Tokyo Boeki Labmax 240, Service Manual

Page: 92 / 178

3‑46
3.11.2. Function and Action
1. Function
This station is used for removal of reaction liquid after measurement, reaction
cuvette washing, and injection and removal of refined water for water blank
measurement.
Washing solution is heated to 37 Celsius degrees by pre-heater (WSH) and
dispensed into reaction cuvettes from washing solution dispensation nozzle.
The types of washing solution dispended and the amount are as follows.
1. Alkaline washing solution : 700 micro-liter
2. Acidic washing solution : 700 micro-liter
3. De-ionized water : 700 micro-liter X 5
Washing solution, which is dispensed into reaction cuvettes, is aspirated and
removed by aspiration nozzle.
And at the end, water droplets on the inside wall of cuvettes are aspirated and
removed by dry nozzle tip.
2. Action (Refer to “ASSY-13” for assembly drawing.)
When stepping motor (12) rotates counterclockwise, spline shaft (11) fixed to
timing belt (18) goes up and nozzle base (2) also goes up.
Timing belt (18) has a shade pin which shades home position sensor (13) light at
home position. This detects home position at initialization.
- Home position is at the top position.
At descent, stepping motor (12) rotates clockwise by the set numbers of pulse, and
nozzle base (2) goes down by this rotation.
The sensor is fixed for detecting the lower limit.
At descent, nozzle base goes down 1 mm lower than the distance between
aspiration nozzle and the bottom of reaction cuvette, and this excess is
absorbed by spring (6) for strict adhesion of the tip of nozzle and the bottom of
reaction cuvette.
Note The direction of motor rotation is shown when seen from the motor shaft
side.
In measurement, if nozzle base will not be at the home position within the fixed
time, system gives an alarm and emergency stop.