Abstract: In a binding assembly for binders for holding a number of sheets of paper detachably bound together, the clamping unit, which includes a pair of metallic clamping plates for holding the paper therebetween, is detachably latched to a holder base which is in turn permanently attached to the binding of a binder. The clamping unit is provided with a bar extending across a cutout provided in a lower edge of each clamping plate, and the bar latches onto a latching mechanism provided in the holder base. Either one of the clamping plates may be selectively latched onto or unlatched away from the holder base while the other clamping plate is kept hinged to the holder base. The latching mechanism includes a pair of latch members made of plastic material, and slidably retained by a metallic base plate of the holder base, and the load applied to the clamping unit is primarily supported by the metallic base plate for minimizing the load applied to the latch members.

Abstract: A drawer apparatus includes a hollow housing, a tray slidably retained in the hollow housing, the tray being entered or drawn out from the housing through the open front surface thereof, and an urging device for urging the tray in a direction in which it protrudes from the open front surface of the housing. The urging device includes a constant-pressure spring, and a hook fixed to the other end portion of the constant-pressure spring, the hook being hooked to an open front edge portion of a bottom wall of the housing. A front frame is mounted on the housing. The front frame has a retaining portion which faces the open front edge portion of the bottom wall of the housing with the hook provided on the other end portion of the constant-pressure spring therebetween. A stopper member is provided on at least either an upper edge of a rear portion of the tray or an under surface of an upper wall of the housing which opposes the upper edge of the rear portion of the tray.

Abstract: A device for opening and closing a door hinged to a body includes a pair of bearing recesses formed in a face-to-face relation to each other in opposed inner wall surfaces of the body, bearing pieces rotatably accommodated one each in the bearing recesses, a pair of pivotable pieces provided one of each edge of the door at one end thereof and fitted in the bearing grooves, and a pair of guide grooves formed in a face-to-face relation to each other in the opposed inner wall surfaces of the body and each having one end communicating with one of the bearing recesses and extending inwardly of the body from the bearing recess. Each of the bearing recesses has a surface facing the other bearing recess and having a radial bearing groove extending from the axial center. The door is rotatably supported in the bearing recesses via the bearing pieces. When the door is opened, the guide grooves communicate with the bearing recesses.