JP4866744B2 - Injection molding machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To shorten a molding cycle in an injection molding machine having a constitution where a molded product is attached so as to cover at the mold side mounted on a rotary table by the mold opening. <P>SOLUTION: When the rotary table falls within a range of a rotation angle corresponding to a predetermined amplitude of vibration before stopping of the rotation, an eject pin is advanced so as to insert into an eject pin insertion hole protrudingly provided from the retracted limit position to the rotary table. When it is recognized that the rotary table is transited to a static state, the eject pin is advanced so as to insert to the mold. <P>COPYRIGHT: (C)2008,JPO&amp;INPIT

Description

  The present invention relates to an injection molding machine having a rotary table mounted with a mold and driven to rotate intermittently by a predetermined angle, and in particular, an eject pin that can be inserted into a mold from the side opposite to the mold mounting surface of the rotary table. The present invention relates to an injection molding machine equipped with

  Two molds are mounted (attached) on the rotary table at intervals of 180 °, and the rotary table is intermittently rotated in the forward and reverse directions by 180 °, or four on the rotary table. A four-stage type injection molding machine in which dies are mounted at intervals of 90 ° and the rotary table is intermittently rotated in a fixed direction by 90 ° is well known.

  In such an injection molding machine, for example, two fixed molds are provided corresponding to the two movable molds mounted on the rotary table, and each of the pair of the movable mold and the fixed mold is provided. Two injection units are provided to correspond to each other, and each time the rotary table rotates 180 °, the combination of the movable side mold and the fixed side mold is changed alternately, and the two injection units perform injection simultaneously. A horizontal injection molding machine that can easily perform two-color molding without using a complicated mold structure having a moving core or the like is known. Alternatively, for example, a single movable side mold is provided for two fixed side molds mounted on a rotary table, and a single injection unit is provided, and one of the two fixed side molds is provided. By alternately facing the movable mold, injection is performed on the stage where the molds are opposed, and the other stage is configured to place and position the insert article on the fixed mold. There is also known a vertical injection molding machine that can perform insert molding efficiently.

  In addition, for example, four fixed-side molds are mounted on the rotary table at intervals of 90 °, and the rotary table is intermittently rotated by 90 ° in a certain direction, thereby allowing one of the four fixed-side molds to be It is made to stop at the position facing the movable mold that is only provided one by one, placing and positioning the insert article in the mold, injecting and filling the molten resin, and ejecting and ejecting the molded product. In addition, a four-stage type vertical injection molding machine is also known in which each is performed in separate stages to further shorten the molding cycle in insert molding.

  In the injection molding machine using the rotary table as described above, when the resin (molded product) solidified by opening the mold is attached to the mold side mounted on the rotary table, the mold on the rotary table is used. An eject pin (machine side eject pin) that can be inserted into the mold mounted on the rotary table is provided from the side opposite to the mold mounting surface, and the mold side eject member (for example, mold side eject) is provided by this eject pin. By pressing a die-side eject plate (with a pin implanted), a molded product attached to the die is projected (separated) from the die.

  FIG. 11 is a simplified cross-sectional view of a main part of a conventional injection molding machine using a rotary table, and FIG. 11 is a diagram for explaining a conventional molded product ejection method. In FIG. 11, 101 is a movable die plate that can move forward and backward relative to a fixed die plate (not shown), 102 is a rotary table that is rotatably mounted on the movable die plate 101, and 103 is attached to the rotary table 102. The movable die 104 (mounted) is driven forward and backward by the drive force of an unillustrated ejecting servomotor, and its tip side is located in the rotary table 102 and from the side opposite to the die mounting surface of the rotary table 101. An eject pin (machine side eject pin) that can be inserted into the movable side mold 104, 105 is a mold side eject plate that can be moved back and forth in the movable side mold 103, and 106 is a mold side eject plate. The implanted mold side eject pin 107 includes a mold side eject plate 105 and a mold side eject pin 106. Spring giving the bias behavior of the leftward direction shown, 108 is a molded article (solidified resin).

  In the configuration shown in FIG. 11, molten resin is injected and filled into the mold cavity, and after a predetermined cooling period, the mold is opened, and the movable die plate 101 is driven to move backward in the drawing to the left. The molded product (solidified resin) 108 is pulled away from a fixed mold (not shown), and the molded product 108 is attached only to the movable mold 103. After the mold opening is completed, after confirming that the rotary table 102 is rotated by a predetermined angle and the rotary table 102 completely stops rotating and is in a stationary state, the eject pin (machine side eject pin) ) 104 is driven forward to start the ejection process (ejection ejection process). Prior to the start of the ejecting process, the eject pin 104 is in a standby position with its tip end surface slightly retracted from the surface opposite to the mold mounting surface of the rotary table 101 (the eject pin 104 is shown by a solid line in the figure). From this state, the tip side of the eject pin 104 is projected into the movable mold 103 through the eject pin insertion hole 102a of the rotary table 102, so that the eject pin 104 is ejected into the mold side eject plate. 105 (the eject pin 104 in this state is shown by a two-dot chain line), whereby the mold side eject pin 106 integrated with the mold side eject plate 105 causes the molded product 108 to move to the movable side mold. 103 is protruded (separated).

  As described above, the ejection of the eject pin 104 is started after waiting for the rotary table 102 to settle, so that the eject pin 104 collides with the rotary table 102 to prevent the mechanism from being damaged. Because.

  As described above, the resin (molded product) 108 solidified by mold opening is configured to adhere to the mold side (the movable mold 103 side in the example of FIG. 11) mounted on the rotary table 102. In this injection molding machine, since the ejection process is started after waiting for the rotary table 102 to settle, it has been pointed out that this is a bottleneck for shortening the molding cycle. Further, the eject pin 104 is started to advance from a state in which the tip surface of the eject pin (machine side eject pin) 104 is slightly retracted from the surface opposite to the mold mounting surface of the rotary table 101. Therefore, the eject pin 104 It takes some time for the front end surface of 104 to pass through the turntable 102 (particularly when the turntable is composed of a thick disk-shaped table base and a mold mounting plate) This is an obstacle to shortening the molding cycle, because the time required for the tip surface to pass through the rotary table is not ridiculous).

  The present invention has been made in view of the above points. The object of the present invention is to provide an injection molding machine having a configuration in which a molded product is attached to a mold mounted on a rotary table by mold opening. To shorten it.

In order to achieve the above-described object, an injection molding machine according to the present invention includes a rotary table mounted with a mold and driven to rotate intermittently by a predetermined angle, a table servomotor for rotating the rotary table, and the rotary table. A first sensor for detecting a rotation amount of the rotary table, an eject pin that can be inserted into the mold from the side opposite to the mold mounting surface of the rotary table and can press the mold-side eject member, and the eject An eject servomotor that linearly drives the pin via a ball screw mechanism, a second sensor for detecting the amount of linear movement of the eject pin, and a controller that controls the operation of the injection molding machine,
When the controller monitors the output of the first sensor and recognizes that the rotary table has entered a rotation angle range corresponding to a predetermined vibration width range before the rotation stop, the servo motor for ejection Then, the eject pin is moved forward from the retreat limit position so as to enter the eject pin insertion hole formed in the rotary table, and when the rotary table transitions to a static state, the eject servo motor The eject pin is advanced so as to enter the mold.
Further, the eject pin insertion hole drilled in the rotary table is configured as an arc-shaped hole having an angular width corresponding to a rotational angle range corresponding to the predetermined vibration width range.
Further, when the eject pin is in the retreat limit position, the tip of the eject pin is positioned in an annular groove provided on the opposite side to the mold mounting surface of the rotary table.

In the present invention, when the rotary table enters a rotation angle range corresponding to a predetermined vibration width range (a vibration width range roughly corresponding to the damped vibration region) before the rotation stop, the eject pin is ejected from the retreat limit position to the rotary table. Since the ejecting process is started so as to enter the pin insertion hole, that is, immediately before the rotary table is settled, the molding cycle can be shortened accordingly. Here, for example, the eject pin insertion hole of the rotary table is an arc-shaped hole having an angular width corresponding to the rotational angle range corresponding to the predetermined vibration width range, so that the rotary table has a predetermined vibration width before the rotation stop. Even if the eject pin is controlled to enter the eject pin insertion hole immediately after entering the rotation angle range corresponding to the range, there is no possibility that the rotary table and the eject pin collide with each other. In addition, the time required for the tip surface of the eject pin to pass through the eject pin insertion hole of the rotary table should be set to be approximately equal to the time from the start of the ejection process until the rotary table becomes stationary. Therefore, the tip surface of the eject pin that has passed through the eject pin insertion hole of the rotary table can be controlled to immediately enter the mold.
However, depending on the case, the time from when the rotary table enters the rotation angle range corresponding to the predetermined vibration range before the rotation stop until it becomes a steady state may be prolonged by some factor, etc. There is a concern that there may be cases where the rotary table is not in a stationary state even when the tip surface is flush with the mold mounting surface of the rotary table. Therefore, in the present invention, after confirming that the rotary table has transitioned to the stationary state, the tip surface of the eject pin enters the mold. Because of this, the manufacturer of the injection molding machine cannot know the mold structure and the mold side ejection mechanism, and the user side of the injection molding machine can choose any mold structure or mold side ejection mechanism. This is because it is considered to design the hole of the mold into which the eject pin (machine side eject pin) enters without clearance.
Further, in the present invention, when the eject pin is in the retreat limit position, the tip of the eject pin is positioned in an annular groove provided on the opposite side of the mold mounting surface of the rotary table. For this reason, the length of the eject pin insertion hole can be made shorter than before, and the time required for the tip surface of the eject pin to pass through the eject pin insertion hole of the rotary table can be shortened. This can also contribute to shortening the molding cycle.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 to 10 relate to an injection molding machine according to an embodiment of the present invention (hereinafter referred to as the present embodiment). The injection molding machine of the present embodiment has two molds on a rotary table at intervals of 180 °. It is a machine that is mounted and configured to intermittently rotate the rotary table 180 degrees alternately in forward and reverse directions, and is a horizontal injection / horizontal open / close type machine. In addition, the injection molding machine of the present embodiment is a machine having a configuration in which a molded product (solidified resin) is attached to the mold side mounted on the rotary table by mold opening.

  FIG. 1 is a main part side view showing a movable die plate, a rotary table and the like in the injection molding machine of the present embodiment, and FIG. 2 is a main part side view of the movable die plate of FIG. 1 viewed from the opposite side of FIG. 3 is a fragmentary plan view showing a part cut along the line AA in FIG. 1. In FIG. 1, some components shown in FIGS. 2 and 3 are omitted. In FIG. 3, some components shown in FIGS. 1 and 2 are omitted.

  1-3, 1 is a base frame of the machine, 2 is a tail stock (not shown) arranged on the base frame 1 and four tie bars fixed at both ends to a fixed die plate, A ball screw mechanism and a toggle link mechanism (not shown) are inserted and guided by the tie bar 2 so as to be able to move back and forth between a tail stock (not shown) and a fixed die plate. The movable die plate 4 that is linearly driven via the rotary table 4 is constituted by a table base 5 and a mold mounting plate 6, and the rotary table 5 is rotatably held by the movable die plate 3. A disk-shaped table base which is driven to rotate via a rotation transmission mechanism by the driving force of a table servo motor (table rotation servo motor), It is fixed on the substrate 5, a rectangular plate-shaped mold attachment plate in which two movable mold (not shown) is mounted at 180 ° intervals.

  In the machine (injection molding machine) of this embodiment, the rotary table 4 is driven to rotate intermittently in the forward and reverse directions alternately by 180 °, and a fixed die plate (not shown) has 180 Two fixed molds (not shown) are attached at intervals of 0 °, and two injection units are provided corresponding to each pair of the movable mold and the fixed mold. Each time the rotary table 4 is rotated by 180 °, the combination of the movable side mold and the fixed side mold is alternately changed, and the injection is performed simultaneously by the two injection units (respectively different resin materials in the two injection units). Thus, the injection molding machine of this embodiment is a machine capable of performing two-color molding. As will be described later, the machine according to the present embodiment is provided with an ejection servo and an ejection mechanism corresponding to each of the pair of the movable side mold and the stationary side mold. When performing, only one of the ejecting servos and the ejecting mechanism is used.

  1 to 3, reference numeral 7 denotes two ejecting servo motors mounted on the movable die plate 3, 8 denotes a drive pulley fixed to the output shaft of each ejecting servo motor 7, and 9 denotes each A ball screw mechanism 10 that converts the rotation of the servo motor 7 for ejection into a linear motion, 10 is a nut body of the ball screw mechanism 9 that is rotatably held on the movable die plate 3, and 11 is screwed into the nut body 10. The screw shaft of the ball screw mechanism 9 that moves linearly by the rotation of the body 10, 12 is a driven pulley fixed to the end of the nut body 10, and 13 is driven by the rotation of the ejection servo motor 7 via the driving pulley 8. A timing belt is transmitted to the pulley 12 and the nut body 10. Reference numeral 14 denotes an eject plate (machine-side eject plate) fixed to the end of the screw shaft 11, and 15 denotes an eject plate 14 that is implanted and fixed to the movable die plate 3 and the rotary table 4. A plurality of eject pins (machine side eject pins) 16 that can be moved forward and backward are formed integrally with the screw shaft 11, and can be moved forward and backward through the movable die plate 3 and the rotary table 4 (machine side eject pins). Pins 18 and 18 are implanted and fixed on the movable die plate 3, and their relative sliding is guided by a sliding bush (not shown) fitted in the hole of the eject plate 14, and cooperate with the eject pin 16. The guide pins guide the linear movement of the eject plate 14 and the eject pin 15.

  1 to 3, 19 is a plurality of annular grooves (provided on the movable die plate 3 side in the table base 5) provided on the opposite side of the mold mounting surface in the rotary table 4, 20 An eject pin insertion hole 20a drilled in the table base 5 of the rotary table 4 and communicating with the annular groove 19, and an eject drilled in the mold mounting plate 6 of the rotary table 4 so as to be exactly overlapped with the eject pin insertion hole 20a. This is an eject pin insertion hole constituted by the pin insertion hole 20b. Here, the eject pin insertion hole 20 (the eject pin insertion hole 20a and the eject pin insertion hole 20b) is an arc-shaped hole having an angular width corresponding to a rotation angle range substantially corresponding to a predetermined damped vibration region before the table rotation is stopped. Is formed. A rotation angle range that roughly corresponds to a predetermined damped vibration region before the table rotation is stopped will be described later with reference to FIGS.

  In the present embodiment, except at the time of the ejecting process, the tip ends of the eject pins 15 and 16 are positioned in the annular groove 19, and when the eject pins 15 and 16 are in the retreat limit position (standby position). The tip surfaces of the eject pins 15 and 16 are configured to slightly recede from the groove bottom surface of the annular groove 19. This ensures that the rotary table 4 can rotate without any trouble even when the tip ends of the eject pins 15 and 16 enter the rotary table 4, and at the same time the eject pins 15 and 16 in the eject ejection process. The amount of advance (in other words, the time for eject ejection) can be reduced.

  FIG. 4 is a diagram showing the transition of the measurement pulse value of the encoder attached to the table servomotor described later, before the rotation table 4 stops rotating. When the turntable 4 is rotated to approximately 180 °, the turntable 4 has a large inertia due to the weight of itself and the mounted mold, so that the turntable 4 is attenuated before completely rotating. Vibrate. The transition of the measurement pulse value 31 of the encoder, which will be described later, attached to the table servo motor when entering the damping vibration region is shown in FIG. 4. In this embodiment, the transition is slightly more than the above damping vibration region. A wide pulse value width is defined as a predetermined vibration width range M, and it is detected whether the rotation table 4 has entered the predetermined vibration width range M before the rotation table 4 stops rotating.

  FIG. 5 is a view showing an angle range M ′ of the rotary table 4 corresponding to the predetermined vibration width range M described above, and the eject pin insertion hole 20 is formed as an arcuate hole having an angle width corresponding to the angle range M ′. Is formed. When the rotary table 4 is stopped from rotating, the eject pins 15 and 16 are located in the center of the arc-shaped eject pin insertion hole 20 or at positions corresponding to the center of the arc-shaped eject pin insertion hole 20. It has become.

  FIG. 6 is a block diagram showing the configuration of the rotation control system of the turntable 4 and the configuration of the control system for the ejecting operation in the machine of this embodiment. In FIG. 6, reference numeral 41 denotes a system controller that performs overall control of the machine (injection molding machine). The system controller 41 includes hardware resources such as arithmetic function elements and memories, and software such as various kinds of application software stored in advance. In cooperation with resources, various processes such as various arithmetic processes, data writing / calling processes, display control processes, and command output processes are executed. In FIG. 6, only the functional blocks directly related to the present invention are drawn in the system controller 41. Details of these functional blocks will be described later. Each functional block includes the above hardware resources, software resources, and the like. Is embodied.

  In FIG. 6, reference numeral 42 denotes a table servomotor (table rotation servomotor) which is a rotation drive source of the rotary table 4, and 43 denotes a drive control of the table servomotor 42 by a command signal from the system controller 41. The servo driver 44, which is attached to the table servo motor 42, detects an amount of rotation of the table servo motor 42 and outputs a measurement pulse value (here, an absolute encoder that outputs an absolute value of the rotation angle) ) 45 is a servo driver that drives and controls the ejection servomotor 7 in response to a command signal from the system controller 41, and 46 detects the amount of rotation of the ejection servomotor 7 and outputs a measurement pulse value (ie, Measurement pulse corresponding to the amount of linear movement of the eject pins 15 and 16 And it outputs the value) encoder (here the absolute encoder) that outputs the absolute value of the rotation angle. In FIG. 6, only one set of the ejecting servomotor 7, the encoder 46, and the servo driver 45 is shown, but actually, one set (not shown) is provided.

  In the system controller 41, 51 is a general control unit that controls each unit in the system controller 41, 52 is a table rotation control condition setting storage unit that stores control conditions for table rotation control during molding operation, and 53 is Under the control of the overall control unit 51, a drive command signal is output to the servo driver 43 based on the control target data stored in the table rotation control condition setting storage unit 52, the measurement pulse value output from the encoder 44, and the like. The table rotation control unit 53a that monitors the measurement pulse value output from the encoder 44 determines whether or not the rotation table 4 is within the predetermined vibration width range M before the rotation stop, and stops the rotation. When entering the predetermined vibration width range M before the operation, the control unit 51 is notified of this fact, and the encoder 44 The measurement pulse value to be output is monitored, it is determined whether or not the rotation table 4 has completely stopped rotating and is in a steady state, and the determination result is notified to the overall control unit 51. The table rotation state determination unit 54 is an ejection operation control setting storage unit that stores control conditions for ejecting operation control during molding operation, and 55 is control target data stored in the ejection operation control setting storage unit 54, This is an ejection operation control unit that outputs a drive command signal to the servo driver 45 based on the measurement pulse value output from the encoder 46 and the like.

  Next, the operation of the eject ejection process in the machine of this embodiment will be described with reference to FIG. FIG. 7 is a flowchart showing the flow of processing of the eject ejection process in the present embodiment.

  Molten resin is injected and filled in the mold cavity, and after a predetermined cooling period, mold opening is performed. Subsequently, when the rotation start timing of the rotary table 4 is reached, the overall control unit 51 to the table rotation control unit 53 A rotation start command is output to the table, and the table rotation control unit 53 drives the table servo motor 42 to rotate in a predetermined direction via the servo driver 43, thereby rotating the rotation table 4 in a predetermined direction. In step S1, the measurement pulse value from the encoder 44 that detects the amount of rotation of the table servo motor 42 is acquired by the table rotation control unit 53. In step S2, the rotation area of the rotation table 4 stops the table rotation. The table rotation state determination unit 53a determines whether or not the predetermined vibration width range M in front is entered, and if the vibration width range M is entered (YES determination in step S2), the process proceeds to step S3. If not (NO in step S2), the process returns to step S1.

  In step S3, the overall control unit 51 gives a command to the ejection operation control unit 55, whereby the ejection operation control unit 55 drives the ejection servo motor 7 to rotate in a predetermined direction via the servo driver 45. The eject pins 15 and 16 are caused to start moving forward so that the tips of the eject pins 15 and 16 enter the arc-shaped eject pin insertion holes 20 from the annular groove 19 of the rotary table 4 damped and oscillated. The tip surface is advanced to a position slightly in front of the eject pin insertion hole 20 protruding into the mold.

  In step S4 subsequent to step S3, whether or not the rotation of the rotary table 4 has completely stopped and transitioned to a static state is determined by the table rotational state determination unit 53a. If YES is determined in S4), the process proceeds to step S6. If not (NO in step S4), the process proceeds to step S5. In step S <b> 5, the overall control unit 51 gives a command to the eject operation control unit 55 to temporarily stop the advance operation of the eject pins 15 and 16. In step S6, the overall control unit 51 gives an instruction to the eject operation control unit 55 to advance the eject pins 15 and 16 to the advance completion position, and the molded product attached to the movable mold (not shown) is moved to the movable mold. Move away from the mold. That is, if NO is determined in step S4 and NO is determined, the eject pins 15 and 16 are advanced to the advance completion position without stopping the advance operation of the eject pins 15 and 16. ing. In the machine of the present embodiment, the time from the start of advancement of the eject pins 15 and 16 to the time when the tip surfaces of the eject pins 15 and 16 advance from the eject pin insertion hole 20 to a position slightly in front of the mold is The rotation table 4 is set to be slightly shorter than the time from the time when the rotation table 4 enters the vibration width range M before the rotation stop to the time when the rotation table 4 becomes in a steady state, and is ejected during normal operation of the machine. The forward movement of the pins 15 and 16 is not temporarily stopped.

  8 to 10 are diagrams for explaining the operation of the eject pins 15 and 16. FIG. 8 is a diagram showing a state in which the rotary table 4 is rotated by, for example, about half of the 180 ° rotation. In the state shown in FIG. In this case, the front end surfaces of the eject pins 15 and 16 are slightly retracted from the groove bottom surface of the annular groove 19. As a result, as described above, even when the tip ends of the eject pins 15 and 16 enter the rotary table 4, it is ensured that the rotary table 4 can rotate without any trouble, and The advance amount of the eject pins 15 and 16 in the eject projecting process (in other words, the time for eject projecting) can be reduced.

  FIG. 9 is a diagram showing a state when the rotary table 4 has been rotated to approximately 180 ° and enters the predetermined vibration width range M before the rotary table 4 completely stops. When the rotary table 4 enters a predetermined vibration width range M before completely stopping, the arc-shaped eject pin insertion hole 20 having an angular width corresponding to the vibration width range M is connected to the tip surfaces of the eject pins 15 and 16. As soon as the rotary table 4 has been rotated to the opposite position and enters the predetermined vibration width range M before the rotary table 4 completely stops, the eject pins 15 and 16 are driven forward, and the tip portions of the eject pins 15 and 16 are moved forward. Enters the eject pin insertion hole 20. Thus, by starting the eject ejection process immediately before the rotary table 4 completely stops (immediately before the rotary table 4 settles), the ejection projection is started after waiting for the rotary table to settle. Compared to the conventional configuration, the molding cycle can be shortened accordingly. In addition, since the eject pin insertion hole 20 of the rotary table 4 is formed as an arc-shaped hole having an angular width corresponding to the predetermined vibration width range M, the rotary table 4 has a predetermined vibration width range before the rotation stop. Even if the eject pins 15 and 16 are controlled to enter the eject pin insertion hole 20 immediately after entering the M, there is no possibility that the rotary table 4 and the eject pins 15 and 16 collide with each other. FIG. 9 shows a state where the eject pins 15 and 16 have entered the end of the arc-shaped eject pin insertion hole 20.

  Here, in this embodiment, the time required for the tip surfaces of the eject pins 15 and 16 to pass through the eject pin insertion hole 20 is the time required for the rotary table 4 to be normally stationary after the ejection is started. The time is set to be approximately the same time or a time that is much shorter than that. Therefore, when the rotary table 4 is operating normally, the distal end surfaces of the eject pins 15 and 16 that have passed through the eject pin insertion hole 20 are not temporarily stopped and are not immediately illustrated. It is possible to control so as to enter the mold.

  However, in some cases, the time until the rotary table 4 enters the rotational angle range corresponding to the predetermined vibration width range M before the rotation stop and becomes stable is prolonged by some factor, etc. There is a concern that there may be cases where the rotary table 4 is not in a static state even when the tip surfaces of the pins 15 and 16 are flush with the mold mounting surface of the rotary table 4. Therefore, in the present embodiment, after confirming that the rotary table 4 has transitioned to the static state, the tip surfaces of the eject pins 15 and 16 are allowed to enter a movable mold (not shown). As described above, the manufacturer of the injection molding machine cannot know about the mold structure or the mold side ejection mechanism, and the user side of the injection molding machine can select any mold. This is because it is considered to adopt a structure and a mold side eject mechanism to design the mold hole into which the eject pins (machine side eject pins) 15 and 16 enter without clearance.

  FIG. 10 shows a state in which the rotary table 4 is completely stopped (stabilized), and in this state, the distal ends of the eject pins 15 and 16 are in a movable mold (not shown). . FIG. 10 shows a state in which the eject pins 15 and 16 are in the advance completion position. In this state, the eject pins 15 and 16 cooperate with a mold-side eject mechanism (not shown). The molded product is pushed away from a movable mold (not shown) by pressing the mold-side eject member.

It is a principal part side view which shows a movable die plate, a rotary table, etc. in the injection molding machine which concerns on one Embodiment of this invention. It is the principal part side view which looked at the movable die plate of FIG. 1 from the opposite side of FIG. It is a principal part cutting top view which cut | disconnects and shows a part along the AA line of FIG. It is explanatory drawing which shows transition of the measurement pulse value of the encoder attached to the servomotor for tables before the rotation table stops rotation in the injection molding machine which concerns on one Embodiment of this invention. FIG. 5 is an explanatory diagram showing an angle range M ′ of the rotary table corresponding to the predetermined vibration width range M shown in FIG. 4. It is a block diagram which shows the structure of the rotation control system of a rotary table, the structure of a control system of eject operation | movement, etc. in the injection molding machine which concerns on one Embodiment of this invention. It is a flowchart which shows the flow of a process of the eject protrusion process in the injection molding machine which concerns on one Embodiment of this invention. In the injection molding machine concerning one embodiment of the present invention, it is an explanatory view showing the state where an eject pin exists in a retreat limit position. In the injection molding machine which concerns on one Embodiment of this invention, it is explanatory drawing which shows the state immediately after the eject pin started protrusion (starting advance). In the injection molding machine which concerns on one Embodiment of this invention, it is explanatory drawing which shows the state which has an eject pin in an advance completion position. It is the principal part sectional view simplified of the conventional injection molding machine using a rotary table.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Base frame 2 Tie bar 3 Movable die plate 4 Rotary table 5 Table base body 6 Mold attachment plate 7 Servo motor for ejection 8 Drive pulley 9 Ball screw mechanism 10 Nut body 11 Screw shaft 12 Driven pulley 13 Timing belt 14 Eject plate 15, 16 Eject Pin 18 Guide pin 19 Annular groove 20 Eject pin insertion hole 20a, 20b Eject pin insertion hole 41 System controller 42 Servo motor for table 43 Servo driver 44 Encoder 45 Servo driver 46 Encoder 51 General control unit 52 Table rotation control condition setting storage unit 53 Table rotation control unit 53a Table rotation state determination unit 54 Ejection operation control setting storage unit 55 Ejection operation control unit

Claims (3)

A rotary table mounted with a mold and driven to rotate intermittently at a predetermined angle, a table servo motor for rotating the rotary table, a first sensor for detecting the rotation amount of the rotary table, and the rotation An eject pin that can be inserted into the mold from the opposite side of the mold mounting surface of the table and can press the mold-side eject member; an eject servomotor that linearly drives the eject pin via a ball screw mechanism; A second sensor for detecting the amount of linear movement of the eject pin, and a controller for controlling the operation of the injection molding machine,
When the controller monitors the output of the first sensor and recognizes that the rotary table has entered a rotation angle range corresponding to a predetermined vibration width range before the rotation stop, the servo motor for ejection Then, the eject pin is moved forward from the retreat limit position so as to enter the eject pin insertion hole formed in the rotary table, and when the rotary table transitions to a static state, the eject servo motor An injection molding machine characterized in that an eject pin is advanced so as to enter the mold. The injection molding machine according to claim 1,
2. The injection molding machine according to claim 1, wherein the eject pin insertion hole formed in the rotary table is an arc-shaped hole having an angular width corresponding to a rotational angle range corresponding to the predetermined vibration width range. In the injection molding machine according to claim 1 or 2,
When the eject pin is in the retreat limit position, the tip of the eject pin is located in an annular groove provided on the opposite side of the mold mounting surface of the rotary table. Machine.

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