Patent ID: 7093392

Claim:
A slide shoe for a sash window unit, the shoe comprising: a body adapted to slide along a channel in a frame of the window unit; a socket in the body for pivotably receiving a boss mounted at the bottom of a window sash so that the sash can pivot about an axis at right angles to the direction of sliding movement of the shoe in the channel; an attachment point for one end of a spring balance; and means for rotating the attachment point to alter the amount of energy stored in a spring balance, when a spring balance is attached to the attachment point, wherein the means for rotating the attachment point comprises two meshing bevel gears arranged so that rotation can be applied on a first axis to produce rotation on a second axis substantially perpendicular to the first axis, wherein both axes are in the plane of the window, the first axis is at right angles to the axis of the spring balance, and the second axis is parallel to the axis of the spring balance, and wherein the means for rotating the attachment point comprising a ratchet mechanism that permits rotation in one angular direction and prevents rotation in the opposite angular direction, and wherein the ratchet mechanism has two opposed pawls that are spring loaded into contact with a cylindrical ratchet surface that rotates as part of the means for rotating the attachment point.