Patent ID: 6568771
Filing Date: 2003-05-27
Classification: E05B

Abstract:
An interlock system for a furniture article comprising a cabinet and at least two drawers, each of which is supported in the cabinet for movement between an open position and a closed position with respect to the cabinet;the system comprising: in association with each drawer, a cam unit that is mounted on the cabinet and includes a rotary cam assembly extending about an axis normal to the direction of movement of the associated drawer between its open and closed positions, the respective cam units being aligned on said axis; and an actuator element carried by the drawer; each cam assembly including a rotary cam and a stationary cam, the rotary cam being turnable about said axis by said actuator element in response to movement of the associated drawer between a normal position when the drawer is closed and an interlock actuating position when the drawer in open, the respective cams having co-operating cam surfaces shaped to cause (1) displacement of the stationary cam a pre-determined distance outwardly along said axis in response to turning of the rotary cam from said normal position to said interlock actuating position, and (2) locking of the cams with respect to one another in the event that said displacement of the stationary cam is prevented; said rotary cam including first and second tabs that project outwardly from said axis and are angularly spaced from one another, said first tab projecting into the path of said actuator element when the cam is in its said normal position, whereby the actuator element displaces the first tab and causes rotation of the cam to move the cam to its interlock actuating position and bring the second tab into position for contact by the actuator element when the drawer is returned to its closed position; said cam unit including a housing having a recess into which said first tab is displaced by the actuator element when the associated drawer is moved from its closed position to its open position, and in which the first tab is retained until the second tab is contacted by the actuator element as the drawer is returned to its closed position and the rotary cam begins to return to its said normal position; a locking element that extends between said cam units and connects the stationary cams of the respective units, the locking element being axially displaceable in response to said displacement of the stationary cam through said pre-determined distance; and, means limiting axial displacement of said locking element to said pre-determined distance so that the rotary cam of only one cam unit at a time can move to said interlock actuating position, whereupon the rotary cam of the other cam unit is locked in said normal position, each said rotary cam preventing opening of the associated drawer when the rotary cam is locked in said normal position.