| 摘要 |
<p>An orientation testing device of the kind known as a "spirit level" (10) which comprises an elongate body (15) having at least one linear edge or planar face (11,12) and, mounted in an aperture (14,16) in the body(15), a closed generally tubular elongate translucent phial (17,18) that is partly filled with liquid to provide a gas (e.g. air) bubble (19,20) which by its position within the elongate phial is indicative of the orientation of the said linear edge or planar face (11,12). The elongate body (15) comprises a chamber (25) housing illumination means (24; 27,28,23,26,29,30) for illuminating the elongate phial. The provision of the illumination means (24; 27, 28, 23, 26, 29, 30) enables the phial and its gas bubble to be easily seen, especially when used in dark areas, for example in roofed-in partly-built buildings.</p> |
