Ramped-Key Keyboard for a Handheld Mobile Communication Device

Abstract

Wireless handheld mobile communication device and keyboard therefore having a keyfield including a plurality of depressible keys arranged in rows that are distributed about a vertical centerline (Vc) of the keyboard. Each depressible keys has a top engagement surface with an upper inboard portion that is raised relative a lower outboard portion thereof. The top engagement surface of each depressible keys is ramped from the lower outboard portion toward the upper inboard portion. Each top engagement surface is generally crest shaped, with the apex of the crest running generally diagonally across the respective key with a remaining surface falling away from the crest toward the upper outboard portion and the lower inboard portion of the key. The top engagement surface of each of the depressible keys terminates at an upper edge thereof in an elevated ridge down from which the balance of the respective top engagement surface slopes.

What is claimed is: 
     
         1 . A keyboard for a wireless handheld mobile communication device, the keyboard comprising:
 a keyfield comprising a plurality of depressible keys arranged in rows that are distributed about a vertical centerline of the keyboard, each of the depressible keys having a top engagement surface of which an upper inboard portion is raised relative a lower outboard portion thereof; and   at least one depressible key that spans the vertical centerline of the keyboard.   
     
     
         2 . The keyboard as recited in  claim 1 , wherein the top engagement surface of each of the plurality of depressible keys is generally upwardly convex about a diagonally running crest on the key. 
     
     
         3 . The keyboard as recited in  claim 1 , wherein the top engagement surface of each of the plurality of depressible keys has a generally inclined crest shape with a top of the crest diagonally oriented on the key. 
     
     
         4 . The keyboard as recited in  claim 3 , wherein the top engagement surface of each of the plurality of depressible keys falls downwardly away from the top of the diagonally oriented crest. 
     
     
         5 . The keyboard as recited in  claim 4 , wherein the inclined crest forms a ramped surface from the lower outboard portion toward the upper inboard portion. 
     
     
         6 . The keyboard as recited in  claim 5 , wherein a grade of the inclined crest on each of the plurality of depressible keys is substantially uniform from the lower outboard portion toward the upper inboard portion. 
     
     
         7 . The keyboard as recited in  claim 1 , wherein the top engagement surface of each of the plurality of depressible keys terminates at an upper edge thereof in an elevated ridge down from which the balance of the respective top engagement surface slopes. 
     
     
         8 . The keyboard as recited in  claim 7 , wherein each of the depressible keys has an upper side surface that slopes downward from the elevated ridge at a grade greater than any grade of the top engagement surface. 
     
     
         9 . The keyboard as recited in  claim 1 , wherein the at least one depressible key that spans the vertical centerline of the keyboard is disposed substantially normal to the vertical centerline. 
     
     
         10 . The keyboard as recited in  claim 1 , wherein the at least one depressible key that spans the vertical centerline of the keyboard is substantially centrally disposed with respect to the vertical centerline. 
     
     
         11 . The keyboard as recited in  claim 1  wherein the at least one depressible key that spans the vertical centerline of the keyboard has a substantially rectangular shape and rounded corners. 
     
     
         12 . The keyboard as recited in  claim 1  wherein the at least one depressible key that spans the vertical centerline of the keyboard comprises a SPACE key. 
     
     
         13 . The keyboard as recited in  claim 1 , wherein the plurality of depressible keys are at least substantially symmetrically disposed about the vertical centerline. 
     
     
         14 . The keyboard as recited in  claim 1 , wherein the keyfield is at least substantially symmetrically disposed about the vertical centerline. 
     
     
         15 . A wireless handheld mobile communication device comprising:
 a housing with a display located in a top portion thereof for displaying information and a keyboard located in a lower portion thereof below the display and wherein the keyboard comprises a keyfield having a plurality of depressible keys arranged in rows that are distributed about a vertical centerline of the keyboard, each of the depressible keys having a top engagement surface of which an upper inboard portion is raised relative a lower outboard portion thereof, and   at least one depressible key that spans the vertical centerline of the keyboard.