PURPOSE: To make a paper sending process accurate by a method wherein an elevator system is installed on a blank form loading stand of an optional letter reading device, and a bend of a blank form sending roller is detected, through which the elevator system is so constituted that it moves up and down.

CONSTITUTION: A sending roller 3 is made to touch the upper surface of a blank form 2, and the roller 3 is made to roll to an arrow direction for sending operation. Simultaneously with the sending process a detecting lever 13 is lowered, and the blank form loading stand 9 is lifted up through driving by a pinion 12 when a press part 17 of a lower detector 16 is pressed by the tip of the detecting lever 13. Therefore, the detecting lever 13 is moved upward for removal from the detector 16, causing an upper detector 16' to be actuated and stops the driving of the pinion 12. Through a repetition of this process a contact pressure between the sending roller 3 and the blank form can be kept favourable automatically and an accurate sending process can be made possible.