JP2022158668A - Controller of injection molding machine, injection molding machine, injection molding system, and method for controlling injection molding machine - Google Patents

Abstract

To provide a controller of an injection molding machine, an injection molding machine, an injection molding system, and a method for controlling an injection molding machine capable of effectively reducing the risk of damage to a mold assembly.SOLUTION: A controller is used for an injection molding machine and has a control unit. A mold assembly 101 mounted on the injection molding machine has a movable protruding part 104 which is forwardly/backwardly displaceable to/from an inner space Si of the mold assembly 101 and protrudes into the inner space Si by a forward displacement. The injection molding machine is provided with a protrusion driving device 41 for driving the movable protruding part 104 of the mold assembly 101, and controls the protrusion driving device 41 so that a protruding amount into the internal space Si of the movable protruding part 104 of the mold assembly 101 is limited on the basis of an allowable set value by the control unit.SELECTED DRAWING: Figure 3

Description

The present invention relates to 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 includes a protrusion drive device for driving a movable protrusion of a mold device.

An injection molding machine of this type is disclosed, for example, in Japanese Unexamined Patent Application Publication No. 2002-200012.

In Patent Document 1, "a mold clamping device including a platen to which a mold is attached, and an ejector device for ejecting a molded product from the mold, the ejector device includes an ejector rod and an ejector to which the ejector rod is connected. A crosshead and a drive mechanism for advancing and retracting the ejector crosshead, the platen having an opening for connecting the ejector rod and the ejector crosshead, the opening being , which enables access from the external space of the platen to the internal space of the platen, enables access in a direction orthogonal to the mold opening/closing direction, and enables access to the external space through the opening. a switching cover that switches between a first state that allows access to the internal space from and a second state that suppresses scattering of lubricant from the internal space to the external space through the opening; An injection molding machine" is disclosed.
In Patent Document 1, "The movable mold section 840 is arranged to move back and forth inside the fixed mold section 830. The movable mold section 840 is, for example, a plate-like ejector plate perpendicular to the mold opening/closing direction. 841 and a rod-shaped ejector pin 844 extending forward from the ejector plate 841.", "The ejector device 200 performs an ejection process under the control of the control device 700. In the ejection process, the ejector rod 210 is advanced from the standby position to the ejection position at a set moving speed, the movable mold portion 840 is advanced to eject the molded product."

JP 2020-108926 A

An injection molding machine to which a mold device having a movable projecting portion such as the above-mentioned "ejector pin" is attached is provided with a projection driving device such as an "ejector device" for driving the movable projecting portion.

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 brought into the mold clamping state, the protrusion driving device moves the movable protrusion into the internal space of the mold device. When driven to protrude, the movable protrusion may collide with the inner surface of the mold assembly. This can damage the mold set.

In particular, the molding material is clamped and compressed between the fixed mold and the movable mold of the mold device by the mold clamping device, and the molding material is projected and compressed at the movable projection using the projection drive device. In some cases, the risk of damage to the mold device due to the movement of the movable protruding portion described above may become apparent.

SUMMARY OF THE INVENTION An object of the present invention is to solve such problems. An object of the present invention is to provide an injection molding system and a control method for an injection molding machine.

One control device that can solve the above-described problems is used in an injection molding machine and has a control section, and a mold device attached to the injection molding machine is arranged in an internal space of the mold device. The injection molding machine includes a protrusion driving device for driving the movable protrusion of the mold device, and the control unit and controlling a projection driving device such that the amount of projection of the movable projection of the mold device into the internal space is limited based on a set allowable value.

An injection molding machine includes the control device described above and the projection drive device.

An injection molding system includes the injection molding machine described above and a mold apparatus attached to the injection molding machine.

One control method for an injection molding machine that can solve the above-described problems is that a mold device attached to the injection molding machine is movable forward and backward with respect to the internal space of the mold device, and the forward displacement The injection molding machine has a movable protrusion that protrudes into an internal space, the injection molding machine includes a protrusion driving device that drives the movable protrusion of a mold device, and the movable protrusion of the mold device protrudes into the internal space. and controlling the protrusion drive such that the amount is limited based on the tolerance setting.

According to the control device and the control method of the injection molding machine described above, the risk of damage to the mold device can be effectively reduced.

1 is a sectional view showing an injection molding machine in which a control device of one embodiment of the present invention can be used, together with a mold device attached to the injection molding machine; FIG. It is a block diagram showing a control device of one embodiment of this invention. FIG. 2 is an enlarged cross-sectional view of a mold device and main parts of the injection molding machine, showing an example of an injection molding operation using the injection molding machine of FIG. 1; FIG. 4 is a cross-sectional view showing an operation following FIG. 3; FIG. 5 is a cross-sectional view showing an operation following FIG. 4; FIG. 6 is a cross-sectional view showing an operation following FIG. 5; FIG. 7 is a cross-sectional view showing an operation following FIG. 6; FIG. 8 is a cross-sectional view showing the operation following FIG. 7; 3 is a diagram showing part of a setting screen that can be displayed on a display unit of the control device in FIG. 2; FIG. FIG. 3 is a cross-sectional view showing an example of dimensions of a mold device that can be included in mold information that can be input to the input unit of the control device in FIG. 2 ; 3 is a cross-sectional view showing another example of dimensions of a mold device that can be included in mold information that can be input to the input unit of the control device of FIG. 2; FIG.

Embodiments of the present invention will be described in detail below with reference to the drawings.
A control device according to one embodiment of the present invention can be used, for example, in an injection molding machine 1 as shown in FIG. The injection molding machine 1 shown in FIG. 1 generally rotates and advances a screw 13 arranged inside and heats a heater 14 arranged around to melt a molding material such as a thermoplastic resin to form a mold in a mold device 101 . a moving device 21 for moving the injection device 11 forward and backward with respect to the mold device 101; and a projection drive device 41 for driving the movable projecting portion 104 of the mold device 101 .

(Protruding drive device)
The protrusion driving device 41 drives the movable protrusion 104 of the mold device 101 . The mold device 101 is attached to each of the fixed platen 32a and the movable platen 32b of the mold clamping device 31 in addition to the movable projecting portion 104, and an internal space Si including a cavity is defined inside when the mold device 101 is clamped. There may be a fixed mold 102 and a movable mold 103 formed. The mold device 101 is not regarded as a part of the injection molding machine 1 because it can be attached to the injection molding machine 1 or replaced as appropriate according to the shape of the molded product to be manufactured. Here, an injection molding system that includes the injection molding machine 1 and the mold device 101 attached to the injection molding machine 1 is called an injection molding system.

Here, as shown in FIG. 3, the movable protruding portion 104 of the mold apparatus 101 is positioned inside the movable mold 103 on the side of the movable mold 103, and penetrates at least a part of the movable mold 103. It has a pin-like or rod-like shape that extends along the length of the wire. In this example, three pin-shaped movable protrusions 104 are provided, but the number, size and shape of the movable protrusions may be changed as appropriate. Some mold devices have one, two, four or more movable protrusions.

Inside the movable mold 103, the movable protruding portion 104 is capable of advancing and retreating with respect to the internal space Si of the mold device 101. It is provided so as to protrude from Si. On the other hand, when the movable protruding portion 104 is retracted toward the movable platen 32b side (left side in FIG. 3) to which the movable mold 103 is attached, the tip of the movable protruding portion 104 is moved from the internal space Si as shown in FIG. is also recessed toward the movable platen 32b. The movable mold 103 includes two or other appropriate number of projecting plates 105a, which are mutually overlapping with the three movable projecting portions 104 connected to each other on the rear side of the movable projecting portion 104, and the projecting plates 105a. It has a rod-like rod contact member 105b that is fixed on the rear surface or is detachably provided. A later-described projecting rod 42 of the projecting driving device 41 abuts against the rod contact member 105b, and the projecting plate 105a moves back and forth together with the movable projecting portion 104. As shown in FIG.

Further, here, the protrusion drive device 41 shown in the figure includes a protrusion rod 42 that extends inside the movable platen 32b and contacts the rod contact member 105b of the movable mold 103 to displace 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 for moving the. The protrusion driving device 41 causes the above-described forward and backward displacement of the movable protrusion 104 .

The movable protruding part 104 and the protruding driving device 41 are mainly used when taking out a molded product formed by solidifying the molding material injected from the injection device 11 into the internal space Si of the mold device 101 . When a molded product is to be removed from the mold device 101, the mold device 101 is placed in the mold open state shown in FIG. 104 extrudes the molded product from the inside of the mold device 101 . The movable projection 104 is sometimes called an ejector pin, and the projection driving device 41 is sometimes called an ejector device.

(Control device and control method)
The control device used in the injection molding machine 1 has, as shown in FIG. 2, a control section that controls at least the operation of the projection driving device 41. The control unit can be dedicated to the protrusion drive device 41, but in many cases, not only the protrusion drive device 41 but also the injection device 11, the moving device 21, the mold clamping device 31, and other injection molding machines 1 can also control the operation of each device. The control unit includes a protrusion drive source such as a protrusion motor of the protrusion drive device 41 of the injection molding machine 1, various drive sources such as a weighing motor, an injection motor and a mold clamping motor, and various sensors such as temperature and rotation speed. can be connected to

The control device may further include an input unit for inputting information by the user of the injection molding machine 1 and/or a display unit for communicating information to the user, as in the illustrated embodiment. . The input section and/or the display section are each connected to the control section. In a control device having an input section and a display section, at least part of them may be a touch panel. The controller may include a memory connected to the controller for storing information or data. The injection molding machine 1 may be equipped with such a control device.

In the above-described protrusion driving device 41 and the mold device 101, if the user does not set the injection molding operation correctly, the movable protrusion 104 will move to the protrusion driving device when the mold device 101 enters the mold clamping state. 41 to protrude greatly into the internal space Si of the mold device 101 . In this case, the tip of the movable projecting portion 104 moving forward toward the fixed mold 102 collides with the inner surface of the mold device 101, more specifically, the inner surface defining the internal space Si of the fixed mold 102, and the tip Damage to the mold device 101 may occur at the part or the like.

In order to cope with this, the control device of this embodiment is configured so that the control unit limits the amount of protrusion of the movable protruding portion 104 of the mold device 101 into the internal space Si based on a predetermined allowable set value. It controls the protrusion drive device 41 . The allowable set value may be, for example, the amount of protrusion of the movable protrusion 104 when the tip of the movable protrusion 104 contacts the inner surface of the fixed mold 102, and is set in advance before execution of the injection molding operation. be. In this case, the control device can control the protrusion driving device 41 so that the amount of protrusion of the movable protrusion 104 into the internal space Si does not exceed the allowable set value.

With this control, collision of the movable protruding portion 104 with the inner surface of the mold apparatus 101 is avoided when the mold apparatus 101 is placed in the mold clamping state, so damage to the mold apparatus 101 is effectively suppressed. can do.

By the way, the illustrated mold device 101 is configured so that the molding material can be clamped and compressed between the fixed mold 102 and the movable mold 103 by the mold clamping device 31 .

More specifically, in this mold apparatus 101 as an example, the movable mold 103 includes, in order from the movable platen 32b side toward the fixed mold 102 side, a movable side mounting plate 106 attached to the movable platen 32b, A spacer block 107 defining a space Se in which the above-mentioned projecting plate 105a is arranged, a receiving plate 108 provided with an elastic member 108a, and a movable side mold plate 109 facing the fixed mold 102 are provided. is.

The movable mold plate 109 of the movable mold 103 is fixedly attached to the surface of the receiving plate 108 on the fixed mold 102 side. It is divided into a plurality of members including a pressure member 109b which is supported via a member 108a and pressed against the stationary mold 102 when a mold clamping force is applied. As shown in FIG. 3, the direction in which the movable platen 32b approaches the stationary platen 32a (the horizontal direction in FIG. 3, also referred to as the "moving direction of the movable platen") is perpendicular to the direction (vertical direction in FIG. 3). 2, two material pressing members 109a and three pressing members 109b each having a block shape or the like are arranged alternately.

Each of the receiving plate 108 and the three material pressing members 109a and 109b positioned inside in the direction orthogonal to the moving direction of the movable platen has a through hole extending from the space Se of the protruding plate 105a to the internal space Si. is formed, inside each of those through-holes, each of the plurality of movable protrusions 104 described above is inserted and arranged.

The elastic member 108a provided on the receiving plate 108 can be a spring member such as a coil spring that resists the mold clamping force acting in the moving direction of the movable platen. It may be a cylinder that moves 109b.

The illustrated fixed mold 102 includes a fixed side mounting plate 110 attached to the fixed platen 32a, and a fixed side template 111 provided on the surface of the fixed side mounting plate 110 on the movable mold 103 side. A sprue bushing 112 is provided approximately in the central region of the fixed side mounting plate 110 and the fixed side mold plate 111 . A sprue 112a is formed inside the sprue bushing 112 to guide the molding material Mm injected from the injection device 11 to the internal space Si.

The mold apparatus 101 can be provided with a gap measuring device 121 used to grasp the gap between the material pressing member 109a and the stationary mold plate 111 in the moving direction of the movable platen. Here, the distance measuring device 121 includes a non-contact type displacement sensor 122 attached around the receiving plate 108 and a target 123 attached at a position facing the displacement sensor 122 around the movable template 109. and However, the mounting positions of the displacement sensor and the target can be interchanged, and one of them is mounted on the spacer block 107 or the like instead of the receiving plate 108, and the other is mounted on the fixed side template 111 or the like instead of the movable side template 109. can also Alternatively, a distance measuring device including a contact-type displacement sensor may be used.

When the mold device 101 as described above is attached to the injection molding machine 1, the control unit of the control device can perform mold clamping compression of the molding material Mm, for example, as described below.

First, with the mold apparatus 101 in the mold open state shown in FIG. to the mold closed state. At this time, the pressure member 109b of the movable mold 103 contacts the fixed-side mold plate 111 of the fixed mold 102, but almost no clamping force acts on the mold apparatus 101, and the pressure member 109b and the pressure member 109b The elastic member 108a between the receiving plate 108 is substantially uncompressed.

Next, as shown in FIG. 5, the movable mold 103 is moved closer to the fixed mold 102 by the mold clamping device 31, compressing the elastic member 108a, and pressing the pressure member 109b against the stationary mold plate 111. impose. Thereby, a cavity is defined in the internal space Si of the mold device 101 . Here, due to the restoring force of the compressed elastic member 108a, the pressing member 109b is pressed against the fixed side mold plate 111 with a predetermined mold clamping force. As a result, between the pressure member 109b and the stationary mold plate 111, the occurrence of burrs in the molded product molded after the cavity is filled with the molding material Mm, as will be described later, is suppressed.

After that, the molding material Mm accumulated at the tip of the cylinder 12 of the injection device 11 is injected from the nozzle 12b. As shown in FIG. 6, the molding material Mm injected from the injection device 11 passes through the sprue 112a inside the sprue bushing 112, reaches the internal space Si of the mold device 101, and fills the internal space Si. . In this example, of the pressure members 109b supported by the elastic members 108a of the movable side mold plate 109 of the movable mold 103, the central pressure member 109b facing the sprue 112a has its opposite surface It is formed in a shape recessed toward the movable platen 32b from the parting line, which is the boundary between the pressure member 109b and the fixed-side template 111. As shown in FIG. A space in the internal space Si between the central pressure member 109b and the stationary template 111 functions as a runner. Gates 109c are formed between the central pressure member 109b and the material pressing members 109a adjacent to it on both sides to allow the molding material Mm to flow into the cavity of the internal space Si on the material pressing member 109a side (FIG. 5). reference).

After the interior space Si of the mold device 101 is filled with the molding material Mm to some extent, as shown in FIG. The mold 102 is further displaced to compress the molding material Mm in the internal space Si between the fixed mold 102 and the movable mold 103 . When mold clamping compression is performed, even when a relatively thin molded product is molded, the molding material Mm is sufficiently spread over the entire cavity of the internal space Si, thereby effectively preventing the occurrence of molding defects such as sink marks. can do. In mold clamping compression, the gap between the material pressing member 109a and the stationary mold plate 111 and the amount of compression of the elastic member 108a can be adjusted based on the values measured by the gap measuring device 121 and the like.

In addition to the mold clamping compression described above, or without executing the mold clamping compression, the control unit can execute projection compression for compressing the molding material Mm with the movable projection 104 using the projection driving device 41 .

When both clamping compression and projection compression are performed, before filling the molding material Mm into the internal space Si of the mold device 101, as shown in FIG. The portion 104 is displaced backward so that the tip portion of the movable protruding portion 104 is arranged in the through hole at a position deeper than the internal space Si.

In this state, as shown in FIG. 6, when the molding material Mm is injected from the injection device 11 and filled into the internal space of the mold device 101, the through hole into which the movable protruding portion 104 is inserted is filled with the molding material Mm. The molding material Mm also enters the gap up to the tip. Then, the mold clamping compression shown in FIG. 7 is performed as described above.

During or after the mold clamping compression, the movable projection 104 is driven by the projection driving device 41 as projection compression, and as shown in FIG. , the movable protruding portion 104 is displaced forward. As a result, the molding material Mm that has entered the through hole into which the movable projecting portion 104 is inserted is pushed out into the internal space Si by the movable projecting portion 104 moving forward, and the molding material Mm in the internal space Si is compressed. .

After that, the molding material Mm is cooled and hardened in the internal space Si to form a molded product. After molding the molded product in the internal space Si, the control unit puts the mold device 101 into a mold open state (not shown), and causes the projection driving device 41 to advance and displace the movable projecting portion 104 into the internal space Si. It can be made to protrude and take out the molded product from the internal space Si.

In the case of performing mold clamping compression and projection compression as described above, if the user sets the operation of the projection driving device 41 incorrectly, the problem of damage to the mold device 101 may become apparent. That is, when the movable projecting portion 104 protrudes greatly into the internal space Si before or during mold clamping compression, and the tip of the movable projecting portion 104 hits the inner surface of the fixed mold 102, after that, the mold clamping compression causes a large mold A clamping force acts on the movable protrusion 104 . As a result, the risk of damage to the mold apparatus 101 such as breakage of the movable projecting portion 104 increases. Therefore, this embodiment is particularly advantageous because it can reduce the above-described risk of damage to the mold device 101 when the control section of the control device executes mold clamping compression or protrusion compression.

In order to effectively reduce such damage risk, the control unit prohibits the user from executing the above-described projection compression when the allowable set value used for limiting the projection amount of the movable projection 104 is not set. is preferred. For example, if the allowable set value is not set, the control unit prevents the user from selecting the execution of the projection compression in the input unit, or even if the execution is selected, the injection molding operation including the projection compression starts. You can prevent it from happening. Further, the control unit may make the user aware that the allowable setting value is not set by displaying on the display unit, by an alarm, or the like.

When executing the protrusion compression, the user can input and set the amount of protrusion in one step or multiple steps when the protrusion driving device 41 advances the movable protrusion 104 during the protrusion compression. As an example, FIG. 9 shows a display portion 201 related to the amount of projection of the movable projecting portion 104 in a setting screen that can be displayed on the display unit by the control unit. In this example, four stages of protrusion amount from 1st to 4th of the movable protrusion 104 can be set in executing the protrusion compression.

Here, the user inputs, from the input unit, the amount of protrusion that is limited based on the allowable set value, for example, the amount of protrusion that exceeds the allowable set value, as the amount of protrusion of the movable protrusion 104 in at least one stage from 1st to 4th. When intended to do so, the controller preferably inhibits the execution of projective compression. Further, the control unit may prohibit the user from inputting the amount of protrusion limited based on the allowable set value to the input unit. This is because the risk of damage to the mold device 101 increases when the operation of the protrusion driving device 41 such as protrusion compression is performed with such a protrusion amount. If necessary, for example, using the display unit, the user is provided with a suggestion that the execution of the protrusion compression is prohibited, or that the input of the protrusion amount limited by the allowable set value is prohibited.

The preset allowable set value is preferably displayed on the display unit as shown as "limit position" in FIG. As a result, the user can easily confirm that the allowable set value is set, that the protrusion compression can be executed, and that the allowable set value is the upper limit of the amount of protrusion that can be input in each step. can be recognized.

The allowable setting value can be set by the user deciding and inputting from the input unit. In this case, the protrusion driving device 41 can be controlled based on the allowable setting value set by the user.

In addition to or instead of enabling the user to input the allowable setting value, the user can input mold information regarding the mold apparatus to the input unit, and the control unit controls the mold information input by the user. It is preferable to determine the allowable settings from.

This mold information may include information about the dimensions of the mold apparatus 101 . Specifically, as the mold information, for example, as shown in FIG. There is a separation distance D1 between the inner surface of the fixed mold 102 and the inner surface of the movable mold. The separation distance D1 is the maximum amount of protrusion of the movable protruding portion 104 that can protrude into the internal space Si in the clamped state, and the control unit may set this as an allowable set value.

As shown in FIG. 11, the mold information is the projection rod 42 position of the rod contact member 105b of the mold device 101 when the projection rod 42 of the projection drive device 41 is retracted most in the moving direction of the movable platen. may include a separation distance D2 from the tip of the . The sum of the separation distances D1 and D2 is the allowable set value for the stroke amount of the protruding rod 42, and the control unit may control the protrusion drive device 41 based on such an allowable set value for the stroke amount. good. The "limit position" in FIG. 9 described above is the allowable set value of the stroke amount of the projecting rod 42 (the stroke amount from the most advanced position of the tip of the projecting rod 42 to the most allowed advanced position).

Further, in order to determine the allowable setting value for the mold device 101 attached to the injection molding machine 1, the control unit moves the movable projection 104 forward by the projection drive device 41 in the mold device 101 in the clamped state, for example. can be projected into the internal space Si. When the movable protruding portion 104 hits the inner surface of the mold device 101 and stops due to this forward displacement, the control section can determine the allowable set value from the forward stop position of the movable protruding portion 104 .

Here, since the movable protruding portion 104 is moved forward for the purpose of determining the allowable set value, it is not necessary to fill the internal space Si of the mold device 101 with the molding material. When the mold device 101 is replaced with a different mold device 101, the control unit can determine the allowable set value by the forward displacement of the movable protruding portion 104 prior to executing the injection molding operation. It should be noted that such forward displacement of the movable projecting portion 104 is preferably driven by the projection driving device 41 with relatively low torque so as not to damage or break the mold device 101 .

(mold clamping device)
The mold clamping device 31 displaces the movable mold 103 toward or away from the fixed mold 102 of the mold device 101 to open and close the mold device 101, and puts the mold device 101 into a clamped state and a mold closed state. state or mold open state. This mold clamping device 31 has a platen 32 including a stationary platen 32 a and a movable platen 32 b and a platen operating mechanism 33 for operating the platen 32 .

Of the platens 32 , the stationary platen 32 a is fixedly attached to 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 separating from and approaching the fixed platen 32a. The mold clamping device 31 is provided with one or a plurality of tie bars 32c that extend from the fixed platen 32a to the rear platen 34 side to connect the fixed platen 32a and the rear platen 34 to each other. In this example, the movable platen 32b is guided by the tie bars 32c in movement toward and away from the stationary platen 32a, but it is not necessary to be guided by the tie bars 32c.

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

Among them, the motion conversion mechanism 36 can be various mechanisms capable of converting rotary motion into linear motion. It is assumed to include a mating nut 36b. It is also possible to use the motion conversion mechanism 36 as a ball screw.

The toggle mechanism 37, which increases 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 platen 34 and nut 36b to the movable platen 32b with joints. be.
Although the number and shape of the links and joints can be changed as appropriate, as shown in FIG. A pair of link groups consisting of positioned links 37a to 37c are provided to be pivotally connected.

In addition to the mold clamping motor 35 described above, a mold thickness adjusting motor 38 can also be provided on the rear platen 34 . The die thickness adjusting motor 38 is movable on the stationary platen 32a and the base frame 2 by applying rotational driving force to the screw shaft and nut connected to the extension portions of the respective tie bars 32c of the platen 32. It functions to adjust the distance from the mounted rear platen 34 . As a result, even when the mold device 101 is replaced or when the thickness of the mold device 101 is changed due to a change in temperature, a desired mold clamping force can be applied to the mold device 101. Mold thickness can be adjusted. Although not shown, the mold thickness can be adjusted by making the fixed platen side movable on the base frame 2 and fixing the rear platen side.

The illustrated mold clamping device 31 is of a horizontal type in which the moving direction of the movable platen 32b is parallel to the horizontal direction, but it can also be of a vertical type in which the moving direction is vertical.

(Injection device)
The injection device 11 mainly includes a cylindrical cylinder 12 extending toward the mold device 101, and a screw arranged inside the cylinder 12 with its central axis parallel to it, and having spiral flights around the periphery. 13 , a band-like heater 14 arranged on the outer peripheral side of the cylinder 12 so as to surround the periphery thereof, and a motor box 15 arranged behind the cylinder 12 and the screw 13 . Although not shown, the motor box 15 contains a metering motor that rotates the screw 13 around the central axis in order to accumulate a predetermined amount of molding material at the tip of the cylinder 12, and a motor that approaches the mold device 101. An injection motor that advances and retreats the screw 13 in each direction of direction and direction away from the mold device 101, a pressure detection sensor that detects the pressure that the screw 13 receives from the molding material, and the like are arranged.

Here, the direction toward the fixed platen 32a of the mold clamping device 31 to which the fixed mold 102 of the mold device 101 is attached is defined as the front side, and the direction away from the fixed platen 32a is defined as the rear side. Looking at the injection device 11 located on the right side of the stationary platen 32a in FIG. 1, the left side approaching the stationary platen 32a is the front side, and the right side away from the stationary platen 32a is the rear side.

The cylinder 12 is provided with a supply port 12 a to which a hopper for charging the molding material into the cylinder 12 can be attached on the rear side in front of the motor box 15 . A nozzle 12b having a smaller cross-sectional area on the front side is provided at the tip of the cylinder 12 adjacent to the mold device 101 . A water-cooled cylinder 12c can be provided in the vicinity of the supply port 12a.

The heater 14 arranged around the cylinder 12, including around the nozzle 12b, is divided into a plurality of parts in the cylinder axial direction, for example, as shown in the drawing, and the inside of the cylinder 12 inside each heater part is heated at a different temperature. It can be heatable. Each heater section may be provided with a temperature detector.

Although not shown, the tip of the screw 13 is displaced forward and backward together with the screw 13 around a constricted portion provided by partially reducing the outer diameter of the molding material. A backflow prevention ring may be arranged to prevent backflow to the rear side of the The anti-backflow ring is displaced back and forth with respect to the screw 13 in response to pressure received from the molding material positioned forward or rearward, thereby causing the molding material to flow from the rear side to the front side. Only flow is allowed.

According to the injection apparatus 11 having such a configuration, the molding material introduced into the cylinder 12 from the supply port 12a is heated by the heater 14 on the outer peripheral side of the cylinder 12 and driven by the metering motor in the metering process. While being melted based on the rotation of the screw 13 , it is fed forward inside the cylinder 12 and accumulated at the tip of the cylinder 12 . At this time, the screw 13 is moved backward by the injection motor to form a space in which the molding material is accumulated at the tip of the cylinder 12 .

After that, in the filling step, by moving the screw 13 forward, the molding material at the tip of the cylinder 12 is injected toward the mold device 101 through the nozzle 12b. Furthermore, in the subsequent pressure holding step, pressure is applied to the molding material filled in the cavity of the mold device 101 through the molding material remaining at the tip of the cylinder 12 . At this time, the shortage of molding material due to cooling shrinkage of the molding material in the cavity of the mold device 101 can be replenished.

Although this injection molding machine 1 is of the in-line screw type, it may be a pre-plasticization injection molding machine in which the plasticizing cylinder and plasticizing screw are separated from the injection cylinder and injection plunger in terms of structure and function. is also possible.

(moving device)
The moving device 21 is provided, for example, in the lower portion of the motor box 15 of the injection device 11, and is a forward/backward drive mechanism that moves the injection device 11 forward and backward with respect to the stationary platen 32a.
Various mechanisms can be employed as the advance/retreat drive mechanism that constitutes the moving device 21. The moving device 21 shown in the figure includes a hydraulic pump 22 such as hydraulic pressure, and an electric pump operation for operating the hydraulic pump 22. and a double-acting hydraulic cylinder 24 that receives hydraulic fluid from the hydraulic pump 22 and pushes and retracts a piston rod whose tip is fixed to the fixed platen 32a. .

This moving device 21 is laid on a slide base 25 to which the above-described hydraulic pump 22, pump operating motor 23 and hydraulic cylinder 24 are attached, and on the base frame 2 to guide the linear movement of the slide base 25. It further includes a guide 26 for. As a result, the injection device 11 mounted on the upper portion of the slide base 25 can be moved back and forth.

The moving device 21 separates the injection device 11 from the mold device 101 or moves the injection device 11 closer to the mold device 101 to move the nozzle 12b of the cylinder 12 of the injection device 11 to the mold device with a predetermined pressure. It is possible to perform so-called nozzle touch, that is, to press against 101 .

(Injection molding operation)
The controller can perform injection molding operations, such as those described below, to produce molded articles.

In a state in which a predetermined amount of molding material has already been weighed and placed inside the injection device 11 in the second half of the previous molding, the mold device 101 is closed using the mold clamping device 31. A closing process and a pressurizing process and a mold clamping process of pressing the movable mold 103 against the fixed mold 102 until a predetermined mold clamping force acts are performed.

Next, the screw 13 is advanced to inject the molding material into the mold device 101 to fill the cavity in the mold device 101 with the molding material. and a holding pressure step of holding the molding material inside the tip portion at a predetermined pressure. At this time, the mold clamping compression and/or extrusion compression described above may be performed.

After that, the molding material filled in the cavity of the mold device 101 is cooled and solidified to obtain a molded product. At this time, the molding material separately put into the injection device 11 is melted while being sent toward the tip of the injection device 11 by rotating the screw 13 under heating by the heater 14, and a predetermined amount of the molding material is melted at the tip. A weighing step is performed to place the

After that, the mold clamping device 31 is actuated to reduce the mold clamping force on the mold device 101, and the mold opening step opens the mold device 101. After that, the movable protrusion 104 is is moved to perform a take-out step of taking out the molded product from the mold device 101 .

REFERENCE SIGNS LIST 1 injection molding machine 2 base frame 11 injection device 12 cylinder 12a supply port 12b nozzle 12c water cooling cylinder 13 screw 14 heater 15 motor box 21 moving device 22 hydraulic pump 23 pump operating motor 24 hydraulic cylinder 25 slide base 26 guide 31 mold Clamping device 32 Platen 32a Fixed platen 32b Movable platen 32c Tie bar 32d Guide member 33 Platen operating mechanism 34 Rear platen 35 Mold clamping motor 36 Motion conversion mechanism 36a Screw shaft 36b Nut 37 Toggle mechanism 37a to 37c Link 37d Crosshead 38 Mold thickness adjustment motor 41 Projection drive device 42 Projection rod 43 Projection drive source 101 Mold device 102 Fixed mold 103 Movable mold 104 Movable projecting part 105a Projecting plate 105b Rod contacting member 106 Movable mounting plate 107 Spacer block 108 Receiving plate 108a Elastic member 109 Movable Side mold plate 109a Material pressing member 109b Pressure member 109c Gate 110 Fixed side mounting plate 111 Fixed side mold plate 112 Sprue bush 112a Sprue 121 Distance measuring device 122 Displacement sensor 123 Target 201 Display part of display part D1, D2 Separation distance Mm Molding Material Se Space Si Internal space

Claims (25)

A control device used in an injection molding machine and having a control unit,
A mold device attached to the injection molding machine has a movable projecting portion that is movable forward and backward with respect to an internal space of the mold device and projects into the internal space by forward displacement,
The injection molding machine comprises a protrusion driving device for driving the movable protrusion of the mold device,
A control device for controlling a projection driving device such that the control unit limits the amount of projection of the movable projection of the mold device into the internal space based on a set allowable value. 2. The control device according to claim 1, further comprising an input unit used for inputting information by a user. 3. The control device according to claim 2, wherein a user can input the allowable setting value to the input section. A user can input mold information related to the mold apparatus to the input unit,
4. The control device according to claim 2 or 3, wherein the control unit determines the allowable set value based on the mold information input by a user. 5. The control device according to any one of claims 2 to 4, wherein the control unit prohibits a user from inputting the amount of protrusion limited based on the allowable set value to the input unit. 6. The allowable set value according to any one of claims 1 to 5, wherein the control unit advances the movable projecting portion by a projection drive device to project it into the internal space, and determines the allowable set value from the forward stop position of the movable projecting portion. A control device according to any one of the preceding paragraphs. The control device has a display unit used to convey information to a user,
The control device according to any one of claims 1 to 6, wherein the control section causes the display section to display the allowable set value. The mold device has a fixed mold and a movable mold,
The injection molding machine comprises a mold clamping device that opens and closes the mold device by displacing the movable mold away from and displacing the movable mold with respect to the fixed mold of the mold device,
After the mold device is closed by the mold clamping device and the molding material is filled into the internal space of the mold device, the control unit causes the mold clamping device to displace the movable mold further closer to the fixed mold. The control device according to any one of claims 1 to 7, which performs mold clamping compression for compressing the molding material in the internal space between a fixed mold and a movable mold. 9. The control unit according to claim 8, wherein after the mold clamping compression, the protrusion driving device advances the movable protrusion to perform protrusion compression for compressing the molding material in the internal space by the movable protrusion. controller. 10. The control device according to claim 9, wherein said control unit prohibits execution of said projection compression when said allowable set value is not set. 11. The control device according to claim 9 or 10, wherein the control unit prohibits execution of the projection compression when the user intends the projection amount to be limited based on the allowable set value. After the control unit molds a molded product from the molding material filled in the internal space of the mold device, the projection driving device causes the movable projecting portion to move forward and project into the internal space, and then from the internal space. 12. The control device according to any one of claims 1 to 11, wherein the molded product is taken out. An injection molding machine comprising the control device according to any one of claims 1 to 12 and the projection drive device. An injection molding system comprising the injection molding machine according to claim 13 and a mold device attached to the injection molding machine. A method of controlling an injection molding machine comprising:
A mold device attached to the injection molding machine has a movable projecting portion that is movable forward and backward with respect to an internal space of the mold device and projects into the internal space by forward displacement,
The injection molding machine comprises a protrusion driving device for driving the movable protrusion of the mold device,
A control method for an injection molding machine, comprising controlling a protrusion driving device such that the amount of protrusion of the movable protrusion of the mold device into the internal space is limited based on a set allowable value. 16. The method of controlling an injection molding machine according to claim 15, comprising a user inputting said tolerance setting. a user inputting mold information about the mold apparatus; and
17. The method of controlling an injection molding machine according to claim 15 or 16, comprising determining allowable setting values based on said mold information input by a user. 18. The method of controlling an injection molding machine according to any one of claims 15 to 17, further comprising prohibiting a user from inputting the amount of projection limited based on the allowable set value. forwardly displacing the movable projecting portion by a projection driving device to project it into the internal space;
19. The method of controlling an injection molding machine according to any one of claims 15 to 18, comprising determining said allowable set value from an advance stop position of said movable projecting portion projecting into said internal space. 20. The method of controlling an injection molding machine according to any one of claims 15 to 19, comprising displaying said allowable setting value to a user. The mold device has a fixed mold and a movable mold,
The injection molding machine comprises a mold clamping device that opens and closes the mold device by displacing the movable mold away from and displacing the movable mold with respect to the fixed mold of the mold device,
Filling the internal space of the mold device with a molding material while the mold device is closed by the mold clamping device;
After filling the internal space with the molding material, the mold clamping device displaces the movable mold further closer to the fixed mold to compress the molding material in the internal space between the fixed mold and the movable mold. The method for controlling an injection molding machine according to any one of claims 15 to 20, comprising performing mold clamping compression. 22. Injection molding according to claim 21, comprising: after the mold clamping compression, forwardly displacing the movable protrusion by a protrusion drive device, and performing protrusion compression for compressing the molding material in the internal space by the movable protrusion. machine control method. 23. The method of controlling an injection molding machine according to claim 22, comprising prohibiting execution of said projection compression when said allowable set value is not set. 24. The method of controlling an injection molding machine according to claim 22 or 23, comprising prohibiting execution of said protrusion compression when a user intends said protrusion amount to be limited based on said allowable set value. Molding a molded product from the molding material filled in the internal space of the mold device;
25. The method according to any one of claims 15 to 24, wherein after molding the molded product, the movable projecting portion is moved forward by a projection drive device to project into the internal space, and the molded product is taken out from the internal space. A method of controlling the described injection molding machine.

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