Pin wheel 1 with two pins a rotates about fixed axis A and meshes with teeth d of sprocket 2 which rotates about fixed axis B. The centres of the arcs at the top of teeth d lie on circle f. The profiles of teeth d consist of a circular arc at the top and two circular arcs a-a and a' -a' at the sides which are described from centre A. The remaining portions of the profiles are along curves which are equidistant to an epicycloid of a circle. Pitch radius r₁ of pin wheel 1 equals r₁=r+rₐ where r is the radius of pin a and rₐ is the radius of circular arcs a-a and a' -a'. When driving pin wheel 1 rotates continuously, driven sprocket 2 rotates intermittently with dwells during the periods when pin a engages arcs a-a and a'-a'. These arcs also serve as locking elements that prevent unintentional rotation of sprocket 2 during the dwells. To each revolution of pin wheel 1, sprocket 2 turns through an angle corresponding to two teeth d. When pin wheel 1 rotates at uniform velocity, sprocket 2 rotates at uniform velocity (during its rotation periods).
$2614$PG,D$