Brother NV4000D Service Manual page 20

Outline of Mechanism Operation of other electronic components
Start/Stop (SS) Switch . . . . . . . . . . . . . . . . . Switch for starting and stopping the sewing machine. The
Reverse switch . . . . . . . . . . . . . . . . . . . . . . . This switch is for backtracking or ending a seam. If the switch is
Raise needle switch . . . . . . . . . . . . . . . . . . . This switch toggles the needle between the up and down
Cut thread switch . . . . . . . . . . . . . . . . . . . . . This switch is for cutting the thread. If the switch is pressed, the
Needle Thread Switch . . . . . . . . . . . . . . . . . This switch is used to thread a needle automatically. Pressing
Raise Presser Switch . . . . . . . . . . . . . . . . . . This switch toggles the presser foot between the up and down
Touch Panel . . . . . . . . . . . . . . . . . . . . . . . . . Used to select pattern and input test mode number required for
Speed Control Lever. . . . . . . . . . . . . . . . . . . This lever detects for the speed of sewing.
BH (buttonhole) switch . . . . . . . . . . . . . . . . This switch is for detecting the forward and rear ends of the
BH (button hole) lever switch . . . . . . . . . . . This switch detects whether the BH lever is up or down.
NP sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . This sensor detects the drive timing for the pulse motor for the
Speed sensor. . . . . . . . . . . . . . . . . . . . . . . . . This sensor detects the rotational speed of the main motor. It
Cloth Thickness Sensor . . . . . . . . . . . . . . . . This sensor detects the thickness of cloth.
Knee Lifter Sensor . . . . . . . . . . . . . . . . . . . . This sensor detects the amount of operation of knee lifter.
1 - 6
machine operates at a slow speed while the switch is being held
down.
pushed, it makes three to four stitches in that place and stops
automatically. If the switch is held down, it sews at a slow speed
in the reverse direction as long as the switch is held.
positions.
thread is cut regardless of the position of the needle, and the
machine stops with the needle up.
this switch moves the needle bar to the thread guide position,
and pressing it again thread the needle and then returns the
needle bar to its original position.
positions.
sewing by simply touching the display on the panel. This
simplifies the oparation for selecting the desired pattern and
number.
button hole according to the BH presser and lever.
vertical stop position for the needle. It detects the upper shaft
angle of rotation using a shutter attached to the upper shaft and
an opitical sensor.
detects the upper shaft rotational speed using a shutter attached
to the upper shaft and an optical sensor.