Modern CNC lathes have the functions of X-axis and Z-axis linkage, tool position and tool tip arc radius compensation, and machining fixed cycle.
Structure of CNC lathe
1. Brief introduction of CNC lathe
CNC lathe consists of CNC system, lathe bed, spindle, feed system, rotary tool rest, operation panel and auxiliary system.
CNC lathes are divided into vertical CNC lathes and horizontal CNC lathes.
Vertical CNC lathe is used to turn disc parts with large rotary diameter.
Horizontal CNC lathe is used to turn long or small disc parts in the axial direction.
Horizontal CNC lathes can be further divided into economical CNC lathes, ordinary CNC lathes and turning centers according to their functions.
(1) Economical CNC lathe: a simple CNC lathe formed by transforming the turning feed system of ordinary lathe with stepping motor and single chip microcomputer. Low cost, poor automation and function, and low turning accuracy. Suitable for turning rotary parts with low requirements.
Economical CNC lathe
(2) Ordinary CNC lathe: CNC lathe with special design in structure and general CNC system according to turning requirements. The numerical control system has strong functions, high degree of automation and high machining accuracy, and is suitable for turning general rotary parts. This CNC lathe can control two coordinate axes at the same time, namely X axis and Z axis.
Ordinary CNC lathe
(3) Turning center: On the basis of ordinary CNC lathe, a C-axis and a power head are added. More advanced machine tools also have a tool magazine, which can control three coordinate axes of X, Z and C. The linkage control axis can be (X, Z), (X, C) or (Z, C). With the addition of C axis and milling power head, the machining function of this CNC lathe is greatly enhanced. In addition to general turning, it can also be used for radial and axial milling, curved surface milling, and drilling holes and radial holes whose center line is not in the rotation center of parts.
2. Hydraulic chuck and hydraulic tailstock
Hydraulic chuck is an important accessory for clamping workpiece in NC turning, and ordinary hydraulic chuck can be used for general rotary parts. For parts that are not cylindrical, special chucks are needed. When machining parts directly with bar, a spring chuck is needed.
For parts with a large ratio of axial dimension to radial dimension, it is necessary to support the end of the part with a movable center installed on the hydraulic tailstock to ensure the correct machining of the part. Tailstock has common hydraulic tailstock and programmable hydraulic tailstock.
3. CNC lathe tool rest
CNC lathe can be equipped with two kinds of tool rest:
(1) The special tool rest is developed by lathe manufacturers, and the tool rest used is also special. The advantage of this tool holder is low manufacturing cost, but it lacks universality.
(2) General toolholders The toolholders produced according to certain general standards (such as VDI, German Association of Engineers) can be selected and configured by CNC lathe manufacturers according to the functional requirements of CNC lathes.
Universal tool rest
4. Milling power head
After the milling power head is installed on the tool rest of CNC lathe, the machining ability of CNC lathe can be greatly expanded. For example, the milling power head is used for axial drilling and milling axial grooves.
5. CNC lathe tools
When turning parts on a CNC lathe or turning center, we should arrange the position of the tool on the tool rest reasonably and scientifically according to the tool rest structure of the lathe and the number of tools that can be installed, and pay attention to avoid the interference between the tool and the machine tool, the tool and the workpiece and the tool when the tool is at rest or working.
Commonly used tools on CNC lathes.