Abstract: An apparatus for determining the profile of a cylindrical workpiece whose radius varies with axial position. The apparatus is equipped with a spindle head and a pair of detectors. The spindle head supports and rotates the workpiece. The detectors are mounted on opposite sides of the axis of rotation of the workpiece and detect the position of the outer surface of the workpiece. When the workpiece is being rotated, the spindle head is moved parallel to the axis of the spindle. As a result, the detectors cross the outer surface of the workpiece. Also, the detectors are moved radially along an ideal profile of the workpiece in synchronism with the movement of the head. A control unit calculates the average of first and second output signals from the detectors, respectively, and produces the average as the profile error. In another embodiment, only one detector is used. The control unit measures the profile while the detector is positioned on one side of the axis of the spindle.

Abstract: A method for controlling an automatic sheet connecting and feeding apparatus in which folded sheets, each of which is folded zigzag in the form of a stack of sheets, are conveyed successively by a plurality of conveying means to a processing means. In order to connect the bottom sheet of a first one of the folded sheets to the top sheet of a second folded sheet following the first folded sheet the top sheet is lifted with a suction device. The step of lifting the first folded sheet includes the steps of pushing the suction device against the top sheet to suction and retain the top sheet, moving the suction device in parallel with the surface of the top sheet and moving the suction device in a direction perpendicular to the surface of the top sheet.