The mechanism is based on a four-bar sliding-link mechanism with two sliders, consisting of links 1, 2, 3 and 4. Added to this linkage is cross-shaped slider 5 having a stylus at its centre E. Links 1 and 3 have wheels 6 and 7 wi th sharp-edged rims. The mechanism is intended for tracing roulettes of circles. For this purpose, stylus E is placed on the curve with respect to which the roulette of a circle is to be obtained. Wheels 6 and 7 are set on a plane table. When stylus E is moved along the above- mentioned curve so that wheels 6 and 7 roll along the plane table, any point of plane member H, at tached to link 4, describes the corresponding roulet te of a circle. The mechanism can be set up for various circles by adjusting pivot C along the slot in link 2.
$1250$LG,Ge$