Note: Descriptions are shown in the official language in which they were submitted.
CA 02881887 2015-02-12
WO 2014/047255 PCT/US2013/060560
CHAIR ARM ASSEMBLY
BACKGROUND OF THE INVENTION
[0001] The present invention relates to a chair assembly, and in
particular to an office
chair arm assembly vertically and horizontally adjustable, and including an
arm cap
assembly that is pivotably and linearly adjustable.
BRIEF SUMMARY OF THE INVENTION
[0002] One aspect of the present invention is to provide a chair assembly
that comprises
a 4-bar linkage assembly comprising a first linkage member having a first end
and a
second end, a second linkage member having a first end and a second end, a
third linkage
member having a first end pivotably coupled to the first end of the first
linkage member
for rotation about a first pivot point, and a second end pivotably coupled to
the first end
of the second linkage member for rotation about a second pivot point, and a
fourth
linkage member having a first end pivotably coupled to the second end of the
first linkage
member for rotation about a third pivot point, and second end pivotably
coupled to the
second end of the second linkage member for rotation about a fourth pivot
point,
wherein the 4-bar linkage assembly includes a lower end and an upper end that
is
adjustable between a raised position, and a lowered position. The chair
assembly further
comprises an arm rest assembly adapted to support the arm of a seated user
thereon
and supported on an upper end of the 4-bar linkage assembly, wherein the lower
end of
the 4-bar linkage assembly is pivotably supported by an arm support structure
for
pivotable movement of about a fifth pivot point, such that the upper end of
the 4-bar
linkage assembly is movable between a first position and a second position
located
laterally outward from the first position.
[0003] Another aspect of the present invention is to provide a chair
assembly comprising
a 4-bar linkage assembly comprising a first linkage member having a first end,
a second
end, and a U-shaped cross-sectional configuration located along the length
thereof, a
second linkage member having a first end, a second end, and a U-shaped cross-
sectional
configuration located along the length thereof, and wherein the first linkage
member and
the second linkage member cooperate to form an interior space extending
longitudinally
along the lengths of the first and second linkage members, a third linkage
member having
1
CA 02881887 2015-02-12
WO 2014/047255 PCT/US2013/060560
a first end pivotably coupled to the first end of the first linkage member for
rotation
about the first pivot point, and a second end pivotably coupled to the first
end of the
second linkage member for rotation about a second pivot point, and a fourth
linkage
member having a first end pivotably coupled to the second end of the first
linkage
member for rotation about a third pivot point, and a second end pivotably
coupled to the
second end of the second linkage member for rotation about a fourth pivot
point,
wherein the 4-bar linkage assembly includes a lower end and an upper end that
is
vertically adjustable between a raised position, and a lowered position. The
chair
assembly further comprises an arm rest assembly adapted to support the arm of
the
seated user thereon and supported on an upper end of the 4-bar linkage
assembly, and
the locking assembly including a first locking link having a first surface and
a second
locking link having a plurality of teeth corresponding to a plurality of
vertical positions of
the 4-bar linkage located between the raised position and the lowered
position, wherein
the first and second locking links are movable with respect to one another
between a
locked position, wherein the first surface engages at least one of the
plurality of teeth to
prevent adjustment of the 4-bar linkage between the raised and lowered
positions, and
an unlocked position, wherein the first surface is spaced from the plurality
of teeth,
thereby allowing the 4-bar linkage to be adjusted between the raised and
lowered
positions, and wherein at least a substantial portion of both the first and
second locking
links are located within the interior space.
[0004] Yet another aspect of the present invention is to provide a chair
assembly that
comprises an arm support structure, an arm rest assembly adapted to
comfortably
support the arm of a seated user thereon, an arm support assembly having a
lower end
supported by the arm support structure, and an upper end supporting the arm
rest
assembly thereon, wherein the arm support assembly is adjustable between a
vertically
raised position and a vertically lowered position, and a locking assembly. The
locking
assembly comprises a first locking link having at least one of a first surface
and a plurality
of teeth, a second locking link having the other of the first surface and the
plurality of
teeth, movable between a locked position, wherein the first surface engages at
least one
of the plurality of teeth to prevent adjustment of the arm support assembly
between the
raised and lowered positions, and an unlocked position, wherein the first
surface is
spaced from the plurality of teeth, thereby allowing the arm support assembly
to be
2
CA 02881887 2015-02-12
WO 2014/047255 PCT/US2013/060560
adjusted between the raised and lowered positions, an actuator link operably
coupled
with the first locking link and adapted to move between a first position,
wherein the first
locking link is moved by the actuator link to the locked position, and a
second position,
wherein the first locking link is moved by the actuator link to the unlocked
position, and
an actuator member operably coupled with the actuator link, wherein at least a
portion
of the actuator member may be actuate by a seated user, thereby allowing the
user to
move the actuator link between the first and second positions.
[0005] Another aspect of the present invention is an arm rest assembly for
an office
chair. The arm rest assembly includes an outer member having a cushion mounted
thereto, and an inner member configured to be secured to an office chair
structure. The
inner member has teeth disposed thereon. The arm rest assembly also includes
upper
and lower members extending between and pivotably interconnecting the inner
and
outer members to form a 4-bar linkage. The arm rest assembly also includes a
vertical
adjustment lock assembly to lock the height of the cushion relative to the
inner member.
The vertical adjustment lock assembly includes a movable release member, and
an
actuator member that shifts between locked and unlocked positions upon
movement of
the release member. The actuator member defines a base end. The vertical
adjustment
lock assembly further includes a moveable locking member with teeth that
selectively
engage the teeth on the inner member of the 4-bar linkage. A spring biases the
actuator
member towards the locked position, and also biases the teeth of the pivotable
locking
member out of engagement with the teeth on the inner member of the 4-bar
linkage.
The base end of the actuator member moves into a first recess of the locking
member to
permit movement of the locking member teeth out of engagement with the teeth
of the
inner member of the 4-bar linkage. The arm rest assembly further includes a
second lock
having a locking second recess in the locking member that receives the end of
the
actuator member and prevents movement of the locking member when a downward
force is applied to the cushion.
[0006] Still yet another aspect of the present invention is to provide a
chair assembly
that comprises a seat support structure including a seat support surface
configured to
support a seated user thereon, an arm rest assembly including an arm support
surface to
support the arm of a seated user thereon, and an arm support assembly having
an upper
end supporting the arm support assembly in a greater vertical height than the
seat
3
CA 02881887 2015-02-12
WO 2014/047255 PCT/US2013/060560
support surface, and a lower end that includes a select one of a pivot boss
and a pivot
aperture. The chair assembly further comprises an arm support structure that
includes
the other of the pivot boss and the pivot aperture, wherein the pivot boss is
received
within the pivot aperture for pivotably supporting the arm support assembly
for rotation
about a pivot point between a first position and a second position, the pivot
boss having
a conical-shape, and wherein the aperture has a conical-shape closely
corresponding to
the shape of the pivot boss.
[0007] Another aspect of the present invention is to provide a chair
assembly that
comprises an arm support assembly having an upper end and a lower end, an arm
rest
assembly adapted to support the arm of a seated user thereon and supported on
the
upper end of the arm support assembly, and an arm support structure pivotably
supporting the arm support assembly for pivoting movement about a
substantially
vertical axis, such that the upper end of the arm support assembly is
pivotable about the
substantially vertical axis between a first position and a second position
located laterally
outward from the first position. The chair further comprises a seat support
structure
including a seat support surface configured to support a seated user thereon,
wherein
the seat support surface includes a longitudinal axis, and wherein the upper
end of the
arm support assembly moves greater than or equal to about 22 outwardly from
an axis
parallel with the longitudinal axis of the seat support surface, and wherein
the upper end
of the arm support assembly moves greater than or equal to about 17 inwardly
from the
axis parallel with the longitudinal axis of the seat support surface.
[0008] These and other features, advantages, and objects of the present
invention will
be further understood and appreciated by those skilled in the art by reference
to the
following specification, claims, and appended drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] Fig. 1 is a front perspective view of a chair assembly embodying
the present
invention;
[0010] Fig. 2 is a rear perspective view of the chair assembly;
[0011] Fig. 3 is a side elevationa I view of the chair assembly showing
the chair assembly
in a lowered position and in a raised position in dashed line, and a seat
assembly in a
retracted position and in an extended position in dashed line;
4
CA 02881887 2015-02-12
WO 2014/047255 PCT/US2013/060560
[0012] Fig. 4 is a side elevationa I view of the chair assembly showing
the chair assembly
in an upright position and in a reclined position in dashed line;
[0013] Fig. 5 is an exploded view of the seat assembly;
[0014] Fig. 6 is an enlarged perspective view of the chair assembly with
a portion of the
seat assembly removed to illustrate a spring support assembly;
[0015] Fig. 7 is a front perspective view of a back assembly;
[0016] Fig. 8 is a side elevationa I view of the back assembly;
[0017] Fig. 9A is an exploded front perspective view of the back
assembly;
[0018] Fig. 9B is an exploded rear perspective view of the back assembly;
[0019] Fig. 10 is an enlarged perspective view of an area X, Fig. 9A;
[0020] Fig. 11 is an enlarged perspective view of an area XI, Fig. 2;
[0021] Fig. 12 is a cross-sectional view of an upper back pivot assembly
taken along the
line XII-XII, Fig. 7;
[0022] Fig. 13A is an exploded rear perspective view of the upper back
pivot assembly;
[0023] Fig. 13B is an exploded front perspective view of the upper back
pivot assembly;
[0024] Fig. 14 is an enlarged perspective view of the area XIV, Fig. 9B;
[0025] Fig. 15A is an enlarged perspective view of a comfort member and a
lumbar
assembly;
[0026] Fig. 15B is a rear perspective view of the comfort member and the
lumbar
assembly;
[0027] Fig. 16A is a front perspective view of a pawl member;
[0028] Fig. 16B is a rear perspective view of the pawl member;
[0029] Fig. 17 is a partial cross-sectional perspective view along the
line XVIII-XVIII, Fig.
15b;
[0030] Fig. 18A is a perspective view of the back assembly, wherein a
portion of the
comfort member is cut away;
[0031] Fig. 18B is an exploded perspective view of a portion of the back
assembly;
[0032] Fig. 19 is a perspective view of a control input assembly
supporting a seat support
plate thereon;
[0033] Fig. 20 is a perspective view of the control input assembly with
certain elements
removed to show the interior thereof;
[0034] Fig. 21 is an exploded view of the control input assembly;
CA 02881887 2015-02-12
WO 2014/047255 PCT/US2013/060560
[0035] Fig. 22 is a side elevational view of the control input assembly;
[0036] Fig. 23A is a front perspective view of a back support structure;
[0037] Fig. 23B is an exploded perspective view of the back support
structure;
[0038] Fig. 24 is a side elevational view of the chair assembly
illustrating multiple pivot
points thereof;
[0039] Fig. 25 is a side perspective view of the control assembly showing
multiple pivot
points associated therewith;
[0040] Fig. 26 is a cross-sectional view of the chair showing the back in
an upright
position with the lumbar adjustment set at a neutral setting;
[0041] Fig. 27 is a cross-sectional view of the chair showing the back in
an upright
position with the lumbar portion adjusted to a flat configuration;
[0042] Fig. 28 is a cross-sectional view of the chair showing the back
reclined with the
lumbar adjusted to a neutral position;
[0043] Fig. 29 is a cross-sectional view of the chair in a reclined
position with the lumbar
adjusted to a flat configuration;
[0044] Fig. 29A is a cross-sectional view of the chair showing the back
reclined with the
lumbar portion of the shell set at a maximum curvature;
[0045] Fig. 30A is an exploded view of a moment arm shift assembly;
[0046] Fig. 30B is an exploded view of a moment arm shift drive assembly;
[0047] Fig. 31 is a cross-sectional perspective of the moment arm shift
assembly;
[0048] Fig. 32 is a top plan view of a plurality of control linkages;
[0049] Fig. 33A is a side perspective view of the control assembly with
the moment arm
shift in a low tension position and the chair assembly in an upright position;
[0050] Fig. 33B is a side perspective view of the control assembly with
the moment arm
shift in a low tension position and the chair assembly in a reclined position;
[0051] Fig. 34A is a side perspective view of the control assembly with
the moment arm
shift in a high tension position and the chair assembly in an upright
position;
[0052] Fig. 34B is a side perspective view of the control assembly with
the moment arm
shift in a high tension position and the chair assembly in a reclined
position;
[0053] Fig. 35 is a chart of torque vs. amount of recline for low and
high tension settings;
[0054] Fig. 36 is a perspective view of a direct drive assembly with the
seat support plate
exploded therefrom;
6
CA 02881887 2015-02-12
WO 2014/047255 PCT/US2013/060560
[0055] Fig. 37 is an exploded perspective view of the direct drive
assembly;
[0056] Fig. 38 is a perspective view of a vertical height control
assembly;
[0057] Fig. 39 is a side elevational view of the vertical height control
assembly;
[0058] Fig. 40 is a side elevational view of the vertical height control
assembly;
[0059] Fig. 41 is a cross-sectional front elevational view of a first
input control assembly;
[0060] Fig. 42A is an exploded view of a control input assembly;
[0061] Fig. 42B is an enlarged perspective view of a clutch member of a
first control input
assembly;
[0062] Fig. 42C is a exploded view of the control input assembly;
[0063] Fig. 43 is a side perspective view of a variable back control
assembly;
[0064] Fig. 44 is a perspective view of an arm assembly;
[0065] Fig. 45 is an exploded perspective view of the arm assembly;
[0066] Fig. 46 is a side elevational view of the arm assembly in an
elevated position and a
lowered position in dashed line;
[0067] Fig. 47 is a partial cross-sectional view of the arm assembly;
[0068] Fig. 48 is a top plan view of the chair assembly showing the arm
assembly in an in-
line position and in angled positions in dashed line;
[0069] Fig. 49 is an isometric view of an arm assembly including a
vertical height
adjustment lock;
[0070] Fig. 50 is an isometric view of an arm assembly including a
vertical height
adjustment lock;
[0071] Fig. 51 is an isometric view of an arm assembly including a
vertical height
adjustment lock;
[0072] Fig. 52 is a top plan view of the chair assembly showing an arm
rest assembly in
an in-line position and rotated positions in dashed line, and in a retracted
position and an
extended position in dashed line;
[0073] Fig. 53 is an exploded view of the arm rest assembly;
[0074] Fig. 54 is a cross-sectional view of the arm rest assembly;
[0075] Fig. 55 is a perspective view of the chair assembly;
[0076] Fig. 56 is a front elevational view of the chair assembly;
[0077] Fig. 57 is a first side elevational view of the chair assembly;
[0078] Fig. 58 is a second side elevational view of the chair assembly;
7
CA 02881887 2015-02-12
WO 2014/047255 PCT/US2013/060560
[0079] Fig. 59 is a rear elevational view of the chair assembly;
[0080] Fig. 60 is a top plan view of the chair assembly;
[0081] Fig. 61 is a bottom plan view of the chair assembly;
[0082] Fig. 62 is a perspective view of the arm assembly;
[0083] Fig. 63 is a front elevational view of the arm assembly;
[0084] Fig. 64 is a first side elevational view of the arm assembly;
[0085] Fig. 65 is a second side elevational view of the arm assembly;
[0086] Fig. 66 is a rear side elevational view of the arm assembly;
[0087] Fig. 67 is a top plan view of the arm assembly; and
[0088] Fig. 68 is a bottom plan view of the arm assembly.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0089] For purposes of description herein, the terms "upper," "lower,"
"right," "left,"
"rear," "front," "vertical," "horizontal," and derivatives thereof shall
relate to the
invention as oriented in Fig. 1. However, it is to be understood that the
invention may
assume various alternative orientations and step sequences, except where
expressly
specified to the contrary. It is also to be understood that the specific
devices and
processes illustrated in the attached drawings, and described in the following
specification are exemplary embodiments of the inventive concepts defined in
the
appended claims. Hence, specific dimensions and other physical characteristics
relating
to the embodiments disclosed herein are not to be considered as limiting,
unless the
claims expressly state otherwise. Various elements of the embodiments
disclosed herein
may be described as being operably coupled to one another, which includes
elements
either directly or indirectly coupled with one another. Further, the term
"chair" as
utilized herein encompasses various seating arrangements, including office
chairs, vehicle
seating, home seating, stadium seating, theater seating, and the like.
[0090] The reference numeral 10 (Figs. 1 and 2) generally designates a
chair assembly
embodying the present invention. In the illustrated example, the chair
assembly 10
includes a castered base assembly 12 abutting a supporting floor surface 13, a
control or
support assembly 14 supported by the castered base assembly 12, a seat
assembly 16
and back assembly 18 each operably coupled with the control assembly 14, and a
pair of
arm assemblies 20. The control assembly 14 (Fig. 3) is operably coupled to the
base
8
CA 02881887 2015-02-12
WO 2014/047255 PCT/US2013/060560
assembly 12 such that the seat assembly 16, the back assembly 18 and the arm
assemblies 20 may be vertically adjusted between a fully lowered position A
and a fully
raised position B, and pivoted about a vertical axis 21 in a direction 22. The
seat
assembly 16 is operably coupled to the control assembly 14 such that the seat
assembly
16 is longitudinally adjustable with respect to the control assembly 14
between a fully
retracted position C and a fully extended position D. The seat assembly 16
(Fig. 4) and
the back assembly 18 are operably coupled with the control assembly 14 and
with one
another such that the back assembly 18 is movable between a fully upright
position E and
a fully reclined position F, and further such that the seat assembly 16 is
movable between
a fully upright position G and a fully reclined position H corresponding to
the fully upright
position E and the fully reclined position F of the back assembly 18,
respectively.
[0091] The base assembly 12 includes a plurality of pedestal arms 24
radially extending
and spaced about a hollow central column 26 that receives a pneumatic cylinder
28
therein. Each pedestal arm 24 is supported above the floor surface 13 by an
associated
caster assembly 30. Although the base assembly 12 is illustrated as including
a multiple-
arm pedestal assembly, it is noted that other suitable supporting structures
maybe
utilized, including but not limited to fixed columns, multiple leg
arrangements, vehicle
seat support assemblies, and the like.
[0092] The seat assembly 16 (Fig. 5) includes a relatively rigid seat
support plate 32
having a forward edge 34, a rearward edge 36, and a pair of C-shaped guide
rails 38
defining the side edges of the seat support plate 32 and extending between the
forward
edge 34 and the rearward edge 36. The seat assembly 16 further includes a
flexibly
resilient outer seat shell 40 having a pair of upwardly turned side portions
42 and an
upwardly turned rear portion 44 that cooperate to form an upwardly disposed
generally
concave shape. In the illustrated example, the seat shell 40 is comprised of a
relatively
flexible material such as a thermoplastic elastomer (TPE). In assembly, the
outer seat
shell 40 is secured and sandwiched between the seat support plate 32 and a
plastic,
flexibly resilient seat pan 46 which is secured to the seat support plate 32
by a plurality of
mechanical fasteners. The seat pan 46 includes a forward edge 48, a rearward
edge 50,
side edges 52 extending between the forward edge 48 and the rearward edge 50,
a top
surface 54 and a bottom surface 56 that cooperate to form an upwardly disposed
generally concave shape. In the illustrated example, the seat pan 46 includes
a plurality
9
CA 02881887 2015-02-12
WO 2014/047255 PCT/US2013/060560
of longitudinally extending slots 58 extending forwardly from the rearward
edge 50. The
slots 58 cooperate to define a plurality of fingers 60 therebetween, each
finger 60 being
individually flexibly resilient. The seat pan 46 further includes a plurality
of laterally
oriented, elongated apertures 62 located proximate the forward edge 48. The
apertures
62 cooperate to increase the overall flexibility of the seat pan 46 in the
area thereof, and
specifically allow a forward portion 64 of the seat pan 46 to flex in a
vertical direction 66
with respect to a rearward portion 68 of the seat pan 46, as discussed further
below. The
seat assembly 16 further includes a foam cushion member 70 that rests upon the
top
surface 54 of the seat pan 46 and is cradled within the outer seat shell 40, a
fabric seat
cover 72 (Figs. 1 and 2), and an upper surface 76 of the cushion member 70. A
spring
support assembly 78 (Figs. 5 and 6) is secured to the seat assembly 16 and is
adapted to
flexibly support the forward portion 64 of the seat pan 46 for flexure in the
vertical
direction 66. In the illustrated example, the spring support assembly 78
includes a
support housing 80 comprising a foam and having side portions 82 defining an
upwardly
concave arcuate shape. The spring support assembly 78 further includes a
relatively rigid
attachment member 84 that extends laterally between the side portions 82 of
the
support housing 80 and is located between the support housing 80 and the
forward
portion 64 of the seat pan 46. A plurality of mechanical fasteners 86 secure
the support
housing 80 and the attachment member 84 to the forward portion 64 of the seat
pan 46.
The spring support assembly 78 further includes a pair of cantilever springs
88 each
having a distal end 90 received through a corresponding aperture 92 of the
attachment
member 84, and a proximate end 94 secured to the seat support plate 32 such
that the
distal end 90 of each cantilever spring 88 may flex in the vertical direction
66. A pair of
linear bearings 96 are fixedly attached to the attachment member 84 and
aligned with
the apertures 92 thereof, such that the linear bearing 96 slidably receives
the distal ends
90 of a corresponding cantilever spring 88. In operation, the cantilever
springs 88
cooperate to allow the forward portion 64 of the seat pan 46, and more
generally the
entire forward portion of seat assembly 16 to flex in the vertical direction
66 when a
seated user rotates forward on the seat assembly 16 and exerts a downward
force on the
forward edge thereof.
[0093] The back assembly 18 (Figs. 7-9B) includes a back frame assembly 98
and a back
support assembly 99 supported thereby. The back frame assembly 98 is generally
CA 02881887 2015-02-12
WO 2014/047255 PCT/US2013/060560
comprised of a substantially rigid material such as metal, and includes a
laterally
extending top frame portion 100, a laterally extending bottom frame portion
102, and a
pair of curved side frame portion 104 extending between the top frame portion
100 and
the bottom frame portion 102 and cooperating therewith to define an opening
106
having a relatively large upper dimension 108 and a relatively narrow lower
dimension
110.
[0094] The back assembly 18 further includes a flexibly resilient, plastic
back shell 112
having an upper portion 114, a lower portion 116, a pair of side edges 118
extending
between the upper portion 114 and a lower portion 116, a forwardly facing
surface 120
and a rearwardly facing surface 122, wherein the width of the upper portion
114 is
generally greater than the width of the lower portion 116, and the lower
portion 116 is
downwardly tapered to generally follow the rear elevational configuration of
the frame
assembly 98. A lower reinforcement member 115 attaches to hooks 117 (Fig. 9A)
of
lower portion 116 of back shell 112. Reinforcement member 115 includes a
plurality of
protrusions 113 that engage reinforcement ribs 134 to prevent side-to-side
movement of
lower reinforcement member 115 relative to back shell 112. As discussed below,
reinforcement member 115 pivotably interconnects back control link 342 (Fig.
26) to
lower portion 116 of back shell 112 at pivot points or axis 346.
[0095] The back shell 112 also includes a plurality of integrally molded,
forwardly and
upwardly extending hooks 124 (Fig. 10) spaced about the periphery of the upper
portion
114 thereof. An intermediate or lumbar portion 126 is located vertically
between the
upper portion 114 and the lower portion 116 of the back shell 112, and
includes a
plurality of laterally extending slots 128 that cooperate to form a plurality
of laterally
extending ribs 130 located therebetween. The slots 128 cooperate to provide
additional
flexure to the back shell 112 in the location thereof. Pairings of lateral
ribs 130 are
coupled by vertically extending ribs 132 integrally formed therewith and
located at an
approximate lateral midpoint thereof. The vertical ribs 132 function to tie
the lateral ribs
130 together and reduce vertical spreading therebetween as the back shell 112
is flexed
at the intermediate portion 126 thereof when the back assembly 18 is moved
from the
upright position E to the reclined position F, as described further below. The
back shell
112 further includes a plurality of laterally-spaced reinforcement ribs 134
extending
longitudinally along the vertical length of the back shell 112 between the
lower portion
11
CA 02881887 2015-02-12
WO 2014/047255 PCT/US2013/060560
116 and the intermediate portion 126. It is noted that the depth of each of
the ribs 134
increases the further along each of the ribs 134 from the intermediate portion
126, such
that the overall rigidity of the back shell 112 increases along the length of
the ribs from
the intermediate portion 126 toward the lower portion 116.
[0096] The back shell 112 further includes a pair of rearwardly extending,
integrally
molded pivot bosses 138 forming part an upper back pivot assembly 140. The
back pivot
assembly 140 (Figs. 11-13B) includes the pivot bosses 138 of the back shell
112, a pair of
shroud members 142 that encompass respective pivot bosses 138, a race member
144,
and a mechanical fastening assembly 146. Each pivot boss 138 includes a pair
of side
walls 148 and a rearwardly-facing concave seating surface 150 having a
vertically
elongated pivot slot 152 extending therethrough. Each shroud member 142 is
shaped so
as to closely house the corresponding pivot boss 138, and includes a plurality
of side
walls 154 corresponding to side walls 148, and a rearwardly-facing concave
bearing
surface 156 that includes a vertically elongated pivot slot 143 extending
therethrough,
and which is adapted to align with the slot 152 of a corresponding pivot boss
138. The
race member 144 includes a center portion 158 extending laterally along and
abutting
the top frame portion 100 of the back frame assembly 98, and a pair of a
rcuately-shaped
bearing surfaces 160 located at the ends thereof. Specifically, the center
portion 158
includes a first portion 162, and a second portion 164, wherein the first
portion 162 abuts
a front surface of the top frame portion 100 and second portion 164 abuts a
top surface
of the top frame portion 100. Each bearing surface 160 includes an aperture
166
extending therethrough and which aligns with a corresponding boss member 168
integral
with the back frame assembly 98.
[0097] In assembly, the shroud members 142 are positioned about the
corresponding
pivot bosses 138 of the back shell 112 and operably positioned between the
back shell
112 and race member 144 such that the bearing surface 156 is sandwiched
between the
seating surface 150 of a corresponding pivot boss 138 and a bearing surface
160. The
mechanical fastening assemblies 146 each include a bolt 172 that secures a
rounded
abutment surface 174 of the bearing washer 176 in sliding engagement with an
inner
surface 178 of the corresponding pivot boss 138, and threadably engages the
corresponding boss member 168 of the back shell 112. In operation, the upper
back
12
CA 02881887 2015-02-12
WO 2014/047255 PCT/US2013/060560
pivot assembly 140 allows the back support assembly 99 to pivot with respect
to the back
frame assembly in a direction 180 (Fig. 8) about a pivot axis 182 (Fig. 7).
[0098] The back support assembly 99 (Figs. 9A and 9B) further includes a
flexibly resilient
comfort member 184 (Figs. 15A and 15B) attached to the back shell 112 and
slidably
supporting a lumbar assembly 186. The comfort member 184 includes an upper
portion
188, a lower portion 190, a pair of side portions 192, a forward surface 193
and a
rearward surface 195, wherein the upper portion 188, the lower portion 190 and
the side
portions 192 cooperate to form an aperture 194 that receives the lumbar
assembly 186
therein. As best illustrated in Figs. 9B and 14, the comfort member 184
includes a
plurality of box-shaped couplers 196 spaced about the periphery of the upper
portion
188 and extending rearwardly from the rearward surface 195. Each box-shaped
coupler
196 includes a pair of side walls 198 and a top wall 200 that cooperate to
form an interior
space 202. A bar 204 extends between the side walls 198 and is spaced from the
rearward surface 195. In assembly, the comfort member 184 (Figs. 12-14) is
secured to
the back shell 112 by aligning and vertically inserting the hooks 124 of the
back shell 112
into the interior space 202 of each of the box-shaped couplers 196 until the
hooks 124
engage a corresponding bar 204. It is noted that the forward surface 120 of
the back
shell 112 and the rearward surface 195 of the comfort member 184 are free from
holes
or apertures proximate the hooks 124 and box-shaped couplers 196, thereby
providing a
smooth forward surface 193 and increasing the comfort to a seated user.
[0099] The comfort member 184 (Figs. 15A and 15B) includes an integrally
molded,
longitudinally extending sleeve 206 extending rearwardly from the rearward
surface 195
and having a rectangularly-shaped cross-sectional configuration. The lumbar
assembly
186 includes a forwardly laterally concave and forwardly vertically convex,
flexibly
resilient body portion 208, and an integral support portion 210 extending
upwardly from
the body portion 208. In the illustrated example, the body portion 208 is
shaped such
that the body portion vertically tapers along the height thereof so as to
generally follow
the contours and shape of the aperture 194 of the comfort member 184. The
support
portion 210 is slidably received within the sleeve 206 of the comfort member
184 such
that the lumbar assembly 186 is vertically adjustable with respect to the
remainder of the
back support assembly 99 between a fully lowered position I and a fully raised
position J.
A pawl member 212 selectively engages a plurality of apertures 214 spaced
along the
13
CA 02881887 2015-02-12
WO 2014/047255 PCT/US2013/060560
length of support portion 210, thereby releasably securing the lumbar assembly
186 at
selected vertical positions between the fully lowered position I and the fully
raised
position J. The pawl member 212 (Figs. 16a and 16b) includes a housing portion
216
having engagement tabs 218 located at the ends thereof and rearwardly offset
from an
outer surface 220 of the housing portion 216. A flexibly resilient finger 222
is centrally
disposed within the housing portion 216 and includes a rearwardly-extending
pawl 224.
[00100] In assembly, the pawl member 212 (Fig. 17) is positioned within an
aperture 226
located within the upper portion 188 of the comfort member 184 such that the
outer
surface 220 of the housing portion 216 of the pawl member 212 is coplanar with
the
forward surface 193 of the comfort member 184, and such that the engagement
tabs 218
of the housing portion 216 abut the rearward surface 195 of the comfort member
184.
The support portion 210 of the lumbar assembly 186 is then positioned within
the sleeve
206 of the comfort member 184 such that the sleeve 206 is slidable therein and
the pawl
224 is selectively engageable with the apertures 214, thereby allowing the
user to
optimize the position of the lumbar assembly 186 with respect to the overall
back
support assembly 99. Specifically, the body portion 208 of the lumbar assembly
186
includes a pair of outwardly extending integral handle portions 251 (Figs. 18A
and 18B)
each having a C-shaped cross-sectional configuration defining a channel 253
therein that
wraps about and guides along the respective side edge 192 of the comfort
member 184
and the side edge 118 of the back shell 112.
[00101] In operation, a user adjusts the relative vertical position of the
lumbar assembly
186 with respect to the back shell 112 by grasping one or both of the handle
portions 251
and sliding the handle assembly 251 along the comfort member 184 and the back
shell
112 in a vertical direction. A stop tab 228 is integrally formed within a
distal end 230 and
is offset therefrom so as to engage an end wall of the sleeve 206 of the
comfort member
184, thereby limiting the vertical downward travel of the support portion 210
of the
lumbar assembly 186 with respect to the sleeve 206 of the comfort member 184.
[00102] The back assembly 99 (Figs. 9A and 9B) also includes a cushion
member 252
having an upper portion 254 and a lower portion 256, wherein the lower portion
256
tapers along the vertical length thereof to correspond to the overall shape
and taper of
the back shell 112 and the comfort member 184.
14
CA 02881887 2015-02-12
WO 2014/047255 PCT/US2013/060560
[00103] The seat assembly 16 and the back assembly 18 are operably coupled
to and
controlled by the control assembly 14 (Fig. 19) and a control input assembly
260. The
control assembly 14 (Figs. 20-22) includes a housing or base structure or
ground
structure 262 that includes a front wall 264, a rear wall 266, a pair of side
walls 268 and a
bottom wall 270 integrally formed with one another and that cooperate to form
an
upwardly opening interior space 272. The bottom wall 270 includes an aperture
273
centrally disposed therein for receiving the cylinder assembly 28 (Fig. 3)
therethrough, as
described below. The base structure 262 further defines an upper and forward
pivot
point 274, a lower and forward pivot point 276, and an upper and rearward
pivot point
278, wherein the control assembly 14 further includes a seat support structure
282 that
supports the seat assembly 16. In the illustrated example, the seat support
structure 282
has a generally U-shaped plan form configuration that includes a pair of
forwardly
extending arm portions 284 each including a forwardly located pivot aperture
286
pivotably secured to the base structure 262 by a pivot shaft 288 for pivoting
movement
about the upper and forward pivot point 274. The seat support structure 282
further
includes a rear portion 290 extending laterally between the arm portions 284
and
cooperating therewith to form an interior space 292 within which the base
structure 262
is received. The rear portion 290 includes a pair of rearwardly extending arm
mounting
portions 294 to which the arm assemblies 20 are attached as described below.
The seat
support structure 282 further includes a control input assembly mounting
portion 296 to
which the control input assembly 260 is mounted. The seat support structure
282 further
includes a pair of bushing assemblies 298 that cooperate to define a pivot
point 300.
[00104] The control assembly 14 further includes a back support structure
302 having a
generally U-shaped plan view configuration and including a pair of forwardly
extending
arm portions 304 each including a pivot aperture 305 and pivotably coupled to
the base
structure 262 by a pivot shaft 307 such that the back support structure 302
pivots about
the lower and forward pivot point 276. The back support structure 302 includes
a rear
portion 308 that cooperates with the arm portions 304 to define an interior
space 310
which receives the base structure 262 therein. The back support structure 302
further
includes a pair of pivot apertures 312 located along the length thereof and
cooperating
to define a pivot point 314. It is noted that in certain instances, at least a
portion of the
back frame assembly 98 may be included as part of the back support structure
302.
CA 02881887 2015-02-12
WO 2014/047255 PCT/US2013/060560
[00105] The control assembly 14 further includes a plurality of control
links 316 each
having a first end 318 pivotably coupled to the seat support structure 282 by
a pair of
pivot pins 321 for pivoting about the pivot point 300, and a second end 322
pivotably
coupled to corresponding pivot apertures 312 of the back support structure 302
by a pair
of pivot pins 324 for pivoting about the pivot point 314. In operation, the
control links
316 control the motion, and specifically the recline rate of the seat support
structure 282
with respect to the back support structure 302 as the chair assembly is moved
to the
recline position, as described below.
[00106] As best illustrated in Figs. 23A and 23B, a bottom frame portion
102 of the back
frame assembly 98 is configured to connect to the back support structure 302
via a quick
connect arrangement 326. Each arm portion 304 of the back support structure
302
includes a mounting aperture 328 located at a proximate end 330 thereof. In
the
illustrated example, the quick connect arrangement 326 includes a
configuration of the
bottom frame portion 102 of the back frame assembly 98 to include a pair of
forwardly-
extending coupler portions 332 that cooperate to define a channel 334
therebetween
that receives the rear portion 308 and the proximate ends 330 of the arm
portions 304
therein. Each coupler portion 332 includes a downwardly extending boss 336
that aligns
with and is received within a corresponding aperture 328. Mechanical
fasteners, such as
screws 338 are then threaded into the bosses 336, thereby allowing a quick
connection
of the back frame assembly 98 to the control assembly 14.
[00107] As best illustrated in Fig. 24, the base structure 262, the seat
support structure
282, the back support structure 302 and the control links 316 cooperate to
form a 4-bar
linkage assembly that supports the seat assembly 16, the back assembly 18, and
the arm
assemblies 20. For ease of reference, the associated pivot assemblies
associated with
the 4-bar linkage assembly of the control assembly 14 are referred to as
follows: the
upper and forward pivot point 274 between the base structure 262 and the base
support
structure 282 as the first pivot point 274; the lower and forward pivot point
276 between
the base structure 262 and the back support structure 302 as the second pivot
point 276;
the pivot point 300 between the first end 318 of the control link 316 and the
seat support
structure 282 as the third pivot point 300; and, the pivot point 314 between
the second
end 322 of the control link 316 and the back support structure 302 as the
fourth pivot
point 314. Further, Figure 24 illustrates the component of the chair assembly
10 shown
16
CA 02881887 2015-02-12
WO 2014/047255 PCT/US2013/060560
in a reclined position in dashed lines, wherein the reference numerals of the
chair in the
reclined position are designated with a " ' ".
[00108] In operation, the 4-bar linkage assembly of the control assembly
14 cooperates to
recline the seat assembly 16 from the upright position G to the reclined
position H as the
back assembly 184 is moved from the upright position E to the reclined
position F,
wherein the upper and lower representations of the positions E and F in Fig.
24 illustrate
that the upper and lower portions of the back assembly 18 reclines as a single
piece.
Specifically, the control link 316 is configured and coupled to the seat
support structure
282 and the back support structure 302 to cause the seat support structure 282
to rotate
about the first pivot point 274 as the back support structure 302 is pivoted
about the
second pivot point 276. Preferably, the seat support structure 302 is rotated
about the
first pivot point 274 at between about 1/3 and about 2/3 the rate of rotation
of the back
support structure 302 about the second pivot point 276, more preferably the
seat
support structure rotates about the first pivot point 274 at about half the
rate of rotation
of the back support structure 302 about the second pivot point 276, and most
preferably
the seat assembly 16 reclines to an angle 13 of about 9 from the fully
upright position G
to the fully reclined position H, while the back assembly 18 reclines to an
angle y of about
18 from the fully upright position E to the fully reclined position F.
[00109] As best illustrated in Fig. 24, the first pivot point 274 is
located above and forward
of the second pivot point 276 when the chair assembly 10 is at the fully
upright position,
and when the chair assembly 10 is at the fully reclined position as the base
structure 262
remains fixed with respect to the supporting floor surface 13 as the chair
assembly 10 is
reclined. The third pivot point 300 remains behind and below the relative
vertical height
of the first pivot point 274 throughout the reclining movement of the chair
assembly 10.
It is further noted that the distance between the first pivot point 274 and
the second
pivot point 276 is greater than the distance between the third pivot point 300
and the
fourth pivot point 314 throughout the reclining movement of the chair assembly
10. As
best illustrated in Fig. 25, a longitudinally extending center line axis 340
of the control
link 316 forms an acute angle a with the seat support structure 282 when the
chair
assembly 10 is in the fully upright position and an acute angle a' when the
chair assembly
is in the fully reclined position. It is noted that the center line axis 340
of the control
link 316 does not rotate past an orthogonal alignment with the seat support
structure
17
CA 02881887 2015-02-12
WO 2014/047255 PCT/US2013/060560
282 as the chair assembly 10 is moved between the fully upright and fully
reclined
positions thereof.
[00110] With further reference to Fig. 26, a back control link 342 includes
a forward end
that is pivotably connected to the seat support structure 282 at a fifth pivot
point 344. A
rearward end 345 of the back control link 342 is connected to the lower
portion 116 of
the back shell 112 at a sixth pivot point 346. The sixth pivot point 346 is
optional, and the
back control link 342 and the back shell 112 may be rigidly fixed to one
another. Also,
the pivot point 346 may include a stop feature that limits rotation of the
back control link
342 relative to the back shell 112 in a first and/or second rotational
direction. For
example, with reference to Fig. 26, the pivot 346 may include a stop feature
that permits
clockwise rotation of the lower portion 116 of the back shell 112 relative to
the control
link 342. This permits the lumbar to become flatter if a rearward/horizontal
force
tending to reduce dimension D1 is applied to the lumbar portion of the back
shell 112.
However, the stop feature may be configured to prevent rotation of the lower
portion
116 of the back shell 112 in a counter clockwise direction (Fig. 26) relative
to the control
link 342. This causes the link 342 and the lower portion 116 of the back shell
112 to
rotate at the same angular rate as the back assembly 18 when a user reclines
in the chair
by pushing against an upper portion of the back assembly 18.
[00111] A cam link 350 is also pivotably connected to the seat support
structure 282 for
rotation about the pivot point or axis 344. The cam link 350 has a curved
lower cam
surface 352 that slidably engages an upwardly facing cam surface 354 formed in
the back
support structure 302. A pair of torsion springs 356 (see also Figs. 18A and
18B) rotatably
bias the back control link 342 and the cam link 350 in a manner that tends to
increase the
angle 0 (Fig. 26). The torsion springs 356 generate a force tending to rotate
the control
link 342 in a counter-clockwise direction (Fig. 26), and simultaneously rotate
the cam link
350 in a clockwise direction (Fig. 26). Thus, the torsion springs 356 tend to
increase the
angle 0 between back the control link 342 and the cam link 350. A stop 348 on
the seat
support structure 282 limits counter clockwise rotation of the back control
link 342 to the
position shown in Fig. 26. This force may also bias the control link 342 in a
counter
clockwise direction into the stop feature.
[00112] As discussed above, the back shell 112 is flexible, particularly in
comparison to the
rigid back frame structure 98. As also discussed above, the back frame
structure 98 is
18
CA 02881887 2015-02-12
WO 2014/047255 PCT/US2013/060560
rigidly connected to the back support structure 302, and therefore pivots with
the back
support structure 302. The forces generated by the torsion springs 356 push
upwardly
against the lower portion 116 of the back shell 112. As also discussed above,
the slots
128 in the back shell structure 112 create additional flexibility at the
lumbar support
portion 126 of the back shell 112. The force generated by the torsion springs
356 also
tends to cause the lumbar portion 126 of the back shell 112 to bend forwardly
such that
the lumbar portion 126 has a higher curvature than the regions adjacent the
lumbar
portion 126.
[00113] As discussed above, the position of the lumbar assembly 186 is
vertically
adjustable. Vertical adjustment of the lumbar assembly 186 also adjusts the
way in
which the back shell 112 flexes/curves during recline of the chair back. In
Fig. 26, the
lumbar assembly 186 is adjusted to an intermediate or neutral position, such
that the
curvature of the lumbar portion 126 of the back shell 112 is also intermediate
or neutral.
With further reference to Fig. 27, if the vertical position of the lumbar
assembly 186 is
adjusted, the angle 0 is reduced, and the curvature of the lumbar region 126
is reduced.
As shown in Fig. 27, this also causes angle 01 to become greater, and the
overall shape of
the back shell 112 to become relatively flat.
[00114] With further reference to Fig. 28, if the height of the lumbar
assembly 186 is set
at an intermediate level (i.e., the same as Fig. 26), and a user leans back,
the 4-bar
linkage defined by the links and the structures 262, 282, 302, 316, and the
pivot points
274, 276, 300, 314 will shift (as described above) from the configuration of
Fig. 26 to the
configuration of Fig 28. This, in turn, causes an increase in the distance
between the
pivot point 344 and the cam surface 354. This causes an increase in the angle
0 from
about 49.5 (Fig. 26) to about 59.9 (Fig. 28). As the spring rotates toward
an open
position, some of the energy stored in the spring is transferred into the back
shell 112,
thereby causing the degree of curvature of the lumbar portion 116 of the back
shell 112
to become greater. In this way, the back control link 342, the cam link 350,
and the
torsion springs 356 provide for greater curvature of the lumbar region 116 to
reduce the
curvature of a user's back as the user leans back in the chair.
[00115] Also, as the chair tilts from the position of Fig. 26 to the
position of Fig. 28, the
distance D between the lumbar region 126 and the seat 16 increases from 174mm
to
234mm. A dimension D1 between the lumbar region 126 of the back shell 112 and
the
19
CA 02881887 2015-02-12
WO 2014/047255 PCT/US2013/060560
back frame structure 98 also increases as the back tilts from the position of
Fig. 26 to the
position of Fig. 28. Thus, although the distance D increases somewhat, the
increase in
the dimension D1 reduces the increase in dimension D because the lumbar region
126 of
the back shell 112 is shifted forward relative to the back frame 98 during
recline.
[00116] Referring again to Fig. 26, a spine 360 of a seated user 362 tends
to curve
forwardly in the lumbar region 364 by a first amount when a user is seated in
an upright
position. As a user leans back from the position of Fig. 26 to the position of
Fig. 28, the
curvature of the lumbar region 364 tends to increase, and the user's spine 360
will also
rotate somewhat about hip joint 366 relative to a user's femur 368. The
increase in the
dimension D and the increase in curvature of the lumbar region 126 of the back
shell 112
simultaneously ensure that a user's hip joint 366 and femur 368 do not slide
on the seat
16, and also accommodate curvature of the lumbar region 364 of a user's spine
360.
[00117] As discussed above, Fig. 27 shows the back assembly 18 of the
chair assembly 10
in an upright position with the lumbar region 126 of the back shell 112
adjusted to a flat
position. If the back assembly 18 is tilted from the position of Fig. 27 to
the position of
Fig. 29, the back control link 342 and the cam link 350 both rotate in a
clockwise
direction. However, the cam link 350 rotates at a somewhat higher rate, and
the angle 0
therefore changes from 31.4 to 35.9 . The distance D changes from 202mm to
265mm,
and the angle 01 changes from 24.2 to 24.1 .
[00118] With further reference to Fig. 29A, if the back assembly 18 is
reclined, and the
lumbar adjustment is set high, the angle 0 is 93.6 , and the distance D is
202mm.
[00119] Thus, the back shell 112 curves as the seat back is tilted
rearwardly. However, the
increase in curvature in the lumbar region 126 from the upright to the
reclined position is
significantly greater if the curvature is initially adjusted to a higher
level. This accounts
for the fact that the curvature of a user's back does not increase as much
when a user
reclines if the user's back is initially in a relatively flat condition when
seated upright.
Restated, if a user's back is relatively straight when in an upright position,
the user's back
will remain relatively flat even when reclined, even though the degree of
curvature will
increase somewhat from the upright position to the reclined position.
Conversely, if a
user's back is curved significantly when in the upright position, the
curvature of the
lumbar region will increase by a greater degree as the user reclines relative
to the
increase in curvature if a user's back is initially relatively flat.
CA 02881887 2015-02-12
WO 2014/047255 PCT/US2013/060560
[00120] A pair of spring assemblies 442 (Figs. 20 and 21) bias the back
assembly 18 from
the reclined position F towards the upright position E. As best illustrated in
Fig. 22, each
spring assembly 442 includes a cylindrically-shaped housing 444 having a first
end 446
and a second end 448. Each spring assembly 442 further includes a compression
coil
spring 450, a first coupler 452 and a second coupler 454. In the illustrated
example, the
first coupler is secured to the first end 446 of the housing 444, while the
second coupler
454 is secured to a rod member 456 that extends through the coil spring 450. A
washer
457 is secured to a distal end of the rod member 458 and abuts an end of the
coil spring
450, while the opposite end of the coil spring 450 abuts the second end 448 of
the
housing 444. The first coupler 452 is pivotably secured to the back support
structure 302
by a pivot pin 460 for pivoting movement about a pivot point 461, wherein the
pivot pin
460 is received within pivot apertures 462 of the back support structure 302,
while the
second coupler 454 is pivotably coupled to a moment arm shift assembly 466
(Figs. 30-
32) by a shaft 464 for pivoting about a pivot point 465. The moment arm shift
assembly
is adapted to move the biasing or spring assembly 442 from a low tension
setting (Fig.
33A) to a high tension setting (Fig. 34A) wherein the force exerted by the
biasing
assembly 442 on the back assembly 18 is increased relative to the low-tension
setting.
[00121] As illustrated in Figs. 30A-32, the moment arm shift assembly 466
includes an
adjustment assembly 468, a moment arm shift linkage assembly 470 operably
coupling
the control input assembly 260 to the adjustment assembly 468 and allowing the
operator to move the biasing assembly 442 between the low and high tension
settings,
and an adjustment assist assembly 472 that is adapted to reduce the amount of
input
force required to be exerted by the user on the control input assembly 260 to
move the
moment arm shift assembly 466 from the low tension setting to the high tension
setting,
as described below.
[00122] The adjustment assembly 468 comprises a pivot pin 467 that includes
a threaded
aperture that threadably receives a threaded adjustment shaft 476 therein. The
adjustment shaft 476 includes a first end 478 and a second end 484, wherein
the first end
478 extends through an aperture 480 of the base structure 262 and is guided
for pivotal
rotation about a longitudinal axis by a bearing assembly 482. The pivot pin
467 is
supported from the base structure 262 by a linkage assembly 469 that includes
a pair of
linkage arms 471 each having a first end 473 pivotably coupled to the second
coupler 454
21
CA 02881887 2015-02-12
WO 2014/047255 PCT/US2013/060560
by the pivot pin 464 and a second end 475 pivotably coupled to the base
structure 262 by
a pivot pin 477 pivotably received within a pivot aperture 479 of the base
structure 262
for pivoting about a pivot point 481, and an aperture 483 that receives a
respective end
of the pivot pin 467. The pivot pin 467 is pivotably coupled with the linkage
arms 471
along the length thereof.
[00123] The moment arm shift linkage assembly 470 (Figs. 30A and 30B)
includes a first
drive shaft 486 extending between the control input assembly 260 and a first
beveled
gear assembly 488, and a second drive shaft 490 extending between and operably
coupling the first beveled gear assembly 488 with a second beveled gear
assembly 492,
wherein the second beveled gear assembly 492 is connected to the adjustment
shaft 476.
The first drive shaft 486 includes a first end 496 operably coupled to the
control input
assembly 260 by a first universal joint assembly 498, while the second end 500
of the first
drive shaft 486 is operably coupled to the first beveled gear assembly 488 by
a second
universal joint assembly 502. In the illustrated example, the first end 496 of
the first
drive shaft 486 includes a female coupler portion 504 of the first universal
joint assembly
498, while the second end 500 of the first drive shaft 486 includes a female
coupler
portion 506 of the second universal joint assembly 502. The first beveled gear
assembly
488 includes a housing assembly 508 that houses a first beveled gear 510 and a
second
beveled gear 512 therein. As illustrated, the first beveled gear 510 includes
an integral
male coupler portion 514 of the second universal joint 502. The first end 496
of the
second drive shaft 490 is coupled to the first beveled gear assembly 488 by a
third
universal joint assembly 516. A first end 518 of the second drive shaft 490
includes a
female coupler portion 520 of the third universal joint assembly 516. The
second
beveled gear 512 includes an integral male coupler portion 522 of the third
universal
joint assembly 516. A second end 524 of the second drive shaft 490 includes a
plurality
of longitudinally extending splines 526 that mate with corresponding
longitudinally
extending splines (not shown) of a coupler member 528. The coupler member 528
couples the second end 524 of the second drive shaft 490 with the second
beveled gear
assembly 492 via a fourth universal joint assembly 530. The fourth universal
joint
assembly 530 includes a housing assembly 532 that houses a first beveled gear
534
coupled to the coupler member 528 via the fourth universal joint assembly 530,
and a
second beveled gear 536 fixed to the second end 484 of the adjustment shaft
476. The
22
CA 02881887 2015-02-12
WO 2014/047255 PCT/US2013/060560
coupler member 428 includes a female coupler portion that receives a male
coupler
portion 540 integral with the first beveled gear 534.
[00124] In assembly, the adjustment assembly 468 of the moment arm shift
assembly 466
is operably supported by the base structure 262, while the control input
assembly 260 is
operably supported by the control input assembly mounting portion 296 of the
seat
support structure 282. As a result, the relative angles and distances between
the control
input assembly 260 and the adjustment assembly 468 of the moment arm shift
assembly
466 change as the seat support structure 282 is moved between the fully
upright position
G and the fully reclined H. The third and fourth universal joint assemblies
516, 530, and
the spline assembly between the splines cooperate to compensate for these
relative
changes in angle and distance.
[00125] As is best illustrated in Figs. 33A-34B, the moment arm shift
assembly 466
functions to adjust the biasing assemblies 442 between the low-tension and
high-tension
settings. Specifically, the biasing assemblies 442 are shown in a low-tension
setting with
the chair assembly 10 in an upright position in Fig. 33A, and the low-tension
setting with
the chair assembly 10 in a reclined position in Fig. 33B, while Fig. 34A
illustrates the
biasing assemblies 442 in the high-tension setting with the chair in an
upright position,
and Fig. 34B the biasing assemblies is in the high-tension setting with the
chair assembly
in the reclined position. The distance 542, as measured between the pivot
point 465
and the second end 448 of the housing 444 of the spring assembly 442, serves
as a
reference to the amount of compression exerted on the spring assembly 442 when
the
moment arm shift assembly 466 is positioned in the low-tension setting and the
chair is
in the upright position. The distance 542' (Fig. 33B) comparatively
illustrates the
increased amount of compressive force exerted on the spring assembly 442 when
the
moment arm shift assembly 466 is in the high-tension setting and the chair is
in the
upright position. The user adjusts the amount of force exerted by the biasing
assemblies
442 on the back support structure 302 by moving the moment arm shift assembly
466
from the low-tension setting to the high-tension setting. Specifically, the
operator,
through an input to the control input assembly 260, drives the adjustment
shaft 476 of
the adjustment assembly 468 in rotation via the moment arm shift linkage
assembly 470,
thereby causing the pivot shaft 467 to travel along the length of the
adjustment shaft
476, thus changing the compressive force exerted on the spring assemblies 442
as the
23
CA 02881887 2015-02-12
WO 2014/047255 PCT/US2013/060560
pivot shaft 467 is adjusted with respect to the base structure 262. The pivot
shaft 467
travels within a slot 544 located within a side plate member 546 attached to a
side wall
268 of the base structure 262. It is noted that the distance 542 when the
moment arm
shift assembly 466 is in the high-tension setting and the chair assembly 10 is
in the
upright position is greater than the distance 542 when the moment arm shift
466 is in the
low-tension setting and the chair is in the upright position, thereby
indicating that the
compressive force as exerted on the spring assemblies 442, is greater when the
moment
arm shift is in the high-tension setting as compared to a low-tension setting.
Similarly,
the distance 543 (Fig. 33B) is greater than the distance 543' (Fig. 34B),
resulting in an
increase in the biasing force exerted by the biasing assemblies 442 and
forcing the back
assembly 18 from the reclined position towards the upright position. It is
noted that the
change in the biasing force exerted by the biasing assemblies 442 corresponds
to a
change in the biasing torque exerted about the second pivot point 276, and
that in
certain configurations, a change in the biasing torque is possible without a
change in the
length of the biasing assemblies 442 or a change in the biasing force.
[00126] Figure 35 is a graph of the amount of torque exerted about the
second pivot point
276 forcing the back support structure 302 from the reclined position towards
the
upright position as the back support structure 302 is moved between the
reclined and
upright positions. In the illustrated example, the biasing assemblies 442
exert a torque
about the second pivot point 276 of about 652 inch-pounds when the back
support
structure is in the upright position and the moment arm shift 466 is in the
low tension
setting, and of about 933 inch-pounds when the back support structure is in
the reclined
position and the moment arm shift 466 is in the low tension setting, resulting
in a change
of approximately 43%. Likewise, the biasing assemblies 442 exert a torque
about the
second pivot point 274 of about 1.47E+03 inch-pounds when the back support
structure
is in the upright position and the moment arm shift 466 is in the high tension
setting, and
of about 2.58E+03 inch-pounds when the back support structure is in the
reclined
position and the moment arm shift 466 is in the high tension setting,
resulting in a
change of approximately 75%. This significant change in the amount of torque
exerted
by the biasing assembly 442 between the low tension setting and the high
tension setting
of the moment arm shift 466 as the back support structure 302 is moved between
the
24
CA 02881887 2015-02-12
WO 2014/047255 PCT/US2013/060560
upright and reclined positions allows the overall chair assembly 10 to provide
proper
forward back support to users of varying height and weight.
[00127] The adjustment assist assembly 472 assists an operator in moving
the moment
arm shift assembly 466 from the high-tension setting to the low-tension
setting. The
adjustment assist assembly 472 includes a coil spring 548 secured to the front
wall 264 of
the base structure 262 by a mounting structure 550, and a catch member 552
that
extends about the shaft 306 fixed with the linkage arms 471, and that includes
a catch
portion 556 defining an aperture 558 that catches a free end 560 of the coil
spring 548.
The coil spring 548 exerts a force F on the catch member 552 and shaft 306 and
the
linkage arms 471 in an upward vertical direction, thereby reducing the amount
of input
force the user must exert on the control input assembly 260 to move the moment
arm
shift assembly 466 from the low-tension setting to the high-tension setting.
[00128] As noted above, the seat assembly 16 is longitudinally shiftable
with respect to
the control assembly 14 between a retracted position C and an extended
position D (Fig.
3). As best illustrated in Figs. 19, 36 and 37, a direct drive assembly 562
includes a drive
assembly 564 and a linkage assembly 566 that couples the control input
assembly 260
with the drive assembly 564, thereby allowing a user to adjust the linear
position of the
seat by adjusting the linear position of the seat assembly 16 with respect to
the control
assembly 14. In the illustrated example, the seat support plate 32 includes
the C-shaped
guiderails 38 which wrap about and slidably engage corresponding guide flanges
570 of a
control plate 572 of the control assembly 14. A pair of C-shaped,
longitudinally extending
connection rails 574 are positioned within the corresponding guiderails 38 and
are
coupled with the seat support plate 32. A pair of C-shaped bushing members 576
extend
longitudinally within the connection rails 574 and are positioned between the
connection
rails 574 and the guide flanges 570. The drive assembly 564 includes a rack
member 578
having a plurality of downwardly extending teeth 580. The drive assembly 564
further
includes a rack guide 582 having a C-shaped cross-sectional configuration
defining a
channel 584 that slidably receives the rack member 578 therein. The rack guide
582
includes a relief 586 located along the length thereof that matingly receives
a bearing
member 588 therein. Alternatively, the bearing member 588 may be formed as an
integral portion of the rack guide 582. The drive assembly 564 further
includes a drive
shaft 590 having a first end universally coupled with the control input
assembly 260 and
CA 02881887 2015-02-12
WO 2014/047255 PCT/US2013/060560
the second end 594 having a plurality of radially-spaced teeth 596. In
assembly, the seat
support plate 32 is slidably coupled with the control plate 572 as described
above, with
the rack member 578 being secured to an underside of the seat support plate 32
and the
rack guide 582 being secured within an upwardly opening channel 598 of the
control
plate 572. In operation, an input force exerted by the user to the control
input assembly
260 is transferred to the drive assembly 564 via the linkage assembly 566,
thereby driving
the teeth 596 of the drive shaft 590 against the teeth 580 of the rack member
578 and
causing the rack member 578 and the seat support plate 32 to slide with
respect to the
rack guide 582 and the control plate 572.
[00129] With further reference to Figs. 38-40, the chair assembly 10
includes a height
adjustment assembly 600 that permits vertical adjustment of seat 16 and back
18 relative
to the base assembly 12. Height adjustment assembly 600 includes a pneumatic
cylinder
28 that is vertically disposed in central column 26 of base assembly 12 in a
known
manner.
[00130] A bracket structure 602 is secured to housing or base structure
262, and upper
end portion 604 of pneumatic cylinder 28 is received in opening 606 of base
structure
262 in a known manner. Pneumatic cylinder 28 includes an adjustment valve 608
that
can be shifted down to release pneumatic cylinder 28 to provide for height
adjustment.
A bell crank 610 has an upwardly extending arm 630 and a horizontally
extending arm
640 that is configured to engage a release valve 608 of pneumatic cylinder 28.
Bell crank
610 is rotatably mounted to bracket 602. A cable assembly 612 operably
interconnects
bell crank 610 with adjustment wheel/lever 620. Cable assembly 612 includes an
inner
cable 614 and an outer cable or sheath 616. Outer sheath 616 includes a
spherical ball
fitting 618 that is rotatably received in a spherical socket 622 formed in
bracket 602. A
second ball fitting 624 is connected to end 626 of inner cable 614. Second
ball fitting 624
is rotatably received in a second spherical socket 628 of upwardly extending
arm 630 of
bell crank 610 to permit rotational movement of the cable end during height
adjustment.
[00131] A second or outer end portion 632 of inner cable 614 wraps around
wheel 620,
and an end fitting 634 is connected to inner cable 614. A tension spring 636
is connected
to end fitting 634 and to the seat structure at point 638. Spring 636
generates tension on
inner cable 614 in the same direction that cable 614 is shifted to rotate bell
crank 610
when valve 608 is being released. Although spring 636 does not generate enough
force
26
CA 02881887 2015-02-12
WO 2014/047255 PCT/US2013/060560
to actuate valve 608, spring 636 does generate enough force to bias arm 640 of
bell crank
610 into contact with valve 608. In this way, lost motion or looseness that
could
otherwise exist due to tolerances in the components is eliminated. During
operation, a
user manually rotates adjustment wheel 620, thereby generating tension on
inner cable
614. This causes bell crank 610 to rotate, causing arm 640 of bell crank 610
to press
against and actuate valve 608 of pneumatic cylinder 28. An internal spring
(not shown)
of pneumatic cylinder 28 biases valve 608 upwardly, causing valve 608 to shift
to a non-
actuated position upon release of adjustment wheel 620.
[00132] The control input assembly 260 (Figs. 19 and 41-43) comprises a
first control input
assembly 700 and a second control input assembly 702 each adapted to
communicate
inputs from the user to the chair components and features coupled thereto, and
housed
within a housing assembly 704. The control input assembly 260 includes an anti-
back
drive assembly 706, an overload clutch assembly 708, and a knob 710. The anti-
back
drive mechanism or assembly 706 that prevents the direct drive assembly 562
(Figs. 36
and 37) and the seat assembly 16 from being driven between the retracted and
extended
positions C, D without input from the control assembly 700. The anti-back
drive
assembly 706 is received within an interior 712 of the housing assembly 704
and includes
an adaptor 714 that includes a male portion 716 of a universal adaptor coupled
to the
second end 594 of the drive shaft 590 (Fig. 37) at one end thereof, and
including a spline
connector 717 at the opposite end. A cam member 718 is coupled with the
adaptor 714
via a clutch member 720. Specifically, the cam member 718 includes a spline
end 722
coupled for rotation with the knob 710, and a cam end 724 having an outer cam
surface
726. The clutch member 720 includes an inwardly disposed pair of splines 723
that
slidably engage the spline connector 717 having a cam surface 730 that
cammingly
engages the outer cam surface 726 of the cam member 718, as described below.
The
clutch member 720 has a conically-shaped clutch surface 719 that is engagingly
received
by a locking ring 732 that is locked for rotation with respect to the housing
assembly 704
and includes a conically-shaped clutch surface 721 corresponding to the clutch
surface
719 of the clutch member 720, and cooperating therewith to form a cone clutch.
A coil
spring 734 biases the clutch member 720 towards engaging the locking ring 732.
[00133] Without input, the biasing spring 734 forces the conical surface of
the clutch
member 720 into engagement with the conical surface of the locking ring 732,
thereby
27
CA 02881887 2015-02-12
WO 2014/047255 PCT/US2013/060560
preventing the "back drive" or adjustment of the seat assembly 16 between the
retracted
and extended positions C, D, simply by applying a rearward or forward force to
the seat
assembly 16 without input from the first control input assembly 700. In
operation, an
operator moves the seat assembly 16 between the retracted and extended
positions C, D
by actuating the direct drive assembly 562 via the first control input
assembly 700.
Specifically, the rotational force exerted on the knob 710 by the user is
transmitted from
the knob 710 to the cam member 718. As the cam member 718 rotates, the outer
cam
surface 726 of the cam member 718 acts on the cam surface 730 of the clutch
member
720, thereby overcoming the biasing force of the spring 734 and forcing the
clutch
member 720 from an engaged position, wherein the clutch member 720 disengages
the
locking ring 732. The rotational force is then transmitted from the cam member
718 to
the clutch member 720 and then to the adaptor 714, which is coupled to the
direct drive
assembly 762 via the linkage assembly 566.
[00134] It is noted that a slight amount of tolerance within the first
control input assembly
700 allows a slight movement (or "slop") of the cam member 718 in the linear
direction
and rotational direction as the clutch member 720 is moved between the engaged
and
disengaged positions. A rotational ring-shaped damper element 736 comprising a
thermoplastic elastomer (TPE), is located within the interior 712 of the
housing 704, and
is attached to the clutch member 720. In the illustrated example, the damper
element
736 is compressed against and frictionally engages the inner wall of the
housing assembly
704.
[00135] The first control input assembly 700 also includes a second knob
738 adapted to
allow a user to adjust the vertical position of the chair assembly between the
lowered
position A and the raised position B, as described below.
[00136] The second control input assembly 702 is adapted to adjust the
tension exerted
on the back assembly 18 during recline, and to control the amount of recline
of the back
assembly 18. A first knob 740 is operably coupled to the moment arm shift
assembly 466
by the moment arm shift linkage assembly 470. Specifically, the second control
input
assembly 702 includes a male universal coupling portion 742 that couples with
the
female universal coupler portion 504 (Figs. 30 and 31) of the shaft 486 of the
moment
arm shift linkage assembly 470.
28
CA 02881887 2015-02-12
WO 2014/047255 PCT/US2013/060560
[00137] A second knob 760 is adapted to adjust the amount of recline of the
back
assembly 18 via a cable assembly 762 operably coupling the second knob 760 to
a
variable back stop assembly 764 (Fig. 43). The cable assembly 762 includes a
first cable
routing structure 766, a second cable routing structure 768 and a cable tube
770
extending therebetween and slidably receiving an actuator cable 772 therein.
The cable
772 includes a distal end 774 that is fixed with respect to the base structure
262, and is
biased in a direction 776 by a coil spring 778. The variable back stop
assembly 764
includes a stop member 780 having a plurality of vertically graduated steps
782, a
support bracket 784 fixedly supported with respect to the seat assembly 16,
and a slide
member 786 slidably coupled to the support bracket 784 to slide in a fore-to-
aft direction
788 and fixedly coupled to the stop member 780 via a pair of screws 790. The
cable 772
is clamped between the stop member 780 and the slide member 786 such that
longitudinal movement of the cable 772 causes the stop member 780 to move in
the
fore-and-aft direction 788. In operation, a user adjusts the amount of back
recline
possible by adjusting the location of the stop member 780 via an input to the
second
knob 760. The amount of back recline available is limited by which select step
782 of the
stop member 780 contacts a rear edge 792 of the base structure 262 as the back
assembly 18 moves from the upright towards the reclined position.
[00138] Each arm assembly 20 (Figs. 44-46) includes an arm support assembly
800
pivotably supported from an arm base structure 802, and adjustably supporting
an
armrest assembly 804. The arm support assembly 800 includes a first arm member
806, a
second arm 808, an arm support structure 810, and an armrest assembly support
member 812 that cooperate to form a 4-bar linkage assembly. In the illustrated
example,
the first arm member 806 has a U-shaped cross-sectional configuration and
includes a
first end 814 pivotably coupled to the arm support structure 810 for pivoting
about a
pivot point 816, and a second end 818 pivotably coupled to the armrest
assembly
support member 812 for pivoting movement about a pivot point 820. The second
arm
member 808 has a U-shaped cross-sectional configuration and includes a first
end 822
pivotably coupled to the arm support structure 810 for pivoting about a pivot
point 824,
and a second end 826 pivotably coupled to the armrest assembly support member
812
for pivoting about a pivot point 828. As illustrated, the 4-bar linkage
assembly of the arm
support assembly 800 allows the armrest assembly 804 to be adjusted between a
fully
29
CA 02881887 2015-02-12
WO 2014/047255 PCT/US2013/060560
raised position K and a fully lowered position L, wherein the distance between
the fully
raised position K and fully lowered position L is preferably at least about 4
inches. Each
arm assembly further includes a first arm cover member 807 having a U-shaped
cross-
sectional configuration and including a first edge portion 809, and a second
arm cover
member 811 having a U-shaped cross-sectional configuration and including a
second
edge portion 813, wherein the first arm member 806 is housed within the first
arm cover
member 807 and the second arm member 808 is housed within the second arm cover
member 811, such that the second edge portion 813 overlaps with the first edge
portion
809.
[00139] Each arm base structure 802 includes a first end 830 connected to
the control
assembly 14, and a second end 832 pivotably supporting the arm support
structure 810
for rotation of the arm assembly 20 about a vertical axis 835 in a direction
837. The first
end 830 of the arm base structure 802 includes a body portion 833 and a
narrowed
bayonet portion 834 extending outwardly therefrom. In assembly, the body
portion 833
and bayonet portion 834 of the first end 830 of the arm base structure 802 are
received
between the control plate 572 and the seat support structure 282, and are
fastened
thereto by a plurality of mechanical fasteners (not shown) that extend through
the body
portion 833 and bayonet portion 834 of the arm-base structure 802, the control
plate
572 and the seat support structure 282. The second end 832 of the arm base
structure
802 pivotably receives the arm support structure 810 therein.
[00140] As best illustrated in Fig. 47, the arm base structure 802
includes an upwardly
opening bearing recess 836 having a cylindrically-shaped upper portion 838 and
a
conically-shaped lower portion 840. A bushing member 842 is positioned within
the
bearing recess 836 and is similarly configured as the lower portion 840 of the
bearing
recess 836, including a conically-shaped portion 846. The arm support
structure 810
includes a lower end having a cylindrically-shaped upper portion 848 and a
conically-
shaped lower portion 850 received within the lower portion 846 of the bushing
member
842. An upper end 852 of the arm support structure 810 is configured to
operably engage
within a vertical locking arrangement, as described below. A pin member 854 is
positioned within a centrally located and axially extending bore 856 of the
arm support
structure 810. In the illustrated example, the pin member 854 is formed from
steel,
while the upper end 852 of the arm support structure 810 comprises a powdered
metal
CA 02881887 2015-02-12
WO 2014/047255 PCT/US2013/060560
that is formed about a proximal end of the pin member 854, and wherein the
combination of the upper end 852 and the pin member 854 is encased within an
outer
aluminum coating. A distal end 853 of the pin member 854 includes an axially
extending
threaded bore 855 that threadably receives an adjustment screw 857 therein.
The arm
base structure 802 includes a cylindrically-shaped second recess 858 separated
from the
bearing recess 836 by a wall 860. A coil spring 864 is positioned about the
distal end 853
of the pin member 854 within the second recess 858, and is trapped between the
wall
860 of the arm base structure 802 and a washer member 866, such that the coil
spring
864 exerts a downward force in the direction of arrow 868 on the pin member
854,
thereby drawing the lower end of the arm support structure 810 into close
frictional
engagement with the bushing member 842 and drawing the bushing member 842 into
close frictional engagement with the bearing recess 836 of the arm base
structure 802.
The adjustment screw 857 may be adjusted so as to adjust the amount of
frictional
interference between the arm support structure 810, the bushing member 842 and
the
arm base structure 802 and increasing the force required to be exerted by the
user to
move the arm assembly 20 about the pivot access 835 in pivot direction 837.
The pivot
connection between the arm support structure 810 and the arm base structure
802
allows the overall arm assembly 800 to be pivoted inwardly in a direction 876
(Fig. 48)
from a line 874 extending through pivot access 835 and extending parallel with
a center
line axis 872 of the seat assembly 16, and outwardly from the line 874 in a
direction 878.
Preferably, the arm assembly 20 pivots greater than or equal to about 17 in
the direction
876 from the line 874, and greater than or equal to about 22 in the direction
878 from
the line 874.
[00141] With further reference to Figs. 49-51, vertical height adjustment
of the arm rest is
accomplished by rotating the 4-bar linkage formed by first arm member 806,
second arm
member 808, arm support structure 810 and arm rest assembly support member
812. A
gear member 882 includes a plurality of teeth 884 that are arranged in an arc
about pivot
point 816. A lock member 886 is pivotably mounted to arm 806 at pivot 888, and
includes a plurality of teeth 890 that selectively engage teeth 884 of gear
member 882.
When teeth 884 and 890 are engaged, the height of the arm rest 804 is fixed
due to the
rigid triangle formed between pivot points 816, 824 and 888. If a downward
force F4 is
applied to the armrest, a counter clockwise (Fig. 50) moment is generated on
lock
31
CA 02881887 2015-02-12
WO 2014/047255 PCT/US2013/060560
member 886. This moment pushes teeth 890 into engagement with teeth 884,
thereby
securely locking the height of the armrest.
[00142] An elongated lock member 892 is rotatably mounted to arm 806 at
pivot 894. A
low friction polymer bearing member 896 is disposed over upper curved portion
893 of
elongated lock member 892. As discussed in more detail below, a manual release
lever
or member 898 includes a pad 900 that can be shifted upwardly by a user to
selectively
release teeth 890 of lock member 886 from teeth 884 of gear member 882 to
permit
vertical height adjustment of the armrest.
[00143] A leaf spring 902 includes a first end 904 that engages a notch 906
formed in
upper edge 908 of elongated locking member 892. Thus, leaf spring 902 is
cantilevered
to locking member 892 at notch 906. An upwardly-extending tab 912 of elongated
locking member 892 is received in an elongated slot 910 of leaf spring 902 to
thereby
locate spring 902 relative to locking member 892. The end 916 of leaf spring
902 bears
upwardly (F1) on knob 918 of locking member 886, thereby generating a moment
tending to rotate locking member 886 in a clockwise (released) direction (Fig.
51) about
pivot 888. Leaf spring 902 also generates a clockwise moment on elongated
locking
member 892 at notch 906, and also generates a moment on locking member 886
tending
to rotate locking member 886 about pivot 888 in a clockwise (released)
direction. This
moment tends to disengage gears 890 from gears 884. If gears 890 are
disengaged from
gears 884, the height of the arm rest assembly can be adjusted.
[00144] Locking member 886 includes a recess or cut-out 920 (Fig. 50) that
receives
pointed end 922 of elongated locking member 892. Recess 920 includes a first
shallow V-
shaped portion having a vertex 924. The recess also includes a small recess or
notch 926,
and a transverse, upwardly facing surface 928 immediately adjacent notch 926.
[00145] As discussed above, the leaf spring 902 generates a moment acting
on locking
member 886 tending to disengage gears 890 from gears 884. However, when the
tip or
end 922 of elongated locking member 892 is engaged with the notch 926 of
recess 920 of
locking member 886, this engagement prevents rotational motion of locking
member 886
in a clockwise (released) direction, thereby locking gears 890 and 884 into
engagement
with one another and preventing height adjustment of the armrest.
[00146] To release the arm assembly for height adjustment of the armrest, a
user pulls
upwardly on pad 900 against a small leaf spring 899 (Fig. 50). The release
member 898
32
CA 02881887 2015-02-12
WO 2014/047255 PCT/US2013/060560
rotates about an axis 897 that extends in a fore-aft direction, and an inner
end of manual
release lever 898 pushes downwardly against bearing member 896/upper curved
portion
893 (Fig. 51) of elongated locking member 892. This generates a downward force
causing
elongated locking member 892 to rotate about pivot 894. This shifts end 922
(Fig. 50) of
elongated locking member 892 upwardly so it is adjacent to the shallow vertex
924 of
recess 920 of locking member 886. This shifting of locking member 892 releases
locking
member 886, such that locking member 886 rotates in a clockwise (release)
direction due
to the bias of leaf spring 902. This rotation causes gears 890 to disengage
from gears 884
to permit height adjustment of the arm rest assembly.
[00147] The arm rest assembly is also configured to prevent disengagement
of the height
adjustment member while a downward force F4 (Fig. 50) is being applied to the
arm rest
pad 804. Specifically, due to the 4-bar linkage formed by arm members 806,
808, arm
support structure 810, and arm rest assembly support member 812, downward
force F4
will tend to cause pivot point 820 to move towards pivot point 824. However,
the
elongated locking member 892 is generally disposed in a line between the
pivots 820 and
824, thereby preventing downward rotation of the 4-bar linkage. As noted
above,
downward force F4 causes teeth 890 to tightly engage teeth 884, securely
locking the
height of the armrest. If release lever 898 is actuated while downward force
F4 is being
applied to the armrest, the locking member 892 will move, and end 922 of
elongated
locking member 892 will disengage from notch 926 of recess 920 of locking
member 886.
However, the moment on locking member 886 causes teeth 890 and 884 to remain
engaged even if locking member 892 shifts to a release position. Thus, the
configuration
of the 4-bar linkage and locking member 886 and gear member 882 provides a
mechanism whereby the height adjustment of the arm rest cannot be performed if
a
downward force F4 is acting on the arm rest.
[00148] As best illustrated in Figs. 52 and 53, each arm rest assembly 804
is adjustably
supported from the associated arm support assembly 800 such that the arm rest
assembly 804 may be pivoted inwardly and outwardly about a pivot point 960
between
an in-line position M and pivoted positions N. Each arm rest assembly is also
linearly
adjustable with respect to the associated arm support assembly 800 between a
retracted
position 0 and an extended position P. Each arm rest assembly 804 (Fig. 53)
includes an
armrest housing assembly 962 integral with the arm rest assembly support
member 812
33
CA 02881887 2015-02-12
WO 2014/047255 PCT/US2013/060560
and defining an interior space 964. The arm rest assembly 804 also includes a
support
plate 966 having a planar body portion 968 and having a pair of mechanical
fastener
receiving apertures 969, and an upwardly extending pivot boss 970. A
rectangularly-
shaped slider housing 972 includes a planar portion 974 having an oval-shaped
aperture
976 extending therethrough, a pair of side walls 978 extending longitudinally
along and
perpendicularly from the planar portion 974, and a pair of end walls 981
extending
laterally across the ends of and perpendicularly from the planar portion 974.
The arm
rest assembly 804 further includes rotational and linear adjustment member 980
having
a planar body portion defining an upper surface 984 and a lower surface 986. A
centrally
located aperture 988 extends through the body portion 982 and pivotally
receives the
pivot boss 970 therein. The rotational and linear adjustment member 980
further
includes a pair of arcuately-shaped apertures 990 located at opposite ends
thereof and a
pair of laterally spaced and arcuately arranged sets of ribs 991 extending
upwardly from
the upper surface 984 and defining a plurality of detents 993 therebetween. A
rotational
selection member 994 includes a planar body portion 996 and a pair of flexibly
resilient
fingers 998 centrally located therein and each including a downwardly
extending
engagement portion 1000. Each arm rest assembly 804 further includes an arm
pad
substrate 1002 and an arm pad member 1004 over-molded onto the substrate 1002.
[00149] In assembly, the support plate 966 is positioned over the arm rest
housing
assembly 962, the slider housing 972 above the support plate 966 such that a
bottom
surface 1006 of the planar portion 974 frictionally abuts a top surface 1008
of the
support plate 966, the rotational and linear adjustment member 980 between the
side
walls 978 and end walls 980 of the slider housing 972 such that the bottom
surface 986
of the rotational and linear adjustment member frictionally engages the planar
portion
974 of the slider housing 972, and the rotational selection member 994 above
the
rotational and linear adjustment member 980. A pair of mechanical fasteners
such as
rivets 1010 extend through the apertures 999 of the rotational selection
member 994,
the arcuately-shaped apertures 990 of the rotational and linear adjustment
member 980,
and the apertures 969 of the support plate 966, and are threadably secured to
the arm
rest housing assembly 962, thereby securing the support plate 966, and the
rotational
and linear adjustment member 980 and the rotational selection member 994
against
linear movement with respect to the arm rest housing 962. The substrate 1002
and the
34
CA 02881887 2015-02-12
WO 2014/047255 PCT/US2013/060560
arm pad member 1004 are then secured to the slider housing 972. The above-
described
arrangement allows the slider housing 972, the substrate 1002 and the arm pad
member
1004 to slide in a linear direction such that the arm rest assembly 804 may be
adjusted
between the protracted position 0 and the extended position P. The rivets 1010
may be
adjusted so as to adjust the clamping force exerted on the slider housing 972
by the
support plate 966 and the rotational and linear adjustment member 980. The
substrate
1002 includes a centrally-located, upwardly extending raised portion 1020 and
a
corresponding downwardly disposed recess having a pair of longitudinally-
extending side
walls (not shown). Each side wall includes a plurality of ribs and detents
similar to the
ribs 991 and the detents 993 previously described. In operation, the pivot
boss 970
engages the detents of the recess as the arm pad 1004 is moved in the linear
direction,
thereby providing a haptic feedback to the user. In the illustrated example,
the pivot
boss 970 includes a slot 1022 that allows the end of the pivot boss 970 to
elastically
deform as the pivot boss 970 engages the detents, thereby reducing wear
thereto. The
arcuately-shaped apertures 990 of the rotational and linear adjustment member
980
allows the adjustment member 980 to pivot about the pivot boss 970 of the
support
plate 966, and the arm rest assembly 804 to be adjusted between the in-line
position M
and the angled positions N. In operation, the engagement portion 1000 of each
finger
998 of the rotational selection member selectively engages the detents 992
defined
between the ribs 991, thereby allowing the user to position the arm rest
assembly 804 in
a selected rotational position and providing haptic feedback to the user as
the arm rest
assembly 804 is rotationally adjusted.
[00150] A chair assembly embodiment is illustrated in a variety of views,
including a
perspective view (Fig. 55), a front elevational view (Fig. 56), a first side
elevational view
(Fig. 57), a second side elevational view (Fig. 58), a rear elevational view
(Fig. 59), a top
plan view (Fig. 60), and a bottom plan view (Fig. 61). An arm assembly
embodiment is
illustrated in a variety of views, including a perspective view (Fig. 62), a
front elevational
view (Fig. 63), a first side elevational view (Fig. 64), a second side
elevational view (Fig.
65), a rear elevational view (Fig. 66), a top plan view (Fig. 67), and a
bottom plan view
(Fig. 68).
[00151] In the foregoing description, it will be readily appreciated by
those skilled in the
art that alternative embodiments of the various components and elements of the
CA 02881887 2015-02-12
WO 2014/047255 PCT/US2013/060560
invention and modifications to the invention may be made without departing
when the
concept is disclosed. Such modifications are to be considered as included in
the following
claims, unless these claims by their language expressly state otherwise.
36
