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5-2. Needle thread clamp device
By actuating the needle thread clamp device, trouble of sewing at the high-speed start (needle thread
slip-off, stitch skipping or needle thread stain) is prevented, and can reduce gathering (bird's nest) of
needle thread on the wrong side of cloth while keeping stable sewing. When mounting the IP-420,
changeover of motion ON/OFF is performed with
key.
When the needle thread clamp device is OFF, the machine automatically operates at slow-start.
When memory switch No. 35 is
: prohibited, the thread clamp does not work. In addi-
tion,
key is ineffective.
* Matters that demand special attention when using the needle thread clamp device
Refer to the list below for the contents of memory switches where the thread clamp unit can be set.
Sewing
machine type
Thread clamp
unit type
Memory switch
U69
U70
AMS-224ENHS
H type
1 : H type thin thread (standard) (#50 to #8)
2 : H type intermediate (#20 to #5)
3 : H type thick thread (#5 to #2)
0 : Front
1 : Rear (standard)
[Regarding thread clamp unit]
Change the set value of memory switch U69 according to the thickness of needle thread. The value has
been set to 1 : Thin thread at the time of delivery.
Commendable value is Set value : 1 for thread count #50 to #8, Set value : 2 for thread count #20 to
#5, and Set value : 3 for thread count #5 to #2. (The value will change in accordance with the kind and
thickness of the actual thread and the kinds of materials to be sewn. Set the value by adjusting to the
state of needle thread on the wrong side of materials.) In addition, it is possible to select the thread
clamp position by means of memory switch U70. If the sewing material is tucked in or set in at the be-
ginning of sewing in case of using thicker thread such as yarn count #5 to #2 or in any other occasion,
select rear position of thread clamp
by means of Memory switch U70.
Use the set value of the memory switch which is adjusted to the thread clamp unit type.
When the setting is wrong, the thread clamp fails to properly function. So, be careful.