CN107877781B - Injection (mo(u)lding) machine - Google Patents

Abstract

The present invention provides a kind of injection (mo(u)lding) machine, it is suppressed that the Under Thermal Fatigue Damage of current circuit.Injection (mo(u)lding) machine of the invention includes three-phase alternating current motor, drives movable part；And control device, electric current is supplied to the three-phase alternating current motor according to the difference of the actual value of physical quantity to be controlled and setting value, the control device supplies electric current to the three-phase alternating current motor according to the balance of the size of the current instantaneous value in the actual value of the physical quantity and the difference of setting value and each phase of the three-phase alternating current motor.

Description

Injection (mo(u)lding) machine

This application claims the priority based on Japanese patent application the 2016-195067th filed on September 30th, 2016. Its full content applied is applied in this specification by reference.

Technical field

The present invention relates to a kind of injection (mo(u)lding) machines.

Background technique

There is the electrodynamic type injection device recorded in patent document 1 injection screw and driving injection screw to carry out forward-reverse Electric servomotor.The electrodynamic type injection device has control device, which successively carries out following each process: vector product The resin for being stored in the front of injection screw applies the injection fillers process of injection pressure；To above-mentioned product after the injection fillers process The resin deposited applies the defined pressure maintaining process for keeping pressure；And it is assigned to above-mentioned injection screw corresponding to the plasticating condition of resin Back pressure back pressure process.In the control device, since at the end of above-mentioned pressure maintaining process to above-mentioned back pressure process when until connect Continue and the torque limit values of above-mentioned electric servomotor are set as to the torque limit values of above-mentioned back pressure process start time or more, and from Above-mentioned electric servomotor is set as zero-speed state until at the end of above-mentioned back pressure process at the end of above-mentioned pressure maintaining process.

Patent document 1: Japanese Unexamined Patent Publication 6-285926 bulletin

Injection (mo(u)lding) machine includes three-phase alternating current motor, drives movable part；And control device, according to physical quantity to be controlled Actual value and setting value difference to three-phase alternating current motor supply electric current.As three-phase alternating current motor, such as use three-phase synchronous Motor.

The state of three-phase alternating current motor is remained the state of low speed, high output by control device in pressure maintaining process etc..This When, electric current persistently concentrates on specific one phase in three phases sometimes.

In particular, identical movement is repeated in order to manufacture identical molded product repeatedly in injection (mo(u)lding) machine, therefore movable Portion stops at identical position every time, and electric current is easy to concentrate on specific one phase.

In the past, Under Thermal Fatigue Damage occurred because of the current circuit overload of specific one phase sometimes.

Summary of the invention

The present invention is completed in view of the above subject, and main purpose is to provide a kind of heat for inhibiting current circuit The injection (mo(u)lding) machine of fatigue rupture.

In order to solve the above problems, a mode according to the present invention, provides following injection (mo(u)lding) machine, includes

Three-phase alternating current motor drives movable part；And

Control device is supplied according to the difference of the actual value of physical quantity to be controlled and setting value to the three-phase alternating current motor Electric current,

The control device is each according to the actual value of the physical quantity and the difference of setting value and the three-phase alternating current motor The balance of the size of current instantaneous value in phase supplies electric current to the three-phase alternating current motor.

Invention effect

A mode according to the present invention provides a kind of injection (mo(u)lding) machine of Under Thermal Fatigue Damage for inhibiting current circuit.

Detailed description of the invention

Fig. 1 is the figure of the state at the end of the die sinking of the injection (mo(u)lding) machine of one embodiment of expression.

Fig. 2 is the figure of state when indicating the molding of the injection (mo(u)lding) machine of an embodiment.

Fig. 3 is the control device for indicating an embodiment and the figure of the three-phase alternating current motor controlled by control device.

Fig. 4 is the flow chart for indicating an example of the processing in the pressure maintaining process based on control device.

Fig. 5 is the figure of an example for indicating that the speed of injection motor and the pressure of electric current and moulding material change over time.

Fig. 6 is another for indicating the speed of injection motor and the pressure of electric current and moulding material and changing over time Figure.

Symbol description

10- mold closing mechanism, 20- toggle mechanism, 21- crosshead, 25- mold motor, 40- injection device, 43- screw rod, 46- Motor, 50- liftout attachment are injected, 51- ejects motor, 53- knock-pin, 60- injection device mobile device, the shifting of 61- injection device Dynamic motor, 90- control device, 95- power supplier unit, 99- signal generation portion.

Specific embodiment

Hereinafter, being illustrated with reference to attached drawing to mode for carrying out the present invention, to identical or corresponding knot in each attached drawing Structure marks identical or corresponding symbol and omits the description.

Fig. 1 is the figure of the state at the end of the die sinking of the injection (mo(u)lding) machine of one embodiment of expression.Fig. 2 is to indicate that one implements The figure of state when the molding of the injection (mo(u)lding) machine of mode.As shown in Figures 1 and 2, injection (mo(u)lding) machine has frame Fr, molding dress Set 10, injection device 40, liftout attachment 50, injection device mobile device 60 and control device 90.

Firstly, being illustrated to mold closing mechanism 10 and liftout attachment 50.In the explanation of mold closing mechanism 10 and liftout attachment 50, The moving direction (Fig. 1 and Fig. 2 in right direction) of movable pressure plate 13 when by die closing is used as front, by the movable pressure plate 13 when being opened Moving direction (Fig. 1 and Fig. 2 in left direction) be illustrated as rear.

Mold closing mechanism 10 carries out the die closing of die device 30, molding, die sinking.Mold closing mechanism 10 is for example, horizontal, mould opening and closing Direction is horizontal direction.Mold closing mechanism 10 has fixation clip 12, movable pressure plate 13, toggle seat 15, connecting rod 16, toggle mechanism 20, motor 25 and movement conversion mechanism 26 are molded.

Fixation clip 12 is fixed on frame Fr.Cover half is installed in the face opposed with movable pressure plate 13 of fixation clip 12 32。

Movable pressure plate 13 is set as moving freely along the guiding piece (such as guide rail) 17 being layed on frame Fr, and is set as It is free to advance or retreat relative to fixation clip 12.Dynamic model 33 is installed on the face opposed with fixation clip 12 of movable pressure plate 13.

By making movable pressure plate 13 retreat relative to fixation clip 12, to carry out die closing, molding, die sinking.By cover half 32 Die device 30 is constituted with dynamic model 33.

Toggle seat 15 and fixation clip 12 link across interval, and are placed in a manner of moving freely along mould opening and closing direction On frame Fr.In addition, toggle seat 15 can also be moved freely along the guiding piece being layed on frame Fr.The guidance of toggle seat 15 Part can also be general with the guiding piece 17 of movable pressure plate 13.

In addition, fixation clip 12 is fixed on frame Fr in present embodiment, toggle seat 15 is opened and closed relative to frame Fr along mould Direction, which is moved freely, is fixed on frame Fr but it is also possible to be toggle seat 15, and fixation clip 12 is relative to frame Fr along mould opening and closing side To moving freely.

Connecting rod 16 is across interval connection fixation clip 12 and toggle seat 15.Connecting rod 16 can be used more.Each connection Bar 16 is parallel with mould opening and closing direction, and is extended according to mold clamping force.Molding force detector is provided at least 1 connecting rod 16 18.Molding force detector 18 detects mold clamping force by detecting the strain of connecting rod 16, and the signal for indicating testing result is sent out It send to control device 90.

In addition, molding force detector 18 is not limited to strain gage type, it is also possible to piezoelectric type, condenser type, fluid pressure type, electricity Magnetic-type etc., and its installation site is also not limited to connecting rod 16.

Toggle mechanism 20 is disposed between movable pressure plate 13 and toggle seat 15.Toggle mechanism 20 is by crosshead 21, Yi Duilian Bar group etc. is constituted.Each connection rod set has the 1st connecting rod 22 and the 2nd connecting rod 23 elastically linked by pin etc..1st connecting rod 22 Swing is installed into freely by pin etc. relative to movable pressure plate 13, the 2nd connecting rod 23 is pacified relative to toggle seat 15 by pin etc. Dress up swing freely.2nd connecting rod 23 is installed on crosshead 21 via the 3rd connecting rod 24.If making crosshead 21 retreat, the 1st connecting rod 22 And the 2nd connecting rod 23 then stretch, movable pressure plate 13 relative to toggle seat 15 retreat.

In addition, the structure of toggle mechanism 20 is not limited to Fig. 1 and structure shown in Fig. 2.Such as in Fig. 1 and Fig. 2, respectively connect The quantity of the node of bar group is 5 but it is also possible to be 4, and an end of the 3rd connecting rod 24 can connect with the 1st connecting rod 22 and the 2nd The node of bar 23 combines.

Molding motor 25 is installed on toggle seat 15, and runs toggle mechanism 20.Molding motor 25 makes crosshead 21 retreat, To keep the 1st connecting rod 22 and the 2nd connecting rod 23 flexible, and movable pressure plate 13 is made to retreat.Molding motor 25 is directly linked to movement and turns It changes planes structure 26, but movement conversion mechanism 26 can also be linked to via conveyer belt or belt wheel etc..

The rotary motion for molding motor 25 is converted to the linear motion of crosshead 21 by movement conversion mechanism 26.Movement conversion Mechanism 26 includes lead screw shaft and the feed screw nut screwed togather with lead screw shaft.Ball or roller can also be made between lead screw shaft and feed screw nut Between.

Mold closing mechanism 10 carries out die closing process, molding process, die sinking process etc. under the control of control device 90.

In die closing process, driving molding motor 25 makes crosshead 21 advance to die closing end position with setting speed, thus So that movable pressure plate 13 is advanced, and contacts dynamic model 33 with cover half 32.The position of crosshead 21 or speed are for example using molding motor 25 encoder 25a etc. is detected.The rotation of encoder 25a detection molding motor 25, and the signal that will indicate the testing result It is sent to control device 90.

It molds in process, by further driving molding motor 25 to be advanced further crosshead 21 from die closing end position To die-closed position, to generate mold clamping force.Cavity space 34, injection device 40 are formed when molding between dynamic model 33 and cover half 32 To the moulding material of 34 filling liquid of cavity space.The mold material cures of filling, to can get molded product.Cavity space 34 Quantity can be multiple, multiple molded products can be obtained simultaneously at this time.

It is opened in process, retreats crosshead 21 to die sinking end position with setting speed by driving molding motor 25, To make movable pressure plate 13 retreat, and make dynamic model 33 far from cover half 32.Later, liftout attachment 50 ejects molded product from dynamic model 33.

In addition, the mold closing mechanism 10 of present embodiment has molding motor 25 as driving source, but it also can replace molding Motor 25 has hydraulic cylinder.Also, mold closing mechanism 10 can be used as the mould opening and closing linear motor of apparatus, electric with having as molding Magnet.

Liftout attachment 50 ejects molded product from die device 30.Liftout attachment 50 has ejection motor 51, movement interpreter Structure 52 and knock-pin 53.

Ejection motor 51 is installed on movable pressure plate 13.Ejection motor 51 is directly linked to movement conversion mechanism 52, but can also To be linked to movement conversion mechanism 52 via conveyer belt or belt wheel etc..

The rotary motion for ejecting motor 51 is converted to the linear motion of knock-pin 53 by movement conversion mechanism 52.Movement conversion Mechanism 52 includes lead screw shaft and the feed screw nut screwed togather with lead screw shaft.Ball or roller can also be made between lead screw shaft and feed screw nut Between.

Knock-pin 53 is free to advance or retreat in the through hole of movable pressure plate 13.The front end of knock-pin 53 be movably arranged Movable member 35 in the inside of dynamic model 33 contacts.The front end of knock-pin 53 can link with movable member 35, can also not Connection.

Liftout attachment 50 carries out ejection process under the control of control device 90.

It ejects in process, so that knock-pin 53 is advanced with setting speed by driving ejection motor 51, to make movable member 35 advance, and eject molded product.Later, driving ejection motor 51 retreats knock-pin 53 with setting speed, and makes movable member 35 retreat to original position.The position of knock-pin 53 or speed are for example detected using the encoder 51a of ejection motor 51.It compiles The rotation of code device 51a detection ejection motor 51, and the signal for indicating the testing result is sent to control device 90.

Then, injection device 40 and injection device mobile device 60 are illustrated.Injection device 40 and injection device move In the explanation of dynamic device 60, illustrate difference with mold closing mechanism 10 etc., by moving direction (Fig. 1 and Fig. 2 of the screw rod 43 when filling Middle left direction) it is used as front, the moving direction of the screw rod 43 when measuring (Fig. 1 and Fig. 2 in right direction) is said as rear It is bright.

Injection device 40 is set to the glide base Sb free to advance or retreat relative to frame Fr, and relative to die device 30 into It moves back freely.Injection device 40 is contacted with die device 30, and the 34 filling molding material of cavity space into die device 30.It is logical The moulding material cooling and solidifying for making to be filled in cavity space 34 is crossed, to can get molded product.Injection device 40 is for example with cylinder Body 41, nozzle 42, screw rod 43, cooler 44, measure motor 45, injection motor 46, pressure detector 47, heater 48 and temperature Detector 49.

Cylinder body 41 heats the moulding material supplied from supply mouth 41a to inside.Supply mouth 41a is formed in cylinder body 41 Rear portion.The periphery at the rear portion of cylinder body 41 is provided with the coolers such as water cooling cylinder 44.The front of cooler 44, in the periphery of cylinder body 41 It is provided with the heaters such as band heater 48 and temperature detector 49.

Cylinder body 41 divides into multiple regions along the axial direction (Fig. 1 and Fig. 2 in left and right directions) of cylinder body 41.Each region is equipped with heating Device 48 and temperature detector 49.Control device 90, which controls heater 48, makes the detection temperature of temperature detector 49 in each region As set temperature.

Nozzle 42 is set to the front end of cylinder body 41, and presses on die device 30.The periphery of nozzle 42 is provided with heating Device 48 and temperature detector 49.Control device 90, which controls heater 48, makes the detection temperature of nozzle 42 become set temperature.

Screw rod 43 is to rotate freely and mode free to advance or retreat is disposed in cylinder body 41.If rotating screw rod 43, form Material is sent to front along the spiral helicine slot of screw rod 43.Moulding material is sent to front on one side, on one side by coming from cylinder body 41 Heat and gradually melt.As the moulding material of liquid is sent to the front of screw rod 43 and is accumulated in the front of cylinder body 41, screw rod 43 retreat.Later, if screw rod 43 is made to advance, the moulding material in 43 front of screw rod is projected from nozzle 42, and is filled into mold dress It sets in 30.

Measure motor 45 rotates screw rod 43.

Injection motor 46 makes screw rod 43 retreat.The rotary motion for injecting motor 46 passes through the movement conversion mechanisms such as ball-screw It is converted into the linear motion of screw rod 43.

Pressure detector 47 is set to the strength transmission path between injection motor 46 and screw rod 43, and detects and act on pressure The load of force detector 47.The signal for indicating the testing result is sent to control device 90 by pressure detector 47.Pressure detecting The testing result of device 47 be used to control or monitor the pressure that screw rod 43 bears from moulding material, for the back pressure of screw rod 43, from spiral shell Bar 43 acts on the pressure etc. of moulding material.

Injection device 40 is filled process, pressure maintaining process, measurement process etc. under the control of control device 90.

In filling work procedure, driving injection motor 46 makes screw rod 43 advance with setting speed, and will accumulate before screw rod 43 The moulding material of the liquid of side is filled to the cavity space 34 in die device 30.The position of screw rod 43 or speed are for example using note The encoder 46a of motor 46 is penetrated to detect.The rotation of encoder 46a detection injection motor 46, and will indicate the testing result Signal is sent to control device 90.If the position of screw rod 43 reaches setting position, pressure maintaining process (institute is switched to from filling work procedure Call V/P switching).The setting speed of screw rod 43 can be changed according to the position of screw rod 43 or time etc..

After the position arrival setting position of screw rod 43 in filling work procedure, temporarily cease screw rod 43 In the setting position, V/P switching is carried out later.Screw rod 43 can also not be set to stop, replacing makes spiral shell before V/P switching 43 dead slow ahead of bar or dead slow astern.

In pressure maintaining process, driving injection motor 46 pushes screw rod 43 to set pressure forwards, thus to die device 30 Interior moulding material applies pressure.So as to supplement the insufficient moulding material because of cooling meat.The pressure example of moulding material Such as detected using pressure detector 47.The signal for indicating the testing result is sent to control device 90 by pressure detector 47.

In pressure maintaining process, the moulding material of cavity space 34 is gradually cooled, cavity space 34 at the end of pressure maintaining process The moulding material that entrance is cured is blocked.The state, which is referred to as, feeds dot encapsulation, to prevent the forming material from cavity space 34 Material adverse current.After pressure maintaining process, process is begun to cool.In cooling process, the solidification of the moulding material in cavity space 34 is carried out. In order to shorten molding cycle, measurement process can also be carried out in cooling process.

In measurement process, driving measure motor 45 rotates screw rod 43 with setting speed, and along the helical form of screw rod 43 Slot moulding material is sent to front.As it does so, moulding material gradually melts.As the moulding material of liquid is sent to screw rod 43 Front and the front for being accumulated in cylinder body 41, screw rod 43 are retreated.The revolving speed of screw rod 43 is for example using the coding of measure motor 45 Device 45a is detected.The signal for indicating the testing result is sent to control device 90 by encoder 45a.

It in measurement process, is sharply retreated to limit screw rod 43, injection motor 46 can also be driven and screw rod 43 is applied Set back pressure.The back pressure applied for screw rod 43 is for example detected using pressure detector 47.Pressure detector 47 will indicate should The signal of testing result is sent to control device 90.If screw rod 43 is retreated to setting position, and is accumulated and advised in the front of screw rod 43 Quantitative moulding material, then terminate measurement process.

In addition, the injection device 40 of present embodiment is coaxial approach screw but it is also possible to be preformed mode.Preformed mode Injection device the moulding material melted in plasticizing cylinder is supplied into injection cylinder, and injected from injection cylinder into die device Moulding material.Screw rod is rotated freely or is rotated freely and is movably disposed in plasticizing cylinder, and plunger is movably matched Set in injection cylinder.

Injection device mobile device 60 has makes injection device 40 relative to die device under the control of control device 90 The mobile motor 61 of 30 mobile injection devices.The rotary motion of the mobile motor 61 of injection device passes through the movements such as ball-screw conversion Mechanism and the linear motion for being converted into injection device 40.

In addition, the injection device mobile device 60 of present embodiment is electrodynamic type but it is also possible to be fluid pressure type.

Injection device mobile device 60 in filling work procedure or pressure maintaining process to 30 pressing nozzle 42 of die device, to press down Moulding material processed leaks between die device 30 and nozzle 42.It will be known as nozzle to the process of 30 pressing nozzle 42 of die device Contact operation will be known as nozzle touch force to the pressing force of 30 pressing nozzle 42 of die device.

Injection device mobile device 60 in order to protect die device 30 and mold closing mechanism 10, can after pressure maintaining process and Nozzle touch force is reduced before next filling work procedure or is separated from die device 30 by nozzle 42.

In addition, injection device mobile device 60 can be right before the circular flow for manufacturing identical molded product repeatedly starts 30 pressing nozzle 42 of die device, and reduce after circular flow terminates nozzle touch force or from die device 30 by nozzle 42 Separation.

As shown in Figure 1 or 2, control device 90 has CPU (Central Processing Unit, central processing list Member) 91, storage mediums 92, input interface 93 and the output interface 94 such as memory.Control device 90 is stored in CPU91 execution Program in storage media 92, to carry out various controls.Also, control device 90 is received using input interface 93 from outside Signal sends signal to outside by output interface 94.

Fig. 3 is the control device for indicating an embodiment and the figure of the three-phase alternating current motor controlled by control device.Make Molding motor 25 or injection motor 46, ejection motor 51, the mobile motor 61 of injection device can be enumerated for three-phase alternating current motor 110 Deng.

Control device 90 has the power supplier unit 95 for example supplied electric power from power supply 100 to three-phase alternating current motor 110. Power supplier unit 95 have for example by the AC power supplied from power supply 100 be converted to direct current power converter 96, from turn Parallel operation 96 is supplied to the DC connector 97 of direct current power, the direct current power supplied from DC connector 97 is carried out electrical power conversion and is supplied To the inverter 98 to three-phase alternating current motor 110.

Inverter 98 has 3 bridge arms being for example made of 2 switch elements.In addition, the number of bridge arm is not particularly limited. As the concrete example of switch element, such as MOSFET (Metal Oxide Semiconductor Filed-Effect can be enumerated Transistor, metal oxide semiconductor field effect tube), IGBT (Insulated Gate Bipolar Transistor, Insulated gate electrode transistor npn npn), bipolar junction transistor etc..Diode inverse parallel is connected to each switch element.Diode can be built-in In each switch element.

Control device 90 also has the signal generation portion 99 of the signal for the switch element for for example generating control inverter 98.Letter Number generating unit 99 is for example according to physical quantity to be controlled (hereinafter, also known as " control amount ".) actual value and setting value difference into Row such as PID (Proportional, Integration and Differential, ratio, integral and differential) operation etc. Operation, and current-order is found out in such a way that above-mentioned difference becomes zero, and be compared with carrier wave to current-order, to generate PWM (Pulse Width Modulation, pulse width modulation) signal.Inverter 98 is according to from signal generation portion 99 Pwm signal is switched, and supplies alternating current to three-phase alternating current motor 110.

In addition, the number of three-phase alternating current motor 110 is 1 but it is also possible to be multiple in Fig. 3.Corresponding multiple three-phase alternating current horses Up to the 110 multiple inverters 98 of setting.Multiple inverters 98 can be connected in parallel in a converter 96, be also possible to a conversion Device 96 supplies direct current power to multiple inverters 98.Alternatively, it is also possible to the multiple inverters 98 of correspondence, multiple converters 96 are set.

Control device 90 controls injection motor 46 for example to control pressure maintaining process.In pressure maintaining process, control amount is forming material The pressure of material, actual value Pa are detected by pressure detector 47, and setting value Pref is pre-stored within storage medium 92.Control Device 90 controls injection motor 46 in such a way that the difference of actual value Pa and setting value Pref become zero.

The state for injecting motor 46 is remained the state of low speed, high output by control device 90 in pressure maintaining process.At this Under state, current instantaneous value Iu, Iv, Iw of each phase of supply to injection motor 46 become substantially certain, it is possible to making High current persistently concentrates on any phase.Here, Iu indicates that the current instantaneous value of U phase, Iv indicate the current instantaneous value of V phase, The current instantaneous value of Iw expression W phase.

Therefore, control device 90 is in pressure maintaining process according to the electric current wink of the difference of actual value Pa and setting value Pref and each phase The size of duration | Iu |, | Iv |, | Iw | balance to injection motor 46 supply electric current.Thereby, it is possible to avoid high current from persistently collecting In any phase in three phases the case where.

Fig. 4 is the flow chart for indicating an example of the processing in the pressure maintaining process based on control device.Processing shown in Fig. 4 exists V/P starts when switching.After V/P switching, control device 90 becomes zero side immediately with the difference of actual value Pa and setting value Pref Formula supplies electric current to injection motor 46.

In step S11 shown in Fig. 4, control device 90 confirms the size of the difference of actual value Pa and setting value Pref | Pref- Pa | it whether is threshold value Pth or less.Threshold value Pth first passes through test etc. in advance and finds out, and is stored in storage medium 92.Threshold value Pth is for example Defect rate according to molded product etc. and set.

| Pref-Pa | when more than Pth (step S11, "No"), the pressure of moulding material exceeds permissible range, therefore controls Device 90 returns to step S11, and continues the later processing of step S11.

On the other hand, | Pref-Pa | when being Pth or less (step S11, "Yes"), the pressure of moulding material is in permissible range It is interior, and the state for being speculated as injection motor 46 becomes the state of low speed, high output, therefore control device 90 enters step S12. Confirm in the processing after step S12 | Iu |, | Iv |, | Iw | balance, detailed content will be aftermentioned.

In addition, control device 90 can actually confirm whether the state of injection motor 46 is low speed, is high defeated in step S11 State out.The speed of injection motor 46 can be detected by encoder 46a etc..Also, the output of motor 46 is injected with torque Detected value, torque instruction, current detection value, current-order etc. indicate.The speed for injecting motor 46 is threshold value Vth or less and injects When the output of motor 46 is threshold value Tth or more, the state for being judged to injecting motor 46 is the state of low speed, high output.These thresholds Value Vth, Tth is found out for example, by the Under Thermal Fatigue Damage test or thermal-stress analysis etc. of current circuit.

It is assumed that high current will not continue to concentrate when the state for being confirmed as injection motor 46 is not low speed, the high state exported Any phase in three-phase, hardly happens the Under Thermal Fatigue Damage of current circuit.Therefore, control device 90 can be without at this time Step S12 later processing, and can not confirming | Iu |, | Iv |, | Iw | balance.At this point, control device 90 can be down to pressure maintaining Electric current is supplied to injection motor 46 according to the difference of actual value Pa and setting value Pref as usual until the end of process.On the other hand, When the state for being confirmed as injection motor 46 is low speed, the high state exported, control device 90 enters step S12.

In step S12, control device 90 confirms | Iu | it whether is Ith or less.Ith is threshold value, if | Iu | be Ith hereinafter, Then it is set as making remaining | Iv | with | Iw | it is roughly equal.

The electric angle of the electric angle of U phase, the electric angle of V phase and W phase respectively differs 120 °.Therefore, the current instantaneous value of any phase Size closer to zero, then the size of the current instantaneous value of remaining two-phase is closer to identical value.

| Iu | when more than Ith (step S12, "No"), electric current is possible to not be scattered in V phase with W phase and high current persistently collects In any phase in three phases, therefore control device 90 enters step S13.In step S13, control device 90 confirms | Iv | be No is Ith or less.| Iv | when more than Ith (step S13, "No"), electric current is possible to not be scattered in W phase with U phase and high current is held The continuous any phase concentrated in three-phase, therefore control device 90 enters step S14.In step S14, control device 90 confirms | Iw | It whether is Ith or less.| Iw | when more than Ith (step S14, "No"), electric current is possible to not to be scattered in U phase and V phase and high current Any phase in three-phase is persistently concentrated on, therefore control device 90 enters step S15.

In step S15, control device 90 is by | Iu |, | Iv |, | Iw | any of become Ith it is below in a manner of rotate note Penetrate the electric angle of each phase of motor 46.Thereby, it is possible to by current dissipation to remaining two-phase.

The electric angle for injecting each phase of motor 46 is found out according to current-order etc..Inject the electric angle rotation of each phase of motor 46 During 60 °, | Iu |, | Iv |, | Iw | any of become Ith or less.In addition, control device 90 can will inject motor 46 The electric angle of each phase rotate 60 ° or more.

The rotation amount for injecting the electric angle of each phase of motor 46 is set to actual value Pa and the difference of setting value Pref falls into appearance Perhaps the degree in range.The number of pole-pairs for injecting motor 46 is usually 2 or more, therefore the rotation amount of mechanical angle is the rotation amount of electric angle Less than half.The rotation amount very little of mechanical angle compared with the rotation amount of electric angle, therefore the screw rod 43 generated by the rotation of electric angle Shift in position very little.The variation very little of actual value Pa as a result, and the difference of actual value Pa and setting value Pref can be made to fall into appearance Perhaps in range.

Fig. 5 is the figure of an example for indicating that the speed of injection motor and the pressure of electric current and moulding material change over time. In Fig. 5, in moment t1, the state for injecting motor 46 becomes the state of low speed, high output, | Iu |, | Iv |, | Iw | it is all larger than Ith, And high current concentrates on V phase.

Therefore, as shown in figure 5, control device 90 rotates the electric angle of each phase from moment t1 to moment t2, will | Iw | it is set as Ith Below.Current dissipation is in V phase and U phase as a result, therefore can be avoided high current and persistently concentrate on V phase.

In Fig. 5, from moment t1 to moment t2, the direction to the driving force for reducing injection motor 46 is, retreats screw rod 43 Direction rotary injection motor 46 each phase electric angle.Moment t2's | Iu |, | Iv |, | Iw | maximum value less than moment t1 | Iu |, | Iv |, | Iw | maximum value.

Fig. 6 is another for indicating the speed of injection motor and the pressure of electric current and moulding material and changing over time Figure.In Fig. 6, in moment t1, the state for injecting motor 46 becomes the state of low speed, high output, | Iu |, | Iv |, | Iw | it is all larger than Ith, and high current concentrates on V phase.

Therefore, as shown in fig. 6, control device 90 is from moment t1 to the electric angle of each phase of moment t2 rotary injection motor 46, Will | Iu | it is set as Ith or less.Current dissipation is in V phase and W phase as a result, therefore can be avoided high current and persistently concentrate on V phase.

In Fig. 6, from moment t1 to moment t2, the direction to the driving force for increasing injection motor 46 is, screw rod 43 is made to advance Direction rotary injection motor 46 each phase electric angle.Moment t2's | Iu |, | Iv |, | Iw | maximum value less than moment t1 | Iu |, | Iv |, | Iw | maximum value.

After step S15, the electricity of each phase of fixed injection motor 46 until can terminating down to pressure maintaining process of control device 90 Angle returns to step S11 to continue the position of holding screw rod 43 in Fig. 4, continue the later processing of step S11.It returns To step S11, so as to confirm the difference of actual value Pa and setting value Pref whether in permissible range after the step s 15.

On the other hand, | Iu | when being Ith or less (step S12, "Yes"), | Iv | when being Ith or less (step S13, "Yes") Or | Iw | when being Ith or less (step S14, "Yes"), current uniform is dissipated in arbitrary two-phase.Therefore it is able to suppress current circuit Under Thermal Fatigue Damage, thus control device 90 enters step S16.

In step S16, control device 90 fixes the electric angle of each phase of injection motor 46 to keep the position of screw rod 43.This When, control device 90 can replace the pressure of moulding material as control amount and use the position of screw rod 43.That is, control device 90 It can replace pressure control and carry out position control.

After step S16, the electricity of each phase of fixed injection motor 46 until can terminating down to pressure maintaining process of control device 90 Angle, but S17 is entered step in Fig. 4.Step S17 later processing is for coping with the change for passing through caused actual value Pa by the time Dynamic processing.The variation of actual value Pa is generated such as due to because gradually solidifying the moulding material in die device 30.By temperature It is effective when the volume change of moulding material caused by changing is larger or when the quality of molded product is easy dependent on actual value Pa.

In step S17, control device 90 confirms | Pref-Pa | whether it is greater than Pth.The threshold value Pth used in step S17 It is identical value in Fig. 4 but it is also possible to be different values from the threshold value Pth used in step S11.

| Pref-Pa | when being greater than Pth (step S17, "Yes"), the pressure oscillation of moulding material is larger, therefore control device 90 enter step S18.In step S18, control device 90 can release the fixation of the electric angle of each phase of injection motor 46, can also be with Release position control.Control device 90 can replace position control and carry out pressure control.Specifically, control device 90 is with reality The difference of actual value Pa and setting value Pref supply electric current to injection motor 46 as zero mode.Later, control device 90 returns to Step S11, and continue the later processing of step S11.

On the other hand, | Pref-Pa | when being Pth or less (step S17, "No"), the pressure of moulding material, which maintains, allows In range, therefore control device 90 enters step S19.In step S19, control device 90 confirms that the termination condition of pressure maintaining process is It is no to have set up.The termination condition of pressure maintaining process is, for example, to switch elapsed time from V/P to reach the stipulated time.

Continue when pressure maintaining process (step S19, "No"), control device 90 returns to step S16, and continues to walk Rapid S16 later processing.

On the other hand, terminate when pressure maintaining process (step S19, "Yes"), control device 90 terminates this time to handle.

In addition, setting value Pref is constant until end since pressure maintaining process in present embodiment, but can according to from Pressure maintaining process has started elapsed time and has been switched.If setting value Pref is switched, control device 90 returns to step S11, and carry out the later processing of step S11.

As described above, control device 90 is in pressure maintaining process according to the difference of actual value Pa and setting value Pref and injection horse Up to the size of the current instantaneous value in 46 each phase | Iu |, | Iv |, | Iw | balance to injection motor 46 supply electric current.As a result, It can be avoided any phase that high current persistently concentrates in three-phase.

Control device 90 can be with the difference of actual value Pa and setting value Pref in permissible range and the electric current wink of any phase The size of duration becomes threshold value Ith mode below and supplies electric current to injection motor 46.Thereby, it is possible to by current dissipation to residue Two-phase.

Control device 90 is to judge any phase in the case where the difference of actual value Pa and setting value Pref are in permissible range The size of current instantaneous value whether be threshold value Ith or less.As long as the size of the current instantaneous value of any phase be threshold value Ith with Under, then current dissipation can be judged as in remaining two-phase.

In addition, control device 90 may be the case where whether direct confirmation electric current is scattered in any two-phase, and judge Whether the size of the current instantaneous value of the size of the current instantaneous value of any phase and remaining any phase is threshold value or less.For example, step In rapid S12, can replace | Iu | whether be Ith judgement below and carry out | Iv | and | Iw | difference whether be that threshold value is below sentence It is disconnected.Also, in step S13, can replace | Iv | whether be Ith it is below judgement and carry out | Iw | and | Iu | difference whether be threshold It is worth judgement below.In addition, can replace in step S14 | Iw | whether be Ith judgement below and carry out | Iu | with | Iv | it Whether difference is threshold value judgement below.The judgement of the variation can directly confirm whether electric current is scattered in the feelings of any two-phase Condition, in contrast, judgement shown in Fig. 4 can be carried out simply.

Control device 90 is, when being judged as each in the case where the difference of actual value Pa and setting value Pref are in permissible range The size of the current instantaneous value of phase | Iu |, | Iv |, | Iw | when being more than threshold value Ith, the electric angle of each phase of rotary injection motor 46. The rotation amount of electric angle for injecting each phase of motor 46 is set to | Iu |, | Iv |, | Iw | any of become Ith or less.By This, can make current dissipation in remaining two-phase.

The electric angle for injecting each phase of motor 46 is found out according to current-order etc..Inject the electric angle rotation of each phase of motor 46 During 60 °, | Iu |, | Iv |, | Iw | any of become Ith or less.In addition, control device 90 can will inject motor 46 The electric angle of each phase rotate 60 ° or more.

The rotation amount of the electric angle of each phase of injection motor 46 can be set to actual value Pa and the difference of setting value Pref is fallen Enter the degree in permissible range.In addition, injection motor 46 each phase electric angle rotation amount can be set to actual value Pa with The difference of setting value Pref exceeds permissible range.At this point, control device 90 carries out the control of following (1)~(3), in order to avoid the electricity of each phase The electric angle of each phase returns to original angle after the rotation of angle.

(1) control device 90 uses the position of screw rod 43 as control amount to replace the pressure of moulding material.That is, control dress Setting 90 replaces pressure to control and carry out position control.Specifically, control device 90 keeps the position of screw rod 43.Therefore, it injects The electric angle of each phase of motor 46 is fixed to postrotational electric angle.

(2) control device 90 can continue the pressure using moulding material as control amount, and can be to according to actual value The current-order that the difference of Pa and setting value Pref are formulated is corrected, so that the electric angle of each phase is fixed to postrotational electric angle.

(3) control device 90 can continue the pressure using moulding material as control amount, and can by actual value Pa with The permissible range of the difference of setting value Pref changes wider, and falls into the difference in the permissible range after changing, thus by each phase Electric angle be fixed as postrotational electric angle.But difference do not fall within change after permissible range in when, control device 90 can be again The electric angle of each phase is rotated, so that difference is fallen into the permissible range after change.

Electric angle is fixed in the fixed situation of electric angle and step S16 after the step s 15 for the control of above-mentioned (1)~(3) In the case where can also apply.When the control of above-mentioned (3) carries out in step s 16, the threshold value Pth of step S17 can be set For the threshold value Pth greater than step S11.

In this specification, " electric angle is fixed " not only comprising electric angle completely without variation and completely fixed situation, also include The case where electric angle slightly changes in error range.

The direction of the electric angle of each phase of rotary injection motor 46 can be the direction for reducing the driving force of injection motor 46, I.e., the direction for retreating screw rod 43 is also possible to increase the direction of the driving force of injection motor 46, i.e., screw rod 43 is made to advance Direction.If by the electric angle of each phase of rotary injection motor 46 so that | Iu |, | Iv |, | Iw | maximum value become smaller.

The direction of the electric angle of each phase of rotary injection motor 46 can be | Iu |, | Iv |, | Iw | any of for the first time at The lesser direction of the rotation amount of electric angle until for Ith or less.If the rotation amount of electric angle is minimum, therefore actual value Pa It changes minimum.

The control of the electric angle of each phase as rotary injection motor 46, such as the control of following (1)~(3) can be enumerated.

(1) control device 90 uses the position of screw rod 43 as control amount to replace the pressure of moulding material.That is, control dress Setting 90 replaces pressure to control and carry out position control.Specifically, control device 90 corrects the position of screw rod 43 with rotary injection The electric angle of each phase of motor 46.

In addition, the control amount as position control, can use electric angle or the mechanical angle of injection motor 46 to replace screw rod 43 position.

(2) control device 90 uses the speed of screw rod 43 as control amount to replace the pressure of moulding material.That is, control dress Setting 90 replaces pressure to control and carry out speed control.Specifically, control device 90 corrects the speed of screw rod 43 to correct screw rod 43 position is with the electric angle of each phase of rotary injection motor 46.

(3) control device 90 can continue the pressure using moulding material as control amount, and to according to actual value Pa with The current-order that the difference of setting value Pref is formulated is corrected, so that the electric angle of each phase rotates.

On the other hand, control device 90 is, when the situation in the difference of actual value Pa and setting value Pref in permissible range Under be judged as injection motor 46 in any phase current instantaneous value size be threshold value Ith or less when, can fix injection horse Up to the electric angle of 46 each phase.As long as any phase current instantaneous value size be Ith hereinafter, as long as electric current be scattered in it is remaining Two-phase.

Control device 90 is to judge actual value Pa and setting value in the case where the electric angle of each phase of fixed injection motor 46 Whether the difference of Pref is in permissible range.Thereby, it is possible to cope with the variation of the actual value Pa generated with time going by.It is practical The variation of value Pa is generated such as due to because gradually solidifying the moulding material in die device 30.It is being formed as caused by temperature change It is effective when the volume change of material is larger or when the quality of molded product is easy dependent on actual value Pa.

In addition, as shown in figure 4, when control device 90 carries out the difference of actual value Pa and setting value Pref in permissible range (step S11, "Yes"), whether the size for injecting the current instantaneous value of any phase in motor 46 is threshold value Ith judgement below (step S12~S14), but the present invention is not limited to this.

In current instantaneous value Iu, Iv, Iw of three-phase, if maximum value is labeled as Imid, minimum labeled as Imax, median Value is labeled as Imin, then the summation of Imax, Imid, Imin are usually zero.That is, the formula of Imax+Imid+Imin=0 is set up.

Therefore, it can replace progress (A) | Iu |, | Iv |, | Iw | whether it is respectively threshold value Ith judgement below and only carries out (B) size of median Imid | Imid | it whether is threshold value Ith judgement below.

Also, | Imid |=| Imax+Imin | formula set up, therefore can carry out (C) | Imax+Imin | whether be threshold value Ith judgement below.Therefore, | Imax+Imin | indicate the size of the sum of Imax and Imin.

The judgement of above-mentioned (A), (B), (C) are essentially identical judgement, as long as carrying out any one judgement, be equivalent into Other 2 judgements are gone.

In addition, working as | Imid | when=0 formula is set up, then | Imax |=| Imin | formula become vertical.Therefore, it is possible to judge that | Imax | and | Imin | the size of difference whether be threshold value or less.Here, | Imax | indicate the size of Imax, | Imin | it indicates The size of Imin.

Control device 90 can find out the difference of actual value Pa and setting value Pref in permissible range and in injection motor 46 Any phase current instantaneous value size become threshold value Ith screw rod 43 below position.It the position can be according to past The prediction such as actual conditions.Injection (mo(u)lding) machine, therefore being capable of root in order to manufacture identical molded product repeatedly and identical movement repeatedly It is predicted according to past actual conditions etc..That is, control device 90 can have learning functionality.At this point, control device 90 can be with After pressure maintaining process starts, screw rod 43 is set to be moved to the position found out in advance, and screw rod 43 is kept in the position.

Also, control device 90 can without injection motor 46 in any phase current instantaneous value size whether be Threshold value Ith judgement (step S12~S14) below, replaces, carries out other judgements.For example, control device 90 may determine that Whether the electric angle of each phase can be rotated, so that the difference of actual value Pa and setting value Pref maintain in permissible range and reduce | Iu |, | Iv |, | Iw | maximum value.The judgement is for example according to by the variation of the rotation amount of electric angle or direction of rotation and actual value Pa It measures and establishes the corresponding and past data of storage and carry out.If control device 90, which is judged as, can make actual value Pa and setting value The difference of Pref maintains in permissible range and reduces | Iu |, | Iv |, | Iw | maximum value, then execute the rotation of the electric angle.It should The rotation of electric angle can not be sentenced by whether the size of the current instantaneous value of any phase in injection motor 46 is that threshold value Ith is below The influence of disconnected result and carry out.

Also, control device 90 can be according to past material feeding | Iu |, | Iv |, | Iw | balance determine this material feeding | Iu |, | Iv |, | Iw | balance.In 1 material feeding, die closing process, molding process, filling work procedure, pressure maintaining process, bosher are carried out Sequence, die sinking process etc..Here, past material feeding can be 1 time nearest material feeding, it is also possible to nearest multiple material feeding.For example, Control device 90 can be such that actual value Pa and the difference of setting value Pref maintains in permissible range in the pressure maintaining process of each material feeding And the size of the current instantaneous value in each material feeding is become the smallest phase to change by the sequence of U phase, V phase, W phase.Electric current The size of instantaneous value becomes maximum phase and is not fixed, therefore can further suppress Under Thermal Fatigue Damage.In addition, sequence is not special It limits, such as can be the sequence of U phase, W phase, V phase.Also, the change that the size of current instantaneous value becomes the smallest phase can be with It carries out, can also be carried out 1 time in every multiple material feeding in material feeding each time.In addition, the size of current instantaneous value becomes minimum Phase can between the two-phase in three-phase alternate selection.Also, the size of current instantaneous value becomes the smallest phase can be random Selection, without selecting in order.

More than, the embodiment etc. of injection (mo(u)lding) machine is illustrated, but the present invention is not limited to above-mentioned embodiment party Formula etc. is able to carry out various modifications and improvement in the main scope of the invention recorded in technical solution.

Control device 90, can basis when making the state of three-phase alternating current motor 110 remain low speed, the high state exported The balance of the actual value of control amount and the difference of setting value and the size of the current instantaneous value in each phase of three-phase alternating current motor 110 to Three-phase alternating current motor 110 supplies electric current.The type of three-phase alternating current motor 110 and the movable part driven by three-phase alternating current motor 110 Type be not particularly limited.

Control device 90 reduces the feelings that the speed of screw rod 43 temporarily ceases screw rod 43 etc. before switching V/P Under condition, the state for injecting motor 46 is remained to the state of low speed, high output.Therefore, V/P is being switched it by control device 90 It, can be according to the actual value of control amount and the difference of setting value and injection motor 46 in the case where the preceding speed for reducing regulation screw rod 43 Each phase in current instantaneous value size balance to injection motor 46 supply electric current.At this point, movable part is, for example, screw rod 43, Control amount is position or the speed of screw rod 43.In addition, movable part is plunger when injection device is preformed mode.

The state for molding motor 25 is remained the state of low speed, high output by control device 90 in molding process.Therefore, Control device 90 can be according in the actual value of control amount and the difference of setting value and each phase of molding motor 25 in molding process Current instantaneous value size balance to molding motor 25 supply electric current.At this point, movable part is, for example, crosshead 21, control amount For the position of crosshead 21.In addition, movable part can be movable pressure plate 13, control amount can be the position of movable pressure plate 13.And And control amount can be mold clamping force.

But it is the horizontal but it is also possible to be opening of horizontal direction that mold closing mechanism 10 is die opening and closing direction in fig. 1 and 2 Die closing direction is the vertical of up and down direction.Vertical mold closing mechanism has lower platen, top board, toggle seat, toggle mechanism and connection Bar etc..Any of lower platen and top board are used as fixation clip, another is used as movable pressure plate.It is installed in lower platen There is lower die, upper mold is installed in top board.Die device is constituted by lower die and upper mold.Lower die can be installed on pushing via turntable Plate.Toggle seat is disposed in the lower section of lower platen.Toggle mechanism is disposed between toggle seat and lower platen.Connecting rod and vertical direction In parallel and run through lower platen, and links top board and toggle seat.

When top board is movable pressure plate and lower platen is fixation clip, die sinking process is carried out and increase top board. After die sinking process terminates, toggle mechanism is in the state of overlapping, therefore toggle multiplying power is smaller, control device 90 to die closing process Until beginning, the state for molding motor is made to remain the state of low speed, high output.Therefore, control device 90 is in die sinking process knot It, can be according in the actual value of control amount and the difference of setting value and each phase of molding motor after beam and before die closing process starts Current instantaneous value size balance to molding motor supply electric current.At this point, movable part is, for example, crosshead 21, control amount is The position of crosshead 21.In addition, movable part can be movable pressure plate, control amount can be the position of movable pressure plate.

Control device 90 makes the state of the mobile motor 61 of injection device remain low speed, the high shape exported when nozzle contacts State.Therefore, control device 90 can be moved when nozzle is contacted according to the actual value of control amount and the difference of setting value and injection device The balance of the size of current instantaneous value in each phase of dynamic motor 61 supplies electric current to the mobile motor 61 of injection device.At this point, can Dynamic portion is, for example, injection device 40, and control amount is position or the nozzle touch force of injection device 40.

The state for ejecting motor 51 is remained the state of low speed, high output by control device 90 sometimes in ejection process. As such case, such as molded product can be enumerated and be close to die device 30, and the feelings that the clinging force interferes knock-pin 53 to advance Condition.Therefore, control device 90 can be according to the actual value of control amount and the difference of setting value and ejection motor 51 in ejection process Each phase in current instantaneous value size balance to ejection motor 51 supply electric current.At this point, movable part is, for example, knock-pin 53, control amount is position or the speed of knock-pin 53.

Liftout attachment 50 can and be the compression set of the moulding material of the cavity space in compression mould device 30.This When, the simultaneous compression motor for compression set of ejection motor 51.In addition, compression set can be provided separately with liftout attachment 50.

Compression set has the compression motor for keeping the compression-type core being disposed in die device 30 mobile.Compression motor and pressure The movement converter section that the rotary motion of compression motor is converted to the linear motion of compression-type core can be set between miniature core.

Control device 90 makes to compress horse in the compression section of the moulding material of the cavity space in compression mould device 30 The state reached remains the state of low speed, high output.Therefore, control device 90 can be according to the reality of control amount in compression section The balance of the size of current instantaneous value in each phase of the difference and compression motor of actual value and setting value supplies electric current to compression motor. At this point, movable part is, for example, compression-type core, control amount is position or the speed of compression-type core.

Claims (10)

1. a kind of injection (mo(u)lding) machine, includes

Three-phase alternating current motor drives movable part；And

Control device supplies electricity to the three-phase alternating current motor according to the difference of the actual value of physical quantity to be controlled and setting value Stream,

The control device is according in the actual value of the physical quantity and the difference of setting value and each phase of the three-phase alternating current motor Current instantaneous value size balance to the three-phase alternating current motor supply electric current,

The physical quantity is pressure, mold clamping force, the position of movable part, the speed of movable part and the nozzle contact of moulding material At least one of power.

2. injection (mo(u)lding) machine according to claim 1, wherein

The control device is with the difference of the actual value of the physical quantity and setting value in permissible range and the three-phase alternating current horse The size of the current instantaneous value of any phase in reaching becomes threshold value mode below and supplies electric current to the three-phase alternating current motor.

3. injection (mo(u)lding) machine according to claim 1 or 2, wherein

The control device is to judge institute in the case where the difference of the actual value of the physical quantity and setting value is in permissible range Whether the size for stating the current instantaneous value of any phase in three-phase alternating current motor is threshold value or less.

4. injection (mo(u)lding) machine according to claim 1 or 2, wherein

The control device is to judge when in the case where the difference of the actual value of the physical quantity and setting value is in permissible range When being more than threshold value for the size of the current instantaneous value of each phase of the three-phase alternating current motor, the three-phase alternating current motor is rotated The electric angle of each phase.

5. injection (mo(u)lding) machine according to claim 1 or 2, wherein

The control device is to judge when in the case where the difference of the actual value of the physical quantity and setting value is in permissible range When size for the current instantaneous value of any phase in the three-phase alternating current motor is threshold value or less, the fixed three-phase alternating current horse The electric angle of each phase reached.

6. injection (mo(u)lding) machine according to claim 1 or 2, wherein

The control device is to judge the physical quantity in the case where electric angle of each phase of the fixation three-phase alternating current motor Whether the difference of actual value and setting value is in permissible range.

7. injection (mo(u)lding) machine according to claim 1 or 2, wherein

The control device finds out the actual value of the physical quantity and the difference of setting value in permissible range and the three-phase alternating current The size of the current instantaneous value of any phase in motor becomes the position of the threshold value movable part below.

8. injection (mo(u)lding) machine according to claim 1 or 2, wherein

The control device judges whether that the electric angle of each phase of the three-phase alternating current motor can be rotated so that the physical quantity The difference of actual value and setting value maintains in permissible range and reduces the current instantaneous value of each phase of the three-phase alternating current motor Size maximum value.

9. injection (mo(u)lding) machine according to claim 1 or 2, wherein

The control device determines the balance of this material feeding according to the balance of past material feeding.

10. injection (mo(u)lding) machine according to claim 1 or 2, wherein

The control device is with the difference of the actual value of the physical quantity and setting value in permissible range and the three-phase alternating current horse The size of the current instantaneous value of any phase reached and the current instantaneous value of any phase of residue in the three-phase alternating current motor The difference of size becomes threshold value mode below and supplies electric current to the three-phase alternating current motor.