GB167037A - Improvements in drawing compasses - Google Patents

Abstract

167,037. Jackson, F. June 2, 1920. Compasses and dividers.-A compass is mada with a fixed leg 1 to which is secured a lug 3, the hinged leg 4, which is of flat section, being pivoted to the lug. As shown in Fig. 1 the leg 1 is of circular section and is forced through a hole in the lug, the upper end 2 of the leg being grooved to form a grip. The lug is formed with a slot to receive the end of the arm 4, which is mounted on a pivot 45 passing through the lug. When detachable pen or other points are to be used, the pen &c. is carried on a member 6 of square section, the side of the square being greater than the thickness of the leg 4 but less than its width. The leg is formed with a notch 5 and the member 6 with two slots, the two members fitting together as shown in Fig. 2. Means for adjusting the needle point are shown in Fig. 3. The tapered end 13 of the leg 1 is screwed on to the leg and is bored to receive the pcint 14, the upper end of the bore being tapped to receive a threaded adjusting-pin 15 which bears on the end of the needle point. A pencilholder may be secured directly to the flat arm by forming the arm with a tongue 21, Fig. 5, passing into an aperture in a member 20 which has a second aperture 22 through which passes the upper end 23 of the pencil socket 19. The needle point may have a protector consisting of a sleeve, slidable on the leg 1 and having a projection passing into a slot formed in the leg. To enable circles of comparatively large radius to be drawn with the leg 1 substantially vertical, the lug 3 may be arranged to slide on this leg and to he clamped in any desired position.