Explain the principal parts of the drilling machine and illustrate the working mechanisms of the drilling machine?

The principal parts of a drilling machine include:

1. Base: The base is the foundation of the drilling machine and provides stability during operation.

2. Column: The column is a vertical support structure that holds the drill head and allows it to be raised or lowered.

3. Drill head: The drill head contains the motor, spindle, and chuck, which hold and rotate the drill bit.

4. Table: The table is a flat surface that supports the workpiece and can be adjusted in height and angle to accommodate different drilling needs.

5. Spindle: The spindle is a rotating shaft that holds the drill bit and is driven by the motor to create the drilling action.

6. Chuck: The chuck is a device that holds the drill bit in place and allows for easy changing of drill bits.

The working mechanism of a drilling machine involves the following steps:

1. The workpiece is securely clamped to the table or held in a vise.

2. The drill bit is inserted into the chuck and tightened securely.

3. The spindle is lowered to the desired depth by adjusting the column or using the feed handle.

4. The motor is turned on, causing the spindle to rotate and the drill bit to cut into the workpiece.

5. The operator applies downward pressure on the feed handle to control the drilling speed and feed rate.

6. Once the desired depth is reached, the spindle is raised, and the drill bit is removed from the workpiece.

Overall, the drilling machine is a versatile tool that is used in various industries for creating holes in different materials with precision and efficiency.