To provide a fastening control spring washer, a nut with the fastening control spring washer, a bolt with the fastening control spring washer and a fastening control method for bolt-nut in which cost reduction can be attained and fastening torque is simple to control.
A nut 5 with spring washer for fastening control comprises a nut 2, a dished spring washer (spring washer) 3 integrated with underneath of the nut, and a exfoliation layer 4 formed on the upper surface 3a of the dished spring washer 3 to cause a crack and separation by deformation of the dished spring washer 3. The method of fastening control of bolt-nut, comprises the steps of interposing the dished spring washer (spring washer) 3 formed the exfoliation layer 4 on the upper surface 3a either between a head 1b of the bolt 1 and one frame material A or between the nut 2 threadedly engaged with the bolt 1, deforming the dished spring washer 3 by fully tightening the bolt 1 or the nut 2, and exposing the upper surface 3a of the dished spring washer 3 by producing the crack and the separation on the exfoliation layer 4.
| WO2004016383 | SPLIT WELD CAGE NUT ASSEMBLY |
OKAMOTO KAZUO
ISHII TAKANORI
JAPAN POWER FASTENING CO LTD