Pulsafeeder OMNI Series DC7 - Manual (Page 5)

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2.1 Reagent Head Assembly
The typical reagent head assembly consists of reagent head, diaphragm, and suction and
discharge cartridge check valves. This assembly is the only part of the pump to contact the
process liquid; consequently, maintenance is critical to pump performance.
2.2 Control Assembly
The OMNI ® pump incorporates a full motion style of stroke length adjustment. The stroke
length setting is indicated by a (0% – 100%) scale located on the stroke adjustment assembly.
Stroke length is changed by loosening the locking screw and turning the hand knob. This
turns a mechanism, which changes the amplitude of the stroke length. As the stroke
adjustment knob is turned towards 100%, it displaces the cam eccentrically to the rotating
drive shaft. This in turn causes the pushrod and diaphragm to travel over a longer distance.
Refer to Section 6.2 for further information.
For automatic flow rate control, users can consider the Pulsafeeder MPC speed based control
system, please contact your local Pulsafeeder dealer or representative for more information.
2.3 Gear Ratio Assembly
OMNI ® pumps are driven by an electric motor mounted on the motor adaptor input flange.
The motor drives a set of worm gears that convert rotational speed into torque. They, in turn,
power the eccentric shaft assembly that converts rotary motion into reciprocating motion.
The gear assembly and eccentric shaft run submerged in a lubricating oil bath.
Figure 2, isometric view