JP3255728B2 - Feedback control method for injection molding machine and injection molding machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a feedback control method for an injection molding machine and an injection molding machine , and more particularly to an injection stroke (a stroke composed of a primary injection stroke and a pressure-holding stroke). The present invention relates to a speed / pressure feedback control technique during an injection retraction stroke by an injection drive source (a screw retraction drive stroke by an injection drive source such as a screw removal operation).

[0002]

2. Description of the Related Art In an injection molding machine, control conditions for injection speed and injection pressure are important factors in molding a good product. Injection molding machines in which the injection speed and injection pressure are feedback-controlled are known. Various proposals have been made.

In a conventional injection molding machine that performs feedback control, generally, in a primary injection step of injecting and filling a molten resin into a cavity of a mold, an actual measured speed approaches a set speed value. The injection pressure feedback control (feedback control giving priority to the injection speed) is performed on the injection pressure, and the injection pressure is fed back so that the measured pressure value approaches the set pressure value in the pressure-holding process in which the pressure-holding pressure is applied to the resin in the mold. Control (feedback control giving priority to injection pressure) is performed.

FIGS. 5A and 5B schematically show the state of the conventional feedback control. FIG. 5A shows the state during the primary injection stroke, and FIG. 5B shows the state during the pressure-holding stroke. Are respectively shown. For example, the feedback control unit 50 in the microcomputer controls the speed setting value Vo and the pressure setting value Po given in advance, and the speed measurement value Vm and the pressure measurement value obtained by appropriately converting the measurement data of the sensor in the injection mechanism 51. During the primary injection stroke, feedback control is performed so that the actual speed value Vm is equal to the set speed value Vo, regardless of the actual pressure value Pm. Regardless of Vm, feedback control is performed so that the measured pressure value Pm matches the set pressure value Po.

[0005] In the case of open control having no feedback function, both the flow rate proportional solenoid valve and the pressure proportional solenoid valve are used during both the primary injection stroke and the pressure-holding stroke to determine the speed or pressure. Although control is performed with priority given to either of them, apparently both speed and pressure are controlled. That is, both the speed setting value and the pressure setting value are set over the entire injection control region, and one of the setting values of the speed and the pressure serves as the upper limit value of the other actual output value.

[0006]

Here, when the primary injection stroke is performed by the speed feedback control as described above, the pressure set value Po is ignored. When the pressure-holding process is performed by the pressure feedback control, the speed setting value Vo is ignored, and during this time, the injection speed control becomes substantially impossible.

However, when the injection process (the primary injection process and the pressure-holding process) is controlled as described above, the resin in the mold approaches the completion of filling at the end of the primary injection process, and the resin in the mold decreases from the resin in the mold. The injection pressure tends to decrease due to the reaction pressure of the injection, but the speed feedback control is performed during the primary injection stroke. Therefore, if the speed set value at the end of the primary injection stroke is high, the set speed will be forced. Therefore, there is a possibility that abnormal load rise may be caused to cause die damage.

In addition, when the pressure filling control is started in a state where the resin filling into the mold is not completely completed (unfilled or insufficiently filled), a predetermined load pressure does not rise. However, feedback control is performed so as to release the pressure to the set pressure value, which may cause an abnormal increase in speed, and may cause damage to the mold and the injection mechanism.

[0009] Therefore, in the condition setting for the conventional feedback control, careful consideration is required. For example, in the primary injection stroke, it is originally desired to set the speed condition with a constant speed setting (one speed setting). Time, which is complicated and requires experience and knowledge, such as the necessity of setting multi-stage speeds in consideration of the influence on pressure, and the time when retry setting is sometimes required many times. It was also a thing to hang. Furthermore, in order to prevent the above-mentioned accidents caused by abnormal pressure rise or speed rise, the machine is urgently stopped in the case of abnormal pressure or speed rise by the function of detecting abnormal pressure / speed separately. Therefore, there is a problem that the machine is often stopped during the continuous molding operation, which is likely to be a factor of reducing the operation efficiency.

Therefore, a technical problem to be solved by the present invention is to solve the above-mentioned problems of the prior art.
The object of the present invention is to provide a feedback control method for an injection molding machine that can suppress occurrence of abnormal pressure rise or abnormal speed rise as much as possible and can easily set conditions for feedback control. Is to do. Another object of the present invention is that, despite feedback control, it can be used in an apparently equivalent manner to the conventional open control, and has the same speed / pressure as the conventional open control. An object of the present invention is to provide a feedback control method in an injection molding machine that can adopt a setting method (can follow a speed / pressure setting method that has been familiar from the past as it is).

[0011]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention measures speed and pressure during operation and compares the measured value with a set value so that the measured value approaches the set value. In addition, for example, in an injection molding machine that performs feedback control of injection speed or feedback control of injection pressure, during speed feedback control of the primary injection stroke,
If the measured pressure exceeds the set pressure,
Switched to force feedback control, and then switched
Measured during pressure feedback control of primary injection stroke
If the measured actual speed exceeds the set speed,
Pressure feedback control, and the pressure
The actual speed measured during feedback control is
If the set value is exceeded, switch to speed feedback control.
The speed feedback of the switched dwelling stroke.
The actual measured pressure value during pressure control exceeds the set pressure value.
Switch to pressure feedback control again
And so on.

[0012]

For example, when the primary injection stroke is executed by the injection speed feedback control, that is, the actual measured value taken in real time is compared with a predetermined speed set value, and the actual measured speed is set to the speed. During feedback control of the injection speed so as to approach the set value, if it is detected that the actual measured pressure value exceeds the allowable pressure value, which is the pressure set value, the feedback control unit determines that the actual measured pressure value is the pressure set value. Is switched to pressure feedback control so as to approach. As a result, the injection pressure is reduced, and the measured pressure value approaches the pressure set value, and as a result, the measured speed value decreases accordingly. Then, when it is detected that the actual measured speed value exceeds the allowable speed value, which is the set speed value, the feedback control unit switches to the injection speed feedback control again. This switching of the feedback control from speed to pressure and pressure to speed is performed during the primary injection stroke.
This is performed regardless of the pressure-holding stroke, so that an abnormal pressure rise during the primary injection stroke is reliably suppressed, and an abnormal speed rise during the pressure-holding stroke is also ensured. Be deterred.

[0013] By doing so, the pressure setting and the speed setting act to control the upper limit of each other, and the occurrence of abnormal pressure rise and abnormal speed rise can be suppressed as much as possible. In addition, the above-mentioned upper limit operation is exactly the same as that in the case of open speed / pressure control. Thus, the safety of speed feedback control → pressure feedback control, pressure feedback control → speed feedback control is very high. Switch automatically,
Moreover, it is sufficient to set exactly the same setting conditions as in the conventional open control in order to perform the same upper limit control action as in the conventional open control, and the setting conditions for the feedback control are easier than in the past.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is an explanatory diagram showing a main configuration of an injection molding machine according to the present embodiment, FIG. 2 is an explanatory diagram schematically showing a feedback control switching method according to the present embodiment, and FIG. 3 is a feedback control according to the present embodiment. It is a graph which shows an example of the relationship between the speed and the pressure of the injection stroke performed by the method.

In FIG. 1, 1 is a heating cylinder, 2 is a screw disposed in the heating cylinder 1 so as to be able to move forward and backward and rotatable, 3 is a hopper for supplying raw materials, and 4 is a rear end of the screw 2 connected thereto. The motor 5 for driving the screw rotation is an injection cylinder (hydraulic cylinder) which is a hydraulic drive source for injection. In the illustrated example, the casing of the motor 4 is fixed to the tip of the piston rod 5a of the injection cylinder 5, and the screw 2 advances together with the motor 4 as the piston rod 5a advances. As is known in the above configuration, the raw material (resin material) supplied from the hopper 3 is transferred to the tip side of the heating cylinder 1 while being kneaded and plasticized by the rotation of the screw 2 driven by the motor 4, and the molten resin is screwed. As the screw 2 is stored at the front end of the screw 2, the screw 2 retreats while controlling the back pressure, and when one shot of molten resin is stored at the front end of the screw 2, the screw rotation is stopped. Then, after a lapse of a predetermined time, when the injection start timing is reached, the screw 2 is driven forward to inject and fill the molten resin into the cavity of the mold (not shown) (primary injection stroke). Enter the pressure-holding process at the pressure-hold switching point,
The holding pressure is continuously applied to the resin in the mold by the forward pressure of the screw 2 for a predetermined time.

In this embodiment, the screw 2 is advanced (injection stroke including a primary injection stroke and a pressure-holding stroke).
The speed (injection speed) or pressure (injection pressure including holding pressure) at the time is feedback-controlled by processing programmed by the microcomputer 20 as described later. That is, in this embodiment,
An electromagnetic control valve (electromagnetic proportional flow control valve also serving as a pressure control valve) 6 is feedback-driven controlled by an electromagnetic control valve driver circuit 9 that receives the output of the microcomputer 20, thereby accumulating the pressure oil from the hydraulic pump 7. (ACC) The feedback control of the flow rate (velocity) of the pressure oil supplied from the (ACC) 8 to the injection cylinder 5 or the feedback control of the pressure of the pressure oil is performed.

Reference numeral 11 denotes a stroke sensor for detecting the forward / backward movement position of the piston rod 5a of the injection cylinder 5, and information detected by the stroke sensor 11 is a microcomputer 20 which will be described later.
Is converted into speed data by the microcomputer 20 with reference to the time measurement information, and is recognized in real time as a measured speed value. Reference numeral 12 denotes a pressure sensor for detecting the oil pressure applied to the injection cylinder 5, and the detection information of the pressure sensor 12 is also sent to a microcomputer 20, which will be described later.
It is converted as needed by 0 and recognized as a measured pressure value in real time.

Reference numeral 20 denotes a microcomputer for controlling the entire injection molding machine, a ROM for storing various I / O interfaces, a main control program and various fixed data, a RAM for reading and writing various flags and measurement data, and a microcomputer for the entire microcomputer. Although it is provided with a CPU (microprocessor) for controlling and executes various processes according to various programs created in advance, in the present embodiment, for convenience of explanation,
The following description will be given assuming that the input processing unit 21, the molding condition setting storage unit 22, the molding process control unit 23, the allowable PV value monitoring unit 24, the feedback control unit 25, the output processing unit 26, and the like are provided. .

The input processing unit 21 receives measurement information from a large number of sensor groups provided in various parts of the machine including the stroke sensor 11 and the pressure sensor 12, and these various measurement information are input to the input processing unit 21. The microcomputer 20 performs appropriate conversion processing according to the information type, and recognizes the information indicating the position, speed, rotation speed, pressure, temperature, and the like in real time by the microcomputer 20, and stores them in an actual measurement value information storage unit (not shown) as necessary. It is captured.

The molding condition setting storage section 22 stores various molding condition values in a rewritable manner. The molding conditions stored in the molding condition setting storage unit 22 include:
For example, control conditions such as a plasticizing process, a mold closing (mold closing) process, an injection process, a cooling process, a mold opening process, an ejecting process, and the like can be given. In the present embodiment, the injection speed condition and the injection pressure condition along the stroke axis from the injection start position to the pressure holding switching point (position) are set as conditions for the primary injection stroke during the injection stroke. I have. As conditions for the pressure-holding stroke during the injection stroke, the injection pressure (pressure-holding pressure) condition along the time axis from the pressure-hold switching time to the pressure-holding end time, and the injection speed (screw advance speed) condition Is set.

Based on a molding process control program created in advance and setting condition values stored in the molding condition setting storage unit 22, the molding process control unit 23 detects a group of sensors provided in each unit of the machine. The molding operation is controlled while referring to the measurement information of the injection cylinder 5 and the time measurement information from the clock means built in the microcomputer 20. Various control signals are output through the output processing unit 26, whereby the injection cylinder 5 is controlled. Control of a large number of driver circuits including an electromagnetic control valve driver circuit 9 for controlling the driving sources of the respective parts of the machine to execute a series of molding steps.

During the injection stroke, the permissible PV value monitoring unit 24 measures the actual measured value V of the speed coming from the input processing unit 21.
m, the actual measured pressure value Pm, and the speed set value Vo and the pressure set value P during the injection stroke stored in the molding condition setting storage unit 22.
o, during the primary injection stroke and the pressure-holding stroke, the magnitude relationship between the measured pressure value Pm and the set pressure value Po is constantly compared, and the magnitude of the measured speed value Vm and the set speed value Vo is constantly compared. Always compare relationships. Then, during the primary injection stroke, the allowable P / V value monitoring unit 24 changes Pm <Pom from the state of Po>
When the transition to Po is detected, the feedback control unit 25 is instructed to switch from the injection speed feedback control to the pressure feedback control, and when the pressure feedback control is performed during the primary injection stroke. Then, when it is detected that Vm> Vo, it is instructed to switch to injection speed feedback control again. On the other hand, the allowable PV value monitoring unit 24
When it is detected that the state has shifted from Vm <Vo to Vm> Vo during the pressure-holding process, the feedback control unit 25
Command to switch from pressure feedback control of injection to speed feedback control, and when speed feedback control is performed during the pressure-holding stroke, P
When it is detected that m> Po, a command is issued to switch to injection pressure feedback control again.

During the injection stroke, the feedback control section 25 measures the actual measured speed Vm,
The actual pressure measured value Pm and the speed set value Vo and the pressure set value Po during the injection stroke stored in the molding condition setting storage unit 22 are fetched, and the speed feedback control or the pressure feedback control is selectively executed. That is, when executing the speed feedback control, the feedback control unit 25 compares the speed setting value Vo and the actual speed measurement value Vm in real time at each position or each time, and compares the speed setting value Vo with the speed. If the actual measured value Vm is deviated, a correction value for matching the actual measured value Vm to the speed set value Vo is calculated, and a speed control signal based on this is generated by, for example, the output processing unit 26, and the electromagnetic control is performed. The output is output to the valve driver circuit 9 and the flow rate, that is, the speed is adjusted and controlled by the electromagnetic control valve 6 as described above. When executing the pressure feedback control, the feedback control unit 25 compares the pressure set value Po and the measured pressure value Pm in real time at each time point or each position, and compares the pressure set value Po with the pressure set value Po. When the measured value Pm is shifted, a correction value for matching the measured pressure value Pm to the set pressure value Po is calculated, and a pressure control signal based on the corrected value is generated by, for example, the output processing unit 26 and the electromagnetic control value is calculated. The pressure is output to the valve driver circuit 9 and the pressure is adjusted and controlled by the electromagnetic control valve 6 as described above.

The above-mentioned feedback control unit 15
In the present embodiment, the arithmetic control processing for feedback control performed in step (1) is based on a so-called PID (proportional / integral / differential) operation. It is assumed that the output is linearly increased / decreased by the integral action with respect to the unit step input in the operation (I), and the time advance is generated by the differential action in the operation (D), and these (P) and (I) , (D) are performed simultaneously to perform feedback control. By performing such PID control, feedback control in anticipation (covering) of hydraulic response can be performed, and overshoot and transmission due to too sharp rise can be suppressed as much as possible, and rise is too slow. , It is possible to eliminate the delay of the arrival time to the target, and to obtain a suitable rising characteristic.

Next, the operation based on the above configuration will be described. When the injection start timing is reached during the continuous molding operation, the primary injection stroke is started by a command of the molding process control unit 23, the injection speed is started to an initial target value, and the allowable PV value is monitored. The unit 24 and the feedback control unit 25 also start operating. That is, the permissible PV value monitoring unit 24 starts taking in the actual measured value Vm and the actual measured pressure value Pm, and starts the processing for comparing the magnitude with the set value as described above. Further, the feedback control unit 25 recognizes that the initial feedback control condition of the primary injection stroke is the injection speed feedback control, and compares the set speed value Vo and the measured actual speed value Vm for each position in real time. Then, the speed feedback control operation is started.

In this primary injection stroke, the allowable P · V
The speed feedback control is performed while the determination result in the value monitoring unit 24 indicates the actual measured pressure value Pm <the pressure set value Po, and if Pm <Po during the primary injection stroke, the primary injection stroke Is always performed by the speed feedback control until the end (up to the pressure holding switching point). But,
During the primary injection stroke, the actual measured pressure value Pm> the set pressure value Po
Is detected by the allowable PV value monitoring unit 24, the allowable PV value monitoring unit 24 sends a feedback command signal to the feedback control unit 25 to switch the injection speed feedback control to the pressure feedback control. Is sent out, and the feedback control unit 25 sets the pressure set value P
o and the measured pressure value Pm are compared in real time for each position, and the pressure feedback control operation is started. Also,
When pressure feedback control is performed during the primary injection stroke, it is allowable that Vm> Vo is satisfied P · V
When the value is detected by the value monitoring unit 24, the allowable PV value monitoring unit 24
Sends a switching command signal to the feedback control unit 25 so as to switch to the injection speed feedback control again, and the control is switched to the speed feedback control.

After reaching the pressure-holding switching point (after the end of the primary injection stroke), the same control is continued. However, when the resin is filled in the mold, the measured pressure value becomes equal to the pressure setting value. Pm> Po, and pressure feedback is obtained. After this state, since the resin is filled in the mold, the actual measured value of the speed does not increase again, and the pressure feedback is continued.

FIG. 2 shows the feedback control unit 2 described above.
5 schematically shows a state of a switching operation between speed feedback control and pressure feedback control according to No. 5; FIG. 3 is a diagram showing an example of the measured speed Vm and the measured pressure Pm during the injection stroke (the primary injection stroke and the pressure-holding stroke).
When the actual measured value Vm> the speed set value Vo in the pressure-holding stroke as shown in FIG. 3A, the speed feedback control is switched to the speed feedback control as shown in FIG. 3B, and when Pm> Po, the pressure feedback control is switched again. Is shown.

According to the present embodiment having such a configuration / operation, it is possible to suppress as much as possible the occurrence of abnormal pressure rise or abnormal speed rise that greatly exceeds the set value (allowable value). Become. In addition, since switching of the speed feedback control with high safety → pressure feedback control, pressure feedback control → speed feedback control is automatically performed, setting conditions for feedback control can be obtained.
This is extremely easy as compared with the condition setting for the conventional feedback control. That is, since the speed setting and the pressure setting act to perform upper limit control on each other to perform the injection control operation, the feedback control for precision molding is performed while the conventional open control that does not perform the feedback control is performed. The upper limit of the speed / pressure can be regulated in the same manner as in the above case, and the same setting method as in the case of the conventional open control can be used. Becomes easy.

In the above-described embodiment, the control during the injection stroke has been described. However, the present invention measures the retraction speed and the retraction pressure during the screw retraction drive stroke (for example, the screw removal stroke) by the injection drive source. However, the present invention can also be applied to the case where feedback control of the retreat speed or feedback control of the retreat pressure is performed so that the measured actual value approaches the set value by comparing the measured actual value with the set value.
That is, in this case, if the measured pressure value measured during the reverse speed feedback control exceeds the pressure set value, the pressure is switched to the pressure feedback control, and the measured speed value measured during the reverse pressure feedback control is the speed. If the set value is exceeded, the control is switched to speed feedback control. By doing so, an abnormal increase in speed or pressure in the screw removal stroke or the like can be avoided.

FIG. 4 is a diagram showing an example of the actually measured speed Vm and the actually measured pressure Pm during the screw retraction drive stroke (screw pulling stroke) by the above-described injection drive source. As shown in the figure, when the entire stroke of screw removal (retraction) is performed by speed feedback control, the actual measured pressure P is affected by the resin adhered to the screw and the like during the retraction.
When m exceeds the allowable pressure value or when the mechanism abuts near the retreat limit, the measured pressure value Pm rises rapidly, and there is a possibility that the screw-related mechanism may be damaged. On the other hand, when the feedback switching control method according to the present invention is employed, as shown in FIG. 4B, for example, as shown in FIG. When the actual measured value Vm> the speed set value Vo during the reverse pressure feedback control, the control is switched again to the speed feedback control. By doing so, it is possible to perform feedback control while preventing abnormal pressure and speed increases even in the screw retraction drive stroke.

Although the present invention has been described with reference to the illustrated embodiments, it is obvious that those skilled in the art can make various modifications without departing from the spirit of the present invention. For example, in the above-described embodiment, feedback control is performed by software processing using a microcomputer, but it is known to those skilled in the art that the equivalent function can be realized by a hardware configuration, that is, an electric circuit using a servo amplifier circuit or the like. It is obvious. Further, in the above-described embodiment, an example in which a hydraulic cylinder (injection cylinder) is used as a drive source for injection has been described. However, an electromagnetic servomotor may be used as a drive source for injection (speed feedback control and output torque control). The present invention can be applied to the case where selection switching is performed with feedback control).

[0033]

As described above, according to the present invention, the upper limit of the speed / pressure is regulated in the same manner as in the conventional open control.
While performing feedback control that is advantageous for precision molding, abnormal pressure rise during speed feedback control and occurrence of abnormal speed rise during pressure feedback control can be suppressed as much as possible. Out,
A feedback control method during an injection stroke in an injection molding machine, which can be easily performed in exactly the same manner as a conventional open control molding machine, can be provided, and its value is enormous.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a main configuration of an injection molding machine according to one embodiment of the present invention.

FIG. 2 is an explanatory diagram schematically showing a state of a feedback control switching method according to one embodiment of the present invention.

FIG. 3 is a graph illustrating an example of a relationship between a speed and a pressure of an injection stroke executed by a feedback control method according to an embodiment of the present invention.

FIG. 4 is a graph illustrating an example of a relationship between a speed and a pressure of a screw removal stroke performed by a feedback control method according to another embodiment of the present invention.

FIG. 5 is an explanatory diagram schematically showing a state of conventional feedback control.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Heating cylinder 2 Screw 5 Injection cylinder 6 Electromagnetic control valve 8 Accumulator 9 Electromagnetic control valve driver circuit 11 Stroke sensor 12 Pressure sensor 20 Microcomputer 21 Input processing unit 22 Molding condition setting storage unit 23 Molding process control unit 24 Permissible PV value monitoring Unit 25 feedback control unit 26 output processing unit

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B29C 45/46-45/57 B29C 45/76-45/82

Claims (4)

(57) [Claims] The injection speed and the injection pressure are measured, and the measured actual value is compared with a set value, and the injection speed feedback control or the injection pressure feedback control is performed so that the actual measured value approaches the set value. In the molding machine, if the measured pressure value during the speed feedback control in the primary injection stroke exceeds the pressure set value, the molding machine is switched to pressure feedback control, and the switched primary
If the speed measurement measured at a pressure feedback control of the injection stroke has exceeded the speed setting value is switched to the speed feedback control again, the pressure of the higher coercive stroke Feed
The actual speed measured during the back control is the speed set value.
If it exceeds, switch to speed feedback control.
In addition, the speed feedback of the switched dwelling stroke
Measured pressure value during control exceeds pressure set value
The pressure feedback control is switched again when the feedback control is performed. 2. A retraction speed and a retraction pressure during a screw retraction drive stroke by an injection drive source are measured, and the measured actual value is compared with a set value to adjust the retreat speed so that the actual measured value approaches the set value. In an injection molding machine that performs feedback control or reverse pressure feedback control, if the actual pressure measured during reverse speed feedback control exceeds the pressure set value, the pressure is switched to pressure feedback control. A feedback control method for an injection molding machine, wherein when a measured speed value during control exceeds a set speed value, the control is switched to speed feedback control. 3. An injection speed and an injection pressure are measured and measured.
The measured value approaches the set value by comparing the measured value with the set value
So that injection speed feedback control or injection pressure
In the injection molding machine that performs the feedback control of the speed, it is measured during the speed feedback control of the primary injection stroke
If the measured pressure exceeds the set pressure, the pressure
Switch to feedback control, and switch the primary
Measured during pressure feedback control during injection stroke
If the actual measured speed exceeds the set speed, the speed
Switch to feedback control to maintain pressure
The actual speed measured during the back control is the speed set value.
If it exceeds, switch to speed feedback control.
In addition, the speed feedback of the switched dwelling stroke
Measured pressure value during control exceeds pressure set value
Switch to pressure feedback control again
Injection means,
Form machine. (4) Screw retraction drive by injection drive source
Measure and measure the retraction speed and retraction pressure during the stroke.
The measured value approaches the set value by comparing the measured value with the set value
Feedback control of reverse speed or reverse pressure
In an injection molding machine that performs feedback control of Pressure measured during reverse speed feedback control
If the measured value exceeds the set pressure, the pressure feedback
Pressure control and reverse pressure feedback
The actual speed measured during control exceeds the speed set value.
Switch to speed feedback control
Injection molding, characterized by having means for controlling
Machine.