| 摘要 |
<p>PURPOSE:To keep a degree of preloading constant in a bid for stability all the time, by detecting a seat point of an inner race in a taper roller bearing, or rather a preload starting point, while clamping a nut as much as a fixed extent from this point of time and having the bearing preloaded. CONSTITUTION:A titled dT/dtheta of clamping torque T to a clamping vale theta of a nut 5 is electrically detected, and the nut 5 is rotated as much as a fixed number of times from the generation of this detection signal whereby preloading for a bearing is kept constant all the time. That is to say, a torque detector consisting of a strain gauge serving as a seat point detector 6 and a rotary encoder as an engine speed detector 7 both are added to a nut runner. With this method, since the nut 5 is able to detect its occupying of a C point with its own rotation, afterward, only when the nut 5 is rotated as much as the specified number of times, this nut 5 is clamped as tight as a specified clamping value phi irrespective of a fitting state between taper roller bearings 1 and 2 and a shaft 3.</p> |
