Patent ID: 8388298

Claim:
An apparatus for automatically correcting a positional deviation of a load lowered vertically by a transfer apparatus relative to both X and Y horizontal, two-dimensional directions, comprising: first and second pairs of load positioning apparatuses disposed, respectively, adjacent first and second diagonal corners of the load when the load is in a predetermined position, and each pair of load positioning apparatuses being positioned to meet vertical surfaces of the load in the predetermined position, which vertical surfaces cross at right angles; each load positioning apparatus including: a load supporting portion that supports a bottom face of the load movably in a horizontal direction; a movable table that can translate in horizontal, forward and backward directions within a predetermined range; a movable-table urging means for translating the movable table in a horizontal moving direction and for holding the movable table at a forward limit position; and a load positioning roller that is supported on the movable table by a horizontal supporting shaft perpendicular to the horizontal moving direction of the movable table; each load positioning apparatus is arranged so that the load positioning roller thereof adjoins a vertical surface of the load, when the load is supported in the predetermined position on the load supporting portion and when the movable table is at the forward limit position, and the horizontal moving direction of the movable table being perpendicular to the vertical surface of the load; each load positioning apparatus being operable, when the load is lowered in a deviated position wherein the load overlaps the load positioning roller when taking a plan view, to allow the movable table thereof to recede, together with the load positioning roller; and the movable-table urging means of each load positioning apparatus being operable, when the load is supported on the load supporting portion, to return the movable table to the forward limit position, together with the load positioning roller.