DRESSTA TD-25M EXTRA, Service Manual

Page: 370 / 595

SECTION 10A
PUMPS
Page 4
TD-25M EXTRA DRESSTA
EQUIPMENT PUMP
Fig. 10A.4. Vane Pump Cartridge Action
1. Rotor Ring
2. Inlet
3. Rotation 4. Outlet
5. Inlet
6. Drive Shaft 7. Rotor
8. Outlet
9. Vane 10. Outlet
11. Rotation
12. Inlet
As previously mentioned, fluid flow is developed by the pumping cartridge (Fig. 10A.4). The rotor
is driven within the rotor ring by the drive shaft. As rotor turns, centrifugal force causes the vanes to
follow the elliptical inner surface of the rotor ring. Radial movement of the vanes and turning
of the rotor cause the chamber volume between the vanes to increase as the vanes pass the inlet
section of the rotor ring. This results in a low pressure condition which allows atmospheric pressure
to force fluid into the chambers. Fluid outside the inlet is at atmospheric pressure or higher.
Fig. 10A.5. Cutaway of Pumping Chamber
1. Pressure Plate
2. Cover
3. Back Pressure in System Effective Here
4. Discharge 5. Rotor Ring
6. Vane
7. Rotor 8. Shaft
9. Spring
10. Pressure in Cartridge