JP2010099913A - Mold clamping method and mold clamping device for injection molding machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve a problem wherein some kinds of labels are bent in the midway of push-in, by getting inferior against a suction force, to form a defective, when the label is pushed in up to a fixed position using a mold closing operation, after positioning the label by inserting the label into a molding die and sucking the label onto a cavity side face, in an injection molding machine for in-mold labeling molding. <P>SOLUTION: In a mold clamping method for the injection molding machine, the label 61 is firmly fixed onto the cavity face and prevented from dropping down at the time point when the label is inserted, by providing a pressure regulating means for suction pressure, as a separate circuit, in a suction circuit of the label, and is moved smoothly when sliding-moved, and thus it is prevented a molding from getting defective so that a nondefective rate is enhanced. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a mold clamping method and a mold clamping apparatus of an injection molding machine for molding an in-mold labeling container.

  Conventionally, in injection molding, resin melt-plasticized in a heating cylinder is injected and filled into a mold cavity that is attached to a mold clamping device and fully closed, and then cooled and solidified to take out a molded product. A molding method and a molding apparatus (see, for example, Patent Documents 1 and 2) for molding an in-mold labeling container using a mold clamping device, a mold device, a plasticizing device, an injection device, a control device, and a label supply device are known.

  FIG. 5 is a schematic view of a mold clamping device of a conventional injection molding machine disclosed in Patent Document 1, and FIG. 6 is a schematic plan view showing a mold clamping part and a mold part of a conventional injection molding machine disclosed in Patent Document 2. FIG. 7 and FIG. 7 are explanatory diagrams showing a conventional molding sequence. The mold clamping method and mold clamping apparatus of an injection molding machine for molding an in-mold labeling container will be briefly described with reference to these drawings.

  In FIG. 5, the mold clamping device 10 is arranged to be movable with respect to the frame 17 with a predetermined distance between the frame 17, the fixed platen 12 fixed to the frame 17, and the fixed platen 12. And a toggle support 15.

  A plurality (for example, four) of tie bars 16 extend between the fixed platen 12 and the toggle support 15.

  The movable platen 13 is disposed so as to face the fixed platen 12 and can move forward and backward along the tie bar 16 (in the horizontal direction in the figure).

  The mold apparatus 40 includes a fixed mold 41 and a movable mold 42, and the fixed mold 41 is on a mold mounting surface facing the movable platen 13 of the fixed platen 12, and the movable mold 42 is the movable platen 13. The fixed platen 12 is attached to a die mounting surface facing the fixed platen 12.

  An ejector device (not shown) for projecting a molded product may be attached to the rear end (left end in the figure) of the movable platen 13.

  A toggle mechanism 20 is disposed between the movable platen 13 and the toggle support 15, and a mold clamping motor 26 that operates the toggle mechanism 20 is disposed at the rear end of the toggle support 15.

  The mold clamping motor 26 includes a motion direction conversion mechanism (not shown) including a ball screw mechanism that converts rotational motion into reciprocating motion, and the toggle mechanism 20 is moved forward and backward (left and right in the drawing). And an encoder 27 for detecting the rotational speed is provided as a mold opening / closing position sensor.

  The toggle mechanism 20 includes a cross head 24 attached to the drive shaft 25, a second toggle lever 23 attached to the cross head 24 so as to be able to swing, a first toggle lever 21 attached to the toggle support 15 so as to be swingable, and And a toggle arm 22 that is swingably attached to the movable platen 13.

  The first toggle lever 21 and the second toggle lever 23 and the first toggle lever 21 and the toggle arm 22 are linked with each other.

  Therefore, when the mold clamping motor 26 is driven to advance the cross head 24 (rightward in the figure), the movable platen 13 is advanced and the mold is closed, and the position of the movable platen 13 at that time is controlled by the encoder 27. ing.

  A mold thickness adjusting device 35 is disposed at the rear end (left end in the figure) of the toggle support 15 in order to adjust the position of the toggle support 15 with respect to the fixed platen 12.

  The toggle support 15 is formed with a tie bar insertion hole (not shown), and the left end of the tie bar 16 in the figure is inserted into each tie bar insertion hole. The right end of the tie bar 16 is fixed to the fixed platen 12 by a fixing nut 16a.

  The tie bar 16 has a screw portion 36 formed with a screw on the outer periphery of the left end, and an adjustment nut 37 is screwed into the screw portion 36 of each tie bar 16.

  The adjustment nut 37 is attached to the rear end of the toggle support 15 so as to be rotatable and immovable in the axial direction of the tie bar 16. A driven gear 37 a is attached to the outer periphery of the adjustment nut 37.

  A mold thickness adjusting motor 31 is disposed at an upper portion of the rear end of the toggle support 15, and a driving gear 33 is attached to a rotation shaft of the mold thickness adjusting motor 31.

  A conductive member 34 such as a chain or a toothed belt is attached around the driven gear 37 a and the driving gear 33 of the adjustment nut 37.

  Therefore, when the mold thickness adjusting motor 31 is driven and the driving gear 33 is rotated, the adjusting nut 37 screwed into the threaded portion 36 of each tie bar 16 is rotated in synchronization with the mold thickness adjusting motor 31. The toggle support 15 can be moved back and forth by a predetermined distance by rotating 31 in a predetermined direction by a predetermined rotation speed, and an encoder 32 for detecting the rotation speed is provided as a mold clamping position sensor.

  A mold clamping force sensor 18 is disposed on one of the tie bars 16, and the mold clamping force applied to the mold apparatus 40 can be known by detecting the extension amount of the tie bar 16.

  The mold clamping force sensor 18, the encoder 27, the mold clamping motor 26, the encoder 32, and the mold thickness adjusting motor 31 are connected to the control device 19, and the control device 19 outputs detection signals output from the encoders 27 and 32. Based on this, the operations of the mold clamping motor 26 and the mold thickness adjusting motor 31 are controlled.

Here, the operation of the mold clamping apparatus during normal molding will be described.
When the mold clamping motor 26 is driven in the forward direction, the drive shaft 25 rotates in the forward direction, and the drive shaft 25 moves forward (rightward in the figure). Thereby, when the cross head 24 moves forward and the toggle mechanism 20 operates, the movable platen 13 moves forward.

  When the movable mold 42 attached to the movable platen 13 comes into contact with the fixed mold 41 (mold closed state), the mold clamping process is started. In the mold clamping process, a mold clamping force is generated in the mold apparatus 40 by the toggle mechanism 20 by further driving the mold clamping motor 26 in the forward direction. Thereafter, the molten resin is filled into the cavity space formed in the mold apparatus 40 by an injection apparatus (not shown).

  When performing mold opening, when the mold clamping motor 26 is driven in the reverse direction, the drive shaft 24 is retracted, the toggle mechanism 20 is operated, and the movable platen 13 is retracted.

  When the mold opening process is completed, an ejector (not shown) is operated, and the molded product in the movable mold 42 is ejected from the movable mold 42.

  In FIG. 6, the mold clamping device 10, the stationary platen 12, the movable platen 13, and the movable mold 42 are the same as those in FIG.

  The fixed mold 41 is detachably attached to the fixed platen 12 of the mold clamping device 10, and a cavity side surface 52 that forms the outer shape of the in-mold labeling container is engraved at the center along the axis L1 of the injection molding machine. Yes. A two-dot chain line in the cavity side surface 52 indicates the inserted label 61.

  Between the cavity side surface 52 and the outer wall of the fixed mold 41, a passage 46 for intake air is penetrated, and a casing 45 is disposed so as to cover the passage 46, so that the passage 46 and the atmosphere are kept airtight. The casing 45 is connected to the intake means 71 via the vacuum valve 72.

  When the vacuum valve 72 is ON, the suction means 71 and the casing 45 are connected, and when the vacuum valve 72 is OFF, the circuit on the suction means 71 side is turned OFF, and the circuit on the casing 45 side is opened to the atmosphere.

The movable mold 42 includes a base part 43 and a core part 44 attached and fixed to the base part 43, and the core part 44 enters the fixed mold 41 when the mold is closed.
Reference numeral 1 denotes an injection device for injecting molten resin into a mold.
The pressing sequence of the label 61 will be described later.

7, the fixed mold 41, the core portion 44, the passage 46, the cavity side surface 52, the label 61, the suction means 71, and the vacuum valve 72 are the same as those in FIG.
The end surface 48 is a contact surface on which the fixed mold 41 and the core portion 44 come into contact with each other when the mold is fully closed, and the end surface 49 is a surface carved from the end surface 48 by one step.

  The end surface 51 is on the side opposite to the end surface 48 and is an end surface that forms the bottom surface of the foot portion of the molded product. The resin filling port 53 is a filling port that is opened in the shaft core portion of the fixed mold 41 and is filled with molten resin from the injection device 1.

  The end surface 54 of the core portion 44 is a contact surface that is positioned by contact between the fixed die 41 and the core portion 44 when the die is fully closed, and the end surface 55 is a surface carved from the end surface 54 by one step. It is an end surface which forms the upper surface of the flange part of goods.

Next, the pressing sequence of the label 61 in the above configuration will be described.
The label 61 is inserted into the fixed mold 41. In advance, the vacuum valve 72 is turned on, and the passage 46 communicates with the intake means 71 to suck in the passage 46. In this state, the mold is closed, and the core portion 44 enters the fixed mold 41 (FIG. 7G).

  While the mold closing proceeds, the vacuum valve 72 remains connected to the intake means 71 so that the label 61 does not fall. Therefore, depending on the type and strength of the label 61, the end face 55 of the core portion 44 comes into contact with the label 61, and even if the label 61 is to be pushed in, the suction force of the suction means 71 is stronger and the label 61 can be pushed in. There is a problem that it cannot be bent at the end surface 55 of the core portion 44 (FIG. 7H).

  However, the mold is clamped while it is bent, and after completion of the mold clamping, the molten resin is filled from the resin filling port 53. After completion of cooling, the mold is opened, the molded product is taken out at the mold opening limit position, and the next label 61 is inserted. This operation is sequentially repeated at regular intervals to continuously form the in-mold labeling container.

  When the end surface 48 of the fixed mold 41 and the end surface 54 of the core portion 44 come into contact with each other and the mold closing is completed, the space including the label 61 formed between the fixed mold 41 and the core portion 44 is in-mold. The outer shape of the container in the labeling container molding.

WO2006 / 098321 Japanese Patent Laid-Open No. 5-285981

  In vacuum molding type in-mold labeling container molding in which paper or film constituting the surface of the container is inserted into the mold in advance and molded, the label material is paper, plastic film, aluminum film according to market demand A wide variety of things have come to be used. Along with this, the label strength is also varied, and there are labels with low waist strength.

  Labels with low waist strength often do not fit neatly into the cavity. In this case, the outer end portion of the label sticks to the side surface of the cavity while protruding from the cavity, and the mold is closed in that state. For this reason, the suction force of the air intake means remains at the time of label suction, and the label is forced to be pushed in by the end surface of the core part. As a result, the label cannot be pushed in, and the end face part of the core part There was a problem of bending (FIG. 7H).

  Therefore, the present invention solves this conventional problem, and even in the case of a label with low waist strength, the in-mold can be pushed in while sliding the label to the final position in the mold by the mold closing operation. An object of the present invention is to provide a mold clamping method and a mold clamping apparatus for an injection molding machine for forming a labeling container.

  Therefore, in the mold-clamping method of in-mold label container molding in which injection molding is performed after the label is mounted on the fixed mold in advance, the label is mounted on the side of the cavity of the fixed mold before the mold closing starts, and the fixed mold after the mold closing starts The label is pressed while sliding with a movable mold in a state where the label mounting force is weakened, and the label is attached to the side of the cavity of the fixed mold by the suction force from the fixed mold. The tightening method was assumed.

  Further, the clamping method is such that the label mounting force is weakened between the start of retracting the pseudo core and the time when the outer end surface of the label comes into contact with the movable mold.

  The suction circuit for the label mounted on the side surface of the cavity of the fixed mold is assumed to have a suction pressure regulating means, and this pressure regulating means comes into contact with the movable mold at the outer end face of the label from the start of the withdrawal of the pseudo core. In the first embodiment, the suction pressure adjusting means is arranged on a circuit branched from the circuit connecting the intake means and the fixed mold. In the second embodiment, the suction pressure is adjusted. The pressure regulating means was a mold clamping device arranged in series on a circuit connecting the intake means and the fixed mold. The suction pressure adjusting means is a throttle valve.

  When the label is mounted on the side of the cavity in the fixed mold before mold closing starts, it is moved by sliding during the mold closing process to prevent displacement from the label mounting position and to prevent dropping from the mold. Since the label can be mounted with an increased suction force without considering the above, there is no label displacement or dropping, and the yield rate of molded products is improved.

  When the label is moved by sliding during the mold closing process, the pressure adjustment means for adjusting the suction pressure by adjusting the opening of the throttle valve is installed in the label suction circuit, so even if the label is weak, it will not break. Therefore, it is possible to prevent defective molded products and improve the yield rate of molded products.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
1 is a schematic plan view and sequence diagram showing a mold clamping unit, a mold unit and a label supply unit of an injection molding machine showing Embodiment 1 of the present invention, FIG. 2 is a suction pneumatic circuit and a molding sequence diagram, FIG. FIG. 4 is a schematic plan view of a mold clamping part and a mold part of an injection molding machine showing Example 2 of the present invention, and FIG. 4 is a schematic plan view of a mold part showing Example 3 of the present invention.

A first embodiment of the present invention will be described with reference to FIGS.
In FIG. 1, the upper diagram shows a schematic plan view of the mold clamping unit, the mold unit, and the label supply unit, and the lower diagram shows a sequence diagram. The injection device 1, the mold clamping device 10, the fixed platen 12, the movable platen 13, the fixed mold 41, the movable mold 42, the base portion 43, the core portion 44, the casing 45, the passage 46, the cavity side surface 52, the label 61, The intake means 71 is the same as that shown in FIG.

  Reference numeral 60 denotes a part of a first supply device that supplies a predetermined label 61 by suction from a known label feeder (not shown). A suction cup 66 is disposed at the tip of the arm 67. It is connected to the intake means 71 through a switching valve 81.

  When the switching valve 81 is ON, the suction means 71 and the suction cup 66 are connected, and when the switching valve 81 is OFF, the circuit on the suction means 71 side is turned OFF and the circuit on the suction cup 66 side is opened to the atmosphere.

  Reference numeral 64 denotes a second supply device, which includes a pseudo core 62 and an arm 65 to which the pseudo core 62 is attached. The arm 65 extends from the receiving position of the label 61 indicated by a solid line with the second supply device axis L2 as a rotation center. While turning upward to the position of the injection molding machine axis L1 indicated by the two-dot chain line, it can move horizontally from here to the feeding position indicated by the one-dot chain line, that is, the position inserted into the cavity side surface 52 of the fixed mold 41. Yes.

  The pseudo core 62 is used for winding and holding the label 61 supplied from the first supply device 60 around the outer periphery by suction and supplying the label 61 to the cavity side surface 52 of the fixed mold 41 of the injection molding machine. A large number of intake / exhaust passages 63 that are formed in a cup shape in cross-section and communicate with the hollow portion to the atmosphere are formed in the peripheral wall, and are connected to the intake means 71 and the air supply means 70 via the switching valve 80.

  When the switching valve 80 is ON, the pseudo core 62 is selectively connected to the intake means 71 and the air supply means 70, and when OFF, the pseudo core 62 is connected to the intake means 70 and the air supply means 77. OFF.

  The casing 45 is connected to the intake means 71 via the vacuum valve 73. The vacuum valve 73 connects the intake means 71 and the casing 45 when ON, and closes the connection when OFF.

  Reference numeral 74 denotes an exhaust valve, which connects the casing 45 and a throttle valve 75 as pressure regulating means when ON, and disconnects from the throttle valve 75 when OFF.

Next, the label supply procedure of the above configuration will be described.
The switching valve 81 is turned on to connect the suction cup 66 and the suction means 71, and the label 61 is sucked from a well-known label feeder, and then the label 61 is put on standby at the transfer position shown in the figure. At this point, the pseudo core 62 is in the receiving position indicated by the solid line.

  The switching valve 81 is turned OFF to switch to the atmosphere side, and the switching valve 80 is switched to the intake means 71 side. As a result, the label 61 is attracted to the outer periphery of the pseudo core 62 and is finally wound around the outer periphery of the pseudo core 62.

  Next, the arm 65 turns upward about the second supply device axis L2 toward the position indicated by the two-dot chain line, and moves the pseudo core 62 to the position of the injection molding machine axis L1. At this time, the arm 67 of the first supply device 60 returns to the label supply position of the label feeder.

  When the pseudo core 62 reaches the position on the injection molding machine axis L1, the arm 65 moves horizontally to the position indicated by the alternate long and short dash line (left side in the figure), and the fixed mold in which the pseudo core 62 is opened. It is inserted into 41 and positioned at the delivery position.

  The switching valve 80 is switched to the air supply means 70 side, and high-pressure air is sent into the pseudo core 62. The high-pressure air is exhausted from the intake / exhaust passage 63, and the label 61 is supplied to the cavity side surface 52 on the inner surface of the fixed mold 41 by the exhaust pressure at this time.

  If the vacuum valve 72 is turned on and switched to the intake means 71 side, the label 61 supplied from the pseudo core 62 is attracted and held on the cavity side surface 52 in the fixed mold 41. After supplying the label 61, the arm 65 and the pseudo core 62 are horizontally moved to a position indicated by a two-dot chain line. As a result, the label 61 remains on the cavity side surface 52 in the fixed mold 41.

  Thereafter, the arm 65 reversely operates and returns to the receiving position for receiving the label 61 from the first supply device 60.

  When the fixed mold 41 and the movable mold 42 are fully closed and the mold clamping is completed, the molten resin is injected and filled into the cavity space in the mold by the injection apparatus 1, and the mold is opened when the cooling process is completed. The molded product is taken out and the next label 61 is inserted at the fully opened position of the mold.

  In the lower figure, the uppermost stage shows the position of the movable platen 13, the mold fully open is the fully opened position of the movable platen, the mold fully closed is the fully closed position of the movable platen, and the high / low switching is for adjusting the suction circuit pressure. The position where the vacuum valve 73 and the exhaust valve 74 of FIG.

  The second and third stages are the ON and OFF states of the vacuum valve 73 and the exhaust valve 74, the fourth stage is the process of the mold clamping device 10, and the bottom stage is a state diagram of the molding sequence diagram. ing. Details of the sequence will be described later.

  In FIG. 2, the intake means 71, the vacuum valve 73, the exhaust valve 74, and the throttle valve 75 are the same as in FIG. 1, and the core portion 44, end face 54, end face 55, core side face 56, label 61, resin filling port 53, end face. 51, the stationary mold 41, the cavity side surface 52, the passage 46, the end surface 48, and the end surface 49 are the same as those in FIG.

  Next, a pressing sequence of the label 61 in the mold clamping device 10 will be described with reference to FIGS. In the suction pneumatic circuit of FIG. 2, the solid line indicates that the circuit is ON, and the broken line indicates that it is OFF.

  At the start of a new cycle, the vacuum valve 73 is turned on, the exhaust valve 74 is turned off, and the suction means 71 sucks the passage 46 of the fixed mold 41 with a high vacuum pressure.

  The label 61 inserted into the fixed mold 41 is sucked and attached to the cavity side surface 52 with high vacuum pressure, and one end of the label 61 is positioned on the cavity side surface 52 in a state of protruding to the core portion 44 side.

  Subsequently, retraction of the pseudo core 62 is started, and when the pseudo core 62 is retracted from the open / close region of the movable mold 42, the mold clamping process is started. Then, the mold closing process proceeds with one end of the label 61 protruding to the core 44 side, and the core 44 enters the fixed mold 41 (FIG. 2A).

  When the mold closing process further proceeds, the end surface 55 of the core portion 44 comes into contact with the label 61. A high / low switching position is set at a position just before this contact, and when the movable platen 13 reaches this position, the vacuum valve 73 is turned off and the exhaust is exhausted. The valve 74 is turned ON, and the vacuum pressure in the passage 46 adsorbing the label 61 communicates with the atmosphere via the throttle valve 74.

  At this time, by properly adjusting the opening degree of the throttle valve 75 for each type of the label 61, the attracting force of the label 61 is also weakened, and the label 61 is pushed by the end surface 55 of the core portion 44 without being bent halfway. It is pushed in while sliding along (Fig. 2B).

  Further, when the label 61 is pushed in and the end face 48 and the end face 54 are in contact with each other, the label 61 has one end in contact with the end face 55 and the other end in contact with the end face 51 that forms the bottom surface of the container foot. is doing. At this time, the states of the vacuum valve 73 and the exhaust valve 74 are the same as in FIG. 2B (FIG. 2C).

  When the pressure is increased after the mold is fully closed and the mold clamping is completed, the vacuum valve 73 is turned on, the exhaust valve 74 is turned off, and the intake means 71 again passes the passage 46 of the fixed mold 41 at a high vacuum pressure. The label 61 is adsorbed to the cavity side surface 52 at a high vacuum pressure.

  In this state, the filling process is performed, and the molten resin is filled from the resin filling port 53. Thereafter, the cooling process proceeds, and the molded container contracts with the progress of cooling, and is held on the core side surface 56 of the core portion 44.

  The mold is opened after cooling is completed. At this time, the vacuum valve 73 is turned off and the exhaust valve 74 is turned on, and the vacuum pressure in the passage 46 adsorbing the label 61 communicates with the atmosphere via the throttle valve 75 (FIG. 2D).

  When the movable platen 13 reaches the fully open position of the mold, the product removal process and the label insertion process by vacuum suction start. At this time, the vacuum valve 73 is turned on and the exhaust valve 74 is turned off, and the suction means 71 sucks in the passage 46 of the fixed mold 41 with a high vacuum pressure, and the newly inserted label 61 is placed on the cavity side surface 52. Adsorption positioning with high vacuum pressure.

  Thereafter, the pause process starts, and a new cycle starts when the pause process time is up. This operation is sequentially repeated at regular intervals to continuously form the in-mold labeling container.

  Here, when the label 61 does not fall from the cavity due to the tension of the label 61 itself, the suction force of the suction means 71 may be weakened in response to the start of withdrawal of the pseudo core 62. In this way, if the outer end surface of the label 61 is in contact with the core portion 44 of the movable mold 42 after the pseudo core 62 starts to be retracted, the suction force of the suction means 71 is weaker than when the label 61 is delivered. be able to.

  When the end surface 48 of the fixed mold 41 and the end surface 54 of the core portion 44 come into contact with each other and the mold closing is completed, the space including the label 61 formed between the fixed mold 41 and the core portion 44 is in-mold. The outer shape of the container in the labeling molding.

Next, a second embodiment will be described as a modification of the present invention.
In FIG. 3, this figure is a simplified type of the first embodiment, in which an intake means 71, a throttle valve 76 as a pressure adjusting means, and a casing 45 are arranged in series. The fixed mold 41, casing 45, passage 46, cavity side surface 52, label 61, and intake means 71 are the same as those in FIG.

  When the vacuum valve 72 is ON, the suction means 71 and the casing 45 are connected. When the vacuum valve 72 is OFF, the connection with the suction means 71 is disconnected, and the casing 45 side is opened to the atmosphere.

  The throttle valve 76 can adjust the suction pressure for adsorbing the label 61 to the cavity side surface 52 by adjusting the throttle opening degree for each type of the label 61.

Next, the pressing sequence of the label 61 in FIG. 3 will be described.
The label supply unit for inserting the label 61 into the fixed mold 41 is the same as that shown in FIG. 1 and will not be described. At the start of a new cycle, the throttle valve 76 is previously set so that the inserted label 61 does not fall. Further, the opening degree is adjusted so that movement by sliding is possible.

  The vacuum valve 72 is turned on, and the suction means 71 sucks the passage 46 of the fixed mold 41 with a vacuum pressure proportional to the opening degree of the throttle valve 76.

  The label 61 inserted into the fixed mold 41 is attracted to the cavity side surface 52, and one end thereof is positioned on the cavity side surface 52 in a state of protruding to the core portion 44 side as in FIG. 2A. Mold closing is performed in this state.

  As the mold closing progresses, the suction pressure is adjusted, so that the label 61 is pushed into the fixed mold 41 without being bent halfway.

  When the mold clamping pressurization is completed, the filling process is performed, the molten resin is filled, and then the cooling process proceeds. After the cooling process is completed, the mold is opened. At this time, the vacuum valve 72 is turned off, and the vacuum pressure in the passage 46 adsorbing the label 61 communicates with the atmosphere via the vacuum valve 72.

  Next, the product removal process and the label insertion process by vacuum suction start. At this time, the vacuum valve 72 is turned ON, and the suction means 71 sucks the inside of the passage 46 of the fixed mold 41 with a vacuum pressure proportional to the opening of the throttle valve 76, and the newly inserted label 61 is placed on the side surface of the cavity. 52 is positioned by suction.

  Thereafter, the pause process starts, and a new cycle starts when the pause process time is up. This operation is sequentially repeated at regular intervals to continuously form the in-mold labeling container.

Next, Example 3 will be described as a further modification of the present invention.
In FIG. 4, this figure shows that the structure of the base part 43 and the core part 44 constituting the movable mold 42 in FIG. 1 is different by one part. The fixed mold 41, the end surface 48, the end surface 49, the cavity side surface 52, and the label 61 are the same as those in FIG.

  The movable mold 42 includes a base part 90, a core part 91 attached and fixed to the base part 90, and an ejector ring 92 inserted into the outer peripheral part of the core part 91.

  The ejector ring 92 is attached to a plurality of ejector rods 93 (only one is shown) that can pass back and forth through the inside of the base portion 90 (only one is shown) by a mounting bolt 94 as a fastening means. It is processed so as to be in close contact with the outer peripheral taper portion of the core portion 91 when the mold is fully closed.

  An end surface 95 of the ejector ring 92 on the fixed mold 41 side is a contact surface that contacts and positions the fixed mold 41 when the mold is fully closed, and the end surface 96 is formed by a surface carved from the end surface 95 by one step. It is an end surface which forms the upper surface of the flange part of goods.

Next, a pressing sequence of the label 61 will be described.
The pneumatic suction circuit for the label 61 is the same as that shown in FIG.
Prior to mold closing, the ejector rod 93 is pulled back, and the end surface (left side in the figure) of the base portion 90 and the end surface (right side in the figure) of the ejector ring 92 are in contact with each other.

  2B, the end surface 96 of the ejector ring 92 is brought into contact with the label 61 so that the label 61 is pushed by the end surface 96 without being bent along the cavity side surface 52. And is pushed in while sliding (FIG. 4K).

  Thereafter, the same process proceeds to FIGS. 2C and 2D. When the mold is opened after the cooling process is completed, and the movable mold 42 reaches the fully opened position, the product removal process starts. That is, the ejector drive device is driven (not shown), and the ejector rod 93 moves forward in the protruding direction of the molded product (left side in the figure) to forcibly separate the molded product from the core portion 91 (FIG. 4L). . Thereafter, removal by vacuum suction is performed. At the same time, the label insertion process starts.

  Next, the pause process starts, and a new cycle starts when the pause process time is up. This operation is sequentially repeated at regular intervals to continuously form the in-mold labeling container.

  The configuration of the present invention is as described above, and by providing a suction pressure adjusting means in the label suction circuit, the label of any waist strength is initially subjected to high vacuum pressure from the inside of the mold. Can be moved from the set position by sliding in the mold smoothly with a low vacuum pressure, and defects caused by bending of the film can be prevented and the yield rate is improved.

Schematic plan view and sequence diagram showing a mold clamping part, a mold part and a label supply part showing Example 1 of the present invention Similarly suction pneumatic circuit and molding sequence diagram Schematic plan view of a mold clamping part and a mold part showing Example 2 of the present invention The schematic plan view of the metal mold | die part which shows Example 3 of this invention Schematic diagram of conventional injection molding machine clamping device Schematic plan view showing conventional mold clamping part and mold part Explanatory drawing showing a conventional molding sequence

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Clamping apparatus 64 2nd supply apparatus 12 Fixed platen 66 Suction cup 13 Movable platen 70 Air supply means 41 Fixed mold 71 Intake means 42 Movable mold 73 Vacuum valve 43 Base part 74 Exhaust valve 44 Core part 75 Throttle valve 45 Casing 80 Switching valve 46 Passage 81 Switching valve 52 Side of cavity L1 Injection molding machine axis 60 First supply device L2 Second supply device axis 61 Label 62 Pseudo core

Claims (8)

In a mold-clamping method for in-mold labeling container molding in which injection molding is performed after a label is mounted on a fixed mold in advance, the label is mounted on the side of the cavity of the fixed mold before the mold is closed, and the fixed mold is started after the mold is closed A mold clamping method for an injection molding machine, wherein the label is pushed while sliding with a movable mold in a state where the label mounting force from the cavity side surface of the mold is weakened.   2. The mold clamping method for an injection molding machine according to claim 1, wherein the label is attached to the side surface of the cavity by a suction force from the fixed mold.   2. The mold clamping method for an injection molding machine according to claim 1, wherein the mounting force of the label is weakened between the start of retracting the pseudo core and the time when the outer end surface of the label comes into contact with the movable mold. . In a mold clamping device for in-mold labeling container molding in which injection molding is performed after a label is mounted on a fixed mold in advance, the suction circuit for the label mounted on the side surface of the cavity of the fixed mold has a suction pressure regulating means. A mold clamping device for an injection molding machine. 5. The injection molding machine according to claim 4, wherein the suction pressure adjusting means adjusts the pressure between the start of retraction of the pseudo core and the outer end surface of the label coming into contact with the movable mold. Clamping device. The mold clamping device for an injection molding machine according to claim 4, wherein the suction pressure adjusting means is disposed on a circuit branched from a circuit connecting the intake means and the fixed mold.   5. The mold clamping apparatus for an injection molding machine according to claim 4, wherein the suction pressure adjusting means is arranged in series on a circuit connecting the intake means and the fixed mold. The mold clamping device for an injection molding machine according to claim 4, wherein the pressure adjusting means for the suction pressure is a throttle valve.

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