A window balance system includes a U-shaped channel with a first end and an opposite second end, and a balance element supported within the U-shaped channel. The balance element includes a fixed pulley block coupled to the first end of the U-shaped channel, a movable pulley block movably disposed in the U-shaped channel, and a cord extending between the fixed pulley block and the moveable pulley block. The window balance system includes a locking device coupled to the fixed pulley block and configured to engage with the cord and lock a position of the fixed pulley block with respect to the cord. The window balance system also includes a shoe coupled to the second end of the U-shaped channel. The shoe includes an elongate portion and an enlarged portion such that the shoe is substantially T-shaped, and a chamber configured to receive at least a portion of a pivot bar.

A window balance system includes a U-shaped channel with a first end and an opposite second end, and a balance element supported within the U-shaped channel. The balance element includes a fixed pulley block coupled to the first end of the U-shaped channel, a movable pulley block movably disposed in the U-shaped channel, and a cord extending between the fixed pulley block and the moveable pulley block. The window balance system includes a locking device coupled to the fixed pulley block and configured to engage with the cord and lock a position of the fixed pulley block with respect to the cord. The window balance system also includes a shoe coupled to the second end of the U-shaped channel. The shoe includes an elongate portion and an enlarged portion such that the shoe is substantially T-shaped, and a chamber configured to receive at least a portion of a pivot bar.

A door having a door body that can be lifted, along a predetermined path, from a closed position in which it closes a wall opening into an open position in which it is located substantially overhead, the door body having two, three or more door body elements arranged one on top of the other in the closed position, is modified according to the invention in that a lower edge of the door body in the closed position and trailing during the lifting can be lifted separately, when the door reaches the open position, by a pivoting movement of a lower door body element having said edge in a lifting direction with respect to a door body element situated above it in the closed position relative to the predetermined path.

A door having a door body that can be lifted, along a predetermined path, from a closed position in which it closes a wall opening into an open position in which it is located substantially overhead, the door body having two, three or more door body elements arranged one on top of the other in the closed position, is modified according to the invention in that a lower edge of the door body in the closed position and trailing during the lifting can be lifted separately, when the door reaches the open position, by a pivoting movement of a lower door body element having said edge in a lifting direction with respect to a door body element situated above it in the closed position relative to the predetermined path.

Disclosed are apparatus for a snap lock balance shoe and system to be incorporated in pivotable double hung windows. In one embodiment, the snap lock balance shoe includes a pair of retractable tabs that partially extend through openings within an inverted window balance.

Disclosed are apparatus for a snap lock balance shoe and system to be incorporated in pivotable double hung windows. In one embodiment, the snap lock balance shoe includes a pair of retractable tabs that partially extend through openings within an inverted window balance.

An inverted constant force window balance system has a carrier assembly including a housing with a first and a second housing wall, a coil spring with a free end, and a shoe assembly slidably coupled to the housing. The shoe assembly includes a first and a second shoe face. The housing slides between a first and a second position relative to the shoe assembly. When in the first position, the first and second housing walls are substantially non-coplanar with the first shoe face, and when in the second position, the first housing wall is substantially coplanar with the first shoe face and substantially non-coplanar with the second shoe face. The shoe assembly receives a pivot bar from a window sash and extends a brake upon rotation thereof. The balance system also includes a mounting bracket releasably coupled to the housing and coupled to the free end of the coil spring.

An inverted constant force window balance system has a carrier assembly including a housing with a first and a second housing wall, a coil spring with a free end, and a shoe assembly slidably coupled to the housing. The shoe assembly includes a first and a second shoe face. The housing slides between a first and a second position relative to the shoe assembly. When in the first position, the first and second housing walls are substantially non-coplanar with the first shoe face, and when in the second position, the first housing wall is substantially coplanar with the first shoe face and substantially non-coplanar with the second shoe face. The shoe assembly receives a pivot bar from a window sash and extends a brake upon rotation thereof. The balance system also includes a mounting bracket releasably coupled to the housing and coupled to the free end of the coil spring.

A window balance assembly may include a carrier, a spring element, and a mounting bracket. The spring element may include first and second portions. The first portion may be coupled to the carrier. The mounting bracket may engage the second portion of the spring element and may selectively engage the carrier.

A window balance assembly may include a carrier, a spring element, and a mounting bracket. The spring element may include first and second portions. The first portion may be coupled to the carrier. The mounting bracket may engage the second portion of the spring element and may selectively engage the carrier.