Purpose of "Supply Pump Assy" in CJV150 (Seen in Mechanical Drawing Rev 3.6)

[Marcos Duque]

Hello, my name is Marcos, and I’m not a native English speaker.
I have a CJV150 printer, and I noticed that the "Supply Pump Assy" is shown in the mechanical drawing Rev 3.6. However, I am unsure about its exact purpose. Could anyone explain what this component does in the printer?
Any clarification would be very helpful. Thank you!

 

[Smoke_Jaguar]

This is used when white ink is in the system to keep it mixed.