To prevent components from being exposed in the upper face of a top place when an elevation table is in the raised position and expand an installation space for equipments on the elevation table and improve the appearance, etc.

This device is provided with a rotary link 11 and a connection link 13. The rotary link 11 has an upper arm section 11a which is rotatably engaged below a hood 6 of a desk 1 and is so structured as to be rotated upwards by being pushed up by an upper face of a rear part of an elevation table 9 when the elevation table 9 is raised from a stored position. The connection link 13 is directed nearly in the up and down direction and connects a lower part of the hood 6 and the rotary link 11 in linkage and is moved in a direction of opening the hood 6 when the upper arm section 11a of the rotary link 11 is moved upwards.