Brother Bobbin Case Inner Rotary Hook | XD1855351 .
This bobbin case holds the threaded bobbin safely in the lower part of the sewing machine.
It also provides tension to the lower thread. As the needle thread is pulled around bobbin case, it wraps around the bobbin thread and pulls it up through the needle plate.
The main reason of damage to any 'drop-in' bobbin case is incorrect threading. Please ensure that you always thread the take-up lever on your sewing / embroidery machine properly.
Otherwise the thread will catch around the bobbin case and lift it from its position. This will then cause the needle to strike the bobbin case, which can potentially destroy the bobbin case and reset the needle bar timing.
Please regularly check the bobbin case condition to avoid jamming, jumping or a bad thread tension.
The bobbin case will need to be changed if necessary.
Series - Brother Innov Is 700e, 700EII and 750E Embroidery Machines.