Global BM 345 User manual

PRODUCED BY
INDUSTRIAL SEWING MASCHINES
BM 345
Mechanic´s Instrutions

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Mechanic´s instructions
BM345
Table of contents
1General notes on safety ...............................................................................................5
2General notes ...............................................................................................................7
2.1 Operating instructions ........................................................................................7
2.2 Class designations, machine number and initial basis for descriptions ..............7
2.3 Applications of the machine ...............................................................................7
2.4 Technical data of machine .................................................................................8
2.5 Notes on repair and adjustments......................................................................10
2.6 Needle plate assembly .....................................................................................10
2.6.1 Removing the needle plate..............................................................10
2.6.2 Installing the needle plate................................................................11
2.6.3 Adjusting the needle plate (figure 1)................................................11
2.6.4 Replacing the needle slide plate (figure 3) ......................................11
2.6.5 Adjusting the cloth retainer (figure 2)...............................................12
2.7 Needle lever .....................................................................................................13
2.7.1 Assembly.........................................................................................13
2.7.2 Adjusting the needle stroke (figure 5, figure 6 and figure 8) ............14
2.8 Loop stroke ......................................................................................................16
2.8.1 Adjusting the loop stroke .................................................................16
2.9 Gripper .............................................................................................................17
2.9.1 Removal and installation of the gripper shaft ..................................17
2.9.2 Gripper deflection (figure 7).............................................................17
2.9.3 Adjusting the gripper (figure 8) ........................................................18
2.10 Transporters .....................................................................................................19
2.10.1 Adjusting the transporter (figure 9)..................................................19
2.11 Transport brackets ...........................................................................................20
2.11.1 Adjusting the transport brackets......................................................20
2.11.2 Adjusting the airing for the transport bracket (figure 9)....................20
2.12 Presser.............................................................................................................21
2.12.1 Replacing the presser shaft (figure 10) ...........................................21
2.12.2 Adjusting the presser (figure 11) .....................................................22
2.12.3 Adjusting the material support arm..................................................23
2.13 Interval gear (figure 12) ....................................................................................23
2.13.1 Setting the interval gear (figure 12) .................................................23
We reserve the right to make design changes.

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1 General notes on safety
Failure to comply with the following safety instructions can lead to bodily
injury or damage to the machine.
1. The machine must only be operated by persons familiar with the relevant
operating instructions and who have been instructed accordingly.
2. Before commissioning also read the notes on safety and the operating
instructions of the sewing drive manufacturer.
3. Only use the machine in the intended manner and never without the
provided guards. Always observe the pertinent safety regulations.
4. Switch off the main switch or pull the power plug for threading, changing
the reels, exchanging sewing tools such as needle, gripper, needle plate,
transport devices, possibly cutter and cutting block, for cleaning and when
leaving the workplace as well as for maintenance. When using
mechanically actuated clutch motors not equipped with actuation locks,
always wait until the motor comes to a standstill.
5. General maintenance tasks may be carried out only by properly trained
persons in accordance with the operating instructions.
6. Repair work, retrofitting and maintenance may be carried out only by
technicians or specially trained personnel.
7. When servicing or repairing pneumatic equipment, the machine must be
disconnected from the pneumatic supply. Exceptions are only allowed for
adjustment work and tests of functionality performed by specially trained
technicians.
8. Only specially qualified technicians may work on the electrical equipment.
9. It is forbidden to work on electrically live components! Exemptions are
covered by the EN50110 (DIN VDE0105) regulations.
10. Any retrofitting or alterations to the machine may only be performed under
strict compliance with all pertinent safety regulations.
11. Only use our approved spare parts when servicing and/or repairing the
machine.
12. It is forbidden to operate the upper component until it is determined that the
entire sewing unit complies with EU provisions.

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13. Warning instructions given in the operating instructions that pertain to
especially dangerous parts of the machine must be indicated at these
positions using a safety symbol.
Warning instructions given in the operating instructions that pertain to
special injury hazards for operating personnel or technicians must be
indicated at these positions using a safety symbol.
It is essential that you observe and follow these instructions as well as the
generally valid safety regulations.

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2 General notes
2.1 Operating instructions
Every person in charge of setting up, operating, servicing and repairing the
machine must first read and understand the operating instructions and
particularly the safety instructions before starting up the machine.
2.2 Class designations, machine number and initial basis for
descriptions
The operating side of the machine is the initial basis for left/right descriptions.
The class designation (type) and machine/model numbers are fastened to the
rear of the machine case.
This data is also noted on the front cover page of the operating instructions.
2.3 Applications of the machine
The BM345 is especially suitable for blind-stitch seams on thin to medium thick
materials and knitted goods.

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2.4 Technical data of machine
Stitch number: Mechanical maximum: 3000 min-1
Recommended nominal stitch number: 2200 min-1
Belt pulley diameter/machine dw 80 mm
V-belt profile 10 × 6 mm
Tooth-belt pulley/machine Z = 38
Tooth-belt profile HTD 5M-9
Stitch length 5–8 mm adjustable
Stitch type Single thread-chain stitch-blind stitch
Interval: 1:2 connectible
Needle system STROBEL 1669 EEO
Needle thickness 60, 70, 80, 90
Needle system optional STROBEL 4669 EEO
Needle thickness 65, 80, 90
Thread (recommended) Polyester, continuously twined
Thread thickness (recommended) 120/2, 200
Stitch type 103
Operating noise:
Avg. SPL at measurement surface for stitch number
n = 2200 min-1: LpAm 71 dB(A)
Noise levels in acc. with DIN 45635-48-1 KL3

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2.5 Abridged version of adjustment manual for BM345
Theoretical needle radius: 41.3 mm
Left needle guide: 41.33 +0.02 mm
Needle slide plate: 41.30 ±0.01 mm
Right needle guide: 41.36 +0.05 mm
Needle stroke, eye of needle to gripping finger: 1.5 +0.5 mm
Ball pin to needle shaft: 2 ±0.5 mm
Slit in ball pin: approx. 15°
Gripper deflection: 18 +0.5 mm
Contact pressures:
Transport bracket: Left 12 N
Right 12 N
Material support arm: 140 N (measured at presser shaft)
Presser contact: 6 N
Transport length: approx.5–8 mm
Airing value between needle plate and transport brackets: approx. 13 mm
Airing value between needle plate and presser: approx. 10 mm
Loop stroke: 2.3–3.0 mm

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2.5 Notes on repair and adjustments
CAUTION! Injury hazard!
Read the safety and operating instructions before
performing maintenance and/or repair work. Failure to
comply with them can lead to severe bodily injury.
2.6 Needle plate assembly
CAUTION! Injury hazard!
Switch off the machine electrically!
Needle plates are adjusted at the factory and can be easily exchanged in their
entirety. When replacing needle guide(s), the adjusting dimensions must be
rechecked using a dial gauge. After removing the needle lever, the dial gauge is
inserted into the needle shaft and, by turning the handwheel, touches the surface
of the needle guide.
2.6.1 Removing the needle plate
1. Switch off the machine electrically
2. Remove the needle and needle lever
3. Loosen the fastening screws of the needle plate and remove the entire
needle plate with the clamp facing forwards.

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2.6.2 Installing the needle plate
Install the needle plate in the reverse order.
The needle plate opening must lie centrally relative to the presser and the
needle plate must lie horizontally.
Install in the reverse order. Ensure that the needle plate opening lies centrally
relative to the presser and that the needle plate lies horizontally.
2.6.3 Adjusting the needle plate (figure 1)
At the left needle guide, the theoretical needle radius of 41.3 mm should be
0.03 to 0.05 mm larger. At the needle slide plate, it should be 0.01 mm smaller
to 0.01 mm larger and at the right needle guide it should be 0.06 to 0.08 mm
larger.
The adjustment must be made using a dial gauge. Deviations lead to
significantly poorer sewing results and may even cause preliminary damage or
wear to the the sewing tools.
Figure 1
2.6.4 Replacing the needle slide plate (figure 3)
The needle slide plate on the central base of the needle plate can be removed
after loosening the screw (5).
When assembling, ensure that the needle slide plate lies firmly against the base.
Needle plate_adjusting_01

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2.6.5 Adjusting the cloth retainer (figure 2)
After replacing the needle plate, check whether the cloth retainer (7) figure 3
lies centrally on the presser. This is particularly important for roof-shaped
pressers/cloth retainers to ensure that the material is optimally held during
sewing.
Figure 2
Figure 3
Cloth retainer_adjusting_02

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2.7 Needle lever
2.7.1 Assembly
CAUTION!
Switch off the machine electrically!
Remove screw (10) figure 5, move the thread feeder and remove the needle
lever. During installation, please ensure that the needle runs through the
centre of the needle groove and the needle tip is flush with the left needle
guide (figure 4).
Figure 4
Needle lever_assembly_01

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2.7.2 Adjusting the needle stroke (figure 5, figure 6 and figure 8)
For a loop stroke of 2.3–3.0 mm, the needle stroke must be set to that the left
side of the needle’s eye is approx. 1.0 +0.5 mm away from the large gripping
finger when the tip of the large gripping finger is above the centre of the needle
(figure 8).
The head cover must be removed for the adjustment. After removing (hex key
size 4) screw (1) shown in figure 6, the ball pin (2) shown in figure 5 can be
adjusted using a slotted screwdriver.
In the horizontal position, insert the ball pin so that the slot of the ø6 bolt stands
vertically beneath the ø7 bolt.
Rotating it clockwise will result in a larger needle stroke while turning it in the
opposite direction will create a smaller needle stroke.
The distance between the ball pin and needle shaft is 2 ±0.5 mm. After
adjusting the needle stroke, the needle lever must be configured as described in
section “2.7.1 Assembly”.
Tighten the screw (1) shown in figure 6.
Check the gripper and needle movement by turning the main shaft using the
handwheel.

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Figure 5
Figure 6

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2.8 Loop stroke
The loop stroke is the path of the needle from its right reversal point to the point
where the tip of the large gripping finger stands above the centre of the needle.
(Figure 8)
2.8.1 Adjusting the loop stroke
Caution!
Switch off the machine electrically!
In the factory setting, the loop stroke is 2.3–3.0 mm. (Figure 8)
Adjustment:
- Unscrew the head of the connecting rod: Loop stroke becomes smaller
- Screw in the head of the connecting rod: Loop stroke becomes larger
Thread slope = 0.5 mm per rotation
The following steps are required to rotate the head of the connecting rod
(figures 5 and 6):
1. Unscrew the fillister head screw (9) figure 5 and push the gripper forwards.
2. Remove the nut (5) figure 5 from the gripper shaft.
3. Remove the cylinder head screws (4) figure 5 from the head of the
connecting rod (3) figure 5.
4. Remove the adjusting ring (3) figure 6 and pull out the gripper shaft
including the head of the connecting rod (3) figure 5 from the cross-beds
(5) figure 6.
Do not remove the contoured bolt (4) figure 6!
The loop stroke can be determined using a special dial gauge or
vernier caliper.

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2.9 Gripper
Removing and installing the gripper (figure 5)
CAUTION!
Switch off the machine electrically!
After removing the fillister head screw (9), the gripper can be removed from the
front.
When installing, ensure that the fastening surface of the gripper lies within the
chuck and is fully inserted. Tighten the fillister screw (9).
2.9.1 Removal and installation of the gripper shaft
After removing the gripper and loosening the adjusting rings (8) figure 5 and
(3) figure 6, the gripper shaft can be removed together with the ball joint lever
(7) figure 5.
2.9.2 Gripper deflection (figure 7)
The gripper deflection is 18 +0.5 (specification).
Figure 7

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2.9.3 Adjusting the gripper (figure 8)
At the moment when the loop is picked up, the gripping finger must lie
0.1–0.2 mm above the needle. This must also be observed when changing
the needle thickness. It is essential to prevent needle contact from occurring!
The horizontal distance from the large gripping finger to the eye of the needle
should be 1.5 +0.5 mm (figure 8). On the left side where the loop is released,
the needle must pass centrally in between the two gripping fingers. These
values can be adjusted by turning and moving the adjusting cam (6) figure 6
and rotating the gripper shaft against the head of the connecting rod (3) figure 5.
Check the gripper movement by carefully turning the main shaft using the
handwheel!
Check that all fastening screws are firmly installed!
Figure 8

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2.10 Transporters
The machine is equipped ex works with the pyramid-toothed transporter. After
loosening the two screws, its motion towards the needle plate can be adjusted.
2.10.1 Adjusting the transporter (figure 9)
CAUTION! Injury hazard!
Switch off the machine electrically!
1. Set the stitch length to 8 mm.
2. Clamp down the transporter so that it lies parallel to the needle plate and
the lower part of the tooth protrudes beneath the bottom of the needle plate.
It must not collide with the sides of the needle plate opening amd should be
set forwards as far as possible towards the needle.
Clamp a piece of paper with 0.2 mm to the tip of the needle 2 mm in front of the
centre of the presser.
Figure 9

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2.11 Transport brackets
2.11.1 Adjusting the transport brackets
CAUTION! Injury hazard!
Switch off the machine electrically!
The position of the transport brackets is given by the position of the angle lever
symmetrical to the presser. It should tip lightly and lie evenly against the needle
plate. The transport bracket pressure can be adjusted using separate screws for
each stand on the upper side of the material support arm.
2.11.2 Adjusting the airing for the transport bracket (figure 9)
The transport stands are pressed backwards when airing the material support
arm. The adjustable eccentric bolts serve as stops (5).
In the upper position of the material support arm, there must be approx. 2 mm
between the lever and bolts to ensure that the transport bracket presses
securely against the needle plate for every position of stitch depth control.