NEIEP Mechanics Practice Exam

What is the frame of a DC machine commonly called?

1. Stator

2. Yoke

3. Rotor

4. Base plate

The correct answer is: Yoke

The frame of a DC machine is commonly referred to as the yoke. The yoke serves as a structural component that supports the machine and houses the other parts of the motor or generator, such as the field windings. It is typically made from ferromagnetic materials, which helps in providing a path for the magnetic flux generated by the field windings. Using the term "yoke" emphasizes its role in not just supporting the mechanical structure but also enhancing the magnetic characteristics of the DC machine. This is important because a strong magnetic field is crucial for the efficient operation of the machine. The yoke connects both ends of the field coils and completes the magnetic circuit, thus playing a vital role in the overall function of the machine. In contrast, terms like "stator" and "rotor" are more specifically associated with the two principal parts of an electromagnetic machine, with the stator generally being the stationary part and the rotor being the moving part. The base plate refers to the mounting surface of the machine, further distinguishing it from the actual yoke that encompasses the windings and magnetic components. This distinction underlines the importance of understanding the terminology in electrical machinery.