternative embodiment, backrest 3 may pivot relative
to center seat member 5 by utilizing a separate mechanism, which is
hinted in FIGS. 2 and 3 by showing a backrest attachment axle 41.
In this embodiment a backrest locking mechanism must also be
provided. It is possible to provide a backward stop element, which
limits the maximum opening angle of backrest 3 against center seat
member 5, but allows backrest 3 to tilt forward against center seat
member 5 to accommodate a favorable storage position.
[0056] Referring to FIG. 4 it is shown, that the lounge chair may
assume a storage position, e.g. to minimize the space required to
store the lounge chair in extended periods without use, e.g. fall
and winter. To achieve this, backrest 3 may rotate around backrest
attachment axle 41 forward and towards center seat member 5. The
chair can be folded further by removing rear footrest lift axle 27
from base frame 11. For this purpose rear footrest lift axle 27 may
be attached to base frame 11 with screws, which can be removed with
the help of a tool, e.g. a wrench or screwdriver, so that rear
footrest lift axle 27 can be disconnected from base frame 11. This
allows further folding of the chair, until footrest 7 is parallel
to seat member 5. Base frame 11 may be designed such, that its
front feet 13 can pivot around a front foot attachment axle 101,
which is located close to armrest 6 at each base frame member 11'.
This allows front feet 13 to swivel backward, further reducing the
chair's storage size. In its storage position the chair may be
reduced to a height of about 30 cm and a length of about 120
cm.
[0057] Even though the lounge chair can be operated as described,
it may be further improved by providing a latch mechanism 51. This
is to prevent the chair from accidentally reclining, e.g. by an
unintentional weight shift of a larger occupant. Latch mechanism 51
may be located between any two parts of the chair that rotate
relative to each other while reclining. A suitable location for
locating latch mechanism 51 is around seat attachment axle 9, where
center seat member 5 rotates relative to base frame 11. Another
suitable location is around rear footrest lift axle 27, where
footrest lift mechanism 25 rotates relative to base frame 11.
[0058] Latch mechanism 51 may be a friction mechanism, which
increases the amount of torque required to rotate two parts against
each other, e.g. footrest lift mechanism 25 against base frame 11.
Latch mechanism 51 may also be a step mechanism, providing
incremental torque when exiting predetermined recline
positions.
[0059] An exemplary latch mechanism 51 is disclosed with reference
to FIG. 8a through 12. The disclosed latch mechanism comprises a
latch disk 53, which may have the shape of a complete disk, or a
partial disk. Latch disk 53 may be mounted torsionally rigid to the
inside of base frame 11, e.g. around rear footrest lift axle 27.
Footrest lift axle 27 will then pass through a hole located in the
center of latch disk 53. Latch disk 53 comprises radially aligned
and circumferentially spaced recesses 59 and protrusions 57.
Protrusions 57 may be bars, noses, ribs, or any suitable convex
feature. Recesses 59 may be notches, slots, grooves, indentations
or any other suitable concave feature. Recesses 59 transition into
protrusions 57 in form of slanted slopes 61.
[0060] Footrest lift bar 25' of footrest lift mechanism 25 may
comprise at least one protrusion 65 that is suitable to engage
recesses 59 of latch disk 53. Alternatively, footrest lift bar 25'
may comprise at least one recess that is suitable to engage
protrusions 57 of latch disk 53. Footrest lift bar 25' may extend
beyond footrest lift bar axle 27, and comprise two protrusions 65,
one on each side of footrest lift bar axle 27, and each engaging
latch disk 53 at opposite ends.
[0061] Referring to FIG. 11, footrest lift bar 25' may move axially
along footrest lift axle 27. Footrest lift bar 25', which forms a
sliding arm relative to latch disk 53, may be pushed towards latch
disk 53 by a force acting in direction of arrow 68. This force may
stem from pretensioned latch spring 67. Latch spring 67 may be
supported by rearward support plate 69. Rearward support plate 69
may be held by a bushing 70 that surrounds footrest lift bar axle
27 (not shown).
[0062] To recline the lounge chair, an occupant may shift his or
her weight, causing the entire seat assembly 1 to rotate about seat
attachment axle 9. As previously described, this causes footrest
lift bar 25' to rotate about rear footrest lift bar axle 27. During
this rotation protrusion 65 of footrest lift bar 25' has to exit
the corresponding recess 59 of latch disk 53. Latch disk 53 is
connected torsionally rigid to base frame 11. Protrusion 65 exits
recess 59 along tilted slope 61. FIG. 8a illustrates protrusion 65
resiliently engaging recess 59. FIG. 9a shows an intermediate
position, in which footrest lift bar 25' has rotated against latch
disk 53, and protrusion 65 has exited recess 59. Lift bar
protrusion 65 is now in contact with an opposite protrusion 57 on
latch disk 53. The transition from a protrusion-recess alignment to
a protrusion-protrusion alignment forces footrest lift bar 25' to
move axially along rear footrest lift bar axle 27 opposite the
pretension of latch spring 67 and opposite the arrow 68 shown in
FIG. 9a. During further rotation, as shown in FIG. 10a, lift bar
protrusion 65, supported by latch spring 67, engages the next latch
disk recess 59, thereby causing the chair to assume a relatively
stable, resilient, latched position.
[0063] The amount of incremental torque provided by latch mechanism
51 when rotating footrest lift bar 25' against base frame 11
depends on several factors, among them the force of spring 67, the
size and height of protrusion 65, the height of protrusions 57 and
recesses 59, and the angle of slope 61. Referring to FIGS. 8a
through 10a it is illustrated, that all protrusions and recesses,
as well as their height and their slopes 61 may be dimensioned
equal. However, the inherent torque required to rotate footrest
lift bar 25' against base frame 11 (i.e. without latch mechanism
51) may vary for different chair positions. To equalize the
adjustment force required to recline the chair from each locked
position to the next if may therefore be desirable to create an
inverted torque profile for latch mechanism 51. Latch mechanism 51
can be designed such, that the latch torque is small for reclining
positions that naturally require high adjustment forces, and vice
versa latch torque is high for reclining positions that naturally
require low adjustment forces.
[0064] As illustrated in FIGS. 11 and 12, the slope angles .alpha.,
.beta., or .chi. relating to the slopes 61 may be selected
differently, as may width 57a of the protrusions 57, so that
different "exit angles" cause different incremental torque when
entering or leaving various seating or reclined positions. Exiting
a particular latched position may require different amount of
torque, depending on which position is to be exited.
[0065] Finally, other latching or adjustment mechanisms are
possible, e.g. in the kind of a locking brake, e.g. to secure the
chair in an intermediate position, such that unintentional
adjustment is no longer possible.
[0066] While the present invention has been described with
reference to exemplary embodiments, it will be readily apparent to
those skilled in the art that the invention is not limited to the
disclosed or illustrated embodiments but, on the contrary, is
intended to cover numerous other modifications, substitutions,
variations and broad equivalent arrangements that are included
within the spirit and scope of the following claims.
* * * * *