Working of Rotor Pump.

Don't Click Here: This is now widely used in automobile as the engine pump (FIP: fuel injection pump).
Click Here: Kerala Kitchen (Cookery channel)

Main component of a rotor pump:

1. Internal gear (driving gear): As shown in the figure the internal gear is called as the driving gear as it gets the drive from the engine and it drives the external gear.
2. External gear (driven gear): As shown in fig, the internal gear drives the external gear and hence called the driven gear, it have more no: of lobes compared to the internal gear.
3. Pump housing: This is the casing in which the gears rotate.--Technical Videos--

Working of a Rotor pump:Don't Click Here:

Fig: 1

Rotor Pump

The working is similar to Gear pump, the drive from the Engine reached the internal gear (driving gear) which intern meshes with the External gear (driven gear), as you can see in the fig: the number of lobes of the external gear is more compared to the internal gear. This is designed in such a way that, the axis of rotation of the internal gear is different from that of the external gear, so the number of lobes differs.

The spaces between the lobes carry the oil, as the gears disengages due to the low pressure created the fluid (fuel) is sucked through the inlet port and is trapped between the lobes as shown in green in the fig:, as the gears rotates the teeth’s comes in contact and pushed the oil out through the out let pot. This how simply as rotor pump works.

This type of pump is more efficient and compact than the gear pump, they make less sound due to less no: of teethes in mesh.--Technical Videos--