Siemens KION Service Manual page 28

Description of functions
Inspiratory Fresh Gas Valve with PC 1751 Step Motor:
The I F
NSPIRATORY RESH
motor with a special shape slotted cam mounted on
the motor shaft.
The gas flows through the fresh gas valve tube
(silicone rubber) that is a part of the inspiratory fresh
gas channel. The gas flow through the valve tube is
then regulated by a movable lever arm that squeezes
the valve tube against a fixed arm. This movable arm
is attached to the cam and transfers the step motors
rotation to a controlled opening position of the valve
tube.
The change in flow through the valve tube is micro-
step controlled by the step motor. The step motor is
3
controlled by PC 1751 that is a part of the step motor
assembly.
PC 1751 S M
TEP OTOR
two photo detectors. When the step motor reaches
either end position of the cam slot, the light beam
between the LED and the corresponding photo
detector is interrupted by a cam screen. The cam
screen is a part of the slotted cam mounted on the
motor shaft. This will generate an end position signal
from PC 1751.
The position of the LEDs / detectors in relation to the
cam screen is very important. If a LED / detector gets
out of position, or if they fail, this will cause the step
motor to "rattle" because end positions are not
properly indicated.
When power supply to the I
V is switched off (or if the power supply fails),
ALVE
the step motor will always end up with the
inspiratory valve in fully opened position.
The fresh gas valve tube must be replaced during the
"Six months maintenance" and the "Twelve months
maintenance".
3 - 10
G V is operated by a step
AS ALVE
is equipped with two LEDs and
F G
NSPIRATORY RESH
7. PEEP valve
The expiratory gas flow is regulated by the PEEP
V . This valve also regulates PEEP pressure if set
ALVE
on the C
ONTROL
The PEEP V
ALVE
magnet acting on a lever arm which squeezes the
expiratory valve tube (silicone rubber) against a fixed
arm. The more the magnet is activated, the more the
valve will move towards the closing position.
When power supply to the magnet is switched off,
the valve will be fully opened because of the spring.
This ensures that the patient always can exhale
through the ventilator at a power failure.
The PEEP valve is controlled by CON. At a PEEP
setting, information from the PEEP pressure trans-
ducer is used to regulate the valve position during
expiration.
The PEEP valve tube must be replaced during the
"Six months maintenance" and the "Twelve months
maintenance".
AS
Siemens-Elema AB
P .
ANEL
comprises a spring loaded pull
E382 E392E 061 01 02 02
KION / KION-i