Operation Of Each Part - Brother LX-300 Service Manual

5.2 Operation of Each Part

This unit is operated by three 24 V stepping motors and one DC motor (for the X-cutter
assy). The operation of each motor shown in Fig. 5.1-1 is described below.
S
LF motor
This motor is used to feed the document and film and to eject the film.
The motor is a 49 mm dia. 48-step PM stepping motor. It is set to feed the
document and film approximately 1 mm per 19 steps using 2-2 bipolar drive.
S
SG Motor
This motor conducts trimming operation, drives the Y-cutter vertical movement, and
switches between document feed, film feed, and film ejection.
The motor is a 42 mm dia. 48-step PM stepping motor. A single trimming operation
is completed by 266 steps in the reverse direction from the home position, then 266
steps in the forward direction. Selection between document feed, film feed, and film
ejection occurs within 515 steps from the home position. The Y-cutter vertical
movement requires approximately 407 steps.
S
Y-CA motor
This motor moves the Y-carriage to the edge of the document.
The Y-cutter and paper size sensor PCB are mounted on the Y-carriage. The motor
is a 24 mm dia. 24-step PM stepping motor. It is set to feed the Y-carriage
approximately 1 mm per 5 steps using 2-2 phase drive.
S
X-cutter (DC motor)
This 24V DC motor and two cutter position detector switches are mounted on the X-
cutter. The direction of cutter movement is determined by the direction of current
flow in the DC motor.
5-3