| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a bumper reinforcement capable of being produced efficiently and having high strength to shock.SOLUTION: A bumper reinforcement is produced by following processes: a width direction intermediate part of one belt shape metal plate P is folded along a longitudinal direction of the metal plate P to form first and second folded parts which have gaps d1, d2 extending toward the longitudinal direction of the metal plate P in their internal parts; upper side and lower side cylindrical parts 20, 30 are formed by performing bending processing along the longitudinal direction of the metal plate P to parts respectively positioned between width direction both end parts and between the width direction intermediate part of the metal plate P so as to form spaces in their internal parts; and the width direction both end parts and the two folded parts are joined by calking the two folded parts in a state that the width direction both end parts of the metal plate P are respectively inserted into the gaps of the first and second folded parts.</p> |
