GB619181A - Improvements in bow compass - Google Patents

Abstract

619,181. Compasses. BARTUSCH, A. P. Nov. 25, 1946, No. 34917. [Class 97 (iii)] The legs of a compass are formed from a pair of sections in transversely spaced relation from their upper pivoted ends to their lower free ends and are each provided with a combination spacer and nut member, maintaining the leg-sections at their fixed distance and receiving the end of an adjusting screw by means of which the position of the legs is adjusted. As shown in Fig. 2, the leg-sections 10 are held in annular grooves on the upper pivot member 11 by means of a spring 13 and are spaced by a member 14 having journals 15 and shoulders 17 and being threaded to receive a screw 21 which has right- and left-handed threads and a centrally disposed adjusting wheel 22. The inner surfaces of the lower ends of the leg-sections may be grooved to receive the point or pencil which is clamped in position by the knob 20, or, as shown in Fig. 5, the tool 26 may comprise a shank portion having a tongue 30 and shoulders co-operating with the opposing edges of the leg-sections and provided with a clamping screw 8 passing into a threaded bore in the tongue. Alternatively, the point may be supported between grooved clamping plates 27 which are rotatable on the screw 28 so that the points 25 may be reversed. In another modification the ruling pen is adjustably pivoted in the space between the fore-shortened end portions of the leg sections.