Height adjustable stand up desk

Abstract

An adjustable stand up desk includes a desk top; a desk base; leg assembly coupled to the desk top and the desk base; and an assisted lift mechanism. The assisted lift mechanism includes a gas spring coupled to the desk top and the leg assembly that assists in lifting and damping a first portion of travel of the desk top, and a spring device external to and in concentric alignment with the gas spring and sized and positioned to dampen a fall and assist a lift during a second portion of travel of the desk top.

We claim: 
     
         1 . An adjustable stand up desk, comprising:
 a vertically-movable desk top;   a desk base;   a leg assembly coupled to the vertically-movable desk top and the desk base; and   an assisted lift mechanism, comprising:
 a gas spring coupled to the vertically-movable desk top and the leg assembly that assists in lifting and damping a first portion of travel of the vertically-movable desk top, and 
 a spring device external to and in concentric alignment with the gas spring and sized and positioned to dampen a fall and assist a lift of a second portion of travel of the vertically-movable desk top. 
   
     
     
         2 . The desk of  claim 1 , wherein the gas spring comprises:
 a gas cylinder; and   a gas push in rod, wherein the spring device is positioned and has a length such that the spring device is engaged when the vertically-movable desk top is within approximately 25 percent of a desk top stowed, planar position.   
     
     
         3 . The desk of  claim 2 , wherein the spring device is free to move along a length of the push in rod. 
     
     
         4 . The desk of  claim 2 , wherein the spring device is fixed at one end. 
     
     
         5 . The desk of  claim 1 , wherein the spring device is a coil spring. 
     
     
         6 . The desk of  claim 1 , further comprising a removable safety bar positioned to stop a fall of the vertically-movable desk top. 
     
     
         7 . The desk of  claim 1 , wherein the leg assembly comprises a scissor lift assembly. 
     
     
         8 . A height-adjustable desk, comprising:
 a desk top;   a desk base;   a scissors-lift leg assembly slidably and pivotably coupled to the desk top and the desk base;   a first mechanism for extending the leg assembly from a stowed position to one of a plurality of extended positions and returning the an extended position to a stowed position, comprising:
 a differential pressure gas spring assembly, and 
 a pivotable handle that actuates the gas spring assembly, and 
   a second mechanism external to and in cooperation with the gas spring assembly that dampens a fall of the desk top to the stowed position and assists a lift of the desk top to the extended position; and   a safety mechanism that limits the fall of the desk top to the stowed position.   
     
     
         9 . The desk of  claim 8 , wherein the gas spring assembly comprises:
 a gas cylinder;   a differential pressure piston installed within the gas cylinder; and   a push in rod in connection with the piston, and wherein the second mechanism is in concentric free communication with the push in rod such that the second mechanism exerts a damping force on the gas cylinder during only the final 25 percent of the fall of the desk top.   
     
     
         10 . The desk of  claim 9 , wherein the second mechanism comprises a coil spring. 
     
     
         11 . The desk of  claim 8 , wherein the safety mechanism comprises:
 loops affixed to two legs of the leg assembly; and   a removable bar inserted through the loops.   
     
     
         12 . The desk of  claim 8 , wherein the desk top comprises a unitary surface. 
     
     
         13 . A portable, height-adjustable stand up desk, comprising:
 a desk top;   a desk base;   a leg assembly slidably and pivotably coupled to the desk top and the desk base;   a desk top lift mechanism for extending the leg assembly from a fully stowed, planar position to one of a plurality of extended positions and returning the leg assembly from an extended position to the fully stowed, planar position, comprising:
 a differential pressure gas spring assembly, 
 a pivotable handle that actuates the gas spring assembly, and 
 a spring mechanism external to and in cooperation with the gas spring assembly that dampens a fall of the desk top to the stowed position and assists a lift of the desk top to the extended position. 
   
     
     
         14 . The desk of  claim 13 , further comprising a safety mechanism that limits the fall of the desk top to the stowed position. 
     
     
         15 . The desk of  claim 13 , wherein the gas spring comprises:
 a gas cylinder; and   a push in rod, wherein the spring mechanism has a length such that the spring mechanism is engaged when the desk top is within approximately 25 percent of the desk top fully stowed, planar position.   
     
     
         16 . The desk of  claim 15 , wherein the spring device is free to move along a length of the push in rod. 
     
     
         17 . The desk of  claim 13 , wherein the leg assembly comprises a scissor lift assembly. 
     
     
         18 . A portable desk having a height-adjustable desk top, comprising:
 an extendible leg assembly coupled to the desk top; and   a lift mechanism that extends the leg assembly from a fully stowed, planar position to one of a plurality of extended positions and returns the leg assembly from an extended position to the fully stowed, planar position, comprising:
 a differential pressure gas spring assembly, 
 a handle that actuates the gas spring assembly, and 
 a spring mechanism external to and in cooperation with the gas spring assembly that dampens a fall of the desk top to the fully stowed, planar position and assists a lift of the desk top to the extended position. 
   
     
     
         19 . The portable desk of  claim 18 , further comprising a desk base, wherein the extendible leg assembly is coupled to the desk base. 
     
     
         20 . The portable desk of  claim 18 , wherein the gas spring assembly comprises:
 a gas cylinder; and   a push in rod, wherein the spring mechanism is positioned and has a length such that the spring mechanism is engaged when the desk top is within approximately 25 percent of the fully stowed, planar position.