Lockable elevating mechanism for the continuous adjustment of seats, table tops or similar items of furniture

In a lockable elevating mechanism for the continuous adjustment of chair seats, table tops or the like, a guide sleeve (1), attachable to a pedestal (4), and a length-adjustable lockable gas spring (8) are proposed, the piston rod (10) of which is connected axially fixed but detachable with the bottom of the guide sleeve (1). The housing (9) of the gas spring (8) can be connected axially fixed, but basically detachable, with a chair seat or the like by means of an upper fastening segment (21) seated in corresponding collar (22). An activating rod (26) extends upwardly from the housing (9). In order to easily detach the gas spring (8) from the chair seat or the table top, the housing (9) of the gas spring (8) is disposed radially fixed in an additional tube (20) having the fastening segment (21), wherein one end of the housing (9) axially rests against a stop in the area of the fastening segment (21) and wherein the other end rests against a fastening element (24), detachably connected with the tube (20).