Gear 1 rotates about fixed axis B and meshes with gear 4 which rotates about fixed axis C. Links 6 and 5 are connected by turning pairs D and E to gears 1 and 4, and by turning pairs A to connecting rod 3. Connecting rod 3 is connected by turning pair F to piston 2 which slides in fixed cylinder a. The dimensions of the links comply with the conditions: r₁=2r₄ and A͞D=A͞E, where r₁ and r₄ are the pitch radii of gears 1 and 4. When driving gear 1 rotates, point A describes complex connecting-rod curve q, and piston 2 reciprocates with two strokes of different length to each revolution of gear 1.
$2533$LrG,PM$