Abstract: A door latch has a latch bolt for being pivotally mounted on a door for 90.degree. angular movement between latched and unlatched positions, a retractable stop member pivotally mounted on the door and being spring biased for being engaged by the latch bolt for blocking the same in its unlatched position while the door is open. Upon closure of the door, the stop member engages an abutment adapted to be fixedly mounted on a doorframe and is thereby pivoted to a retracted position against the bias of the spring, so that the latch bolt is free to be moved between the latched and the unlatched positions only when the door is closed.

Abstract: A latch assembly comprises a bolt unit mounted in a frame member of a door or window sash, and a bolt-driving unit installed on one side of the door or window sash. The bolt unit has a latch bolt supported by a rotatable and axially movable shaft, the bolt being pivotable between projecting and retracted positions by rotation of the shaft. The bolt driving unit includes an axially movable driver torque bar having on one end a driver that is normally disengaged from the shaft. The shaft has thereon engaging means normally held in engagement with a support frame of the bolt unit. Upon axial movement of the torque bar toward the shaft, the driver is moved out of engagement with the fixed engaging means into driving engagement with the shaft. The engaging means on the shaft is shifted out of engagement with the support frame by continued movement of the torque bar, whereupon the shaft is free to rotate about its longitudinal axis.

Abstract: A latch assembly comprises a bolt unit mounted in a frame member of a door or window sash, and a bolt-driving unit installed on one side of the door or window sash. The bolt unit has a latch bolt supported by a rotatable hollow shaft, the bolt being pivotable between projecting and retracted positions by rotation of the hollow shaft. The bolt driving unit includes an axially movable driver torque bar having on one end a driver that is normally held in engagement partly with the hollow shaft in driving relation and partly with fixed engaging means of the bolt driving unit against rotation of the torque bar. By pushing the driver torque bar axially toward the hollow shaft, the driver becomes shifted out of engagement with the fixed engaging means, whereupon the driver torque bar can be turned about its own axis by an operator handle in order to rotate the hollow shaft for latching and unlatching operation.

Abstract: A latch assembly comprises a bolt unit mounted in a frame member of a door or window sash, and first and second bolt-driving units installed one on each side of the door or window sash. The bolt unit has a latch bolt supported by a rotatable hollow shaft, the bolt being pivotable between projecting and retracted positions by rotation of the hollow shaft. The first bolt-driving unit includes a first driver torque bar having one end spring-biased for insertion into the hollow shaft for driving engagement therewith. The first driver torque bar can be turned about its longitudinal axis by a handle. The second bolt-driving unit includes a second driver torque bar having one end spring-biased for withdrawal out of driving engagement with the hollow shaft. The second driver torque bar can be turned about its longitudinal axis by a knob. The handle is pivoted to actuate the latch bolt for normal latching and unlatching operation.

Abstract: A window includes a sash movable between closed and open positions while pivoting on a pair of slides which are vertically movable along the respective side posts of an outer frame. For pivotally connecting the sash to each slide, a pair of axially aligned longitudinally spaced sleeves are mounted on the top edge of the sash, one of the sleeves slidably receiving a pivot pin projecting from the slide. Rotatably arranged between the sleeves is an adjustor ring having a key projecting into the interturn spacing of a helical compression spring mounted within the sleeves and secured at one end to the pivot pin. The contact force of the slide on the side post is adjustable by the rotation of the adjustor ring relatively to the sleeves.