Skip to content
Home » NEWS » What are the structural characteristics and performance requirements of CNC machine tools?

What are the structural characteristics and performance requirements of CNC machine tools?

Although CNC machine tools also have the same components as ordinary machine tools, such as the bed and columns, guide rails, operating tables, and tool holders, in order to compare with the high-precision and high-speed control of the control system, the structural design of the main machine part of the machine tool also puts forward requirements such as high precision, high rigidity, low inertia, low friction, no gap, high resonant frequency, and appropriate damping ratio. Due to the specific performance of the mechanical structure form, the core factor for achieving performance is feasibility, and the key components of CNC machine tools have undergone major changes in structural design.
Structural characteristics of CNC machine tools:
I. Structural characteristics of basic components
(1) The main function of basic components
The basic components of CNC machine tools are an important foundation. Their basic function is to support and maintain the relative position of each actuator. CNC machine tools integrate precision machining. They must be able to withstand the maximum cutting force of large cutting and large cutting during rough machining, and must be able to ensure high precision during precision machining.
(2) Performance requirements of basic components
The structural design of the basic components has high requirements in terms of strength, rigidity, vibration resistance, thermal deformation, and internal stress.
(3) Improvement methods for basic components
The casting adopts a fully enclosed cross-section, reasonably arranges partitions and ribs, contains sand molding or fills concrete and other materials, widens the guide rail surface, and uses an inclined bed and guide rails for easy chip removal. The bed and column tools are welded with steel, which can significantly improve their rigidity. The layout is based on the principle of thermal symmetry, which can also increase the heat dissipation and heat insulation effect.

  1. Structural characteristics of the transmission module
    (1) The main function of the transmission module
    The main transmission module realizes the cutting power required by various tools and tools, and ensures constant power output within a large speed range. At the same time, in order for the CNC machine tool to obtain the best cutting speed, the main transmission must achieve stepless speed change within a wide range. The current CNC machine tools use high-performance DC and AC stepless speed regulation spindle motors, which greatly simplifies the graded speed change transmission chain of the machine tool.
    (2) Performance requirements of the transmission module
    The requirements for the accuracy, rigidity, vibration resistance and thermal deformation performance of the spindle assembly, which have a direct impact on the accuracy. This can be guaranteed through the structural design of the spindle assembly and the reasonable bearing combination and the selection of high-precision special bearings.
    (3) Improvement method of transmission module
    In order to improve efficiency and automation, the spindle applies automatic clamping, chipping and cutting of cutting tools or tools, and accurate shutdown. The new ceramic spindle is light in weight, low in thermal expansion rate, and has high precision and accuracy.
    III. Characteristics of feed module
    (1) Main function of feed module
    The module driven by motor, ball screw and tool or workpiece completes movement in all directions.
    (2) Performance requirements of feed module
    When designing mechanical devices, the design of mechanical design is based on the principle of no gap, low height and high degree.
    (3) Improvement method of feed module
    Use low friction, light drag, high efficiency ball screw and linear rolling guide; the motor is directly connected to the screw, which simplifies the feed transmission chain; the anti-backlash device eliminates the transmission gap of gears, screws and couplings; 4 pairs of rolling guides and screws are preloaded and stretched.
    IV. Structural characteristics of other models
    (1) Operation table
    CNC milling and CNC milling center adopt the internal structure with the characteristics of CNC feed drive mechanism, rotation, indexing and feed movement of any angle of the circle. For multi-process CNC machine tools, an automatic exchange operation table is configured to further shorten the auxiliary time.
    (2) Tool holder module
    The rotary tool holder. The automatic tool change module with a tool magazine and the multi-tool holder and multi-spindle layout play an important role in improving efficiency and automation level. In order to position and clamp the tool on the machine tool, there are some standard tool means and machine clamps in some places.
    (3) CNC accessories
    The function of machine tool accessories is to cooperate with the machine tool to achieve automation. The special accessories for CNC machine tools are: 1 tool setting instrument, 2 automatic chip conveyor, 3 automatic chip conveyor, material storage and loading and unloading device, 5 automatic cooling and lubrication and various new accessories such as guide rail protective cover, etc.
    (4) Lubrication module
    The oil injection method of cutting oil is to lubricate different methods for different objects. In terms of oil injection method, various processes are similar to other works. The cutting oil system has sufficient lubrication, easy control of oil supply, strong heat dissipation and impurity removal capabilities, and the cutting oil is sucked from the oil tank by the oil pump and transported to the part that needs to be cut. The oil filling methods include: dripping method, splashing method, spraying method, etc.

Leave a Reply

Your email address will not be published. Required fields are marked *