Abstract: A filing cabinet includes a safety interlock that prevents more than one drawer from being opened at a time. The safety interlock comprises a column of endwise abutting catches mounted to the cabinet wall for vertical reciprocation thereon. The ends of the catches are formed with tabs. The tabs of adjacent catches cooperate to define gaps of predetermined spacing. Actuator means on each cabinet drawer are aligned with the catch gaps. When a selected drawer is opened, the actuator means thereon enters the associated gap and displaces upwardly any higher catches. Upward displacement causes the gaps between higher adjacent catches to be displaced into the paths of the actuator means of any higher drawers, thereby preventing any higher drawers from being opened. The retainer of an open drawer blocks upward displacement of any lower catches, thereby preventing lower drawers from being opened. A slide is reciprocably mounted on each retainer.

Abstract: A cartridge for binding multi-page documents comprises a center member and a pair of side members pivotally connected to the center member. In the closed operative configuration, the side and center members cooperate to form a U-shaped channel for receiving the documents. Pins extending between and supported by the side members enter aligned holes in the documents for suspending them. The side members are provided with a lock for releasably locking the cartridge in the closed configuration. The lock comprises a first tab on one side member having an opening therein and a second tab on the other side member having a protrusion. The two tabs cooperate such that the second tab protrusion releaseably engages the first tab opening when the cartridge is in the closed configuration. The cartridge may be made with a T-shaped bar or a center hook suspension system.