DEVICE AND METHOD FOR MEASURING CAN BODY

PROBLEM TO BE SOLVED: To provide a device and a method for measuring a can body capable of executing the measuring without creating the deformation such as twist, of obtaining an accurate measurement result and of improving the reliability of the measurement result. SOLUTION: This measuring device 1 comprises a centering mechanism 10 for centering the can body 1B of which the opening faces downwardly, a holding mechanism 20 for attracting and holding the bottom of the centered can body 1B, a detector 34 that is inserted to the opening of the held can body 1B and obtains a distance to the can body 1B based on a reflected light from the can body 1B by emitting a light to the can body 1B and a relative rotating mechanism 35 for rotating the detector 34. As the measurement of an inner diameter of the can body 1B is executed in a non-contact manner, it is possible to prevent the can body from being deformed or twisted, to obtain the accurate measurement result and to improve the reliability of the measurement result.