CN107127940B - Injection molding machine - Google Patents

Abstract

The invention provides an injection molding machine, which ensures the compatibility of the setting of the injection molding machine under the condition that the structures of the injection molding machine are different. The injection molding machine of the present invention comprises: and a control device that generates an operation amount of a part to be controlled based on a set value of a control amount indicating a molding condition and a detected value of the control amount, the control amount and the operation amount having a relationship different depending on a difference in structure of the injection molding machine, wherein when the operation amount in a case where the structure is the current structure is generated using the set value in a case where the structure is another structure different from the current structure, the control device corrects the detected value based on the difference in structure between the another structure and the current structure, and generates the operation amount based on the corrected detected value and the set value.

Description

Injection molding machine

Technical Field

The present application claims priority based on japanese patent application No. 2016-. The entire contents of this Japanese application are incorporated by reference into this specification.

The present invention relates to an injection molding machine.

Background

The injection molding machine described in patent document 1 includes a unit conversion mechanism for converting a set unit of a condition item, which differs for each model according to a screw diameter, into a unit common to each model regardless of the screw diameter. For example, the unit conversion member converts the unit mm of the injection position into the unit cc of the injection amount. And, the unit converting member converts the unit of the injection speed from mm/sec to cc/sec. The trouble of resetting the molding conditions by the operator through manual work can be eliminated.

Patent document 1: japanese patent No. 3701907

When the structure of the injection molding machine is changed, the setting of the injection molding machine needs to be changed due to differences in frictional resistance, inertia, control responsiveness, and the like, but the setting of the injection molding machine may not be changed depending on the situation of the user.

Disclosure of Invention

The present invention has been made in view of the above problems, and a main object thereof is to provide an injection molding machine that ensures compatibility of setting of the injection molding machine when the injection molding machine has a different structure.

In order to solve the above problem, according to an aspect of the present invention, there is provided an injection molding machine including: a control device for generating an operation amount of a part to be controlled based on a set value of a control amount indicating a molding condition and a detected value of the control amount,

the control amount and the operation amount have different relationships according to structural differences of the injection molding machine,

when the manipulated variable in the present configuration is generated using the set value in the case where the configuration is another configuration than the present configuration, the control device corrects the detected value based on a configuration difference between the another configuration and the present configuration, and generates the manipulated variable based on the corrected detected value and the set value.

Effects of the invention

According to an aspect of the present invention, there is provided an injection molding machine that ensures compatibility of injection molding machine settings in the case where the structures of the injection molding machines are different.

Drawings

Fig. 1 is a diagram showing a state at the end of mold opening of an injection molding machine according to an embodiment.

Fig. 2 is a diagram showing a state of the injection molding machine according to the embodiment at the time of mold clamping.

Fig. 3 is a diagram showing an operation screen of the injection molding machine according to the embodiment.

Fig. 4 is a diagram showing a relationship among the screw back pressure, the pressure of the molding material, and the frictional resistance in the metering step according to the embodiment.

Fig. 5 is a diagram showing a relationship among a heating amount of a cylinder by a heater, a heat transfer amount from the cylinder to a molding material, and a moving heat amount from the cylinder to a cooler in injection molding according to an embodiment.

In the figure: 2-injection molding machine, 4-network, 10-mold clamping device, 12-fixed platen, 13-movable platen, 15-auxiliary platen, 20-toggle mechanism, 21-mold clamping motor, 40-injection device, 41-cylinder, 41 b-heat insulation ring, 42-nozzle, 43-screw, 45-metering motor, 46-injection motor, 47-pressure detector, 50-ejection device, 51-ejection motor, 52-motion conversion mechanism, 53-ejection rod, 90-control device, 95-input device, 96-output device, 100-operation picture.

Detailed Description

Hereinafter, the embodiments for carrying out the present invention will be described with reference to the drawings, but the same or corresponding components are denoted by the same or corresponding reference numerals in the drawings, and the description thereof will be omitted.

Fig. 1 is a diagram showing a state at the end of mold opening of an injection molding machine according to an embodiment. Fig. 2 is a diagram showing a state of the injection molding machine according to the embodiment at the time of mold clamping. As shown in fig. 1 and 2, the injection molding machine 2 includes a frame Fr, a mold clamping device 10, an injection device 40, an ejector device 50, a control device 90, an input device 95, and an output device 96.

First, the mold apparatus 10 and the ejector apparatus 50 will be described. In the description of the mold clamping apparatus 10 and the like, the moving direction of the movable platen 13 when the mold is closed (the right direction in fig. 1 and 2) is set to the front, and the moving direction of the movable platen 13 when the mold is opened (the left direction in fig. 1 and 2) is set to the rear.

The mold clamping device 10 closes, clamps, and opens the mold of the mold device 30. The mold clamping device 10 includes a fixed platen 12, a movable platen 13, an auxiliary platen 15, a tie bar 16, a toggle mechanism 20, a mold clamping motor 21, and a motion conversion mechanism 25.

The fixed platen 12 is fixed to the frame Fr. A fixed mold 32 is attached to a surface of the fixed platen 12 facing the movable platen 13.

The movable platen 13 is movable along a guide (e.g., a guide rail) 17 laid on the frame Fr, and is movable forward and backward with respect to the fixed platen 12. A movable mold 33 is attached to a surface of the movable platen 13 facing the fixed platen 12.

The movable platen 13 is moved forward and backward with respect to the fixed platen 12, thereby closing, clamping, and opening the mold. The stationary mold 32 and the movable mold 33 constitute a mold apparatus 30.

The auxiliary presser 15 is connected to the fixed presser 12 with a gap therebetween, and is mounted on the frame Fr so as to be movable in the mold opening and closing direction. The auxiliary platen 15 may be movable along a guide laid on the frame Fr. The guide of the auxiliary platen 15 may also be shared with the guide 17 of the movable platen 13.

In the present embodiment, the fixed platen 12 is fixed to the frame Fr, and the auxiliary platen 15 is movable in the mold opening and closing direction on the frame Fr, but the auxiliary platen 15 may be fixed to the frame Fr, and the fixed platen 12 may be movable in the mold opening and closing direction on the frame Fr.

The connecting rod 16 connects the fixed platen 12 and the auxiliary platen 15 with a gap therebetween. A plurality of the connecting rods 16 may be used. Each tie bar 16 extends parallel to the mold opening and closing direction and in accordance with the mold clamping force. A mold clamping force detector 18 is provided on at least one tie bar 16. The mold clamping force detector 18 detects the mold clamping force by detecting the strain of the tie bar 16, and transmits a signal indicating the detection result to the control device 90.

The mold clamping force detector 18 is not limited to the strain gauge type, and may be of a piezoelectric type, a capacitive type, a hydraulic type, an electromagnetic type, or the like, and the attachment position thereof is not limited to the tie bar 16.

The toggle mechanism 20 moves the movable platen 13 relative to the fixed platen 12. The toggle mechanism 20 is disposed between the movable platen 13 and the auxiliary platen 15. The toggle mechanism 20 includes a crosshead 20a, a pair of links, and the like. Each link group includes a plurality of links 20b and 20c telescopically coupled by pins or the like. One link 20b is attached to the movable platen 13 so as to be swingable, and the other link 20c is attached to the auxiliary platen 15 so as to be swingable. When the crosshead 20a is advanced and retreated, the plurality of links 20b and 20c extend and contract, and the movable platen 13 is advanced and retreated with respect to the auxiliary platen 15.

The mold clamping motor 21 is attached to the auxiliary platen 15 and operates the toggle mechanism 20. The mold clamping motor 21 extends and contracts the links 20b and 20c by advancing and retreating the crosshead 20a, thereby advancing and retreating the movable platen 13.

The motion conversion mechanism 25 converts the rotational motion of the mold clamping motor 21 into a linear motion and transmits the linear motion to the crosshead 20 a. The motion conversion mechanism 25 is constituted by, for example, a ball screw mechanism or the like.

The operation of the mold clamping device 10 is controlled by a control device 90. The controller 90 controls the mold closing process, mold opening process, and the like.

In the mold closing step, the movable platen 13 is moved forward by driving the mold clamping motor 21 to move the crosshead 20a forward at a set speed, and the movable mold 33 is brought into contact with the fixed mold 32. The position and speed of the crosshead 20a are detected by, for example, an encoder 21a of the mold clamping motor 21. A signal indicating the detection result is sent to the control device 90.

In the mold clamping step, the mold clamping motor 21 is further driven to further advance the crosshead 20a to the set position, thereby generating a mold clamping force. When the mold is closed, a cavity space 34 is formed between the movable mold 33 and the fixed mold 32, and the cavity space 34 is filled with a liquid molding material. The filled molding material is cured to obtain a molded article. The number of cavity spaces 34 may be plural, and in this case, plural molded articles can be obtained at the same time.

In the mold opening step, the movable platen 13 is moved backward to separate the movable mold 33 from the fixed mold 32 by driving the mold clamping motor 21 to move the crosshead 20a backward at a set speed.

Further, the mold clamping device 10 of the present embodiment includes the mold clamping motor 21 as a driving source, but may include a hydraulic cylinder instead of the mold clamping motor 21. The mold clamping device 10 may have a linear motor for opening and closing the mold, or may have an electromagnet for clamping the mold.

The mold clamping device 10 of the present embodiment is a horizontal type in which the mold opening/closing direction is the horizontal direction, but may be a vertical type in which the mold opening/closing direction is the vertical direction.

The ejector 50 ejects the molded product from the mold device 30. The ejector 50 includes an ejector motor 51, a motion conversion mechanism 52, and an ejector rod 53.

The ejector motor 51 is attached to the movable platen 13. The ejector motor 51 is directly connected to the motion conversion mechanism 52, but may be connected to the motion conversion mechanism 52 via a belt or a pulley.

The motion conversion mechanism 52 converts the rotational motion of the ejector motor 51 into the linear motion of the ejector rod 53. The motion conversion mechanism 52 is constituted by, for example, a ball screw mechanism or the like.

The ejector rod 53 is freely movable forward and backward in the through hole of the movable platen 13. The tip end of the ejector rod 53 contacts the movable member 35 disposed in the movable mold 33 so as to be movable forward and backward. The ejector rod 53 may be connected to the movable member 35.

The operation of the ejector 50 is controlled by the control device 90. The control device 90 controls the ejection process and the like.

In the ejection step, the ejector motor 51 is driven to advance the ejector rod 53, thereby advancing the movable member 35 to eject the molded product. Then, the ejector motor 51 is driven to retract the ejector rod 53, and the movable member 35 is retracted to the original position. The position and speed of the ejector rod 53 are detected by, for example, an encoder 51a of the ejector motor 51. A signal indicating the detection result is sent to the control device 90.

Next, the injection device 40 will be explained. In the explanation of the injection device 40, unlike the explanation of the mold clamping device 10, the moving direction of the screw 43 during filling (the left direction in fig. 1 and 2) is assumed to be the front side, and the moving direction of the screw 43 during metering (the right direction in fig. 1 and 2) is assumed to be the rear side.

The injection device 40 is provided on a slide base Sb which can advance and retreat with respect to the frame Fr, and can advance and retreat with respect to the mold device 30. The injection device 40 contacts the mold device 30 and fills the molding material in the mold device 30.

The injection device 40 includes, for example, a cylinder 41, a nozzle 42, a screw 43, a cooler 44, a metering motor 45, an injection motor 46, a pressure detector 47, a heater 48, and a temperature detector 49.

The cylinder 41 heats the molding material supplied from the supply port 41a to the inside. The supply port 41a is formed in the rear of the cylinder 41. A cooler 44 such as a water cooling cylinder is provided on the outer periphery of the rear portion of the cylinder block 41. A heater 48 such as a band heater and a temperature detector 49 are provided on the outer periphery of the cylinder 41 in front of the cooler 44.

The cylinder 41 is divided into a plurality of regions in the axial direction of the cylinder 41 (the left-right direction in fig. 1 and 2). A heater 48 and a temperature detector 49 are provided in each zone. The controller 90 controls the heater 48 so that the actual temperature measured by the temperature detector 49 becomes the set temperature for each zone.

The nozzle 42 is provided at the front end of the cylinder 41 and is pressed against the die apparatus 30. A heater 48 and a temperature detector 49 are provided on the outer periphery of the nozzle 42. The controller 90 controls the heater 48 so that the actual measured temperature of the nozzle 42 becomes the set temperature.

The screw 43 is rotatably and movably disposed in the cylinder 41.

The metering motor 45 rotates the screw 43 to feed the molding material forward along the spiral groove of the screw 43. The molding material is gradually melted by heat from the cylinder 41 while being sent forward. The screw 43 is retracted as the liquid molding material is fed forward of the screw 43 and accumulated in the front of the cylinder 41.

The injection motor 46 advances and retracts the screw 43. The injection motor 46 advances the screw 43 to inject the liquid molding material accumulated in front of the screw 43 from the cylinder 41 and fill the molding device 30 with the molding material. Then, the injection motor 46 presses the screw 43 forward, and applies pressure to the molding material in the mold device 30. The molding material of the insufficient portion can be supplemented. A motion conversion mechanism that converts the rotational motion of the injection motor 46 into the linear motion of the screw 43 is provided between the injection motor 46 and the screw 43. The motion conversion mechanism is constituted by a ball screw mechanism or the like.

The pressure detector 47 is disposed, for example, between the injection motor 46 and the screw 43, and detects the pressure applied to the screw 43 from the molding material, the back pressure applied to the screw 43, and the like. The pressure applied to the screw 43 from the molding material corresponds to the pressure applied to the molding material from the screw 43. The pressure detector 47 transmits a signal indicating the detection result thereof to the control device 90.

The action of the injection device 40 is controlled by a control device 90. The controller 90 controls the filling process, the pressure maintaining process, the metering process, and the like.

In the filling step, the injection motor 46 is driven to advance the screw 43 at a predetermined speed, and the molding material in a liquid state accumulated in front of the screw 43 is filled into the mold device 30. The position and speed of the screw 43 are detected, for example, by an encoder 46a of the injection motor 46. A signal indicating the detection result is sent to the control device 90. When the position of the screw 43 reaches the set position, switching from the filling step to the holding pressure step (so-called V/P switching) is performed. The set speed of the screw 43 may be changed according to the position and time of the screw 43, and the like.

In the filling step, after the position of the screw 43 reaches the set position, the screw 43 may be temporarily stopped at the set position, and then the V/P switching may be performed. Instead of stopping the screw 43, the screw 43 may be slightly advanced or slightly retracted immediately before the V/P switching.

In the pressure maintaining step, the injection motor 46 is driven to push the screw 43 forward at a set pressure, and pressure is applied to the molding material in the mold device 30. The molding material of the insufficient portion can be supplemented. The pressure of the molding material is detected by, for example, a pressure detector 47. A signal indicating the detection result is sent to the control device 90.

In the pressure retaining step, the molding material in the mold device 30 is gradually cooled, and the entrance of the cavity space 34 is closed by the solidified molding material at the end of the pressure retaining step. This state is called gate sealing, and prevents backflow of the molding material from the cavity space 34. After the pressure maintaining step, the cooling step is started. In the cooling step, the molding material in the cavity space 34 is solidified. In order to shorten the molding cycle, the metering step may be performed in the cooling step.

In the metering step, the metering motor 45 is driven to rotate the screw 43 at a set rotation speed, and the molding material is fed forward along the spiral groove of the screw 43. With this, the molding material gradually melts. The screw 43 is retracted as the liquid molding material is fed forward of the screw 43 and accumulated in the front of the cylinder 41. The rotational speed of the screw 43 is detected by an encoder 45a of the metering motor 45, for example. A signal indicating the detection result is sent to the control device 90.

In the metering step, the injection motor 46 is driven to apply a predetermined back pressure to the screw 43 in order to restrict rapid retraction of the screw 43. The back pressure against the screw 43 is detected by, for example, a pressure detector 47. A signal indicating the detection result is sent to the control device 90. When the screw 43 is retracted to the set position and a predetermined amount of the molding material is accumulated in front of the screw 43, the metering process is terminated.

The injection device 40 of the present embodiment is a coaxial screw type, but may be a premolded type. In the pre-injection type injection apparatus, a molding material melted in a plasticizing cylinder is supplied to an injection cylinder, and the molding material is injected from the injection cylinder into a mold apparatus. The screw is rotatably or rotatably disposed in the plasticizing cylinder and is movable forward and backward, and the plunger is rotatably disposed in the injection cylinder.

As shown in fig. 1 and 2, the control device 90 includes a cpu (central Processing unit)91, a storage medium 92 such as a memory, an input interface 93, and an output interface 94. The control device 90 performs various controls by causing the CPU91 to execute a program stored in the storage medium 92. The control device 90 receives a signal from the outside through the input interface 93 and transmits a signal to the outside through the output interface 94.

The input device 95 accepts an input operation by a user, and transmits an operation signal corresponding to the input operation by the user to the control device 90. As the input device 95, for example, a touch panel is used. The touch panel also serves as an output device 96 described later.

The output device 96 displays an operation screen corresponding to an input operation of the input device 95 under the control of the control device 90. The operation screen is displayed in a plurality of modes, either in a switching mode or in an overlapping mode.

The user operates the input device 95 while viewing the operation screen displayed on the output device 96 to set the mold clamping device 10, the injection device 40, the ejector, and the like. The settings are stored in the storage medium 92 and read out as necessary.

The control device 90 generates the operation amount of the controlled portion based on the set value of the control amount indicating the molding condition and the detected value of the control amount. As the part to be controlled, for example, an electric power device may be used, and a motor, a heater, or the like may be used.

The control device 90 may generate the operation amount of the controlled portion so that a difference between the set value of the controlled amount and the detected value of the controlled amount becomes zero. The control method of the present embodiment is feedback control, but may be feedforward control.

As the control quantity, for example, at least one physical quantity selected from force, pressure, torque, temperature, current, movement distance (e.g., rotational movement distance, linear movement distance), and load time is used alone or in combination. The combination may be any of sum, difference, product, and quotient, or a plurality of these. Examples of the combination include a product of the force and the movement distance, a product of the force and the load time, and a quotient (i.e., velocity) of the movement distance and the load time.

However, the injection molding machine 2 has a different structure depending on the model. Further, even if the injection molding machine 2 is of the same model, the injection molding machine may have a different structure in which an alternative component is mounted due to a stoppage of replacement of a component or the like. The control amount and the operation amount have different relationships depending on the structural differences of the injection molding machine 2. The relationship between the control amount and the operation amount is expressed by, for example, a transfer function.

For example, in the metering step, the relationship between the back pressure of the screw 43 (more specifically, the pressure of the molding material controlled by the back pressure of the screw 43) as the controlled amount and the supply current of the injection motor 46 as the operation amount is different depending on the difference in the structure of the peripheral devices because the relationship is affected by the frictional resistance of the peripheral devices. For example, if the frictional resistance of the peripheral device is small in the case where the supply current to the injection motor 46 is the same, the pressure of the molding material increases. As a case where the frictional resistance of the peripheral device becomes small, for example, a case where a seal member for preventing leakage of the lubricant is not required can be cited. The frictional resistance of the entire seal member is reduced by the amount of the lost frictional resistance.

Similarly, in the pressure maintaining step, the relationship between the pressure of the molding material as the controlled amount and the supply current of the injection motor 46 as the operation amount is different depending on the difference in the structure of the peripheral devices because the relationship is affected by the frictional resistance of the peripheral devices.

The relationship between the temperature of the cylinder 41 as a control amount (more specifically, the temperature of the molding material controlled by the temperature of the cylinder 41) and the supply current of the heater 48 as an operation amount differs according to the difference in the structure of the cylinder 41 and the like because the relationship is influenced by the heat transfer in the cylinder 41 and the like. For example, when the current supplied to the heater 48 is the same, the temperature of the molding material increases if the heat transfer from the heater 48 to the cooler 44 is restricted. As a case where the heat transfer is restricted, for example, a heat insulating ring 41b may be added to the cylinder 41 between the heater 48 and the cooler 44. The movement of heat can be restricted in the middle of the cylinder 41.

When the set value is generated using the configuration of the injection molding machine that is different from the current configuration, and the operation amount is generated when the configuration of the injection molding machine is the current configuration, the control device 90 corrects the detected value of the control amount based on the difference between the current configuration and the other configuration. The correction amount of the detection value is obtained by a preliminary test or the like, and the correction amount stored in the storage medium 92 is read and used. For example, when the controlled amount is the back pressure of the screw 43 in the metering step, the correction amount is determined so that the pressure of the molding material excluding the frictional resistance from the pressure detected by the pressure detector 47 becomes the same regardless of the difference in structure. Similarly, when the controlled amount is the pressure of the molding material in the pressure holding step, the correction amount is determined so that the pressure of the molding material excluding the frictional resistance from the pressure detected by the pressure detector 47 becomes the same regardless of the difference in structure. When the controlled amount is the temperature of the cylinder 41, the correction amount is determined so that the temperature of the molding material inside the cylinder 41 becomes the same regardless of the difference in structure. Whether the temperature of the molding material inside the cylinder 41 is the same or not can be checked by whether the torque of the metering motor 45 in the metering step is the same or not. This is because the viscosity and temperature of the molding material inside the cylinder 41 become the same when the torque of the metering motor 45 becomes the same.

The controller 90 generates the operation amount based on the corrected detection value and the set value. Therefore, when the injection molding machines 2, 2A, and 2B are different in structure, compatibility of setting of the injection molding machines 2, 2A, and 2B can be ensured. For example, when the same mold device 30 is mounted on each of the injection molding machines 2, 2A, and 2B, the setting does not need to be changed for each of the injection molding machines 2, 2A, and 2B, and the user can be satisfied. Further, even when the structure of the injection molding machine 2 is changed by replacing the entire injection molding machine 2 (changing the model), replacing a part of the injection molding machine 2, or the like, it is possible to use the old setting before replacement as it is while ensuring the compatibility of the setting.

The control device 90 may store correction amounts of the detected values for each candidate of the configuration of the injection molding machine 2 in advance, and when one candidate is selected from a plurality of candidates of the configuration, the detected value may be corrected by a correction amount corresponding to the selected configuration. For one candidate, multiple factors may be combined to determine. In addition, when the selected configuration is not another configuration but the current configuration, the correction amount is naturally zero.

The control device 90 may be connected to the other injection molding machines 2A, 2B via the network 4 or the like. The network 4 may be a wired network or a wireless network. Injection molding machine 2A has a structure a different from the current structure of injection molding machine 2, and injection molding machine 2B has a structure B different from the current structure of injection molding machine 2. The structure A and the structure B are different structures. The control device 90 can acquire combinations of the respective configurations and set values from the injection molding machines 2A, 2B. In this acquisition, a storage medium such as a memory card may be used, or the network 4 may not be used.

The control device 90 associates the configuration with the set value and stores the associated configuration in the storage medium 92. The control device 90 can automatically select a configuration associated with the currently set value based on the currently set value and information stored in the storage medium 92. It is possible to determine whether the currently set value is the value of the current configuration or the value of another configuration. The trouble of the user selecting the structure can be omitted and the wrong selection by the user can be prevented.

In the case where the operation amount of the injection molding machine having the current configuration is generated using the set value of the injection molding machine having the configuration different from the current configuration, the control device 90 may correct the detection value so that the predetermined physical amount different from the control amount is constant. For example, when the controlled variable is the temperature of the cylinder 41, the controller 90 corrects the detected value so that the torque of the measuring motor 45 in the measuring step becomes the same. This is because the torque of the measuring motor 45 indicates the viscosity and temperature of the molding material inside the cylinder 41.

Fig. 3 is a diagram showing an operation screen of the injection molding machine according to the embodiment. The operation screen 100 is used to correct the detection value. The operation screen 100 includes, for example, a control amount input field 101, a configuration input field 102, and an execution/cancellation selection field 103.

The control amount input field 101 is a field in which a user inputs a control amount indicating a molding condition. When the user touches the control amount input field 101, candidates for displaying the control amount can be popped up. The user can select the control amount from its candidates.

The configuration input field 102 is a field in which the user inputs a configuration corresponding to the set value of the control amount input in the control amount input field 101. If the user touches the structure input field 102, candidates for the display structure may pop up. The user can select a structure from its candidates.

The execution/cancellation selection field 103 is a field in which the user selects execution or cancellation of correction of the detected value of the control amount input through the control amount input field 101. Every time the user touches the control amount input field 101, display can be switched to "ON" indicating execution and "OFF" indicating cancellation.

The control device 90 corrects the detected value of the control amount in accordance with the user's input operation on the operation screen 100. In the case where the type of the control amount and the type of the configuration are predetermined, the control amount input field 101 and the configuration input field 102 may not be provided, but may be left.

The control device 90 may store in advance identification information such as the number and name of each user in the storage medium 92, the authority information relating to whether or not to permit the operation of the operation screen 100. The control device 90 acquires identification information of a user who operates the operation screen 100 by a reader or the like, and determines whether or not to permit the operation of the operation screen 100 based on the acquired identification information and information stored in advance in the storage medium 92. Only authorized users can operate the operation screen 100, and unauthorized users can be prohibited from operating the operation screen 100. As the reader, an input device 95, a one-dimensional code reader, a two-dimensional code reader, and the like are used.

Fig. 4 is a graph showing a relationship among back pressure of the screw, pressure of the molding material, and frictional resistance in the metering step according to the embodiment. Fig. 4(a) is a graph showing a relationship among back pressure of a screw, pressure of a molding material, and frictional resistance in a metering process of the injection molding machine according to the configuration 1. Fig. 4(b) is a graph showing a relationship among back pressure of the screw, pressure of the molding material, and frictional resistance in the metering process in which the measured value is corrected to the off state (canceled state) in the injection molding machine of the 2 nd configuration different from the 1 st configuration. Fig. 4(c) is a graph showing a relationship among the back pressure of the screw, the pressure of the molding material, and the frictional resistance in the metering step in which the correction value of the injection molding machine of the configuration 2 is in the on state (the execution state). In fig. 4, a case where there is a seal member for preventing leakage of the lubricant, that is, a case where the frictional resistance of the drive system of the screw 43 is large is referred to as a 1 st configuration, and a case where there is no seal member, that is, a case where the frictional resistance of the drive system of the screw 43 is small is referred to as a 2 nd configuration.

The control device 90 shown in fig. 4(a) to 4(c) includes an operation amount generating unit 97 that generates an operation amount of the controlled portion based on a set value of the control amount indicating the molding condition and a detected value of the control amount. The control device 90 shown in fig. 4(b) to (c) further includes a detected value correcting unit 98 that corrects the detected value of the controlled variable based on the difference between the configurations of the 2 nd configuration and the 1 st configuration.

Each functional block of the control device 90 illustrated in fig. 4 is a conceptual name, and is not necessarily physically configured as illustrated. All or part of each functional block may be functionally or physically distributed or combined in arbitrary units. All or any part of the processing functions performed in the functional blocks is realized by a program executed by a CPU, or may be realized as hardware based on wired logic. The same applies to the respective functional blocks of the control device shown in fig. 5.

In fig. 4(a), the structure of the injection device 40 is the 1 st structure. At this time, the operation amount generating unit 97 generates the supply current value of the injection motor 46 as the operation amount from the set value BP0 of the back pressure of the screw 43 as the control amount and the detection value BP1 thereof. The operation amount generating unit 97 generates the supply current value of the injection motor 46 so that the deviation between the set value BP0 and the detection value BP1 becomes zero. The detection value BP1 of the back pressure of the screw 43 is detected by the pressure detector 47.

In fig. 4(b), the configuration of the injection device 40 is the 2 nd configuration different from the 1 st configuration, but in the execution/cancellation selection field 103 shown in fig. 3, since cancellation (off) of the detection value correction is selected, the detection value correction unit 98 does not function, and the detection value BP2 of the back pressure of the screw 43 is not corrected. Therefore, the operation amount generating unit 97 generates the supply current value of the injection motor 46 based on the set value BP0 and the detection value BP2, as in the case where the configuration of the injection device 40 is the 1 st configuration.

However, in the measuring step, the pressure MP of the molding material is expressed by the difference (BP-FR) between the detected value BP of the back pressure of the screw 43 and the frictional resistance FR. In the metering process, the pressure MP of the molding material is required to be within an allowable range.

Here, the frictional resistance FR with respect to the pressure MP of the molding material is determined by the structure of the injection device 40 and the like. When the detected value BP of the back pressure of the screw 43 is the same, the greater the frictional resistance FR, the smaller the molding material pressure MP.

The detection value BP of the back pressure of the screw 43 related to the molding material pressure MP is determined by the supply current value of the injection motor 46 or the like. When the frictional resistance FR is the same, the larger the supply current value of the injection motor 46 is, the larger the detection value BP of the back pressure of the screw 43 becomes, and the larger the molding material pressure MP becomes.

When the detection value correcting unit 98 does not function, the supply current value of the injection motor 46 is generated in the same manner as when the configuration of the injection device 40 is the configuration 1. Therefore, the detection value BP2 of the back pressure of the screw 43 is the same as the detection value BP1 when the configuration of the injection device 40 is the 1 st configuration. On the other hand, the frictional resistance FR2 of the 2 nd structure is smaller than the frictional resistance FR1 of the 1 st structure. As a result, the pressure MP2 of the molding material of the 2 nd structure becomes greater than the pressure MP1 of the molding material of the 1 st structure.

On the other hand, in fig. 4 c, the configuration of the injection device 40 is the 2 nd configuration as in fig. 4 b, but unlike fig. 4 b, the execution/cancellation selection field 103 shown in fig. 3 selects execution (on) of detection value correction, and therefore the detection value correction unit 98 functions.

The detection value correction unit 98 corrects the detection value BP2 of the back pressure of the screw 43 based on the difference between the configurations of the 2 nd configuration and the 1 st configuration. For example, when the configuration of the injection device is changed from the 1 st configuration to the 2 nd configuration and the frictional resistance FR is reduced, the detection value correction unit 98 largely corrects the detection value BP2 of the back pressure of the screw 43. Since the corrected detection value is large, the operation amount generation unit 97 reduces the supply current value of the injection motor 46 to eliminate the deviation from the set value. Accordingly, the actual detection value BP2 'of the back pressure of the screw 43 becomes smaller, and the molding material pressure MP 2' when the injection device 40 has the configuration of the 2 nd configuration becomes the same as the molding material pressure MP1 when the injection device 40 has the configuration of the 1 st configuration. The detection value correcting unit 98 corrects the detection value BP2 of the pressure detector 47 based on the difference between the structure of the structure 2 and the structure of the structure 1 so that the pressure MP 2' of the molding material of the structure 2 becomes the same as the pressure MP1 of the molding material of the structure 1. Therefore, the injection molding machine according to the first configuration 1 and the injection molding machine according to the second configuration 2 can use the same pressure setting value in the metering step, and can ensure compatibility of settings.

In addition, the detection value BP2 'of the back pressure of the screw 43 shown in fig. 4(c) is smaller than the detection value BP2 of the back pressure of the screw 43 shown in fig. 4(b), so that the frictional resistance FR 2' shown in fig. 4(c) becomes smaller than the frictional resistance FR2 shown in fig. 4 (b). The ratio occupied by FR2 in BP2 and the ratio occupied by FR2 'in BP 2' become the same. The detection value correcting unit 98 may correct the detection value BP2 of the back pressure of the screw 43 so that the pressure MP2 ' of the molding material of the 2 nd structure becomes equal to the pressure MP1 of the molding material of the 1 st structure, based on a change (a difference between FR2 ' and FR 2) in the frictional resistance caused by a change (a difference between BP2 ' and BP 2) in the detection value of the back pressure of the screw 43.

The control in the pressure holding step is the same as the control in the metering step, and therefore, the description thereof is simplified. In the pressure maintaining step, the detection value correcting unit 98 corrects the detection value BP2 of the pressure detector 47 based on the difference between the structure of the structure 2 and the structure of the structure 1 so that the pressure MP 2' of the molding material of the structure 2 becomes the same as the pressure MP1 of the molding material of the structure 1. Thus, the injection molding machine according to the first configuration 1 and the injection molding machine according to the second configuration 2 can use the same pressure set value in the pressure holding step, and can ensure compatibility of setting. In the pressure keeping step, the detected value correcting unit 98 may correct the detected value BP2 of the pressure detector 47 based on a change in the frictional resistance (difference between FR2 ' and FR 2) caused by a change in the detected value of the pressure detector 47 (difference between BP2 ' and BP 2) so that the pressure MP2 ' of the molding material of the 2 nd structure becomes equal to the pressure MP1 of the molding material of the 1 st structure, as in the measuring step.

Fig. 5 is a diagram showing a relationship among a heating amount of a cylinder by a heater, a heat transfer amount from the cylinder to a molding material, and a moving heat amount from the cylinder to a cooler in injection molding according to an embodiment. Fig. 5(a) is a diagram showing a relationship among a heating amount of a cylinder by a heater, a heat transfer amount from the cylinder to a molding material, and a moving heat amount from the cylinder to a cooler in injection molding by the injection molding machine of the 1 st configuration. Fig. 5(b) is a diagram showing a relationship among the amount of heat of the cylinder by the heater, the amount of heat transfer from the cylinder to the molding material, and the amount of heat transfer from the cylinder to the cooler in the injection molding machine having the 2 nd configuration different from the 1 st configuration, in which the correction of the measured value is in the off state (canceled state). Fig. 5(c) is a diagram showing a relationship among the amount of heat of the cylinder by the heater, the amount of heat transfer from the cylinder to the molding material, and the amount of heat transfer from the cylinder to the cooler in the injection molding machine having the configuration 2 in which the correction of the measured value is in the on state (execution state). In fig. 5, the case where there is no heat insulating ring 41b, that is, the case where the amount of heat of movement of the cylinder 41 to the cooler 44 is large, is referred to as the 1 st configuration, and the case where there is a heat insulating ring 41b, that is, the case where the amount of heat of movement of the cylinder 41 to the cooler 44 is small, is referred to as the 2 nd configuration.

The control device 90 shown in fig. 5(a) to 5(c) includes an operation amount generating unit 97 that generates an operation amount of the controlled portion based on a set value of the control amount indicating the molding condition and a detected value of the control amount. The control device 90 shown in fig. 5(b) to (c) further includes a detected value correcting unit 98 that corrects the detected value of the controlled variable based on the difference between the configurations of the 2 nd configuration and the 1 st configuration.

In fig. 5(a), the structure of the injection device 40 is the 1 st structure. At this time, the operation amount generating unit 97 generates the supply current value of the heater 48 as the operation amount based on the set value T0 of the temperature of the cylinder 41 as the control amount and the detection value T1 thereof. The operation amount generating unit 97 generates the supply current value of the heater 48 so that the deviation between the set value T0 and the detection value T1 becomes zero. In addition, the supply current value may be represented by a ratio of an on time during which current is supplied to the heater 48 to an off time during which current is not supplied to the heater 48 (i.e., a ratio of the on time per unit time).

In fig. 5(b), the configuration of the injection device 40 is the 2 nd configuration different from the 1 st configuration, but since cancellation (closing) of the detection value correction is selected in the execution/cancellation selection field 103 shown in fig. 3, the detection value correction unit 98 does not function, and the detection value T2 of the temperature of the cylinder 41 is not corrected. Therefore, the operation amount generating unit 97 generates the supply current value of the heater 48 based on the set value T0 and the detection value T2, as in the case where the configuration of the injection device 40 is the 1 st configuration.

However, in the injection molding, the temperature of the molding material inside the cylinder 41 (hereinafter, also simply referred to as "the temperature of the molding material") is determined by the amount of heat transfer from the cylinder 41 to the molding material (hereinafter, also simply referred to as "the heating amount MH of the molding material") or the like. The heating amount MH of the molding material is represented by a difference (SH-EH) between the heating amount of the cylinder 41 by the heater 48 (hereinafter, also simply referred to as "heating amount SH of the cylinder 41") and the moving heat amount of the cylinder 41 to the cooler 44 (hereinafter, also simply referred to as "moving heat amount EH"). In injection molding, the temperature of the molding material is required to be within an allowable range.

Here, the moving heat EH related to the temperature of the molding material is determined by the structure of the injection device 40 or the like. When the heating amount SH of the cylinder 41 is the same, the smaller the moving heat EH, the larger the heating amount MH of the molding material, and the higher the temperature of the molding material.

The heating amount SH of the cylinder 41 related to the temperature of the molding material is determined by the value of the supply current of the heater 48 or the like. When the heat quantity EH is the same, the larger the current value supplied to the heater 48, the larger the heating quantity SH of the cylinder 41, and the higher the temperature of the molding material.

When the detection value correcting unit 98 does not function, the supply current value of the heater 48 is generated in the same manner as when the configuration of the injection device 40 is the configuration 1. Therefore, the heating amount SH2 of the cylinder 41 has the same value as the heating amount SH1 when the configuration of the injection device 40 is the 1 st configuration. On the other hand, the moving heat quantity EH2 of the 2 nd structure is smaller than the moving heat quantity EH1 of the 1 st structure. As a result, heating amount MH2 of the molding material of the 2 nd structure was larger than heating amount MH1 of the molding material of the 1 st structure, and the temperature of the molding material of the 2 nd structure became higher than that of the molding material of the 1 st structure.

On the other hand, in fig. 5 c, the configuration of the injection device 40 is the 2 nd configuration as in fig. 5 b, but unlike fig. 5 b, the execution/cancellation selection field 103 shown in fig. 3 selects execution (on) of detection value correction, and therefore the detection value correction unit 98 functions.

The detection value correcting unit 98 corrects the detection value T2 of the temperature of the cylinder 41 based on the difference between the configurations of the 2 nd configuration and the 1 st configuration. For example, when the injection device is changed from the 1 st configuration to the 2 nd configuration and the heat of transfer EH is small, the detection value correction unit 98 largely corrects the detection value T2 of the temperature of the cylinder 41. Since the corrected detection value is large, the operation amount generating unit 97 reduces the supply current value of the heater 48 so as to eliminate the deviation from the set value. Thus, the heating amount SH2 'of the cylinder 41 becomes smaller, the heating amount MH 2' of the molding material of the 2 nd structure and the heating amount MH1 of the molding material of the 1 st structure become the same, and the temperature of the molding material of the 2 nd structure and the temperature of the molding material of the 1 st structure become the same. The detection value correction unit 98 corrects the detection value T2 of the temperature of the cylinder 41 based on the difference between the configuration of the 2 nd configuration and the configuration of the 1 st configuration so that the temperature of the molding material of the 2 nd configuration and the temperature of the molding material of the 1 st configuration become equal to each other. Therefore, the injection molding machine according to the first configuration 1 and the injection molding machine according to the second configuration 2 can use the same temperature setting value in injection molding, and can ensure compatibility of setting.

In addition, the heating amount SH2 'of the cylinder 41 shown in fig. 5(c) is smaller than the heating amount SH2 of the cylinder 41 shown in fig. 5(b), so that the moving heat amount EH 2' shown in fig. 5(c) becomes smaller than the moving heat amount EH2 shown in fig. 5 (b). The ratio occupied by EH2 in SH2 and the ratio occupied by EH2 'in SH 2' become the same. The detection value correcting unit 98 may correct the detection value T2 of the temperature of the cylinder 41 so that the temperature of the molding material of the 2 nd structure becomes the same as the temperature of the molding material of the 1 st structure, based on the change (the difference between the EH2 'and the EH 2) of the amount of movement heat generated by the change (the difference between the SH 2' and SH 2) of the amount of heating of the cylinder 41.

While the embodiment of the injection molding machine and the like have been described above, the present invention is not limited to the above embodiment and the like, and various modifications and improvements can be made within the scope of the present invention described in the claims.

Claims (4)

1. An injection molding machine is provided with:

a control device for generating an operation amount of a part to be controlled based on a set value of a control amount indicating a molding condition and a detected value of the control amount,

the control amount and the operation amount have different relationships according to structural differences of the injection molding machine,

in the case where the operation amount in the present configuration is generated using the set value in the case where the configuration is another configuration different from the present configuration, the control device corrects the detection value based on a difference in configuration between the another configuration and the present configuration, and generates the operation amount based on the corrected detection value and the set value,

the control device stores a correction amount of the detection value for each candidate of the structure in advance, and when one candidate is selected from a plurality of candidates of the structure, the control device corrects the detection value by the correction amount corresponding to the selected structure.

2. The injection molding machine according to claim 1,

the control device associates and stores the set value with the structure.

3. The injection molding machine according to claim 1,

when the manipulated variable in the case where the configuration is the current configuration is generated using the set value in the case where the configuration is the another configuration, the control device corrects the detection value so that a predetermined physical quantity different from the control quantity is constant.

4. The injection molding machine according to claim 1,

when the operation amount of the current configuration is generated when the same mold apparatus is mounted using the set value when the configuration is the other configuration, the control device corrects the detection value when the same mold apparatus is mounted based on the configuration difference between the other configuration and the current configuration, and generates the operation amount when the same mold apparatus is mounted based on the corrected detection value and the set value.

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