Forward sliding reclining chair

Abstract

An office chair includes a seat and a backrest that are pivotally connected together at a pivot axis such that the backrest can pivot with respect to the seat between an upright position and a reclining position. The seat is mounted on a base such that the seat can move with respect to a base, and the seat includes front and rear portions that can pivot with respect to one another. When the backrest is pivoted from the upright position to the reclining position, both of the seat and the pivot axis move forward with respect to said base, and the seat front portion flexes with respect to the seat rear portion such that the angle between said upward faces of said seat front portion and the seat rear portion increases. The backrest may also include an upper portion and a lower portion that can pivot with respect to one another. When the backrest is moved to the recline position, the angle between the forward faces of the upper and lower backrest portions decreases.

1 . A chair for supporting a seated user on a floor surface while the seated user is performing tasks, comprising:
 a base;   a seat configured for forwardly guided movement with respect to said base, said seat including front and rear portions connected by a central flexible region enabling said seat front portion to flex with respect to said seat rear portion, each of said seat front portion and said seat rear portion including an upward face; and   a backrest pivotally connected to said seat at a first pivot axis such that said backrest can pivot with respect to said seat between upright and reclining positions, wherein movement of said backrest from said upright position to said reclining position causes both of said seat and said first pivot axis to move forward with respect to said base, and causes said seat front portion to flex with respect to said seat rear portion at said central flexible region, wherein the angle between said upward faces of said seat front portion and said seat rear portion increases.   
     
     
         2 . A chair according to  claim 1  wherein said forwardly guided movement of said seat and said angular increase between said upward faces of said seat front portion and said seat rear portion are proportional to said backrest rotation. 
     
     
         3 . A chair according to  claim 2  wherein said backrest includes a lumbar support pad mounted thereon and wherein said lumbar support pad is caused to move relative to said backrest in a direction toward the seated occupant's lower back as said backrest rotates from said upright position to said reclining position. 
     
     
         4 . A chair according to  claim 2  wherein said backrest has upper and lower portions connected by a flexible region therebetween, such that said upper portion can flex with respect to said lower portion at said flexible region, each of said upper and lower portions including a forwardly facing surface; wherein the angle between said forwardly facing surfaces of said upper and lower portions decreases as said backrest rotates from upright to reclining positions. 
     
     
         5 . A chair according to  claim 3  wherein said backrest has upper and lower portions connected by a flexible region therebetween, such that said upper portion can flex with respect to said lower portion at said flexible region, each of said upper and lower portions including a forwardly facing surface, wherein the angle between said forwardly facing support surfaces of said upper and lower portions decreases as said backrest lower portion rotates from upright to reclining positions. 
     
     
         6 . A chair according to  claim 5  wherein said backrest upper portion includes a generally upwardly extending headrest support structure and wherein said headrest support structure maintains its orientation relative to said base as said backrest lower portion rotates from upright to reclining positions. 
     
     
         7 . A chair according to  claim 1  wherein said seat rear portion includes at least one upwardly extending armrest structure extending therefrom. 
     
     
         8 . A chair according to  claim 5  wherein said backrest upper portion includes at least one forwardly extending armrest structure extending therefrom. 
     
     
         9 . A chair according to  claim 2  wherein the movement of said backrest with respect to said seat from said reclining position to said upright position, movement of the pivot axis rearwardly, and decrease in the angle between said upward faces of said seat portion are spring assisted. 
     
     
         10 . A chair according to  claim 2  wherein the movement of said backrest with respect to said seat from said reclining position to said upright position, movement of the pivot axis rearwardly, and decrease in the angle between said upward faces of said seat portion are driven by an electric motor. 
     
     
         11 . A chair comprising:
 a base;   a seat mounted on said base for movement with respect to said base, said seat having front and rear portions including substantially planar upwardly facing surfaces, said front and rear portions connected by a first flexible region enabling said seat front portion to flex with respect to said seat rear portion at said first flexible region; and   a backrest, said back rest having upper and lower portions including substantially planar forwardly facing surfaces, said upper and lower portions connected by a second flexible region enabling said upper portion to flex with respect to said lower portion at said second flexible region, wherein said backrest is pivotally mounted to said chair at a first horizontal pivot axis for movement between upright and reclining positions, wherein the angle between said upwardly facing surfaces of said seat front portion and said seat rear portion increases as said backrest is pivoted to said reclining position about said first pivot axis, and wherein said seat moves forward with respect to said base as said backrest is pivoted to said reclining position.   
     
     
         12 . A chair according to  claim 11  wherein the angle between said forwardly facing surfaces of the upper and lower portions of said backrest decreases as said backrest is moved to said reclining position. 
     
     
         13 . A chair according to  claim 12  wherein said chair includes a lumbar pressure arm and said backrest includes a lumbar support having a surface for supporting said seated user's lower back area, said lumbar support being mounted on a support arm, said support arm pivotally mounted to said backrest at a second pivot axis; said lumbar pressure arm mounted to said chair and configured to engage said lumbar support arm as said backrest rotates from said upright position to said reclining position, wherein the rotation of said backrest to said reclining position moves said pressure arm into engagement with said support arm, which moves said support arm and said lumbar support towards a seated user's lower back and consequently increases the engagement force of said lumbar support against said user's back. 
     
     
         14 . A chair according to  claim 13  wherein said movement between upright and reclining positions is powered by an electric motor. 
     
     
         15 . A chair including a base assembly for supporting the chair on a floor surface while a seated user is performing tasks comprising:
 a seat; and   a backrest, said backrest pivotally connected to said seat at a first horizontal pivot axis for movement of said backrest with respect to said seat between upright and reclining positions, wherein said seat is configured for progressive forwardly guided movement with respect to said base as said backrest reclines, said backrest including upper and lower portions connected by a flexible region therebetween, each of said upper and lower portions including a forwardly facing user support surface; wherein the angle between said forwardly facing user support surfaces of said upper and lower portions progressively decreases as said backrest rotates from said upright position to said reclining position.   
     
     
         16 . A chair according to  claim 15  wherein said flexible region does not move significantly rearward as said backrest is moved from said upright to said reclining position, and as said seat moves forward with respect to said base. 
     
     
         17 . A chair according to  claim 15  wherein said upper portion includes a generally upwardly extending headrest support structure and wherein said headrest support structure maintains its orientation relative to said upper portion as said backrest lower portion rotates from upright to reclining positions. 
     
     
         18 . A chair comprising:
 a base assembly for supporting the chair on a floor surface while a seated user is performing tasks;   a seat comprising a front portion and a rear portion that are pivotally connected therebetween at a first transverse horizontal pivot axis, wherein said seat rear portion is pivotally connected to said base at a second horizontal transverse pivot axis, said second pivot axis being located near a rear edge of said seat rear portion, wherein said second pivot axis is slidably guidingly supported on said base for generally horizontal movement along a first guide track, wherein a front portion of said seat front portion is pivotally connected to said base at a third transverse horizontal pivot axis wherein said third axis is guided on said base for generally forward and downward movement along a second guide track, said first transverse horizontal pivot axis being guided for generally forward movement by a third guide track;   a back support having a lumbar support area, said back support pivotally mounted to said seat rear portion at a forth transverse horizontal pivot axis located near a lower end thereof for pivotal movement with respect to said seat about said forth axis between upright and reclined positions;   a first linkage arm having one end pivotally mounted to said back support at a fifth transverse horizontal pivot axis, said fifth axis being located proximate said lumbar support area of said back support and wherein the other end of said first linkage arm is pivotally mounted to said base about a sixth transverse horizontal pivot axis, wherein said seat front and rear portions each include an upper surface, wherein said upper surfaces of said seat front and rear portions are substantially planar when said back support is in said upright position and wherein the angle between said upper surface of said seat front portion and said upper surface of said seat rear portion increases proportionally with respect to an increase of a recline angle of said back support, and wherein said fourth pivot axis moves forward with respect to said base assembly as said back portion recline angle increases.   
     
     
         19 . A chair according to  claim 18  wherein said base assembly is mounted on a floor supported base, said base assembly capable of swiveling about a first vertical axis with respect to said floor supported base. 
     
     
         20 . A chair according to  claim 18  wherein said back support includes an upper portion and a lower portion that are pivotally connected therebetween by a seventh transverse horizontal pivot axis, said seventh axis being located between said fifth axis and the upper end of said back support. 
     
     
         21 . A chair according to  claim 20  wherein an upper portion recline angle, defined between said upper portion of said back support and said lower portion of said back support, is controlled by a 4-bar linkage arrangement interconnected by 4-pivot axis so that said upper portion recline angle is different from a back support lower portion recline angle, defined between said seat and said back support lower portion, when said back support is reclined. 
     
     
         22 . A chair according to  claim 21  wherein said upper portion recline angle is less than said back support lower portion recline angle (with respect to vertical) when said back support is reclined. 
     
     
         23 . A chair according to  claim 22  wherein one bar of said 4-bar linkage arrangement is formed from a portion of said first linkage arm and one pivot axis of said 4-bar linkage is formed from said fifth axis. 
     
     
         24 . A chair comprising:
 a base assembly for supporting the chair on a floor surface while a seated user is performing tasks;   a seat supported on said base assembly;   a back support pivotally mounted to the chair at a first transverse horizontal pivot axis located near a lower end thereof for pivotal movement about said first axis between upright and reclined positions, wherein said first pivot axis moves forward with respect to said base assembly as said back support reclines;   a lumbar support having a surface for supporting said seated user's lower back area, said lumbar support being mounted on a support arm, said support arm being pivotally mounted to said chair at a second pivot axis; and   a pressure arm mounted to said chair, wherein said pressure arm is configured to move to apply proportionally increasing force against said support arm as said chair back support pivots from said upright position towards said reclined position when the lumbar support is engaged with the user's back.   
     
     
         25 . A chair comprising:
 a base assembly for supporting the chair on a floor surface while a seated user is performing tasks;   a seat having a front portion and a rear portion, wherein said seat is slidably guidingly supported on said base for generally horizontal forward and rearward movement with respect to said base along a first guide track;   a back support pivotally mounted to said seat at a first transverse horizontal pivot axis for pivotal movement between upright and reclined positions;   a lumbar support having a surface for supporting said seated user's lower back area, said lumbar support being mounted on a support arm, said support arm pivotally mounted to said back support at a second transverse horizontal pivot axis; and   a pressure arm mounted to said chair wherein said pressure arm is configured to move to apply proportionally increasing force against said lumbar support arm as said back support rotates from said upright position towards said reclined position.   
     
     
         26 . A chair comprising:
 a base assembly for supporting the chair on a floor surface while a seated user is performing tasks;   a seat having a front portion and a rear portion, wherein said seat is mounted to said base;   a back support having an upper portion and a lower portion that are pivotally connected therebetween at a first transverse horizontal pivot axis, said lower portion including a lumbar support area and said upper portion including an upper back support area defining a region generally aligned with and supporting the seated users' shoulder blades and the area therebetween, said first pivot axis located between said lumbar support area of the lower portion and said upper back support area of said upper portion, wherein said lower portion is pivotally mounted to said chair about a second transverse horizontal pivot axis for pivotal movement between upright and reclined positions, wherein said upper portion includes a third horizontal transverse axis horizontally spaced from said first pivot axis and pivotally connected to a first link arm near the upper end thereof, wherein said lower back support structure, said upper portion and said first link arm are 3-links of a 4-bar linkage and wherein said 4-bar linkage controls the angle of recline of said upper portion as said lower portion reclines.   
     
     
         27 . A chair comprising:
 a base assembly for supporting the chair on a floor surface while a seated user is performing tasks;   a seat including a front portion and a rear portion, wherein said seat is guidingly supported on said base for generally horizontal forward and rearward movement along a first guide track;   a back support pivotally mounted to said seat at a first transverse horizontal pivot axis for pivotal movement between upright and reclined positions, wherein said back support includes an upper portion and a lower portion that are pivotally connected therebetween at a second transverse horizontal pivot axis, said lower portion including a lumbar support area and said upper portion including an upper back support area defining a region generally aligned with and supporting said seated users' shoulder blades and the area therebetween, said first pivot axis located between said lumbar support area of the lower portion and said upper back support area of said upper portion and wherein said lower portion is pivotally mounted to said chair at a second transverse horizontal pivot axis near the lower end thereof for pivotal movement between upright and reclined positions, wherein said upper portion includes a third horizontal transverse axis located horizontally distant from said first pivot axis and pivotally connected to a first link arm near the upper end thereof, wherein said lower back support structure, said upper portion and said first link arm are 3-links of a 4-bar linkage and wherein said 4-bar linkage controls the angle of recline of the upper portion as said lower portion reclines.   
     
     
         28 . A chair according to  claim 27  wherein the recline angle of said upper portion, defined between said upper portion of said back support and said lower portion of said back support, is different from the recline angle of said lower portion, defined between said seat and said back support lower portion, when said back support is reclined. 
     
     
         29 . A chair according to  claim 28  whereby the length of said first link arm is adjustable 
     
     
         30 . A chair according to  claim 29  wherein said upper portion includes a generally upwardly extending headrest support structure that is substantially rigidly mounted to said upper portion so that said headrest support structure maintains its orientation relative to said upper portion as said lower portion is reclined. 
     
     
         31 . A chair including a base assembly for supporting the chair on a floor surface while a seated user is performing tasks comprising:
 a seat; and   a backrest pivotally connected to said seat at a first horizontal pivot axis for movement between upright and reclining positions, said seat configured for progressive forwardly guided movement with respect to said base as said backrest reclines, wherein the trajectory of movement of said seat with respect to said base is controlled by track followers on guide tracks, wherein said seat includes at least one track follower guided by a guide track included on said base and at least one guide track guided by a track follower included on said base.   
     
     
         32 . A chair comprising:
 a base assembly for supporting the chair on a floor surface while a seated user is performing tasks;   a seat comprising a front portion and a rear portion that are pivotally connected therebetween at a first transverse horizontal pivot axis, said seat front portion pivoted to said base at a second transverse horizontal pivot axis, wherein said second axis is guided on said base for generally forward and rearward movement along a first guide track; said rear portion of said seat pivoted to said base by a third transverse horizontal pivot axis, wherein said third axis is guided on said base for generally forward movement along a second guide track; said seat is pivoted to said base by a fourth horizontal transverse pivot axis, said fourth pivot axis being located generally between said second and third pivot axis, wherein said fourth pivot axis is guidingly supported on said base for generally horizontal movement along a third guide track;   a back support pivotally mounted to said seat about a fifth transverse horizontal pivot axis for pivotal movement about said fifth axis between upright and reclined positions, said back support including a sixth transverse horizontal pivot axis, said sixth axis spaced from said fifth axis and wherein said sixth axis is slidably guided on said base on a fourth guide track so that the trajectory of said sixth axis controls the extent of the pivotal recline motion of said back support about said fifth axis.   
     
     
         33 . A chair according to  claim 32  wherein said base assembly is mounted on a floor supported base, said base assembly capable of swiveling about a first vertical axis with respect to said floor supported base. 
     
     
         34 . A chair according to  claim 32  wherein said back support includes an upper portion and a lower portion that are pivotally connected therebetween by a seventh transverse horizontal pivot axis, said seventh axis being located between said fifth axis and the upper end of said back support. 
     
     
         35 . A chair according to  claim 34  wherein the recline angle of said upper portion of said back support with respect to said lower portion of said back support is controlled by a 4-bar linkage arrangement so that said back support upper portion recline angle is different from the recline angle of said back support lower portion with respect to said seat when said back support is reclined. 
     
     
         36 . A chair according to  claim 35  wherein the recline angle of said back support upper portion is less than the recline-angle of said back support lower portion when said back support is reclined. 
     
     
         37 . A chair comprising:
 a base;   a seat mounted on said base, said seat having front and rear portions including substantially planar upwardly facing surfaces, said front and rear portions connected by a first flexible region enabling said seat front portion to flex with respect to said seat rear portion at said first flexible region; and   a backrest, said backrest having upper and lower portions including substantially planar forwardly facing surfaces, said upper and lower portions connected by a second flexible region enabling said upper portion to flex with respect to said lower portion at said second flexible region, wherein said backrest is pivotally mounted to said chair at a first horizontal pivot axis for movement between upright and reclining positions, wherein the angle between said upwardly facing surfaces of said seat front portion and said seat rear portion increases as said backrest is pivoted to said reclining position about said first pivot axis, and wherein the angle between said forwardly facing surfaces of the upper and lower portions of said backrest decreases as said backrest is moved to said reclining position.   
     
     
         38 . A chair according to  claim 37  wherein said chair includes a lumbar pressure arm and said backrest includes a lumbar support having a surface for supporting said seated user's lower back area, said lumbar support being mounted on a support arm, said support arm pivotally mounted to said backrest at a second pivot axis; said lumbar pressure arm mounted to said chair and configured to engage said lumbar support arm as said backrest rotates from said upright position to said reclining position, wherein the rotation of said backrest to said reclining position moves said pressure arm into engagement with said support arm, which moves said support arm and said lumbar support towards a seated user's lower back and consequently increases the engagement force of said lumbar support against said user's back.