Covidien Puritan Bennett 700 Series, Service Manual

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Theory of operation
Puritan Bennett™ 700 Series Ventilator System Service Manual 10070389 Rev. A 2-5
Table 2-1 provides some pertinent specifications and other data for the ventilator’s
pneumatic components.
Table 2-1: Pneumatic component data
Component Data
Check valve, air intake,
inlet Opens to draw in room air. Closes during oxygen delivery to reduce
noise.
Check valve, air intake
pressure relief Remains closed during normal operation. Opens at or below
5 cmH
2
O to prevent excess pressure in the intake duct.
Check valve, cylinder inlet Opens during piston retraction to draw in room air and/or oxygen
Check valve, cylinder outlet Opens to deliver mixed gas to the patient
Check valve, exhalation Opens during exhalation to permit exhaled gas into the exhalation
system. Prevents rebreathing.
Collector vial Collects moisture in the exhaled gas to keep water from occluding
the expiratory filter or entering the exhalation system.
Exhalation valve Piloted by exhalation solenoid. Opened during exhalation (as
required to maintain PEEP/CPAP). Closed during inspiration.
Filter, air intake ≥ 5
μ
m retention
Filter, expiratory > 0.3
μ
m nominal (and larger) retention at flow of 100 L/min
Filter, inspiratory (main
flow) > 0.3
μ
m nominal (and larger) retention at flow of 100 L/min
Filter, PEEP reservoir > 0.3
μ
m nominal (and larger) retention at a flow of 10 L/min
Fitting, oxygen (source) DISS (diameter index system standard) male. DISS female and male,
NIST (non-interchangeable screw thread), Air Liquide™*, Australian
type, and Dräger™* oxygen hose kits available, using adapters as
necessary.
Heater assembly,
exhalation Two 10 W heaters that maintain temperature of exhalation assembly
walls above condensation point
Piston/cylinder assembly
(includes piston/cylinder,
motor/encoder, and
optoswitches) Includes a brushless DC motor. Can deliver up to 2 L nominal.
Clearance of 50
μ
m (0.002 in.) between piston and cylinder wall.
Pump, PEEP Supplies PEEP pilot pressure of 0 to 25 cmH
2
O
Regulator, oxygen Output of 33
±
5 psi (227.46
±
34.48 kPa) throughout supply pressure
range of 40 to 90 psi (275 to 620 kPa) (no flow). Includes internal
filter (5
μ
m retention) and outlet filter (> 30
μ
m retention). Maximum
3 L/min bleed.
Sensor, exhalation flow A mesh screen with pressure taps on both sides. Pressure drop across
screen monitored by a differential pressure transducer and used to
determine flow.
Sensor, oxygen Measures percentage of oxygen in inspired gas (based on partial
pressure of oxygen). Range: 18 to 103% oxygen.