| 摘要 |
A gauge 10 for measuring angular displacement of a fastening element during tightening comprises a body 12, a drive transfer means 14 rotatable relative to the body, indicator means 16/18 for determining angular displacement of the drive transfer means relative to the body, and an optical means 20 for aligning the body with an arbitrary reference point. The optical means may be a light, preferably a laser. A switch 24 may be provided for operating the optical means. A battery compartment (38, Figure 4) may be disposed within the body. The indicator means may comprise an indicator dial 16 on the upper end of the body, and may also comprise a marker 36 disposed on the drive transfer means, which may extend substantially radially from an axis of rotation of the drive transfer means. The radial position of the marker may be angularly adjustable around the drive transfer means. The marker may be disposed on a transparent plastics disc 35. The body may be substantially tubular and terminated by a plate (26, Figure 4) at its upper end and open at its lower end. The drive transfer means may be rotatably mounted in an aperture in the disc and retained by means of a circlip (30, Figure 4). |
