Forward-biased postural chair

Abstract

A chair having a back portion that is slidably biased with respect to a seat portion. The back portion slides forward against the occupant's back as the occupant slides forward in the seat. The occupant may set an initial position of the back portion if she or she wishes to sit back in the chair. Optional folding armrests slide together with the back portion. The back portion may also tilt with respect to the seat portion so as to better conform to the occupant's back.

1 . A seating apparatus to support a user in a sitting position, comprising:
 a seat portion;   a back portion; and   a positioner configured to allow the back portion to translate along a translational axis, the positioner being further configured to bias the back portion in a first direction along the translational axis with respect to the seat portion and to inhibit the back portion from moving in a second direction, which is substantially opposite the first direction, with respect to the seat portion.   
   
   
       2 . The seating apparatus of  claim 1  wherein the positioner comprises:
 a guiding element; and   a controller;   the guiding element configured to guide the controller along the translational axis;   the controller being attached to the back portion;   the controller having a first tendency to translate in the first direction along the translational axis;   the controller having a second tendency to remain stationary when pressure is applied to the back portion in the second direction.   
   
   
       3 . The seating apparatus of  claim 2  wherein:
 when the controller has traveled along the first direction to the end of the guiding element, the back portion is positioned substantially directly over the center of the seat portion; and   when the controller has traveled along the second direction to the opposite end of the guiding element, the back portion is positioned substantially adjacent to an edge of the seat portion.   
   
   
       4 . The seating apparatus of  claim 2  wherein:
 when a control element is activated, the back portion is configurable to tilt around a tilt axis which is substantially perpendicular to the translational axis; and   when the control element is deactivated the back portion does not tilt about the tilt axis.   
   
   
       5 . The seating apparatus of  claim 2  wherein:
 the seat portion defines a first plane;   the back portion defines a second plane;   the translational axis is substantially parallel to the first plane and substantially perpendicular to the intersection of the first and second planes.   
   
   
       6 . The seating apparatus of  claim 5  wherein:
 when a control element is activated, the back portion is configurable to tilt around a tilt axis which is substantially parallel to the intersection of the first and second planes; and   when the control element is deactivated the back portion does not tilt about the tilt axis.   
   
   
       7 . The seating apparatus of  claim 2  wherein the controller is configured to accept an initial position along the guiding element as set by the user. 
   
   
       8 . The seating apparatus of  claim 7  wherein:
 the guiding element is comprised of a tube having a series of collinear holes positioned thereon;   a spring is positioned over a portion of the guiding element such that when the spring is compressed it exerts a force on the controller in the first direction;   the controller comprises:
 a pull handle coupled to a pin configured to enter any of the holes on the guiding element; 
 a light compression spring positioned around the pin to exert a force on the pin in the direction of the guiding element; and 
 the end of the pin having a curvature such that when pressure is exerted against the controller in the first direction the pin tends to slide out of a hole on the guiding element, but when no pressure is exerted against the controller in the first direction the pin tends to remain in a hole on the guiding element; and 
   when the pull handle on the controller is pulled away from the guiding element the user may position the controller along the guiding element by applying force against the back portion.   
   
   
       9 . The seating apparatus of  claim 2  wherein the controller also attaches to armrests, allowing the armrests to translate together with the back portion. 
   
   
       10 . The seating apparatus of  claim 9  wherein the armrests are hinged such that the armrests may be folded out and away from the seating apparatus. 
   
   
       11 . The seating apparatus of  claim 1  wherein the positioner comprises:
 a first guiding element;   a first controller;   a second guiding element; and   a second controller;   the first guiding element configured to guide the first controller along the translational axis;   the first controller being attached to a first side of the back portion;   the second guiding element configured to guide the second controller along the translational axis;   the second controller being attached to a second side of the back portion;   each controller having a first tendency to translate in the first direction along the translational axis;   each controller having a second tendency to remain stationary when pressure is applied to the back portion in the second direction.   
   
   
       12 . A method for controlling the position of a back portion of a chair comprising:
 setting an initial position of the back portion; and   translating the back portion forward when the occupant moves forward in the chair;   
   
   
       13 . The method of  claim 12  wherein:
 the setting step comprises deactivating a controller and leaning back against the back portion until the back portion is in the desired initial position and then reactivating the controller; and   the translating step comprises biasing the controller forward as the occupant of the chair moves forward in the chair, such that the forward motion of the controller translates the back portion forward against the occupant's back.   
   
   
       14 . The method of  claim 13  wherein:
 the controller becomes deactivated when a control handle located on the controller is pulled;   the controller becomes reactivated when the control handle is released.   
   
   
       15 . A seating apparatus to support a user in a sitting position, comprising:
 first means for supporting the buttocks of the user;   second means for supporting the back of the user; and   third means for allowing the first means to translate along a translational axis, the third means being further configured to bias the second means in a first direction along the translational axis with respect to the first means and to inhibit the second means from moving in a second direction, which is substantially opposite the first direction, with respect to the first means.