Control device of injection molding machine, injection molding machine, injection molding system and control method of injection molding machine

Abstract

The present invention provides a control device for an injection molding machine, an injection molding machine, an injection molding system, and a control method for an injection molding machine, which can effectively reduce the risk of damage to a mold device. The control device of the present invention is used for an injection molding machine (1), and has a control unit. A mold device (101) installed on the injection molding machine (1) has a movable protrusion (104) that can move forward and backward relative to an internal space (Si) of the mold device (101) and protrude into the internal space (Si) by moving forward. The injection molding machine (1) has a protrusion drive device (41) that drives the movable protrusion (104) of the mold device (101). The protrusion drive device (41) is controlled by the control unit so as to limit the protrusion amount of the movable protrusion (104) of the mold device (101) into the internal space (Si) based on an allowable set value.

Description

Technical Field

[0001] The present invention relates to a control device for an injection molding machine having a protrusion driving device for driving a movable protrusion of a mold device, an injection molding machine, an injection molding system, and a control method for an injection molding machine. Background Art

[0002] As such an injection molding machine, there is an injection molding machine described in Patent Document 1, for example.

[0003] Patent document 1 discloses "an injection molding machine, comprising a clamping device including a pressing plate for mounting a mold, and an ejector device for ejecting a molded product from the mold, the ejector device having an ejector rod, an ejector crosshead connected to the ejector rod, and a drive mechanism for advancing and retracting the ejector crosshead, the pressing plate having an opening portion for implementing an operation of connecting the ejector rod to the ejector crosshead, the internal space of the pressing plate being accessible from the external space of the pressing plate via the opening portion, and being accessible in a direction orthogonal to the mold opening and closing direction, the injection molding machine having a switching cover, the switching cover being switchable between a first state for allowing the access from the external space to the internal space via the opening portion, and a second state for suppressing the scattering of lubricant from the internal space to the external space via the opening portion".

[0004] Patent document 1 states that "The movable mold portion 840 is freely movable inside the fixed mold portion 830. The movable mold portion 840 includes, for example, a plate-shaped ejector plate 841 perpendicular to the mold opening and closing direction, and a rod-shaped ejector pin 844 extending forward from the ejector plate 841." and "The ejector device 200 performs an ejection process under the control of the control device 700. In the ejection process, the movable mold portion 840 is advanced by advancing the ejector rod 210 from the standby position to the ejection position at a set moving speed, thereby ejecting the molded product."

[0005] Patent Document 1: Japanese Patent Application Publication No. 2020-108926

[0006] In an injection molding machine equipped with a mold device having a movable protruding portion such as the above-mentioned “ejector pin”, a protrusion driving device such as an “ejector device” for driving the movable protruding portion is provided.

[0007] In such an injection molding machine, for example, due to an incorrect setting of the injection molding operation by the user, when the mold device is in the mold-closing state, if the protrusion driving device is driven to cause the movable protrusion to protrude toward the inner space of the mold device, the movable protrusion may collide with the inner surface of the mold device, which may damage the mold device.

[0008] In particular, when performing clamping compression of the molding material between the fixed mold and the movable mold of the mold device based on the clamping device, or protrusion compression of the molding material at the movable protrusion of the protrusion driving device, the risk of damage to the mold device caused by the action of the movable protrusion may be significant. Summary of the invention

[0009] The present invention aims to solve such a problem, and an object of the present invention is to provide a control device for an injection molding machine, an injection molding machine, an injection molding system, and a control method for an injection molding machine, which can effectively reduce the risk of damage to a mold device.

[0010] A control device capable of solving the above-mentioned problems is used for an injection molding machine, and comprises a control unit, wherein a mold device installed on the above-mentioned injection molding machine has a movable protrusion, and the movable protrusion can be displaced forward and backward relative to the internal space of the mold device, and protrudes into the internal space by forward displacement. The above-mentioned injection molding machine is equipped with a protrusion driving device, and the protrusion driving device drives the above-mentioned movable protrusion of the mold device. The protrusion driving device is controlled by the above-mentioned control unit so as to limit the protrusion amount of the above-mentioned movable protrusion of the mold device into the above-mentioned internal space based on the allowable set value.

[0011] The injection molding machine includes the above-mentioned control device and the above-mentioned protrusion driving device.

[0012] The injection molding system includes the above-mentioned injection molding machine and a mold device attached to the above-mentioned injection molding machine.

[0013] A control method for an injection molding machine capable of solving the above-mentioned problems, wherein a mold device installed on the above-mentioned injection molding machine has a movable protrusion, which can be displaced forward and backward relative to the internal space of the mold device and protrude into the internal space by forward displacement. The above-mentioned injection molding machine is equipped with a protrusion driving device, which drives the above-mentioned movable protrusion of the mold device. The control method of the above-mentioned injection molding machine includes: controlling the protrusion driving device so as to limit the protrusion amount of the above-mentioned movable protrusion of the mold device into the above-mentioned internal space based on an allowable set value.

[0014] Effects of the Invention

[0015] According to the control device and the control method of the injection molding machine, the risk of damage to the mold device can be effectively reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a cross-sectional view showing an injection molding machine to which the control device according to one embodiment of the present invention can be applied, together with a mold device attached to the injection molding machine.

[0017] Figure 2This is a block diagram showing a control device according to one embodiment of the present invention.

[0018] Figure 3 It means using Figure 1 An enlarged cross-sectional view of a mold device and main parts of the injection molding machine, which is an example of an injection molding operation of the injection molding machine.

[0019] Figure 4 It means next Figure 3 A cross-sectional view of the action.

[0020] Figure 5 It means next Figure 4 A cross-sectional view of the action.

[0021] Figure 6 It means next Figure 5 A cross-sectional view of the action.

[0022] Figure 7 It means next Figure 6 A cross-sectional view of the action.

[0023] Figure 8 It means next Figure 7 A cross-sectional view of the action.

[0024] Fig. 9 It means being able to Figure 2 FIG. 1 is a diagram showing a portion of a setting screen displayed on a display unit of a control device.

[0025] Fig.10 It means being able to Figure 2 A cross-sectional view showing an example of dimensions of a mold device included in mold information input to an input unit of a control device.

[0026] Fig.11 It means being able to Figure 2 A cross-sectional view of another example of the dimensions of a mold device included in the mold information input to the input unit of the control device.

[0027] Explanation of symbols:

[0028] 1: injection molding machine; 2: base frame; 11: injection device; 12: cylinder; 12a: supply port; 12b: nozzle; 12c: water-cooled cylinder; 13: screw; 14: heater; 15: motor box; 21: moving device; 22: hydraulic pump; 23: pump working motor; 24: hydraulic cylinder; 25: sliding base; 26: guide; 31: mold clamping device; 32: pressing plate; 32a: fixed pressing plate; 32b: movable pressing plate; 32c: connecting rod; 32d: guide component; 33: pressing plate running mechanism; 34: rear pressing plate; 35: mold clamping motor; 36: motion conversion mechanism; 36a: screw shaft; 36b: nut; 37: toggle mechanism; 37a~37c: connecting rod; 37d: crosshead; 38: mold thickness adjustment motor; 41: protrusion drive moving device; 42: protruding rod; 43: protruding driving source; 101: mold device; 102: fixed mold; 103: movable mold; 104: movable protrusion; 105a: protruding plate; 105b: rod abutment component; 106: movable side mounting plate; 107: spacer block; 108: receiving plate; 108a: elastic component; 109: movable side template; 109a: material pressing component; 109b: pressurizing component; 109c: gate; 110: fixed side mounting plate; 111: fixed side template; 112: runner sleeve; 112a: runner; 121: interval measuring device; 122: displacement sensor; 123: target; 201: display part of the display unit; D1, D2: separation distance; Mm: molding material; Se: space; Si: internal space. DETAILED DESCRIPTION

[0029] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0030] A control device according to an embodiment of the present invention can be used, for example, Figure 1 An injection molding machine 1 is shown. Figure 1 The injection molding machine 1 generally comprises: an injection device 11, which melts a molding material such as a thermoplastic resin and injects it into a mold device 101 by rotating and advancing a screw 13 arranged inside and heating by a heater 14 arranged around it; a moving device 21, which moves the injection device 11 forward or backward relative to the mold device 101; a clamping device 31, which moves the mold device 101 between an open mold state and a clamping mold state to open and close; and a protrusion driving device 41, which drives a movable protrusion 104 of the mold device 101.

[0031] (Protruding drive device)

[0032] The protrusion drive device 41 drives the movable protrusion 104 of the mold device 101. In addition to the movable protrusion 104, the mold device 101 sometimes has a fixed mold 102 and a movable mold 103, which are respectively mounted on the fixed platen 32a and the movable platen 32b of the mold clamping device 31. In the mold clamping state of the mold device 101, an internal space Si including a cavity is divided inside. The mold device 101 is appropriately mounted on the injection molding machine 1 according to the shape of the molded product to be manufactured, and can be replaced, and is not considered as a part of the injection molding machine 1. In addition, here, a device including the injection molding machine 1 and the mold device 101 mounted on the injection molding machine 1 is referred to as an injection molding system.

[0033] Here, if Figure 3 As shown, the movable protrusion 104 of the mold device 101 is located inside the movable mold 103, for example, on the movable mold 103 side, and is in the shape of a pin or a rod extending through at least a portion of the movable mold 103. In this example, three pin-shaped movable protrusions 104 are provided, but the number, size and shape of the movable protrusions can be appropriately changed. There are also mold devices having one, two, or four or more movable protrusions.

[0034] Inside the movable mold 103, the movable protrusion 104 is arranged to be able to move forward and backward relative to the internal space Si of the mold device 101, and is disposed on the side toward the fixed mold 102 ( Figure 3 On the other hand, when the movable protrusion 104 moves toward the movable platen 32b side ( Figure 3 When the displacement is backward, such as Figure 3 As shown, the front end of the movable protrusion 104 is located on the inner side of the movable platen 32b side relative to the internal space Si. In addition, the movable die 103 has two or other appropriate number of protrusion plates 105a that connect and overlap the three movable protrusions 104, and a rod contact member 105b such as a rod that is fixed or detachably provided on the back of the protrusion plate 105a in an upright state. The protrusion rod 42 described later of the protrusion drive device 41 contacts the rod contact member 105b, and the protrusion plate 105a moves forward and backward together with the movable protrusion 104.

[0035] Here, the protrusion drive device 41 shown in the figure includes: a protrusion rod 42 extending into the interior of the movable platen 32b, abutting against the rod abutment member 105b of the movable die 103 to move the movable protrusion 104 forward and backward; and a protrusion drive source 43 including a motion conversion mechanism such as a protrusion motor and a ball screw that moves the protrusion rod 42. The movable protrusion 104 is moved forward and backward by the protrusion drive device 41.

[0036] The movable protrusion 104 and the protrusion driving device 41 are mainly used to remove the molded product formed by the molding material injected from the injection device 11 into the internal space Si of the mold device 101 and solidified. When removing the molded product from the mold device 101, the mold device 101 is made Figure 3 In the mold open state shown, the movable protrusion 104 is protruded and displaced toward the internal space Si by the protrusion driving device 41, and the molded product is pushed out from the mold device 101 by the movable protrusion 104. The movable protrusion 104 is sometimes called an ejector pin, and the protrusion driving device 41 is also called an ejector device.

[0037] (Control device and control method)

[0038] like Figure 2 As shown, the control device for the injection molding machine 1 has at least a control unit for controlling the operation of the protrusion drive device 41. The control unit may be dedicated to the protrusion drive device 41, but in most cases, it can control not only the protrusion drive device 41 but also the operation of other devices of the injection molding machine 1 such as the injection device 11, the moving device 21, and the mold clamping device 31. In addition to being connected to a protrusion drive source such as a protrusion motor of the protrusion drive device 41 of the injection molding machine 1, the control unit can also be connected to various other drive sources such as a measuring motor, an injection motor, and a mold clamping motor, and various sensors such as temperature and rotation speed.

[0039] As in the embodiment shown in the figure, the control device sometimes also has an input unit for the user of the injection molding machine 1 to input information, and / or a display unit for transmitting information to the user. The input unit and / or the display unit are respectively connected to the control unit. In the control device having the input unit and the display unit, at least a part of them can also be set as a touch panel. The control device sometimes includes a storage unit connected to the control unit and storing information or data. The injection molding machine 1 sometimes has such a control device.

[0040] In the above-mentioned protrusion drive device 41 and mold device 101, if the user does not correctly set the injection molding action, when the mold device 101 is in the mold-closing state, the movable protrusion 104 may be driven by the protrusion drive device 41 to protrude greatly toward the internal space Si of the mold device 101. In this case, the front end of the movable protrusion 104 that moves forward toward the fixed mold 102 side collides with the inner surface of the mold device 101, more specifically, the inner surface of the fixed mold 102 that divides the internal space Si, and there is a possibility that the mold device 101 is damaged at the front end and the like.

[0041] In order to cope with this situation, the control device of this embodiment controls the protrusion drive device 41 through the control unit so as to limit the protrusion amount of the movable protrusion 104 of the mold device 101 into the internal space Si based on a predetermined allowable setting value. The allowable setting value is, for example, sometimes set to the protrusion amount of the movable protrusion 104 when the front end of the movable protrusion 104 contacts the inner surface of the fixed mold 102, and is set in advance before the injection molding operation is performed. In this case, the control device can control the protrusion drive device 41 so that the protrusion amount of the movable protrusion 104 into the internal space Si does not exceed the allowable setting value.

[0042] By performing such control, it is possible to avoid the movable protrusion 104 from colliding with the inner surface of the mold device 101 when the mold device 101 is brought into the mold-closed state, and thus it is possible to effectively suppress damage to the mold device 101.

[0043] However, the mold device 101 shown in the figure is configured so as to be able to perform mold clamping and compression of the molding material between the fixed mold 102 and the movable mold 103 by the mold clamping device 31 .

[0044] In more detail, in the mold device 101 as an example, the movable mold 103 is provided with a movable side mounting plate 106 mounted on the movable pressing plate 32b, a spacer block 107 which divides the space Se on the inner side in which the above-mentioned protruding plate 105a is arranged, a receiving plate 108 provided with an elastic component 108a, and a movable side template 109 opposite to the fixed mold 102 in sequence from the movable pressing plate 32b side toward the fixed mold 102 side.

[0045] The movable side mold plate 109 of the movable mold 103 is fixedly mounted on the surface of the receiving plate 108 on the fixed mold 102 side, and is divided into a plurality of parts including a material pressing part 109a that compresses and presses the molding material by mold clamping, and a pressurizing part 109b that is supported on the receiving plate 108 via an elastic part 108a and presses the fixed mold 102 when the mold clamping force is applied. Figure 3 In the case shown in FIG. 1 , in the direction in which the movable platen 32b approaches the fixed platen 32a ( Figure 3 The left-right direction is also called the "moving direction of the movable platen". Figure 3 In the up-down direction), two material pressing components 109a and three pressing components 109b in block shape are alternately arranged.

[0046] Through holes extending from the space Se of the protruding plate 105a to the internal space Si are formed on the receiving plate 108 and a total of three material pressing parts 109a and a pressurizing part 109b located on the inner side in a direction perpendicular to the moving direction of the movable pressing plate, and the above-mentioned multiple movable protrusions 104 are inserted and arranged on the inner side of each of these through holes.

[0047] In addition, the elastic member 108a provided on the receiving plate 108 can be set as a spring member such as a coil spring that overcomes the mold clamping force acting in the moving direction of the movable platen, or although not shown in the figure, it can also be set as a cylinder body that moves the pressurizing member 109b in the same direction.

[0048] The fixed mold 102 shown in the figure includes a fixed side mounting plate 110 mounted on the fixed platen 32a and a fixed side mold plate 111 provided on the surface of the fixed side mounting plate 110 on the movable mold 103 side. A runner bushing 112 is provided in the substantially central area of ​​the fixed side mounting plate 110 and the fixed side mold plate 111. A runner 112a is formed inside the runner bushing 112 to guide the molding material Mm injected from the injection device 11 to the internal space Si.

[0049] The mold device 101 can be provided with a gap measuring device 121 for grasping the gap between the material pressing member 109a and the fixed side mold plate 111 in the moving direction of the movable platen. Here, the gap measuring device 121 includes a non-contact displacement sensor 122 installed around the receiving plate 108, and a target 123 installed around the movable side mold plate 109 at a position opposite to the displacement sensor 122. However, in addition to being able to replace the installation positions of the displacement sensor and the target, it is also possible to install one of them on the spacer block 107 instead of the receiving plate 108, and the other on the fixed side mold plate 111 instead of the movable side mold plate 109. In addition, a gap measuring device including a contact displacement sensor can also be used.

[0050] When the mold device 101 described above is mounted on the injection molding machine 1 , the control unit of the control device can execute mold clamping and compression of the molding material Mm, for example, as described below.

[0051] First, in Figure 3 In the mold device 101 in the mold opening state shown in FIG. 1 , the movable mold 103 is moved relative to the fixed mold 102 by using the mold clamping device 31, so that the mold device 101 is as shown in FIG. Figure 4 At this time, the pressurizing member 109b of the movable mold 103 contacts the fixed side mold plate 111 of the fixed mold 102, but almost no clamping force is applied to the mold device 101, and the elastic member 108a between the pressurizing member 109b and the receiving plate 108 is substantially not compressed.

[0052] Then, if Figure 5As shown, the movable mold 103 is further displaced relative to the fixed mold 102 by the mold clamping device 31, the elastic member 108a is compressed, and the pressurizing member 109b is pressed against the fixed side mold plate 111. Thus, a cavity is divided in the internal space Si of the mold device 101. Here, the pressurizing member 109b is pressed against the fixed side mold plate 111 with a predetermined mold clamping force by the restoring force of the compressed elastic member 108a. Thus, between the pressurizing member 109b and the fixed side mold plate 111, as described later, it is possible to suppress the generation of burrs in the molded product after the molding material Mm is filled into the cavity.

[0053] Then, the molding material Mm accumulated in the front end of the cylinder 12 of the injection device 11 is injected from the nozzle 12b. Figure 6 As shown, the molding material Mm injected from the injection device 11 reaches the internal space Si of the mold device 101 through the runner 112a on the inner side of the runner bushing 112, and fills the internal space Si. In addition, in this example, the central pressurizing member 109b of the movable side template 109 of the movable mold 103, which is supported by the elastic member 108a and is opposite to the runner 112a, is formed in a shape whose opposing surface is recessed toward the movable pressing plate 32b side than the boundary between the other pressurizing members 109b and the fixed side template 111, that is, the parting line. The empty space between the central pressurizing member 109b and the fixed side template 111 in the internal space Si functions as a flow channel. A gate 109c (refer to FIG. 1 ) is formed between the central pressurizing member 109b and each material pressing member 109a adjacent to it on both sides, so that the molding material Mm flows into the cavity of the internal space Si on the material pressing member 109a side. Figure 5 ).

[0054] After the internal space Si of the mold device 101 is filled with a certain amount of molding material Mm, as a mold clamping compression, as shown in FIG. Figure 7 As shown, the elastic member 108a is further compressed by the mold clamping device 31 and the movable mold 103 is further displaced toward the fixed mold 102, thereby compressing the molding material Mm in the internal space Si between the fixed mold 102 and the movable mold 103. When the mold clamping compression is performed, even in the case of molding a relatively thin molded product, since the molding material Mm is fully distributed throughout the entire cavity of the internal space Si, the occurrence of poor molding such as shrinkage cavities can be effectively prevented. During the mold clamping compression, the interval between the material pressing member 109a and the fixed side mold plate 111 and the compression amount of the elastic member 108a can be adjusted based on the measurement value of the above-mentioned interval measuring device 121.

[0055] Furthermore, the control unit can perform protrusion compression in which the molding material Mm is compressed by the movable protrusion 104 using the protrusion driving device 41 in addition to or without performing the mold clamping compression described above.

[0056] In the case of performing both mold clamping compression and protruding compression, before filling the molding material Mm into the internal space Si of the mold device 101, as shown in FIG. Figure 5 As shown, the movable protrusion 104 of the mold device 101 is moved backward in advance by the protrusion driving device 41, and the front end of the movable protrusion 104 is arranged at a position deeper than the internal space Si in the through hole.

[0057] In this state, if Figure 6 As shown, when the molding material Mm is injected from the injection device 11 and filled into the internal space of the mold device 101, the molding material Mm also enters the gap to the front end in the through hole into which the movable protrusion 104 is inserted. Figure 7 Mould compression shown.

[0058] During or after the mold closing compression, as the protrusion compression, the movable protrusion 104 is driven by the protrusion driving device 41, as shown in FIG. Figure 8 As shown, for example, the movable protrusion 104 is moved forward to a position close to the front end of the movable protrusion 104 protruding toward the internal space Si. As a result, the molding material Mm entering the through hole into which the movable protrusion 104 is inserted is pushed toward the internal space Si by the movable protrusion 104 that has moved forward, and the molding material Mm in the internal space Si is compressed.

[0059] After that, the molding material Mm is cooled in the internal space Si to harden it, and the molded product is formed. After the molded product is formed in the internal space Si, the control unit, although not shown in the figure, can make the mold device 101 open, and make the protrusion drive device 41 move the movable protrusion 104 forward and protrude into the internal space Si, and take out the molded product from the internal space Si.

[0060] When performing mold clamping compression and protrusion compression as described above, if the user incorrectly sets the action of the protrusion drive device 41, the problem of damage to the mold device 101 becomes obvious. That is, before or during the mold clamping compression, the movable protrusion 104 protrudes greatly into the internal space Si, and when its front end abuts against the inner surface of the fixed mold 102, a large mold clamping force is applied to the movable protrusion 104 by the mold clamping compression. As a result, the risk of damage to the mold device 101 such as bending of the movable protrusion 104 increases. Therefore, this embodiment is particularly advantageous because it can reduce the above-mentioned risk of damage to the mold device 101 when the mold clamping compression and protrusion compression are performed by the control unit of the control device.

[0061] In order to effectively reduce such a risk of damage, it is preferred that the control unit prohibits the user from executing the above-mentioned protrusion compression when the allowable setting value for limiting the protrusion amount of the movable protrusion 104 is not set. For example, when the allowable setting value is not set, the control unit can prevent the user from selecting the execution of the protrusion compression through the input unit, or even if the execution is selected, the injection molding operation including the protrusion compression is not started. In addition, the control unit can also make the user aware that the allowable setting value is not set by displaying it on the display unit, giving an alarm, etc.

[0062] When performing protrusion compression, the user can input the protrusion amount of one stage or multiple stages when the movable protrusion part 104 is moved forward by the protrusion driving device 41 during protrusion compression into the input unit for setting. Fig. 9 , as an example, a display portion 201 related to the protrusion amount of the movable protrusion 104 in a setting screen that the control unit can display on the display unit is shown. In this example, when performing protrusion compression, the protrusion amount of the movable protrusion 104 can be set in four stages from the first to the fourth.

[0063] Here, when the user intends to input a protrusion amount limited by an allowable set value, such as a protrusion amount exceeding the allowable set value, from the input unit as the protrusion amount of the movable protrusion 104 in at least one of the first to fourth stages, the control unit preferably prohibits the execution of protrusion compression. In addition, the control unit may also prohibit the user from inputting a protrusion amount limited by an allowable set value to the input unit. This is because when the operation of the protrusion drive device 41 such as protrusion compression is performed with such a protrusion amount, the risk of damage to the mold device 101 increases. As needed, for example, using a display unit, a hint of the meaning of prohibiting the execution of protrusion compression and a hint of the meaning of prohibiting the input of the protrusion amount limited by the allowable set value are provided to the user.

[0064] The preset allowable setting value is preferably as follows Fig. 9 The user can thereby easily recognize that the allowable setting value is set, thereby enabling protrusion compression to be performed, and that the allowable setting value is the upper limit value of the protrusion amount in each stage that can be input.

[0065] The permissible setting value can be set by the user's decision and input from the input unit. In this case, the protrusion drive device 41 can be controlled based on the permissible setting value set by the user.

[0066] Preferably, in addition to or instead of the user being able to input the allowable setting value, the user is able to input mold information related to the mold device into the input unit, and the control unit determines the allowable setting value based on the mold information input by the user.

[0067] The mold information may include information about the size of the mold device 101. Specifically, as the mold information, for example, Fig.10 As shown in FIG. 1 , in the moving direction of the movable platen, there is a separation distance D1 between the inner surface of the fixed mold 102 and the inner surface of the movable mold at the protruding position of the movable protrusion 104 in a state where the movable mold 103 is pressed to the fixed mold 102 to the maximum extent. The separation distance D1 is the maximum protrusion amount of the movable protrusion 104 that can protrude toward the internal space Si in the mold clamping state, and the control unit sometimes sets it to an allowable setting value.

[0068] like Fig.11 As shown in FIG. 1 , the mold information sometimes includes a separation distance D2 between the rod contact member 105b of the mold device 101 and the front end of the protruding rod 42 when the protruding rod 42 of the protruding driving device 41 is moved back to the maximum extent in the moving direction of the movable platen. The value obtained by adding the separation distances D1 and D2 becomes the allowable setting value of the stroke amount of the protruding rod 42, and the control unit can also control the protruding driving device 41 based on such an allowable setting value of the stroke amount. In addition, the above-mentioned Fig. 9 The “limit position” is set to the permissible setting value of the stroke of the protruding rod 42 (the stroke from the maximum retracted position of the front end of the protruding rod 42 to the permissible maximum forward position).

[0069] Furthermore, the control unit determines the allowable setting value for the mold device 101 mounted on the injection molding machine 1. Therefore, for example, in the mold device 101 in the mold-clamped state, the movable protrusion 104 can be displaced forward by the protrusion driving device 41 to protrude into the internal space Si. When the movable protrusion 104 stops by contacting the inner surface of the mold device 101 due to the forward displacement, the control unit can determine the allowable setting value according to the forward stop position of the movable protrusion 104.

[0070] Here, since the movable protrusion 104 is displaced forward for the purpose of determining the allowable setting value, it is not necessary to fill the molding material into the internal space Si of the mold device 101. When the mold device 101 is replaced with a different one from the past, the control unit can determine the allowable setting value based on the forward displacement of the movable protrusion 104 before performing the injection molding operation. In addition, it is preferable to drive the forward displacement of the movable protrusion 104 with a relatively low torque by the protrusion driving device 41 to avoid damage or destruction of the mold device 101.

[0071] (Mold clamping device)

[0072] The mold clamping device 31 opens and closes the mold device 101 by moving the movable mold 103 toward or away from the fixed mold 102 of the mold device 101, so that the mold device 101 is in a mold clamping state, a mold closed state, or a mold open state. The mold clamping device 31 includes a platen 32 including a fixed platen 32a and a movable platen 32b, and a platen operating mechanism 33 for operating the platen 32.

[0073] The fixed platen 32a of the platen 32 is fixedly mounted on the base frame 2. On the other hand, the movable platen 32b is arranged on a guide member 32d laid on the base frame 2, and can slide in a direction of separation and a direction of approach relative to the fixed platen 32a. The mold clamping device 31 is provided with one or more connecting rods 32c extending from the fixed platen 32a toward the rear platen 34 side described later and connecting the fixed platen 32a and the rear platen 34. In this example, the movable platen 32b is guided by the connecting rod 32c to separate and approach relative to the fixed platen 32a, but it may not be guided by the connecting rod 32c.

[0074] The pressure plate operating mechanism 33 includes a rear pressure plate 34 arranged on the base frame 2, a mold clamping motor 35 arranged on the rear pressure plate 34, a motion conversion mechanism 36 that converts the rotational motion of the mold clamping motor 35 into a linear motion in the moving direction of the movable pressure plate, and a toggle mechanism 37 that increases the force transmitted to the motion conversion mechanism 36 and transmits it to the movable pressure plate 32b.

[0075] The motion conversion mechanism 36 may be any mechanism capable of converting rotational motion into linear motion, and in this example, is composed of a screw shaft 36a driven to rotate by the mold clamping motor 35 and a nut 36b screwed with the screw shaft 36a. The motion conversion mechanism 36 may also be a ball screw.

[0076] The toggle mechanism 37 for increasing the transmission force from the motion conversion mechanism 36 is formed by swingably connecting a plurality of links 37a to 37c that connect the rear pressure plate 34 and the nut 36b to the movable pressure plate 32b via a joint.

[0077] The number and shape of the connecting rods and joints can be changed appropriately, but Figure 1 In the illustrated case, a pair of link groups consisting of link rods 37a to 37c located above and below with a cross head 37d interposed therebetween are swingably connected to the cross head 37d connected to the nut 36b and extending in the vertical direction.

[0078] In addition, in addition to the above-mentioned mold clamping motor 35, a mold thickness adjustment motor 38 can be provided on the rear platen 34. The mold thickness adjustment motor 38 has the following function: by applying a rotational driving force to the screw shaft and the nut connected to the extension of each connecting rod 32c of the above-mentioned platen 32, the gap between the fixed platen 32a and the rear platen 34 movably mounted on the base frame 2 is adjusted. Thus, even when the mold device 101 is replaced or the thickness of the mold device 101 is changed due to temperature changes, the mold thickness can be adjusted so that the desired mold clamping force can be applied to the mold device 101. Although not shown in the figure, the mold thickness can be adjusted even if the fixed platen side is movable on the base frame 2 and the rear platen side is fixed.

[0079] The mold clamping device 31 shown in the figure is a horizontal type in which the moving direction of the movable platen 32b is parallel to the horizontal direction, but may be a vertical type in which the moving direction is a vertical direction.

[0080] (Injection device)

[0081] The injection device 11 mainly includes: a cylinder 12 of a cylindrical shape or the like, extending toward the mold device 101; a screw 13, which is arranged inside the cylinder 12 with its central axis parallel to the central axis of the cylinder 12 and has a spiral thread around it; a heater 14 of a belt shape or the like, which is arranged on the outer peripheral side of the cylinder 12 so as to surround the periphery of the cylinder 12; and a motor box 15, which is arranged on the rear side of the cylinder 12 and the screw 13. Although not shown in the figure, a measuring motor for rotating the screw 13 around the central axis in order to accumulate a predetermined amount of molding material at the front end of the cylinder 12, an injection motor for moving the screw 13 forward and backward in each direction of approaching the mold device 101 and moving away from the mold device 101, and a pressure detection sensor for detecting the pressure applied to the screw 13 by the molding material are arranged in the motor box 15.

[0082] Here, the direction of the fixed platen 32a of the mold clamping device 31 close to the fixed mold 102 of the mold installation device 101 is set as the front side, and the direction away from the fixed platen 32a is set as the rear side. Figure 1 In the figure, when the injection device 11 located on the right side of the fixed platen 32a is viewed, the left side close to the fixed platen 32a is the front side, and the right side away from the fixed platen 32a is the rear side.

[0083] The cylinder 12 is provided with a supply port 12a at the rear side in front of the motor box 15, and a hopper for feeding molding material into the cylinder 12 can be installed at the supply port 12a. In addition, a nozzle 12b with a smaller cross-sectional area is provided at the front side of the front end of the cylinder 12 close to the mold device 101. In addition, a water-cooled cylinder 12c based on water cooling or the like can be provided near the supply port 12a.

[0084] The heater 14 disposed around the cylinder 12 surrounding the nozzle 12b is divided into a plurality of parts in the cylinder axial direction as shown in the figure, and can heat the inside of the cylinder 12 inside each heater part at a different temperature. A temperature detector can be provided in each heater part.

[0085] Although not shown in the figure, a backflow prevention ring is sometimes arranged around the diameter reduction portion provided by partially reducing the outer diameter of the screw 13 at the front end side of the screw 13 to prevent the molding material that is transported to the front side than the screw 13 from flowing back toward the rear side due to the forward and backward displacement together with the screw 13. The backflow prevention ring is displaced forward and backward relative to the screw 13 according to the pressure received from the molding material located on the front side or the rear side than the screw 13, thereby allowing only the molding material to flow from the rear side to the front side.

[0086] According to the injection device 11 having such a structure, the molding material introduced into the cylinder 12 from the supply port 12a is melted by the rotation of the screw 13 driven by the measuring motor under the heating of the heater 14 on the outer peripheral side of the cylinder 12 in the measuring process, and is transported toward the front side in the cylinder 12 and accumulated at the front end of the cylinder 12. At this time, the screw 13 is displaced backward by the injection motor, and a space for accumulating the molding material is formed at the front end of the cylinder 12.

[0087] Then, in the filling process, the molding material at the front end of the cylinder 12 is injected toward the mold device 101 through the nozzle 12b by moving the screw 13 forward. Furthermore, in the subsequent pressure holding process, the molding material remaining at the front end of the cylinder 12 exerts pressure on the molding material filled in the cavity of the mold device 101. At this time, the insufficient molding material due to the cooling shrinkage of the molding material can be supplemented in the cavity of the mold device 101.

[0088] Furthermore, the injection molding machine 1 is of an inline screw type, but may be a pre-plasticizing type injection molding machine which is structurally and functionally separated into a plasticizing cylinder and a plasticizing screw, an injection cylinder and an injection plunger.

[0089] (Mobile device)

[0090] The moving device 21 is provided, for example, at the lower portion of the motor box 15 of the injection device 11 , and is an advance / retract drive mechanism that moves the injection device 11 forward and backward relative to the fixed platen 32 a .

[0091] Various mechanisms can be used as the forward and backward driving mechanism constituting the moving device 21, but the moving device 21 shown in the figure is constructed to include: a hydraulic pump 22 such as a hydraulic pump; a pump working motor 23 based on electric power or the like for operating the hydraulic pump 22; and a double-acting hydraulic cylinder 24 that supplies working fluid from the hydraulic pump 22 to enable a piston rod whose front end is fixed to a fixed pressure plate 32a to perform a pushing and pulling movement.

[0092] The moving device 21 further includes a slide base 25 on which the hydraulic pump 22, the pump operating motor 23 and the hydraulic cylinder 24 are mounted, and a guide 26 laid on the base frame 2 and guiding the linear motion of the slide base 25. Thus, the injection device 11 placed on the upper part of the slide base 25 is moved forward and backward.

[0093] The moving device 21 can move the injection device 11 away from the mold device 101 or move the injection device 11 toward the mold device 101 to perform so-called nozzle contact, that is, press the nozzle 12 b of the cylinder 12 of the injection device 11 against the mold device 101 at a predetermined pressure.

[0094] (Injection molding action)

[0095] The control unit can execute the following injection molding operation in order to manufacture a molded product.

[0096] In the latter half of the last molding, with the molding material already measured and arranged in a prescribed amount inside the injection device 11, the clamping device 31 is used to perform a clamping process of bringing the mold device 101 into a closed state, a pressurizing process of pressing the movable mold 103 against the fixed mold 102 until a prescribed clamping force is applied, and a clamping process.

[0097] Next, a filling process is performed in which the molding material is injected into the mold device 101 by advancing the screw 13 to fill the cavity in the mold device 101 with the molding material, and a pressure holding process is performed in which the screw 13 is further advanced to keep the molding material inside the front end of the injection device 11 at a predetermined pressure. At this time, the above-mentioned mold closing compression and / or protrusion compression may also be performed.

[0098] After that, a cooling process is performed, in which the molding material filled in the cavity of the mold device 101 is cooled and solidified to obtain a molded product. At this time, a measuring process is performed, in which the molding material separately put into the injection device 11 is heated by the heater 14 and melted while being conveyed toward the front end of the injection device 11 by the rotation of the screw 13, and a predetermined amount of molding material is arranged at the front end.

[0099] After that, after a depressurization process of operating the mold clamping device 31 to reduce the clamping force on the mold device 101 and a mold opening process of opening the mold device 101, a removal process of removing the molded product from the mold device 101 by moving the movable protrusion 104 through the protrusion driving device 41 is performed.

Claims

1. A control device for an injection molding machine, comprising a control unit, wherein: The mold device installed in the injection molding machine has a movable protrusion, which can move forward and backward relative to the internal space of the mold device and protrude into the internal space by moving forward. The injection molding machine is provided with a protrusion driving device, which drives the movable protrusion of the mold device. The control unit controls the protrusion driving device so that the protrusion amount of the movable protrusion of the mold device into the internal space is limited based on the allowable setting value when the mold device is in the mold-clamped state.

2. The control device according to claim 1, wherein: The control device includes an input unit for a user to input information.

3. The control device according to claim 2, wherein: The user can input the allowable setting value into the input unit.

4. The control device according to claim 2 or 3, wherein: The user can input mold information related to the mold device into the input unit. The control unit determines the allowable setting value based on the mold information input by a user.

5. The control device according to claim 2, wherein: The control unit prohibits a user from inputting the protrusion amount limited by the allowable setting value into the input unit.

6. The control device according to claim 1, wherein: The control unit causes the movable protrusion to move forward and protrude toward the inner space through a protrusion driving device, and determines the allowable setting value according to a forward stop position of the movable protrusion.

7. The control device according to claim 1, wherein: The control device has a display unit for conveying information to the user. The control unit causes the display unit to display the allowable setting value.

8. The control device according to claim 1, wherein: The mold device comprises a fixed mold and a movable mold. The injection molding machine includes a mold clamping device that opens and closes the mold device by separating and approaching a movable mold of the mold device relative to a fixed mold. After the molding material is filled into the internal space of the mold device in a state where the mold device is closed by the mold clamping device, the control unit causes the mold clamping device to perform mold clamping compression, in which the movable mold is further displaced relative to the fixed mold to compress the molding material in the internal space between the fixed mold and the movable mold.

9. The control device according to claim 1, wherein: After the molded product is molded by the molding material filled in the internal space of the mold device, the control unit causes the protrusion drive device to move the movable protrusion forward to protrude into the internal space to remove the molded product from the internal space.

10. A control device for an injection molding machine, comprising a control unit, wherein: The mold device installed in the injection molding machine has a movable protrusion, which can move forward and backward relative to the internal space of the mold device and protrude into the internal space by moving forward. The injection molding machine is provided with a protrusion driving device, which drives the movable protrusion of the mold device. The mold device comprises a fixed mold and a movable mold. The injection molding machine includes a mold clamping device that opens and closes the mold device by separating and approaching a movable mold of the mold device relative to a fixed mold. After the molding material is filled into the internal space of the mold device in a state where the mold device is closed by the mold clamping device, the control unit causes the protrusion driving device to perform protrusion compression, in which the movable protrusion is moved forward to compress the molding material in the internal space by the movable protrusion. The protrusion driving device is controlled by the control unit so as to limit the protrusion amount of the movable protrusion portion of the mold device into the internal space when the protrusion compression is performed based on the allowable set value.

11. The control device according to claim 10, wherein: When the allowable setting value is not set, the control unit prohibits execution of the protrusion compression.

12. The control device according to claim 10, wherein: When the protrusion amount limited by the allowable setting value is planned by a user, the control unit prohibits execution of the protrusion compression.

13. An injection molding machine comprising: The control device according to any one of claims 1 to 12; and The above-mentioned protruding driving device.

14. An injection molding system comprising: The injection molding machine of claim 13; and The mold device is installed on the above injection molding machine.

15. A method for controlling an injection molding machine, wherein: The mold device installed in the injection molding machine has a movable protrusion, which can move forward and backward relative to the internal space of the mold device and protrude into the internal space by moving forward. The injection molding machine is provided with a protrusion driving device, which drives the movable protrusion of the mold device. The control method of the injection molding machine includes controlling the protrusion driving device so as to limit the protrusion amount of the movable protrusion of the mold device into the internal space based on the allowable setting value when the mold device is in the mold clamping state.

16. The control method of the injection molding machine according to claim 15, wherein: include: The user enters the above-mentioned allowable setting value.

17. The control method of an injection molding machine according to claim 15 or 16, wherein: include: The user inputs mold information related to the mold device; as well as Based on the mold information input by the user, the allowable setting value is determined.

18. The control method of the injection molding machine according to claim 15, wherein: include: The user is prohibited from inputting the above-mentioned protrusion amount limited based on the above-mentioned allowable setting value.

19. The control method of the injection molding machine according to claim 15, wherein: include: The movable protrusion is moved forward by a protrusion driving device so as to protrude into the internal space; as well as The allowable setting value is determined according to a forward stop position of the movable protrusion that protrudes into the internal space.

20. The control method of the injection molding machine according to claim 15, wherein: include: The above-mentioned allowed setting values ​​are displayed to the user.

21. The control method of the injection molding machine according to claim 15, wherein: The mold device comprises a fixed mold and a movable mold. The injection molding machine includes a mold clamping device that opens and closes the mold device by separating and approaching a movable mold of the mold device relative to a fixed mold. The control method of the above injection molding machine includes: In a state where the mold device is closed by the mold clamping device, filling the internal space of the mold device with a molding material; and After the internal space is filled with the molding material, the mold clamping device performs mold clamping compression, in which the movable mold is displaced closer to the fixed mold to compress the molding material in the internal space between the fixed mold and the movable mold.

22. The control method of the injection molding machine according to claim 15, wherein: include: forming a molded product from a molding material filled into the inner space of the mold device; as well as After the molded product is molded, the movable protrusion is displaced forward by the protrusion driving device to protrude into the internal space, and the molded product is taken out from the internal space.

23. A method for controlling an injection molding machine, wherein: The mold device installed in the injection molding machine has a movable protrusion, which can move forward and backward relative to the internal space of the mold device and protrude into the internal space by moving forward. The injection molding machine is provided with a protrusion driving device, which drives the movable protrusion of the mold device. The mold device comprises a fixed mold and a movable mold. The injection molding machine includes a mold clamping device that opens and closes the mold device by separating and approaching a movable mold of the mold device relative to a fixed mold. The control method of the above injection molding machine includes: When the mold device is closed by the mold clamping device, the molding material is filled into the inner space of the mold device; After the internal space is filled with the molding material, protrusion compression is performed, in which the movable protrusion is displaced forward by a protrusion driving device to compress the molding material in the internal space by the movable protrusion; and The protrusion driving device is controlled so as to limit the protrusion amount of the movable protrusion portion of the mold device into the internal space when the protrusion compression is performed based on the allowable set value.

24. The control method of the injection molding machine according to claim 23, wherein: include: When the above-mentioned permission setting value is not set, the execution of the above-mentioned protrusion compression is prohibited.

25. The control method of the injection molding machine according to claim 23, wherein: include: When the user plans the protrusion amount limited based on the allowable setting value, execution of the protrusion compression is prohibited.

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