3-4
V60 Ventilator Service Manual
1049766 Rev A
Chapter 3: Theory of Operation
3.1.7
Manifold, Oxygen Inlet Filter, Filter Element
The
manifold
includes a connection for the oxygen inlet, allowing country-
specific oxygen connections to be attached to the manifold. The manifold
provides the pneumatic interfaces to the air inlet, oxygen inlet, blower inlet,
and proximal and machine pressure lines.
The
oxygen inlet filter
removes 5-micron particles from the oxygen gas supply.
A
40-micron sintered bronze
filter element
acts to reduce turbulence in the
oxygen flow. The 40-micron oxygen breather vent reduces noise in the oxygen
flow.
3.1.8
Oxygen Solenoid Valve
The
oxygen solenoid valve
and valve driver circuitry control the flow of oxygen
according to the set O
2
and flow. The oxygen solenoid valve is closed when
there is a loss of power or system reset.
3.1.9
Oxygen Flow Sensor
The
oxygen flow sensor
measures a subset (bypass flow) of the total flow.
These measurements are interpolated according to constants that are
calculated during GDS calibration. Together, the oxygen solenoid valve and
flow sensor provide closed-loop control for delivered oxygen flow.
3.1.10 Blower
The
blower
is controlled by the MC PCBA, and generates flow and pressure for
the system. The blower includes an impeller, housing, and a three-phase
brushless DC motor. The blower delivers a maximum pressure of less than 125
cmH
2
O in a dead-head condition, can accelerate from 10,000 to 22,500
revolutions per minute (RPM) in 120 msec from a nominal 5- to 25-cmH
2
O
pressure rise. Maximum motor speed is approximately 40,000 RPM. The
blower motor has internal Hall Effect sensors that are monitored by the MC
PCBA and measure impeller speed.
Manifold
Oxygen solenoid valve
Manifold
Oxygen flow
sensor
Blower
Manifold
Oxygen
inlet
filter
Oxygen
filter
element
Oxygen
breather
vent
