The invention provides a paper feed roller capable of reducing abnormal noise caused by a knurled shape while maintaining characteristics thereof, including maintaining friction coefficient and coping with paper powder. The paper feed roller comprises a roller body formed of elastic material in a cylindrical shape and is characterized in that the roller body has protruding lines and recessed grooves inclinedly extending relative to an axis of the roller body so that convex and concave portions having predetermined widths are alternatively formed in a circumferential direction of a peripheral surface, and the protruding lines have one-end side protruding line portions extending from a central part in an axial direction of the roller body toward one end thereof and other-end side protruding line portions extending from the central part in the axial direction toward the other end, and they are inclined relative to the axis in opposite directions.

The present technology relates to a reference point marking apparatus for marking reference points on a pattern electrode in which coated portions and uncoated portions are repeatedly arranged in a longitudinal direction, in which the pattern electrode includes a plurality of reserved electrode lane parts to be slit into a plurality of electrode lanes in the longitudinal direction in a subsequent process, and the reference point marking apparatus includes a moving marking machine configured to mark reference points on uncoated portions of the reserved electrode lane parts arranged in a width direction of the pattern electrode while moving in the width direction, and a controller configured to control an operation of the moving 10 marking machine. The present technology also provides a roll map generation apparatus using the reference point marking apparatus.

This measurement apparatus includes measurement markers (2) disposed on the outer circumferential surface of a drum (3), a band-shaped member (10) being arranged on the outer circumferential surface of the drum (3), at least one measurement sensor (4) that acquires position information on at least a portion of the measurement markers (2), and a calculator that calculates the position of the measurement markers based on measurement information on the measurement markers (2) acquired by the measurement sensor (4) and calculates misalignment between the actual position of the measurement markers (2) measured in advance and the calculated position of the measurement markers (2).