DRIVE MOTOR 2.11 The geroter (fig. C3487), is both a fluid displacement motor and a gear reducer. It provides 8 times (the number of star points) greater power per revolution than a gear, vane or piston type motor. This means that 8 times the greater torque can be developed at one eighth the speed without further gear reduction. 8 point star Roller (9) 2 Fluid pockets (9) C3487 Example shown in fig. C166 is one complete star orbit, or one sixth of the output shaft rotation.The star must travel through 6 complete orbits for each single rotation of the output shaft creating a speed reduction of 6 to 1.
The use of 7 fluid power pockets with the 6 to 1 ratio provides 42 fluid power cycles per each complete shaft revolution. NOTE: Actual star point count is 8. This is only an example. C166 2-26