Abstract: A base plate for a closure mechanism of a loose-leaf holder for sheets defining holes along an edge thereof, the base plate carrying fixed, straight prongs for receiving the holes of the sheets and pivotal prongs cooperating with the fixed prongs, and the base plate being delimited by a first pair of parallel edges opposite each other and a second pair of parallel edges extending substantially perpendicularly to the first pair of edges, one of the edges of the first pair defining an inwardly projecting recess and the opposite edge of the first pair defining a protruding portion projecting outwardly in the same direction as the inwardly projecting recess.

Abstract: A closure mechanism for a loose-leaf holder for sheets defining holes along an edge thereof comprises a base plate, fixed prongs for receiving the holes of the sheets carried by the base plate, interconected prongs pivotal between a closed position wherein they cooperate with the fixed prongs and an open position, a connecting element carrying the pivotal prongs, and a spring held in the connecting element of the pivotal prongs and having a free end portion of the spring supported on the base plate, the spring biasing the pivotal prongs into the open position.

Abstract: A closure mechanism for a loose-leaf holder for sheets defining holes along an edge thereof comprises a base plate having a stiffening rib extending along an edge of the base plate and flaps stamped out of the base plate and bent upwardly about a common axis. Fixed prongs for receiving the holes of the sheets are fastened to the base plate along an opposite edge of the base plate, and commonly pivotal prongs having a loop portion cooperate with the fixed prongs upon pivoting the prongs into engagement with the fixed prongs.

Abstract: The invention relates to a device for holding sheets provided with perforations, preferably endless perforations, in a folder. The holding device comprises a base body portion (6) and a holding loop member (7) with two limbs (12,16). One limb (12) can be rotationally fitted into the base body portion (6) through the perforations in the sheets which are disposed one upon the other, whereas the other limb (16) can be resiliently retained in the base body portion (6) by turning the loop member (7).

Abstract: A clamping device for shackle mechanisms which can also be used as a tear-open safeguard and as a sheet turner consists of a flat body (8) with two L-shaped apertures (9,9'), one leg (10,10') of each aperture (9,9') extending parallel to the plane of the sheet shackels (17,17') and the legs (11,11') extending transversely thereto being arranged in line, also on the flat body (8) there are two hook-shaped portions (12,12') with a mouth (13,13'), this mouth (13,13') extending, over the distance of the sheet-shackle legs (4,5), parallel to the transverse leg (11,11') of the aperture (9,9') and the mouth (13,13') and transverse leg (11,11') being clampable firmly to the sheet-shackle legs (4,5).