Active Seating Apparatus and Method of Assembly and Use

Abstract

An active seating apparatus having a seat, a post configured for selectively engaging and supporting the seat and having a lower end opposite the upper end and seat formed with a post locking feature, and a base having an upper wall and an upwardly-opening receiver formed in the upper wall configured for selective removable receipt of the lower end of the post, the receiver having a receiver locking feature configured for selective locking engagement with the post locking feature upon insertion of the post within the base in selectively and securely assembling the post on the base through engagement of the post and receiver locking features, the surface-to-surface locking engagement between the post locking feature and the receiver locking feature being no more than twenty percent of the overall surface-to-surface contact between the lower end of the post and the receiver of the base.

1 . An active seating apparatus comprising:
 a seat;   a post configured for selectively engaging and supporting the seat at an upper end of the post, the post further having a lower end opposite the upper end and having a post locking feature formed at the lower end; and   a base having an upper wall and an upwardly-opening receiver formed in the upper wall configured for selective removable receipt of the lower end of the post, the receiver having a receiver locking feature configured for selective locking engagement with the post locking feature upon insertion of the post within the base in selectively and securely assembling the post on the base through engagement of the post and receiver locking features, the surface-to-surface locking engagement between the post locking feature and the receiver locking feature being no more than twenty percent of the overall surface-to-surface contact between the lower end of the post and the receiver of the base.   
     
     
         2 . The apparatus of  claim 1  wherein:
 the post locking feature comprises a plurality of spaced-apart angled radially-outwardly-protruding ramps; and 
 the receiver locking feature comprises a plurality of spaced-apart angled radially-inwardly-opening recesses that intersect the upper wall and are configured for receipt of the respective angled radially-outwardly-protruding ramps of the post, 
 whereby movement of the lower end of the post toward and rotationally relative to the receiver in selectively assembling the post on the base causes locking engagement of the angled radially-outwardly-protruding ramps within the respective angled radially-inwardly-opening recesses. 
 
     
     
         3 . The apparatus of  claim 2  wherein the plurality of angled radially-outwardly-protruding ramps are each at an angle to a post lengthwise axis of forty-five degrees and the plurality of angled radially-inwardly-opening recesses are each at an angle to a receiver lengthwise axis of forty-five degrees. 
     
     
         4 . The apparatus of  claim 1  wherein:
 the post locking feature comprises a radially-outwardly-projecting nub formed on the lower end of the post, the nub having a radially-outwardly-opening indent; and 
 the receiver locking feature comprises a radially-inwardly-projecting bump formed within the receiver, 
 whereby movement of the lower end of the post into the receiver in selectively assembling the post on the base causes locking engagement of the bump of the receiver within the indent on the nub of the post. 
 
     
     
         5 . The apparatus of  claim 4  wherein:
 the lower end of the post defines a post annular wall having a post thread; and 
 the receiver of the base defines a receiver annular wall having a receiver thread, 
 whereby rotational movement of the lower end of the post relative to the receiver in selectively assembling the post on the base causes threadable engagement between the post thread and the receiver thread. 
 
     
     
         6 . The apparatus of  claim 5  wherein:
 the nub is formed on an unthreaded portion of the post annular wall distal of the post thread; and 
 the bump is formed on an unthreaded portion of the receiver annular wall distal of the receiver thread, 
 whereby the threadable engagement between the post thread and the receiver thread causes the bump on the receiver to seat within the indent on the nub of the post. 
 
     
     
         7 . The apparatus of  claim 4  wherein the surface-to-surface locking engagement between the post locking feature and the receiver locking feature is no more than five percent of the overall surface-to-surface contact between the lower end of the post and the receiver of the base. 
     
     
         8 . The apparatus of  claim 1  wherein:
 the post locking feature comprises a radially-outwardly-projecting tab; and 
 the receiver locking feature comprises a radially-inwardly-opening groove, 
 whereby movement of the lower end of the post into the receiver in selectively assembling the post on the base causes locking engagement of the tab of the post within the groove of the receiver. 
 
     
     
         9 . The apparatus of  claim 8  wherein the receiver locking feature further comprises a radially-inwardly-opening slot proximal of and vertically offset from the groove. 
     
     
         10 . The apparatus of  claim 9  wherein:
 the slot intersects the upper wall of the receiver; and 
 the groove has a squared portion substantially circumferentially aligned with the slot and a sloped portion circumferentially offset from the slot, 
 whereby axial movement of the lower end of the post into the receiver first causes the tab to pass through the slot and then to transition out of the slot and into locking engagement within the squared portion of the groove, and 
 whereby rotational movement of the lower end of the post within the receiver shifts the tab from the squared portion of the groove to the sloped portion of the groove to facilitate axial withdrawal of the post from the base. 
 
     
     
         11 . The apparatus of  claim 10  wherein a radially-inwardly-projecting bump is formed in the groove between the squared portion and the sloped portion, whereby the bump must be overcome by the tab in shifting from the squared portion of the groove to the sloped portion of the groove. 
     
     
         12 . The apparatus of  claim 8  wherein the tab is located proximally on the lower end of the post and the groove is located proximally within the receiver of the base. 
     
     
         13 . The apparatus of  claim 12  wherein the tab is located on a flexible finger, whereby the tab may be selectively shifted out of contact with the groove to facilitate axial withdrawal of the post from the base. 
     
     
         14 . The apparatus of  claim 8  wherein the tab is distally tapered. 
     
     
         15 . The apparatus of  claim 8  wherein:
 the lower end of the post and the receiver of the base are both cross-shaped, the lower end of the post thereby having splayed post legs and the receiver of the base thereby having corresponding splayed receiver channels; 
 a tab is formed on at least two opposite post legs so as to extend radially-outwardly therefrom; and 
 a groove is formed in at least two opposite receiver channels so as to open radially-inwardly therefrom for selective engagement with the respective tab. 
 
     
     
         16 . The apparatus of  claim 15  wherein engagement of the post legs with the receiver channels is no more than net fit and is not an interference fit. 
     
     
         17 . The apparatus of  claim 8  wherein the surface-to-surface locking engagement between the post locking feature and the receiver locking feature is no more than ten percent of the overall surface-to-surface contact between the lower end of the post and the receiver of the base. 
     
     
         18 . The apparatus of  claim 1  wherein the lower end of the post and the receiver of the base are both annular, the lower end of the post thereby having a post annular wall and the receiver of the base thereby having a receiver annular wall. 
     
     
         19 . The apparatus of  claim 18  wherein engagement of the post annular wall with the receiver annular wall is no more than net fit and is not an interference fit. 
     
     
         20 . The apparatus of  claim 1  further comprising at least one friction pad configured for selective placement between the lower end of the post and the receiver of the base.