Cushion pad with enhanced conformability

Information

  • Patent Grant
  • 6219867
  • Patent Number
    6,219,867
  • Date Filed
    Thursday, April 8, 1999
    25 years ago
  • Date Issued
    Tuesday, April 24, 2001
    23 years ago
  • Inventors
  • Examiners
    • Trettel; Michael F.
    Agents
    • Hackler; Walter A.
Abstract
A wrist cushion includes an elastomer having the physical properties of flexibility and compressibility in the range of flexibilities and compressibilities of stable isomer block polymer gels, with the elastomer having a top surface and a cavity therein. A film is provided for encapsulating the elastomer with the film having physical properties of flexibility to enable uninhibited flexure and compression of the elastomer by a user. A liquid or thixotropic gel is provided and disposed in the elastomer cavity for enhancing lateral top surface movement of the elastomer upon shear force applied thereto by a user.
Description




The present invention generally relates to cushions and is more particularly directed to a cushion pad having enhanced conformability. Still more particularly the present invention is directed to a keyboard wrist pad having different zones of lateral movement and conformability.




Many cushions or pads for the support of a user are more suitable if the user does not have to slide along the pad in order to accommodate a change of position of a user's arm, leg or hand. That is, it is preferable that the pad accommodate such movement by lateral movement of the pad surface in contact with the user and or a change in conformability of the pad. This is particularly true in the case of keyboard wrist cushions or pads.




A number of cushions have been developed for use along the front edge of a keyboard, which is operated by a user's fingers or hand, such as in the case of a computer mouse.




Proper support is necessary, particularly in conjunction with repetitive computer keyboard operation, in order to prevent a number of medical problems which have been generally known as “carpal tunnel syndrome”. A great number of cushions have been developed which provide layers of cushioning materials, including gels. Many attempts have been made to enlarge the degree of movement of a supported wrist relative to the surface on which the wrist is supported. For example, see U.S. Pat. No. 5,713,544 which utilizes a pad having a layer of stable isomeric block polymer gel, in order to afford supporting a user's wrist and afford significant motion on the top surface of the pad, with the supported wrist relative to a bottom surface of the pad in a horizontal plane.




While greater lateral movement is afforded by a wrist rest assembly as set forth in the hereinabove referenced patent, the use of gels alone is limiting in the amount of lateral movement possible.




The present invention is directed to a cushion which provides wide lateral movement support, in addition to providing amusement for the user due to the internal structure of the cushion.




SUMMARY OF THE INVENTION




A cushion pad in accordance with the present invention generally includes an elastomer having the physical properties of flexibility and compressibility in the range of flexibilities and compressibilities of stable isomeric block polymer gels. The elastomer includes an exterior surface and a cavity therein along with film means for encapsulating the elastomer. The film means includes the physical properties of flexibilities to enable uninhibited flexure and compression of the elastomer by a user.




Importantly, means, disposed in the elastomer cavity, is provided for enhancing exterior surface movement of the elastomer upon shear force applied thereto by the user and for enhancing conformity of the pad upon compressive force applied thereto by the user.




In one embodiment of the present invention, the means for enhancing exterior surface movement and enhancing conformity of the pad comprises a thixotropic gel disposed in the elastomer cavity. The thixotropic property of the gel enables the gel to become fluid when force is applied and then becomes semisolid again.




The combination of the elastomer and thixotropic gel provides best conformity when the elastomer has a thickness, measured between the exterior surface and the cavity of at least about ½ inch to about 2 inches.




Further, the film means, elastomer and thixotropic gel may be transparent, thus enabling observance of a decorative object suspended within the thixotropic gel.




In another embodiment of the present invention, the means for enhancing exterior surface movement and enhancing conformity of the pad cushion comprises a liquid. In addition, the cushion pad in accordance with the present invention may include a polyurethane film having a thickness of between about 1 mil and about 5 mils. These limitations are important in providing the required physical properties of flexibility to enable uninhibited flexure and compression of the elastomer by a user as hereinabove noted.




Still more particularly, the elastomer has a thickness measured between the top surface and the cavity of at least about 1 inch. This thickness is important in establishing the resilient properties of the wrist cushion. With the thickness range as hereinabove cited, the wrist cushion retains the elasticity, resilience and compressibility of the elastomer material, despite the liquid filled cavity. Further, this thickness provides a means for enabling self-sealing in order to prevent the liquid from. leaking or reaching the exterior surface.




Accordingly the liquid, or thixotropic, filled cavity enables the wide lateral movement provided by the keyboard wrist cushion in accordance with the present invention.




In one embodiment of the present invention, air pockets disposed in the elastomer cavity provide a means for controlling, in combination with the elastomer, the overall compressibility of the wrist cushion. Because the air pockets are compressible, they can be used to modify the compressibility of the liquid, or thixotropic gel-filled cavity, of course, in combination with the elastomer itself.




Also, in accordance with the present invention, the film, elastomer and liquid, a thixotropic gel, may be transparent and the wrist cushion further comprises decorative objects suspended in the liquid within the cavity. The transparency enables the visual observation of the decorative objects by the user, particularly when used by the user as hereinabove noted.




The decorative objects can be moved within the cavity and liquid, a thixotropic gel, by compression forces applied to the cushion by the user. This movement is enhanced when used in combination with air pockets in the cavity.




Further, in accordance with the present invention, the elastomer includes a plurality of cavities therein, each of which may include a decorative object. In addition, at least one of the elastomeric cavities may be connected with another cavity for enabling movement of the decorative objects within the liquid from one cavity to another by compressive forces applied to the cushion by the user. In addition, multiple cavities enable general control of the resiliency of the cushion.




In yet another embodiment of the present invention, a keyboard wrist pad is provided which includes an elastomer having the physical properties of flexibility and compressibility in the range or flexibilities and compressibilities of stable elastomeric block polymer gels, the elastomer has a top surface and means defining a plurality of cavities therein, for controlling lateral top surface movement of different zones of said elastomer upon shear force applied thereto by a user.




Film means are provided for encapsulating said elastomer, said film means having physical properties of flexibility to enable uninhibited flexure and compression of said elastomer by the user.




Importantly, thixotropic or liquid means, disposed in each of the elastomer cavities is provided for enhancing the lateral top surface movement of said elastomer upon shear force applied thereto by the user and for enhancing conformity of the pad upon compressive force applied thereto by the user.











BRIEF DESCRIPTION OF THE DRAWINGS




The present invention may be more clearly understood with reference to the following detailed description in conjunction with the appended drawings, of which:





FIG. 1

is a perspective view of the present invention;





FIG. 2

is a cross sectional view of the cushion shown in

FIG. 1

taken along the line


2





2


showing in cross section any elastomer encapsulated by a film, with the elastomer having a cavity therein, which is liquid filled; and





FIG. 3

is a cross sectional view of the cushion shown in

FIG. 1

taken along the line


3





3


showing a plurality of interconnected separate elastomer cavities along with a decorative object which may be moved from one cavity to another, as shown in dash line, by compressive forces from a user's wrist.











DETAILED DESCRIPTION




With reference to

FIG. 1

, there is shown a cushion pad


10


in accordance with the present invention, which, as is more particularly shown in

FIG. 2

, includes an elastomer


14


and a film


16


which provides a means for encapsulating the elastomer.




In a generally elongate configuration, as shown in the Figures, the pad is suitable for a keyboard wrist pad. It should be appreciated, however, that other pad shapes (not shown) may be utilized depending on the intended use of the pad.




A cavity


20


formed within the elastomer


14


, may include either a thixotropic gel or a liquid which provides a means for enhancing lateral exterior or top surface


26


movement (as indicated by arrows


30


,


32


) upon shear force applied to the surface


26


by a user and enhancing conformity of the pad


10


upon compressive force applied to the surface


26


by the user.




Encapsulation of the elastomer is important for providing a desired textured surface as well as preventing any leakage of plasticizing oil which may be utilized in the elastomer.




The elastomer


14


may be of any suitable type such as, for example, a stable isomeric block polymer gel similar to the gel described in U.S. Pat. No. 3,676,387. This patent is incorporated herewith in its entirety for the purpose of describing a suitable type of gel for incorporation into the present invention.




Generally, the gels are of polymer-oil combinations. Specifically, the elastomer


14


has the physical properties of flexibility and compressibility in the range of flexibilities and compressibilities of the stable elastomer block polymer gels such as set forth in U.S. Pat. No. 3,676,387.




With reference to

FIGS. 2 and 3

, the transparent film


16


may be of urethane, or polyurethane film, which encapsulates the transparent elastomer


14


. The film


16


thickness as hereinabove noted is preferably between about 1 mil and about 5 mils in order to encapsulate the elastomer


14


, yet have a resiliency which enables free gel-like movement, or compression, or depression of the elastomer


14


by a user's wrist


36


. See FIG.


3


.




That is, the film


16


has physical properties of flexibility because of its thickness to enable uninhibited flexure and compression of the elastomer


14


by the user


36


. Film


16


thickness beyond this range has not been found to be effective in maintaining the gel-like property of the elastomer


14


while providing encapsulation of the elastomer


14


.




As hereinabove noted, the elastomer


14


includes a cavity


20


which is filled with thixotropic gel, a colloid, or a liquid


22


, preferably an oil, such as, for example, a mineral oil. The colloid may be a suspension of solids in liquid or an emulsion of two liquids which have properties suitable for enhancing conformity of the pad


10


upon compressive force applied thereto by the user.




The thixotropic gel may be any suitable thixotropic gel such as, for example, described in U.S. Pat. No. 4,200,561, which is incorporated herewith in it's entirety for the purpose of describing suitable thixotropic gels. The gel or liquid


22


filled cavity


20


enhances the lateral top surface movement indicated by the arrows


30


,


32


by a shear force in the direction of arrows


30


,


32


applied to the top surface


26


of the cushion


10


. A thixotropic gel provides unique properties for the pad


10


because of its being a semisolid colloid when undisturbed, but flowing readily when subjected to stress.




An elastomer, a thickness indicated by the arrow


40


, between the cavity


20


and the top surface


26


, is greater than about ½ inch to about 2 inches in order to maintain the flexibility and compressibility of the cushion


14


. Utilizing an elastomer having a width of about 3 to about 5 inches, a user's wrist can be laterally moved up to about 1 to 2 inches without slipping from the top surface


26


.




In addition, an elastomer of this thickness provides a self-sealing feature. If the elastomer is punctured or ruptured in some manner, its resiliency causes closure of the puncture or rupture in order to prevent leakage of the liquid


22


or seepage of the thixotropic gel.




The compressibility of the cushion may be further enhanced by providing air pockets


42


within the cavity


20


. Because these air pockets are compressible, the overall feel compressibility and flexure properties of the cushion


10


may be modified. These air pockets take up between about 25% and about 75% of the total volume of the cavity


20


. A desirable air pocket volume is about 50% of the total volume.




In order to provide zonal control of cushion


10


resiliency, the cushion


10


may include multiple cavities


20


,


44


,


46


as shown in

FIG. 3

, corresponding air pockets


50


,


52


being present in the cavities


44


,


46


and separated from one another by constricted, narrowing or isthmus areas


56


,


58


. By incorporation of different size air pockets


42


,


50


,


52


, zonal compressibility properties may be provided across the cushion


10


.




Further, the control of lateral movement of the cushion


10


surface


26


is controlled by the size of the various cavities


42


,


50


,


52


. That is, a center portion


64


may have greater lateral motion than side portions, or zones,


66


,


68


. This is important in providing a controlled lateral wrist movement afforded by the cushion


10


when disposed in front of the keyboard, not shown, to facilitate the striking of certain keys (not shown). Such control may also be afforded by utilizing different liquids or thixotropic gels in the various cavities


42


,


50


,


52


.




In accordance with the present invention, if the cavities are not interconnected liquid may be used in one or more of the cavities


42


,


50


,


52


along with the thixotropic gel in others of the cavities


42


,


50


,


52


.




Yet another feature of the present invention is shown and illustrated in

FIGS. 2 and 3

. By utilizing a transparent urethane film


16


, elastomer


14


and liquid


22


, the viewing of the decorative object


70


disposed and suspended within the liquid


22


can be realized.




Movement of the decorative object


70


within the liquid


20


or, for that matter, within the liquid


72


,


74


disposed within the cavities


44


,


46


, respectively, through the isthmus


56


,


58


, can be actualized by compressive forces supplied to the cushion top surface


26


, at the center zone


64


, or side zone


66


,


68


by the wrist


36


.




Thus, movement of the user's wrist


36


, when in an operative compressive relationship with the cushion


10


and providing shear forces thereon to cause lateral movement, also causes a movement of a decorative object


70


within the cavity


20


or between the cavities


20


,


44


,


46


, with such movement being further enhanced by the air pockets


42


,


50


,


52


disposed respectively in the cavities


20


,


44


,


46


. This feature is also available with the proper selection of the thixotropic gel.




Alternatively, the liquid or gel


22


may be semi-translucent with opaque swirls or the like therein in order to provide a different visual effect.




The process of forming the cushion


10


is through the process set forth in U.S. Pat. No. 5,679,193 entitled, METHOD OF MANUFACTURING A GEL CUSHION; U.S. Pat. No. 5,756,184 entitled, GEL CUSHION; and in U.S. patent application Ser. No. 08/856,775 filed May 15, 1997 entitled, CUSHION MANUFACTURING METHOD. Both of these referenced patents and the application are incorporated herewith in their entirety by this reference thereto, for illustrating the manner in which the gel cushion in accordance with the present invention may be manufactured.




Although there has been hereinabove described a keyboard wrist cushion in accordance with the present invention, for the purpose of illustrating the manner in which the invention may be used to advantage, it will be appreciated that the invention is not limited thereto. Accordingly, any and all modifications, variations or equivalent arrangements which may occur to those skilled in the art should be considered to be within the scope of the invention as defined in the appended claims.



Claims
  • 1. A cushion pad comprising:an elastomer having the physical properties of flexibility and compressibility in the range of flexibilities and compressibilities of stable elastomeric block polymer gels, said elastomer having an exterior surface and a cavity therein; a film for encapsulating said elastomer, said film having physical properties of flexibility to enable uninhibited flexure and compression of said elastomer by a user; and a thixotropic gel, disposed in the elastomer cavity, for enhancing exterior surface movement of said elastomer upon shear force applied thereto by the user and for enhancing conformity of the pad upon compressive force applied thereto by the user.
  • 2. The pad according to claim 1 wherein said elastomer has a thickness, measured between the about exterior surface and the cavity, is between about ½ inch and about 2 inches.
  • 3. The pad according to claim 1 wherein said film, elastomer and thixotropic gel are transparent.
  • 4. The pad according to claim 3 further comprising decorative objects suspended in said thixotropic gel and visible through said film, elastomer and thixotropic gel.
  • 5. The pad according to claim 1 wherein said elastomer comprises a plurality of cavities each having a thixotropic gel disposed therein.
  • 6. A cushion pad comprising:an elastomer having the physical properties of flexibility and compressibility in the range of flexibilities and compressibilities of stable elastomeric block polymer gels, said elastomer having an exterior surface and a cavity therein; a film for encapsulating said elastomer, said film having physical properties of flexibility to enable uninhibited flexure and compression of said elastomer by a user; and means, disposed in the elastomer cavity for enhancing exterior surface movement and enhancing conformity of the pad, said means comprising a liquid disposed in the elastomer cavity.
  • 7. The pad according to claim 6 further comprising air pockets, disposed in the elastomer cavity, for controlling, in combination with said elastomer, overall conformability and compressibility of said pad.
  • 8. The pad according to claim 7 wherein the elastomer thickness is between about ½ inch and about 2 inches.
  • 9. The pad according to claim 6 further comprising air pocket means disposed in the elastomer cavity, for controlling, in combination with said elastomer, an overall conformability and compressibility of said pad.
  • 10. The pad according to claim 6 wherein said film, elastomer and liquid are transparent and the cushion further comprises decorative objects suspended in said liquid.
  • 11. The pad according to claim 10 further comprising air pockets, disposed in the elastomer cavity, for enabling movement of said decorative objects within said liquid by compression forces applied to the pad by the user.
  • 12. A keyboard wrist pad comprising:an elastomer having the physical properties of flexibility and compressibility in the range of flexibilities and compressibilities of stable elastomeric block polymer gels, said elastomer having a top surface and a plurality of cavities therein for controlling lateral top surface movement of different zones of said elastomer upon shear force applied thereto by a user; a liquid, disposed in each of the elastomer cavities for enhancing the lateral top surface movement of said elastomer upon shear force applied thereto by the user and for enhancing conformity of the pad upon compressive force applied thereto by the user.
  • 13. The pad according to claim 12 wherein said film comprises a polyurethane film having a thickness of between about 1 mil and about 5 mils.
  • 14. The pad according to claim 13 wherein said elastomer has a thickness, measured between the top surface and the cavity of between about ½ inch and about 2 inches.
  • 15. The pad according to claim 14 further comprising air pockets, disposed in at least one of the elastomer cavities, for controlling, in combination with said elastomer, overall conformability and compressibility of said pad.
  • 16. The pad according to claim 15 wherein said film, elastomer and liquid are transparent and the cushion further comprises decorative objects suspended in said liquid of at least one of the cavities.
  • 17. The pad according to claim 16 further comprising air pockets, disposed in the elastomer cavity containing the decorative objects, for enabling movement of said decorative objects within said liquid by compressing forces applied to the cushion by the user.
  • 18. The pad according to claim 12 wherein said film, elastomer and liquid are transparent, the cavities are interconnected and the cushion further comprises decorative objects, suspended in said liquid.
  • 19. The pad according to claim 18 further comprising air pocket pockets disposed in the cavities for enabling movement of said decorative objects between the cavities by compression forces applied to the pad by the user.
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Number Name Date Kind
4200561 Chang Apr 1980
4924634 Saloff et al. May 1990
5121962 Weber et al. Jun 1992
5445858 Nwoko Aug 1995
5679193 Yates Oct 1997
5713544 Wolf et al. Feb 1998
5756184 Yates May 1998
5826841 Lavore Oct 1998
5980143 Bayer et al. Nov 1999
6050964 Yates Apr 2000