| 摘要 |
PURPOSE:To prevent slip down of a member by means of a positioning control means, by a method wherein an attraction force is generated from an adsorbing surface, spaced close to the surface of a member to be held at a specified gap therebetween, through a high speed fluid film formed by injecting an air flow. CONSTITUTION:The under surface of an adsorbing plate 10 is a plane and forms an adsorbing surface 10a to which a base plate 7 is held. A ventilating hole 11 is bored in its central part, control members 14a, having thickness 0.2-0.8mm thicker than that of the base plate 7, are securely located to the corner parts of the surface 10a to prevent slip-down of the base plate 7. The base plate 7 is positioned below the surface 10a in a condition to feed air through the hole 11 and in a condition in that the diagonal line of the base plate 7 with the plate 10 is varied by 45 deg., the surface 10a approaches the base plate 7 to reduce a gap distance (d) to a fine gap distance of 0.2-0.8mm, air is exhausted in the distance (d) through the hole 11 at a high speed toward the outside to generate buoyancy by means of a negative pressure produced in the distance (d) to hold the base plate 7 in a non-contact state. |
