Bearing device for a chair with incline-adjustable back-rest bearer and incline-adjustable seat

Claim 1

In a bearing device for an incline-adjustable back-rest bearer and an incline-adjustable support plate for a seat of a height-adjustable chair, in particular an office chair, including a length-adjustable seat pneumatic spring on the bearing device connected by an articulated joint to the support plate, a length-adjustable back-rest pneumatic spring on the bearing device connected to the back-rest bearer by an articulated joint, a chair support column formed from a length-adjustable pneumatic spring which likewise is connected to the bearing device, the actuating rods of the seat pneumatic spring and of the back-rest pneumatic spring being directed towards each other and each one of the rods being in contact with one or two intermediate levers which are pivotably movable by means of an actuating lever movable in an approximately horizontal guide channel sot hat when the intermediate levers are in the position of their greatest displacement where the actuating rod concerned is pushed into the seat pneumatic spring or the back-rest pneumatic spring, they are arrestable and lockable into that position, and further including an actuating rod for the pneumatic chair support column located between the two intermediate levers which is actuated by the actuating lever, the improvement comprising: a detent lever associated and resiliently acting in conjunction with each of the intermediate levers, said detent levers being located above the chair support column, a corresponding detent lever engaging behind its respective intermediate lever after that lever is pivoted outwardly away from the actuating lever, and wherein said guide channel has a central vertically extending channel section to allow for the actuation of the actuating rod of the chair support column.