U.S. patent application number 09/960754 was filed with the patent office on 2003-03-27 for aircraft seat with roller ball-assisted motion.
Invention is credited to Bachleitner, Ronald W., Brandt, Michael D., Szapa, Terry J..
Application Number | 20030057755 09/960754 |
Document ID | / |
Family ID | 25503575 |
Filed Date | 2003-03-27 |
United States Patent
Application |
20030057755 |
Kind Code |
A1 |
Brandt, Michael D. ; et
al. |
March 27, 2003 |
Aircraft seat with roller ball-assisted motion
Abstract
An adjustable chair is disclosed which can be used in aircraft,
motor homes, or the like. In an embodiment, the chair includes a
seat mounted on a base such that the weight of the seat rests on
roller ball assemblies disposed on a top surface of the base. The
roller ball assemblies advantageously reduce friction between the
seat and the base and improve translational and rotational
adjustment of the seat.
Inventors: |
Brandt, Michael D.;
(Marinette, WI) ; Bachleitner, Ronald W.;
(Peshtigo, WI) ; Szapa, Terry J.; (Menominee,
MI) |
Correspondence
Address: |
BLAKELY SOKOLOFF TAYLOR & ZAFMAN
12400 WILSHIRE BOULEVARD, SEVENTH FLOOR
LOS ANGELES
CA
90025
US
|
Family ID: |
25503575 |
Appl. No.: |
09/960754 |
Filed: |
September 21, 2001 |
Current U.S.
Class: |
297/344.24 |
Current CPC
Class: |
B60N 2/14 20130101 |
Class at
Publication: |
297/344.24 |
International
Class: |
A47C 001/02 |
Claims
We claim:
1. An adjustment mechanism for a chair to permit movement of the
chair, the adjustment mechanism comprising: a base having a top
plate with an opening formed therein; a seat structure having a
bottom member with an opening formed therein; roller buttons
interposed between the bottom of the seat structure and the top of
the top plate to permit movement of the seat structure relative to
the base, the roller buttons each comprising a roller ball disposed
within a housing such that a portion of the roller ball protrudes
from an opening in the housing to contact the seat structure; a
chair post coupled to the seat structure and extending downwardly
through the opening in the seat structure and the opening in the
top plate, the chair post being cylindrical and having a center
opening, the chair post being smaller in lateral dimension than the
opening of the top plate to permit movement of the chair post in
any direction; a shaft extending through the center opening in the
chair post; and a brake supported on a lower end of the shaft to
frictionally engage the top plate of the base to lock the seat
structure in an adjusted position, the brake being releasable to
permit adjustment of the chair.
2. The adjustment mechanism of claim 1, wherein the roller balls
comprise a low coefficient of friction material.
3. The adjustment mechanism of claim 1, wherein the brake
comprises: a lower brake plate; and an upper brake plate disposed
between the lower brake plate and the top plate, the upper brake
plate having a central opening which is smaller than an outer
dimension of the lower brake plate such that the upper brake plate
overlaps the lower brake plate, the upper brake plate having an
outer dimension which is greater than the opening in the top
plate.
4. The adjustment mechanism of claim 3, wherein the upper brake
plate has a rectangular shape.
5. The adjustment mechanism of claim 3, wherein the top plate
comprises: a plurality of runners.
6. The adjustment mechanism of claim 5, wherein the upper brake
plate is coupled to a lower surface of the top plate by the runners
to prevent rotation of the upper brake plate.
7. The adjustment mechanism of claim 1, further comprising: a cam
coupled to the chair post; and a cam follower coupled to the shaft
and positioned relative to the cam such that rotational movement of
the shaft results in axial movement of the shaft.
8. The adjustment mechanism of claim 7, wherein the cam comprises:
an upper cam surface, the cam and the cam follower positioned such
that the cam follower rides along the upper cam surface as the
shaft is rotated.
9. The adjustment mechanism of claim 8, wherein the cam follower
comprises: a pair of bearings mounted on opposite sides of the
shaft.
10. The adjustment mechanism of claim 8, wherein the upper cam
surface comprises: sloped sections; and sections with zero
slope.
11. The adjustment mechanism of claim 7, further comprises: a lever
extending radially from the shaft; a cable attached to the lever;
and a cable actuating mechanism connected to the cable to cause
rotation of the shaft in a first direction.
12. The adjustment mechanism of claim 11, further comprising: means
for normally biasing the shaft in a second direction of rotation
opposite to the first direction of rotation.
13. The adjustment mechanism of claim 12, wherein the means for
normally biasing the shaft comprises: an elastically deformable
member having a first end and a second end, the first end coupled
to the lever and the second end coupled to a bracket which is
coupled to the seat structure.
14. The adjustment mechanism of claim 3, wherein the lower brake
plate has an outer dimension which is smaller than the opening in
the top plate member.
15. An adjustment mechanism for a chair to permit movement of the
chair, the adjustment mechanism comprising: a base having a top
plate with an opening formed therein; a seat structure having a
bottom member with an opening formed therein; roller buttons
interposed between the bottom of the seat structure and the top of
the top plate to permit movement of the seat structure relative to
the base, the roller buttons each comprising a roller ball disposed
within a housing such that a portion of the roller ball protrudes
from an opening in the housing to contact the seat structure; a
chair post coupled to the seat structure and extending downwardly
through the opening in the seat structure and the opening in the
top plate, the chair post being cylindrical and having a center
opening, the chair post being smaller in lateral dimension than the
opening of the top plate to permit movement of the chair post in
any direction; a shaft extending through the center opening in the
chair post; and a brake supported on a lower end of the shaft to
frictionally engage the top plate of the base to lock the seat
structure in an adjusted position, the brake being releasable to
permit adjustment of the chair, the brake comprising a lower brake
plate, and a rectangular upper brake plate coupled by runners to a
lower surface of the top plate and disposed between the lower brake
plate and the top plate, the upper brake plate having a central
opening which is smaller than an outer dimension of the lower brake
plate such that the upper brake plate overlaps the lower brake
plate, the upper brake plate having an outer dimension which is
greater than the opening in the top plate.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to an adjustable chair for
aircraft, recreational vehicles and the like, and relates more
particularly to a chair having a single mechanism by means of which
lateral, longitudinal and swiveling movement can be effected.
BACKGROUND
[0002] Many airplanes, particularly corporate aircraft, have club
or lounge sections equipped with chairs capable of various
adjustments, including fore-and-aft, lateral, swiveling, and
reclining movement, or various combinations of these. At least
during takeoff and landing, the chair is normally locked in a fore
or aft facing position with the back in an upright position. When
the aircraft is not in a takeoff or landing mode, the chair can be
moved in the directions indicated, swiveled, or reclined to any
desired position of the occupant, within the travel limits of the
chair mechanism.
[0003] Furthermore, it has become customary to include adjustable
seats in recreational vehicles to permit the driver's and
passenger's seats to face forward when traveling and to face in an
arbitrary orientation when the vehicle is parked.
[0004] Previously, adjustable chairs of the type described normally
accommodated longitudinal and lateral travel by tracks, with the
actual movement being performed manually or by power assisted
means. The longitudinal and lateral movement has been typically
indexed by pins or friction locking, and the swiveling movement of
the chair has normally been indexed by means of pins. For example,
some chairs friction lock the seat to the base by biasing the seat
against fixed, solid buttons disposed on a top surface of a base.
However, this is not optimal.
[0005] Regardless of the type of mechanism employed for
accomplishing movement in the several directions indicated, prior
art adjustable chairs of this general type have been commonly
characterized as having a non-rigid feeling when locked, have been
relatively inconvenient to adjust by virtue of the locking pins
which require manipulation by the occupant, and by the relatively
limited positions of movement. Where a wide range of movement has
been provided for in prior art adjustable chairs, the mechanisms
permitting such adjustments have been uniformly characterized by
their relatively complicated and thus costly construction.
SUMMARY
[0006] Various embodiments disclosed herein provide an adjustable
chair with a single mechanism by means of which the chair can be
locked into position, or unlocked for horizontal or swiveling
movement. The mechanism includes a lever accessible to the occupant
adjacent the top and front of one of the arms of the chair, or any
other conveniently accessible position on the movable seat.
[0007] The mechanism permitting adjustment of the chair is further
characterized in that when locked, a rigid friction lock is
effected between the stationary supporting base for the chair and
the seat base. This rigidity is important not only in permitting
the chair to be absolutely maintained in its locked position, but
to essentially eliminate any movement between the seat base and the
stationary supporting base which might lead to impaired operation
of the adjustment mechanism.
[0008] One advantage of the adjustment mechanism is its simplified
construction and consequent low manufacturing costs. There are a
minimum of moving parts involved, thereby reducing maintenance
problems and costs. The relatively simple construction permits part
of the mechanism to be mounted within the seat portion of the
chair, thereby greatly reducing the components exposed at the
exterior of the chair. This permits the adjustment mechanism to be
readily adaptable to various chair configurations, and also to
constructions other than chairs where lateral and longitudinal
motion is desired to be provided for, but in a controlled
manner.
[0009] Another advantage is the infinite positions of movement into
which the seat can be adjusted. There are limits to lateral and
longitudinal sliding movement of the seat relative to the
supporting base, but within these limits, the seat can be easily
moved to an almost infinite number of positions and subsequently
locked due, in part, to the roller ball assemblies which reduce
friction between the seat and the base during adjustment. This
reduction of friction permits the seat to be moved to the most
comfortable position for the occupant.
[0010] A further advantage is that the adjustment mechanism is
easily operated. It provides a large holding force when engaged yet
requires only a small force for disengagement.
DESCRIPTION OF THE DRAWINGS
[0011] Various embodiments are illustrated by way of example and
not by way of limitation in the figures of the accompanying
drawings in which like references indicate similar elements. It
should be noted that references to "an," "one," or "various"
embodiments in this disclosure are not necessarily to the same
embodiment, and such references mean at least one.
[0012] FIG. 1 is a side elevational view, partially in vertical
section, of an embodiment showing the construction of the
adjustable chair.
[0013] FIG. 2 is a cross-sectional view of a roller ball assembly
according to one embodiment.
[0014] FIG. 3 is a partially exploded perspective view of the
underside of the base according to one embodiment.
[0015] FIG. 4 is a side elevational view, partially in vertical
section, showing the roller cam mechanism in the released
position.
[0016] FIG. 5 is a perspective view of the cam from the roller cam
mechanism.
[0017] FIG. 6 is a side elevational, partially in vertical section,
showing the roller cam mechanism in the clamped position with the
chair at an extreme limit of travel.
[0018] FIG. 7 is a top plan view of the roller cam mechanism in the
released position.
[0019] FIG. 8 is a perspective view of the base with roller ball
assemblies disposed on the top surface of the base top plate.
DETAILED DESCRIPTION
[0020] The various embodiments discussed herein overcome the
problems in the existing art described above by providing roller
ball assemblies which greatly reduce friction between the seat
structure and the base, which permits increased maneuverability of
the seat structure. In the following description, for the purposes
of explanation, numerous specific details are set forth in order to
provide a thorough understanding of the various embodiments. It
will be apparent, however, to one skilled in the art that the
various embodiments may be practiced without some of these specific
details. The following description and accompanying drawings
provide examples for the purposes of illustration. However, these
examples should not be construed in a limiting sense as they are
not intended to provide an exhaustive list of all possible
implementations.
[0021] Referring now to the application drawings, wherein the parts
are indicated by like reference numerals, and initially to FIG. 1,
adjustable chair 20 comprises seat structure 22 mounted on
supporting base 24 which includes top plate 26. As best seen in
FIG. 8, roller ball assemblies 28 are attached to the top of plate
26 to support the weight of seat structure 22 (not shown in FIG.
8). In the embodiment shown in FIG. 2, roller ball assemblies 28
each comprise roller ball 30 disposed in housing 32 with a
plurality of ball bearings 34 disposed between roller ball 30 and
housing 32. As can be seen, roller ball 30 is positioned in housing
32 such that a portion of roller ball 30 protrudes from an opening
in housing 32 to contact seat structure 22. In other embodiments,
ball bearings 34 are omitted so that roller ball 30 is in direct
contact with an inner wall of housing 32. Alternatively, ball
bearings 34 could be disposed in recesses in the inner wall of
housing 32 such that ball bearings 34 protrude from the recesses to
contact roller ball 30.
[0022] Roller balls 30 and bearings 34 are made of appropriate
materials having a low coefficient of friction. In various
embodiments, the material having a low coefficient of friction is a
synthetic material. In other embodiments, the material having a low
coefficient of friction is metal. Thus, roller balls 30 permit seat
structure 22 to slide freely on plate 26, since bottom surface 36
of seat structure 22 is metal. Bottom surface 36 contacts roller
balls 30 to facilitate the sliding action of seat structure 22.
[0023] For clarity, only the mechanical structure of chair 20 is
shown in the drawings. All upholstery and other non-mechanical
structure has been omitted for clarity. Seat arm rest 38 and seat
back 40 are shown schematically for context.
[0024] With particular reference to FIGS. 4-7, it will be seen that
the various embodiments also include a mechanism for locking seat
structure 22 onto top plate 26. This mechanism includes spindle 42
which receives self locking nut 44. Thrust bearing 46 is positioned
against the lower surface of lower brake plate 48 which is
vertically slidable on the outer surface of chair post 50. Chair
post 50 receives splines 52 of lower brake plate 48, which permit
vertical but not rotational movement of lower brake plate 48
relative to chair post 50.
[0025] Spindle 42 is vertically slidable inside of chair post 50
which is a hollow tubular structure. Accordingly, it can be seen
that if spindle 42 is moved upwardly, upward pressure is applied to
lower brake plate 48 through nut 44, and thrust bearing 46.
[0026] The upper surface of lower brake plate 48 has brake friction
material 54 bonded or otherwise applied to it. Material 54 can be
any conventional braking material. Upper brake plate 56 rests on
lower brake plate 48 and is movable relative to lower brake plate
48. Brake material 54 is also bonded or otherwise applied to the
upper and lower surface of upper brake plate 56 and to the lower
surface of top plate 26 as well. The upper surface of upper brake
plate 56 is positioned below top plate 26.
[0027] There is sufficient space between the hub of lower brake
plate 48 and the bottom of chair post 50 to permit spindle 42 to
move upwardly by a sufficient amount to cause a tight frictional
engagement between lower brake plate 48 and upper brake plate 56
and between upper brake plate 56 and the bottom surface of top
plate 26. In addition, there is a relatively large opening in top
plate 26 to permit a relatively large adjustment of seat structure
22 before chair post 50 abuts top plate 26. This opening, although
preferably rectangular, can be of any shape to permit sliding
adjustment in any direction. Also, chair 20 can be turned in any
angular orientation at any position of seat structure 22 relative
to the opening in top plate 26. Accordingly, a large degree of
translational and/or rotational adjustment is permitted.
[0028] As shown in FIG. 1, the outer diameter of lower brake plate
48 is less than the diameter of the opening in top plate 26. In an
embodiment shown in FIG. 3, upper brake plate 56 is rectangular to
span the width of the opening of top plate 26 and is fastened to
the lower surface of top plate 26 by runners 27 located along the
shorter sides of upper brake plate 56. Although not shown, upper
brake plate 56 has a lip which protrudes from the top side of upper
brake plate 56, and runners 27 engage the lip. In other
embodiments, runners 27 engage the entire thickness of upper brake
plate 56.
[0029] Fore and aft motion of the seat structure 22 is achieved by
moving upper brake plate 56 along with seat structure 22. Thus,
there will always be enough area of upper brake plate 56 to insure
that the opening in top plate 26 is bridged regardless of the
position of seat structure 22.
[0030] As shown in FIG. 4, seat structure 22 is located centrally
of the opening in top plate 26, and upper brake plate 56 fills the
gap between lower brake plate 48 and the lower surface of top plate
26. FIG. 6 shows seat structure 22 moved to an extreme limit of
travel where lower brake plate 48 and upper brake plate 56 are
positioned beneath top plate 26 with a portion of the opening not
supported, but, at a right angle to FIGS. 4 and 6, the opening is
spanned by upper brake plate 56. Thus, contact around the entire
circumference of the opening in top plate 26 is not required to
provide a stable locking engagement of seat structure 22 since
sufficient overlap between lower brake plate 48, upper brake plate
56 and top plate 26 will always be present to provide a secure
engagement at any position between those shown in FIGS. 4 and
6.
[0031] Again, referring to FIGS. 4 and 6, it will be seen that
chair post 50 is fixedly mounted to seat structure 22. An upper
annular flange 58 is formed integrally with chair post 50 and rests
on the top surface of the lower portion of seat structure 22. Chair
post 50 is attached by fasteners through upper annular flange 58 to
the top surface of the lower portion of seat structure 22.
[0032] Cam 62 is mounted on top of chair post 50 by the use of
bolts or the like. The shape of cam 62 is shown most clearly in
FIG. 5. Cam 62 is ring-shaped and has an upper sinusoidal helix
surface. Spindle 42 extends through chair post 50 and through the
center of cam 62. As best shown in FIG. 6, two roller bearings 64
are mounted on opposite sides of spindle 42 on a bolt or a shaft 66
whose central axis passes through spindle 42. Roller bearings 64
are held in position by nut 68 received on the threaded end of bolt
or shaft 66.
[0033] Roller bearings 64 and cam 62 form a roller cam release
mechanism which controls the vertical position of spindle 42. As
spindle 42 is rotated, roller bearings 64 ride on the upper surface
of cam 62, producing a non-linear vertical displacement of spindle
42. Accordingly, when roller bearings 64 ride to the highest point
on cam 62, upward pressure is applied through lower brake plate 48
and upper brake plate 56 to top plate 26, thereby locking seat
structure 22 in position. When roller bearings 64 are moved to the
lowest position on cam 62, the pressure from the brake plates is
released, and seat structure 22 is permitted to freely slide upon
roller ball assemblies 28, thereby permitting the occupant to
change the seat orientation to any translational or rotational
position desired. FIG. 4 shows the released position of the roller
cam mechanism where the seat is unlocked, and FIG. 1 shows the
locked position of the roller cam release mechanism.
[0034] Referring to FIGS. 1, 6 and 7, it will be seen that lever 70
is attached to the upper surface of spindle 42 by bolts, screws or
the like. Spring 72 has one end attached to lever 70 and a second
end attached to a spring bracket 74, which is mounted on seat
structure 22. Spring 72 keeps the roller cam release mechanism in
the locked position by pulling roller bearings 64 to the highest
point on cam 62. The slope of cam 62 is zero at locked position
giving neutral stability. The helix surface of cam 62 is also
undercut so that roller bearings 64 come up against neutral stops
at both ends of travel. Thus, spring 72 keeps roller bearings 64
against these neutral stops. First clevis 76 is also mounted on
lever 70 for connecting the cable of cable assembly 78 to lever 70.
The sheath of cable assembly 78 is connected through cable bracket
80 to seat structure 22. The opposite end of cable assembly 78 is
connected to cable bracket 82, and the cable is connected to hand
lever 84 through second clevis 86. Lever support 88 is mounted in a
position to insure accessibility of lever 84. As shown in FIG. 1,
lever support 88 can be mounted to arm structure 38 of seat
structure 22.
[0035] The roller cam mechanism is normally held in the locked
position by spring 72, which rotates lever 70 to the position shown
in FIGS. 1 and 7. To release the mechanism, hand lever 84 is moved
to the position shown in FIG. 4, which rotates lever 70. Lever 70
is attached to spindle 42, and rotation of lever 70 causes rotation
of spindle 42. Roller bearings 64 ride on cam 62. Rotation of
spindle 42 against spring 72 allows roller bearings 64 to drop to
the lowest position on cam 62. It will be noted that since cam 62
has a very small incline with a zero slope in the locked position,
the occupant of the seat is provided with a high mechanical
advantage. That is, only the force of spring 72 must be overcome in
order to release the roller cam mechanism. The amount of force
required to release the roller cam mechanism can be adjusted by
adjusting the length of lever 70.
[0036] With the roller cam release mechanism in the released
position, seat structure 22 can be moved laterally, longitudinally
and can be swiveled to any position desired. The lateral and
longitudinal movement of the seat structure is only limited by the
size and shape of the opening in top plate 26 and the size of lower
brake plate 48. When seat structure 22 is in the desired position,
hand lever 84 is released. Spring 72 rotates lever 70 to the
original position (shown in FIGS. 1 and 7), which also returns hand
lever 84 to the original position (shown in FIG. 1).
[0037] When mounting seat structure 22 on base 24, nut 44 is
adjusted until spring 72 can just overcome the forces applied by
the brake plates against the roller cam mechanism. The position of
nut 44 is maintained by a locking feature built into nut 44. Once
the mechanism has been rigged, the only necessary adjustment to
account for wear of brake material 54 is by adjustment of nut 44.
Also, by removing nut 44, seat structure 22 can be removed from
base 24.
[0038] Inclusion of upper brake plate 56 permits a greater amount
of adjustability with a smaller base 24. As can be seen in FIG. 1,
to provide the same amount of adjustability without using upper
brake plate 56, the size of base 24 would have to be increased to
accommodate a larger lower brake plate 48. Thus, upper brake plate
56 permits a smaller base 24 to be used.
[0039] It will thus be seen that the various embodiments disclose
an adjustment mechanism which is highly simplified in construction
and requires a minimum of force to be applied by the user. Very few
moving parts are involved and by release of the mechanism through
the operating lever, the chair seat can be moved to its adjusted
position and thereafter locked simply by releasing the operating
lever.
[0040] It will be understood that changes can be made in the system
without departing from the basic inventive concepts. For example,
the roller bearings can be rotated to release the brake plates by
means other than the cable illustrated. Other modifications to the
various embodiments would be readily apparent to one of ordinary
skill in the art. Accordingly, any such modifications and changes
would not depart from the scope of the invention as set forth in
the pending claims.
* * * * *