My Mom's old Singer Zig Zag 457 stopped working and I am trying to fix it. She needs to finish lining her curtains. Better late than never. I hope someone here can help.

The bobbin stopped spinning. I flipped the machine over and took off the bottom plate. You see this (I removed the belt):

{{!gwi}}

The wheel under the bobbin turns freely. The wheel on the right, that is turned by the motor, feels like it is spun.

I can feel the "driveshaft" turning inside of the wheel.

How do I take it off? There are no screws.

What is it called, so I can order a new one?

Sorry that I don't know the termanology. I hope this makes sense.

Thanks,