CN202528404U - Control system for injection molding machine - Google Patents
Control system for injection molding machine Download PDFInfo
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- CN202528404U CN202528404U CN2012201228153U CN201220122815U CN202528404U CN 202528404 U CN202528404 U CN 202528404U CN 2012201228153 U CN2012201228153 U CN 2012201228153U CN 201220122815 U CN201220122815 U CN 201220122815U CN 202528404 U CN202528404 U CN 202528404U
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Abstract
The utility model discloses a control system for an injection molding machine. The control system comprises a controller for the injection molding machine, a servo driver, a servo motor, a quantitative oil pump for providing pressure to a hydraulic system, pressure sensors, and a rotational speed sensor. The control system is characterized in that a digital communication protocol is established between the controller for the injection molding machine and the servo driver, and an action instruction is sent to the servo driver by means of digital communication; information sent to the servo driver by the controller for the injection molding machine includes pressure control signals, flow control signals and servo driver responding speed control signals; the control system is provided with a plurality of pressure sensors, one end of each pressure sensor is connected with a needed detection point, and the other end of each pressure sensor is connected with the controller for the injection molding machine, thereby forming a signal feedback system with the plurality of pressure sensors; and the pressure sensors and the rotational speed sensor are directly connected with the controller for the injection molding machine to realize automatic closed-loop regulation on pressure and flow.
Description
Technical field
The utility model relates to a kind of injection machine field, relates in particular to a kind of control system of injection machine.
Background technology
Prior art is carried out the analog quantity communication between controller of plastic injection molding and the servo-driver shown in accompanying drawing 1, by pressure, the flow indication of controller of plastic injection molding to the action of servo-driver distribution of machine.Servo-driver is controlled the injection machine servomotor according to the computing of pressure sensor feedback signal.According to the indication that controller of plastic injection molding provides, servo-driver can only provide a fixing response speed.
But there is following shortcoming in prior art:
(1) controller of plastic injection molding is controlled to servo-drive transmission analog signals, because the unstable of analog signals perhaps is interfered easily, so cause the instability of injection machine operation easily, repeatable accuracy is poor.
(2) information sent to servo-driver of controller of plastic injection molding has only two kinds: pressure controling signal and flow control signal; Because not to the control signal of actuator response speed; So in whole injection machine operation control all is to move according to identical actuator response speed; The needed pressure of the everything of injection machine, flow all go to carry out according to this response speed like this.But each moves needed response speed and inequality; So just produced a problem, if that is: response speed is transferred soon, so when the action operation that does not need response fast; Just be easy to generate the vibrations of hydraulic shock and motor, cause service life of a machine to be affected; If response speed is transferred slow, the action that can cause the requirement ask for something to respond fast again can not be accomplished good effect, has reduced the performance of machine, has also wasted the highly-responsive of servo-drive system.
(3) prior art is because pressure sensor signal feeds back to servo-driver, and servo-driver can only receive a pressure sensor signal.So the formed closed-loop control of control system belongs to local closed-loop control, and can not the more high-precision a plurality of pressure sensor signal feedback processing systems of extension realization, the raising of injection machine performance retrained.
Summary of the invention
The purpose of the utility model is in order to solve the existing technical problem of aforementioned injection machine, and the application provides a kind of new control system for shot machine and control method.
The utility model is to realize above-mentioned purpose through following technical scheme:
A kind of control system for shot machine comprises controller of plastic injection molding, servo-driver, servomotor; To hydraulic system the quantitative oil pump of pressure is provided, pressure sensor, speed probe, wherein controller of plastic injection molding links to each other with servo-driver; Send action command to servo-driver, servo-driver links to each other with servomotor, the control motor rotation, and motor links to each other with oil pump; In order to drive the oil pump running, pressure sensor is installed on the oil circuit that needs to detect, and speed probe is installed in the servomotor; Described controller of plastic injection molding comprises: the pressure control module, be used for pressure controlling value according to the work at present stage, and when the force value of the pressure sensor that collects and pressure controlling value have difference, the output valve of regulating pressure signal; Flow-control module is used for the flow-control value according to the work at present stage, when the rotating speed corresponding flow value of the speed probe that collects and flow-control value have difference, and the output valve of regulating flow signal; Said servo-driver comprises: the torque drive unit is used for converting pressure signal into the moment of torsion control signal; The rotating speed driver element is used for converting flow signal to tach signal; It is characterized in that: set up the digital communication agreement between (1) controller of plastic injection molding and the servo-driver, adopt the digital communication mode to send action command to servo-driver; (2) information sent to servo-driver of controller of plastic injection molding has pressure controling signal, flow control signal and servo-driver response speed control signal; (3) at least two pressure sensors, an end of each pressure sensor links to each other with required test point, and the other end directly links to each other with controller of plastic injection molding, forms a plurality of pressure sensor signal feedback system; (4) pressure sensor is realized pressure, the adjusting of flow automated closed-loop with direct being connected with controller of plastic injection molding of speed probe.
Further, said at least two pressure sensors, the pressure when one of them is used to detect injection, the pressure when detecting the folding mould.
Further, described private clothes motor is the private clothes of permanent-magnet synchronous motors.Particularly; The private clothes of described permanent-magnet synchronous motor is connected with the direct axle of oil pump; Oil pump adopts gear pump, and the private clothes of permanent-magnet synchronous motor shaft adopts internal spline, and gear pump shaft adopts external splines; Described spline adopts that the displacement number of teeth is 0.8, pressure angle is 20 ° involute spline, and inside and outside spline directly connects.
Again further, described motor is not selected servomotor for use, and selects stepper motor for use.
A kind of method of utilizing aforementioned said control system for shot machine control injection machine injection and folding mould; Comprise: controller of plastic injection molding is according to action of injection processing parameter setting value; Through with the digital communication agreement of servo-driver, send action command to servo-driver, i.e. flow, pressure and response instruction fast; Servo-driver is commanded the rotating speed of servomotor according to the flow instruction of receiving; Limit the torque of servomotor according to pressure instruction,, realize the height response of action of injection, high performance characteristics according to the quick response instruction of action of injection needs; Corresponding hydraulic fluid flow rate and pressure are exported in the running of driven by servomotor oil pump, enter in the injection cylinder; Promote injection mechanism and accomplish action of injection; In this course, a pressure sensor feeds back to controller of plastic injection molding with actual oily force value, the instruction that controller of plastic injection molding sends to servo-driver according to the instant computing correction of numerical value of feedback; To guarantee that actual act and demand for control are consistent, and have formed the injection closed-loop system;
When carrying out the action of folding mould; Controller of plastic injection molding is according to folding mould action processing parameter setting value, through with the digital communication agreement of servo-driver, send action command to servo-driver; Be flow, pressure and medium speed's response instruction; Servo-driver is commanded the rotating speed of servomotor according to the flow instruction received, limits the torque of servomotor according to pressure instruction, according to medium speed's response instruction of folding mould action needs; Realize that the folding mould moves medium response speed, stress the characteristics of stationarity; The running of driven by servomotor oil pump; Export corresponding hydraulic fluid flow rate and pressure, enter in the folding mould oil cylinder, promote clasp mould mechanism and accomplish the action of folding mould; In this course; Another pressure sensor feeds back to controller of plastic injection molding with the force value of actual oil, and the instruction that controller of plastic injection molding sends to servo-driver according to the instant computing correction of numerical value of feedback is consistent to guarantee actual act and demand for control.Realized and a different independent folding mould closed-loop system of injection closed-loop control.
The utility model realizes that the servo-controlled mode of digital substep is different fully with prior art, is mainly reflected in:
(1) communication modes.Traditional technology is to send the voltage and current analog signals by controller of plastic injection molding to servo-driver, and driver is carried out action according to this signal; In the utility model, what communication was adopted is to send digital quantity signal by controller of plastic injection molding to servo-driver through communications protocol, and driver is carried out action according to data signal, has improved execution accuracy of action and stability.
(2) increased the response speed control data.Technology in the past, the information that controller of plastic injection molding sends to servo-driver have only two kinds: pressure controling signal and flow control signal; In the utility model; Controller of plastic injection molding not only has pressure controling signal and flow control signal to the information that servo-driver sends; Also increased servo-driver response speed control signal; When injection machine was done different action, servo-driver can require according to the response speed that controller of plastic injection molding provides or action response carries out the control to servomotor, had realized dividing action that the purpose of respective response speed regulation is provided to each.This makes ability of the servo high response of injection machine give full play to, and the complete machine performance effectively improves, move more steady, effect such as raising such as complex optimum such as prolongations in service life grade.
Response speed control can adopt known frequency converter to realize.Further, the present invention provides wherein a kind of concrete frequency converter connected mode.Be that controller of plastic injection molding control system links to each other with frequency converter, frequency converter links to each other with servo-driver (frequency converter also can be built in the servo-driver and directly link to each other with motor), and servo-driver comes drive motors work.Motor is not quite identical in the running frequency pace of change of different process section; Also be that the operation response speed that the different process section requires is different; Controller of plastic injection molding is according to different response speed requirements; (frequency converter can calculate correspondent frequency control signal value and motor shifts to an earlier date the speed change time point according to input control signal to output response speed control signal; Also can control signal be converted into the frequency control signal value in advance and motor shifts to an earlier date the speed change time point, send frequency converter then to and control by controller of plastic injection molding) to the frequency converter that links to each other with servo-driver, control the running of motor to the operation response speed control signal of servo-driver transmission motor through frequency converter; Realize different speed response requirement, reach purpose energy-conservation or the prolongation service life of equipment.
(3) pressure closed loop feeds back signal to controller of plastic injection molding.Traditional technology is, the closed loop feedback signal of pressure sensor is given servo-driver, and servo-driver carries out calculation process according to this signal, and the motion of adjustment motor belongs to the local closed-loop control of executive component; In the utility model; The closed loop feedback signal of pressure sensor is given controller of plastic injection molding, carries out computing relatively through controller of plastic injection molding, and the result is offered servo-driver; Realize the whole closed-loop control of injection machine, better accomplished the control of injection machine overall operation.
(4) a plurality of pressure signal acquisition processing systems have been increased.In the technology in the past; The signal of pressure sensor sends to servo-driver; So servo-driver can only receive handle a pressure signal control system can not the more high-precision a plurality of pressure sensor signal feedback processing systems of extension realization, retrained the raising of injection machine performance.In the utility model, can the signal of a plurality of pressure sensors be sent to controller of plastic injection molding, controller of plastic injection molding can carry out calculation process according to each pressure sensor signal, reaches the accurate control to each pressure detecting point.Adopt the method for this patent, can increase substantially the servo-controlled precision of injection machine, and the basic controlling system is provided for multi-functional expansion.
Description of drawings:
Fig. 1: the injection machine hierarchy of control sketch map of prior art;
Fig. 2: the described injection machine hierarchy of control of the utility model sketch map.
Description of reference numerals:
The 1-controller of plastic injection molding, 2-servo-driver, 3-servomotor, 4-oil pump, 5-pressure sensor (survey injection pressure), 6-pressure sensor (surveying the folding molding pressure), 7-speed probe.
The specific embodiment
Below in conjunction with concrete embodiment the utility model has been done further description.
Injection machine is by man-machine interface--and-controller of plastic injection molding carries out the commands for controlling of everything.Injection machine action control procedure is basic identical, by injection, folding mould, eject, plastify, the seat advance and retreat have formed everything, wherein main action is for injecting and the folding mould, these two actions have the greatest impact to machine performance.
Of Fig. 2, a kind of control system for shot machine comprises controller of plastic injection molding 1, servo-driver 2; Servomotor 3 provides the quantitative oil pump 4 of pressure, pressure sensor (5,6) to hydraulic system; Speed probe 7, wherein controller of plastic injection molding 1 links to each other with servo-driver 2, sends action command to servo-driver 2, and servo-driver 2 links to each other with servomotor 3; 3 runnings of control motor, motor 3 links to each other with oil pump 4, in order to drive oil pump 4 runnings; Pressure sensor (5,6) is installed on the oil circuit that needs to detect, and speed probe 7 is installed in the servomotor 3; Described controller of plastic injection molding 1 comprises: the pressure control module, be used for pressure controlling value according to the work at present stage, and when the force value of the pressure sensor that collects and pressure controlling value have difference, the output valve of regulating pressure signal; Flow-control module is used for the flow-control value according to the work at present stage, when the rotating speed corresponding flow value of the speed probe that collects and flow-control value have difference, and the output valve of regulating flow signal; Said servo-driver comprises: the torque drive unit is used for converting pressure signal into the moment of torsion control signal; The rotating speed driver element is used for converting flow signal to tach signal; It is characterized in that: set up the digital communication agreement 1. between (1) controller of plastic injection molding 1 and the servo-driver 2, adopt the digital communication mode to send action command to servo-driver; (2) controller of plastic injection molding not only has pressure controling signal and flow control signal to the information that servo-driver sends, and has also increased servo-driver response speed control signal 3.; (3) a plurality of pressure sensors (5,6), an end of each pressure sensor links to each other with required test point, and the other end directly links to each other with controller of plastic injection molding 1, forms a plurality of pressure sensor signal feedback system; (4) pressure sensor (5,6) is realized pressure, the adjusting of flow automated closed-loop with 7 direct being connected with controller of plastic injection molding 1 of speed probe.
Further, 4. 2. said a plurality of pressure sensors (5,6), the pressure when wherein having one to be used to detect injection also have the pressure when detecting the folding mould.
Further, described private clothes motor is the private clothes of permanent-magnet synchronous motors.Particularly; The private clothes of described permanent-magnet synchronous motor is connected with the direct axle of oil pump; Oil pump adopts gear pump, and the private clothes of permanent-magnet synchronous motor shaft adopts internal spline, and gear pump shaft adopts external splines; Described spline adopts that the displacement number of teeth is 0.8, pressure angle is 20 ° involute spline, and inside and outside spline directly connects.What connect like this is better, more steady.Above-mentioned axle connects and also can adopt other forms of spline to connect to be connected with gear etc.
Again further, described motor is not selected servomotor for use, and selects stepper motor for use.
The operating process of concrete injection and folding mould is: controller of plastic injection molding 1 is according to action of injection processing parameter setting value; Through with 1. agreement of the digital communication of servo-driver 2; Send action command to servo-driver 2; Be voltage (flow), electric current (pressure) and fast response instruction 3., servo-driver 2 is commanded the rotating speed of servomotor 3 according to the voltage of receiving (flow), instructs the torque that limits servomotor 3 according to electric current (pressure); According to the quick response instruction of action of injection needs, realize the height response of action of injection, high performance characteristics.Servomotor 3 drives oil pump 4 runnings; Export corresponding hydraulic fluid flow rate and pressure, enter in the injection cylinder, promote injection mechanism and accomplish action of injection; In this course; 2. pressure sensor 5 feeds back to controller of plastic injection molding 1 with the force value of actual oil, and 5. speed probe 7 feeds back to controller of plastic injection molding with the motor speed value (flow) of reality, the instruction that controller of plastic injection molding 1 sends to servo-driver 2 according to the instant computing correction of numerical value of feedback; To guarantee that actual act and demand for control are consistent, and have formed the injection closed-loop system.
When carrying out the action of folding mould; Controller of plastic injection molding 1 is according to folding mould action processing parameter setting value, through with 1. agreement of the digital communication of servo-driver, send action command to servo-driver 2; Be voltage (flow), electric current (pressure) and medium speed's response instruction 3.; The voltage (flow) that servo-driver 2 bases are received is commanded the rotating speed of servomotor, and instruction limits the torque of servomotor 3 according to electric current (pressure), according to medium speed's response instruction of folding mould action needs; Realize that the folding mould moves medium response speed, stress the characteristics of stationarity.Servomotor 3 drives oil pump 4 runnings; Export corresponding hydraulic fluid flow rate and pressure; Enter in the folding mould oil cylinder, promote clasp mould mechanism and accomplish the action of folding mould, in this course; 4. pressure sensor 6 feeds back to controller of plastic injection molding 1 with the force value of actual oil; 5. speed probe 7 feeds back to controller of plastic injection molding 1 with the motor speed value of reality, and the instruction that controller of plastic injection molding 1 sends to servo-driver 2 according to the instant computing correction of numerical value of feedback is consistent to guarantee actual act and demand for control.Realized and a different independent folding mould closed-loop system of injection closed-loop control.
Carry out the control 3. of friction speed response instruction through difference is moved,, effectively improve performance, stationarity and the control accuracy of machine in conjunction with attainable closed-loop system.
The maximum bright spot of the utility model is:
(1) servo-driver is adjusted the action control rate according to the response speed control signal, optimizes the overall operation of injection machine.
(2) reduce the interference of communication, improved data transmission credibility.
(3) realize the whole closed loop of injection machine, improved the precision of motion control.
(4) a plurality of pressure signal acquisition process have further improved the running precision of injector.Certainly; The above only is a kind of embodiment of the utility model; Should be understood that those skilled in the art; Under the prerequisite that does not break away from the utility model principle, can also make some improvement and retouching, these improvement and retouching all belong within the protection domain of the utility model claim.
Claims (5)
1. a control system for shot machine comprises controller of plastic injection molding, servo-driver, servomotor; To hydraulic system the quantitative oil pump of pressure is provided, pressure sensor, speed probe, wherein controller of plastic injection molding links to each other with servo-driver; Send action command to servo-driver, servo-driver links to each other with servomotor, the control motor rotation, and motor links to each other with oil pump; In order to drive the oil pump running, pressure sensor is installed on the oil circuit that needs to detect, and speed probe is installed in the servomotor; Described controller of plastic injection molding comprises: the pressure control module, be used for pressure controlling value according to the work at present stage, and when the force value of the pressure sensor that collects and pressure controlling value have difference, the output valve of regulating pressure signal; Flow-control module is used for the flow-control value according to the work at present stage, when the rotating speed corresponding flow value of the speed probe that collects and flow-control value have difference, and the output valve of regulating flow signal; Said servo-driver comprises: the torque drive unit is used for converting pressure signal into the moment of torsion control signal; The rotating speed driver element is used for converting flow signal to tach signal; It is characterized in that: set up the digital communication agreement between (1) controller of plastic injection molding and the servo-driver, adopt the digital communication mode to send action command to servo-driver; (2) information sent to servo-driver of controller of plastic injection molding has pressure controling signal, flow control signal and servo-driver response speed control signal; (3) a plurality of pressure sensors, an end of each pressure sensor links to each other with required test point, and the other end directly links to each other with controller of plastic injection molding, forms a plurality of pressure sensor signal feedback system; (4) pressure sensor is realized pressure, the adjusting of flow automated closed-loop with direct being connected with controller of plastic injection molding of speed probe.
2. control system for shot machine as claimed in claim 1 is characterized in that: said a plurality of pressure sensors, the pressure when wherein having one to be used to detect injection also has the pressure when detecting the folding mould.
3. control system for shot machine as claimed in claim 1 is characterized in that: described servomotor is a permanent magnet synchronous servo motor.
4. control system for shot machine as claimed in claim 1 is characterized in that: described motor is not selected servomotor for use, selects stepper motor for use.
5. control system for shot machine as claimed in claim 3; It is characterized in that: described permanent magnet synchronous servo motor is connected with the direct axle of oil pump; Oil pump adopts gear pump, and the permanent magnet synchronous servo motor axle adopts internal spline, and gear pump shaft adopts external splines; Described spline adopts that the displacement number of teeth is 0.8, pressure angle is 20 ° involute spline, and inside and outside spline directly connects.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2012201228153U CN202528404U (en) | 2012-03-29 | 2012-03-29 | Control system for injection molding machine |
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| CN2012201228153U CN202528404U (en) | 2012-03-29 | 2012-03-29 | Control system for injection molding machine |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102626979A (en) * | 2012-03-29 | 2012-08-08 | 宁波恩瑞德机电科技有限公司 | Control system of injection molding machine |
| CN104960170A (en) * | 2015-05-29 | 2015-10-07 | 张东海 | Intelligent injection molding machine and injection molding method thereof |
| CN108843550A (en) * | 2018-07-10 | 2018-11-20 | 赵东昕 | A kind of Intelligent servo grouting pump |
| US10518454B2 (en) | 2016-03-04 | 2019-12-31 | Delta Electronics, Inc. | Control system and method of injection molding machine |
| CN113246422A (en) * | 2021-04-09 | 2021-08-13 | 杭州电子科技大学 | Pressure flow decoupling control method for permanent magnet synchronous motor hydraulic system for injection molding machine |
-
2012
- 2012-03-29 CN CN2012201228153U patent/CN202528404U/en not_active Expired - Fee Related
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102626979A (en) * | 2012-03-29 | 2012-08-08 | 宁波恩瑞德机电科技有限公司 | Control system of injection molding machine |
| CN104960170A (en) * | 2015-05-29 | 2015-10-07 | 张东海 | Intelligent injection molding machine and injection molding method thereof |
| US10518454B2 (en) | 2016-03-04 | 2019-12-31 | Delta Electronics, Inc. | Control system and method of injection molding machine |
| US11059211B2 (en) | 2016-03-04 | 2021-07-13 | Delta Electronics, Inc. | Injection molding control method |
| CN108843550A (en) * | 2018-07-10 | 2018-11-20 | 赵东昕 | A kind of Intelligent servo grouting pump |
| CN113246422A (en) * | 2021-04-09 | 2021-08-13 | 杭州电子科技大学 | Pressure flow decoupling control method for permanent magnet synchronous motor hydraulic system for injection molding machine |
| CN113246422B (en) * | 2021-04-09 | 2021-12-21 | 杭州电子科技大学 | Pressure flow decoupling control method for permanent magnet synchronous motor hydraulic system for injection molding machine |
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| Date | Code | Title | Description |
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| C14 | Grant of patent or utility model | ||
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| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20121114 Termination date: 20130329 |