Philips Respironics V60, Руководство по обслуживанию

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1049766 Rev A V60 Ventilator Service Manual
3-1
Chapter 3. Theory of Operation
The V60 ventilator is a microprocessor-controlled gas flow control and
monitoring system that can deliver air and oxygen to augment or replace the
work normally performed by the patient’s respiratory system. The ventilator
uses electromechanical control circuits, flow and pressure monitors, and
software programs to deliver pressure controlled breaths.
The ventilator includes a user interface (UI), internal blower, and gas delivery
subsystem (GDS) that mixes air and oxygen. The ventilator can operate from a
40 to 87 psig (276 to 600 kPa) medical grade oxygen source for enriched
oxygen operation. The internal power supply that can operate from mains (100
to 240 V AC 50/60 Hz) or internal battery (14.4 V DC) power. The ventilator
also includes several communications interfaces.
Schematic diagrams of the V60 ventilator are available upon request.
3.1 Pneumatics
The pneumatic subsystem delivers and monitors pressurized gas to the patient
in response to commands from the CPU subsystem. The pneumatic subsystem
includes the:
• Manifold
• Blower
• Oxygen solenoid valve
• Air and oxygen flow sensors
• Pressure transducers
• Solenoid valves
• Motor controller (MC) PCBA
• Data acquisition (DA) PCBA
The ventilator uses ambient air and high-pressure oxygen. Air enters through
an inlet filter. Oxygen enters though a high-pressure inlet, and a proportional
valve provides the operator-set concentration. The system mixes the air and
oxygen, pressurizes it in the blower, and then regulates it to the user-set
pressure. To do this, the ventilator compares the proximal (patient) pressure
measurement with the ventilator outlet (machine) pressure, and adjusts the
machine pressure to compensate for the pressure drop across the inspiratory
filter, patient circuit, and humidifier. This helps ensure accurate and
responsive pressure delivery and leak compensation.
The ventilator delivers gas to the patient through a main flow (inspiratory)
bacteria filter, a single-limb patient breathing circuit, a humidification device
(optional), and a patient interface such as a mask or ET tube. A pressure tap