4
Pump P-910
Instructions 56-3000-47 Edition AD
Reference information
Description
A stepper motor in the pump housing drives a
roller cage that provides the pumping action.
The asymmetric pressure plate ensures the pump
has a low pulsation characteristic. Control of
the pump is provided from a PC running
UNICORN, version 2.10 or higher. The power
is supplied from a system pump in the
ÄKTAdesign Pump P–900 series.
Roller cage
The roller cage contains six polytetrafluoro-
ethylene pumping rollers mounted between
two aluminium plates, which hold the roller
bearings. As the cage rotates, the rollers
rotate in the opposite direction, driven by
drive wheels which engage the chassis ring.
The roller diameter and the gear ratio ensure
that the rollers in contact with the pump
tubing are stationary with respect to
the tubing. Waves of compression pass along
the tubing without dragging the tubing in
the direction of movement of the roller cage.
Pressure plate
An asymmetric semi-circular formed plate
presses the tubing against the rollers.
The correct pressure is automatically set by a
ball and spring construction when the door is
closed.
Pump tubing
The pump is delivered with 2.1 i.d.
silicone pump tubing, enabling a flow rate up
to 5 ml/min.
56-3000-47_AD.qxd 1998-10-21 14:17 Sida 4 (1,1)
