Flexible armrest construction

Information

  • Patent Grant
  • 6343839
  • Patent Number
    6,343,839
  • Date Filed
    Friday, December 17, 1999
    24 years ago
  • Date Issued
    Tuesday, February 5, 2002
    22 years ago
Abstract
A component has a support with a stiff section and a flexible section. An incompressible resilient material, such as a gel, is supported on the flexible section. In one form, the component forms an armrest, with the support including upper and lower sections forming a loop. The upper section bridges between ends of the lower section and includes the flexible section, and a section of gel material is positioned on or molded onto the flexible section. In the armrest, the incompressible resilient material is sufficiently thick and resilient to comfortably support a person's forearm on the support yet further is sufficiently flowable and stretchable to at least partially move off a rib on the support and into the non-supporting areas when pressure is applied to the incompressible resilient material.
Description




BACKGROUND OF THE INVENTION




The present invention relates to flexible supports adapted with a section configured to evenly and comfortably support an object or body part placed on the support, and more particularly relates to a support including a flexible area and a gel-like or flowable material coupled to the flexible area.




Distribution of stress and the related aspect of comfort is an important quality in many products, especially furniture products such as seating. Traditionally, such furniture has included foam cushions to provide resilient support to users. However, foam cushions suffer from several limitations. Foam cushions compress and collapse in ways that do not necessarily optimally distribute stress, nor do they optimally provide the best support to a user. For example, in cushioned armrests, it is not uncommon for one area to fully compress, while another area does not. One reason may be because the area being compressed is limited by a perpendicular thickness of the foam cushion. For example, this can occur where the foam is formed into a thin sheet in order to avoid a “stuffed chair” look. Thus, areas of the cushion may compress to a point where they bottom-out, such that they cause high-pressure areas. Also, traditional cushions cannot flow laterally and “re-distribute” themselves to more uniformly support a weight rested thereon.




Foam cushions also have other problems Not only do they wear out, but their compression properties change over time. Also they may break down and disintegrate in a manner resulting in dust and fine debris. Further, many cushions are made from strong chemicals that are toxic or dangerous, such that they are potential environmental pollutants.




Aside from the above, it is desirable to provide adjustable furniture with an indicator providing a status of the adjustment. For example, this can be useful so that a user is able to quickly adjust a component to a known position of comfort. Further, many consumers want to see the “high tech” looking components that provide the adjustment.




Accordingly, an apparatus solving the aforementioned problems and having the aforementioned advantages is desired.




SUMMARY OF THE PRESENT INVENTION




In one aspect of the present invention, an armrest includes an armrest-supporting structure adapted for connection to a chair base. An armrest support includes at least one stiff section and a flexible section connected to the stiff section. The stiff section is located in a perimeter area of the armrest support and includes a mount secured to the armrest-supporting structure. A section of incompressible resilient material is coupled to and supported by the flexible section.




In another aspect of the present invention, an apparatus includes a support component having a stiff section with an attachment mount thereon and a flexible section extending from the stiff section. The flexible section includes strips of material constructed to flex relative to the stiff section. Incompressible resilient material is coupled to the flexible section for cooperative distribution of stress.




In another aspect of the present invention, a furniture component includes a support component having an apertured region with openings formed therein, and gel material positioned on the apertured region. The gel material has a memory but is configured to stretch and flow into the openings when pressure is applied to the gel material, such that the gel material distributes stress and provides a more uniform supporting action when an item is supported on the gel material and the support.




In another aspect of the present invention, an apparatus includes a support defining an elongated rib and non-supporting areas on opposing sides of the rib, the non-supporting areas being one of apertures or depressed areas. An incompressible resilient material is positioned on the support over the rib and the non-supporting areas. The incompressible resilient material is sufficiently thick and stiff to comfortably support a person's forearm on support and the rib, yet further is sufficiently flowable and stretchable to allow at least some of the incompressible resilient material to move off the rib and into the non-supporting areas when pressure is applied to the incompressible resilient material.




In another aspect of the present invention, a furniture component includes a support for supporting a human body part, the support defining first and second sections that are interconnected. Flowable material is coupled to the support and configured to flow from the first section toward the second section to more uniformly distribute stress when a human body part is placed on the support.




In another aspect, an apparatus includes an article, a component attached to the article, the component being shaped and configured to support a human body part, and a transparent material covering at least one side of the component. The clear material prevents physical access to the component but allows visual access to the component.




In another aspect, an apparatus includes an article, a structural component attached to the article, and an incompressible resilient material covering a portion of the structural component. The incompressible flexible material provides an outer surface shaped to be comfortably grasped and further provides a section capable of flowing and flexure to evenly distribute stress when the outer surface is grasped.




These and other aspects, advantages, and objects will be further understood and appreciated by those skilled in the art upon a close reading of the present specification, claims and appended drawings.











BRIEF DESCRIPTION OF DRAWINGS





FIG. 1

is a perspective view of a chair with armrests embodying the present invention;





FIG. 2

is an exploded perspective view of a mechanical adjuster mechanism of the armrest which permits lateral adjustment of the armrest construction;





FIGS. 3-5

are top, side, and front views of the armrest construction shown in

FIG. 1

, including the mechanical adjuster mechanism of

FIG. 2

, and a gel-covered armrest support;





FIGS. 6-9

are front, top, side, and bottom views of a bottom half support member of the armrest support shown in

FIG. 3

that connects to the mechanical adjuster mechanism of

FIG. 2

;





FIGS. 10-12

are top, side, and front views of a top half member of the armrest support shown in

FIG. 3

that bridges across and connects to opposing ends of the bottom half member of

FIG. 6

;





FIGS. 13-14

are cross-section views taken along lines XIII—XIII and XIV—XIV in

FIG. 10

;





FIGS. 15-18

are front, top, side, and bottom views of the internal support of the armrest shown in

FIG. 10

, including the perimeter-positioned stiff section and the interiorly-positioned flexible section;





FIG. 19

is an enlarged schematic cross section similar to

FIG. 13

but showing movement of the gel material hen stressed;





FIG. 20

is a side view of a first modified armrest similar to

FIG. 4

;





FIG. 21

is a side view of a second modified armrest similar to

FIG. 4

;





FIG. 22

is an exploded perspective view of a third modified armrest similar to

FIG. 4

;





FIG. 23

is an enlarged transverse cross-section of the armrest shown in

FIG. 22

; and





FIG. 24

is a perspective view of a fifth modified armrest similar to FIG.


4


.











DETAILED DESCRIPTION OF PREFERRED EMBODIMENT




A chair


30


(

FIG. 1

) includes armrest assemblies


31


embodying the present invention. The armrest assemblies


31


each include an armrest construction


32


(

FIG. 10

) adjustably mounted atop an under-seat-anchored armrest-supporting structure


41


by a mechanical adjuster mechanism


45


. The armrest construction


32


includes a loop-shaped armrest support


33


with a stiff section


34


(

FIG. 16

) and a flexible section


35


, and has an incompressible resilient material


36


(

FIGS. 13-14

) with a memory, such as a gel, molded onto the flexible section


35


. The incompressible resilient material


36


is sufficiently thick and resilient to comfortably support a person's forearm on the support, yet further is sufficiently flowable and stretchable to at least partially move off or through the flexible section


35


when significant pressure is applied to the incompressible resilient material


36


, such as when a seated user rests their forearms on, presses on, or grasps the armrests. (See FIG.


19


.). In this way, the armrest construction


32


provides exceptionally uniform and comfortable support to a seated person's arm. Further, the gel material


36


is clear or slightly translucent, such that a seated person can see through it. This advantageously allows a seated user to see where the armrest is laterally adjusted to (i.e. “width-wise), and further allows the seated user to see into the ribs


80


as they flex, which can be interesting and desirable to see to assure proper function.




The chair


30


(

FIG. 1

) includes a seat


38


and a back


39


operably mounted to a base


40


for coordinated movement upon recline of the back


39


. The under-seat support


41


is L-shaped and is fixed to a control housing on the base


40


. The under-seat support


41


includes a lateral leg


42


that extends from under the seat, and a vertically adjustable up leg


43


that extends above the seat


38


. A mounting plate


44


(

FIG. 2

) is secured to a top of the up leg


43


, and the armrest construction


32


is operably mounted to the mounting plate


44


by the mechanical adjuster mechanism


45


(FIG.


2


), as discussed below.




The description below of the mechanical adjuster mechanism


45


is sufficient for a person of ordinary skill in this art to understand the present invention. Nonetheless, a more detailed description and disclosure is provided in U.S. Pat. No. 5,971,484 (issued Oct. 26, 1999), and the entire contents of the patent '


484


are incorporated herein by reference.




The mounting plate


44


includes a pair of upwardly extending pivot pins


48


and


49


, and the mechanical adjuster mechanism


45


includes a pair of gear plates


46


and


47


with holes that rotatably engage the pivot pins


48


and


49


. The gear plates


46


and


47


include intermeshing teeth


50


and


51


, respectively, such that as one gear plate


46


is rotated, the other gear plate


47


simultaneously also rotates in an opposite direction. The gear plates


46


and


47


include up pivot pins


52


and


53


, respectively, that are located at outer ends of the gear plates


46


and


47


. An upwardly extending stabilizing finger


54


is located slightly inward of the up pivot pin


52


on gear plate


46


. A capture plate


56


is attached atop the gear plates


46


and


47


to the two main pivot pins


48


and


49


by screws


57


and


58


, such that the gear plates


46


and


47


are captured on the mounting plate


44


for rotational movement. A cover


59


is attached by screw


59


′ that extends through hole


59


″ in plate


44


.




The armrest support


33


(

FIG. 4

) has a flattened loop shape, and includes a lower section


60


and an upper section


61


. The lower section


60


(

FIG. 9

) includes an elongated horizontal body


62


having a relatively thin profile (FIG.


8


), and includes end sections


63


and


64


at each end of the body


62


. The bottom surface of the lower section


60


(

FIG. 8

) includes longitudinally-elongated rings of marginal material


65


and


66


that form a pair of longitudinally extending guide slots


67


and


68


near an outboard edge of the lower section


60


. A curvilinear stabilizer slot


69


(

FIG. 9

) is formed adjacent the guide slot


67


in the top surface and extends from the inboard edge of the lower section


60


toward an inner end of the guide slot


67


and then arcuately curves toward a middle of the lower section


60


as the stabilizer slot


69


extends to the outboard edge of the lower section


60


. The stabilizer slot


69


is configured to slidably engage the stabilizer finger


54


(

FIG. 2

) so as to cause the armrest support


33


to move laterally in a more controlled and stable manner when the armrest construction


32


is manually adjustingly slid inwardly or (outwardly). Specifically, the stabilizer finger


54


and slot


69


help reduce a tendency of the armrest construction


32


to rotate about a vertical axis and reduce a tendency to quickly slip outwardly. (Notably, as shown in U.S. Pat. No. 5,971,484, the armrest construction may also include structure permitting angular adjustment relative to the seat


38


.) The upper surfaces of the end sections


63


and


64


of the lower section


60


(

FIG. 7

) include reinforcement ribs


70


, attachment holes


71


and locator features


72


, such as a recess or ledge, that form a rigid mount.




The upper section


61


(

FIG. 18

) of the armrest support


33


includes an elongated body


74


, and end sections


75


and


76


. The end sections


75


and


76


are shaped to matingly engage the end sections


63


and


64


of the lower section


60


, with the body


74


of the upper section


61


bridging across and forming an arch between the end sections


63


and


64


of the lower section


60


. (See

FIG. 4.

) Screws (not specifically shown) extend upwardly through the attachment holes


71


(

FIGS. 7 and 9

) in the end sections


63


and


64


of the lower section


60


and threadably into the apertured bosses


77


in the end sections


75


and


76


. A protruding ridge


78


engages the locating feature


72


on the lower support


60


to align the upper and lower sections


60


and


61


during assembly and to add stability to the assembly.




The illustrated flexible section


35


(

FIG. 16

) is formed in a central area of the body


74


. The flexible section


35


includes several longitudinally extending ribs


80


. The ribs


80


are spaced laterally apart, and form a plurality of apertures


81


. The ribs


80


each have a cross section with a vertical dimension that is about four times their width. (See

FIG. 19.

) However, it is noted that the ribs


80


are supported by and stabilized by the gel material


36


molded around them, such that the ribs


80


flex substantially vertically when pressed. It is noted that the flexible section


35


can be made to be flexible by many different means, including “material” solutions and “dimensional/configuration” solutions, with only a few of these ways being shown in embodiments illustrated herein. For example, the material solutions include using bendable resilient polymers, spring steel, resilient reinforced composite materials, and the like. In the present embodiment, ribs


80


of the flexible section


35


are shaped to flex vertically, as well as the body


74


flexes relative to the ends


75


and


76


and the body


74


flexes relative to the lower section


60


.




The incompressible resilient material


36


(

FIGS. 13-14

) is substantially incompressible, but is stretchable and flexible with a memory. The illustrated gel is a proprietary urethane polymer, such as is described in U.S. Pat. No. 5,670,232 and 5,441,676 (to Bigolin). However, it is contemplated that the term incompressible resilient material as used herein includes other stretchable materials such as rubbers, silicones, and the like, and also that it includes other flowable materials encased in a bladder or balloon configuration.




The illustrated incompressible flexible material


36


(

FIG. 19

) is molded onto the upper support


61


, such that portions of the flexible material wrap around or encapsulate the ribs


80


, filling the openings between the ribs


80


. As molded, the incompressible flexible material


36


extends above the ribs


80


a distance sufficient to cause the flexible material


36


to evenly re-distribute stress when a seated person presses on the armrest construction


32


. This distance D


1


, as illustrated, is about equal to a width of the space between the ribs


80


, such as about ¼ inch. However, it is contemplated that the specific dimensions may vary greatly depending upon the properties of the gel, the dimensions of the ribs and the armrest itself, the expected forces to be exerted by a seated user, and the like. The amount of incompressible flexible material


36


that forms under the ribs


80


can be substantially thinner, such as about a dimension D


2


or about ⅛ inch. The purpose of this material is to hold together the material between ribs


80


and further to provide an aesthetic appearance under the upper section


61


. Some of the incompressible flexible material


36


(

FIG. 19

) flows off the ribs


80


and into the openings between the ribs


80


when a person rests their forearm on the armrest construction


32


, and some of it flows from between the ribs


80


and below the ribs


80


, when a seated user presses on the armrest construction


32


. It is noted that this “flowing” action produces a surprisingly and unexpectedly comfortable support where stress is well distributed. Preferably, the dimension D


1


is sufficiently thick so that a seated user does not feel the ribs


80


when pressing on the armrest.




In one form, the gel material


36


is sufficiently bonded together such that the gel material


36


does not need to be covered with a fabric. The gel material


36


is sticky, such that it is covered with a clear or translucent material, such as a urethane film or laminate. This provides a novel appearance when the armrest is not covered with a fabric since the gel material


36


is transparent and the ribs


80


can be seen. It is also contemplated that this can provide a utilitarian function, where a seated user can see into the armrest to view an item placed in the space


82


(

FIG. 4

) under the gel


36


. Also, a seated user can see structure through the armrest, such that the seated user can “read” a location of the armrest to determine the adjusted position of the armrest. Thus, the gel forms part of a position indicator for the adjustable component.




It is contemplated that the upper section


61


can be aesthetically covered with upholstery or skinned by ways known in the art. For example, the upper section


61


can be covered by wrapping an upholstery around the armrest, and securing it in place with adhesive, or by covering it with a urethane backedfabric. Also, the molds for forming the gel material can be pre-coated or post-coated with a skin-forming material.




Several additional embodiments are shown in

FIGS. 20-24

. Components and features of these additional embodiments that are identical or similar to the armrest construction


32


are identified by use of the same number, but with the addition of a letter, such as “A”, “B”, and “C”. This is done to reduce redundant discussion.




In a second embodiment embodying the present invention, an armrest construction


32


A (

FIG. 20

) includes an upper section


61


A includes a body


74


A and end sections


75


A and


76


A, with the body


74


A including ribs


80


A. The incompressible flexible material


36


A comprises two sheets


36


A′ and


36


A″ of gel material laid onto the ribs


80


A. The sheets


36


A′ and


36


A″ have different resilient properties. For example, the upper sheet


36


A′ could be a somewhat stiffer material than the lower sheet


36


A″, with the upper sheet


36


′ providing a stable support for a seated user's hand, and with the lower sheet


36


A″ being much more stretchy and fluid, such that the lower sheet


36


A″ flows to better distribute stress. It is contemplated that the sheets


36


A′ and


36


A″ could be die-cut from a sheet of gel material, or could be molded to their respective shapes.




The armrest construction


32


B (

FIG. 21

) includes a urethane foam


36


B′ in place of the upper sheet of gel


36


A′. The foam


36


B′ includes a varied thickness optimally suited for comfort and aesthetics. An upholstery


82


B is attached around the foam


36


B′, and tucked under the end sections


75


B and


76


B, before the upper section


61


B is attached to the lower section


60


. The body


74


B includes holes


83


B instead of longitudinally elongated openings between ribs. Notably, the body


74


B could be attached directly to the mounting plate


44


in a non-laterally adjustable arrangement, or could include structure permitting it to be operably attached to the gear plates


47


and


48


.





FIG. 22

is an exploded perspective view of a third modified armrest construction


32


C. Armrest construction


32


C is similar to the armrest construction


32


of

FIG. 4

, but the armrest support


33


C includes upper and lower sections


60


C and


61


C that are formed together as a looped shape. The upper section


61


C includes a pair of parallel edge ribs, with a relatively open area


84


B between the edge ribs. A separate flexible body


74


C is attached to the ribs


80


C, and includes inwardly extending leaf-spring-like fingers


85


C that form a longitudinal center slot


86


C and a plurality of opposing side slits


87


C. A stretchable fabric


88


C is laid on the body


74


C, and a flexible gel or foam material


36


C is placed on the stretchable fabric


88


C, and enclosed by the fabric


88


C. As shown in

FIG. 23

, the armrest construction


32


C provides a very comfortable support for a seated user's forearm, due to the flexure of the flexible material


36


C and also due to the flexure of the leaf-spring-like fingers


85


C. It is contemplated that the flexible material


36


C can be an incompressible flexible material, such as a polyurethane gel or rubber. It is further contemplated that the flexible material could be a liquid or gas, captured in a balloon-like arrangement by the stretchable fabric


88


C. Also, it is contemplated that in

FIG. 23

, a compressible flexible foam could be used.





FIG. 24

illustrates a perspective view of several armrest supports


33


D-


33


F that are not unlike the armrest support


33


C. The shape of the upper section


61


D,


61


E and


61


F are varied to provide particular flexural characteristics. For example, upper section


61


D provides several enlarged square openings in the body


74


D, while the upper section


61


E has a zipper-like-shaped opening in the body


74


E. The upper section


61


F has a plurality of longitudinally extending slits forming parallel leaf-spring-like strips in the body


74


F. Each of these arrangements provides a flexible section for supporting a gel or other incompressible resilient material


36


.




In the foregoing description, it will be readily appreciated by those skilled in the art that modifications may be made to the invention without departing from the concepts disclosed herein. Such modifications are to be considered as included in the following claims, unless these claims by their language expressly state otherwise.



Claims
  • 1. An armrest comprising:an armrest-supporting structure adapted for connection to a chair base; an armrest member supported by the armrest-supporting structure and including at least one stiff section and a flexible section connected to the stiff section, the stiff section being located in a perimeter area of the armrest member and including a mount secured to the armrest-supporting structure; and a section of incompressible resilient material coupled to and supported by the flexible section, the incompressible resilient material being molded onto the flexible section and covering the at least one stiff section; and wherein the flexible section includes ribs spaced apart to define apertures therebetween.
  • 2. The armrest defined in claim 1, wherein the at least one stiff section includes a pair of opposing end sections, and wherein the ribs are supported on each end by the opposing end sections.
  • 3. The armrest defined in claim 2, wherein the ribs include at least three ribs.
  • 4. An armrest comprising:an armrest-supporting structure adapted for connection to a chair base; an armrest member supported by the armrest-supporting structure and including at least one stiff section and a flexible section connected to the stiff section, the stiff section being located in a perimeter area of the armrest member and including a mount secured to the armrest-supporting structure; and a section of incompressible resilient material coupled to and supported by the flexible section, the flexible section including ribs spaced apart to define apertures therebetween; and wherein the section of incompressible resilient material characteristically stretches and flows when stressed, but includes memory such that the resilient material reforms to a predetermined shape when released, such that the resilient material stretches and flows into the apertures when pressed downward.
  • 5. The armrest defined in claim 4, wherein the incompressible resilient material is clear, such that movement of the flexible section can be seen.
  • 6. An armrest comprising:an armrest-supporting structure adapted for connection to a chair base, an armrest member supported by the armrest-supporting structure and including at least one stiff section and a flexible section connected to the stiff section, the stiff section being located in a perimeter area of the armrest member and including a mount secured to the armrest-supporting structure; and a section of incompressible resilient material coupled to and supported by the flexible section, the flexible section including ribs each having a fixed end supported by the at least one stiff section and a flexible end that is unsupported and moveable.
  • 7. The armrest defined in claim 6, wherein the section of incompressible resilient material characteristically stretches and flows when stressed, but includes memory such that the resilient material reforms to a predetermined shape when released, such that the resilient material stretches and flows into a new shape when pressed downward.
  • 8. The armrest defined in claim 6, wherein the section of incompressible resilient material includes a gel material.
  • 9. The armrest defined in claim 8, wherein the gel material includes a urethane material.
  • 10. An apparatus comprising:a support component having a stiff section with an attachment mount thereon and a flexible section extending from the stiff section, the flexible section including strips of material constructed to flex relative to the stiff section; and incompressible resilient material coupled to the flexible section for cooperative distribution of stress, and wherein a portion of the incompressible resilient material fits within the flexible section.
  • 11. The apparatus defined in claim 10, wherein the incompressible resilient material is clear.
  • 12. The apparatus defined in claim 10, wherein the strips include a free end constructed to flex relative to the stiff section.
  • 13. The apparatus defined in claim 10, wherein the incompressible resilient material covers an upper surface of the strips.
  • 14. The apparatus defined in claim 10, wherein the incompressible resilient material is molded onto the support.
  • 15. An apparatus comprising:an article; a component attached to the article, the component being shaped and configured to support a human body part; and a transparent material covering at least one side of the component and preventing physical access to the component but allowing visual access to the component wherein the transparent material comprises a gel.
  • 16. The apparatus defined in claim 15, wherein the article comprises a chair.
  • 17. The apparatus defined in claim 15, wherein the transparent material forms a flexible window.
  • 18. The apparatus defined in claim 15, wherein the component is adjustable, and the visual access provides feedback on an adjusted position of the component.
  • 19. The apparatus defined in claim 18, wherein the article comprises a chair, and the component includes a laterally adjustable armrest connected to the chair with a mechanical adjuster mechanism.
  • 20. The apparatus defined in claim 15, wherein the component is moveable, and the visual access provides feedback to the user during movement.
  • 21. The apparatus defined in claim 20, wherein the component includes a flexible section.
  • 22. The apparatus defined in claim 21, wherein the flexible section includes parallel flexible leaf-spring fingers.
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