U.S. patent application number 11/555463 was filed with the patent office on 2007-03-15 for back construction for seating unit.
Invention is credited to Douglas C. Ball, Alain Deslauriers, Leon Goldick, Jeff G. Sokalski.
Application Number | 20070057549 11/555463 |
Document ID | / |
Family ID | 22487449 |
Filed Date | 2007-03-15 |
United States Patent
Application |
20070057549 |
Kind Code |
A1 |
Ball; Douglas C. ; et
al. |
March 15, 2007 |
BACK CONSTRUCTION FOR SEATING UNIT
Abstract
A chair includes a base having a control assembly operably
supporting a seat assembly and also a back assembly for movement
about a seat tilt axis and a back tilt axis, respectively. The back
assembly includes a flexible sheet supported at upper/outer corners
by a back support structure and hanging downwardly. The flexible
sheet includes a lower portion coupled to the back support
structure by a tensioner for holding the lower portion rearwardly.
A vertically-adjustable lumbar mechanism is adjustably supported on
the back support structure and operably engages the flexible sheet
for flexing a lumbar area of the flexible sheet forwardly to
provide an optimal ergonomic horizontal and vertical convex shape
for postural lumbar support.
Inventors: |
Ball; Douglas C.;
(Senneville, CA) ; Goldick; Leon; (Beaconsville,
CA) ; Deslauriers; Alain; (Ile Laval, CA) ;
Sokalski; Jeff G.; (Montreal, CA) |
Correspondence
Address: |
PRICE HENEVELD COOPER DEWITT & LITTON, LLP
695 KENMOOR, S.E.
P O BOX 2567
GRAND RAPIDS
MI
49501
US
|
Family ID: |
22487449 |
Appl. No.: |
11/555463 |
Filed: |
November 1, 2006 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
11004300 |
Dec 3, 2004 |
|
|
|
11555463 |
Nov 1, 2006 |
|
|
|
10659662 |
Sep 10, 2003 |
6913315 |
|
|
11004300 |
Dec 3, 2004 |
|
|
|
10270228 |
Oct 10, 2002 |
6698833 |
|
|
10659662 |
Sep 10, 2003 |
|
|
|
09579166 |
May 25, 2000 |
6523898 |
|
|
10270228 |
Oct 10, 2002 |
|
|
|
60139599 |
Jun 17, 1999 |
|
|
|
Current U.S.
Class: |
297/284.4 |
Current CPC
Class: |
A47C 1/03 20130101; A47C
1/0305 20180801; A47C 1/03255 20130101; A47C 1/03274 20180801; A47C
7/462 20130101; A47C 1/023 20130101; A47C 7/004 20130101; A47C
1/03277 20130101; A47C 1/03272 20130101 |
Class at
Publication: |
297/284.4 |
International
Class: |
A47C 7/46 20060101
A47C007/46 |
Claims
1. A seating unit comprising: a base including a control; a
backrest assembly pivotally attached to the control for movement
between upright and reclined positions, the backrest assembly
including a support component with an upper connecting member; and
a seat operably supported on the control for synchronous movement
during movement of the backrest assembly between the upright and
reclined positions; the backrest assembly further including a back
shell having an upper region, a lumbar region disposed below the
upper region, and a lower region disposed below the lumbar region,
the back shell being attached at a location above the lumbar region
to the upper connecting member, the back shell further having an
array of elongated openings through the back shell, some of the
openings being positioned in the upper region and some of the
openings being positioned in at least one of the other regions, a
length of the openings in the upper region on average being shorter
than an average length of the openings in the other region.
2. The seating unit defined in claim 1, wherein the lumbar and
lower regions both include openings.
3. The seating unit defined in claim 2, wherein the openings in the
upper, lumbar and lower regions each define a different
pattern.
4. The seating unit defined in claim 2, wherein the openings in the
lower region are longer on average than the openings in the lumbar
region.
5. The seating unit defined in claim 1, wherein the back shell
includes a flexible deformable flat sheet that includes the upper,
lumbar, and lower regions,
6. The seating unit defined in claim 1, wherein at least some of
the openings in the upper and other regions include slots.
7. The seating unit defined in claim 1, wherein the support
component comprises a spine component.
8. A backrest comprising: a back shell with a surface configured
and adapted to support a seated person; the back shell having an
upper region, a lumbar region disposed below the upper region, and
a lower region disposed below the lumbar region; the back shell
including at least one upper connector located in the upper region
that is adapted to support the back shell, the back shell including
an array of first openings through the back shell in the upper
region and including an array of additional openings in at least
one of the other regions, with an average length of the first
openings being shorter than an average length of the additional
openings in the other region, at least the additional openings
being elongated and providing flexibility to the back shell in the
one region.
9. The backrest defined in claim 8, wherein the lumbar and lower
regions both include openings.
10. The backrest defined in claim 9, wherein the openings in the
upper, lumbar and lower regions each define a different
pattern.
11. The backrest defined in claim 9, wherein the openings in the
lower region are longer on average than the openings in the lumbar
region.
12. The backrest defined in claim 8, wherein the back shell
includes a flexible deformable flat sheet that includes the upper,
lumbar, and lower regions,
13. The backrest defined in claim 8, wherein at least some of the
openings in the upper and other regions include slots.
14. The backrest defined in claim 8, including a support component
connected to the at least one upper connector.
15. The backrest defined in claim 14, wherein the support component
includes a spine component extending vertically parallel a central
location on the back shell.
16. A back shell comprising: a polymeric component with a sheet
portion having a front surface configured and adapted to support a
seated person; the sheet portion having an upper region, a lumbar
region disposed below the upper region, and a lower region disposed
below the lumbar region; the sheet portion including an array of
first, second, and third openings through the sheet portion in the
upper, lumbar and lower regions, respectively, with an average
length of the first openings being shorter than an average length
of the second and being shorter than an average length of the third
openings, at least the second openings being elongated and
providing flexibility to the polymeric component in the lumbar
region.
17. The back shell defined in claim 16, wherein at least some of
the first, second, and third openings include slots.
18. The back shell defined in claim 17, wherein at least some of
the slots extend at an angle to vertical.
Description
RELATED APPLICATIONS
[0001] This application is a divisional of commonly assigned
co-invented application Ser. No. 11/004,300, entitled BACK
CONSTRUCTION FOR SEATING UNIT, filed Dec. 3, 2004, which is a
continuation of commonly assigned co-invented application Ser. No.
10/659,662, filed Sep. 10, 2003, entitled CHAIR CONSTRUCTION, now
U.S. Pat. No. 6,913,315, which is a continuation of commonly
assigned, co-invented application Ser. No. 10/270,228, filed Oct.
10, 2002, entitled CHAIR CONSTRUCTION, now U.S. Pat. No. 6,698,833,
which is a continuation of commonly assigned, co-invented
application Ser. No. 09/579,166, filed May 25, 2000, entitled CHAIR
CONSTRUCTION, now U.S. Pat. No. 6,523,898, which claims benefit
under 35 USC .sctn.119(e) of provisional application Ser. No.
60/139,599, filed Jun. 17, 1999, entitled ADJUSTABLE CHAIR
CONSTRUCTION.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to an adjustable chair
construction having an adjustable back and seat configured to
provide optimal postural support to a seated user during recline.
More particularly, the back includes a flexible back shell and a
lumbar mechanism for adjusting a shape of the flexible back shell
for improved lumbar support. The chair further includes a seat and
a reclineable back that move with a synchronous motion during
recline of the back.
[0003] There are many adjustable chairs in the art, including
chairs having adjustable backs. However, adjustability continues to
be a concern, since users have so many different body shapes and
preferences. Further, improvements are desired in the adjustment
mechanisms so that they are simpler and more intuitive to operate.
In particular, lumbar support and adjustability continue to be very
important to seated users. This is due, in part, to the fact that
people are spending considerable time in chairs, and also the
health of users' backs, and back pain can be affected. Thus, good
lumbar support and health continues to be of concern. It is noted
that the lumbar area on chairs is highly visible and easily
reachable, which further results in functional and aesthetic
attention being directed to the lumbar area and adjustment
mechanisms for the same.
[0004] In regard to synchronized seat and back movements,
synchronous chairs, such as Steelcase's Sensor chair, have gained
wide market acceptance for providing postural support during back
recline while also providing simultaneous seat and back rotation
that minimizes sheer or "shirt pull" in the lumbar area of a seated
user. However, further improvement is desired so that these
mechanisms provide even greater adjustability in terms of the
particular synchrotilt motion that they provide. For example, a
non-uniform synchronous motion is often desired, where the back and
seat move at a changing ratio during recline. From a manufacturing
standpoint, it is preferable that these new movements and back tilt
axis locations still use as many existing parts as possible, and
that they be as simple as possible. Also, many consumers are
looking for a new modernistic appearance.
[0005] Accordingly, a chair including an improved back
construction, armrest construction, and overall construction is
desired solving the aforementioned problems, but that provides the
adjustability, low cost, and ease of assembly needed in the
competitive chair industry.
SUMMARY OF THE INVENTION
[0006] In one aspect of the present invention, a seating unit
comprises a base including a control. A backrest assembly is
pivotally attached to the control for movement between upright and
reclined positions, the backrest assembly including a support
component with an upper connecting member. A seat is operably
supported on the control for synchronous movement during movement
of the backrest assembly between the upright and reclined
positions. The backrest assembly further includes a back shell
having an upper region, a lumbar region disposed below the upper
region, and a lower region disposed below the lumbar region, the
back shell being attached at a location above the lumbar region to
the upper connecting member, the back shell further having an array
of elongated openings through the back shell, some of the openings
being positioned in the upper region and some of the openings being
positioned in at least one of the other regions, a length of the
openings in the upper region on average being shorter than an
average length of the openings in the other region.
[0007] In another aspect of the present invention, a backrest
includes a back shell with a surface configured and adapted to
support a seated person. The back shell has an upper region, a
lumbar region disposed below the upper region, and a lower region
disposed below the lumbar region. The back shell includes at least
one upper connector located in the upper region that is adapted to
support the back shell. The back shell also includes an array of
first openings through the back shell in the upper region and an
array of additional openings in at least one of the other regions,
with an average length of the first openings being shorter than an
average length of the additional openings in the other region, at
least the additional openings being elongated and providing
flexibility to the back shell in the one region.
[0008] In yet another aspect of the present invention, a back shell
includes a polymeric component with a sheet portion having a front
surface configured and adapted to support a seated person. The
sheet portion has an upper region, a lumbar region disposed below
the upper region, and a lower region disposed below the lumbar
region. The sheet portion includes an array of first, second, and
third openings through the sheet portion in the upper, lumbar and
lower regions, respectively, with an average length of the first
openings being shorter than an average length of the second and
being shorter than an average length of the third openings, at
least the second openings being elongated and providing flexibility
to the polymeric component in the lumbar region.
[0009] These and other inventive aspects, objects, and advantages
will become apparent to one of ordinary skill in the art upon
review of the attached specification, claims, and appended
drawings.
DESCRIPTION OF DRAWINGS
[0010] FIG. 1 is a perspective view of a chair embodying the
present invention, the chair being in an upright position with its
back adjusted to a first upright position, and with the vertically
slidable lumbar adjustment mechanism adjusted to a lowered
position;
[0011] FIGS. 2-4 are front, top, and rear views of the chair shown
in FIG. 1;
[0012] FIG. 5 is a side view of the chair similar to FIG. 1, but
with the back and seat being shown in a reclined position;
[0013] FIG. 6 is a side view of the chair in the first upright
position similar to FIG. 1, but with hidden portions of the chair
being shown;
[0014] FIG. 7 is a side view similar to FIG. 6, but with the back
and seat adjusted to a second upright position that is located
above and forward of the first upright position in FIG. 6, and with
the vertically slidable lumbar mechanism being shown in a middle
location;
[0015] FIG. 7A is a fragmentary side view of the chair similar to
FIG. 6, but with the vertically slidable lumbar adjustment
mechanism adjusted to a raised position;
[0016] FIG. 8 is an exploded side view showing subassemblies of the
chair that are pivoted together;
[0017] FIGS. 9-11 are side, top, and front views of the control
housing shown in FIG. 1;
[0018] FIGS. 12-14 are side, top, and front views of the back tilt
bracket shown in FIG. 1;
[0019] FIGS. 15-17 are side, top, and front views of the
synchrotilt bracket position of the seat support shown in FIG.
1;
[0020] FIGS. 18-20 are side, top, and front views of the extension
for attachment to the back tilt bracket;
[0021] FIG. 21 is an exploded fragmentary perspective view of an
upper part of the center post of the base, the control including
the housing, the back tilt bracket and the energy spring, the
extension, and the back support shown in FIG. 1;
[0022] FIG. 21A is a cross-sectional side view of the control
showing a vertical height adjustment mechanism and side
actuator;
[0023] FIGS. 21B and 21C are fragmentary side and top views of
another side actuator for the vertical height adjustment
mechanism;
[0024] FIG. 22 is an exploded bottom perspective view of the seat
support;
[0025] FIGS. 23-25 are side, top, and front views of the seat
support bottom bracket shown in FIG. 22;
[0026] FIGS. 26-28 are bottom, front, and side views of the seat
support shown in FIG. 22;
[0027] FIG. 29 is an exploded fragmentary perspective view of the
back support/spine assembly and armrest assembly including the
armrest latching mechanism;
[0028] FIG. 30 is a fragmentary rear view of the components shown
in FIG. 29;
[0029] FIGS. 31 and 32 are fragmentary side and top views of the
components shown in FIG. 30;
[0030] FIGS. 33 and 34 are top views of the bushing and
stabilizer/follower, respectively, shown in FIG. 32;
[0031] FIGS. 35-37 are side, top, and front views of the armrest
assembly shown in FIG. 30;
[0032] FIG. 38 is a front view of the latch member shown in FIG.
29;
[0033] FIGS. 39 and 40 are fragmentary front views of the latch
member shown in FIG. 29, FIG. 39 illustrating a latched position,
FIG. 40 illustrating an unlatched position;
[0034] FIGS. 41-44 are side, enlarged side, rear, and top views of
the backrest frame shown in FIG. 1;
[0035] FIG. 45 is a front view of the backrest shell shown in FIG.
4;
[0036] FIGS. 46-49 are top, front, rear, and side views of the
vertically adjustable lumbar slide shown in FIG. 1;
[0037] FIGS. 50 and 51 are top cross-sectional views of the lumbar
side support arms and adjustment mechanism shown in FIG. 1, FIG. 50
showing the adjustment mechanism in a locked position and showing
the transverse drive train device, and FIG. 51 showing the
adjustment mechanism in an unlocked position permitting
adjustment;
[0038] FIG. 52 is a fragmentary front view of the lumbar side
support and adjustment mechanism shown in FIG. 50;
[0039] FIG. 52A is a cross-sectional view taken along line
LIIA-LIIA in FIG. 52;
[0040] FIGS. 53 and 54 are cross-sectional side views taken along
line LIII-LIII in FIG. 52, FIG. 53 showing the lumbar side support
arms adjusted to a forwardly bowed condition to provide a high
level of side/lateral lumbar support, and FIG. 54 showing the
lumbar side support arms adjusted to a relaxed, semi-planar
condition for providing minimal side/lateral lumbar support;
[0041] FIGS. 55-59 are perspective, front, side, top, and rear
views of a modified chair embodying the present invention;
[0042] FIGS. 60-62 are side, top, and rear views of the back and
back supporting structure shown in FIG. 55;
[0043] FIG. 63 is a side cross-sectional view of the armrest shown
in FIG. 55;
[0044] FIG. 64 is a cross-sectional view taken along the line
LXIV-LXIV in FIG. 63;
[0045] FIGS. 65 and 66 are top and side views of the armrest shown
in FIG. 55;
[0046] FIG. 67 is a perspective view of the latch member shown in
FIG. 65; and
[0047] FIG. 68 is a side view of the internal components of the
present armrest shown in FIG. 55, the tubular shroud and the inner
bearing tube being removed to expose the latching mechanism for
height adjustment.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENT
[0048] A chair 50 (FIG. 1) embodying the present invention includes
a base 51, a control 52 mounted on the base 51, and a seat 53 and a
back tilt bracket 54 pivoted to the control 52 for synchronous
movement during recline of a back construction 55. An extension 56
is adjustably supported on the back tilt bracket 54 to form a back
tilt bracket subassembly, and is pivotally connected to a back
support 57. The back support 57 is separately pivotally connected
to a backrest frame 58, and the backrest frame 58 is separately
pivoted to a seat support structure 82. The combination of the
extension 56 and back tilt bracket 54 (as one unit), the back
support structure 57, the backrest frame 58, and the seat support
structure 82 of the seat 53 are connected in a four-bar linkage
arrangement, as discussed below. Advantageously, the extension 56
is adjustable on the back tilt bracket 54 (see FIGS. 6 and 7) to
change the angular position of the back 55 when in the rest or
upright position, and further provides a secondary back tilt axis
93 that is located rearward of a rear edge of the seat 53. This
provides a unique back movement upon recline that is more compliant
with a seated user's body movements during recline than many
reclineable chairs, as discussed below. The back support 57
includes a spine assembly 60 that is pivoted to a rear end of the
extension 56 and that extends upwardly.
[0049] An armrest assembly 61 is operably supported on the spine
assembly 60 for vertical adjustment by means of an armrest mount 62
on the spine assembly 60. A handle 63 on one of the armrests 64 is
operably connected to a latch 65 on the armrest mount 62 via a
tension cable for easy adjustment of the armrests 64. The
arrangement of the backrest frame 58, the spine assembly 60, the
back tilt bracket 54, and the seat 53 provides a unique synchronous
movement that, among other things, pivots the armrests 64 at an
angular rate between a rate of the seat 53 and the back 55 during
recline of the back 55. The back 55 includes a flexible back shell
66 having a lumbar section, a lumbar slide 68 slidably engaging a
rear surface of the back shell 66 and operably supported
thereagainst for changing a vertical shape of the lumbar section,
and lumbar side arms 69 engaging a rear surface of the back shell
66 and also operably supported thereagainst for changing a
horizontal shape of the sides/lateral area of the lumbar section
67.
[0050] More specifically, the base 51 (FIG. 1) includes a
floor-engaging bottom including a center hub 70 with radially
extending legs 71 having castors 72 on their ends. A vertically
adjustable center post 73 includes an extendable gas strut that
extends from hub 70 and engages a housing 74 on control 52.
[0051] The control 52 is described below in sufficient detail for
an understanding of the present invention. Nonetheless, it is noted
that the control 52 is described in more detail in U.S. Pat. No.
5,630,647, issued May 20, 1997, entitled Tension Adjustment
Mechanism for Chairs, which patent is incorporated herein by
reference in its entirety. Notably, even though the present
invention is described in combination with the control 52, the
scope of the present invention is believed to include other chair
controls and chair or back constructions. For example, the present
invention is believed to be usable on chair controls that provide a
synchrotilt motion to a seat and a back, and to be usable on other
chairs having reclineable backs, other chairs having flexible backs
providing postural support to a seated user, and other chairs
having vertically adjustable armrests.
[0052] The control 52 includes the housing 74 (FIGS. 9-11), which
is pan-shaped and that includes a recess receiving an energy
mechanism 75 (FIG. 21). A height adjustment mechanism 74' (FIG.
21A) is operably supported on housing 74 to operably engage a gas
spring on base 51 for chair height adjustment. The back tilt
bracket 54 (FIGS. 12-14) includes side flanges 76 pivoted to sides
of the housing 74 at back tilt axis 59 by a tubular pin or bushing
and a rearwardly extending tail section 77. Seat assembly 53
includes a synchrotilt bracket 80 (FIGS. 15-17) that pivotally
engages the housing 74 at seat tilt axis 81. Synchrotilt bracket 80
has a nose 80' with a bushing 80'' therein that slidably engages a
front lip 81' on the housing 74. Seat assembly 53 (FIGS. 26-28)
further includes a seat support structure or bracket 82 (FIGS.
23-25) for securely supporting a semi-rigid flexible seat shell 84
on the synchrotilt bracket 80. The seat support bracket 82 is
pivoted to the synchrotilt bracket 80 at axis 82A for manual
angular adjustment of the seat 53, and a latch mechanism 82'' holds
the seat 53 in a selected angular position on the synchrotilt
bracket 80. The bracket 82 (FIG. 8) is pivoted to the synchrotilt
bracket 80 at axis 82' and provides for manual adjustment of the
seat 53 while the back 55 is in the upright position, including
adjustment of the seat angle or of the seat depth. A seat cushion
and fabric 83 (FIG. 1) are attached to the seat shell 84 (FIG. 22)
to form a comfortable chair seat. Side supports 85 (FIG. 22) are
fixed or welded to the seat support structure 82 at mounts 83' and
extend upwardly on opposing sides of the seat support structure 82,
and side flanges 83'' stiffen the support structure 82. The side
supports 85 are tubular and include upper end sections positioned
at about a seated user's hip joint, and define an axis of rotation
85A (FIG. 1) aligned approximately with the seated user's hip
joint, as described below. Notably, the back tilt axis 59 and the
manual seat angle axis 82' may or may not generally align with one
another. A seat depth adjustment mechanism 84' can also be provided
on the seat 53. Seat shell 84 includes ribs 85' as needed.
[0053] The extension 56 (FIGS. 18-20) includes an H-shaped body
having a transverse wall section 86, opposing forward arms 87, and
opposing rearward arms 88. The forward arms 87 are spaced apart and
include holes 89 configured to be pivoted to the sides of housing
74 at back tilt axis 59. Stabilizing tabs 90 extend from arms 88 at
a location between the forward arms 87 and the transverse wall
section 86. Stabilizing tabs 90 slidingly engage the sides of back
tilt bracket 54 and help stabilize the vertical movement of the
extension 56 on the back tilt bracket 54. Rearward arms 88 extend
rearwardly from transverse wall section 86 and include apertures 92
defining a second back tilt axis 93. (Notably, additional apertures
can be provided on rearward arms 88 for defining different
locations for axis 93, if desired.) An E-shaped notched flange 94
is attached to the transverse wall section 86. The E-shaped flange
94 defines three notches 95 for selective engagement by a
spring-biased movable tooth 96 (FIGS. 12 and 13) on the tail
section 77 of the back tilt bracket 54. The movable tooth 96 can be
actuated in different ways, such as manually by an operator
grasping the tooth 96 or by a Bowden cable and lever actuator for
remote actuation. The extension 56 (FIG. 21) is manually adjustably
pivotable about the back tilt axis 59 by releasing tooth 96 from
notched flange 94, by adjusting the extension 56 angularly relative
to the back tilt bracket 54, and by engaging the tooth 96 into a
newly selected notch 95. As described below, adjustment of the
extension 56 raises (or lowers) the back support structure 57 (see
FIGS. 6 and 7) and in turn raises (or lowers) the back 55, so that
they are positioned to provide angularly different postural support
when in the upright position.
[0054] Spine assembly 60 (FIG. 29) includes a vertical frame member
97 having a C-shaped cross section with stiffening ribs 98 formed
integrally therein or attached to its concave side. Opposing
C-shaped side bearings 99 are positioned along edges of the concave
side, and a rack 100 having teeth 101 is also positioned on one
side. A stabilizer 99' (FIGS. 32 and 34) extends from plate-like
mount 62 into ribs 98 as noted below. The vertical frame member 97
defines a bottom pivot 102 for pivotal connection to holes 92 on
extension 56 (FIG. 8) at second back tilt axis 93, and further
defines a top pivot 103 for pivotally engaging the backrest frame
58 at axis 103', as described below.
[0055] Armrest assembly 61 (FIG. 29) includes the armrest mount 62
with side edges configured to slidably engage the side bearings 99
for vertical movement. Mount 62 slidably engages frame member 97 to
help stabilize the mount 62 on the spine assembly 60. A tubular
armrest frame 104 is attached to mount 62 and includes side
sections 105 that extend in a curvilinear fashion from the mount 62
around to a side of the chair 50. Armrests 64 (FIG. 30) including
forearm support pads 64' are supported on ends of the side sections
105. The latch 65 (FIGS. 38-40) is slidably attached to mount 62
(FIG. 29) and includes a body 106 that slides on mount 62. The
latch 65 further includes latching teeth 107 shaped to securely
selectively engage the teeth 101 on rack 100, and spring feet 108
bias the latching teeth 107 into engagement with the teeth 101 on
rack 100 (see FIGS. 38-40). The right (or left) side section 105
(FIG. 35) includes a down flange 109' that extends downwardly below
one of the armrests 64, and a finger-actuateable lever 109 of
handle 63 is pivoted to the down flange 109' at a pivot axis 109''.
A telescoping Bowden cable 110 is operably connected between an end
of the lever 109 and the latch 65. By squeezing and thus pivoting
the lever 109, the cable 110 that extends through side section 105
is tensioned and the latch 65 is biased to a release position (FIG.
40) as the spring feet 108 compress. When the lever 109 is
released, the spring feet 108 bias the cable 110 to a normally
released position (FIG. 39). Notably, the handle 63 provides a
distinctive appearance resembling a bicycle brake handle and is
actuateable much like a bicycle brake handle. It is contemplated
that the present adjustable armrest can also be actuated by
different means, and further that the present actuator can be used
with various adjustable armrests, such as armrests that are
adjustable laterally, longitudinally (i.e., fore-to-aft),
vertically, rotationally, and/or in other ways known in the
art.
[0056] As described below, the back support 57 including the spine
assembly 60 (FIG. 8) forms part of a four-bar linkage that operably
supports the back 55 and seat 53 for synchronous movement during
recline of the back 53, the back support 57 and spine assembly 60
being one of the links that extends between the back 55 and the
seat 53. In the four-bar linkage arrangement, during recline of
back 55, the spine assembly 60 rotates at an intermediate rate
between the angular rate of rotation of the seat 53 and back 55.
Due to the attachment of the armrest assembly 61 to spine assembly
60, the armrest assembly 61 also moves at the intermediate rate of
rotation, the ratio of the angular movement of the back, the
armrest, and the seat being about 2:1.5:1. The actual angular
movements "A," "B," and "C" of the seat, armrest, and back during
recline are about 12.degree., 17.degree., and 22.degree.,
respectively, in the illustrated chair 50 (FIG. 5). Notably, by
changing a height of the armrest assembly 61, the angular rate of
rotation does not change, although the rearward movement and path
of translation of the armrest assembly 61 changes due to a longer
(or shorter) distance of the armrest assembly 61 from second back
tilt axis 93. By changing angular position of the extension 56 by
means of E-flange 94 and tooth 96, or by selecting a different hole
location for axis 93 in the extension 56, the location of the
second back tilt axis 93 can be changed to provide still another
different movement of the back 55 and movement of the armrest
assembly 61.
[0057] The backrest frame 58 (FIGS. 41-44) includes a tubular frame
member 111 (FIGS. 1 and 43), and further includes a rod extension
assembly 112. The rod extension assembly 112 includes a knuckle 113
fixed to a center of the tubular frame member 111, a pair of rods
114 that extend upwardly from knuckle 113, and a top bracket 115
that engages a top of the rods 114. The tubular frame member 111
(FIG. 1) includes opposing ends that wrap around to sides of the
chair 50 and that are pivoted to top end sections of the side
supports 85 on seat 53 at hip axis 85A (FIG. 1). The tubular frame
member 111 is located inboard of the side supports 105 of the
armrest frame 104, so that the backrest frame 58 does not interfere
with the armrest frame 104 despite the range of positions that each
may be located in during recline of the back 55. The knuckle 113
(FIG. 42) includes a pivot recess 117 that pivotally engages the
upper end of the spine assembly 60 at top pivot 103 to define a
third axis of rotation. The top bracket 115 (FIG. 43) includes a
center section 118 with bosses 119 for receiving the upper ends of
the rods 114, and further includes side wings 120 that extend
laterally to side edges of the back 55. The top bracket 115
includes reinforcement ribs as needed for stiffness, and includes a
radiused front surface 122 for receivingly attaching a top of the
back shell 123 (FIGS. 45 and 3) described below. The top bracket
115 is further arcuately shaped for aesthetics and functional
support to a seated user. The rods 114 are shaped to act as
vertical guides to the vertically adjustable lumbar slide 68, as
described below. The backrest frame 58 is semi-rigid but
torsionally flexible enough to provide some twisting flexure when a
seated user reclines the back 55 and twists/rotates his/her upper
body.
[0058] The back construction 55 includes a flexible back shell 123
(FIG. 45) that comprises a flexible flat sheet, such as a sheet
made of polypropylene or similar engineering type polymer. Where
the sheet is translucent or transparent, the back construction 55
has a novel appearance, and further, it provides a functional
result in that the adjusted position of the back construction 55
can be easily seen. The flat sheet includes a center section filled
with a pattern of short vertical slots 124 forming a V-shaped
arrangement with lower slots 124 being longer than upper slots 124,
and includes side sections filled with a pattern of short
horizontal slots 125 generally covering the remainder of the sheet,
the lower slots 125 also being longer than the upper slots 125. The
slots 124 and 125 are arranged to provide a desired level of
postural support and twisting/torsional flexibility. An upper edge
126 of the flexible back shell 123 wraps onto a front surface of
the top bracket 115 (FIG. 3) and is fixed to the top bracket 115. A
horizontal central/lumbar area 127 (FIG. 6) of the flexible back
shell 123 is supported by the lumbar slide 68 on the rods 114, as
described below. A lower edge 128 (FIG. 6) of the flexible back
shell 123 is anchored to the lower area on the spine assembly 60 at
location 129 by an elastic tensioner 130. The tensioner 130 can be
made of any number of different stretchable or
extendable/retractable materials or structures, such as a sheet of
rubber elastomer, neoprene, spring steel, or the like. The
tensioner 130 can be covered with fabric or colored as desired for
aesthetics.
[0059] The lumbar slide 68 (FIGS. 46-49) includes a rigid body 132
positioned on and slidably engaging a rear surface of the back
shell 123 (FIG. 6) and a top mount 133. The top mount 133 includes
tubular sleeves 133' that are slidably engaged with the rods 114
for vertical adjustment between a top position (FIG. 7A), a bottom
position (FIG. 6), and anywhere therebetween. Ribs 133'' further
stiffen the rigid body 132. It is contemplated that depressions can
be located on the interfacing surfaces between the lumbar slide 68
and back shell 123 for forming a detent thereon, but at present it
is contemplated that the frictional engagement between the two
interfacing surfaces and between the lumbar slide 68 and the rods
114 is sufficient to hold the lumbar slide 68 in a selected
vertically adjusted position. The rigid body 132 is sufficiently
rigid and the back shell 123 is sufficiently flexible so that by
engaging the rigid body 132 at different heights on the rear
surface of the back shell 123, the back shell 123 changes shape in
its lumbar area. This change in shape is assisted by the tensioner
130 which tensions the back shell 123 as the tensioner 130 pulls
the lower edge 128 of the back shell 123 downwardly and rearwardly,
causing the back shell 123 to be draped downwardly and against a
front surface of the rigid body 132 of the lumbar slide 68. The top
mount 133 is movable between the top bracket 115 and the knuckle
113 in a manner that limits the vertical adjustability of the
lumbar slide 68. The lumbar slide 68 is adjusted manually by
grasping handle 155 or mount 133 or other part of the lumbar slide
68 and then pulling upwardly or downwardly. There is enough
friction on the lumbar slide 68 to hold it in a selected
position.
[0060] The fact that the slide 68 is moving on a near vertical
plane as shown in FIG. 7A in combination with back 66 and the
tensioner 130 results in an automatic change of seat depth of as
much as 2 inches when the lumbar slide 68 is vertically adjusted.
Specifically, one of the strong features of the design is the depth
increase to the seat when the slide 68 is raised, and decrease when
the slide 68 is lowered. Normally, tall people want the slide 68
elevated, and short people want it lowered. Hence, seat depth is
automatically accomplished in this new arrangement.
[0061] The lumbar adjustable side arms 69 (FIG. 47) include a pair
of opposing T-shaped sheet members 135 cut from a semi-rigid,
resiliently flexible material such as nylon, stiff polymer, stiff
metal, or the like. The sheet members 135 are attached to a front
surface of the rigid body 132 on opposite sides. In particular, the
sheet members 135 include a body section 136, with legs 137-139
extending from body section 136. The first leg 137 extends inwardly
about two-thirds of the way toward a vertical centerline 140 of the
rigid body 132 and is attached at location 141. The second leg 138
extends upwardly along a mid-perimeter section 142 of rigid body
132 and is attached at location 143. The third leg 139 extends
downwardly along a lower corner perimeter section 144 of the rigid
body 132 and extends a short distance around the lower corner. A
strap 146 is attached to rigid body 132 at lower corner 144 and
defines a slit-like open area thereunder, which defines a guide for
leg 139 between the rigid body 132 and the strap 146. The third leg
139 extends slidably under the strap 144 through the open area.
When third leg 139 is pulled toward second leg 138, the body
section 136 bulges forwardly in direction "F" (see FIG. 53),
causing the adjacent area on back shell 123 to flex forwardly. By
adjusting the bulge of body section 136, the lateral side support
provided to a seated user in the kidney area/side lumbar area is
varied. In other words, by pulling third leg 139 toward second leg
138, the body section 136 causes an edge section of the back shell
123 to wrap partially around a seated user's lumbar area, thus
providing side and lateral support to the seated user. This is
accomplished completely from a rear of the back shell 123, without
intruding onto a front side of the back shell 123.
[0062] The "bulging" or forward movement of body section 136 at its
side lumbar area is controlled by a lumbar adjustment mechanism 148
(FIGS. 50-52). The lumbar adjustment mechanism 148 (FIG. 50)
includes a horizontal rotatable drive train formed by right rod
149, center link 150, and left rod 151. The rods 149 and 151 are
connected to center link 150 by hex-shaped socket and hex-shaped
ball universal connections 152 and 153. The drive train extends
transversely across the lumbar slide 68, and is operably supported
in a groove or recess 154 formed on the back of lumbar slide 68 by
a ribbed housing 154'. The ribbed housing 154' includes ribs 133'
that rotatably support the rods 149 and 151 of the drive train. A
handle 155 is non-rotatably attached to one end of rod 149, but is
slidably supported on the rod 149 for axial movement. A pair of
friction clutch wheels 156 and 157 with intermeshing teeth are
positioned on rod 149, with one wheel 156 being attached to handle
155 for axial movement on rod 149 and the other wheel 157 being
non-rotatably attached to rod 149. A spring 157' biases the wheels
156 and 157 into engagement with each other when handle 155 is
released. A strap 158 of spring steel or the like extends from rod
149 (FIG. 47) downwardly to the third leg 139, and a second strap
158 extends from rod 151 downwardly to its respective third leg
139. When handle 155 is axially moved to disengage the wheel 156
from the wheel 157 and is then rotated, rods 149 and 151 are also
rotated, causing the straps 158 to wrap around the rods 149 and 151
(compare FIGS. 53 and 54). As the effective length of the straps
158 and 159 are shortened due to their length being wound around
the rods 149 and 151, the third legs 139 are drawn or pulled upward
so that the body section 136 bulges forwardly (FIG. 53). When the
handle 155 is released, the clutch wheels 156 and 157 engage,
holding the lumbar slide 68 in a fixed forwardly bulged position.
The bulged third legs 139 push the lateral side section of the back
shell 66 forwardly, partially around a seated user, as indicated by
arrows 139A in FIG. 3. By repeating the above but by rotating the
handle 155 in an opposite direction, the straps 158 are relaxed,
allowing the stiffness of the third leg 139 to cause the third leg
139 to move to its natural planar shape. This allows the lateral
side section of the back shell 66 to flex toward a more planar
condition.
[0063] Notably, the forward movement of body section 136 is
influenced by making the straps 158 stiffer or more flexible. The
straps 158 must be stiff enough to press the body section 136
forwardly as the straps 158 are unwound from the rods 149 and 151,
and preferably are stiff enough to urge the leg 139 toward the
planar condition. The stiffness of the straps 158 and 159
influences the shape of the back shell 66 and the amount of lateral
support so that it also gives support to a seated user's sides in
the lumbar or lower back area. Specifically, the stiff straps 158
and 159 provide a leaf-spring-like section that extends from the
rods 149 and 151 forwardly to bias the back shell 66 forwardly when
the straps 158 and 159 are only partially wound around the rods 149
and 151.
[0064] The vertical height adjustment mechanism 74' (FIG. 21A) is
operably mounted to the control housing 74 as follows. An inverted
U-channel 179 is welded to housing 74 and includes a top horizontal
wall 179'. A tapered tube section 183 is positioned in holes in the
U-channel 179 and in housing 74 and is secured in place by flared
flanges and/or by welding at its top and bottom ends. The top of
the adjustable center post 73 is positioned in tube section 183,
with a release button 180 for releasing the extendable gas spring
in the center post 73 positioned in an accessible top/end location.
A bridge 181 is positioned on U-channel 179 with its center section
182 extending generally over the release button 180. A side-to-side
guide slot 182' is formed in center section 182, and a follower 184
is slidingly engaged with the slot 182'. The follower 184 includes
a bottom curvilinear surface 185 forming a ramp that is constructed
to operably engage and actuate the release button 180 as the
follower 184 is moved toward one side. A spring 186 attached
between the follower 184 and the bridge 181 biases the follower 184
to a normal position where the release button 180 is not depressed.
A cable 187 is connected to follower 184 at attachment tab 188. A
sleeve 189 telescopingly supports the cable 187, and the cable 187
is positioned through a side of the housing 74 to an actuator lever
positioned either on a side of the housing 74 or in another
convenient location. The cable assembly formed by cable 187 and
sleeve 189 are commonly called Bowden cables.
[0065] A modified vertical height adjustment mechanism 74A' (FIGS.
21B and 21C) includes a bridge 181A attached to a bottom wall of
housing 74 by a hooked end 190 and a bolted end 191. A lever 192 is
pivoted to the bridge 181A at first end 193 and includes a second
end 194 that abuttingly engages the release button 180. A roller
195 is operably rollingly positioned under the bridge 181A and on
the lever 192. A spring 186A biases the roller 195 in a first
direction, and a cable 187A is connected to the roller 195 for
pulling the roller 195 in a second direction for operating the
lever 192. The center post 73 and cable sleeve 189 are connected to
the housing 74 in a manner similar to the adjustment mechanism 74'.
Due to the downwardly concave shape of bridge 181A and the upwardly
concave shape of the lever 192, the roller 195 biases the lever 192
into the release button 180 to depress the release button 180 as
the roller 195 is pulled by the cable 187A, but the release button
180 is released as the cable is released and the spring 186A pulls
the roller 195 back to a normal rest position.
[0066] The chair 50 offers several advantages over the known art.
The extension 56 provides a back tilt axis that is located rearward
of a rear edge of the seat, thus providing a different back
movement during back recline that has a significantly different
feel and, to many consumers, an improved feel. The extension allows
existing synchrotilt controls to be used with only a limited number
of additional major parts. Further, the extension is angularly
adjustable on the existing control, thus allowing the angle of the
back and seat to be changed when in the upright position. The
armrest assembly is pivoted to a spine assembly that moves at a
rate of rotation that is between the angular rate of rotation of
the back and seat, such that the armrest assembly 61 also moves at
an intermediate rate of rotation. Thus, the present back, armrest,
and seat move at synchronous rates of rotation that are about
2:1.5:1 at the start of recline. The ratio of these synchronous
rates of rotation will vary depending upon the extension and other
members in the mechanisms and links that provide the synchronous
motion. Nonetheless, the angular and intermediate rate of rotation
of the armrest is advantageous, since the armrests are better
positioned for the seated user regardless of whether the back is in
a partial or full recline position. Also, it is noted that the
armrests are vertically adjustable while seated in the chair by
simply grasping the release lever under one of the armrests, thus
making adjustment relatively easy.
[0067] The chair 50 also has a back construction that provides
significant advantages. The back shell is very flexible, so that it
provides a postural support that is very comfortable. A vertically
adjustable lumbar slide supports the back shell in a lumbar area of
a seated user. The lumbar slide is vertically adjustable to provide
different amounts of lumbar support, depending upon a seated user's
preference. Advantageously, the lumbar slide physically changes the
shape of the lumbar area on the back shell, so that the lumbar
support is immediate and active, rather than only reactive to
pressure from a seated user's lumbar. A lower edge of the back
shell is anchored by a tensioner that pulls the back shell against
the lumbar slide. This allows the lumbar slide to control the shape
of the lumbar area of the back shell, even though the lumbar slide
only engages a rear surface of the back shell. A novel lateral
lumbar side support is provided that adjustably wraps partially
around a seated user for comfortable side support. The lumbar side
support is adjustable via a single rotatable actuator, transversely
positioned on the lumbar slide.
[0068] A chair 50B (FIGS. 55-59) is similar to the chair 50, but
includes modifications to its back, and its armrest and armrest
supporting structure. In chair 50B, components and features that
are similar or identical to the components and features of chair 50
are identified with the same numbers but with the addition of the
letter "B". This is done for convenience and to reduce redundant
discussion and unnecessary paperwork, and should not be construed
to be for other non-essential reasons.
[0069] The chair 50B (FIG. 55) includes a base 51B, a control 52B,
a seat 53B, a back tilt bracket 54B (FIG. 57), a back construction
55B, an extension 56B, a back support 57B, and a backrest frame
58B. The back support 57B includes a modified spine assembly 60B
(sometimes called a "back frame" herein) and a modified armrest
assembly 61B, described as follows.
[0070] The modified spine assembly 60B (FIGS. 60 and 62) includes a
T-shaped member 200B securely and non-adjustably fixed to a knuckle
113B. The T-shaped member 200B includes a top bracket 115B, and a
vertical section 114B. The top bracket 115B ergonomically supports
a top of the back shell 66B, for twisting movement of a seated user
and the lumbar slide 68B is located between the knuckle 113B and
the back shell 66B. The lumbar slide 68B slidably engages the
vertical section 114B for ergonomic support of a seated user. Two
tubular frame members 111B extend outwardly downwardly and
forwardly from knuckle 113B, and each includes an end that is
pivotally attached to the associated side supports 85B at the pivot
axis 85B'. The knuckle 113B is pivoted to a top of the vertical
frame member 97B of spine assembly 60B at top pivot 103B. The
bottom of the vertical frame member 97B is pivoted at bottom pivot
92B to a rear of the extension 56B.
[0071] It is noted that the back tilt axis 59B, the seat tilt axis
81B, the secondary tilt axis 93B, the top pivot axis 103B', and the
side pivot axis 85B' of chair 50B are in the same relative
locations as the axes 59, 81, 93, 103', and 85A of chair 50.
[0072] The back construction 55B is basically the same as the back
construction 55, except that back construction 55B does not include
a cushion on its front surface. It is contemplated that a permanent
or removable cushion can be applied to the seat and back. It is
contemplated that clear or translucent material (such as a
polyolefin, polycarbonate, or hybrid blended for durability,
flexibility, and transparency) will be used to make the back shell
66B. This provides a novel appearance, and also provides a
functional result in that the lumbar slide 68B can be seen from a
position in front of the chair, thus making it easier to see where
the lumbar slide 68B is located or if an adjustment is required
before getting in the chair.
[0073] The modified armrest assembly 61B (FIG. 63) is supported on
an armrest support structure comprising an L-shaped strut 202B
(FIG. 56) with a horizontal leg 203B and a vertical leg 204B. It is
contemplated that the horizontal leg 203B can be an extension of
the horizontal portion of side supports 85B. In such case, the
strut 202B moves with the seat 53B during recline. Alternatively,
the strut 202B can be fixed to the housing 74B, such that the
armrest assembly 61B is stationary and does not move upon
recline.
[0074] The vertical leg 204B (sometimes called the "inner tube"
herein) is structural and obround with flat sides and rounded ends
(FIG. 64). The illustrated armrest 64B (FIG. 63) is T-shaped (or
sometimes it is referred to as an inverted L-shape), and includes a
vertical portion 206B that slidably engages the vertical leg 204B,
and further includes a horizontal portion 207B. The vertical
portion 206B includes an outer tube 208B (FIG. 64) and an
intermediate plastic sleeve 209B that telescopingly and adjustably
engage the vertical leg 204B. A shroud 215B surrounds the vertical
leg 204B to provide a clean aesthetic appearance to the support
structure. An L-shaped latch 210B (FIG. 63) is pivoted to the
vertical portion 206B at pivot 205B. A vertical leg 211B of the
latch 210B is located within the inner tube 204B, and includes a
tooth 212B (FIG. 68) that releasably engages a multi-notched catch
213B that is fixed within the inner tube 204B. A horizontal leg
214B of the L-shaped latch 210B extends forwardly, and extends
through an aperture in the outer shroud 215B to form a
finger-shaped handle 215B' under a top part of the armrest in front
of the vertical leg 204B. A leaf spring 216B biases the latch 210B
so that the tooth 212B naturally engages a selected notch in the
catch 213B. By pressing on the handle portion of the horizontal leg
214B, the latch 210B is pivoted in a forward direction to disengage
the tooth 212B.
[0075] The horizontal portion 207B of the armrest 64B (FIG. 63)
includes a mounting block or plate 218B securely fixed atop the
vertical tube 208B. A top armrest subassembly 219B includes a
cushion-supporting plate 220B pivoted to the mounting block 218B at
main pivot 221B. A front of the mounting block 218B includes one or
more protrusions 222B. A latch lever 223B is pivoted to the plate
220B at a latch pivot (FIG. 66) by a pivot pin 225B. The latch
lever 223B includes a front section 224B forming a handle under a
front of the armrest 64B, and further includes a rear section 225B
having recesses 226B shaped to selectively engage the protrusion(s)
222B. A foam cushion 227B (FIG. 63) is supported on the plate 220B
and extends onto a front of 227B' of the armrest 64B, with the
handle-forming front section 224B positioned just below it in an
easily accessible location. A spring 228B biases the latch lever
223B to a position where the interlock recesses 226B engages one of
the protrusion(s) 222B. An alignment pin 229B on plate 220B extends
into a hole 230B in the latch lever 223B to help maintain alignment
of the latch lever 223B on the plate 220B.
[0076] The armrest 64B can be vertically adjusted by depressing the
handle-forming portion of horizontal member 214B of latch 210B,
moving the armrest vertically to a newly selected position, and
then releasing the handle-forming portion. The armrest 64B can be
angularly adjusted by depressing the handle-forming portion of
latch lever 223B, angularly adjusting the armrest subassembly
227B/220B, and releasing the latch lever 223B.
[0077] While the preferred embodiment has been described in some
detail, those skilled in the art will recognize that various
alternatives may be used that embody the invention described by the
following claims. Accordingly, these claims are not intended to be
interpreted as being unnecessarily limiting.
* * * * *