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Patent Searching and Data


Title:
METHOD AND APPARATUS FOR TIGHTENING BOLT
Document Type and Number:
Japanese Patent JPH11183280
Kind Code:
A
Abstract:

To obtain a method and an apparatus in which a specific axial force can be given to a bolt with good accuracy by irradiating the bottom part of a measuring hole with laser light from a laser displacement meter, performing the tightening operation of the bolt while the extension in the axial direction of the bolt is being measured, and finishing the tightening operation when the bolt reaches a specific extension.

A specific axial force is converted into the extension in the axial direction in the tightening operation of a bolt 5, and its numerical value is input to a controller 4. The bolt 5 is attached to a member to be tightened. A nut 6 is placed on a screw part, and the nut 6 is gripped and held by the gripping and holding part 31 of a tightening tool 3. On the other hand, the head part of the bolt 5 is restrained surely by the restraining part 12 of a bolt-head-part restraining jig 1. Laser light from a laser displacement meter 2 is shone at the bottom part of a measuring hole 52 in the bolt 5. The tightening tool 3 is operated while the extension in the axial direction of the bolt 5 is being measured, and the nut 6 is tightened. When the bolt 5 reaches a specific extension, the tightening tool 3 is stopped by a signal form the controller 4, and the tightening operation of the nut 6 is finished. Thereby, a specific axial force can be given to the bolt 5.


Inventors:
SAIGOU FUMITAKA
Application Number:
JP1997000367006
Publication Date:
July 09, 1999
Filing Date:
December 25, 1997
Export Citation:
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Assignee:
SANNOHASHI KK
International Classes:
G01L5/00; F16B31/02; G01B11/00; G01L5/24; (IPC1-7): G01L5/00; F16B31/02; G01B11/00; G01L5/24
Attorney, Agent or Firm:
山口 朔生 (外1名)