CN201752921U - Servo motor control system of full-electric injection machine - Google Patents

Abstract

The utility model discloses a servo motor control system of a full-electric injection machine, which includes an injection machine computer controller, servo motor controllers and a PLC controller; the computer controller is connected with the servo motor controllers through a CAN (controller area network) bus; the servo motor controller is connected with a servo motor; the computer controller is connected with the PLC (programmable logic controller) controller; the servo motor controller refer to a die opening and closing servo motor controller, an injection servo motor controller, a smelting and pressure maintaining servo motor controller and an ejection servo motor controller; the servo motor refer to a die opening and closing servo motor, an injection servo motor, a smelting and pressure maintaining servo motor and an ejection servo motor. The servo motor control system of the full-electric injection machine can implement synchronization control on simultaneously implemented techniques by implementing die opening and closing control, injection control, smelting control, pressure maintaining control, ejection control, ejection platform movable control and die modulating control on the motor of the electric injection machine, and save the production time by one third.

Description

The full electric injection molding machine servo control system

Technical field

The utility model relates to the electric injection molding machine field, particularly a kind of control system of servomotor of full electric injection molding machine.

Background technology

The plastic cement injection (mo(u)lding) machine is a main former of thermoplastic plastic or thermosetting plastics being made various plastic parts.Its course of work of a universal plastic cement injection (mo(u)lding) machine (following abbreviation injection machine) is as follows: granular or powdery plastic cement is sent to the warmed-up barrel with uniform temperature from the hopper of injection machine, after the process heat fused is flow regime, pass through the nozzle of barrel front end by the screw rod promotion, and in the lower closed mold of implantation temperature, plastic melt promptly becomes plasthetics through behind the cooling curing under the situation of pressurized.

Though existing hydraulic injection molding machine drive unit can produce bigger active force driving device arrangement works, realizes transmission stably, also exist a lot of not enoughly, for example, the energy consumption height, noise is big, seriously polluted, production efficiency is low etc.The existence of these factors makes full electric injection molding machine ready to appear.Deficient day by day at the energy, that ecological environment goes from bad to worse today, the research and development of environment protection-type " green " full electric injection molding machine control system and control method are more and more urgent and important, seem particularly important and wherein the control of servomotor is used.

The utility model content

The purpose of this utility model is to provide a kind of control system and control method of full electric injection molding machine servomotor, by the control of the utility model, make that it has energy savings, cleaning, noise is low, precision is high, repeatability is high, speed control range is wide, response is good, the production efficiency advantages of higher to the full electric injection molding machine servomotor.

The purpose of this utility model is achieved through the following technical solutions: a kind of servo control system of full electric injection molding machine, it is characterized in that, and comprise injection machine computer controller, servomotor controller and PLC controller; Described computer controller is connected with servomotor controller by the CAN bus, and described servomotor controller is connected with servomotor, and described computer controller is connected with the PLC controller; Described servomotor controller is meant folding mould servomotor controller, injection servomotor controller, melten gel pressurize servomotor controller and ejects servomotor controller; Described servomotor is meant folding mould servomotor, injection servomotor, melten gel pressurize servomotor and ejects servomotor.

In order to realize the utility model better, described servo control system also comprises LCD display module, Keysheet module, the ethernet control chip that is connected with described injection machine computer controller respectively; Described injection machine computer controller adopts the AMD microprocessor, and described servomotor controller adopts dsp controller (adopting the TMS320F28335 chip).

In described injection servomotor controller and the melten gel pressurize servomotor controller, the SCI module of described dsp controller connects pressure sensor, the JTAG module of dsp controller connects control emulator LED lamp, the I/O module of dsp controller connects control warning output location and finishes signal LED lamp, 2 EVA/B modules of dsp controller connect outside PWM unit, outside PWM unit by the IPM power driving device respectively with the injection servomotor, melten gel pressurize servomotor connects, injection servomotor and melten gel pressurize motor are given the ADC module feedback current signal of dsp controller respectively by current sensor, injection servomotor and melten gel pressurize servomotor are given the QEP module feedback signal of dsp controller respectively by code-disc.

Described folding mould servomotor controller and ejecting in the servomotor controller, an output of dsp controller is connected respectively to injection machine computer controller and emulator by CAN bus communication module, the jtag interface that it carries, another output connects IPM power driving device and servomotor successively by the task manager EVA/B that it carries, described servomotor is connected to the analog-to-digital conversion module ADC of chip by current sensor, and described servomotor also connects the orthogonal encoder unit QEP of chip by code-disc; Described servomotor is meant opening-closing die motor and push-out motor.

The control method of the servo control system of above-mentioned full electric injection molding machine, it is characterized in that, carry out the control of folding mould, melten gel control, injection control, holding pressure control, eject control, penetrate platform and move control and mode transfer control by servomotor electric injection molding machine, drive motors is finished the injection moulding function, the process that can carry out is simultaneously carried out Synchronization Control, to realize saving the purpose of production time.

Described control method comprises the steps:

The first step, the mode of operation of the servomotor of selection full electric injection molding machine: manual, semi or fully automatic;

Second step started the control method of servo control system according to selected pattern, and wherein manual mode is meant according to injection moulding actuation cycle technological requirement, and manually input parameter is controlled independently that folding mould, She Tai advance, melten gel, injected, ejects action; The semi-automatic work pattern is meant according to injection moulding action technological requirement, finishes the single cycle action by servo control system according to control method; The fully automatic working pattern is meant according to injection moulding action technological requirement, finishes repeatedly do action by servo control system according to the flow process of single cycle action.

Finishing single cycle action according to control method and comprise the steps: in described second step

The I step, the closed safe door;

The II step, the injection servomotor is controlled, split the matched moulds servomotor simultaneously and carry out matched moulds control;

In the III step, melten gel pressurize servomotor is carried out holding pressure control;

The IV step, melten gel pressurize servomotor is carried out melten gel control, split the matched moulds servomotor simultaneously and carry out die sinking control and eject control ejecting servomotor;

The V step, open safety door, finish.

Described the injection servomotor is controlled and melten gel pressurize motor is controlled be meant:

The injection process is: the melten gel motor is not worked, the injection motor starts, driving the injection nut rotates, and injection motor and injection nut location do not move, the injection nut drives the ball screw forward impelling, ball screw lead-screw, melten gel nut, melten gel motor advance simultaneously, finish until the injection process, and the injection motor is shut down;

The melten gel process is:

I step: the melten gel motor starts, and melten gel driven by motor melten gel nut rotates, and the melten gel nut drives screw rod and rotates, and bearing is equipped with in screw rod and ball screw junction, makes screw rod freely rotate and can not drive the ball screw rotation;

The ii step: screw rod pushes limit heating and melting material by rotation forward with the material limit, material is constantly carried toward screw head, the fused materials that accumulates in the material stock district of machine barrel produces certain pressure, pressure is increasing, lead-screw, but because the ball screw fastening screw, screw rod can not directly retreat, but make the pressure between screw rod and the ball screw increasing, at this moment, the pressure sensor that is positioned at screw rod and ball screw junction is sent to dsp controller to pressure measuring value;

The iii step: dsp controller and pressure set points compare;

The iv step: when the measured value of pressure sensor surpasses setting value, dsp controller control injection motor and injection nut begin counter-rotating, and injection motor and injection nut location do not move, ball screw shrinks back according to the speed of setting, screw rod also shrinks back, melten gel nut and melten gel motor drive screw on one side also shrink back on one side, but ball screw keeps certain pressure to screw rod;

V step: until satisfying the displacement of setting that retreats, finish resetting of injection volume and ball screw, injection motor, melten gel motor are shut down, for injection is next time prepared;

In the described melten gel process: the movement function equation that screw rod retreats is:

M: the gross weight of screw rod, melten gel nut, melten gel motor; G: acceleration of gravity; V: screw rod astern speed; F _a: the pressure that fused materials produces; F _B: the resistance of ball screw; F _L: the reaction force of fused materials; F: frictional force.

The current relationship of described melten gel motor and injection motor is:

The electric current loop open-loop transfer function is:

K _vBe the contravarianter voltage multiplication factor of outside PWM unit, K _mBe current feedback coefficient, T _vBe inverter time constant, T _v=1/f _v, f _vBe the inverter operating frequency, s is a differential, and two armature loops are made up of resistance R and inductance L, are first order inertial loop, T _OiBe the current sample time constant filter, wherein, T _OiAnd T _vConstant between being hour, equivalence is a time constant T _Ov=T _Oi+ T _v, T again _L=L/R is an armature loop time constant, and (1) formula equivalence is:

The pi regulator of motor is current correction the I type system with better dynamic property, and the adjuster transfer function is

K _p, τ _cBe respectively the proportionality coefficient and the integration time constant of pi regulator,

With the limit of the large time constant of cancellation at the zero point controlled device of electric current loop pi regulator, get τ _c=L/R=T _L, therefore the electric current loop open-loop transfer function after pi regulator is proofreaied and correct is

(2) formula is reduced to a typical I type system:

K=K wherein _pK _v/ (R τ _c);

Then the electric current loop closed loop transfer function, is:

$C\left(s\right)=\frac{G\left(s\right)}{1+G\left(s\right)}$

$=\frac{K_v{K}_p{K}_m}{{\mathrm{\τ}}_{c}s(T_{\mathrm{ov}}s+1)+K_v{K}_p{K}_m}$

$=\frac{K}{s(T_{\mathrm{ov}}s+1)+K}$

$=\frac{{{\mathrm{\&omega;}}_n}^2}{{\mathrm{<figure-callout\; id="2"\; label="s"\; filenames="HSA00000220249300011.png,HSA00000220249300031.png"\; state="\{\{state\}\}">s</figure-callout>}}^2+2\mathrm{\&xi;}{\mathrm{\&omega;}}_{n}s+{{\mathrm{\&omega;}}_{\mathrm{<figure-callout\; id="2"\; label="n"\; filenames="HSA00000220249300011.png,HSA00000220249300031.png"\; state="\{\{state\}\}">n</figure-callout>}}}^2}$

ω n is a cut-off frequency, according to the second-order system optimal performance index, gets damping ratio ξ=0.707, promptly Try to achieve K, again τ _c=L/R=T _L, determine K _p, τ _c

Described electric current loop is the interior ring of speed ring, under the situation of the transfer function that obtains electric current loop, and the speed ring closed loop transfer function:

β is a voltage vector, K _FnBe speed feedback coefficient, T _mBe motor electromechanical time constant, K _ΦBe the motor coefficient of potential,

T _OnBe the speed feedback time constant filter,

T _lAnd T _OnConstant between being hour, equivalence is a time constant T _Fs=T _l+ T _OnInertial element, then speed ring control object is:

$C_i\left(s\right)=\frac{K_{l}R{K}_{\mathrm{fn}}}{T_m{K}_{\mathrm{\&Phi;}}s(T_{\mathrm{fs}}s+1)}=\frac{K_{l}R{K}_{\mathrm{fn}}/T_m{K}_{\mathrm{\&Phi;}}}{s(T_{\mathrm{fs}}s+1)}=\frac{K_{\mathrm{on}}}{s(T_{\mathrm{fs}}s+1)}$

Speed ring proofreaied and correct be typical II type system, the speed ring adjuster is a pi regulator, and transfer function is

Speed ring open-loop transfer function after pi regulator is regulated is:

$C_s\left(s\right)=\frac{K_{\mathrm{ps}}({\mathrm{\&tau;}}_{s}s+1)K_c}{{\mathrm{\&tau;}}_{s}J{s}^2(2T_{\mathrm{fs}}s+1)},$

Kc is a proportionality coefficient, is definite value, and J is the rotor inertia of motor, is definite value, and after proofreading and correct through pi regulator, speed ring is a typical II type system, and the speed ring open-loop transfer function is:

Wherein, K _N=K _OnK _Ps/ τ _sBe speed ring open loop multiplication factor, definition open loop amplitude versus frequency characte Mid Frequency width is h=τ _s/ T _Fs, it is determining the dynamic performance index of typical II type system, h increases overshoot and reduces, but the adjusting time be not dull with the variation of h, the time of regulating when h=5 is the shortest, dynamic response is the fastest, selects suitable cut-off frequency ω again _n, calculate τ _sAnd K _Ps:

$\left\{\begin{array}{c}{\mathrm{\&tau;}}_s=h*T_{\mathrm{fs}}\\ K_{\mathrm{ps}}=\frac{h+1}{2h}*\frac{T_m{K}_{\mathrm{\&Phi;}}}{T_{\mathrm{fs}}{K}_{l}R{K}_{\mathrm{fn}}}\end{array}\right.$

The time cycle of described speed ring and gain are τ _WAnd K _W, the Position Control ring adopts proportional controller, and proportional controller numerical value is made as K _θ, the closed loop transfer function, of position ring is:

$G_p\left(s\right)=\frac{\mathrm{\&theta;}}{{\mathrm{\&theta;}}^{*}}=\frac{K_{\mathrm{\&theta;}}{K}_W/{\mathrm{\&tau;}}_W}{s^2+s/{\mathrm{\&tau;}}_W+K_{\mathrm{\&theta;}}{K}_W/{\mathrm{\&tau;}}_W}---\left(3\right)$

θ is a position feedback, θ ^*Given for the position, establish the position ring gain and be K _p=K _θK _W, then (3) formula is:

Wherein, $\mathrm{\&xi;}=\frac{1}{2}\sqrt{\frac{1}{K_p{\mathrm{\&tau;}}_W}},$ ${\mathrm{\&omega;}}_n=\sqrt{\frac{K_p}{{\mathrm{\&tau;}}_W}}$

Make positional servosystem be in critical damping state or underdamping state, the cut-off frequency f of speed link after proofreading and correct _W=1/ τ _WAfter determining, determine by ξ 〉=1: K _p≤ 1/ (4 τ _W), K _p=1/ (4 τ _W) be that the optimal location control loop gains.

Described opening-closing die motor and push-out motor are controlled comprises the steps:

The 1st step, adopt five twisting mould hyperbolic elbow clampings and crank block ejecting mechanism, according to the shifting formwork speed characteristics and the reinforcement characteristic of the folding mold process of double curved elbow mechanism, determine ball-screw that mold closing mechanism and liftout attachment are selected for use and opening-closing die motor, push-out motor;

The 2nd step, according to the load characteristic and the technological requirement of opening-closing die motor, push-out motor, perfect mould safeguard measure is controlled and be provided with to opening-closing die motor and push-out motor, comprising:

(1) in the matched moulds process, at first carry out matched moulds fast with low-pressure, when moving platen and solid plate near the time, automatically switch to the low speed matched moulds, in determining die cavity, behind the no foreign matter, switch to high pressure once more with the mould closure; In the matched moulds process, overflow for preventing the mould material, need apply bigger mold clamping force, this process opening-closing die motor adopts Torque Control;

(2) in the die sinking process, will guarantee that at first injection-moulded plastic part cooling die cavity surface breaks away from the position of guide pillar, moving platen at the uniform velocity moves quick die sinking then, and moving platen stops at a slow speed near the start position of moving platen the time;

(3) eject speed by the rotating speed adjustment of regulating push-out motor, guarantee accurately and reposefully goods in the mould to be ejected;

Ball-screw and opening-closing die motor, push-out motor that definite mold closing mechanism in described the 1st step and liftout attachment are selected for use are meant: 1. according to the translation working condition of five twisting mould hyperbolic elbow clampings, determine the ball-screw diameter of axle, helical pitch, leading screw length, the leading screw diameter of axle and accuracy class; 2. take all factors into consideration the recently selected opening-closing die motor of transmission, the push-out motor of required clamp force, shifting formwork speed, stroke ratio, ball-screw helical pitch, belt drive unit.

In described the 2nd step (1) really in the cover half chamber no foreign matter be meant that between detection zone of set positions the variation by detection opening-closing die motor load current has not transfinite and defines clear near solid plate;

Guarantee in described the 2nd step (2) that position that injection-moulded plastic part cooling die cavity surface breaks away from guide pillar is meant that with described set positions be the position of guide pillar when contacting with the mould of fixation side;

Matched moulds process in described the 2nd step (1) comprises:

1., move to the matched moulds shift position, be called 1 section of closure pressing speed from the die sinking end position;

2., move to the mould protective position, being called closure pressing speed is 2 sections, and this section is the high velocity, low pressure motion from the matched moulds shift position;

3., move to the mould contact position from the mould protective position, be called 3 sections of closure pressing speeds, this section is a mold protection, the usual current curve increase of current ratio appears if current sensor monitors this section matched moulds, being considered as die face has remaining plastics not to be removed, and the matched moulds process stops and die sinking immediately;

4., move to mould from mold protection and close tightly, apply the maximum pressure locked mode;

The shifting formwork speed of described the 2nd step die sinking and mold closing process draws as follows:

1., moving platen stroke

According to structural analysis, the shift motion S of moving platen _mThe displacement of can hinged-support B ordering characterizes:

$S_m={\mathrm{<figure-callout\; id="0"\; label="L\; AB"\; filenames="HSA00000220249300031.png"\; state="\{\{state\}\}">L</figure-callout>}}_{{\mathrm{AB}}_{}}\cos {\mathrm{\&gamma;}}_0-{\mathrm{<figure-callout\; id="1"\; label="L\; AB"\; filenames="HSA00000220249300031.png"\; state="\{\{state\}\}">L</figure-callout>}}_{{\mathrm{AB}}_{}}\cos {\mathrm{\&gamma;}}_1---\left(4\right)$

In the formula (4) It is the line of centres at whole lock position hinge A, B.

$L_{{\mathrm{AB}}_O}={\mathrm{<figure-callout\; id="1"\; label="L"\; filenames="HSA00000220249300031.png"\; state="\{\{state\}\}">L</figure-callout>}}_1+L_2---\left(5\right)$

${\mathrm{<figure-callout\; id="1"\; label="L\; AB"\; filenames="HSA00000220249300031.png"\; state="\{\{state\}\}">L</figure-callout>}}_{{\mathrm{AB}}_{}}={\mathrm{<figure-callout\; id="1"\; label="L"\; filenames="HSA00000220249300031.png"\; state="\{\{state\}\}">L</figure-callout>}}_1\cos {\mathrm{\&alpha;}}_1+{\mathrm{<figure-callout\; id="2"\; label="L"\; filenames="HSA00000220249300011.png,HSA00000220249300031.png"\; state="\{\{state\}\}">L</figure-callout>}}_2\cos {\mathrm{\&beta;}}_1---\left(6\right)$

Elbow length is than λ=L ₁/ L ₂, according to the law of sines

Can get thus $S_m=L_1(1-\cos {\mathrm{\&alpha;}}_1+\frac{\sqrt{1-{\mathrm{\&lambda;}}^2{\mathrm{<figure-callout\; id="2"\; label="sin"\; filenames="HSA00000220249300011.png,HSA00000220249300031.png"\; state="\{\{state\}\}">sin</figure-callout>}}^2{\mathrm{\&alpha;}}_1}}{\mathrm{\&lambda;}})---\left(7\right)$

${\mathrm{\&alpha;}}_1={\cos }^{-1}[1-\frac{S_m(2L_1-S_m\mathrm{\&lambda;})}{2L_1({\mathrm{<figure-callout\; id="1"\; label="L"\; filenames="HSA00000220249300031.png"\; state="\{\{state\}\}">L</figure-callout>}}_1+\mathrm{\&lambda;}{L}_1-\mathrm{\&lambda;}{S}_m)}]---\left(8\right)$

2., piston rod stroke S _gWith stroke ratio K _S

The piston rod stroke is a term of continuing to use the fluid pressure type mold closing mechanism, in motor-driven mold closing mechanism, and S _gThe stroke of expression crosshead characterizes with the amount of movement that cuts with scissors E on the crosshead:

The template stroke is called stroke ratio K with the ratio of crosshead stroke _S=S _M/ S _g(12)

K _SReflect the ratio of shifting formwork speed and crosshead translational speed, and reflected the energy consumption of board;

3., shifting formwork speed V _mWith velocity variation coefficient K _V

The shifting formwork speed of Type of Toggle Clamping Units is for can control shifting formwork speed, if ignore friction loss, according to principle of conservation of energy, the power that the power that clamping is imported should equal to export promptly

P _B·V _B＝P _M·V _M (13)

So the template translational speed can get

The utility model has following advantage and effect with respect to prior art:

1, the utility model relies on four servomotors of dsp controller to control, can realize the efficiency optimizationization of injection moulding process, not only melten gel metering quality is good, melten gel measuring accuracy height, the folding mold process had both considered to shorten the time of lost motion, considered the buffering requirement of mould opening-closing process again, had avoided the defective of excessive limit of goods or goods precise decreasing, and simple in structure, easy for installation, transmission accuracy is high, noise is low.

2, by control system of the present utility model and control method, the technological process that realizes electric injection molding machine is driven by six individual motor finishes the injection moulding function, drive injection machine the control of folding mould, melten gel control, injection control, holding pressure control, eject control, penetrate platform and move and control and mode transfer is controlled.Compare with hydraulic injection molding machine, can operate simultaneously two technologies.Can eject control as die sinking, melten gel arts demand melten gel motor cooperates with the injection motor, or the like, can save the time three/one-period than hydraulic injection molding machine injection product.

Description of drawings

Fig. 1 is the structural representation of full electric injection molding machine of the present utility model;

Wherein: 1. ball-screw 2. ball screws 3. move support plate 4. melten gel servomotors 5. cog belts 6. screw rods 7. ball-screws 8. and eject servomotor 9. ball-screws 10. locked mode servomotors 11. servomotor moments of torsion and control 12. cog belts, 13. pressure sensors, 14. injection servomotors 15. and transfer slide leading screws 16. to transfer slide Y motors 17. to loose core to watch motor 18. ball screws 19. to crank arm to stretch cautious 20. 21. ball screws, 22. mode transfer Y motors, the 23 mode transfer screws of cranking arm;

Fig. 2 is the utility model full electric injection molding machine Shooting Technique flow process;

Fig. 3 is full electric injection molding machine servomotor of the present utility model and PLC control system structured flowchart;

Fig. 4 is the general construction block diagram of full electric injection molding machine control system of the present utility model;

Fig. 5 is the input of I/O plate, the output point line map of PLC controller in the full electric injection molding machine of the present utility model;

Fig. 6 is the core control task block diagram of computer controller in the full electric injection molding machine of the present utility model;

Fig. 7 is the process cycles schematic diagram of full electric injection molding machine;

Fig. 8 is the motion schematic diagram of the double curved elbow mechanism that adopts of the clasp mould mechanism of full electric injection molding machine;

Fig. 9 is the control system of full electric injection molding machine and the concrete line block diagram of servomotor.

The specific embodiment

The utility model is described in further detail below in conjunction with drawings and Examples.But embodiment of the present utility model is not limited thereto.

A general injection (mo(u)lding) machine mainly comprises four major parts: injection portion, matched moulds part, servomotor dynamical system, computer panel control system.

Electric injection molding machine is to use AC servomotor, is equipped with the injection machine that components and parts such as ball-screw, profile of tooth belt wheel drive each mechanism, and basic characteristics are that all driver modules are electrodynamic type entirely.The full electric type injection machine is the main type of electric injection molding machine, and each mechanism of each mechanism in its injection moulding apparatus (inject, plastify, measure and move seat etc.) and mold closing mechanism (folding mould, locked mode, eject etc.) all adopts Motor Drive.

The main effect of penetrating driving mechanism is to make plastics plastify into molten condition, and with enough pressure and speed certain melt is annotated in the die cavity.Therefore, it is good that injection device should have plasticizing, measures accurate performance, and can provide pressure and speed to melt when injection.Injection device generally is made up of plasticizing parts (rubber melting cylinder, spiral shell skewer, nozzle or the like), hopper, metering device and screw actuator and injection etc.

Penetrate driving mechanism and make the screw rod forward-reverse.By the rotation of AC servomotor and the effect of synchronous belt, drive the roller bearing screw mandrel, the roller bearing screw mandrel is converted into rectilinear motion to it, screw rod is advanced or retreats.It is to make plasticized resin be filled into mechanism in the mould from nozzle.

Screw rod melten gel mechanism makes the screw rod revolution by the rotation of AC servomotor and the effect of synchronous belt, measures.Resin in the barrel, along with the screw rod revolution, the phase mutual friction between the resin has produced heat, and owing to the heat transfer of material tube heater, hard resin is melted becomes the state that can penetrate simultaneously.

Clamping mechanism is to guarantee the mould reliably closing and realize the mould switching motion, and ejects goods, i.e. the workpiece of moulding goods.Because in when injection, the melt that enters in the die cavity also has certain pressure, this just requires mold closing mechanism to give mould with the enough tight power of closing, and is opened at the pressure bed die of melt preventing, thereby causes overflow limit or make the goods precise decreasing of goods.Mold closing mechanism mainly is made up of template, pull bar (brother woods post), clamping (as the machine hinge), goods liftout attachment and safety door, mode transfer device etc.

By the rotation of AC servomotor and the effect of timing belt pulley, drive ball screw, mould is opened or closed.Penetrate the moving by gear motor control of ejecting base in the pedestal actuating mechanism, the contact force of mould is that detection springs stress is learnt in addition.Ejecting mechanism by the AC servomotor rotation and the effect of synchronous belt, drive the ball driving screw, liftout plate advanced or retreat, finish the process that ejects of moulding product.The thick guiding mechanism of mould be by gear motor rotation, critically keep the depth of parallelism and the locked mode equilibrium of forces of mill.

Injection (mo(u)lding) machine is by the plastics fusion, mold closure, be injected into mould, pressure keeps, goods solidify, the continuous flow procedure that operations such as die sinking taking-up goods are formed, motor and electric then be in order to guarantee that injection (mo(u)lding) machine is by the predetermined requirement (pressure of technical process, speed, temperature, time and position) and operation program, carry out work and the power and the control system that are provided with like clockwork. power section mainly contains servomotor, servo-driver (electric machine controller), computer control panel (control action parameter), the screw rod temperature controller, the mode transfer motor, penetrate platform displacement motor or the like.

The order of control system control injection cycle and maintenance process temperature, time, pressure and speed are in setting value (process control).Electric part mainly is made up of controls such as power, operation program and heating.

Be illustrated in figure 1 as the utility model motor injection machine mechanism map, comprise A, B two parts:

A part: comprise that melten gel, injection, slide unit displacement adjust three parts and form.When melten gel servomotor 4 rotates, drive screw rod 6 end faces by cog belt, promoting the melten gel screw rod is moved to the left, act on pressure sensor 13 ring flanges, according to the predefined smelting glue back pressure power P back of the body, when P＞P is unlucky, injection servomotor 14 rotates, drive ball-screw by the profile of tooth belt wheel and rotate (leading screw axial restraint) and make mobile support plate 3, reach the smelting glue back pressure power P back of the body with balance and be stabilized in setting value to left dislocation.[in the melten gel process, the rotating speed of melten gel servomotor 4 under the melten gel speed of setting moves.Injection servomotor 14 is that the P back of the body of following the tracks of pressure sensor changes and increases or reduce, and makes the analog signal conversion of output become digital pulse signal to rotate for injection servomotor 14 stablize P to carry on the back].In the overall process of melten gel since technology need melten gel the time to control.Screw speed can divide the N level, switching position N-1 level, and back pressure can divide the X-1 level [in the melten gel process, be the high-voltage lock mould moulding that is in after the injection, cooling, die sinking, eject pickup, quick matched moulds, high-voltage lock mould], high-voltage lock mould is finished behind the melten gel, carry out injection, it is controlled to be the constant speed level pressure, X step velocity+1 stage pressure control, switch the control of X level pressurize N stage pressure, the time is provided with the N-1 level].

The injection course of work: injection servomotor 14 starts two ball-screws 1 and rotates, and moving mobile support plate 3 lead-screws 6 of holder advance.Pressure sensor 13 pressure-bearings, then the definite value of penetrating of injection pressure compares.When P penetrates when being greater than or less than the P predetermined value, injection servomotor 14 is followed the tracks of to rotate to reach and is stablized P and penetrate.

B part: finish folding mould and working of plastics and eject.Its operating principle is that servomotor 11 drives ball-screw 9 by cog belt, screw 21 straight line forward moves the cross that promotes to crank arm and stretches, bent line arm promotes moving platen mould is locked, after finishing locked mode, must guarantee to crank arm to stretch, stretch test point 19 when dispatching from the factory manufacturer to determine, according to the different available mode transfer motor Y22 of mould total thickness B, mode transfer screw 23 changes.The pressure of clamp force P lock is converted into Motor torque to clamp force vertical compression power (ton) by the control of servomotor 11 usefulness moments of torsion, the control of Motor torque available current.Just pressure and electric current are linear, detect the Current Control motor and stop.

Eject plastic servomotor 8, after die sinking, start, can set the X level and eject to shake and eject (N 〉=1).

In sum, controlled 4 of full motor injection moulding reaches the high efficiency injection moulding with 4 of controls or with control 2 (4,14).

Be illustrated in figure 2 as the utility model electric injection molding machine Shooting Technique flow process, the technological process of electric injection molding machine is to finish the injection moulding function by six motor-driven, these six motors drive respectively injection machine the control of folding mould, melten gel control, injection control, holding pressure control, eject control, penetrate platform and move control, and mode transfer control.Some of them actions is can multiple action, can eject simultaneously as die sinking, and locked mode can be penetrated platform and move or the like.All action is finished by the cooperation of injection machine computer controller.

The operation program of injection machine: nozzle advances → injects → pressurize → preformed → retraction → nozzle retreats → cool off → die sinking → eject → withdraw of the needle → open the door → close the door → and matched moulds → nozzle advances.

1, injection machine operation item: the injection machine operation is checked electric control cabinet, servo electrical machinery system and three aspects of mechanical lubrication device by the operation of panel supervisory keyboard.Carry out injection process action, reinforced action, injection pressure, injection speed respectively, eject the selection of pattern, the monitoring of each section of barrel temperature and electric current, voltage, the adjusting of injection pressure and back pressure pressure etc.

2, injection process Action Selection: but general both manual operations of injection machine, also can semi-automatic and full automatic working.Manual operation is in a production cycle, and each action is all stirred console switch by the operator and realized.Generally when the test-run a machine mode transfer, just select for use.Machine can be finished the action of a work period automatically during semi-automatic operation, and the back operator must draw back safety door but each production cycle finishes, and takes off workpiece, shuts safety door again, and machine can be to continue the production of next cycle.Injection machine can enter the next work period automatically during full automatic working after the action of finishing a work period.In normal continuous operation process, need not shut down and control and adjust.The course of action of every injection machine can roughly be expressed as basic cyclic program shown in Figure 7:

(1) mold closing and close tight

The molding cycle of injection machine is generally when mould begins closure.Mould at first carries out matched moulds fast with low-pressure, when moving platen (two plates) and solid plate (plate) near the time, the dynamical system of matched moulds should change and switches to low pressure, low speed is when no foreign matter exists in determining die cavity, switches to high pressure again and mould is closed tightly.

(2) injection device reach and injection

Confirming that mould reaches the desired tight power of closing, the injection device reach is fitted nozzle and mould, after nozzle and mould are finished applying, just can start injecting motor, then the screw rod that joins with motor, then with high-voltage high-speed with the melt injection die cavity of producing.This moment, screw head acted on the injection pressure on the melt, was called injection pressure again.

(3) pressure keeps (pressurize)

Inject the melt of die cavity, because the cooling effect of low temperature mould produces the melt that injects in the die cavity and shrinks, for making the goods of quality densification, so also need keep certain pressure to carry out feeding to melt when cooling.The pressure of screw acting this moment on melt is referred to as dwell pressure, and screw rod has a spot of reach when pressurize.

(4) goods cooling and preplasticizing

When the melt that proceeds to die cavity when pressurize loses cast gate backflow possibility (cast gate sealing), the dwell pressure of injecting motor can shed (this moment, the high pressure of matched moulds motor also can be removed), makes goods cooling and shaping in mould.At this moment, screw rod rotates under the driving of motor, will be fed forward from the sizing material of the granular or powdery of hopper, and makes its plasticizing.Because the effect of screw head melting material pressure produces screw rod again and retreats when rotating.Screw rod is the amount of moving after when plasticizing, has promptly represented the long-pending amount of the melt that screw head accumulated.When screw rod return back to variable, screw rod promptly stopped operating, and prepared injection next time.Goods coolings is logical in time with spiro rod plasticizing to be overlapping, in the ordinary course of things, requires the spiro rod plasticizing metering time will be less than goods cool times.

(5) injection device retreats with die sinking and ejects goods

After the spiro rod plasticizing metering finishes, be unlikely because of long-time and cold mould contacts causes such as forming cold burden in order to make nozzle, often need nozzle to withdraw mould, promptly injection device retreats, and whether this action is carried out or program successively, and machine is all available.Melt in the die cavity is behind cooling and shaping, and mold closing mechanism i.e. mould in the ranks, and ejects goods automatically.

(6) operation of machine

1. manual state

Manually be whether each action of debugging injection machine meets the injection moulding requirement.According to injection moulding actuation cycle technological requirement, manually folding mould, She Tai advance, melten gel, action such as inject, eject and independently finish.

2. semi-automatic state

Manually exercises normal after, can carry out debugging semi-automatic state under, should be with the knob button of " ON " and " OFF " and toggle switch at " ON " in case move back to and move to some extent when manual.Knob button is in " semi-automatic " position and shut safety door, and the locked mode action reaches by the parameter of setting and begins to carry out periodic duty.This mode of operation is applicable to that product is penetrated in injection test and some can not use full-automatic product processed.Working condition is, when shutting safe door knob LSI and leave the action of LS-16 locked mode and carry out, then safety door can draw back to the locked mode release, and whole circulation to thimble action stops.

3. full-automatic state

Semi-automatic debugging is normal when manually reaching, and button pushes automatically.Shut safety door, then automatically begin.

7, temperature control

With the temperature thermocouple is temperature element, and being equipped with the thermometric millivoltmeter becomes temperature regulating device, the break-make of commander barrel and mould electric heating coil electric current, fixedly each section of barrel temperature and mold temperature selectively.

Be illustrated in figure 3 as the utility model control system structured flowchart, include computer controller, folding mould (locked mode) servomotor and DSP servo-driver 1, control injection machine clasp mould mechanism; Injection servomotor and DSP servo-driver 2; Melten gel pressurize servomotor and DSP servo-driver 3 are controlled the injection machine machine barrel respectively and are made screw rod toward the injection molding filled plastics; Eject servomotor and DSP servo-driver 4, the control injection machine ejects ejecting mechanism.Injection machine is penetrated platform mechanism and injection machine is penetrated platform aim at the mold runner mouth, penetrates the platform mobile motor and penetrates platform mechanism by frequency-variable controller 1 control and move to the die cavity mouth.Mould adjusting mechanism is to make the mould matched moulds produce clamp force by mode transfer frequency-variable controller 2 control mode transfer motors.

In specific implementation process, the utility model adopts electric injection molding machine control system structure as shown in Figure 4, comprises interconnective injection machine computer controller, LCD display module, Keysheet module, USB interface and network interface, CAN communication interface, 485 communication interfaces, four TMS32OF28335 servo-drivers, melten gel servomotor, injection servomotor, locked mode servomotors, ejects servomotor, mode transfer variable-frequency motor controller, penetrates platform variable-frequency motor controller and PLC controller.Realize that above-mentioned injection moulding function always has six motors.Wherein folding mould, colloidal sol and pressurize, injection, eject control and adopt 4 AC permanent magnet synchronous motors, penetrate that platform moves and 2 common variable-frequency motors are adopted in mode transfer control.By the disclosed DSP servo controller control of the utility model, common variable-frequency motor adopts two frequency-variable controller controls to AC permanent magnet synchronous motor respectively.Adopt high-speed CAN bus to realize communication between last level controller and the next servo-control system.

The host computer computer adopts the main control chip of AMD GeodeTM LX800, is that operating system makes up whole master system with embedded WINDOWS CE6.0 version.And disposed 10 cun LCD displays, and the keyboard input module, the communication interface of PLC, servo-driver communication interfaces etc. have also been reserved USB interface and Ethernet interface.The servo-drive controller adopts the TMS320F28335 of TI company as acp chip, drives the melten gel motor of injection machine, the injection motor, and the locked mode motor, push-out motor, this chip is integrated multiple advanced person's peripheral hardware is for the application of bi-motor provides good platform.Control when therefore system adopts two controllers to realize four motors.Driver is realized torque, speed and the Position Control of motor by gathering three-phase current and motor rotor speed by related algorithm in DSP.The main circuit of this servo-drive system adopts typical voltage-source type ac-dc-ac inverter circuit, and main power circuit is made of rectification circuit, filter circuit and inverter circuit.。Adopt frequency converter as the controller of penetrating platform motor and mode transfer motor simultaneously, PLC is responsible for all input and output amounts of whole injection machine.

The closed-loop control of electric injection molding machine servo-driver requires:

Injection servomotor: speed closed loop control, moment of torsion closed-loop control (cooperating), angle (position) closed-loop control, stall moment of torsion output control with pressure sensor;

Melten gel servomotor: speed closed loop control;

Locked mode servomotor: speed closed loop control, angle (position) closed-loop control, the closed-loop control of specified angle internal torque;

Eject servomotor: speed closed loop control, angle (position) closed-loop control.

Servo-drive control unit interface function: electromotor brake monitoring function, 2 analog quantity inputs (band is isolated), code-disc data signal output (band is isolated), 4 marking signal interfaces (band is isolated), position, speed, Torque Control, synchronizing function, response speed, feedback time 62.5ms, CAN interface (band is isolated) or TCP/IP EBI.

Remove four main servomotors and adopt outside the DSP control, mode transfer motor and penetrate the platform motor and adopt PLC control.Simultaneously, the input and output of whole system all are responsible for by PLC.Comprise 14 tunnel analog quantity input, 8 tunnel PWM output, the switching value input of No. 53 injection machines, 60 tunnel injection machine switching value output.PLC control injection moulding operation program table is as shown in table 1 in the utility model, wherein: the state when the input switch amount is each release.

Table 1

Injection machine switch input terminal (32 inputs) is as shown in table 2:

Table 2:

Injection machine output switching terminal (output of 1-32 point transistor, the output of 33-48 point relay) is as shown in table 3:

Table 3

Injection machine analog quantity input/output terminal is as shown in table 4:

Table 4:

The contact of last level controlling system and the next servo-control system is mainly communicated by letter by CAN and is finished, the major function of CAN communication is: when carrying out certain action, last level controller sends instruction by the CAN bus and gives corresponding electric machine controller, after this controller receives instruction, carry out action according to command request, and the data (such as size of current) that need in the implementation to add up are sent.

Be different from traditional hydraulic injection molding machine, each action of all-electric precise injection machine adopts motor to control respectively, can realize " synchronization action ".The mode of this independent control shows as the tasks that traditional sequentially-operating control is separated into a plurality of independent controls in the software design, comprising: die sinking, matched moulds, melten gel, injection, pressurize, eject, penetrate the platform reach, penetrate platform and eight independent tasks such as retreat.Be illustrated in figure 6 as the core missions of computerized control system; these core missions are to adopt to embed real time operating system Windows CE exploitation in software architecture; system is divided into a plurality of independent tasks; on real-time system, the whole procedure framework is set at real-time a plurality of tasks interrupt scheduling mechanism; comprise injection device control (back pressure sensor; code-disc); melten gel (back pressure sensor; code-disc); die sinking (screw mandrel stroke; open safety door); matched moulds (closes safety door; the code-disc clamping mechanism); the thimble motor transmission mechanism (is opened; matched moulds; close safety door); penetrating platform moves control and (penetrates 2 of platform limit switches; penetrate platform displacement electron chi); the mode transfer structure is (before the accent; behind the accent; 2 of limit switches; automatic mold-adjustment control, manually mode transfer); temperature control (screw rod; barrel; mould); the lubricating oil motor regularly refuels (to be opened; matched moulds; frequency injection); the online Self-learning control of product property is set up; the SPC control of precise injection molding goods; injection pressure; the position; time control curve and CAN bus network.Specifically by forming with lower module:

(1) safety door, urgent button control module task: SecuPrt_Task priority: 9

(2) injection motor control module task: MotoJet_Task priority: 10

(3) colloidal sol motor control module task: MotoFuse_Task priority: 11

(4) opening and closing mould motor control module task: MouldCtrl_Task priority: 12

(5) push-out motor control module task: MotoPop_Task priority: 13

(6) penetrate platform mobile motor control task: MotoMoveTask priority: 14

(7) mode transfer motor control module task: MouldAdj_Task priority: 15

(8) temperature control modules task: TempCtrl_Task priority: 16

(9) communication control module task: Comu_Task priority: 17

(10) keyboard input module task: KeyBoard_Task priority: 18

(11) window shows certain piece task of control: UI_Task priority: 19

(12) port interrupts interrupt service routine: Comu_ISP

(13) clock interrupts interrupt service routine: Time_ISP

(14) keyboard interrupt interrupt service routine: KeyBoard_ISP

(15) urgent button interrupts interrupt service routine: WarnKey_ISP

Flow process according to Fig. 2 sets, adopt following control method to control to four servomotors:

The first step, the mode of operation of the servomotor of selection full electric injection molding machine: manual, semi or fully automatic;

Second step started the control method of servo control system according to selected pattern, and wherein manual mode is meant according to injection moulding actuation cycle technological requirement, and manually input parameter is controlled independently that folding mould, She Tai advance, melten gel, injected, ejects action; The semi-automatic work pattern is meant according to injection moulding action technological requirement, finishes the single cycle action by servo control system according to control method; The fully automatic working pattern is meant according to injection moulding action technological requirement, finishes repeatedly do action by servo control system according to the flow process of single cycle action.

Finishing single cycle action according to control method and comprise the steps: in second step

The I step, the closed safe door;

The II step, the injection servomotor is controlled, split the matched moulds servomotor simultaneously and carry out matched moulds control;

In the III step, melten gel pressurize servomotor is carried out holding pressure control;

The IV step, melten gel pressurize servomotor is carried out melten gel control, split the matched moulds servomotor simultaneously and carry out die sinking control and eject control ejecting servomotor;

The V step, open safety door, finish.

The injection servomotor is connected as shown in Figure 9 with the concrete of controller with melten gel pressurize motor, the injection servomotor is controlled and melten gel pressurize servomotor controlled be meant:

The injection process is: the melten gel motor is not worked, the injection motor starts, driving the injection nut rotates, and injection motor and injection nut location do not move, the injection nut drives the ball screw forward impelling, ball screw lead-screw, melten gel nut, melten gel motor advance simultaneously, finish until the injection process, and the injection motor is shut down;

The melten gel process is:

I step: the melten gel motor starts, and melten gel driven by motor melten gel nut rotates, and the melten gel nut drives screw rod and rotates, and bearing is equipped with in screw rod and ball screw junction, makes screw rod freely rotate and can not drive the ball screw rotation;

The ii step: screw rod pushes limit heating and melting material by rotation forward with the material limit, material is constantly carried toward screw head, the fused materials that accumulates in the material stock district of machine barrel produces certain pressure, pressure is increasing, lead-screw, but because the ball screw fastening screw, screw rod can not directly retreat, but make the pressure between screw rod and the ball screw increasing, at this moment, the pressure sensor that is positioned at screw rod and ball screw junction is sent to dsp controller to pressure measuring value;

The iii step: dsp controller and pressure set points compare;

The iv step: when the measured value of pressure sensor surpasses setting value, dsp controller control injection motor and injection nut begin counter-rotating, and injection motor and injection nut location do not move, ball screw shrinks back according to the speed of setting, screw rod also shrinks back, melten gel nut and melten gel motor drive screw on one side also shrink back on one side, but ball screw keeps certain pressure to screw rod;

V step: until satisfying the displacement of setting that retreats, finish resetting of injection volume and ball screw, injection motor, melten gel motor are shut down, for injection is next time prepared;

In the melten gel process: the movement function equation that screw rod retreats is: M: the gross weight of screw rod, melten gel nut, melten gel motor; G: acceleration of gravity; V: screw rod astern speed; F _a: the pressure that fused materials produces; F _B: the resistance of ball screw; F _L: the reaction force of fused materials; F: frictional force.

The current relationship of melten gel pressurize motor and injection motor is:

The electric current loop open-loop transfer function is:

K _vBe the contravarianter voltage multiplication factor of outside PWM unit, K _mBe current feedback coefficient, T _vBe inverter time constant, T _v=1/f _v, f _vBe the inverter operating frequency, s is a differential, and two armature loops are made up of resistance R and inductance L, are first order inertial loop, T _OiBe the current sample time constant filter,

Wherein, T _OiAnd T _vConstant between being hour, equivalence is a time constant T _Ov=T _Oi+ T _v, T again _L=L/R is an armature loop time constant, and (1) formula equivalence is:

The pi regulator of motor is current correction the I type system with better dynamic property, and the adjuster transfer function is

K _p, τ _cBe respectively the proportionality coefficient and the integration time constant of pi regulator,

With the limit of the large time constant of cancellation at the zero point controlled device of electric current loop pi regulator, get τ _c=L/R=T _L, therefore the electric current loop open-loop transfer function after pi regulator is proofreaied and correct is

(2) formula is reduced to a typical I type system:

K=K wherein _pK _v/ (R τ _c);

Then the electric current loop closed loop transfer function, is:

$C\left(s\right)=\frac{G\left(s\right)}{1+G\left(s\right)}$

$=\frac{K_v{K}_p{K}_m}{{\mathrm{\&tau;}}_{c}s(T_{\mathrm{ov}}s+1)+K_v{K}_p{K}_m}$

$=\frac{K}{s(T_{\mathrm{ov}}s+1)+K}$

$=\frac{{{\mathrm{\&omega;}}_n}^2}{{\mathrm{<figure-callout\; id="2"\; label="s"\; filenames="HSA00000220249300011.png,HSA00000220249300031.png"\; state="\{\{state\}\}">s</figure-callout>}}^2+2\mathrm{\&xi;}{\mathrm{\&omega;}}_{n}s+{{\mathrm{\&omega;}}_{\mathrm{<figure-callout\; id="2"\; label="n"\; filenames="HSA00000220249300011.png,HSA00000220249300031.png"\; state="\{\{state\}\}">n</figure-callout>}}}^2}$

ω n is a cut-off frequency, according to the second-order system optimal performance index, gets damping ratio ξ=0.707, promptly

Try to achieve K, again τ _c=L/R=T _L, determine K _p, τ _c

Described electric current loop is the interior ring of speed ring, under the situation of the transfer function that obtains electric current loop,

The speed ring closed loop transfer function:

β is a voltage vector, K _FnBe speed feedback coefficient, T _mBe motor electromechanical time constant, K _ΦBe the motor coefficient of potential,

T _OnBe the speed feedback time constant filter,

T _lAnd T _OnConstant between being hour, equivalence is a time constant T _Fs=T _l+ T _OnInertial element, then speed ring control object is:

$C_i\left(s\right)=\frac{K_{l}R{K}_{\mathrm{fn}}}{T_m{K}_{\mathrm{\&Phi;}}s(T_{\mathrm{fs}}s+1)}=\frac{K_{l}R{K}_{\mathrm{fn}}/T_m{K}_{\mathrm{\&Phi;}}}{s(T_{\mathrm{fs}}s+1)}=\frac{K_{\mathrm{on}}}{s(T_{\mathrm{fs}}s+1)}$

Speed ring proofreaied and correct be typical II type system, the speed ring adjuster is a pi regulator, and transfer function is

Speed ring open-loop transfer function after pi regulator is regulated is:

$C_s\left(s\right)=\frac{K_{\mathrm{ps}}({\mathrm{\&tau;}}_{s}s+1)K_c}{{\mathrm{\&tau;}}_{s}J{s}^2(2T_{\mathrm{fs}}s+1),}$

Kc is a proportionality coefficient, is definite value, and J is the rotor inertia of motor, is definite value,

After proofreading and correct through pi regulator, speed ring is a typical II type system, and the speed ring open-loop transfer function is:

Wherein, K _N=K _OnK _Ps/ τ _sBe speed ring open loop multiplication factor, definition open loop amplitude versus frequency characte Mid Frequency width is h=τ _s/ T _Fs, it is determining the dynamic performance index of typical II type system, h increases overshoot and reduces, but the adjusting time be not dull with the variation of h, the time of regulating when h=5 is the shortest, dynamic response is the fastest, selects suitable cut-off frequency ω again _n, calculate τ _sAnd K _Ps:

$\left\{\begin{array}{c}{\mathrm{\&tau;}}_s=h*T_{\mathrm{fs}}\\ K_{\mathrm{ps}}=\frac{h+1}{2h}*\frac{T_m{K}_{\mathrm{\&Phi;}}}{T_{\mathrm{fs}}{K}_{l}R{K}_{\mathrm{fn}}}\end{array}\right.$

The time cycle of described speed ring and gain are τ _WAnd K _W, the Position Control ring adopts proportional controller, and proportional controller numerical value is made as K _θ, the closed loop transfer function, of position ring is:

$G_p\left(s\right)=\frac{\mathrm{\&theta;}}{{\mathrm{\&theta;}}^{*}}=\frac{K_{\mathrm{\&theta;}}{K}_W/{\mathrm{\&tau;}}_W}{s^2+s/{\mathrm{\&tau;}}_W+K_{\mathrm{\&theta;}}{K}_W/{\mathrm{\&tau;}}_W}---\left(3\right)$

θ is a position feedback, θ ^*Given for the position, establish the position ring gain and be K _p=K _θK _W, then (3) formula is:

Wherein, $\mathrm{\&xi;}=\frac{1}{2}\sqrt{\frac{1}{K_p{\mathrm{\&tau;}}_W}},$ ${\mathrm{\&omega;}}_n=\sqrt{\frac{K_p}{{\mathrm{\&tau;}}_W}}$

Make positional servosystem be in critical damping state or underdamping state, the cut-off frequency f of speed link after proofreading and correct _W=1/ τ _WAfter determining, determine by ξ 〉=1: K _p≤ 1/ (4 τ _W), K _p=1/ (4 τ _W) be that the optimal location control loop gains.

The concrete line graph of opening-closing die motor and push-out motor and controller is controlled the opening-closing die motor push-out motor and to be comprised the steps: as shown in Figure 9

The 1st step, adopt five twisting mould hyperbolic elbow clampings and crank block ejecting mechanism, according to the shifting formwork speed characteristics and the reinforcement characteristic of the folding mold process of double curved elbow mechanism, determine ball-screw that mold closing mechanism and liftout attachment are selected for use and opening-closing die motor, push-out motor;

The 2nd step, according to the load characteristic and the technological requirement of opening-closing die motor, push-out motor, perfect mould safeguard measure is controlled and be provided with to opening-closing die motor and push-out motor, comprising:

(1) in the matched moulds process, at first carry out matched moulds fast with low-pressure, when moving platen and solid plate near the time, automatically switch to the low speed matched moulds, in determining die cavity, behind the no foreign matter, switch to high pressure once more with the mould closure; In the matched moulds process, overflow for preventing the mould material, need apply bigger mold clamping force, this process opening-closing die motor adopts Torque Control;

(2) in the die sinking process, will guarantee that at first injection-moulded plastic part cooling die cavity surface breaks away from the position of guide pillar, moving platen at the uniform velocity moves quick die sinking then, and moving platen stops at a slow speed near the start position of moving platen the time;

(3) eject speed by the rotating speed adjustment of regulating push-out motor, guarantee accurately and reposefully goods in the mould to be ejected;

1., according to the translation working condition of five twisting mould hyperbolic elbow clampings definite mold closing mechanism and liftout attachment ball-screw and opening-closing die motor, the push-out motor selected for use in described the 1st step are meant:, determine the ball-screw diameter of axle, helical pitch, leading screw length, the leading screw diameter of axle and accuracy class; 2. take all factors into consideration the recently selected opening-closing die motor of transmission, the push-out motor of required clamp force, shifting formwork speed, stroke ratio, ball-screw helical pitch, belt drive unit.

In described the 2nd step (1) really in the cover half chamber no foreign matter be meant that between detection zone of set positions the variation by detection opening-closing die motor load current has not transfinite and defines clear near solid plate;

Guarantee in described the 2nd step (2) that position that injection-moulded plastic part cooling die cavity surface breaks away from guide pillar is meant that with described set positions be the position of guide pillar when contacting with the mould of fixation side;

Matched moulds process in described the 2nd step (1) comprises:

1., move to the matched moulds shift position, be called 1 section of closure pressing speed from the die sinking end position;

2., move to the mould protective position, being called closure pressing speed is 2 sections, and this section is the high velocity, low pressure motion from the matched moulds shift position;

3., move to the mould contact position from the mould protective position, be called 3 sections of closure pressing speeds, this section is a mold protection, the usual current curve increase of current ratio appears if current sensor monitors this section matched moulds, being considered as die face has remaining plastics not to be removed, and the matched moulds process stops and die sinking immediately;

4., move to mould from mold protection and close tightly, apply the maximum pressure locked mode;

As shown in Figure 8, the shifting formwork speed of described the 2nd step die sinking and mold closing process draws as follows:

1., moving platen stroke

According to structural analysis, the shift motion S of moving platen _mThe displacement of can hinged-support B ordering characterizes:

$S_m={\mathrm{<figure-callout\; id="0"\; label="L\; AB"\; filenames="HSA00000220249300031.png"\; state="\{\{state\}\}">L</figure-callout>}}_{{\mathrm{AB}}_{}}\cos {\mathrm{\&gamma;}}_0-{\mathrm{<figure-callout\; id="1"\; label="L\; AB"\; filenames="HSA00000220249300031.png"\; state="\{\{state\}\}">L</figure-callout>}}_{{\mathrm{AB}}_{}}\cos {\mathrm{\&gamma;}}_1---\left(4\right)$

In the formula (4)

It is the line of centres at whole lock position hinge A, B.

$L_{{\mathrm{AB}}_O}={\mathrm{<figure-callout\; id="1"\; label="L"\; filenames="HSA00000220249300031.png"\; state="\{\{state\}\}">L</figure-callout>}}_1+L_2---\left(5\right)$

${\mathrm{<figure-callout\; id="1"\; label="L\; AB"\; filenames="HSA00000220249300031.png"\; state="\{\{state\}\}">L</figure-callout>}}_{{\mathrm{AB}}_{}}={\mathrm{<figure-callout\; id="1"\; label="L"\; filenames="HSA00000220249300031.png"\; state="\{\{state\}\}">L</figure-callout>}}_1\cos {\mathrm{\&alpha;}}_1+{\mathrm{<figure-callout\; id="2"\; label="L"\; filenames="HSA00000220249300011.png,HSA00000220249300031.png"\; state="\{\{state\}\}">L</figure-callout>}}_2\cos {\mathrm{\&beta;}}_1---\left(6\right)$

Elbow length is than λ=L ₁/ L ₂, according to the law of sines

Can get thus $S_m=L_1(1-\cos {\mathrm{\&alpha;}}_1+\frac{\sqrt{1-{\mathrm{\&lambda;}}^2{\mathrm{<figure-callout\; id="2"\; label="sin"\; filenames="HSA00000220249300011.png,HSA00000220249300031.png"\; state="\{\{state\}\}">sin</figure-callout>}}^2{\mathrm{\&alpha;}}_1}}{\mathrm{\&lambda;}})---\left(7\right)$

${\mathrm{\&alpha;}}_1={\cos }^{-1}[1-\frac{S_m(2L_1-S_m\mathrm{\&lambda;})}{2L_1({\mathrm{<figure-callout\; id="1"\; label="L"\; filenames="HSA00000220249300031.png"\; state="\{\{state\}\}">L</figure-callout>}}_1+\mathrm{\&lambda;}{L}_1-\mathrm{\&lambda;}{S}_m)}]---\left(8\right)$

2., piston rod stroke S _gWith stroke ratio K _S

The piston rod stroke is a term of continuing to use the fluid pressure type mold closing mechanism, in motor-driven mold closing mechanism, and S _gThe stroke of expression crosshead characterizes with the amount of movement that cuts with scissors E on the crosshead:

The template stroke is called stroke ratio K with the ratio of crosshead stroke _S=S _M/ S _g(12)

K _SReflect the ratio of shifting formwork speed and crosshead translational speed, and reflected the energy consumption of board;

3., shifting formwork speed V _mWith velocity variation coefficient K _V

The shifting formwork speed of Type of Toggle Clamping Units is for can control shifting formwork speed, if ignore friction loss, according to principle of conservation of energy, the power that the power that clamping is imported should equal to export promptly

P _B·V _B＝P _M·V _M (13)

So the template translational speed can get

By as above control, just can realize optimum control to full electric injection molding machine.

Embodiment only is the utility model preferred implementation; but embodiment of the present utility model is not restricted to the described embodiments; other any do not deviate from change, the modification done under spiritual essence of the present utility model and the principle, substitutes, combination, simplify; all should be the substitute mode of equivalence, be included within the protection domain of the present utility model.

Claims (4)

1. the servo control system of a full electric injection molding machine is characterized in that, comprises injection machine computer controller, servomotor controller and PLC controller; Described computer controller is connected with servomotor controller by the CAN bus, and described servomotor controller is connected with servomotor, and described computer controller is connected with the PLC controller; Described servomotor controller is meant folding mould servomotor controller, injection servomotor controller, melten gel pressurize servomotor controller and ejects servomotor controller; Described servomotor is meant folding mould servomotor, injection servomotor, melten gel pressurize servomotor and ejects servomotor.

2. the servo control system of full electric injection molding machine according to claim 1 is characterized in that, also comprises the LCD display module, Keysheet module, the ethernet control chip that are connected with described injection machine computer controller respectively; Described injection machine computer controller adopts the AMD microprocessor, and described servomotor controller adopts dsp controller.

3. the servo control system of full electric injection molding machine according to claim 2, it is characterized in that, in described injection servomotor controller and the melten gel pressurize servomotor controller, the SCI module of described dsp controller connects pressure sensor, the JTAG module of dsp controller connects control emulator LED lamp, the I/O module of dsp controller connects control warning output location and finishes signal LED lamp, 2 EVA/B modules of dsp controller connect outside PWM unit, outside PWM unit by the IPM power driving device respectively with the injection servomotor, melten gel pressurize servomotor connects, injection servomotor and melten gel pressurize motor are given the ADC module feedback current signal of dsp controller respectively by current sensor, injection servomotor and melten gel pressurize servomotor are given the QEP module feedback signal of dsp controller respectively by code-disc.

4. the servo control system of full electric injection molding machine according to claim 2, it is characterized in that, described folding mould servomotor controller and ejecting in the servomotor controller, an output of dsp controller is by its CAN bus communication module that carries, jtag interface is connected respectively to injection machine computer controller and emulator, another output connects IPM power driving device and servomotor successively by the task manager EVA/B that it carries, described servomotor is connected to the analog-to-digital conversion module ADC of chip by current sensor, and described servomotor also connects the orthogonal encoder unit QEP of chip by code-disc; Described servomotor is meant opening-closing die motor and push-out motor.

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