A counterbalance system that is set into the guide track of a tilt-in window. The counterbalance system utilizes a brake shoe that is attached to a ribbon spring. The ribbon spring has a shaped head that is retained by the brake shoe. A flexible tab is formed in the ribbon spring near the shaped head. A protrusion extends from the brake shoe. The brake shoe has a receptacle that receives and retains the shaped head of the ribbon spring, therein interconnecting the ribbon spring to the brake shoe. A cam is supported within the brake shoe. The brake shoe expands when the cam is turned. This causes the protrusion on the brake shoe to be biased against the flexible tab in the ribbon spring. This, in turn, causes the flexible tab to flex and extend away from the ribbon spring at an inclined angle. Within the guide track of the tilt-in window, the extended flexible tab acts as a barb and engages the side wall of the guide track. This helps prevent the window sash from being moved when the window sash is tilted open.

A counter balance device for a sash window includes a spiral balance having a hand-wound spiral rod connected to wind a torsion spring to generate an initial spring force that counter balances the window's weight for keeping the sash up when raised. The lower end of the spiral rod is connected to a rotation shaft rotatably disposed on a slide block. When a large repulsion force produced by the torsion spring is applied to the spiral rod, the rotation shaft is urged in a direction reverse to the rotation direction of the spiral rod by a buffer spring having a spring force which is larger than the initial spring force so that the rotation of the rotation shaft is tolerated.

An inverted constant force window balance system includes a carrier assembly and a mounting bracket. The carrier assembly includes a housing, a coil spring disposed within the housing, and a shoe assembly coupled to the housing. The shoe assembly is configured to receive a pivot bar from a window sash and extend at least one brake upon rotation of the pivot bar. The mounting bracket is releasably coupled to the housing opposite the shoe assembly and is coupled to the free end of the coil spring. At least a portion of the mounting bracket is configured to slideably move in relation to the free end of the coil spring between at least two positions. When at least a portion of the mounting bracket moves between the at least two positions, the mounting bracket disengages from the housing and releases the mounting bracket from the carrier assembly.

A door braking system includes: a shaft; a brake pad configured to be mounted to the shaft; a plate for mounting on the shaft adjacent to the brake pad; a spring for urging the plate to the brake pad, the spring configured to be mounted on the shaft; a nut dimensioned and sized to be mounted on the shaft for adjusting an amount of force the spring urges the plate against the brake pad. A method of applying variable amount of braking force to a door includes: attaching a brake pad and brake plate to a shaft; configuring a spring to urge the brake plate against the brake pad; mounting an adjustment piece to the shaft; and configuring the adjustment piece to move axially on the shaft as the shaft rotates to thereby vary a force the spring urges against the brake plate.

A corner key assembly for a sliding panel system including a panel frame and a movable panel can include a corner key including a distal and proximal end, and a guide chamber being defined in the corner key, the guide chamber extending from the distal end towards the proximal end of the corner key; a guide slidingly movable relative to the corner key, at least a portion of the guide being configured to be positioned in the guide chamber and a portion of the guide being configured to extend from the guide chamber; and a biasing element positioned in the guide chamber between the guide and the proximal end, the biasing element configured to urge a portion of the guide from the guide chamber away from the corner key and into frictional engagement with the panel frame to hold the panel in a desired position relative to the panel frame.

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 includes a carrier assembly and a mounting bracket. The carrier assembly includes a housing, a coil spring disposed within the housing, and a shoe assembly coupled to the housing. The shoe assembly is configured to receive a pivot bar from a window sash and extend at least one brake upon rotation of the pivot bar. The mounting bracket is releasably coupled to the housing opposite the shoe assembly and is coupled to the free end of the coil spring. At least a portion of the mounting bracket is configured to slideably move in relation to the free end of the coil spring between at least two positions. When at least a portion of the mounting bracket moves between the at least two positions, the mounting bracket disengages from the housing and releases the mounting bracket from the carrier assembly.

An inverted constant force window balance system includes a carrier assembly and a mounting bracket. The carrier assembly includes a housing, a coil spring disposed within the housing, and a shoe assembly coupled to the housing. The shoe assembly is configured to receive a pivot bar from a window sash and extend at least one brake upon rotation of the pivot bar. The mounting bracket is releasably coupled to the housing opposite the shoe assembly and is coupled to the free end of the coil spring. At least a portion of the mounting bracket is configured to slideably move in relation to the free end of the coil spring between at least two positions. When at least a portion of the mounting bracket moves between the at least two positions, the mounting bracket disengages from the housing and releases the mounting bracket from the carrier assembly.

A snap lock balance shoe of a balance system may 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 channel. The shoe includes a locking member that extends toward a window jamb when a cam of the shoe is rotated. This extension locks the balance system in place in the window jamb. During a method of assembly of the balance system, the snap lock balance shoe may be engaged with the channel and then pivoted to secure the snap lock balance shoe to the channel.

A door braking system includes: a shaft; a brake pad configured to be mounted to the shaft; a plate for mounting on the shaft adjacent to the brake pad; a spring for urging the plate to the brake pad, the spring configured to be mounted on the shaft; a nut dimensioned and sized to be mounted on the shaft for adjusting an amount of force the spring urges the plate against the brake pad. A method of applying variable amount of braking force to a door includes: attaching a brake pad and brake plate to a shaft; configuring a spring to urge the brake plate against the brake pad; mounting an adjustment piece to the shaft; and configuring the adjustment piece to move axially on the shaft as the shaft rotates to thereby vary a force the spring urges against the brake plate.