Face cam 1 has a symmetrical profiled groove a consisting of six identical portions and rotates about fixed axis A. Followers (piston rods) 4 reciprocate a long fixed guides b and carry rollers 3 which roll and slide along groove a. Followers 4 are rigidly attached to pistons 2 which reciprocate in the cylinders of fixed cylinder block 5. Positive motion is achieved because the diameter of roller 3 is equal to the width of groove a. The axes of the cylinders are at angles of 120° with each other.
$3264$CmL,PM$