CN202150835U

CN202150835U - Special frequency converter for carving and milling machine

Info

Publication number: CN202150835U
Application number: CN201120081313U
Authority: CN
Inventors: 张建军; 祝元北
Original assignee: SHANGHAI ZHONGCHEN ELECTRONIC TECHNOLOGY Co Ltd
Current assignee: SHANGHAI ZHONGCHEN ELECTRONIC TECHNOLOGY Co Ltd
Priority date: 2011-03-24
Filing date: 2011-03-24
Publication date: 2012-02-22
Anticipated expiration: 2021-03-24

Abstract

The utility model discloses a special frequency converter for a carving and milling machine. The effect is to regulate the speed of the main shaft of the carving and milling machine; a rectification unit transforms the alternating current with a fixed work frequency to a direct current; the transformed electric energy is stored by a capacitor with a high volume; the inverter employs an electric switch comprising a large power switch transistor array to transform the direct current to square waves of different frequencies, widths and amplitudes; and a control unit works according to a set program, controls the amplitudes and the pulse widths of output square waves which are superposed to an alternating current approximate to the sine wave, the alternating current motor is driven, thereby the speed regulation of the main shaft of the carving and milling machine is realized.

Description

Carving mills the machine special converter

Technical field

The utility model relates to the variable-frequency control technique field, and specifically a kind of carving mills the machine special converter.

Background technology

Carving mills machine (CNC engraving and milling machine) it is a kind of of Digit Control Machine Tool, it is generally acknowledged that carving mills the CNC milling machine that machine is to use little cutter, high-power and high-speed main spindle motor.The advantage of engraving machine is at carving, if the rapidoprint hardness ratio seems unable to do what one wishes than conference, carving mills the appearance of machine can fill up this blank, and carving mills machine both can be carved, but also milling is a kind of efficient high-precision Digit Control Machine Tool.The important composition parts that carving mills machine are spindle motors; Present domestic spindle servo system mainly adopts DC servomechanism, and part adopts the then whole dependence on import of the spindle servo system of AC speed regulating, costs an arm and a leg; Other asynchronous machine alternating-current actuating system overwhelming majority also adopts the import frequency converter; Mainly be that requirement has bigger low-frequency torque, steady speed precision is high, and it is fast to start, shut down response.

The utility model content

The purpose of the utility model is for providing a kind of speed governing convenient, and low-frequency torque is big, and steady speed precision is high, and the carving of start, dwell time is short mills the machine special converter, improves the automaticity that carving mills machine, improves the useful life that carving mills machine, reduces the cost that carving mills machine.

Realize that the technical scheme that above-mentioned technical problem adopts is following:

Carving mills the machine special converter; Comprise ac rectifier, DC frequency-changing circuit and high speed processor, said ac rectifier is the three-phase alternating current rectifier bridge that diode is formed, the charging capacitor of two ends parallel connection two series connection of said three-phase alternating current rectifier bridge; And the output of three-phase commutation bridge connects a charging resistor; Said charging resistor parallel connection one contactor, three groups of insulated gate bipolar transistors of two charging capacitors parallel connection of series connection, every group comprises two insulated gate bipolar transistors; And the emitter of every group of two insulated gate bipolar transistors and collector electrode junction export motor to, and the base stage of three groups of insulated gate bipolar transistors is connected respectively to high speed processor.The utility model receives external signal through high speed processor direct current component is carried out the frequency adjustment, thereby reaches the order ground of control motor rotation, and the frequency adjustment mode is adjustable, mainly uses outside terminal multistage speed and analog quantity voltage regulative mode; High speed processor adopts the V/F control model, and the V/F curve can be adjusted, the torque in the time of can suitably effectively improving low frequency; Exploitation automated torque compensate function, can be when improving low frequency the output voltage of frequency converter, thereby the torque when improving low frequency; Develop automatic slip compensate function, when the load of spindle motor increases, can on the basis of setpoint frequency, increase suitable frequency converter output frequency automatically, effectively remedy the slippage of motor; P/+, Pr connect brake resistance, the kinetic energy when consuming the motor deceleration indirectly, the stability of system when improving deceleration.

The beneficial effect of the utility model is: the utility model applies to carve and mills in the middle of the machine system, makes carving mill the machine system and has following advantage: low frequency moment is big, output is steady; The torque dynamic response is fast, steady speed precision is high; Ramp to stop speed is fast; Antijamming capability is strong.

Description of drawings

Fig. 1 is the main components and parts circuit theory diagrams of the utility model

Fig. 2 is the utility model systematic schematic diagram

R, S, T are three-phase 380V power supply; M mills machine specialized high-speed spindle motor for carving; The input terminal that FWD, REV just change, reverse for control; SC is the multifunction terminal common port

Embodiment

Below in conjunction with accompanying drawing and specific embodiment the utility model is described further.

Like Fig. 1, shown in Figure 2, the utility model carving mills the machine special converter, mainly is made up of strong power part, weak current part.

The utility model carving mills the machine special converter and comprises ac rectifier, DC frequency-changing circuit and high speed processor; Said ac rectifier is the three-phase alternating current rectifier bridge that diode is formed; The charging capacitor of two ends parallel connection two series connection of said three-phase alternating current rectifier bridge; And the output of three-phase commutation bridge connects a charging resistor; Said charging resistor parallel connection one contactor, three groups of insulated gate bipolar transistors of two charging capacitors parallel connection of series connection, every group comprises two insulated gate bipolar transistors; And the emitter of every group of two insulated gate bipolar transistors and collector electrode junction export motor to, and the base stage of three groups of insulated gate bipolar transistors is connected respectively to high speed processor.

Strong power part: input three-phase AC380V is charged as DC540V through starting resistance to electrochemical capacitor through the three-phase commutation bridge rectification, when the charging end, and the contactor adhesive, charging resistor is by bypass.Through the different ON time of control IGBT, DC 540V is modulated into the sine voltage of three-phase changeable frequency, and drive motors is realized speed governing.

Weak current part: accomplish by high speed processor.

Carving mills machine and receives that the outside terminal input is just changeed, reverse signal: provided by normal open switch, be input to FWD, REV terminal respectively, the rotating operation of control spindle motor; The analog quantity voltage input signal is linked into frequency converter FIV terminal, the running frequency of control of conversion device; The frequency adjustment mode is mainly used the analog quantity voltage regulative mode, the corresponding 0～750Hz of 0～9V, and analog quantity voltage is given by host computer, and is easy to operation.

Output control: the IGBT inversion control, adopt sinusoidal pulse width modulation (SPWM) control mode.The characteristics of SPWM (Sinusoidal Pulse Width Modulation) control mode are that control circuit is simple in structure, cost is lower; Mechanical property hardness is also better; Can satisfy the stepless speed control requirement of general transmission, be used widely in the every field of industry.Can fully satisfy the various specification requirements that carving mills the machine special converter.

High speed processor mills the professional control flow software of machine technological requirement through a cover to carving, has realized:

1) frequency is adjustable continuously, high starting torque: 150% starting torque.

2) the frequency adjustment mode is various, and available analog quantity voltage input (FOV) also can use outside terminal multistage speed as the frequency setting mode as the frequency adjustment mode.

3) can set the V/F curve arbitrarily, cooperate the compensated torque function, 100%～150% starting torque is provided.

4) omnibearing detection defencive function: have in overvoltage, under voltage, motor overload, the acceleration/running stall prevent defencive function, frequency detecting.

5) start in short-term, hold function: frequency converter drives spindle motor and can in the extremely short time, realize the startup of spindle motor and stop.

The foregoing description only as the explanation to the utility model, limits the utility model never in any form.Any be equal to or the technical scheme of equivalent transformation gained all within the protection of the utility model interest field.

Claims

1. a carving mills the machine special converter; Comprise ac rectifier, DC frequency-changing circuit and high speed processor; It is characterized in that: said ac rectifier is the three-phase alternating current rectifier bridge that diode is formed; The charging capacitor of two ends parallel connection two series connection of said three-phase alternating current rectifier bridge, and the output of three-phase commutation bridge connects a charging resistor, said charging resistor parallel connection one contactor; Three groups of insulated gate bipolar transistors of two charging capacitors parallel connection of series connection; Every group comprises two insulated gate bipolar transistors, and the emitter of every group of two insulated gate bipolar transistors and collector electrode junction export motor to, and the base stage of three groups of insulated gate bipolar transistors is connected respectively to high speed processor.

2. a kind of carving according to claim 1 mills the machine special converter, it is characterized in that: said high speed processor receives external signal direct current component is carried out the frequency adjustment, and the frequency adjustment mode is used outside terminal multistage speed or analog quantity voltage regulative mode.