Anti-loosening adjustment bolt assembly

An anti-loosening adjustment bolt assembly, comprising:

• an adjustment bolt having a screw shaft threadably received from above in a female screw with an adjustable amount of tightening;
• a cylindrical pipe adapted to allow the screw shaft to be inserted therein and located at a fixed axial position relative to the female screw;
• and
• a nut having a threaded hole adapted to allow the screw shaft to be threadably received therein, the nut being threadably secured to a position on the screw shaft that is located higher than the upper end of the cylindrical pipe, wherein
• a bottom of the nut as determined along an axial direction includes a recess adapted to allow an upper end of the cylindrical pipe to be put thereinto,
• an inner peripheral surface of the recess is a taper surface decreasing in diameter toward an interior, and
• an axis of the taper surface is eccentric from an axis of the threaded hole such that, when the nut, threadably received in the screw shaft, is tightened toward the cylindrical pipe, the eccentric taper surface comes into pressure-contact with the upper end of the cylindrical pipe and the axis of the threaded hole of the nut is eccentric and/or inclined from an axis of the screw shaft to generate prevailing torque depending on an amount of tightening of the nut on the adjustment bolt.