Patent ID: 7069621

Claim:
A sash balance shoe comprising: a housing having a first length, adapted for moving along a second length of a window frame track positioned in a window frame, wherein paid housing is integral to said window frame and not integral to the sash, a first elastic element comprising a first end attached to said housing against movement in said housing along the first length, and a second end attached to a first pulley block that is movable in said housing along said first length, a second pulley block mounted in said housing fixed against movement in said housing along said first length, spaced from said first pulley block, a second element mounted in said second pulley block, rotatable about a first axis through said second pulley block by rotation of the sash out of the window frame when said second element is connected to the sash and the housing is mounted on the track, a cord operatively connected with said first and second pulley blocks, and a means for braking, configured for lateral extension from said second pulley block in response to rotation of said second element for engaging the frame for, preventing movement of said housing along the second length of the window frame track.