Terumo BCT Trima Accel, Руководство по обслуживанию

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Table 2-7: Centrifuge drive assembly components
Component Function
1 Gear assembly
The gear assembly allows the filler to spin at the commanded speed
and the centrifuge arm to spin at half the commanded speed. This
speed difference, combined with other aspects of the system's
design, prevents the centrifuge loop from twisting.
2 Centrifuge motor
The centrifuge motor runs the centrifuge. The motor is a three-phase,
brushless, DC motor rated at ¼ horsepower. The three phases are in a
wye configuration. Two legs of the wye are alternately energized (one
leg attached to V+ and the other to ground) to achieve rotation. Each
set of legs must be energized twice in sequence before one centrifuge
revolution is complete.
3 Centrifuge Hall-effect sensors
Three centrifuge Hall-effect sensors mounted inside the motor casing
sense the speed of the motor shaft. These sensors send a feedback
signal to the control and safety/ultrasonics CCAs to regulate
centrifuge speed. A quick-disconnect connector is used to facilitate
the removal and replacement of the centrifuge motor and gear train.
Another cable carries the drive signals generated by the centrifuge
motor controller to the centrifuge motor and connects at the rear of
the e-box.
4 Cooling fan The fan cools the centrifuge motor and geartrain. The 24 V DC fan has
a built-in Hall-effect sensor to detect fan operation.
Centrifuge Motor Controller
The centrifuge motor controller provides power to the three-phase centrifuge motor.
The control computer calculates the necessary drive for the centrifuge motor (based on algorithms) and
converts this drive signal to an analog voltage. The voltage is then amplified and sent to the centrifuge
motor controller. The motor controller controls the timing for the phasing of the three-phase centrifuge
motor. It uses feedback from the three Hall-effect sensors mounted inside the centrifuge motor to
determine the phasing sequence and timing. Both the safety computer and the control computer also
monitor the Hall-effect sensor signals to ensure that no sensor has failed. If a sensor has failed, a
centrifuge hardware failure alarm generates. When the centrifuge stops, due to either a command or an
alarm condition, the control system and the safety system can command the motor controller to brake
the centrifuge motor.
Centrifuge System
Trima Accel
®
Automated Blood Collection System • Service Manual 2-23