A lathe is a machine tool primarily used for shaping a rotating workpiece by turning it with a cutting tool.
In addition to turning, a lathe can also be used for machining operations such as drilling, reaming, tapping, thread cutting, and knurling with specialized tools.
The primary components of a lathe include: the headstock, gearbox for tool changes, feed box, slide box, tool holder, tailstock, lead screw, bed, foot, light rod, and cooling system.
The headstock, also known as the spindle box, plays a crucial role in transmitting rotary motion from the main motor to the spindle through a series of gear changes, allowing the spindle to achieve the desired forward and reverse speeds. The headstock also diverts some of its power to drive the feed box.
The spindle in the headstock is a critical component of the lathe. The smoothness of the spindle’s operation on its bearings directly impacts the quality of the machined workpiece. If the accuracy of the spindle’s rotation decreases, the value of the machine tool is diminished.
The feed box, also referred to as the knife box, is equipped with a gear mechanism for the feed movement. The gear mechanism is adjusted to achieve the desired feed rate or pitch, and the motion is transmitted to the tool holder through the light rod or lead screw for cutting purposes.
Lead screw and light rod
The lead screw is utilized to link the feed box to the slide box, facilitating the transfer of movement and power from the feed box to the slide box, enabling the slide box to achieve longitudinal linear motion.
The lead screw is specifically engineered to rotate various threads.
During other surface turning operations on the workpiece, only the light rod is employed and the lead screw is not utilized.
It is important to differentiate between the light rod and the lead screw based on the components of the slide box.
The control box is responsible for managing the feed motion of the lathe.
It contains a mechanism that converts the rotary motion of the light rod and the lead screw into linear motion for the tool holder.
The light rod drive is responsible for the longitudinal feed movement, lateral feed movement, and rapid movement of the tool holder.
The lead screw drives the tool holder for longitudinal linear motion, allowing for thread turning.
The slide box is composed of two levels of slides (medium and small slides), a saddle, and a tool holder.
It serves as the mounting point for the turning tool and drives its longitudinal, lateral, or oblique movement.
The tailstock is mounted on the bed rail and can be moved along its length to adjust its working position.
Its primary function is to support longer workpieces by providing a rear tip, as well as to hold drills, reamers, etc. for hole machining operations.
The bed is a significant component of a lathe and features a highly precise guide rail (consisting of a bed rail and flat rail).
It serves to support and connect the various parts of the lathe and ensures that they maintain accurate relative positions during operation.
The cooling device primarily pressurizes the cutting fluid in the water tank using the cooling water pump and then sprays it onto the cutting area. This helps to reduce the cutting temperature, wash away chips, and lubricate the machining surface, thereby improving the tool life and enhancing the surface quality of the workpiece.