Pin wheel 1 rotates about fixed axis A and carries three pins a which consecutively engage straight radial slots d of Geneva wheel 2. Geneva wheel 2 rotates about fixed axis B. Pins a are located at the same radius from point A with angles of 120° between lines joining their centres to point A. Slots d of Geneva wheel 2 are located symmetrically, also at angles of 120° between the axes of adjacent slots. Pin wheel 1 has three concentric locking surfaces b which engage concave locking surfaces e of Geneva wheel 2 to prevent its unintentional rotation during its idle periods. When pin wheel 1 rotates continuously at uniform velocity, Geneva wheel 2 rotates intermittently at nonuniform velocity and has three rotation periods tᵣ and three idle periods tᵢ. The time of one revolution of pin wheel 1 is T=3tᵣ+3tᵢ. The angles of rotation of pin wheel 1 corresponding to an idle and to a rotation period of Geneva wheel 2 are ϕᵢ=60° and ϕᵣ=60°. The angle of rotation of Geneva wheel 2 to each third of a revolution of pin wheel 1 is ϕ_G=120°. The rotation and idle factors are p=tᵣ/T= 0.1677 and q=tᵢ/T=0.1677. The working time coefficient is k=p/q=1. The transmission ratio from the Geneva wheel to the pin wheel is i₂₁=ω₂/ω₁=(λ(cos(ϕ₁)-λ))/(1-2λ cos(ϕ₁)+λ²) where λ= R/L, R is radius A͞D, L is centre-to-centre distance A͞B, ϕ₁ is the instantaneous angle of rotation of pin wheel 1 , and ω₁ and ω₂ are the angular velocities of pin wheel 1 and Geneva wheel 2. Pin wheel 1 and Geneva wheel 2 rotate in opposite directions.
$2629$PG,GW$