GB1463658A - Level- and angle-checking devices - Google Patents

Abstract

1463658 Levels W E SAVAGE 29 April 1974 [30 April 1973 26 June 1973 22 Oct 1973] 20390/73 30185/73 and 49035/73 Heading G1F A level or angle checking device comprises an enclosure formed of two flat transparent panels held in spaced parallel relationship by spacers which seal a compartment which is partially filled with a liquid and provided with at least one reference line which is parallel with a straight edge of at least one of the panels, so that when the straight edge is horizontal, the surface of the liquid is substantially in alignment with the reference line. The enclosure 1 may be defined by two parallel triangular or rectangular transparent sheets. In order to check angles, the enclosure is pivotally mounted on a backing sheet 9 which may be transparent. The enclosure 1 is pivoted about a shoulder 11 to the angle to be checked as measured on scale 15. The enclosure is locked in position by a wing nut and bolt arrangement Figs. 1 and 2 (not shown) or by a U-spring clip 23, 24 as shown. Thus when the base 10 is placed upon the surface to be checked, the liquid will align with line 5 (when in orientation shown) if the surface is at the correct angle i.e. at the angle set by scale 15. Other lines 6, 7 parallel to the other sides of a triangular enclosure may also be provided to allow any of the sides of a triangular enclosure to be abutted with the surface to be checked. A line 8 perpendicular to line 5 allows a check on perpendicularity. The liquid may be tinted paraffin and the enclosure may be of plastics material.