GB722828A - Improvements in or relating to clinometers - Google Patents

Abstract

722,828. Clinometers. D'ENIS, F. B. Feb. 9, 1953 [Feb. 7, 1952], No. 3310/52. Class 97 (2). In a clinometer of the kind comprising an index member and an indicating scale of which one is rotatable with respect to the other about a horizontal axis and has secured thereto a pendulous mass in the form of a closed container partly filled with a heavy liquid such as mercury, the container is so shaped and dimensioned and contains a sufficient amount of liquid that when at rest the liquid is disposed close to or in contact with a central portion of the top wall of the container leaving unfilled spaces on either side of this central portion, so that upon oscillation of the rotatable element a surge is set up in the heavy liquid having a natural period of oscillation which is less than that of the pendulum system. The clinometer shown has a cylindrical casing 10 with a front transparent cover apertured at 12 and bearing a peripheral scale 15, and a rear wall 13 apertured at 14. A plate 26 bridging the aperture 12 and obscured from view by an opaque cover 27 supports, together with a plate 25 bridging aperture 14, a spindle 16 carrying four equispaced pointers 18. A bracket 19 extending from one pointer has clipped thereto an elongated container 21 partly filled with mercury. The container may be arcuate or V-shaped and may have a bulge 29 (Fig. 5) which is constantly filled with mercury. Preferably the mercury level is tangential to the upper arc of the arcuate container or intersects the upper V of the V-shaped container. A weighted bob 28, Fig. 4 (not shown) may be suspended from the container. In an alternative form, the scale may be connected to the spindle and one or more index marks may be provided on the casing.