BOLT FASTENING METHOD AND DEVICE

• Main Authors: MAKIMAE TATSUMI, FUJII YUTAKA
• Format: Patent
• Language: English
• Published: 23.04.2009
• Subjects: COMBINED OPERATIONS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; HAND TOOLS; MACHINE TOOLS; MANIPULATORS; METAL-WORKING NOT OTHERWISE PROVIDED FOR; OTHER WORKING OF METAL; PERFORMING OPERATIONS; PORTABLE POWER-DRIVEN TOOLS; TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION; TECHNICAL SUBJECTS COVERED BY FORMER USPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TOOLS OR BENCH DEVICES NOT OTHERWISE PROVIDED FOR, FORFASTENING, CONNECTING, DISENGAGING OR HOLDING; TRANSPORTING; UNIVERSAL MACHINE TOOLS

PROBLEM TO BE SOLVED: To suppress fastening axial force variation even if snug torque is set higher in a bolt fastening method using a torque plus angle method. SOLUTION: A bolt is assumed to be further fastened by a set angle based on a bolt fastening angle when reaching the snug torque Ts after fastening the bolt until reaching the previously set snug torque Ts. Under this assumption, for determining the excess or insufficient fastening angle until reaching the snug torque Ts, a difference in an angular variation between the bolt fastening angle θsb when reaching the snug torque Ts and a reference angle θsa at the snug torque Ts is calculated, and a newly set angle obtained by adding the difference in the angular variation to a constant basic set angle is used to compensate the excess or insufficient bolt fastening angle. COPYRIGHT: (C)2009,JPO&INPIT