Improvements in Apparatus for Measuring the Linear Expansion of Solids.

摘要

13,368. Horne, W. J. A. E. May 30. Heat and temperature coefficients, apparatus for determining.-Apparatus for measuring the linear expansion of solids, for determining the coefficient of expansion, comprises a support carrying duplicate specimens which are heated to different temperatures by fluid media and have means enabling the variation in length to be measured. The specimens b, b1, which may be tubes or rods enclosed in tubular jackets, are supported loosely by a clamp c and firmly by the pointed ends of adjusting-screws a2, e entering indentations f. Each tube has pipes n, o for the conveyance of the heating- fluid, and a thermometer u. An arm g1 and a forked arm g partly surrounding it are secured to the tops of the specimens. The difference in the lengths of the rods may be measured by means of a micrometer gauge j, which is fixed in a slot j1 in the arm g, Fig. 3, by a screw j2, and is adjusted until a bridge-piece k, carried partly by it and partly by a rib k1 engaging in a V-groove in the arm g1, is horizontal, as indicated by a level l. The arms g, g1 may also have an ' anvil ' i permitting measurement by a spherometer, ribs m, m1 for use with sliding callipers, and knife-edges p, p1 to carry a pointer for use with a scale. The measurement may also be taken by means of a beam of light reflected on to a scale by a mirror mounted on a stand carried partly by each arm.