Singer NP050101 User manual

SINGER
INDUSTRIAL PRODUCTS
SERVICE MANUAL
for the
SINGER
Needle Positioner and Underbed Thread Trimmer
Catalog Numbers NP050101 and NP050103
I. —
Fordetails, call your Industrial Sales Office, or writeThe Singer Company,
Industrial Products Division,30 Rockefeller Plaza, New York, N.Y. 10020
THE SINGER COMPANY
INDUSTRIAL PRODUCTS DIVISION
'A Trade Mark ofThe Singer Company
Copyright ©1967 by The Singer Company
All Rights Reserved Throughout the World
Printed in U.S.A.
From the library of: Superior Sewing Machine & Supply LLC

TABLE OF CONTENTS
Paragraph Title Page
SECTION I - GENERAL INFORMATION
1-1 PURPOSE 1
1-2 FEATURES 2
1-3 BASIC COMPONENTS 2
SECTION II - INSTALLATION
2-1 GENERAL INFORMATION 3
2-2 PREPARATION OF SEWING TABLE 3
2-3 POWER TRANSMITTER 3
2-4 OPERATING SWITCHES 4
2-5 SEWING HEAD 10
2-6 COMMUTATOR SENSOR 10
2-7 POSITIONER CONTROL CONSOLE 11
2-8 TRIMMER PACK ASSEMBLY. 13
2-9 T RIMMER SOLENOID ASSEMBLY 16
2-10 THREAD WIPER 19
SECTION III - OPERATION
3-1 GENERAL INFORMATION 20
3-2 PRE-OPERATING CHECKS 20
3-3 OPERATION 20
SECTION IV - SERVICING AND ADJUSTMENTS
4-1 GENERAL INFORMATION 22
4-2 CLEANING INSTRUCTIONS 22
SECTION V - TROUBLESHOOTING
5-1 GENERAL INFORMATION 24
5-2 Needle Not Positioning Properly 24
5-3
Faulty Trimming or Double Triggering of Solenoid Assembly ... 24
5-4 Bobbin Thread Cut Too Short 24
5-5 Needle Thread Cut Too Short 25
5-6 Needle Thread Pulls Out of Needle 25
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LIST OF ILLUSTRATIONS
Figure Title Page
1 S inger Needle Positioner and Underbed Trimmer Equipped
Sewing Machine 1
2 Sewing Table Top 4
3 Operating Switches 5
4 Heel Switch Installation 6
5Foot Trim Switch Installation.• 7
6 Knee Trim Switch Installation 8
7Slo-Sew Switch 8
8Operating Switches Assembly and Wiring Data 9
9 Commutator Sensor 11
lOA &B Positioner Control Console 12
1lA &B
Trim Pack Thread Picker Installation 14
nC Trim Pack Thread Picker Installation 15
IID Thread Picker Adjustment 15
12 Setting of Trimmer Knife 16
13 Trimmer Solenoid Assembly 17
14A &B Trimmer Solenoid Adjustments Procedure 18
15 Thread Wiper J9
16 Operating Controls
21
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Catalog No, NP050101 refers to Machine Nos, 281-41 and 281-43.
Catalog No. NP050103 refers to Machine No. 281-61.
SECTION 1 - GENERAL INFORMATION
PURPOSE
The Underbed Trimmer and Needle Positioner, figure 1, has been developed by
The Singer Co. to Increase the efficiency, speed and accuracy ofa sewing machine
operator working on apparel manufacturing. The operator need not position the
needle and cut top and bottom threads by hand. Instead the operator merely
touches a knee switch or a foot treadle and the positioner/trimmer does this auto
matically, thus accomplishing automatic positioning, and trimming of both top and
bottom threads of material being sewn.
TRIM PACK THREAD PICKER
ASSEMBLY (HIDDEN)
SOLENOID
PACKAGE
y
COMMUTATOR
SFWCJOR
POSITIONER
CONSOLE
Figure 1 .. . .SINGER Needle Positioner and Underbed Trimmer Equipped Sewing Machine
From the library of: Superior Sewing Machine & Supply LLC

1-2. FEATURES
The Underbed Trimmer and Needle Positioner has the following advantages:
a. INCREASED PRODUCTION .... Increased output because needle
positioning and underbed trimming of top and bottom thread is •
fast and automatic.
b. FLEXIBILITY. .. .When Positioner/Trimmer is not required,
the unit con be switched off and the sewing machine can
be operated conventionally, since the unit does not require
special fittings.
c. RELIABILITY. ... Exclusive solid-state electronic controls,
and quality components coupled with outstanding mechanical
design and construction throughout, provide the utmost in
reliability.
d. SIMPLICITY OF OPERATION... .Operators con be trained
quickly and easily. Response time is fast, and controls are
designed for fast easy operation. The unit can position one
stitch at a time - to "slowsew" (available as an option).
Operator may select either Needle Position Down - or
Needle Position Up and Trim.
e. EASE OF MAINTENANCE... .Maintenance and periodic
inspection of the Positioner/Trimmer can be accomplished
very easily. The electronic portion of the Positioner/
Trimmer is incorporated into two compact, rugged printed
circuit boards.
1-3. BASIC COMPONENTS
The Underbed Trimmer and Positioner consists of the following subossemblies:
a. Trimmer Assembly
b. Trimmer Solenoid Assembly
c. Harness Assembly consisting of
(1) Heel Switch
(2) Trimmer Switch (foot or knee switch)
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(3) Slow Sew Switch (optional)
d. Needle Positioner Assembly
e. Commutator Sensor Assembly
f. Thread Wiper Assembly
SECTION n - INSTALLATION
2-1. GENERAL INFORMATION
This Section will describe the physical installation of the subossemblies that make
up the complete Underbed Trimmer and Positioner.
CAUTION :
This machine should operate from
110-115 volt source only.
Electricity should be shut off during
installation until instructed otherwise.
NOfE
Do not attempt to operate from one leg of a 220 volt line.
2-2. PREPARATION OF SEWING TABLE (See Figure 2)
Package table will have the cutout for double v-belt pulley, the large holefor
the needle positioner leads and the elongated hole for the thread wiper cable and
lamp cord.
NOTE
For field installation, dimensions for cutout and holes
are shown in Figure 2.
2-3. CLUTCH MOTOR
If the Underbed Trimmer and Positioner assemblies are to be added to a standard
sewing machine and table, it will be necessary to remove the motor and mount
it exactly 1 inch (1") to the left of the standard position.
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MACH NE
3-1/4
1-1/2 DIA. HOLE
RIGHT SIDE OF TABLE
3/8 MIN
BELT SLOT
8-15/16
4-7/8
TABLE
5-13/16 I
(3) (.228 DIA. HOLES)
NO. I DRILL
I" DEEP MIN.
Figure 2,...Sewing Table Top
2-4. OPERATING SWITCHES
All operofing switches ore shown in the illustration. Figure 3. It should be noted
that the sewing machine table has the Pitman rods, basic foot treadle and
linkages to the power transmitter, in place.
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KNEE
TRIMMER
SWITCH
TREADLE
SWITCH
TRIMMER
FOOT SWITCH
SLOW-SEW
SWITCH
TREADLE
Figure 3... .OperaHng Switches
2-4-1. HEEL SWITCH. . .The purpose of the heel switch is to activate the needle
positioner. Since the heel switch is
mounted on the Pitman rod, when the
treadle is firmly heeled, the heel switch is activated. If the heel switch has
not been mounted on the Pitman rod, refer to Figure 4 for its proper position
and proceed as follows:
a. Remove clamp from standard Pitman rods. Pitman rod should
be mounted at extreme outside position of power transmitter
b. Install heel switch as shown in Figure 4.
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2-4-2. TRIM SWITCH (See Figure 3)
The Trim Switch isa universal type that can be used either for knee operation,
mounted under table or as a foot switch when slipped on treadle rod to left of
treadle.
a. Foot Trim Switch - mounted to the left of the treadle. When
treadle is firmly heeled and the foot trim switch is depressed,
the machine will position up and trim.
b. Knee Trim Switch - mounted under the table. When activated
by the knee, the machine will position up and trim.
If the trim switch has not been installed on the sewing table proceed as follows:
PITMAN ROD
(TO MOTOR)
SCREW ADJUST
PITMAN ROD
(TO TREADLE)
s
Figure 4... .Heel Switch Installation
"a" set screw
COLLAR
HEEL PRESSURE
adjust"
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2-4-2-1. Foof Type (See Figure 5)
(a)
Loosen clamp screws for freadle support rod and
slide to right.
(b) Slip foot switch over rod and locate several inches to
left of treadle to suit operator.
2-4-2-2. Knee Type (See Figure 6)
(a) Locate and pilot drill holes for wood screws according
to location shown in Figure 6.
(b) Mount switch bracket with wood screws, "B".
(c) By loosening clomp screws "A", the switch may be
moved to the left or right or rotated forward or bock
to suit operator. Tighten clomp screws.
(d) By loosening screws "C", the knee switch may be
moved up or down to suit operator. Tighten clamp
screws.
2-4-3. The Slo-Sew Switch is physically the same as the trim switch and mounts
on treadle rod to the right of the treadle. (See Figure 7)
TRIMMER SWITCH
TREADLE
Figure 5... .Foot Trim Switch Installation
From the library of: Superior Sewing Machine & Supply LLC