JP2015123607A - Control device of injection molding machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent interference between a metal mold and a mold clamping mechanism in installing the metal mold between a fixed platen and a movable platen even if plates are added between the metal mold and the platens.SOLUTION: A maximum thickness value Mmax (=Dmax-ΣP(i)-a) of a metal mold which can be installed is determined from a sum of thicknesses ΣP(i) of plates to be added between the metal mold and platens, a metal mold thickness M, a maximum platen-to-platen distance Dmax between a fixed platen and a movable platen included in an injection molding machine, and a gap a needed for installation. If the metal mold thickness M is not larger than the maximum value Mmax, a platen-to-platen distance D (=M+ΣP(i)+a) is found and a rear platen and the movable platen are moved so that a distance between the fixed platen and the movable platen becomes the platen-to-platen distance D. If the metal mold thickness M exceeds the maximum value Mmax, an alarm is displayed. This can prevent interference between the metal mold and a mold-clamping mechanism etc. in installing the metal mold.

Description

  The present invention relates to a control device for controlling a distance between platens in accordance with a mold thickness in an injection molding machine.

  In injection molding, a movable mold and a fixed mold are attached to two platens (movable platen and fixed platen) of an injection molding machine, and molding is performed by opening and closing the mold by moving the movable platen. The mold may be fixed directly to each platen or may be attached via a plate added between the mold and the platen. The additional plate includes a heat insulating plate that prevents the mold temperature from conducting to the platen, a temperature control plate for controlling the mold temperature, and a plate for a magnetic mold clamping device for fixing the mold to the platen. There are various plates (see Patent Document 1 and Patent Document 2).

  In an injection molding machine equipped with a toggle type mold clamping mechanism, it is necessary to adjust the distance between the movable platen and the fixed platen according to the thickness of the mold carried between the movable platen and the fixed platen and the mold clamping force. When production is completed and the molds used so far are removed, and when new molds are carried in between the platens, it is desirable to shorten the loading time as much as possible in order to improve production efficiency. . For this reason, the thickness of the new mold is entered in advance, and the direction and amount of movement of the rear platen are determined from the thickness of the mold before replacement and the thickness of the new mold to be replaced. A mold thickness adjusting method for positioning is known (Patent Document 3). By using this method, before the new mold is carried between the movable platen and the fixed platen, the distance between the two platens is a distance corresponding to the thickness of the new mold, so the mold is loaded. Man-hours can be reduced.

Japanese Patent Laid-Open No. 10-286858 JP 2008-265018 A JP-A-2-307723

  When only the mold is attached between the fixed platen and the movable platen, as shown in FIG. 8, the thickness M of the attached mold 1 (fixed side mold 1a, movable side mold 1b) is set to a mold. 1 is added to the gap a necessary to carry 1 between the fixed platen 2 and the movable platen 3 to obtain a distance D between the platens necessary to carry the mold 1 in, and the distance between the platens becomes this distance D. What is necessary is just to position the movable platen 3 so that it may become.

D = M + a (1)
However, as shown in FIG. 9, when a plate as described above is added between the platens 2 and 3 and the mold 1 (in FIG. 9, between the fixed platen 2 and the fixed mold 1a, and An example in which a heat insulating plate 11 and a temperature control plate 12 are added between the movable platen 3 and the movable mold 1b is shown.), Even if the distance between the platens is the same, the thickness of the added plate Depending on the thickness of the mold that can be loaded, the thickness varies. When the movable platen is positioned without considering the thickness of the added plate and the mold is carried between the platens, the mold and the mold clamping mechanism of the injection molding machine interfere with each other and are damaged. there were.
Accordingly, the present invention provides a control device for an injection molding machine that prevents the above-described problems from occurring.

  Control of an injection molding machine that attaches one or more plates between a fixed platen and a mold, or one or both of a movable platen and a mold, and moves the movable platen back and forth by a toggle mechanism to open and close the mold In the apparatus, the invention according to claim 1 is characterized in that the input means for inputting the thickness of the plate attached between the mold and the platen and the thickness of the mold to be carried in, the total value of the thickness of the plate, and the mold An interplaten distance calculating means for determining a distance between the platens required to carry the mold between the movable platen and the fixed platen based on the thickness, and a rear platen based on the calculated interplaten distance. By moving either or both of the movable platen and the movable platen, even if various plates are added between the mold and the platen, the movable platen is moved to a position where the mold can be loaded. It is obtained to be able to-decided Mesa.

  According to a second aspect of the present invention, there is provided an input means for inputting a thickness of a plate attached between the mold and a platen and a thickness of a mold to be carried in, and a maximum platen distance between the fixed platen and the movable platen. Storage means for storing, a means for obtaining a maximum thickness of a mold that can be loaded into the injection molding machine from a total value of the plate thicknesses and a maximum distance between the platens read from the storage means, and the loading A comparison means for comparing the maximum thickness of the mold that can be compared with the thickness of the mold to be carried in, and when the thickness of the mold to be loaded exceeds the maximum thickness of the mold that can be carried in Is a warning.

  According to a third aspect of the present invention, in addition to the first aspect of the present invention, the storage means for storing the maximum distance between the platens between the fixed platen and the movable platen of the injection molding machine, the total value of the thicknesses of the plates, and the Means for obtaining the maximum thickness of a mold that can be carried between the movable platen and the fixed platen from the maximum distance between the platens read from the storage means, the maximum thickness of the mold that can be carried in, and the mold to be carried in And a means for outputting a warning when the thickness of the mold to be loaded exceeds the maximum thickness of the mold that can be loaded. When it is determined that the thickness of the mold to be carried is equal to or less than the maximum thickness of the mold that can be loaded, the distance between the platens required for loading between the movable platen and the fixed platen by the inter-platen distance calculation means Find the distance of the And so as to move both or either one of the rear platen and the movable platen was based on platen distance.

  In the invention according to claim 4, the thickness of the mold is stored in the molding condition storage device as one of the molding conditions, and is read from the molding condition storage means instead of being input from the input means. Further, in the invention according to claim 5, when the thickness of the plate used together with the thickness of the mold is stored in the molding condition storage device, this stored plate is used instead of inputting from the input means. The thickness was read out.

  According to a sixth aspect of the present invention, there is provided input means for inputting a thickness of a plate attached between the mold and the platen, storage means for storing a maximum platen distance between the fixed platen and the movable platen, Means for determining the maximum thickness of a mold that can be carried into the injection molding machine from the total thickness value and the maximum distance between the platens read from the storage means; The maximum thickness is displayed on the display device of the injection molding machine.

In the invention according to claim 7, the input means inputs the thickness for each type of plate, and in the invention according to claim 8, the input means inputs the thickness for each plate. It was supposed to be.
The invention according to claim 9 is provided with measurement means for measuring the thickness of the mold, and the input means inputs the thickness of the mold measured by the measurement means.

  Even when an additional plate is attached to the platen or mold, the distance between the platens is adjusted according to the thickness of the mold to be loaded. Interference with the mechanical part of the molding machine can be prevented. In addition, since it is possible to determine whether or not the mold can be loaded before loading the mold between the platens, it is possible to prevent a wasteful operation of erroneously loading a mold that cannot be loaded.

It is principal part explanatory drawing of one Embodiment of this invention. It is an example of the display screen for the thickness input of the metal mold | die and various plates in the embodiment. It is another example of the display screen for the thickness input of the metal mold | die and various plates in the embodiment. It is a flowchart which shows the algorithm of the platen movement process for the metal mold | die attachment in the embodiment. It is a flowchart which shows the operation | movement algorithm which displays the metal mold | die thickness which can be conveyed of another embodiment of this invention. It is an example of the display screen for input and display of plate thickness etc. in the same embodiment. It is another example of the display screen for input and display of plate thickness etc. in the same embodiment. It is explanatory drawing in the case of attaching only a metal mold | die between a stationary platen and a movable platen. It is explanatory drawing in the case of attaching a plate in addition to a metal mold | die between a fixed platen and a movable platen.

  In the present invention, the distance between the platen between the fixed platen and the movable platen necessary for carrying the mold between the platens is determined in consideration of the thickness of the plate to be added together with the mold thickness, and the obtained distance between the platens is obtained. The above-mentioned problem is solved by moving both or one of the rear platen and the movable platen so that the distance is the same. In consideration of the thickness of the additional plate, the maximum thickness of the mold that can be loaded is displayed, or the thickness of the mold to be loaded is the maximum thickness of the mold that can be loaded. The above-mentioned problem is solved by issuing a warning or an alarm when the number is exceeded.

FIG. 1 is an explanatory view of a main part of an embodiment of the present invention, and is a block diagram showing an outline of a mold clamping device and an outline of a main part of a numerical control device that controls an injection molding machine.
A fixed platen 2 is fixed on a base 7 of the injection molding machine, and a movable platen 3 and a rear platen 4 are slidably mounted on the base. A tie bar 5 is provided between the fixed platen 2 and the rear platen 4. The movable platen 3 is moved along the tie bar 5 by a toggle mechanism 6 provided between the movable platen 3 and the rear platen 4, and the fixed side mold 1 a attached to the fixed platen 2 and the movable platen 3 attached to the movable platen 3. The side mold 1b is brought into contact, and the mold is clamped. The rear platen 4 is driven by a mold thickness adjusting motor (servo motor) M2 through a transmission mechanism 9 and positioned based on the thickness of the mold 1 and the clamping force. The toggle mechanism 6 is driven by a mold opening / closing motor (servo motor) M <b> 1 through a transmission mechanism 8, moves the movable platen 3, and applies a mold clamping force to the mold 1. The mold clamping device of this injection molding machine is the same as the conventional mold clamping device.

  Reference numeral 20 denotes a numerical control device as a control device for controlling the injection molding machine in the present embodiment, and only the main part is described. The numerical control device 20 includes a CNC-CPU 28 that is a microprocessor for numerical control, a PMC-CPU 25 that is a microprocessor for a programmable machine controller, and a servo CPU 22 that is a microprocessor for servo control. By selecting mutual input / output, information can be transmitted between the microprocessors.

  The servo CPU 22 is connected to a ROM 23 that stores a control program dedicated to servo control that performs position loop, speed loop, and current loop processing, and a RAM 24 that is used for temporary storage of data. A servo amplifier 21 for driving a mold opening / closing motor M1 and a mold thickness adjusting motor M2 is connected based on a command from the CPU 22, and position / speed detectors PC1, attached to the servomotors M1, M2 are connected. The output from the PC 2 is fed back to the servo CPU 22. The servo CPU 22 drives and controls servo motors for injection and screw rotation, but is omitted in FIG.

  Connected to the PMC-CPU 25 are a ROM 26 storing a sequence program for controlling the sequence operation of the injection molding machine and a RAM 27 used for temporary storage of calculation data. The CNC-CPU 28 includes an automatic operation program for overall control of the injection molding machine, platen movement for attaching a new mold related to the present invention, display of the maximum thickness of a mold that can be loaded, A ROM 29 that stores a warning when the maximum thickness of the mold that can be carried in, a warning processing program, and the like are stored, and a RAM 30 that is used for temporary storage of calculation data and the like are connected.

  A data storage RAM 31 composed of a nonvolatile memory is a molding data storage memory for storing molding conditions and the like related to injection molding operations. In connection with the present invention, a mold and its thickness M are also stored as one of the molding conditions. Further, the maximum platen distance Dmax that the movable platen 3 opens as a mold clamping device with respect to the fixed platen 2 is set and stored in the data storage RAM 31 at the time of factory shipment of the injection molding machine.

  The display device 33 with a touch panel is connected to the bus 34 via the display control circuit 32, displays various displays and setting screens, and can perform various data input operations and the like.

  With the above configuration, the PMC-CPU 25 controls the sequence operation of the entire injection molding machine, and the CNC-CPU 28 controls the servo motors M1 and M2 based on the program stored in the ROM 29 and the data stored in the data storage RAM 31. The servo CPU 22 distributes the movement command, and the position of the servo CPU 22 based on the movement command distributed to the servo motors M1 and M2 and the position and speed feedback signals detected by the position / speed detector is the same as the conventional one. Loop control, speed loop control, and the like are performed to drive and control the servo motors M1 and M2.

  The configuration described above is the same as that of a conventional control unit for an electric injection molding machine. The only difference is that the ROM 29 moves the platen to attach a new mold, displays the maximum thickness of the mold that can be loaded, and loads A warning and alarm processing program is stored when the maximum possible mold thickness is exceeded, and the difference is that these programs are executed.

  The present invention considers the thickness of a plate such as a heat insulating plate added between the fixed platen 2 and the movable platen 3 when a new mold is mounted, and the fixed platen 2 and the movable platen for mounting the mold. The inter-plate distance D between the three plates is obtained, and the movable platen 3 or the rear platen 4 is moved so as to be the inter-plate distance D, or whether or not the mold can be loaded is determined.

  The thickness of the mold to be carried is M, and the total thickness of one or more plates added to one or both of the fixed platen 2 and the mold 1 or the movable platen 3 and the mold 1 ΣP (i), D is the distance between the platens necessary to carry the mold between the platens, and a is the value of the gap necessary for carrying in, the following equation (2) is established.

D = M + ΣP (i) + a (2)
Accordingly, if the thickness P (i) of the added plate and the thickness M of the mold 1 are input, the distance D between the platens is obtained, and the movable platen 3 and the rear platen 4 are set so as to be the distance D between the platens. One or both of them may be moved. A method of moving the movable platen 3 and the rear platen 4 based on the distance D between the platens and the clamping force applied to the mold before replacement is described in Patent Document 3 and is publicly known. This method may be used.

  As described above, the mold thickness M is normally set as one of the molding condition items when the molding conditions are set, and as the molding conditions for the mold together with other items constituting the molding conditions. Since it is stored, the mold thickness M may be read from the molding condition storage means when the mold is carried in. Further, when the mold is loaded, the thickness M of the mold to be loaded may be input and stored in the mold thickness data storage RAM 31, and the mold thickness M may be read from the data storage RAM 31. . Furthermore, a measuring instrument such as an optical distance sensor is provided outside the injection molding machine, the thickness M of the mold is measured before loading, and the measured mold thickness is input to the injection molding machine. The data may be stored in the data storage RAM 31.

  The distance D between the platens may be obtained by calculation from the positions detected by the position / speed detectors PC1 and PC2 of the mold opening / closing servomotor M1 and the mold thickness adjusting servomotor M2. Specifically, the absolute position of the rear platen detected by the position / speed detector PC2 of the mold thickness adjusting servo motor M2, and the position and toggle geometry detected by the position / speed detector PC1 of the mold opening / closing servo motor M1. It can be obtained from the relative position of the movable platen 3 with respect to the rear platen 4 obtained from the general calculation. When a general-purpose motor is used as the mold thickness adjusting motor instead of the servo motor, the absolute position of the rear platen 4 may be detected by a position sensor such as a linear scale. Further, the distance D between the fixed platen 2 and the movable platen 3 may be directly measured using an optical length measuring device. Then, the positions of the mold opening / closing servomotor M1 and the mold thickness adjusting motor M2 may be controlled so that the detected distance D between the platens becomes the distance D between the platens.

In the present embodiment, a display device 33 with a touch panel is provided, and a new mold thickness M and various plate thicknesses P (i) can be input in accordance with guides displayed on the display device. .
2 and 3 are examples of display screens for inputting the thicknesses of molds and various plates. The thickness P (i) of the various plates to be added can be input for each plate type. In the example shown in FIG.
Insulation plate thickness (die side): P (0) = 10mm
Insulation plate thickness (platen side): P (1) = 0 mm
Temperature control plate thickness: P (2) = 20 mm
Thickness of plate of magnet type mold clamping device: P (3) = 30mm
New mold thickness: M = 200mm
An example of is shown. When the temperature control plates are attached to the fixed platen side and the movable platen side, such as a temperature control plate and a magnetic mold clamping device, a value obtained by adding them is input.

  The heat insulating plate may be attached to the platen side or may be attached to the mold side. The thickness P (0) of the heat insulating plate attached to the mold side can be stored in the data storage RAM 31 of the injection molding machine as one molding condition file together with other molding conditions such as injection conditions and mold opening / closing conditions. . The mold thickness M is also stored in the data storage RAM 31 as a molding condition. Thereby, when the mold with the heat insulating plate used in the past is used again, it is not necessary to input the thickness M of the mold and the thickness of the heat insulating plate again. When the mold is called up, the thickness M of the mold and the thickness of the heat insulating plate are automatically displayed. Even if a plate other than a heat insulating plate is attached to the platen side or to the die side, the thickness of the plate attached to the die side is stored in the same way as the molding condition file to save the data of the injection molding machine. It can be stored in the RAM 31 for use. When the mold is called up, the plate thickness stored together with the mold data is also displayed.

  The example shown in FIG. 3 is a display screen in which the thickness is input for each of the various plates to be added. In this case as well, if the mold has been used in the past and the thickness of the plate attached to the mold is stored in the data storage RAM 31, the plate is automatically loaded when the mold is called. The thickness is also displayed and does not need to be entered again.

  Thus, when the mold thickness M, the thickness of the plate to be mounted between the mold and the platen are input, and the platen movement command for mounting the mold is input, the CNC-CPU 28 performs the processing shown in FIG. Start.

A total value ΣP (i) of the input plate thicknesses is calculated (step A1), and a new mold thickness M to be loaded is read (step A2). Further, the maximum platen distance Dmax that can be set by the injection molding machine is read (step A3). And the maximum value Mmax of the mold | die thickness which can be carried in is calculated.
The maximum value Mmax of the mold thickness that can be carried in is the sum of the maximum platen distance Dmax of the injection molding machine and the thickness of the additional plate according to the following equation (3) obtained by modifying the above equation (2). It calculates | requires from (SIGMA) P (i) (step A4).
Mmax = Dmax−ΣP (i) −a (3)
Next, the mold thickness M read in step A2 is compared with the maximum mold thickness Mmax that can be loaded in step A4 (step A5), and the mold thickness M can be loaded. When the mold thickness is less than the maximum value Mmax, the distance D between the platens is calculated by performing the above-described two formulas (step A6), and the distance between the fixed platen and the movable platen is calculated One or both of the rear platen 4 and the movable platen 3 are moved so that the distance D becomes (step A7), and this process ends. The rear platen is set such that the distance D between the fixed platen 2 and the movable platen 3 becomes the distance D based on the given distance D between the platens and the clamping force given to the mold before replacement. 4. The technique of moving the movable platen 3 is already known from Patent Document 3.

  If it is determined in step A5 that the mold thickness M is greater than the maximum mold thickness Mmax that can be loaded, the mold to be loaded interferes with other members such as a mold clamping device. In this case, a warning and an alarm are displayed on the display device 33 with a touch panel (step A8).

  As described above, when a new mold is carried into the injection molding machine, if the mold can be carried in, the distance between the fixed platen 2 and the movable platen 3 is the distance to which the mold is attached. If the movable platen 3 moves and the mold cannot be carried in, a warning or alarm is issued and the carrying-in operation is stopped.

FIG. 5 is a flowchart showing an operation algorithm for displaying the mold thickness that can be loaded, which is another embodiment of the present invention. In this embodiment, the mold thickness Mmax that can be loaded is displayed, and display examples on the display device 33 with a touch panel in this embodiment are shown in FIGS. In the example shown in FIG. 6, the example which inputs the thickness for every kind of plate to attach is shown, and FIG. 7 has shown the example which inputs the thickness for every plate. In this way, when the thickness of the plate to be added between the mold 1 and the fixed platen 2 or the movable platen 3 is input and the display command for the mold thickness that can be loaded is input, the CNC-CPU 28 The process shown is started. The total value ΣP (i) of the input additional plate thicknesses is calculated (step B1), and the maximum platen distance Dmax of the injection molding machine is read (step B2). Then, the maximum value Mmax of the mold thickness that can be loaded is calculated by performing the calculation of the above-described equation (3) (step B3), and the maximum value Mmax of the mold thickness that can be loaded is calculated as shown in FIG. As shown in FIG. 7, it is displayed as a mold thickness that can be carried in (step B4).
The operator uses this displayed mold thickness that can be loaded to determine whether or not the mold can be loaded. That is, the displayed mold thickness (maximum value Mmax of the mold thickness that can be loaded) is compared with the thickness of the mold to be loaded, and the thickness of the mold to be loaded If the mold is large, it is assumed that interference between the mold and other members such as the mold clamping device will occur. Only carry-in work when:

DESCRIPTION OF SYMBOLS 1 Mold 1a Fixed side mold 1b Movable side mold 2 Fixed platen 3 Movable platen 4 Rear platen 5 Tie bar 6 Toggle mechanism M1 Mold opening / closing motor M2 Mold thickness adjusting motor 20 Numerical control device

Claims (9)

Control of an injection molding machine that attaches one or more plates between a mold and a stationary platen, or one or both between a mold and a movable platen, and moves the movable platen back and forth by a toggle mechanism to open and close the mold In the device
Input means for inputting the thickness of the plate to be mounted between the mold and the platen and the thickness of the mold to be carried in;
A platen distance calculation means for obtaining a distance between the platens required to carry the mold between the movable platen and the fixed platen from the total thickness of the plates and the thickness of the mold;
The injection molding machine control apparatus is characterized in that either or both of the rear platen and the movable platen are moved based on the obtained distance between the platens. Control of an injection molding machine that attaches one or more plates between a mold and a stationary platen, or one or both between a mold and a movable platen, and moves the movable platen back and forth by a toggle mechanism to open and close the mold In the device
Input means for inputting the thickness of the plate to be mounted between the mold and the platen and the thickness of the mold to be carried in;
Storage means for storing a maximum platen distance between the fixed platen and the movable platen;
Means for determining the maximum thickness of the mold that can be carried into the injection molding machine from the total value of the plate thicknesses and the maximum distance between the platens read from the storage means;
A comparison means for comparing the maximum thickness of the mold that can be loaded with the thickness of the mold to be loaded;
And a warning is output when the thickness of the mold to be carried exceeds the maximum thickness of the mold that can be carried in. Storage means for storing a maximum platen distance between a fixed platen and a movable platen of an injection molding machine;
Means for obtaining the maximum thickness of the mold that can be carried between the movable platen and the fixed platen from the total value of the plate thicknesses and the maximum distance between the platens read from the storage means;
A comparison means for comparing the maximum thickness of the mold that can be loaded with the thickness of the mold to be loaded;
Means for outputting a warning when the thickness of the mold to be loaded exceeds the maximum thickness of the mold that can be loaded;
And when the thickness of the mold to be carried in by the comparison means is determined to be equal to or less than the maximum thickness of the mold that can be carried in, the distance calculation means between the platens is set between the movable platen and the fixed platen. 2. The injection according to claim 1, wherein a distance between the platens necessary for carrying in is obtained, and both or one of the rear platen and the movable platen are moved based on the obtained distance between the platens. Control device for molding machine.   The thickness of the mold is stored in a molding condition storage device as one of molding conditions, and is read from the molding condition storage means instead of being input from the input means. The control apparatus of the injection molding machine as described in any one of Claims.   When the thickness of the plate used together with the thickness of the mold is stored in the molding condition storage device, the stored thickness of the plate is read instead of inputting from the input means. 5. The control device for an injection molding machine according to claim 4. Control of an injection molding machine that attaches one or more plates between a mold and a stationary platen, or one or both between a mold and a movable platen, and moves the movable platen back and forth by a toggle mechanism to open and close the mold In the device
Input means for inputting the thickness of a plate to be attached between the mold and the platen;
Storage means for storing a maximum platen distance between the fixed platen and the movable platen;
Means for obtaining the maximum thickness of the mold that can be carried into the injection molding machine from the total value of the plate thicknesses and the maximum distance between the platens read from the storage means;
And a control device for the injection molding machine, wherein the determined maximum thickness of the mold is displayed on the display device of the injection molding machine.   The control device for an injection molding machine according to claim 1, wherein the input means inputs a thickness for each type of the plate.   The control device for an injection molding machine according to claim 1, wherein the input unit inputs a thickness of each plate.   6. The injection molding machine according to claim 1, further comprising a measuring unit that measures a thickness of the mold, wherein the input unit inputs a thickness of the mold measured by the measuring unit. Control device.