JUKI LBH-1790A Series User manual

LBH-1790A Series
Computer-controlled, High-speed, Buttonholing Machine
LBH-1790A
The thread tension and all drive mechanisms
are electronically controlled.
Series
LBH-1790AS
(Table stand is optionally available.)
The LBH-1790A Series follows
the world's highest sewing speed and
dry-head mechanism.

Auxiliary table
(standard accessory)
LED light
(Provided as standard)
17mm
by Digitization
Excellent operability by Digitization Excellent seam quality
Many functions of the pedal.
The machine is provided as standard with a newly-developed auto-lifter driven by a stepping motor. This helps reduce the operator's fatigue.
As for the pedal, one-pedal and two-pedal models can both be changed over and the intermediate stop, which facilitates positioning of the
sewing product, can be specified.
The work clamp foot lift can be set as desired. The reverse-rotation needle-up function offers a maximum work clamp foot lift of 17mm.
Higher productivity
Cycle sewing and continuous sewing.
All drive mechanisms are electronically controlled
Operator-friendly environment
The maximum sewing speed is 4,200 sti/min., and the jump speed
is 200 mm/s. The cycle time has been further reduced for continuous
sewing.
Electronic control of the material feed mechanism, needle feed
mechanism, needle thread trimming mechanism, bobbin thread
trimming mechanism, cloth trimming mechanism, presser lifter
mechanism and other mechanisms has been achieved.
All adjustment values are digitalized to enable the operator to set
and store those values on the operation panel.
Operation with reduced noise is ensured by the adoption of the
direct-drive motor.
The illuminance of the LED light is adjustable and is located on the
underside of the arm jaw. It is provided as standard for all models of
the LBH-1790A Series.
The sewing product can further be placed on the machine easily by
installing the auxiliary table (standard accessory). In addition, the
needle entry is located in the center of the bed, promising easier
positioning of the sewing product.
Twenty different programs can be registered, and as many as 15
different patterns can be stored in one program.
Cycle sewing
The machine is able to continuously sew two or more different
patterns without requiring the work clamp foot to be lifted. As may as
20 programs can be registered, and six different patterns can be
stored in one program. (Related parts need to be exchanged for
optional ones.)
Continuous sewing
JUKI's unique active tension (Electronic thread tension control system).
Basting stitchWithout basting stitch With basting stitch
(The state in which the material is stretched in
the lengthwise direction after buttonholing)
Finished state of
double stitching
State of firstround
stitch
Whip stitchingPurl stitching
Needle thread tension for sewing parallel and bartacking sections of buttonholes
can be separately controlled through the operation panel and stored in memory
according to various sewing conditions (e.g., type of thread, type of material and
sewing speed).
The basting stitch is effective on elastic materials such as knits.
Basting stitch: Since the needle thread is tucked in without fail, it will
never jut out of the buttonhole seams.
Basting stitch can be sewn by nine rounds.
The machine is able to change the needle thread tensions at the parallel and
bartacking sections of the buttonhole, to produce a beautiful buttonhole shape.
This capability helps greatly in preventing thread breakage.
Needle thread tension is activated at the beginning and end of sewing. This
prevents unthreading of the needle thread, and thread fraying that is likely to
occur at the beginning of sewing.
Thread tension for basting stitching can be specified separately.
(For a changeover between purl stitch
and whip stitch, threading of bobbin,
as well as the bobbin thread tension
need to be changed.)
For double stitching, the bartacking section
is skipped and only the parallel sections are
sewn twice. This prevents any excessively
tight finishes in the bartacking section of the
buttonhole.
First- and second-round stitches can be
sewn using different stitch widths.
The LBH-1790A Series follows the world's highest sewing speed and dry-head mechanism
of its predecessor model. In addition, this machine comes with the latest model
operation panel which is installed with a USB port.
Furthermore, all drive mechanisms have been digitalized to
manage each sewing pattern individually.
LBH-1790A Series
LBH-1790AS
Solenoid Needle thread tensioner
Explanation of pedal motion
Pedal motion
Initial position ②Intermediate position ①Maximum position ①Maximum position
Setting of
sewing product
Start of sewing
End of sewing
Pedal type
2-pedal 1-pedal 1-pedal
The right side pedal is depressed. The second step of the right side pedal The third step of the right side pedal
②Presser automatically goes up to
intermediate position.
①Presser automatically goes up to
maximum position.
①Presser automatically goes up to
maximum position.
Work clamp
position
Cloth
③
②
①
Sewing position
Intermediate position
Maximum position
(without intermediate position) (with intermediate position)
Presser goes up as high as the pedal
toe down amount of the left side
pedal. Presser comes down when the
left side pedal is depressed.
→③ Sewing position
The first step of the right side pedal
→③ Sewing position
The first step of the right side pedal
→② Intermediate position
The second step of the right side pedal
→③ Sewing position
Basting stitch mechanism is effective
for the production of beautiful buttonholes.
Sewing settings can be easily changed.
Thanks to the multiple knife-dropping function, it is no longer
required that the knife be changed at the time the buttonhole size is
changed. The number of knife dropping times can be automatically
set according to the buttonholing size in cases where the buttonhole
size is frequently changed for small-lot productions or during the
cycle sewing of buttonholes that are different in size.
The double-acting stepping motor type knife mechanism is free from
the faulty dropping/returning of the knife. In addition, the knife
pressure can be changed according to the material to be sewn.
The knife supports sewing lengths of 41mm at the maximum. In
addition, knife mechanisms for 70mm and 120mm are optionally
available.
The machine is equipped
with a multiple knife-dropping function.
Whip stitching󱽗Purl stitching Double stitching󱽗Single stitching

LBH-1795A
The machine eliminates oil stains on the sewing product.
Adjustment of the hook oil quantity
Computer-controlled, High-speed, Buttonholing Machine (120mm presser type)
120mm buttonhole
LBH-1795AS LBH-1795AS
Oil feeding hole
Hook oil quality
adjustment screw
Improved maintainability
It is able to store 99 different patterns in its memory, which can be selected as desired from the operation panel.
The machine is provided as standard with as many as
31 stitch patterns for buttonholing.
Square
1
Round
2
Radial square
3
Semilunar
11
Eyelet round
17
Semilunar
radial
25
Semilunar
round
26
Bartacking
27
Square radial
18
Square
semilunar
19
Square round
20
Radial
semilunar
23
Radial round
24
Round square
12
Semilunar
square
13
Eyelet
semilunar
16
Radial
4
Eyelet square
7
Eyelet radial
8
Radial straight
bartacking
5
Eyelet straight
bartacking
9
Eyelet taper
bartacking
10
Semilunar straight
bartacking
14
Square taper
bartacking
22
Bartacking,
center cut
30
Bartacking,
left cut
29
Bartacking,
right cut
28
Square straight
bartacking
21
Basting stitch
+ Knife
31
Semilunar taper
bartacking
15
Radial taper
bartacking
6
The memory storage capability of the main body of the sewing machine has been dramatically
enhanced. Now the USB-ready main body of the sewing machine uses many different kinds
of media. The main body of the sewing machine is provided as stanrard with a USB port. Now,
date can be input/output to/from various kinds of media (SD (Secure Digital Card), CF
(Compact Flash), etc.) by means of a USB thumb device and a card reader.
USB Port is provided as standard on the standard panel
All kinds of data can be entered on or selected from the operation panel.
The panel display supports 14 different languages.
Thanks to our advanced dry-head technology, no lubrication is required except for the hook section.
This eliminates oil stains on the sewing product.
Only a minute-quantity of clean oil is fed to the hook section from the
oil tank.
The oil tank is made of shatter proof material, thereby preventing
tank-related troubles such as breakage by some mishap.
The knife supports sewing lengths of 41mm at the maximum. Since the LBH-1795AS is provided as standard with the 120 mm presser, it is capable
of sewing 12-mm long buttonholes. The LBH-1795AS is capable of sewing long buttonholes such as belt holes in car seats. In addition, it is
applicable to the sewing of buttonholes in men's shirts (continuous sewing of two buttonholes and the use of two units of sewing machines), etc.
The upper limit of the adjustment of the presser foot
pressure has been expanded. The presser foot pressure is
now digitally controlled. As a result, the machine acquires
improved responsiveness to knit materials and car seats.
The newly installed "hook oil quality adjustment screw" can be
found by opening the hook lid cover. With this screw, the operator is
able to to adjust the oil quantity in the hook with ease.
Oil can be easily added to the hook oil quantity tank with an oiler.
The machine can be completely changed into a dry-head machine by replacing the hook with an optional non-lubricated hook.
(In this case, the maximum sewing speed will be 3,300sti/min)
Non-lubricated
section
(minute-quantity
lubrication)
Hook section
Hook
Oil tank
USB card reader
USB port
SD SM
mini
SD CF MS
STANDARD LIQUID CRYSTAL PANEL (NEW)
OPERATION PANEL

OPTION
Cloth cutting knife, Work clamp
SPECIFICATIONS
Throat plate
Designation Part No. Description Feature
400-06345
400-06349
137-29660
SS-8660612-TP (4 pcs.)
400-06340
SM-6040450-TP (3 pcs.)
145-23252
145-23401
145-23708
145-24102
400-08646
400-08658
400-06335
400-06339
400-06341
400-06342
SM-6050800-SP (2 pcs.)
SS-6060210-SP (2 pcs.)
G5001-198-0A0-A
400-05405
400-53150
SK-3452001-SE
GPK-510010B0
400-03493
RP hook (asm.)
RP bobbin case
Hook sleeve (asm.)
Screws
Work clamp arm spacer
Screws
Work clamp foot 70 (asm.)
Work clamp 70
Urethane work clamp 70 Selectable
Flat work clamp 70
Work clamp foot 120 (asm.)
Work clamp 120
Work clamp arm 120
Cloth feeding plate 120
Close cam 120
Lifting plate 120
Screws
Screws
Electric bobbin winder (asm.)
Power cord (asm.)
Tension controller (asm.)
Wood screws
Pedal switch (asm.)
Junction cable (asm.)
Non-lubricated hook
Exclusive to 70mm
Work clamp
(For sewing length
of 70 mm, 120mm)
Exclusive to 120mm
Common to 70 mm
and 120 mm
Electric bobbin winder
2-pedal unit
for standing work
B1552-781-000-A
(6.4~19.1mm)
<1> (4×25mm)
D1508-771-K00-A
(6.4~19.1mm)
<1> (4×25mm)
145-24409
(6.4~31.8mm)
<3> (6×41mm)
40008658
(5~120mm)
B1552-782-000
(6.4~25.4mm)
<2> (5×35mm)
B1552-783-000
(6.4~31.8mm)
<3> (5×41mm)
A
B
It is a device for winding bobbin separately.
Work clamp Work clamp foot
Knife
size
6.4mm
(1/4")
B2702-047
-F00 F
K
I
L
V
M
A
N
P
Q
S
9.5mm
(3/8")
B2702-047
-K00-A
11.1mm
(7/16")
B2702-047
-I00
12.7mm
(1/2")
B2702-047
-L00-A
14.3mm
(9/16")
B2702-047
-V00
15.9mm
(5/8")
B2702-047
-M00-A
17.5mm
(11/16")
B2702-047
-A00
19.1mm
(3/4")
B2702-047
-N00
22.2mm
(7/8")
B2702-047
-P00
25.4mm
(1")
B2702-047
-Q00-A
31.8mm
(1-1/4")
B2702-047
-S00-A
Cloth cutting knife
Part No.
Mark
A
B
For stitch width 5mm For stitch width 6mm
LBH-1790A (standard)
Part No.
(Length of cloth cutting knife)
<Type> (A×B)
Part No.
(Length of cloth
cutting knife)
(A×B)
Part No.
(Length of cloth
cutting knife)
<Type> (A×B)
D1511-771
-KA0-A
<1>
D1511-772
-KA0
<2>
D1511-773
-KA0
<3>
Part No.
<Type>
40008646
Part No.
Option (for knits) LBH-1795A (standard) LBH-1790S (standard)
D1508-772-K00
(6.4~25.4mm)
<2> (5×35mm)
D1508-773-K00
(6.4~31.8mm)
<3> (5×41mm)
1795
S
1790
S
: Supplied as an accessory (For LBH-1790A): Factory installed on machine
: Factory installed on machine
For needle
throwing width Part No. (Marking: A×B)
5mm
Standard (S) For Knits (option)
400-04350 (1.4×6.2mm)
6mm 400-04351 (1.4×7.4mm)
400-04352 (1.2×6.2mm)
400-04353 (1.2×7.4mm)
Model name
Needle bar stroke
Size of cloth cutting knife
Bartacking width
Buttonhole length
Precision of needle throwing mechanism
Needle thread tension
Number of stitches
Needle (at the time of delivery)
Hook
Lift of the work clamp
Auto-lifter
Needle throwing system
Cloth feeding system
Cloth cutting knife system
Number of standard patterns
Number of patterns that can be input
Bobbin thread winder
Machine head drive system
Power requirement/ Power consumption
Sewing speed
Lubrication
Lubricating oil
Weight
LBH-1790A Series
34.6mm
6.4~31.8mm (1/4"~1-1/4")
Max. 5.0mm (with special-specification part: Max. 10mm*)
Max. 41mm (optional: 70mm, 120mm) , LBH1795:120mm
0.05mm
Active tension (electronic thread tension control system)
Automatically computed from the size of the buttonhole and stitch pitch
DP×5 (#11J) #11J~#14J
DP type, full-rotary hook
Non-lubricated hook (optional)
14mm (17mm when the reverse-rotation needle-up function is used)
Provided as standard (stepping motor type)
Stepping motor
Intermittent feed by stepping motor
Stepping motor
31 patterns
Max. 99 patterns
Built-in the machine head
Compact AC servomotor (direct-drive system)
3-phase 200~240V/250VA
Max. 4,200sti/min, Normal 3,600sti/min
When the non-lubricated hook (optional) is used: 3,300sti/min
Only the hook section needs a minute-quantity lubrication.
✽No lubrication is required when the non-lubricated hook (optional) is used.
Hook: JUKI New Defrix Oil No.1 (equivalent to ISO VG7)
Machine head (include motor) 55kg, Control box 6kg
✽
✽
“sti/min”stands for “Stitches per Minute”
The special-specification part is available on a special order. Contact our branch or office in your area.
★
★
★
CompactFlash or CFA specification compatible media.
“CompactFlash ” is a registered trademark of SanDisk Corporation, U.S.A.
Other company names and product names/brand names are trademarks or registered trademarks of the respective companies.
Mark
Other option parts for knite
Description
Hook asm.
Hook timing gauge
Part No.
13782065
13782107
By the installation of non-lubricated hook, the machine is
changed to be a fully dry-head machine. (In this case, the
maximum sewing speed will be 3,300sti/min)
The work clamp is applicable to
the sewing length of 70mm or
120mm. With this work clamp,
holing of belt holes in child seat is
possible.

Juki Corporation operates an environmental management system
to promote and conduct the following as the company engages in
the research, development, design, sales, distribution,and
maintenance of industrial sewing machines, household sewing
machines, industrial robots, etc., and in the provision of sales and
maintenance services for data entry systems:
(1) The development of products and engineering processes
that are safe to the environment
(2) Green procurement and green purchasing
(3)
Energy conservation (reduction in carbon-dioxide emissions)
(4) Resource saving (reduction of papers purchased, etc.)
(5) Reduction and recycling of waste
(6) Improvement of logistics efficiency (modal shift and
improvement of packaging, packing, etc.)
SEWING MACHINERY BUSINESS UNIT
DECEMBER, 2013 Printed in Japan(C)
2-11-1, TSURUMAKI, TAMA-SHI,
TOKYO 206-8551, JAPAN
PHONE : [phone]
FAX : [phone]
http://www.juki.com
Specifications and appearance are subject to change without prior notice for improvement.
Read the instruction manual before putting the machine into service to ensure safety.
This catalogue prints with environment-friendly soyink on recycle paper.
MC602
LBH179 AS
S
Machine head
Control box
WHEN YOU PLACE ORDERS
Please note when placing orders, that the model name should be written as follows:
To order, please contact your nearest JUKI distributor.
JUKI ECO PRODUCTS The LBH-1790A Series is an eco-friendly product which complies with
JUKI ECO PRODUCTS standards for protecting the environment
The RoHS Directive is an EU Directive limiting the use of 6 hazardous substances (lead, hexavalent chromium, mercury, cadmium, PBB and PBDE) in electrical and electronic equipment.
The Juki Green Procurement Guideline is the voluntarily established criteria to eliminate not only the aforementioned six substances, but also other ones which also adversely affect the environment.
For details of JUKI ECO PRODUCTS, refer to: http://www.juki.co.jp/eco_e/index.html
This sewing machine reduces power consumption by 27% as compared with the conventional models.
The sewing machine complies with the "Juki Group Green Procurement Guidelines" on the use of
hazardous substances, which is stricter than other restrictions, such as those of the RoHS Directive.
CodeOperation panel
S
Standard
CodeType
S
Standard
Code
Model
Knife width Work clamp type
0
6.4~22.2mm 4mm × 25mm
5
6.4~31.8mm 5mm × 120mm
CodePower supply
E
K
N
3-phase 200~240V
Single-phase
220~240V
CE 220~240V
(not provided with power switch)