Question

Which one of the following sewing machine parts is situated on the arm of the machine?

• A. Spool pin
• B. Throat plate
• C. Bobbin
• D. Oscillating hook

Hint:

All components related to the upper thread path (spool pin, thread guide, tension disc, and take-up lever) are located on the arm, while components for the lower thread path (bobbin, bobbin case, and hook) are located beneath the bed.

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
A standard lockstitch sewing machine is divided into two main structural sections: the flat horizontal bed (base) and the upright, curved upper arm.
Understanding where different parts are located is essential for machine operation and troubleshooting.

Step 2: Detailed Explanation:
Let us analyze the physical locations of the listed sewing machine components:
Spool Pin (A): A vertical or horizontal metal or plastic pin situated on the top arm of the sewing machine.
Its primary function is to hold the spool of upper thread securely in place as it unwinds.
Throat Plate (B): A flat semi-circular metal plate situated on the bed of the machine directly beneath the needle and presser foot.
It features openings for the needle and the feed dogs.
Bobbin (C): A small, low-capacity spool that holds the lower thread. It is housed in the bobbin case situated under the bed of the machine.
Oscillating Hook (D): A hook mechanism situated beneath the throat plate on the bed of the machine.
It rotates or oscillates to catch the needle thread loop and pass it around the bobbin thread to form a lockstitch.
Therefore, only the spool pin is located on the upper arm of the machine.

Step 3: Final Answer:
The sewing machine part situated on the arm of the machine is the Spool pin.