KR20160077638A - Injection molding machine and method for controlling the injection molding machine - Google Patents

Abstract

The present invention relates to an injection molding machine which allows operation of a normal toggle link without pushing a driving mold plate backwardly during the operation in an injection compression mode in an injection molding machine provided with a toggle type shaping device, and a method for controlling the same. The injection molding machine according to the present invention comprises: a fixed mold plate to which fixed mold is mounted; a driving mold plate opposite to the fixed mold plate, receiving a driving mold opposite to the fixed mold and driven by a toggle system; a metallic member disposed on at least one side of the fixed mold plate; an electromagnet mounted to at least one side of the driving mold plate in opposite to the metallic member; and a controlling device for controlling the toggle system so that a predetermined gap between the driving mold plate and the fixed mold plate is maintained by turning-on the electromagnet upon the formation of the gap when carrying out an injection compression mode by moving the driving mold plate toward the fixed mold plate.

Description

TECHNICAL FIELD [0001] The present invention relates to an injection molding machine and a control method thereof. BACKGROUND OF THE INVENTION 1. Field of the Invention [0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an injection molding machine, and more particularly, to an injection molding machine and a control method thereof for maintaining mold opening in an injection compression mode.

An injection molding machine injects a molten resin from an injection apparatus, charges it into a cavity of a mold apparatus, and solidifies it to mold the molded article. The mold apparatus comprises a stationary mold and a movable mold. Molding, mold clamping and mold clamping of the mold apparatus are performed by a mold clamping apparatus. The mold clamping apparatus includes a movable mold plate, a fixed mold plate, a drive source such as a motor for moving the movable mold plate, and a toggle mechanism.

The general injection mode of an injection molding machine is as follows. The movable mold plate of the mold clamping device, which is initially in the open state, is moved at a high speed in the direction of the fixed mold plate. When the movable mold provided on the movable mold plate is brought into contact with the fixed mold provided on the fixed mold plate according to the movement of the movable mold plate, the mold pressure is increased by increasing the pressure. Then, the nozzle of the injection apparatus is advanced to the mold, and the resin is injected and cooled. Thereafter, the movable mold plate of the mold clamping apparatus is retracted backward to separate the movable mold and the fixed mold, and finally the movable mold plate is retracted at a high speed to take out the injection molded article.

In this general injection mode, the gap between the movable mold and the stationary mold is not maintained in the mold closing and mold-clamping process, and the movable mold and the stationary mold are held in close contact with each other, and then the resin is injected. Therefore, it requires a large amount of force for a long time. In order to solve such a problem, an injection compression mode in which a fixed amount of resin is filled in a cavity of a mold after the fixed gap is maintained without directly contacting the movable mold and the fixed mold in the mold closing process, and then the movable mold and the stationary mold are closely contacted .

In the mold closing process, when the movable mold and the stationary mold are not in direct contact with each other and a constant gap is maintained, only a small mold force is required as compared with when the movable mold and the stationary mold are directly in close contact with each other. For example, when a gap of 0.1 mm or less is maintained between the movable mold and the stationary mold, a clamping force of about 95% of the mold clamping force is required when the movable mold and the stationary mold are closely contacted. When a gap of 0.5 mm is maintained between the movable mold and the stationary mold, a clamping force of about 70% of the mold clamping force is required when the movable mold and the stationary mold are closely contacted.

However, in a state in which the movable mold and the fixed mold are not in direct contact with each other and a constant gap is maintained between the molds, the toggle type mold clamping device is not fully opened, and the pressure of the resin filled in the mold cavity, A phenomenon of pushing back occurs. In severe cases, when the mold is closely contacted, the movable mold plate does not advance in the direction of the stationary mold due to the pressure of the resin filled in the cavity, so that no contact between the molds occurs at all. This poses a problem that the defective injection molded article is taken out.

The present invention has been made in order to solve the above-mentioned problems, and it is an object of the present invention to provide an injection molding machine and a control method thereof, which enable a normal toggle link to be operated without pushing a movable mold plate in an injection compression mode in an injection molding machine having a toggle mold clamping device The purpose is to provide.

According to an aspect of the present invention, there is provided an injection molding machine including: a stationary mold to which a stationary mold is mounted; A movable plate disposed to face the stationary plate and mounted with a movable mold facing the stationary mold, the movable plate being moved by a toggle mechanism; A metal member mounted on at least one side surface of the fixed plate; An electromagnet mounted on at least one side of the movable plate opposite to the metal member; And a controller for controlling the toggle mechanism to move the movable plate in the direction of the fixed plate to perform the injection compression mode, and when the gap is formed between the movable mold and the stationary mold, the electromagnet is turned on to maintain the gap, .

Wherein the injection molding machine further includes a mold auxiliary drive unit having a shaft to which the electromagnet is attached and which is capable of rectilinear reciprocating motion, wherein the control unit controls the attraction force for holding the gap between the electromagnet and the metal member So that the axis can be linearly moved by controlling the mold clamping sub-driver.

The control device controls the mold clamping sub-driver so that the electromagnet and the metal member are in contact with each other when the gap is formed, so that the axis can linearly move.

The control device moves the movable plate when the resin is charged by a predetermined amount to the cavity between the stationary mold and the movable mold to closely contact the stationary mold and the movable mold.

The controller may control the mold clamping sub-driver to turn the electromagnet backward in a direction opposite to the gap by an amount equal to or greater than the gap before the fixed mold and the movable mold are brought into close contact with each other.

Wherein the mold auxiliary driving portion is a motor having a hollow formed therein, wherein a ball screw nut is provided inside the rotor, the shaft is a ball screw shaft corresponding to the ball screw nut, It is possible to perform linear motion during rotation.

The metal member may be installed at upper and lower ends of both sides of the fixed plate, and the electromagnet may be installed at the upper and lower ends of both sides of the movable plate.

The gap may be 0.1 mm to 0.5 mm.

According to another aspect of the present invention, there is provided an injection molding machine including a mold clamping device including a toggle mechanism for moving a movable mold having a movable mold mounted thereon to and from a fixed mold having a fixed mold mounted thereon, A step of setting a gap between the movable mold and the fixed mold in an injection compression mode; Controlling the toggle mechanism to move the movable plate in the direction of the fixed plate and determining whether the movable mold has reached a position spaced from the stationary mold by the gap; And maintaining the gap by turning on an electromagnet mounted on at least one side of the movable plate against a metal member mounted on at least one side of the fixed plate.

Wherein said electromagnet is installed on a shaft which is capable of linear reciprocating motion so as to face said metal member, and said step of setting said gap is a step of moving said shaft in a linear motion so as to generate attraction force for holding said gap between said electromagnet and said metal member ; And < / RTI >

The method includes filling a cavity between the stationary mold and the movable mold with resin; And moving the movable mold when the resin is filled with a predetermined amount of the cavity to bring the fixed mold and the movable mold into close contact with each other.

The step of tightening may include retracting the shaft in a direction opposite to the metal member by more than the gap after the electromagnet is turned off before the fixed mold and the movable mold are brought into close contact with each other.

The shaft is a ball screw shaft, which is inserted into the hollow of a motor having a hollow and provided with a ball screw nut on the inner side of the rotor, so as to perform linear motion when the rotor is rotated.

When the movable mold and the stationary mold maintain a predetermined gap when the injection molding machine is driven in the injection compression mode, the gap is maintained by using the electromagnets and the metal member installed in the mold, so that the movable mold plate is not pushed back and the normal toggle link is operated .

The present invention can reduce the mold clamping force by the toggle mechanism by maintaining a constant gap between the movable mold and the stationary mold by using the electromagnet and the metal member in the injection compression mode, and thus the mechanical life of the injection molding machine can be extended.

1 is a view showing an example of an injection molding machine to which the present invention is applied.
Fig. 2 is a detailed view of the mold clamping apparatus of Fig. 1. Fig.
Figure 3 is a partial perspective view of Figure 2;
Fig. 4 is a cross-sectional view of the mold auxiliary motor and the shaft of Fig. 3;
5 is a flowchart illustrating a control method of an injection molding machine according to an embodiment of the present invention.

The foregoing and other objects, features and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings, in which: There will be. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail. Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 is a view showing a schematic configuration of a screw-type motor-driven injection molding machine as an example of an injection molding machine to which the present invention is applied.

The injection molding machine 1 shown in Fig. 1 comprises a frame 10, an injection apparatus 20 and a mold clamping apparatus 50 arranged on the frame 10, and the like.

The injection apparatus 20 has a heating cylinder 21, and a hopper 22 is installed in the heating cylinder 21. A heater 21a for heating the heating cylinder 21 is provided on the outer periphery of the heating cylinder 21. [ A screw (23) is installed in the heating cylinder (21) so as to be movable forward and backward. The rear end of the screw (23) is rotatably supported by the movable support portion (24).

A weighing motor 25 such as a servomotor is mounted as a driving portion to the movable support portion 24. The rotation of the weighing motor 25 is transmitted to the screw 23 through the timing belt 26 mounted on the output shaft 31.

A rotation detector 32 is connected to the rear end of the output shaft 31. The rotation detector 32 detects the rotation speed of the screw 23 by detecting the rotation speed or the rotation amount of the weighing motor 25. [

The injection apparatus 20 has a ball screw shaft 27 parallel to the screw 23. The ball screw shaft 27 is screwed to the ball screw nut 90 to constitute a motion direction changing mechanism for converting rotational motion into linear motion. When the ball screw shaft 27 is rotated through the timing belt 28 by driving the injection motor 29 as the driving unit, the movable support portion 24 and the support 30 fixed to the ball screw nut 90 are moved back and forth . As a result, the screw 23 to be driven can be moved back and forth.

The position detector 34 connected to the rear end of the output shaft 33 of the injection motor 29 detects the position of the screw 23 indicating the driving state of the screw 23 by detecting the rotation number or the rotation amount of the injection motor 29 . Between the movable support portion 24 and the support 30 is provided a load cell 35 for detecting a resin pressure as a pressure detecting device for detecting the pressure (reaction force) of the molten resin applied to the screw 23.

The injection apparatus 20 is provided with a plasticization moving apparatus 40 as a driving mechanism for driving the injection apparatus 20 to apply the nozzle touch pressure. The plasticizing and moving device 40 is composed of a plasticizing and moving drive part 91 and an injection device guide part 92. The injection apparatus guide section 92 is engaged with the movable support section 24, the support 30 and the front flange 93 constituting the injection apparatus 20. The injection apparatus 20 including the heating cylinder 21 can move horizontally on the frame 10 of the injection molding machine along the injection apparatus guide portion 92 while the plasticization movement drive portion 91 is driven. The injection apparatus 20 is advanced at a predetermined timing by driving the plasticization moving apparatus 40 described above so that the nozzle of the heating cylinder 21 is brought into contact with the stationary mold 53 to perform the nozzle touch.

The heating cylinder 21 is supported by a front flange 93. At the rear end of the front flange 93, there is provided a contact portion 5 functioning as a restriction means for restricting the advance or retreat of the screw 23.

The contact portion 5 is provided on the side of the heating cylinder 21 so that the tip end of the screw 23 comes into contact with a nozzle portion not shown which is provided in front of the heating cylinder 21 when the screw 23 is in the most advanced state, It is also a stopper to regulate. Thereby, at the stroke advancing limit of the screw 23, the abutting portion 5 comes into contact with the movable support portion 24. The reaction force of the total axial force exerted by the injection motor 29 is detected by the load pressure detecting load cell 35. [ The contact portion 5 is not necessarily provided at the rear end of the front flange 93 and the rear end of the heating cylinder 21 may be the contact portion 5. [

The weighing motor 25, the rotation detector 32, the injection motor 29, the position detector 34 and the load cell 35 for detecting the hydraulic pressure are connected to the control device 45. The detection signals output from the rotation detector 32, the position detector 34, and the load cell 35 are sent to the controller 45. [ The control device 45 controls the operations of the metering motor 25 and the injection motor 29 based on the detection signal. However, the control device 45 may be provided alone or may be provided as a part of a control unit that controls the entire injection molding machine.

The mold clamping apparatus 50 includes a fixed plate 54 as a stationary mold supporting apparatus fixed to a frame 10 and a base 54 provided movably with respect to the frame 10 at a predetermined distance between the fixed plate 54 And a toggle support 56 as a plate. The toggle support 56 functions as a toggle-type clamping device support device. A plurality of (for example, four) tie bars 55 as guide means extend between the fixed plate 54 and the toggle support 56.

The movable mold plate 52 functions as a movable mold holding apparatus provided so as to be opposed to the fixed mold plate 54 and movable back and forth along the tie bar 55 The movable mold plate 52 moves along the tie bar 55 to mold, mold, and mold.

The mold apparatus 70 comprises a stationary mold 53 and a movable mold 51. The stationary mold 53 is mounted on a mold mounting surface opposed to the movable mold plate 52 of the stationary mold plate 54. On the other hand, the movable mold 51 is mounted on the mold mounting surface opposed to the fixed mold plate 54 of the movable mold plate 52.

A toggle mechanism 57 as a toggle mold clamping device is mounted between the movable mold plate 52 and the toggle support 56. At the rear end of the toggle support 56, a mold clamping motor 46 as a mold clamping drive source for actuating the toggle mechanism 57 is provided. The mold-shaped motor 46 is provided with a motion direction changing device (not shown), which is composed of a ball screw mechanism or the like, for converting the rotational motion into a reciprocating motion. By moving the ball screw shaft 59 forward and backward The toggle mechanism 57 can be operated. Here, the mold-shaped motor 46 is preferably a servo motor and is provided with a mold opening / closing position sensor 47 as an encoder for detecting the number of revolutions. The control device 45 can calculate the positions of the movable mold 52 and the movable mold 51 through the rotational speed detected by the mold open / close position sensor 47. [

The toggle mechanism 57 can be operated by moving the crosshead 60 forward and backward by driving the mold body motor 46 as a driving section. In this case, when the crosshead 60 is advanced (moved in the right direction in the drawing), the movable plate 52, which is the driven portion, is advanced and closed. Then, a clamping force is generated by multiplying the driving force by the mold clamping motor 46 by the toggle magnification, and the mold clamping force is applied by the clamping force.

A metal member 61 is provided at the upper and lower ends of both sides of the fixed plate 54 in the mold clamping device 50 and the upper and lower ends of both sides of the movable plate 52, A mold auxiliary motor 62 is provided at a position corresponding to the installed position in which a shaft 63 capable of linear reciprocating motion is connected. At this time, the shaft (63) capable of linear reciprocating motion is provided with an electromagnet (64) at the tip end facing the metal member (61). The metal plate 61 and the mold auxiliary motor 62 are provided on both sides of the stationary plate 54 and the movable plate 52 but the present invention is not limited thereto, It may be provided inside the movable mold plate 52. In addition, in the mold clamping device 50, the electromagnet 64 and the mold clamping assist motor 62 are controlled by the control device 45. [ The shaft 63 may be a ball screw shaft and the mold auxiliary motor 62 may be a hollow motor having a ball screw nut therein. The shaft 63 is screwed to the ball screw nut of the mold auxiliary motor 62, which is a hollow motor, to constitute a motion direction changing mechanism for converting rotational motion into linear motion.

The metal member 61 and the electromagnet 64 are used in the mold closing operation of the mold clamping apparatus 50. [ The electromagnet 64 may be in the form of a coiled coil about an iron core. The mold clamping apparatus 50 moves the movable mold 52 in the injection pressure mode to maintain a constant gap before the fixed mold 53 and the movable mold 51 are brought into close contact with each other, The movable mold 51 and the stationary mold 53 are brought into close contact with each other. The metal member 61 and the electromagnet 64 are used when a fixed gap is maintained before the fixed mold 53 and the movable mold 51 are brought into close contact with each other. That is, when the fixed mold 53 and the movable mold 51 are kept in a constant gap before being brought into close contact with each other, the link of the toggle mechanism 57 is not entirely unfolded so that the movable mold plate 52 is pushed back . At this time, the electromagnet 64 is turned on by the control device 45 to generate attraction with the metal member 61, thereby suppressing the pushing back of the movable mold plate 52. [

The mold auxiliary motor 62 is used as a mold auxiliary driving unit to adjust the distance between the electromagnet 64 provided at the tip of the shaft 63 and the metal member 61 provided in the stationary mold 53. That is, when the fixed mold 53 and the movable mold 51 hold a constant gap for a predetermined period of time before touching in the injection compression mode, the mold auxiliary motor 62 causes attraction between the electromagnet 64 and the metal member 61 The distance between the electromagnet 64 and the metal member 61 is adjusted. This gap is adjusted by the linear reciprocating motion of the shaft 63 in accordance with the operation of the mold auxiliary motor 62.

Specifically, the control device 45 controls the thickness of the molds 51 and 53, the length of the metal member 61, the length of the electromagnet 64 provided at the tip of the shaft 63, The length of the shaft 63 is set by using the gap information between the movable mold 51 and the mold auxiliary motor 62 to thereby move the shaft 63 forward or backward to set the length of the shaft 63 . Here, the length of the shaft 63 is set such that when the stationary mold 53 and the movable mold 51 reach a predetermined gap position in the injection compression mode, a force capable of maintaining the gap is applied to the electromagnet 64, Means a length of the shaft 63 protruding from the mold-clamping auxiliary motor 62 so as to occur between the metal member 61 and the metal member 61. For example, when the stationary mold 53 and the movable mold 51 reach a predetermined gap, the metal member 61 is brought into contact with the electromagnet 64 provided at the tip of the shaft 63, And the length of the protrusion 63 protruding from the mold-clamping auxiliary motor 62.

Fig. 2 is a detailed view of the mold clamping apparatus of Fig. 1, showing a mold-clamping state, and Fig. 3 is a partial perspective view of Fig. The operation of the mold clamping apparatus 50 will be described with reference to FIGS. 2 and 3. FIG.

First, the control device 45 receives the gap information before touching the stationary mold 53 and the movable mold 51 in the injection compression mode from the user. The control device 45 controls the thickness of the molds 51 and 53, the length of the metal member 61, the length of the electromagnet 64 provided at the tip of the shaft 63, The gap information between the electromagnet 64 and the metal member 61, and the attraction force in accordance with the distance between the electromagnet 64 and the metal member 61, is set. In other words, the control device 45 drives the mold clamping auxiliary motor 62 to move the shaft 63 forward or backward to set the length of the shaft 63. Here, the length of the shaft 63 is set such that when the stationary mold 53 and the movable mold 51 reach a predetermined gap position in the injection compression mode, a force capable of maintaining the gap is applied to the electromagnet 64, Means a length of the shaft 63 protruding from the mold-clamping auxiliary motor 62 so as to occur between the metal member 61 and the metal member 61. For example, when the stationary mold 53 and the movable mold 51 reach a predetermined gap, the metal member 61 is brought into contact with the electromagnet 64 provided at the tip of the shaft 63, And the length of the protrusion 63 protruding from the mold-clamping auxiliary motor 62.

Then, the mold clamping device 50, which has been opened, performs a mold closing operation under the control of the control device 45. Refers to retracting the movable mold plate 52 provided with the movable mold 51 to move the movable mold 51 away from the stationary mold 53. [ "Molding" means that the movable mold 52 is moved in the direction of the fixed mold plate 54 in a state where the movable mold 51 is separated from the stationary mold 53 so that the parting face of the movable mold 51 is fixed to the stationary mold The movable mold 51 is brought close to the stationary mold 53 in a state where the movable mold 51 is in contact with the parting face of the stationary mold 53. [ In this state, the first mold clamping force is set as the mold clamping force. When the crosshead 60 is driven by the mold body motor 46 which is a driving section, the toggle mechanism 57 is opened so that the toggle link is unfolded.

When the movable mold 51 and the fixed mold 53 reach the position of the gap set by the user, the mold clamping apparatus 50 maintains the mold clamping force and the molds 51 and 53 ). At this time, the electromagnet 64 is turned on under the control of the controller 45. Attraction is generated between the electromagnet 64 and the metal member 61 as the electromagnet 64 is turned on so that the movable plate 52 is prevented from being pushed back by the injection pressure of the resin.

When a predetermined amount of resin is filled in the mold in a state in which the constant gap between the movable mold 51 and the stationary mold 53 is maintained, the mold clamping apparatus 50 performs the mold clamping operation. The term " shape " means that the stationary mold 53 is in contact with the movable mold 51 by applying further force to the movable mold 51. [ In this state, a second mold clamping force larger than the first mold clamping force is set as the mold clamping force, and the mold clamping operation is performed at a speed lower than the mold clamping speed. If the electromagnet 64 and the metal member 61 are in contact with each other while maintaining the predetermined gap, the movable mold 51 and the stationary mold 53 are not in contact with each other, that is, before the second mold clamping force is generated , The control device 45 turns off the electromagnet 64 and drives the mold clamping auxiliary motor 62 to retract the shaft 63 in the direction opposite to the metal member 61 by the gap or more, The second mold clamping force can be generated by bringing the mold 51 and the fixed mold 53 into complete contact with each other. That is, if the movable mold 51 and the stationary mold 53 are brought into close contact with each other while the electromagnet 64 and the metal member 61 are in contact with each other, the electromagnet 64 and the metal member 61 may be damaged. The electromagnet 64 is turned off and the electromagnet 64 is retracted by the gap or more so that the movable mold 51 and the stationary mold 53 are brought into contact with each other before the movable mold 51 and the stationary mold 53 are brought into close contact with each other, So that the electromagnet 64 and the metal member 61 do not come into contact with each other.

After the injection operation is completed, the mold clamping apparatus 50 performs the above-described mold opening operation. When the crosshead 60 is pulled backward by driving the mold body motor 46 as a driving unit, the toggle link of the toggle mechanism 57 is folded and the mold opening operation is performed. Whereby the injection-molded product is taken out.

Fig. 4 is a cross-sectional view of the mold auxiliary motor and the shaft of Fig. 3; 4, the mold auxiliary motor 62 includes a stator 92 fixed to the motor frame 91 and a rotor 93 provided on the inner circumferential side of the stator 92. As shown in Fig. The rotor (93) is rotatably supported with respect to the motor frame (91). For this purpose, a hollow rotor shaft 94 is fitted and fixed to the rotor 93. Both ends of the rotor shaft 94 are supported by the motor frame 91 by the bearings 95. A ball screw nut is fixed in the rotor shaft 94. The ball screw shaft 63 is screwed with a ball screw nut fixed to the rotor shaft 94 to convert the rotational motion into a linear motion and reciprocate. When the mold auxiliary motor 62 is driven, the hollow rotor shaft 94 rotates. The rotation of the rotor shaft 94 is transmitted to the ball screw nut and the rotation of the ball screw nut is transmitted to the ball screw shaft 63 so that the ball screw shaft 63 is moved forward or backward.

5 is a flowchart illustrating a control method of an injection molding machine according to an embodiment of the present invention.

Referring to FIG. 5, first, the controller 45 receives gap information between the fixed mold 53 and the movable mold 51 in the injection compression mode of the injection molding machine from the user (S501). The gap is, for example, between 0.1 mm and 0.5 mm.

The control device 45 receiving the gap information sets the length of the shaft 63 by driving the mold auxiliary motor 62 (S502). Specifically, the control device 45 controls the thickness of the mold 51, the length of the metal member 61, the length of the electromagnet 64 provided at the tip of the shaft 63, the length of the fixed mold 53 in the injection compression mode, And the length of the shaft 63 is set by using the gap information between the movable mold 51 and the movable mold 51. The control device 45 drives the mold clamping auxiliary motor 62 to advance or retreat the shaft 63 to set the length of the shaft 63. [ Here, the length of the shaft 63 is set such that when the stationary mold 53 and the movable mold 51 reach a predetermined gap position in the injection compression mode, a force capable of maintaining the gap is applied to the electromagnet 64, Means a length of the shaft 63 protruding from the mold-clamping auxiliary motor 62 so as to occur between the metal member 61 and the metal member 61. For example, when the stationary mold 53 and the movable mold 51 reach a predetermined gap, the metal member 61 is brought into contact with the electromagnet 64 provided at the tip of the shaft 63, And the length of the protrusion 63 protruding from the mold-clamping auxiliary motor 62.

Next, the controller 45 drives the mold-clamping motor 46 to drive the mold-closing operation for moving the movable mold 52 toward the fixed mold 54 (S503). That is, the control unit 45 pushes the crosshead 60 by the mold-shaped motor 46, and the toggle mechanism 57 is unfolded with the toggle link unfolded.

The control device 45 checks the gap between the movable mold 51 and the fixed mold 53 while moving the movable mold 52 toward the fixed mold 54 and determines whether the gap reaches the gap set in step S501 (S504). That is, it is confirmed whether the positions of the movable mold 51 and the fixed mold 53 reach the position of the gap. When the gap between the movable mold 51 and the fixed mold 53 reaches the gap set in the step S501, the control device 45 controls the electromagnet 64 provided at the tip of the shaft 63 of the mold- (S505). Attraction is generated between the electromagnet 64 and the metal member 61 as the electromagnet 64 is turned on so that the movable plate 52 is prevented from being pushed back by the injection pressure of the resin.

The control device 45 drives the metering motor 25 to inject the molten resin into the cavities in the molds 51 and 53 (S506). The control device 45 drives the mold clamping motor 46 to move the movable mold 52 in the direction of the fixed mold 54 to fix the movable mold 51 to the fixed mold 54. When the mold is filled with the molten resin, The mold 53 is closely contacted (S507, S508). The mold clamping apparatus 50 performs the mold clamping operation when the molten resin is filled in the mold by a predetermined amount while maintaining a constant gap between the movable mold 51 and the stationary mold 53. [ The term " shape " means that the stationary mold 53 is in contact with the movable mold 51 by applying further force to the movable mold 51. [ In this state, the mold clamping force is set to be greater than the mold clamping force when the above-described constant gap is maintained, and the mold clamping operation is performed at a speed lower than the mold clamping speed. If the electromagnet 64 and the metal member 61 are in contact with each other while maintaining the predetermined gap, the movable mold 51 and the stationary mold 53 are not in contact with each other, that is, before the second mold clamping force is generated , The control device 45 turns off the electromagnet 64 and drives the mold clamping auxiliary motor 62 to retract the shaft 63 in the direction opposite to the metal member 61 by the gap or more, The second mold clamping force can be generated by bringing the mold 51 and the fixed mold 53 into complete contact with each other. That is, if the movable mold 51 and the stationary mold 53 are brought into close contact with each other while the electromagnet 64 and the metal member 61 are in contact with each other, the electromagnet 64 and the metal member 61 may be damaged. The electromagnet 64 is turned off and the electromagnet 64 is retracted by the gap or more so that the movable mold 51 and the stationary mold 53 are brought into contact with each other before the movable mold 51 and the stationary mold 53 are brought into close contact with each other, So that the electromagnet 64 and the metal member 61 do not come into contact with each other.

After the movable mold 51 and the stationary mold 53 are in close contact with each other, the controller 45 drives the metering motor 25 to complete the filling of the remaining space of the cavities in the molds 51 and 53 with the molten resin, And the injection molding operation is performed after the injection molded article is taken out (S509). The mold opening operation is a process of retracting the movable mold plate 52.

While the specification contains many features, such features should not be construed as limiting the scope of the invention or the scope of the claims. In addition, the features described in the individual embodiments herein may be combined and implemented in a single embodiment. Conversely, various features described in the singular < Desc / Clms Page number 5 > embodiments herein may be implemented in various embodiments individually or in combination as appropriate.

Although the operations have been described in a particular order in the figures, it should be understood that such operations are performed in a particular order as shown, or that all described operations are performed to obtain a sequence of sequential orders, or a desired result .

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. The present invention is not limited to the drawings.

52: movable template
54: Fixed plate
51: Operation mold
53: Fixed mold
61: metal member
62: Shape Auxiliary Motor
63: Axis
64: Electromagnet

Claims (13)

A fixed plate on which a stationary mold is mounted;
A movable plate disposed to face the stationary plate and mounted with a movable mold facing the stationary mold, the movable plate being moved by a toggle mechanism;
A metal member mounted on at least one side surface of the fixed plate;
An electromagnet mounted on at least one side of the movable plate opposite to the metal member; And
A control device controlling the toggle mechanism to move the movable mold in the direction of the fixed mold to perform the injection compression mode, and to maintain the gap by turning on the electromagnet when forming a gap between the movable mold and the stationary mold; . The method according to claim 1,
And a mold auxiliary driving unit having a shaft to which the electromagnet is attached at its tip and which is capable of linear reciprocating motion,
Wherein the control unit controls the mold clamping sub-driver to linearly move the shaft so that a force for holding the gap is generated between the electromagnet and the metal member. 3. The method of claim 2,
The control device includes:
And controls the mold clamping sub-driver to linearly move the shaft so that the electromagnet and the metal member contact each other when the gap is formed. The method of claim 3,
The control device includes:
Wherein when the resin is filled with a predetermined amount of the cavity between the stationary mold and the movable mold, the movable mold moves so that the stationary mold and the movable mold come into close contact with each other. 5. The method of claim 4,
The control device includes:
The stationary mold and the movable mold after the turn-off, the electromagnet prior to the close contact with the injection molding machine, characterized in that the retraction to the electromagnet to control the mold clamping auxiliary drive in the opposite direction of the metal member as long as the gap above. 6. The method according to any one of claims 2 to 5,
The mold sub-
A ball screw nut is provided on the inside of the rotor as a motor in which a hollow is formed,
Wherein the shaft is a ball screw shaft corresponding to the ball screw nut and inserted into the hollow to perform a linear motion when the rotor rotates. 6. The method according to any one of claims 1 to 5,
Wherein the metal member is installed at upper and lower ends of both side surfaces of the fixed plate,
Wherein the electromagnets are installed at upper and lower ends of both side surfaces of the movable mold plate. 6. The method according to any one of claims 1 to 5,
Wherein the gap is 0.1 mm to 0.5 mm. A control method of an injection compression mode of an injection molding machine, comprising a mold clamping device including a toggle mechanism for moving a movable mold plate on which a movable mold is mounted to and from a fixed mold plate on which a fixed mold is mounted,
Setting a gap between the movable mold and the fixed mold in an injection compression mode;
Controlling the toggle mechanism to move the movable plate in the direction of the fixed plate and determining whether the movable mold has reached a position spaced from the stationary mold by the gap; And
And holding the gap by turning on an electromagnet mounted on at least one side of the movable plate against a metal member mounted on at least one side of the fixed plate. 10. The method of claim 9,
Wherein the electromagnet is installed on a shaft which is opposed to the metal member and is capable of linear reciprocating motion,
Wherein the step of setting the gap includes the step of linearly moving the shaft so that attraction force for holding the gap between the electromagnet and the metal member is generated. 11. The method of claim 10,
Filling the cavity between the stationary mold and the movable mold with resin; And
Further comprising: moving the movable plate when the resin is charged to a predetermined amount of the cavity so that the fixed mold and the movable mold are closely contacted with each other. 12. The method of claim 11,
The method of claim 1,
And withdrawing the shaft in a direction opposite to the metal member by more than the gap after the electromagnet is turned off before the fixed mold and the movable mold are brought into close contact with each other. 13. The method according to any one of claims 10 to 12,
Wherein the shaft is a ball screw shaft which is inserted into the hollow of a motor having a hollow and provided with a ball screw nut on the inner side of the rotor so as to perform linear motion when the rotor rotates.

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