Mindray A7 Service Manual

A7™ Service Manual 046-006272-00 1 - 45
Theory of Operation The Breathing System
1.5.3 Automatic Mode, Expiration
When the Auto/Manual switch is set to Auto, the system closes the manual ventilation path. Drive-
gas flow stops and the exhaust valve opens. Exhaled gas flows from the patient, through the
expiratory check valve, and into the bellows.
Residual drive gas flows out of the bellows dome through the exhaust valve to the scavenging
system (AGSS).
If PEEP is selected, static pressure on the pilot port of the exhaust valve sets the PEEP level.
During exhalation, fresh gas flows backwards through the CO2 absorber into the expiratory limb,
downstream of the expiratory check valve.
FIGURE 1-52 Automatic Mode, Expiration Diagram
1.5.4 Manual Mode, Inspiration
When the Auto/Manual switch is set to Manual, the system closes the Auto ventilation path. Gas
flows from the breathing bag when compressed, through the CO2 absorber canister, into the
breathing circuit, and through the inspiratory check valve to the patient.
During inspiration, fresh gas flows from the machine into the inspiratory limb, upstream of the
inspiratory check valve.

Mindray A7 Specifications

General

Brand	Mindray
Model	A7
Category	Medical Equipment
Language	English