Abstract: A coupling between a twisted rod and a torsion spring of a spiral counterbalance is found to be subject to deformation against the twisted rod from compressive force of the grip of the terminal convolutions of the torsion spring. This problem is solved by using a metal cylinder in the rotation transmission sleeve of the coupling to resist the compressive force and prevent deformation so that the twisted rod can move freely within the coupling. This solution also allows the use of a stronger torsion spring to exert a larger counterbalance force.

Abstract: A guard guide surface for the lift-off slot of a tilt sash shoe is disposed obliquely above the lift-off slot to engage the head of a sash pin rising directly vertically from the slot. This prevents accidental withdrawal of a sash pin from a shoe when the sash is tilted. When the sash is slanted, however, for intentional withdrawal from a window, the sash pins can be lifted from their slots in off-vertical motions that clear the guide surface.

Abstract: An integral strip of resin material is used to cover exposed portions of jamb liner slots of take-out windows. Side walls on either side of the slot are displaced by passage of the tubular body. The winged flanges are drawn partly into the slot against outer portions of the side walls by a snap-fit engagement between inner portions of the side walls and the tubular part. Resilience of the winged flanges against the outer portions of the side walls helps to hold the strip in place and cover the slots. The tubular part of the strip also serves as a stop for limiting movement of a windown sash along the liner.

Abstract: Counterbalance mechanisms for a vertically movable sash have components extending downward within guides on which the sash moves. The guides can move laterally of the sash to allow the sash to tilt and be removed from the window, and the counterbalance components are arranged within the guides to accommodate such lateral movement. Slots in the guides accommodate interconnections between counterbalance components within the guides and the sash running vertically against outward surfaces of the guides, and these interconnections also allow lateral movement of the guides and tilting of the sash. The guides are mounted on window jambs by resilient elements that bias the guides into engagement with sash grooves and also accommodate lateral movement of the guides out of the sash grooves, to allow the sash to tilt.

Abstract: A lock shoe system for a take-out window having take-out jamb liners (10) uses a pair of fins (22) extending laterally outward from opposite sides (18) of a sash pin slot (16) in the jamb liner for supporting lock shoes (30) that move vertically in lock shoe channels (13 and 14) within the jamb liners. The lock shoes have pivotally mounted ramp latches (60) that extend over locking devices and are inclined toward recesses (82) for receiving sash pins (25). When a sash (20) is returned to an operating position between jamb liners (10), its sash pins (250 are moved downward over ramp latches (60), pivoting these aside and releasing the lock mechanism, which snaps the pins into the receiving recesses. This produces an audible sound as each pin is latched in its respective shoe (30) so that the user can tell from the sounds made when the latching occurs that sash (20) is properly latched into each shoe, where its weight is counterbalanced.

Abstract: A block and tackle balance system (10), contained within a spring cover (12) extending for the full length of a jamb liner (11), includes a guide (30) that directs a cord (25) through an angled course as it passes from the balance (20), through a hole (13) in the spring cover, to a support that moves up and down with a sash (15) outside the spring cover. The passing of the cord through the angled course in the guide produces load-related friction that helps prevent hop and drop of the sash. Guide (30) also preferably supports an end of the balance within the spring cover, and a support (50, 60) on the free end of cord (25) preferably engages sash (15) automatically as the sash assembled between a pair of jamb liners (11).

Abstract: A lock shoe system for a take-out window having take-out jamb liners (10) uses a pair of fins (22) extending laterally outward from opposite sides (18) of a sash pin slot (16) in the jamb liner for supporting lock shoes (30) that move vertically in lock shoe channels (13 and 14) within the jamb liners. The lock shoes bear against and ride on sash sides (24) of the fins, and the lock shoes have pivotally mounted biter knives (40) that can pivot into biting engagement with a frame side (26) of the fins to lock the shoes vertically in place. Arms (45) of the biter knives are engaged by pins (25) extending from the sash (20) into the slots for holding the knives clear of the fins whenever the sash is in its run. When the sash is removed from jamb liners (10), springs (50) on the lock shoes (30) bias the biter knives (40) into locking position against the force of the counterbalance springs (33), which bias the lock shoes upward.