Device and method for use in adjusting the distance between two parallel surfaces

A device for use in adjusting within predetermined limits the distance between two parallel surfaces comprising:

• (a) an electrically insulating flat support having two separated electrodes on each side, one of the electrodes on each side being able to be connected to an electrical voltage source;
• (b) two resiliently deformable members having different resilient deformability from one another, each one being in contact with one side of the electrically insulating flat support in an area not covered by the two electrodes and projecting past the electrodes in a direction perpendicular to the plane of the electrically insulating flat support;
• (c) two electrically conductive members, each one in contact with one of the resiliently deformable members and extending over the two electrodes so that each can establish an electrical connection between the two electrodes when the resiliently deformable member is deformed by compression;
• and
• (d) a signaling circuit which signals when no electrodes are connected, when one pair is connected, or when both pairs are connected.