JP2016112759A - Control method of injection molding machine, and the injection molding machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To satisfactorily transmit signals from a plurality of sensors to a control device over each step of an injection molding machine by a relatively simple method or a relatively low cost apparatus. In the injection molding machine 11 that transmits closed operation information to the control device 24 and performs closed-loop control of a plurality of processes, the transmission cycle from the sensor 23 that detects operation information mainly used for control in each step to the control device 24 is set. The transmission cycle from the other sensor 33, 39 to the control device 24 is set to be relatively shorter than the transmission cycle from the other sensors 33, 39 to the control device 24. The transmission period from the other sensors 33 and 39 to the control device 24 is made relatively shorter. [Selection] Figure 3

Description

The present invention relates to an injection molding machine control method and an injection molding machine that perform closed loop control of a plurality of processes by transmitting operation information detected by a sensor to a control device.

In the case of an injection molding machine, closed loop control of a plurality of processes is performed by transmitting operation information detected by a sensor to a control device. At that time, the position of various operating parts such as the position of the screw of the injection device in the injection process, the position of the movable platen of the mold clamping device in the mold closing process and the mold opening process, and the position of the ejector pin in the protrusion process are detected by the respective position sensors. Then, the closed loop control of each process is performed by transmitting to the control device and outputting a command signal or the like from the control device to the drive unit of the operating unit. The detection value of the position sensor is displayed on the screen of the injection molding machine, and is stored as molding data in the control device or in a separate storage device.

In the conventional injection molding machine, the transmission cycle of the signal transfer from the sensor such as the position sensor to the control device is performed in the same cycle in all processes in one molding cycle corresponding to the scan cycle of the sensor. However, if the sensor scan cycle is shortened in order to perform more accurate control, signal transfer sent to the control device may be hindered due to communication speed limitations. This is particularly noticeable when signal transfer is performed from a plurality of position sensors to one signal input unit of one control device via the same communication line. In response to the problem that hinders the signal transfer from these sensors to the control device, when trying to construct a hardware configuration of the control device and the communication system, the cost of the control device becomes too high. It was.

The thing described in patent document 1 as a thing corresponding to these problems is known. In Patent Document 1, among the first section including the injection process, the second section including the pressure holding process and the cooling process, and the third section including the mold opening process and the protruding process, the sampling time of the operation state of the first section is the most. It also describes that the sampling time for the operating state in the second section should be shortened and then shortened, and as a result, the total number of samplings can be greatly reduced and the memory can be reduced in size and cost. Has been.

Japanese Examined Patent Publication No. 6-43087 (Claim 1, FIG. 1)

However, although the method described in Patent Document 1 varies the sampling time for each section, there is no description about the control of each operation unit. Therefore, high-precision measurement and data transfer are performed in the section where the sampling time is the shortest, but there is a problem that the measurement accuracy is low in the section where the sampling time is long. More specifically, in an injection molding machine, it is certain that the section including the injection process requires the most accurate measurement, but the mold opening / closing operation and ejector protruding operation are also highly accurate in each operating part. Control is desired. However, in the case of Patent Document 1, it is impossible to perform highly accurate measurement and control for the control of these operating parts.

In the present invention, in view of the above problems, an injection molding machine capable of satisfactorily transmitting a signal from a sensor to a control device over a plurality of steps of the injection molding machine by a relatively simple method or a relatively low cost apparatus. An object is to provide a control method and an injection molding machine.

The method of controlling an injection molding machine according to claim 1 of the present invention is a method of controlling an injection molding machine that performs closed loop control of a plurality of processes by transmitting operation information detected by a sensor to a control device. The transmission cycle from the sensor that detects the operation information mainly used for control to the control device is relatively shorter than the transmission cycle from other sensors to the control device.

According to a second aspect of the present invention, there is provided a method for controlling an injection molding machine, wherein the operation information detected by the sensor is transmitted to the control device to perform closed loop control of a plurality of steps. The transmission period from the sensor which detects the operation part of an action | operation state among action | operation parts to a control apparatus is made relatively shorter than the transmission period from another sensor to a control apparatus, It is characterized by the above-mentioned.

According to a third aspect of the present invention, there is provided a method for controlling an injection molding machine according to the first or second aspect, wherein the sensor includes at least a sensor for detecting a screw position of the injection device and a movable platen of the mold clamping device. It includes a sensor that detects the position and a sensor that detects the position of the ejector movable part of the mold clamping device. In the injection process, the transmission cycle from the sensor that detects the screw position to the control device is compared with the transmission cycle of other sensors. Therefore, in the mold opening process and mold closing process, the transmission cycle from the sensor that detects the position of the movable platen to the control device is relatively short compared to the transmission cycle of other sensors. In the process, the transmission cycle from the sensor that detects the position of the ejector movable portion to the control device is relatively shorter than the transmission cycle of other sensors.

An injection molding machine according to claim 4 of the present invention is an injection molding machine that performs closed loop control of a plurality of processes by transmitting operation information detected by a sensor to a control device, and is mainly used for control in each process. From the sensor that detects the operating part of the operating state among the plurality of operating parts, the transmission period from the sensor that detects the operation information to the control apparatus is set to be relatively shorter than the transmission period from the other sensors to the control apparatus. The transmission cycle to the control device is characterized by being relatively shorter than the transmission cycle from other sensors to the control device.

An injection molding machine according to the present invention is a sensor that detects operation information mainly used for control in each process in an injection molding machine that performs closed loop control of a plurality of processes by transmitting operation information detected by a sensor to a control device. The transmission cycle from the sensor to the control device is set to be relatively shorter than the transmission cycle from the other sensors to the control device, or the transmission cycle from the sensor that detects the operating unit in the operating state among the plurality of operating units to the control device Is relatively shorter than the transmission cycle from the other sensors to the control device, so that signal transmission from the plurality of sensors to the control device can be satisfactorily performed over each step of the injection molding machine.

It is a side view of the injection molding machine of the embodiment of the present invention. It is a block diagram of the control apparatus of the injection molding machine of embodiment of this invention. It is a figure which shows the transmission cycle (the frequency | count of transmission per time) of the position sensor in each process of embodiment of this invention. It is a figure which shows the transmission period of each position sensor of the injection | emission process of embodiment of this invention.

An injection compression molding machine 11 according to an embodiment of the present invention will be described with reference to FIG. The injection molding machine 11 includes a basic portion including an injection device 13 provided on one side of the base 12 and a mold clamping device 14 provided on the other side. In the injection device 13, a nozzle 17 is fixed in front of a heating cylinder 16 containing a screw 15 that can move forward and backward. The injection device 13 includes an injection hydraulic cylinder 18 that controls the screw 15 to move forward during injection and a back pressure control during measurement, and a measurement hydraulic motor 19 that controls rotation of the screw 15 during measurement. The hydraulic circuit to the injection hydraulic cylinder 18 and the metering hydraulic motor 19 is not shown, but a hydraulic sensor for controlling the back pressure at the time of metering is provided on the pipe line from the pump to the injection hydraulic cylinder 18. Further, between the front plate 20 and the screw 15 of the injection device 13, between the base portion 21 and the screw 15 of the injection device 13, between the front plate 20 and the pusher plate 22 provided with the metering motor 19, or the injection device 13. A position sensor 23 for detecting the position of the screw 15 which is an operating part is attached between any of the base 21 and the pusher plate 22. (In the above, the screw 15 includes the base shaft portion 15a of the screw 15 or a member connected to the base shaft portion 15a.)

In the present embodiment, as the position sensor 23 (sensor), an MTS sensor (registered trademark) that is a magnetostrictive absolute linear position sensor is used. A main body 23 a having a signal transmission function of the position sensor 23 is attached to the front plate 20, a linear bar-shaped scale portion 23 b is provided in parallel with the base shaft portion 15 a of the screw 15, and is connected to the base shaft portion 15 a of the screw 15. A magnet ring 23c as a reading unit is attached to the member. And the position sensor 23 of this embodiment has the signal processing part which includes a timer function in the main-body part 23a. Therefore, a signal is not transmitted by a request from the timer side of the control device 24. Here, the normal transmission cycle from the position sensor 23 to the control device 24 is 2.0 ms. However, the position sensor 23 has a function of changing the transmission cycle by a communication command. In the position sensor 23 of the present embodiment, the transmission cycle can be shortened to 0.5 ms. However, the type of position sensor 23 may be other non-contact type sensors or contact type sensors in addition to the magnetostrictive type, and may further be a sensor such as an encoder or potentiometer that detects the number of pulses. It is not limited. Further, the normal transmission cycle and the shortenable transmission cycle of the position sensor 23 are not limited.

The injection device 13 may be one in which at least one of the injection hydraulic cylinder 18 and the metering hydraulic motor 19 is driven by an electric motor such as a servo motor. When an injection servomotor is used for the forward / backward movement of the screw 15, the position of the screw 15 in the forward / backward direction is detected by a rotary encoder (a sensor for detecting the position) provided in the injection servomotor. .

The mold clamping device 14 will be described. A fixed plate 26 to which the fixed mold 25 is attached is erected on the base 12. A pressure receiving plate 27 is erected on the base 12 on the base 12 closer to the fixed plate 26 (on the reflection device side). The fixed plate 26 and the pressure receiving plate 27 are connected by tie bars 28 in the vicinity of the four corners, and are fixed by nuts. A movable plate 30 with a movable mold 29 attached is provided between the fixed plate 26 and the pressure receiving plate 27 so as to be guided by a tie bar 28 and movable in the mold opening / closing direction.

A hydraulic mold clamping cylinder 31 serving as a mold clamping mechanism and a mold opening / closing mechanism is attached to the pressure receiving plate 27, and a ram 32 of the mold clamping cylinder 31 is fixed to the back surface of the movable plate 30. Although the description of the hydraulic circuit of the mold clamping cylinder 31 is omitted, a hydraulic sensor or the like for controlling the mold clamping force at the time of mold clamping is provided on the pipe line from the pump to the mold clamping cylinder 31. The operating unit extends between any one of the pressure receiving plate 27 and the movable platen 30, between the base 12 and the movable platen 30, between the fixed platen 26 and the movable platen 30, and between the fixed die 25 and the movable die 29. A position sensor 33 (sensor) for detecting the position of the movable plate 30 is provided. The position sensor 33 has a main body 33a to which a signal line is connected attached to the pressure receiving board 27 side, a scale 33b attached to the main body 33a in the mold opening / closing direction, and a reading section 33c provided to the movable board 30 side. Yes. However, the position sensor 33 may have the main body portion 33a and the reading portion 33c attached to opposite boards. As the position sensor 33, a magnetostrictive sensor is used as in the injection device 13, but other types of sensors may be used.

The mold clamping device 14 may be of a toggle type, and the driving means at that time may be a hydraulic cylinder or an electric motor such as a servo motor. When the driving means is an electric motor other than a hydraulic cylinder or servo motor, the position sensor 33 is attached as described above. In the case of a servo motor, a rotary encoder provided in the servo motor serves as a position sensor for detecting the position of the movable platen (crosshead position). Further, the mold clamping device 14 may be a two-platen type mold clamping device provided with a mold clamping cylinder in which four tie bar shafts constitute a rod. In that case, a position sensor for detecting the position of the clamping cylinder (position of the tie bar) is also provided. For the purpose of performing parallel control by individually controlling the mold clamping cylinders, position sensors are provided corresponding to the number of mold clamping cylinders. Further, when injection compression molding or high-precision molding is performed, a position sensor for measuring the distance between the fixed mold and the movable mold may be provided.

A hydraulic cylinder 35 that is a drive means of an ejector device 34 for projecting the molded product P from the cavity surface of the movable mold 29 is located inside the ram 32 on the back side of the movable platen 30 or inside or near the movable platen 30. Installed. The rod of the hydraulic cylinder 35 is in contact with or fixed to the back surface of the ejector plate 36 in the movable mold 29. An ejector pin 37 is provided on the front side of the ejector plate 36, and the ejector pin 37 faces the cavity surface 29a. Further, a spring 38 is provided on the front surface of the ejector plate 36, and when the driving force of the hydraulic cylinder 35 is not exerted, the ejector pin 37 is retracted to the cavity surface 29a. The ejector device 34 is provided with a magnetostrictive position sensor 39 (sensor) so that the position of an ejector movable part (actuating part) such as an ejector plate 36, an ejector pin 37, and a rod of a hydraulic cylinder 35 is detected. It has become. The position and type of the position sensor 39 are not limited as in the injection device 13 and the like. Further, the drive means of the ejector device 34 is not limited to a hydraulic cylinder, and an electric motor such as a servo motor may be used. When a servo motor is used, a rotary encoder attached to the servo motor serves as a sensor for detecting the position of the ejector movable portion.

Next, the control device 24 of the injection molding machine will be described with reference to the block diagram of FIG. The control device 24 includes an arithmetic processing unit 40 that processes signals from sensors such as the position sensors 23, 33, and 39 to perform closed loop control and the like in sequence control. Further, a drive unit control unit 41 is provided which is connected to the arithmetic processing unit 40 and transmits a signal for controlling an electric motor such as a solenoid of a hydraulic circuit or a servo motor of a pump. Further, a display processing unit 42 for displaying a screen, a setting input unit 43 for inputting data, and a storage unit 44 for storing molding conditions and molding data are connected to the arithmetic processing unit 40. The arithmetic processing unit 40 of the control device 24 is provided with a sensor transmission cycle control unit 45 that controls the transmission cycle of the position sensors 23, 33, and 39. The arithmetic processing unit 40 and the sensor transmission cycle control unit 45 perform input processing (reading processing) on signals transmitted from the position sensors 23, 33, and 39 and set transmission cycles for the position sensors 23, 33, and 39. A sensor signal input / output processing unit 46 that performs output processing when transmitting is provided.

In the present embodiment, the sensor signal input / output processing unit 46 of the control device 24 includes a single connection port. The magnetostrictive position sensors 23, 33, 39 and the control device 24 are connected by CAN communication (Controller Area Network). The CAN communication is a well-known serial communication conforming to the ISO standard. In CAN communication, two communication lines (buses), CANhigh and CANlow, are paired to determine the bus level based on the operating voltage, and information is transmitted as a digital signal. In this embodiment, the communication speed of CAN communication is 500 kbps, but there may be other communication speeds. The communication means may be other digital communication or the like. For example, SSI, Profibus-DP, EtherCAT, EtherNet / IP, Powerlink, etc. may be used.

In the present embodiment, the signal lines 47 and 48.49 from the plurality of position sensors 23, 33, and 39 are integrated in the middle, and are connected to one connection port of the sensor signal input / output processing unit 46 as one signal line 50. It is connected. Therefore, the control device 24 does not need to include a control panel having a plurality of connection ports or a plurality of control panels having a connection port, and can be configured at low cost. The present invention does not exclude what has two communication lines and two connection ports in order to increase the transmission speed.

Next, the operation of each process in one molding cycle of the injection molding machine 11 of the present embodiment, signal transmission from the position sensors 23, 33, 39 to the control device 24, etc. will be described with reference to FIGS. In the present invention, when the operation information detected by the sensor is transmitted to the control device 24 and the closed loop control of a plurality of processes is performed, the operation information mainly used for control in each process is detected from the sensor to the control device. The transmission cycle is made relatively shorter than the transmission cycle from other sensors to the control device. FIG. 3 shows the transmission cycle (number of transmissions per time) of the position sensor in each process, and indicates that the transmission cycle is shorter as the height of the broken line is higher. Also, in the above, “operation information mainly used for control in each process” refers to operation information of an operation part that needs to perform closed-loop control with the highest accuracy in each process, and usually moves at the highest speed in each process. Indicates the position information (including speed information) of the actuating unit to be operated.

More specifically, the position sensor 23 that detects the position of the screw 15 during the operation of the screw 15 in the injection process (injection filling + holding pressure) and the subsequent weighing process provides operation information mainly used for control in these processes. It becomes the sensor 23 to detect. Then, as shown in FIG. 4, the transmission cycle from the position sensor 23 to the control device 24 is relatively shortened to 0.5 ms as compared with the transmission cycle of the other position sensors 33 and 39. The other sensors in the injection process refer to sensors 33 and 39 that detect operation information that is not mainly used for control in the process. The state of the operation part detected by these sensors 33 and 39 is a state which has stopped or does not require precise control. Further, a pressure sensor (not shown) of the mold clamping cylinder 31 does not need to perform high-density closed-loop control signal transmission in a short time, and corresponds mainly to a sensor that is not used for control.

A command for shortening the transmission cycle of the position sensor 23 is sent from the sensor transmission cycle control unit 45 of the control device 24 via the sensor signal input / output processing unit 46 simultaneously with the start of the injection process or within a predetermined time before that. The signal is transmitted to the main body 23 a having the signal transmission function of the position sensor 23 through the signal lines 50 and 47. As a result, the transmission cycle from the position sensor 23 to the control device 24 is switched from 2.0 ms to 0.5 ms. At this time, the transmission cycle of other position sensors such as the position sensor 33 that detects the position of the movable platen 30 and the position sensor 39 that detects the position of the ejector movable part remains 2.0 ms. Note that a certain amount of time is required for reading the signals from these position sensors 23, 33, 39 to the control device 24.

As a result, the signal lines 47, 48, 49 from the plurality of position sensors 23, 33, 39 are integrated on the way and connected as one signal line 50 to the connection port of the sensor signal input / output processing unit 46. However, there is no stagnation in the transmission cycle of the signal transmitted from the position sensor 23 that detects the position of the screw 15 to the control device 24. Accordingly, the position information (movement information) of the screw 15 in the injection process is input to the control device 24 with high density, and closed loop control such as injection filling, holding pressure, back pressure, etc. performed using the injection hydraulic cylinder 18 is performed. Can increase the responsiveness. When the injection process and the metering process are completed, the transmission cycle of the position sensor 23 is temporarily reduced to 2.0 ms by a command from the sensor transmission cycle control unit 45.

In FIG. 4, the signals transmitted from the respective position sensors 23, 33, 39 to the control device 24 do not overlap in reading time. However, when signals from the other position sensors 33 and 39 are transmitted and received by the control device 24 while reading the signal from the position sensor 23, the position for detecting the position of the screw 15 whose transmission cycle is shortened. The reading of the signal transmitted from the sensor 23 to the control device 24 is prioritized, and the signals from the other position sensors 33 and 39 are deleted without being read. When the signal from the position sensor 23 is transmitted and overlapped while reading the signal from the position sensor 33 or 39, the signal from the position 23 is read after reading the position sensor 33 and the like. Therefore, the signal from the position sensor 23 is read every time without being deleted. The position sensors 23, 33, and 39 that are prioritized may be the position sensor 23 that detects the position of the screw 15 throughout one molding cycle, or signals from the position sensors 23, 33, and 39 whose transmission cycle is shortened. May be prioritized. Further, the processing method in the case of overlapping signals is not limited to the above, and other methods may be used.

In the metering process subsequent to the injection process, the cooling process is performed on the mold clamping device 14 side with the mold clamping cylinder 31 being pressurized. Continuing with the measuring process, the transmission cycle from the position sensor 23 that detects the position of the screw 15 to the control device 24 is continuously shortened to 0.5 ms. In the cooling process, since the position control of the movable platen 30 is not regarded as important, the transmission cycle of the position sensor 33 may be long. The transmission cycle from the position sensor 23 that detects the position of the screw 15 to the control device 24 may be shortened only in the injection process or only in the injection filling process in the injection process. In that case, in the pressure holding process, the transmission cycle from the sensor for measuring the injection pressure, such as a load cell or a hydraulic pressure sensor, to the control device 24 may be shortened. In the present invention, a plurality of steps are sequentially performed. However, an example in which a plurality of steps are performed in parallel, such as the measuring step and the cooling step, is included.

When the movable plate 30 is operated in the mold opening process after the cooling process is completed, the control device is operated from the position sensor 33 that detects the position of the movable plate 30 that is a sensor that detects operation information mainly used for control in the mold opening process. The transmission period to 24 is relatively shortened compared with the transmission periods of the other sensors 23 and 39 to shorten it to 0.5 ms. Further, the transmission cycle of the position sensor 39 for detecting the position of the ejector operating portion remains 2.0 ms as in the injection process. Therefore, as in the case of the injection, even if a signal is transmitted to the connection port of the sensor signal input / output processing unit 46 through one signal line 50, the position sensor 33 detects the position of the movable platen 30 and the control device. No stagnation of the signal transmitted to 24 occurs. Thereby, the movement information of the movable platen 30 in the mold opening process is input to the control device 24 with high density, and the responsiveness of the closed-loop control of the mold clamping cylinder 31 for moving the movable platen 30 can be enhanced. When the mold opening process is completed, the transmission cycle of the position sensor 33 is temporarily reduced to 2.0 ms by a command from the sensor transmission cycle control unit 45.

In addition, after the mold is opened, a position sensor 39 that detects the position of the ejector movable part such as the ejector plate 36 and the ejector pin 37 when the ejector is operated in the projecting process of the molded product (a sensor that detects operation information mainly used for control in the projecting process). The transmission cycle from the control device 24 to the control device 24 is relatively short compared with the transmission cycles of the other sensors 23 and 33, and is shortened to 0.5 ms. At this time, the transmission cycle of the other position sensors 23 and 33 is 2.0 ms as described above. As a result, the signal transmitted from the position sensor 39 to the control device 24 does not stagnate, and movement information of the ejector movable portion in the protruding process of the molded product is input to the control device 24 with high density, and the ejector operation is closed. The responsiveness of the hydraulic cylinder 35 that performs loop control can be improved. When the molded product projecting step is completed, the transmission cycle of the position sensor 39 is temporarily reduced to 2.0 ms by a command from the sensor transmission cycle control unit 45.

As for the next mold closing process, as in the mold opening process, only the transmission cycle of the position sensor 33 is shortened to 0.5 ms as a sensor for detecting operation information mainly used for control by a command from the sensor transmission cycle control unit 45. Control. When the mold closing process is completed, the transmission cycle of the position sensor 33 is returned to 2.0 ms. When the intermediate time has elapsed, the transmission cycle of the position sensor 23 that detects the position of the screw 15 is shortened, and the next injection process is started.

In the present embodiment, an example in which the transmission cycle of any one of the position sensors 23, 33, 39 is shortened between the three position sensors 23, 33, 39 has been described. However, the number of sensors of the present invention should be at least two, and there should be at least two corresponding work steps. In addition, the number of position sensors may be more than one such as a position sensor (not shown) for measuring the distance between the fixed mold 25 and the movable mold 29, or in combination with a plurality of position sensors in other combinations. An example of shortening the transmission cycle of the position sensor may be used. Specifically, a sensor that detects the rotation angle of the metering motor, a position sensor that detects the movement of the mold core, gate cutter, gate valve, etc., a strain sensor that detects mold clamping force and projectile force, and a resin pressure Among various sensors used in an injection molding machine, such as a resin pressure sensor and a pressure sensor for detecting hydraulic pressure, one that can change the transmission cycle is an object of the present invention.

The predetermined process of the injection molding machine may be the following process. A signal transmitted from the position sensor 33 that detects the position of the movable platen 30 to the control device 24 when molding is performed with the movement of the movable platen 30 in the compression process or foaming process during injection compression molding or foam molding. The transmission cycle may be shortened. Or you may make it shorten the transmission period of the signal transmitted to the control apparatus 24 from the position sensor for measuring the distance of the fixed metal mold | die 25 and the movable metal mold | die 29 mutually. In these cases, the transmission cycle of the signal transmitted from the position sensor 23 that detects the position of the screw 15 of the injection device 13 to the control device 24 may be kept short, or the shortening may be canceled. When the transmission cycle of the position sensor 33 of the screw 15 together with the position sensor 33 of the movable plate 30 is also shortened, the signal of the shortened transmission cycle is sent to the signal line 50 at the same time. However, there is no problem if the transmission cycle can be shortened to such an extent that the signal transmission does not stay. Even if signal transmission stays slightly, it can be shortened from the initial transmission cycle (for example, 2.0 ms), and it is often desirable to put it into practical use when the transmission cycle required for control is satisfied. In this embodiment, the transmission cycle from the sensor other than the sensor that mainly detects the operation information used for control to the control device is constant (for example, 2.0 ms) in the initial state, but is further delayed. May be provided.

Also, in the present invention, the sensor that changes the transmission cycle of the sensor in each process is not from the start of the process, but before the end of the previous process by the timer, or the transmission cycle is shortened from the middle of the process. Including. Further, the extension of the transmission cycle may not be coincident at the end of the process, but may be extended during the process (before the end) or after the start of the next process. In the present invention, “transmission cycle from the sensor that detects operation information mainly used for control in each step to the control device is“ relatively shorter ”than the transmission cycle from other sensors to the control device” A case in which the initial transmission cycle from a plurality of sensors to the control device 24 is all set to the shortest, and a similar state is created by delaying the transmission cycle of the sensor that does not require the shortest transmission cycle in each process. Is included.

Furthermore, the present invention does not shorten the transmission cycle according to the process (time), but from a sensor that detects an operating part among a plurality of operating parts (for example, a screw, a movable plate, and an ejector driving part) to a control device. The transmission cycle may be relatively shorter than the transmission cycle from other sensors to the control device. Specifically, a transmission cycle that shortens the transmission cycle simultaneously with the detection of the operation of the operation unit, or a transmission cycle of the position sensor that detects the speed when the operation unit speed exceeds a certain level, It may be shorter than the transmission cycle of the other sensor that detects. Similarly, the transmission cycle may be extended at the same time as the operation unit is stopped, or the transmission cycle may be extended by detecting that the speed of the operation unit is below a certain level. In addition, the operation part which is not in an operation state in the above includes the thing which does not need to perform highly accurate closed loop control even if there is a slight operation actual condition.

Although the present invention is not enumerated one by one, it is not limited to the present embodiment described above, and it goes without saying that the present invention can be applied to those modified by a person skilled in the art based on the spirit of the present invention. That is. The injection molding machine may be a vertical type other than the horizontal type. Furthermore, the material used for the injection molding machine is not limited to resin, but may be a mixture of resin and other materials, metal, other organic matter, or inorganic matter.

DESCRIPTION OF SYMBOLS 11 Injection molding machine 13 Injection apparatus 14 Clamping apparatus 15 Screw 18 Injection hydraulic cylinders 23, 33, 39 Position sensor 24 Control apparatus 30 Movable platen 31 Clamping cylinder 34 Ejector apparatus 40 Arithmetic processing section 45 Sensor transmission cycle control section 46 Sensor Signal input / output processing unit 47, 48, 49, 50 Signal line

Claims (4)

In a control method of an injection molding machine that performs closed loop control of a plurality of processes by transmitting operation information detected by a sensor to a control device,
A method for controlling an injection molding machine, characterized in that a transmission cycle from a sensor that detects operation information mainly used for control in each step to a control device is relatively shorter than a transmission cycle from another sensor to the control device. . In a control method of an injection molding machine that performs closed loop control of a plurality of processes by transmitting operation information detected by a sensor to a control device,
Control of an injection molding machine characterized in that a transmission cycle from a sensor that detects an active portion of a plurality of operating portions to a control device is relatively shorter than a transmission cycle from other sensors to the control device Method. The sensor includes at least a sensor for detecting the position of the screw of the injection device, a sensor for detecting the position of the movable platen of the mold clamping device, and a sensor for detecting the position of the ejector movable part of the mold clamping device,
In the injection process, the transmission cycle from the sensor that detects the position of the screw to the control device is relatively short compared to the transmission cycle of other sensors,
In the mold opening process and the mold closing process, the transmission cycle from the sensor that detects the position of the movable platen to the control device is made relatively shorter than the transmission cycle of other sensors,
3. The projecting step of claim 1, wherein a transmission cycle from a sensor that detects the position of the ejector movable portion to the control device is relatively shorter than a transmission cycle of another sensor. Method of injection molding machine. In an injection molding machine that performs closed loop control of a plurality of processes by transmitting operation information detected by a sensor to a control device,
The transmission cycle from the sensor that detects operation information mainly used for control in each process to the control device is made relatively shorter than the transmission cycle from other sensors to the control device, or the operation state among a plurality of operation units An injection molding machine characterized in that a transmission cycle from a sensor that detects the actuating portion to the control device is relatively shorter than a transmission cycle from another sensor to the control device.