Small engraving machine
In terms of processing principle, engraving is a combination of drilling and milling, and the engraving machine has multiple data input modes that can be easily used as needed. There are two types of computer engraving machines: laser engraving and mechanical engraving, both of which have high power and low power. Because the application range of engraving machines is very wide, it is necessary to understand the most suitable application range of various engraving machines. Small power ones are only suitable for making dual color boards, building models, small signs, three-dimensional handicrafts, etc., while carving jade, metal, etc. requires a power of over 1500W. High power engraving machines can be used for small power engraving machines. Most suitable for large-scale cutting, embossing, carving.
Technical Introduction
In CNC machine tools, the electric spindle usually adopts the method of frequency conversion and speed regulation. There are three main control methods: ordinary frequency conversion drive and control, vector control driver drive and control, and direct torque control.
Ordinary frequency conversion is scalar drive and control, and its drive control characteristics are constant torque drive, with output power proportional to rotational speed. The dynamic performance of ordinary frequency conversion control is not ideal, and the control performance is poor at low speeds. The output power is not stable enough, and it does not have the C-axis function. However, due to its low price and simple structure, it is generally used for grinding machines and ordinary high-speed milling machines.
Vector control technology simulates the control of DC motors, using rotor magnetic field orientation and vector transformation to achieve drive and control, with good dynamic performance. The vector control driver has a large torque value at the beginning of startup. In addition, the electric spindle itself has a simple structure and small inertia, so the startup acceleration is large, which can achieve the allowable limit speed instantaneously after startup. This type of driver has two types: open loop and closed loop. The latter can achieve position and speed feedback, not only having better dynamic performance, but also achieving C-axis function; The former has slightly poor dynamic performance and does not have C-axis functionality, but is relatively inexpensive.
Direct torque control (DTC) is a new high-performance AC speed regulation technology developed after vector control technology. Its control idea is novel, and its system structure is concise and clear. It is more suitable for driving high-speed motorized spindles, and it can meet the requirements of high-speed motorized spindles for high rotational speed, wide speed range, and high-speed instantaneous accurate stop dynamic and static characteristics. It has become a hot technology in the field of AC transmission.