PURPOSE: To improve working efficiency by installing a movable shelf which can be raised freeky, supporting device which holds a pressing plate in free vertical elevation, and a guide rail which suspends the supporting device in free horizontally shiftable ways in the longitudinal direction of an iron-reinforced mat and conveying and laying the rion-reinforced mats one by one onto the movable shelf and once stroing and then transferring the mats into a storage box.

CONSTITUTION: An iron-reinforced mat whose main stem and sub stem are welded in a spot welder 29 is conveyed by a conveyance machine 30 and transferred onto a movable shelf 2 which is set at the height nearly equal to that of the upper surface of the conveyance machine 3. When the terminal edge of the mat 1 reaches the top edge of the conveyance machine 30, a cylinder 31 is operated to push the terminal edge of the mat 1 in the direction of advance, and push the terminal edge into the movable shelf 2. Then, a chain 9 is turned by a motor 13, and an angle fixed onto the chain 9 is lowered by one stage. Afterwards, the mats 1 are accommodated in succession into the movable shelf 2, and a prescribed number of mats 1 are accommodated. Then, a motor 22 is operated to lower a pressing plate 4, and the pressing plate 4 is moved leftward by a motor 18, and a group of mats 1 are transferred into a storage box 3.