Brother PE-150 User manual

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
2. 1999.

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• This service manual has been compiled for explaining the repair procedures for the PE-150 HOME
EMBROIDERY MACHINES.
• Use this service manual in conjunction with the Part List when you make a repair.
• This machine is manufactured based on product specifications which are current at the time of printing of this
manual. However, specifications are subject to change for improvement without notice, so contract the
manufacturer or your local sales agent for information regarding such changes.
Brother Industries, Ltd.
Nagoya, Japan
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I. PRINCIPAL MECHANISMS....................................................................................2
II.DISASSEMBLY AND REASSEMBLY PROCEDURES..........................................8
III.ADJUSTMENT STANDARDS AND ADJUSTMENT PROCEDURES
FOR MECHANICAL PARTS.................................................................................13
IV.PROBLEM DIAGNOSIS PROCEDURES FOR THE ELECTRONIC
SYSTEMS.............................................................................................................34

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Most processes in the manufacturer of LSI devices such as microprocessors involve MOS (metal oxide
semiconductor) technology. It is thus necessary to take extreme care to prevent erasure or other damage caused
by static electricity during the use and manufacture of products using such LSI devices.
This embroidery machine is manufactured and assembled under a strictly controlled system preventing such
damage.
Similar care is also required during the service and maintenance of this product.
Please be sure to observe the following.
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1. Always wear rubber gloves when handling the circuit boards. Never touch metal components with your bare
hands.
2. Ground your body to prevent static charge build-up.
3. When storing and shipping circuit boards, always wrap the circuit board in the specified aluminum foil
wrapper or equivalent static-prevention bag, and protect the circuit board from physical shock.
4. During adjustment and repair, do not touch or damage the circuit board with a screwdriver or other tool, and
do not touch the circuit-side of the board.
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• The following symbols are used in this service manual.

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1.MECHANICAL CHART....................................................................................3
2.POWER TRANSMISSION ASSEMBLY (VERTICAL NEEDLE BAR
MOVEMENT,THREAD TAKE-UP MOVEMENT AND ROTARY
HOOK MOVEMENT)........................................................................................4
3.ELECTRONIC PARTSLAYOUT CHART........................................................5
4.CONTROL SYSTEM BLOCK DIAGRAM........................................................5
5.MAIN MOTOR CONTROL SYSTEM................................................................6
6.PATTERN GENERATOR.................................................................................6
7.OTHER ELECTRONIC COMPONENT FUNCTIONS......................................7

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1. MECHANICAL CHART

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2. POWER TRANSMISSION ASSEMBLY (VERTICAL NEEDLE BAR MOVEMENT,
THREAD TAKE-UP MOVEMENT AND ROTARY HOOK MOVEMENT)
Main motor
T pulley
Hand wheelUpper shaft gearMain shaft
Thread take-up
Cou
nt
e
r w
e
i
g
h
t
Timing belt
Rotary hook shaft pulley
Rotary hook
Needle
Needle bar
Needle bar clamp
Needle bar crank
r
od
Needle bar crank
Thread take-up
lever
Vertical shaft pulley
Vertical shaft
Vertical shaft gear

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3. ELECTRONIC PARTS LAYOUT CHART
4. CONTROL SYSTEM BLOCK DIAGRAM

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5. MAIN MOTOR CONTROL SYSTEM
The main motor must operate at a constant speed regardless of load fluctuations, temperature fluctuations, or
other changes in operating conditions. The main motor is therefore driven by means of PWM (Pulse Width
Modulation) control.
6. PATTERN GENERATOR
This embroidery machine stores the pattern data to memory, and drives the embroidery frame using the X and Y
pulse motors to produce the patterns. It is therefore possible to increase the number of stored patterns and the
total number of stitches by simply increasing the storage capacity of the embroidery machine.
Good positioning and response speed are also required of the pulse motors used in this machine because the
embroidery frame must be moved and stopped in a precise position while the need is up. A PM-type pulse motor
is therefore used with a simple open loop circuit configuration to drive the embroidery frame in this machine.
Pattern generator control block diagram

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7. OTHER ELECTRONIC COMPONENT FUNCTIONS
Start/stop switch ...............................Used to start and stop machine operation. When starting, the embroidery
machine operates at low speed as long as the switch is pressed. The need
will stop in the up position if pressed immediately after the "Raise needle"
error message is displayed.
Touch panel .......................................Used to enter the pattern selection and other sewing conditions. The touch
panel replaces the conventional switches, and makes pattern selection
possible by simply touching the panel.
Presser switch...................................Detects whether the presser lever is up or down.
Rotation sensor.................................Detects the drive timing of the embroidery frame drive pulse motor and the
tension release solenoid and detects the vertical position of the needle. Also
detects the turning angle of the upper shaft by means of a photointerruptor
and shutter installed on the upper shaft.
Speed sensor.....................................Detects the operating speed of the main motor by means of a photointerruptor
and shutter installed on the upper shaft.
Bobbin winder switch.......................Detects whether the bobbin winder has been set when starting bobbin
winding.
Transformer .......................................Used for pulse motor and solenoid drive, sew light power and for the
electronic circuit power supply.
Work light...........................................Uses an 8-V, 2.4-W bulb to illuminate the presser foot area.
Tension release solenoid .................Opens the tension disc to prevent the needle thread from becoming
tangled when forming long crossover threads.

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1.DISASSEMBLY AND REASSEMBLY PROCEDURES FOR EXTERNAL
PARTS AND MAJOR COMPONENTS........................................................... 9
2.SECURING THE LEADS................................................................................12

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1. DISASSEMBLY AND REASSEMBLY PROCEDURES FOR EXTERNAL
PARTS AND MAJOR COMPONENTS
1. Raise the presser foot lever, remove the screw, and then remove the face plate from the left side.
2. Remove the two screws of the needle plate and then lift out the needle plate.
3. Loosen the screw of the X carriage cover and then remove the X carriage cover.
4. Remove the four screws of the bottom plate and the two screws of the cover, and then remove the bottom
plate.
5. Remove the four screws of the rear cover and then remove the rear cover.
6. Remove the main cover to the left side.
7. Remove the four screws of the front cover. Then remove the front cover from the lower section of the thread
path cover and the part around the tension control dial in that order, and then disconnect the three electrical
connectors to remove the front cover.
8. Remove the belt cover.

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9. Disconnect the 13 electrical connectors, remove the two screws, and then remove the main PC board.
10. Remove the screws and then remove the embroidery presser foot and needle.
11. Remove the two screws of the thread path assembly, remove the tension spring, and then remove the thread
path assembly.
12. Remove the two screws and then remove the solenoid holder assembly.
13. Remove the screw of the main motor cover and then remove the main motor cover. (220 to 240 V models
only)
14. Remove the two screws of the motor holder, disconnect the electrical connectors and then remove the motor
holder assembly.
15. Remove the screws and then remove the shutter cover.
16. Remove the screw of the back cover.
17. Remove the three screws of the fixation unit.
18. Remove the two screws of the upper shaft bushing fixation and then remove the upper shaft bushing
fixation.
19. Remove the main shaft assembly and presser unit.
20. Remove the two screws and then remove the handle.
21. Remove the two screws and then remove the bobbin winder holder assembly.

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22. Remove the two screws of the bushing fixation and then remove the vertical shaft.
23. Remove the three screws of the rotary hook shaft frame assembly and then remove the rotary hook unit.
24. Remove the screw and then remove the circuit board mounting plate.
25. Remove the three screws and then remove the power supply unit cover.
26. Remove the screw and then remove the switch holder.
27. Remove the three screws and then remove the power supply unit.
28. Remove the four screws and then remove the main frame.
29. Remove the two screws and then remove the inlet assembly.

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2. SECURING THE LEADS
Please note the following.
1. Be sure the LCD module leads are not pinched by the handle when passed through the shutter cover and
the handle is lifted.
2. The sew light leads from the power supply PC board extend to the front from the right side of the main PC
board amount of the bobbin winder holder.
3. The leads coming from the power supply PC board pass under the cord holder of the power supply unit and
out to the front.
4. (For 220 – 240 V specifications only)
Pass the cord for the main motor under the main motor cover so that it will not directly touch the main motor.

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1.TEST MODE SETTING METHOD..................................................................14
2.TENSION OF MOTOR DRIVE BELT AND ROTARY HOOK SHAFT BELT.15
3.POSITION OF SENSOR SHUTTER..............................................................16
4.ADJUSTMENT OF NEEDLE DROP POINT..................................................17
5.CLEARANCE BETWEEN NEEDLE AND ROTARY HOOK POINT
AND LOOP LIFT............................................................................................18
6.HEIGHT OF NEEDLE BAR............................................................................19
7.ADJUSTMENT OF THREAD TAKE-UP SPRING
(ADJUSTMENT OF THREAD BREAKAGE SHUTTER)................................20
8.ADJUSTMENT OF BOBBIN WINDING
(ADJUSTMENT OF BOBBIN WINDER SWITCH).........................................21
9.POSITION OF INNER ROTARY HOOK BRACKET......................................22
10.ADJUSTMENT OF INNER ROTARY HOOK TENSION................................23
11.ADJUSTMENT OF TREAD TENSION DIAL..................................................24
12.POSITION OF TENSION RELEASE SOLENOID..........................................25
13.NEEDLE THREADER....................................................................................26
14.NEEDLE THREADER(ADJUSTMENT OF NEEDLE THREADER)..............27
15.NEEDLE THREADER (REPLACINGTHE HOOK).......................................28
16.X-Y CARRIAGE (XTIMING BELT TENSION)...............................................29
17.X-Y CARRIAGE (YTIMING BELT TENSION)...............................................30
18.X-Y CARRIAGE (DRIVE GEAR ADJUSTMENT)...........................................31
19.X-Y CARRIAGE (XCARRIAGE POSITION)..................................................32
20.ADJUSTMENT OF INNER ROTARY HOOK HOLDER AND
LOWER THREAD GUIDEPLATE.................................................................33

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1. TEST MODE SETTING METHOD
STANDARD
To enter the test mode, press and hold down both the left and right sides of the CHARACTER PATTERNS button
while simultaneously turning on the power switch (Fig. 1).
The test mode numbers will be displayed in the touch panel (Fig. 2).
Select the desired test mode by pressing the corresponding number.
Adjustment item Test mode No.
Thread take-up spring adjustment 26
All other test mode numbers are reserved and are not used for adjustment.
[Fig. 1]
[Fig. 2]

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2. TENSION OF MOTOR DRIVE BELT AND ROTARY HOOK SHAFT BELT
STANDARD
Motor belt tension: The belt should move in by 5 - 7 mm when a force of approximately 2 N (200 g) is applied
midway between the drive pulley and motor shaft. Rotary hook shaft belt tension: The belt should move in by 6 - 8
mm when a force of approximately 2 N (200 g) is applied midway between the rotary hook shaft pulley and
vertical shaft pulley.
ADJUSTMENT
1. Loosen the two screws of the motor holder.
2. Move the motor holder to adjust the belt deflection to 5 - 7 mm.
3. Tighten the two screws of the motor holder.
4. Slightly loosen the screw of the eccentric shaft.
5. Turn the eccentric shaft right or left to adjust the belt deflection to 6 - 8 mm.
6. Tighten the screw of the eccentric shaft.

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3. POSITION OF SENSOR SHUTTER
STANDARD
When the needle bar is at its highest position, the rotary shutter should be positioned so that the screw is facing
toward the front of the machine.
ADJUSTMENT
1. Turn the hand wheel to raise the needle bar to its highest position.
2. Loosen the screw of the rotary shutter.
3. Turn the screw of the rotary shutter toward the front.
4. Tighten the screw of the rotary shutter.
NOTE : Make sure the side of the rotary shutter does not contact the photointerrupter. Turn the hand wheel
by hand to check.

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4. ADJUSTMENT OF NEEDLE DROP POINT
STANDARD
The needle should enter 0.9 mm inward from the left end of the needle hole in the needle plate when the hand
wheel is turned.
ADJUSTMENT
1. Turn the hand wheel by hand and observe the position of the needle in the needle hole.
2. Loosen the screw and the set screw of the presser unit.
3. Move the presser unit right or left so that the needle point locates 0.9 mm inward from the left end of the
needle hole.
4. Tighten the screw and the set screw of the presser unit.
5. Turn the hand wheel by hand and recheck the needle drop point.

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5. CLEARANCE BETWEEN NEEDLE AND ROTARY HOOK POINT AND LOOP LIFT
STANDARD
When the needle is raised 2.2 - 2.6 mm from its lowest position, the rotary hook point should be at the side of the
needle. The gap between the needle (75/11) and rotary hook point at this time should be less than 0.1 mm with
no contact between the rotary hook point and the needle.
ADJUSTMENT
* Remove the inner rotary hook before adjusting.
1. Loosen the two set screws of the rotary hook pulley.
2. Adjust so that the rotary hook should be at the side of the needle when the needle is raised 2.2 - 2.6 mm
from its lowest position.
3. Tighten the two set screws of the rotary hook pulley.
4. Loosen the screw.
5. Turn the set screw in or out so that the clearance between the needle and the rotary hook point is less than
0.1 mm.
6. Tighten the screw.