Armchair with variable position

Information

  • Patent Grant
  • 6820935
  • Patent Number
    6,820,935
  • Date Filed
    Wednesday, April 9, 2003
    21 years ago
  • Date Issued
    Tuesday, November 23, 2004
    20 years ago
  • Inventors
  • Examiners
    • White; Rodney B
    Agents
    • Dykema Gossett PLLC
Abstract
The invention discloses an armchair (1) with variable position comprising a support structure (2) having a post (3) defining a first vertical axis (Z), a first frame (8) comprising a first pivot (9) defining a second horizontal axis (X), a second frame (12) swinging at one end (11) around the first pivot (9), thrust means (14) connected to the first frame (8) and acting against the end (11) of frame (12) to resist its swinging movement around the axis (X), a seat (10) supported by the first frame (8) and a backrest (13) supported by the second frame (12). The seat (10) is connected at least to the first frame (8) through first elastic means (15) adapted to allow a rotary translatory motion to the seat (10). The backrest (13) is connected to the second frame (12) through second elastic means (22) to allow a further rotary translatory motion.
Description




The present invention relates to an armchair adapted to take variable positions due to the thrust action exerted on the seat and the backrest by the sitting person so as to follow the movements of said person.




Several types of chairs or armchairs are available on the market, in which the variable position is obtained by the static adjustments provided, as well as by the dynamic features of the peculiar elastic deformability of the seat or back structure or elastic means interposed between the structural elements of the chair.




Pressure exerted by the sitting person on the seat or the backrest or on both elements at the same time, modifies the chair position adjusting the position as far as possible to the new sitting position.




However, more particularly in the frequent changes from the sitting position crouching forward to the stretched position backward, the user feel the resistance of the chair structure to follow said movements. More particularly the user feels the annoying scraping against the surface of the seat or the backrest with consequent trouble and inconvenience.




Moreover the most natural positions the user aims to take, are often constrained only to the intrinsic elastic deformability of the seat and backrest padding without any actual possibility of adjustment when the user is sitting.




In order to remove said drawbacks, the international application of the same inventor published as document WO00/18274, discloses a chair with variable position allowing the sitting position to change from a sitting position crouching forward to another sitting position generally stretched backward. This is obtained merely exerting a thrust on the seat that changes its position relative to the chair support without scraping of the person sitting on the seat surface. Moreover the amount of position variation may be modified by acting on proper adjustment members.




The chair with variable position disclosed in said document has however the drawback to allow only straight seat movements back and forth along a plane. Another drawback consists in that seat and backrest are connected to each other, leading to an undesired constraint because a movement of the seat causes anyway a certain movement of the backrest.




In other words the movements of seat and backrest are interdependent and cannot be separated.




The U.S. Pat. No. 6,116,687 discloses a functional chair having a seat part connected to the head part of the pedestal via a joint comprising an elastomeric material which permits the tilting of the seat part.




The U.S. Pat. No. 4,640,548 discloses an adjustable chair having three horizontal transvers axes connecting the seat and the column, the column and the curved supporting bar and the curved supporting bar and the seat, respectively.




At least one axis permits both the swiveling motion and the relative shift.




The U.S. Pat. No. 4,986,601 discloses a tilting mechanism for a seat able to tilt the seat both forward and backward. The supporting member on which the backrest is mounted is connected with this seat plate so that the supporting member acts interlockingly with that one of the seat plate.




The present invention aims at overcoming this limitation.




More particularly the object of the present invention is to provide a chair or armchair with variable position allowing a greater number of degrees of freedom in the movements of both the seat and the backrest.




Another object is to provide a chair in which seat and backrest can be moved independently from one another when desired.




A last but not least object is to provide a chair allowing movements of both seat and backrest forward, backward, laterally and even on planes other then the original rest ones.




Said objects are attained by an armchair with variable position the main features of which are according to claim


1


.




According to a preferred embodiment the support structure consists of a plurality of radially arranged bearing elements connected to the lower end of the support post.




Advantageously in view of the combination of the mutual sliding motion between seat and backrest and of the degree of freedom given by the elastic means to both seat and backrest, the rotary translatory movement of the seat is generated also on other planes than the initial resting plane and a movement of the backrest which is substantially independent from the movement of the seat, so that the user's back is always leaning on the backrest even when changing his rest position on the seat, for instance in case of changing crossing of the legs.











Said objects will be more apparent by reading the following description of preferred embodiments of the chair of the invention with reference to the accompanying sheets of drawings in which:





FIG. 1

is an isometric view of the armchair of the invention;





FIG. 2

is an isometric view of a portion of the armchair of

FIG. 1

without the seat;





FIG. 3

is an isometric view of another portion of the armchair of

FIG. 1

without the backrest;





FIG. 4

is an isometric view of a device acting on the backrest of the armchair of

FIG. 1

;





FIG. 5

is a longitudinal exploded sectional view of the device of

FIG. 4

;





FIG. 6

is a longitudinal sectional view of another element of the armchair of

FIG. 1

;





FIG. 7

is an isometric view of an armrest of the armchair of

FIG. 1

;





FIG. 8

is a front view of the armrest of

FIG. 7

;





FIG. 9

is an isometric view of an elastic means of the armchair of

FIG. 1

; and





FIG. 10

is an exploded, partially sectional side view of the elastic means of FIG.


9


.











The armchair of the present invention is shown in

FIG. 1

where it is generally indicated with reference numeral


1


.




The armchair consists of a support structure generally indicated with numeral


2


comprising a post


3


defining a first vertical longitudinal axis Z. In this embodiment, the post


3


is the rod of a pneumatic cylinder


3




a


adapted to adjust the height of the seat of the armchair. The upper end


4


of cylinder


3




a


is connected to a plurality of spokes


5


resting on the ground, radially arranged and provided with wheels


6


adapted to allow the chair


1


to slide on the floor.




The upper end


7


of the post


3


as shown in

FIG. 2

is connected to a first frame generally indicated with numeral


8


, of a generally quadrilateral form. Said frame is provided with a first pivot


9


defining a second horizontal longitudinal axis X orthogonal to the vertical axis Z supporting a seat


10


.




The lower end


11


of a second frame


12


is pivoted to the first pivot


9


and has two facing and spaced arms


12




a


,


12




b


as shown in detail in FIG.


3


and supporting the backrest


13


of the arm chair of the invention.




The static balance of the second frame


12


is warranted by thrust means generally indicated with numeral


14


, connected to the first frame


8


and acting against the end


11


of the second frame


12


so as to resist the swinging movement around the longitudinal axis X to which said second frame would be compelled under the thrust of the user's back.




The invention provides for the connection of the seat


10


to the first frame


8


through first elastic means generally indicated with numeral


15


, arranged under the front part of the seat and adapted to allow a rotary translatory motion in combination with other rear bearing elements that will be described below (on a generally spherical surface π defined by the points where the seat


10


rests on the elastic means


15


and on the rear bearing elements).




Each first elastic means


15


comprising an elastic yielding body


15




a


that in this embodiment is a bellows with a shape comparable to the spherical one as shown in detail in

FIGS. 9 and 10

. Said elastic means is associated to the first frame


8


and to the seat


10


through fastening means


61


consisting of a couple of screws


62


,


63


engaged in corresponding nuts made in a couple of discs


64


integral with said body


15




a.






It is clear that in different embodiments the fastening means may consist of other joining elements with or without interposition of washers instead of screws and nuts, and the elastic body


15




a


preferably made of an elastomeric material, may take a prismatic shape.




The seat


10


as shown in

FIG. 1

, at the rear part is resting on two sliding tubular members


16


,


17


spaced from one another through a spacing element


18


and idly coupled to a second pivot


19


connected to the second frame


12


.




The tubular members


16


,


17


have also their outer surface conjugated to the lower generally spherical surface of seat


10


resting on the members


16


,


17


.




It is important to note that when the seat


10


is moving also transversally under the thrust of the sitting person changing his position the tubular members


16


and


17


bearing the rear part of the seat are rotating in the opposite direction even at different angles. This movement combined with the extreme versatility of the front bellows bearings


15


, allows the seat to take the most diversified positions following the movements of the sitting person even along planes which are not necessarily horizontal.




As to the backrest


13


, it is connected to the second frame


12


through second elastic means fixed to the arms


12




a


,


12




b


and generally indicated with


22


, adapted to allow a free rotary translatory motion on a generally plain surface α defined by the points where the backrest


13


is leaning on said second elastic means


22


.




Said second elastic means


22


comprise an upper part consisting of a couple of cylindrical bodies


23


,


24


made of elastomeric material and a lower part consisting of a pressure element


25


slidingly and rotatably coupled to a third support pivot


27


connected to the second horizontal frame


12


. It is to be noted that nothing prevents that the elastic bodies


23


,


24


are also bellows elements like the elements of the seat indicated with numeral


15


.




The pressure element


25


shown in detail in

FIGS. 4 and 5

, comprises a first tubular member


26


internally threaded and provided with a transversal through hole


26




b


adapted to slidingly receive the pivot


27


. A second tubular element


28


externally threaded and provided with an actuation knob


28




a


, can be screwed to the first element so as to change the length and therefore the thrust exerted by the elastic element


28




b


connected to the second element


28


.




The user acting on the knob


28




a


thus can vary at will the length of the pressure element


25


so as to obtain a variation of the rest inclination of the backrest


10


relative to the vertical axis Z, until he finds the most comfortable position.




As to the thrust means


14


shown in

FIG. 6

, they consist of a stem


40


having a first end provided with a spherical head


41


and a second end


43


slidingly coupled in a guide hole


44


made in a sleeve


45


.




The spherical head


41


is coupled to a conjugated seat made in a lever arm


42


belonging to the end


11


of the second frame


12


.




The sleeve


45


is provided with an actuation knob


45




a


and has a threaded outer surface coupled to a corresponding internally threaded ring


50


connected to a fork


51


.




The ring


50


is fixed to the fork


51


through a couple of coupling pins


52


allowing its free rotation around the axis defined by said pins.




The stem


40


is also provided near its first end, with a compression disc


46


resisting the end


47


of a helical spring


48


coaxially coupled to said stem


40


and having its second end


49


opposed by the sleeve


45


.




The user acting on the knob


45




a


screws or unscrews the sleeve


45


compressing or decompressing the spring


46


so as to vary the thrust exerted on the end


11


of the second frame


12


which is made more or less rigid.




The adjustment of the thrust is a function of the weight of the person sitting on the armchair so that the thrust means


14


is to be adjusted only once and then kept at the constant adjustment.




Still according to the invention the armchair


1


comprises also a couple of armrests


30


,


31


shown in

FIGS. 7 and 8

. Each armrest comprises a third frame


32


anchored to the first frame


8


and supporting a guide member


33


defining a third longitudinal axis Y orthogonal to the longitudinal axis X, the resting portions


34


,


35


of the armrests


30


and


31


respectively being slidingly and rotatably coupled to said guide element. This allows the portions


24


,


25


to be tilted by a rotation of 90° degrees clockwise or counterclockwise around said longitudinal axis Y respectively.




With the armchair according to the invention when the sitting person exerts a thrust against the seat


10


or the backrest or both, the pressure force is discharged on the elastic means


15


of the seat and those


22


of the backrest so that the generated force is resolved along the axes X and Z as defined hereinbefore.




Therefore the seat


10


is moved according to a motion resulting from the combination of the movements due to the forces acting along the axes X and Z, however remaining on the spherical surface n on which the seat is lying when in the rest condition.




As to the backrest


13


, it may swing around the axis X while the thrust element


14


opposes to said movement a force equal to a quantity selected by the user acting on the actuation means provided for said thrust element.




In connection with said swinging motion the backrest


13


may also have although not necessarily, a rotary translatory motion along the plane α defined by the second elastic means.




In this connection it is to be noted that the seat and the backrest are free to move along their own planes π and α respectively, either independently or in a related way according to the nature and complexity of the movements of the person when sitting on the armchair.




The user may also change the height of the seat by acting on the support sleeve


3


and selecting the position of the backrest as previously described, acting both on the thrust means and the pressure element.




It is clear that the chair of the invention herein described and illustrated, may be constructed with any shape and dimensions and may also have different constructional versions as to the elastic means and the connection elements.




Although the invention was described by making reference to the FIGs. shown in the accompanying sheets of drawings, it may undergo several modifications and constructional variations, all falling however in the scope of the invention set forth in the appended claims.



Claims
  • 1. An armchair with variable position comprising:a support structure resting on the ground and having a post defining a first generally vertical longitudinal axis; a first frame supported by said post comprising a first pivot defining a second generally horizontal longitudinal axis orthogonal to said first longitudinal axis; a second frame swinging at one end around said first pivot; thrust means connected to said first frame and acting against said end of said second frame to resist the swinging movement of said second frame around said second longitudinal axis; an elastic bellows secured to the frame and the seat; a seat supported by said first frame and connected to it through said bellows; a backrest supported by said second frame and connected to it through second elastic means; wherein said seat is connected to said first frame through first elastic means and through rear bearing elements, said first elastic means and said rear bearing elements allowing a rotary translatory motion around a generally spherical surface (π) said rear bearing elements being able to revolve in two opposite directions during the transversal movement of said seat, and wherein said backrest is connected to said second frame through second elastic means allowing a further rotary translatory movement of said backrest.
  • 2. The armchair according to claim 1, wherein said rear bearing elements consist of at least two sliding tubular elements idly coupled to a second support pivot connected to said second frame.
  • 3. The armchair according claim 1, wherein said bellows comprises an elastically yielding body made of elastomeric material.
  • 4. The armchair according to claim 1, wherein the bellows has a prismatic frustum conical shape.
  • 5. The armchair according to claim 1, wherein said second elastic means comprises a pressure element anchored to a tubular member slidingly and rotatably coupled to a third support pivot connected to said second frame.
  • 6. The armchair according to claim 5, wherein said at least one pressure element is adjustable to change the thrust exerted on said backrest adjusting its inclination relative to said vertical axis (Z).
  • 7. The armchair according to claim 5, wherein said rotary translatory movements of said seat and said backrest are independent from each other.
  • 8. The armchair according to claim 5, wherein one or more armrests defining a third longitudinal axis (Y) generally orthogonal to said second longitudinal axis (X) are associated to said first frame.
  • 9. The armchair according to claim 8, wherein each of said one or more armrests can be tilted along said third longitudinal axis (Y).
  • 10. The armchair according to claim 8, wherein each of said one or more armrests are movable along said third longitudinal axis (Y).
  • 11. The armchair according to claim 1, wherein said thrust means comprises a stem having a first end acting against said end of said second frame, and a second end slidingly coupled in a guide hole made in a sleeve connected to said first frame, a helical spring being interposed between the ends and coaxially coupled to said stem having a first end resisted by a compression disc connected to said stem and a second end resisted by said sleeve.
  • 12. The armchair according to claim 11, wherein said second elastic means comprises a pair of cylindrical bodies made of elastomeric material and at least a pressure element slidingly and rotatably coupled to a third support pivot connected to said second frame.
  • 13. The armchair according to claim 12, wherein said pressure element comprises a first internally threaded tubular element provided with a transversal through hole adapted to slidingly receive said third pivot anda second externally threaded tubular element.
Priority Claims (1)
Number Date Country Kind
VI2000A0226 Oct 2000 IT
PCT Information
Filing Document Filing Date Country Kind
PCT/EP01/11923 WO 00
Publishing Document Publishing Date Country Kind
WO02/32260 4/25/2002 WO A
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