Vacuum cup

A vacuum device for attaching an object to a surface, comprising

• a body element fixable to said object;
• a piston element connected to said body element along a first sealing contour, thereby defining with said body element a first chamber, said piston element having a protruding sealing lip adapted to contact said surface along a second sealing contour, thereby defining with said surface a second chamber;
• said two chambers being connectable to a source of vacuum;
• said sealing lip being urged to said surface by a first sealing force due to the action of a vacuum created in said second chamber,
• said piston element being movable with respect to said body element by the action of a vacuum created in said first chamber and/or by an external force due to the contact of said sealing lip with said surface;
• wherein said vacuum device further comprises an elastic element connected to said piston element and said body element so as to deform when said piston element moves to reduce the volume of said first chamber, thereby creating a second sealing force urging said sealing lip towards said surface, which force is independent of said vacuum in said second chamber.