BOLT

WIPO Patent Application WO/2012/070272

A1

Provided is a loosening prevention bolt having a simple and novel configuration and capable of reliably preventing loosening and of being repeatedly used in a wide range of construction processes. This bolt comprises: a bolt body; a diameter expanding member; and a fastening shaft portion. The bolt body includes a shaft hole in a shaft core portion, and also includes a space in the shape of a circular truncated cone. A plurality of slits for expanding the diameter is formed in the circumferential direction of a cylindrical portion in which the space is formed. The diameter expanding member is disposed in the space. The axial rotation of the diameter expanding member is prevented by a rotation prevention means. The diameter expanding member comes into contact with the inner wall of the cylindrical portion and includes a communication hole. The fastening shaft portion is inserted into the shaft hole of the bolt body and the communication hole of the diameter expanding member. A thread portion is formed on at least part of the outer periphery of the fastening shaft portion. With this configuration, the fastening shaft portion moves the diameter expanding member inside the space at the time of axial rotation and imparts the diameter expanding force to the bolt body.

HASEGAWA KENJI (JP)

PCT/JP2011/064812

May 31, 2012

June 28, 2011

Click for automatic bibliography generation  

HAMA SYSTEM CORP (JP)
HASEGAWA KENJI (JP)

F16B39/02

JP2000346035A	2000-12-12
JP2003239925A	2003-08-27
JP2005325948A	2005-11-24
JPS6232218U	1987-02-26
JPH05209612A	1993-08-20
JPH074417A	1995-01-10
GB2417537A	2006-03-01
JPH0526218A	1993-02-02
JPH0647722U	1994-06-28

SATOH, TAKAHISA (JP)
Takahisa Sato (JP)

View/Download PDF      PDF Help

Previous Patent: STEEL SHEET OF STRAIN AGING HARDENING TYPE WITH EXCELLENT AGING RESISTANCE AFTER PAINT BAKING AND PR...

Next Patent: IMAGE DISPLAY APPARATUS AND ANTI-COPYING DEVICE USED THEREFOR