JP5063225B2 - Molding machine - Google Patents

Description

  The present invention relates to a molding machine such as an electric drive type die casting machine or an injection molding machine, and in particular, an injection member (an injection plunger in a die casting machine or a pre-plastic type injection molding machine, a screw in an inline screw type injection molding machine). The present invention relates to a technology related to a molding machine that can perform forward acceleration at a very rapid acceleration.

  For example, an electric type inline screw type injection molding machine as a molding machine generally employs a configuration in which only one servomotor (electric servomotor for injection) is used as a drive source for moving the screw back and forth. . By the way, in thin-walled and precision molding, it is essential for good molding to be able to start filling the molten resin quickly in the cavity, but in the configuration using a single injection electric servo motor, injection There is a certain limit to the improvement in acceleration performance (screw acceleration performance), and even if a low-inertia and high-response servomotor is used as an electric servomotor for injection, the acceleration startup time is about 30 ms or more. This is the limit at present.

  Therefore, by using two electric servo motors for injection, the rotation part of one ball screw mechanism is driven to rotate in the same direction by two electric servo motors for injection to improve the acceleration performance of injection. An injection molding machine is also known. However, even with such a configuration, the improvement in the acceleration performance of injection is limited to about 30% as compared with the configuration using one electric servomotor.

  In addition, in the injection system mechanism, a nut servo motor for rotating the nut body and a screw servo motor for rotating the screw shaft are provided for one ball screw mechanism, and the nut servo motor and the screw servo are provided. A configuration in which the injection operation is controlled in cooperation with a motor is also known from Japanese Patent Publication No. 4-64492 (Patent Document 1) and Japanese Patent Laid-Open No. 9-104028 (Patent Document 2). In Patent Document 1, the rotation of the nut servo motor and the rotation of the screw servo motor cause the motor to rotate, but the screw does not move in the axial direction. From this state, the screw servo motor By making the rotation speed of the screw larger than that of the servo motor for nuts, the screw is advanced, and in particular, the control accuracy in the low speed range is improved. Further, in Patent Document 2, a clutch having a short life is created by creating a state suitable for low-speed injection and a state suitable for high-speed injection in cooperation with the rotation of the nut servo motor and the screw servo motor. It is possible to switch between low speed and high speed without using.

  However, in Patent Document 1, as described above, the rotation of the nut servo motor and the rotation of the screw servo motor cooperate to create a state in which the motor rotates but the screw does not move in the axial direction. However, this state continues until the acceleration of the two motors is completed (until the start of the two motors is completed), and the operation behavior of the screw in the acceleration region of the servo motor is not considered. Therefore, the technical idea to improve the acceleration performance of the screw at the initial stage of injection (primary injection) is not found in Patent Document 1.

  Patent Documents 1 and 2 disclose a technique in which high-speed injection is performed by rotationally driving both a nut servo motor and a screw servo motor in a direction in which the screw is advanced. However, even with such a configuration and operation, the acceleration performance of injection is the same as the configuration in which the rotating portion of one ball screw mechanism is rotationally driven in the same direction by the two electric servomotors for injection described above. There is a limit to the improvement.

  In addition, in the techniques shown in Patent Document 1 and Patent Document 2, since the screw advances, the large pressure (load) that the screw receives from the resin is continuously supported by the force of one servo motor. The load applied to the one servo motor is severe.

Accordingly, the applicant of the present application has disclosed a molding machine capable of performing forward acceleration of an injection member (an injection member such as a screw or an injection plunger) with a very rapid acceleration, as described in Japanese Patent Application No. 2007-76868 (hereinafter referred to as Prior Application 1). It was proposed by The molding machine of the prior application 1 includes a first servo motor and a second servo motor as linear motion drive sources of injection members capable of moving back and forth, and the rotating portion is rotationally driven by the rotation of the first servo motor. The linear movement portion of the ball screw mechanism A is fixed to the member holding the base end portion of the injection member, and the rotation portion of the ball screw mechanism A is moved forward and backward by the rotation of the second servo motor. Before starting, the first servo motor is started to rotate in the direction to advance the injection member to accelerate the rotation speed of the first servo motor, and the second servo motor is started to rotate in the direction to retract the injection member. The rotation speed of the second servo motor is accelerated, and the injection member is substantially held at the injection start position until the rotation speeds of the first servo motor and the second servo motor reach the predetermined speeds, respectively. When the rotation speed of the first servo motor and the rotation speed of the second servo motor reach predetermined speeds, the rotation speed of the second servo motor is reduced while continuing the rotation acceleration of the first servo motor. Therefore, the injection member is rapidly advanced. By adopting such an injection control method, the forward acceleration performance of the injection member can be greatly enhanced.
Japanese Examined Patent Publication No. 4-64492 JP-A-9-104028

  By the way, in the prior application 1 described above, the acceleration of the first servo motor is charged by the second servo motor until the timing at which the acceleration of the first servo motor is sufficiently achieved, and the second servo is performed at a predetermined timing. By rapidly decelerating the motor, the sufficiently increased acceleration of the first servo motor is released all at once, and the injection member is rapidly advanced, so the rapid advance performance of the injection member is the second servo motor. It depends on the deceleration performance of the. However, if a configuration using a rotary electric servomotor is employed, there is an influence of rotation inertia of the rotation transmission system, so that the acceleration / deceleration capability has a limit value of about 3 to 4G. Therefore, there has been a limit to further improve the forward acceleration performance of the injection member.

  The present invention has been made in view of the above points, and an object of the present invention is to advance the acceleration of the injection member in a molding machine that performs the acceleration of the injection member on the principle of operation as shown in the prior application 1. The goal is to dramatically improve performance.

In order to achieve the above-described object, the present invention includes a first motor and a second motor as a linear drive source of an injection member that can move forward and backward, and before the injection member starts moving forward, The first motor is driven in the direction to advance the injection member to accelerate the speed of the first motor, and the second motor is started to move in the direction in which the injection member is moved backward to start the movement of the second motor. By accelerating the speed and making the advance amount of the injection member due to the rotation of the first motor equal to the reverse amount of the injection member due to the direct movement of the second motor, the first motor and the first motor the speed of the second motor until each reaches a predetermined speed, so as to hold the start position out morphism the injection member, the speed of the first motor and the second motor when each reaches a predetermined speed, said first The motor In a molding machine that rapidly advances the injection member by decelerating the second motor while continuing acceleration, a rotary motor is used as the first motor, and a linear motor is used as the second motor. Use.

  In the present invention, the acceleration of the first motor, which is the rotation motor, is charged until the timing at which the first motor is sufficiently achieved, and the first motor is sufficiently decelerated at the predetermined timing, thereby rapidly decelerating. The second motor, which works to release the accelerated acceleration at once, is a linear motor. Even if the linear motor is a general linear induction motor, the acceleration / deceleration of about 6 to 8G can be achieved. Therefore, when the second motor is a linear motor, the second motor is more than the second motor. The speed reduction performance of the motor can be greatly improved. Therefore, the speed reduction time of the second motor that rapidly decelerates to release the sufficiently increased acceleration of the first motor at once can be shortened. It becomes possible to dramatically improve the forward acceleration performance. Further, if the linear motor used as the second motor is a tunnel actuator type linear motor, the acceleration / deceleration can be set to 40G or more, and the first motor is suddenly released in order to release the sufficiently increased acceleration. The deceleration time of the second motor that decelerates can be shortened, and the forward acceleration performance of the injection member can be further improved dramatically.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 to 5 relate to a die casting machine according to an embodiment of the present invention (hereinafter referred to as the present embodiment), and FIGS. 1 to 3 illustrate a configuration of a main part of an injection system mechanism of a die cast tomato according to the present embodiment. FIG.

  1 to 3, reference numeral 1 denotes a fixed die plate on which a fixed mold 2 is mounted, 3 denotes a movable mold 4, and the fixed die plate 1 is mounted by a mold opening / closing drive source and a mold opening / closing mechanism (not shown). 5 is a cavity (molded product forming space) formed by both molds 2 and 4 in a mold-clamping state, and 6 is a fixed-side mold 2 at its end. An injection sleeve 7, which is fixed to the inside and communicates with the cavity 5 through the mold inner runner, is a hot water inlet formed on the upper surface of the injection sleeve 6.

  8 is a holding plate that is arranged to face the fixed die plate 1 at a predetermined distance, 9 is a plurality of connection / guide bars that connect the fixed die plate 1 and the holding plate 8, and 10 is a connection / guide bar. The first linear motion block 11, which is inserted and guided by 9 and can be moved back and forth between the fixed die plate 1 and the holding plate 8, is fixed at the base end portion of the first linear motion block 10 and injected. An injection plunger (injection member) 12, which can move back and forth in the sleeve 6, is inserted / guided by a connection / guide bar 9, and can move back and forth between the fixed die plate 1 and the holding plate 8. It is a moving block.

  Reference numeral 13 denotes a rotary motor (a rotary electric servo motor, corresponding to the first motor in the claims) as a linear drive source of the injection plunger 11 mounted on the second linear motion block 12, and reference numeral 14 denotes a rotary motor. 13 is a drive pulley fixed to the output shaft 13, 15 is a ball screw mechanism that converts the rotation of the rotary motor 13 into linear motion, and 16 is a screw shaft of the ball screw mechanism 15 that is rotatably held by the second linear motion block 12. (Rotating portion of the ball screw mechanism 15) and 17 are screwed onto the screw shaft 16, and their end portions are fixed to the first linear motion block 10, and the first linear motion block 10 is rotated by the rotation of the screw shaft 16. A nut body of the ball screw mechanism 15 (linearly moving portion of the first ball screw mechanism 15) 18 that moves back and forth as a unit is fixed to the screw shaft 16, and the rotation of the rotary motor 13 is illustrated as a drive pulley 14. A driven pulley which is transmitted via the timing belt.

  19 is a linear motor (corresponding to the second motor in the claims) as a linear drive source of the injection plunger 11, 20 is a stator of the linear motor 19 fixed to the holding plate 8, and 21 is a stator. This is a mover of the linear motor 19 that can move forward and backward with respect to 20, and has the second linear motion block 12 fixed to the end thereof. Although a linear induction motor is used here as the linear motor 19, a tunnel actuator type linear motor as described later may be used.

  1 to 3, reference numeral 22 denotes a molten metal (molten metal), a metal that has started to solidify, or a solidified metal.

  1 to 3, the rotation of the rotary motor 13 is transmitted to the screw shaft 16 of the ball screw mechanism 15 via the driving pulley 14, the timing belt (not shown), and the driven pulley 18, and the screw shaft 16 rotates. As a result, the nut body 17 moves in the axial direction along the screw shaft 16 so that the first linear motion block 10 and the injection plunger 11 can move forward and backward in the axial direction integrally with the nut body 17. Yes. Further, the linear movement of the mover 21 of the linear motor 19 is transmitted to the second linear motion block 12 and is transferred together with the second linear motion block 12 by the linear motion of the screw shaft 16 of the ball screw mechanism 15 and the ball screw mechanism 15. (The first linear motion block 10 and the injection plunger 11) can move back and forth in the axial direction.

  Thus, in this embodiment, since the injection plunger 11 can be transferred in the axial direction by either the driving force of the rotary motor 13 or the driving force of the linear motor 19, the rotary motor 13 and the linear motor 19 are synchronized. The two motors 13 and 19 are rotated or linearly driven by making the forward movement amount of the injection plunger 11 due to the rotation of the rotary motor 13 equal to the backward movement amount of the injection plunger 11 due to the linear motion of the linear motor 19. However, the injection plunger 11 can create a state in which it does not move in the axial direction.

  FIG. 4 is a diagram showing the acceleration principle of the injection member (here, injection plunger 11) of the present invention. In FIG. 4, the horizontal axis represents time, and the vertical axis represents speed (relative speed). As shown in FIG. 4, prior to actual injection (prior to advancement of the injection plunger 11), the rotation motor 13 starts to rotate in the first rotation direction Ra <b> 1 that advances the injection plunger 11, and the rotation speed of the rotation motor 13. , And the linear motor 19 starts to move linearly (linear movement) in the second linear motion direction La2 that causes the injection plunger 11 to retreat, thereby accelerating the linear motion speed of the linear motor 19 and the injection plunger 11 starts injection. When the rotary motor 13 and the linear motor 19 are accelerated and controlled synchronously under the control of a controller (not shown) so as to remain in the position, the rotational speed of the rotary motor 13 and the linear motion speed of the linear 19 are As it increases, the rotational inertia of the rotating system also increases. Here, the timing tm at which the rotational speed of the rotary motor 13 in the first rotational direction Ra1 is accelerated to a predetermined maximum speed Vm (not necessarily the maximum speed that the motor can output), that is, the first speed of the linear motor 19 If the backward movement of the second linear motion block 12 linearly driven by the linear motor 19 is forcibly prevented at the timing tm when the linear motion speed in the two linear motion directions La2 is accelerated to a predetermined speed −Vm, the static inertia Ignoring the above, the injection plunger 11 advances at a stretch and is accelerated to a speed Vm with a vertical acceleration characteristic. In this way, the injection plunger 11 (injection member) of the present invention is controlled so as to release the acceleration sufficiently increased in the first rotation direction Ra1 of the rotary motor 13 at a stretch and advance the injection plunger 11. The acceleration principle.

  However, forcibly stopping the backward movement of the second linear motion block 12 that has a high speed means that the second linear motion block 12 having a high backward speed is abutted against the holding plate 8. Therefore, it is not practical from the viewpoint of mechanical durability and noise. Therefore, in the present embodiment, forward control of the injection plunger 11 as described below is performed.

  In FIG. 4, for the sake of illustration, the rotational speed of the rotary motor 13 is depicted as a speed corresponding to the linear motion speed of the ball screw mechanism 15 (the same applies to FIG. 5 below).

  One example of forward control of the injection plunger 11 of this embodiment will be described with reference to FIGS. 1 to 3 and FIG. 5. FIG. 5 is an explanatory diagram showing an example of the screw forward control of the present embodiment, in which the horizontal axis represents time, the vertical axis represents speed (relative speed), and the time axis The changes in the rotational speed of the rotary motor 13, the linear motion speed of the linear motor 19, and the forward speed of the injection plunger 11 are shown.

  FIG. 1 shows a state immediately after the molten metal 22 for one shot is supplied into the injection sleeve 6, and at this time, the injection plunger 11 is at the injection start position. When it is confirmed at timing t1 that the hot water supply into the injection sleeve 6 has been completed, the first rotation in which the rotary motor 13 advances the injection plunger 11 under the control of a controller (not shown) that controls the entire die casting machine. The rotation is started in the direction Ra1 and the rotation speed of the rotary motor 13 is accelerated, and the linear motor 19 is started to move linearly (linear movement) in the second linear movement direction La2 in which the injection plunger 11 is moved backward. The injection plunger 11 is driven until the timing t2 when the moving speed is accelerated, the rotating speed of the rotary motor 13 reaches the predetermined speed V1 (accelerated), and the linear movement speed of the linear motor 19 reaches the predetermined speed −V1 (accelerated). Is held at the injection start position. At this time, although the injection plunger 11 is held at the injection start position, the nut body 16 of the ball screw mechanism 15 moves forward with respect to the screw shaft 15, and the mover 21 of the linear motor 19 is moved to the stator 20. Therefore, the second linear motion block 12 is retracted.

  When the rotation speed of the rotary motor 13 in the first rotation direction Ra1 is accelerated to V1 and the linear movement speed of the linear motor 19 in the second linear movement direction La2 is accelerated to -V1, the timing t2 is not shown. The controller rapidly decelerates the linear motion speed in the second linear motion direction La2 of the linear motor 19 toward the speed 0 (zero) while continuing the rotational acceleration of the rotary motor 13 in the first rotational direction Ra1, By releasing the sufficiently increased acceleration in the first rotation direction Ra1 of the rotary motor 13 at a stretch, the injection plunger 11 starts to drive forward with rapid acceleration. That is, the injection plunger 11 is suddenly accelerated from the advance speed 0 (zero) to the advance speed V2 and moves forward from the timing t2 to the timing t3 when the linear motion speed of the linear motor 19 becomes 0 (zero). . Further, at timing t3, the controller (not shown) ends the rotational acceleration of the rotary motor 13, and after timing t3, the control of the rotary motor 13 is switched to constant speed rotation control in the first rotation direction Ra1. As a result, the rotational speed of the rotary motor 13 in the first rotational direction Ra1 becomes the set predetermined maximum speed V2 (not necessarily the maximum speed that the motor can output), and after the timing t3, the injection plunger 11 is predetermined. It is driven forward at a constant speed at the maximum speed V2. As the injection plunger 11 advances, the molten metal 22 in the injection sleeve 11 is rapidly injected and filled into the cavity 5.

  By the control as described above, the injection plunger 11 that has started forward acceleration at the timing t2 is rapidly accelerated from the speed 0 (zero) to the speed V2 between the timing t2 and the timing t3. For example, the injection plunger 11 is accelerated with an acceleration of G on the order of two digits, and the forward acceleration time of the injection plunger 11 from timing t2 to timing t3 is easily achieved to several milliseconds (several milliseconds) or less.

  FIG. 2 shows a state at the timing t <b> 2. At this time, the second linear motion block 12 is slightly separated from the holding plate 8. The linear motion in the second linear motion direction La2 of the linear motor 19 is a linear motion direction in which the second linear motion block 12 is moved backward, and the linear motion speed of the linear motor 19 becomes 0 (zero) after timing t2. At the timing t3, the second linear motion block 12 is in contact with the holding plate 8. That is, after the timing t3, the second linear motion block 12 is supported by the mechanical contact with the holding plate 8. Therefore, after the timing t3, the injection plunger 11 is moved forward to receive the injection plunger 11 from the metal 22. The large pressure (load) is not required to be supported by the linear motor 19. FIG. 3 shows the completed state of injection / filling.

  As described above, in the present embodiment, the acceleration of the rotary motor 13 is charged until the acceleration of the rotary motor 13 (first motor) is sufficiently achieved, and a predetermined timing (here, timing t2). The second motor, which works so as to release the sufficiently increased acceleration of the rotary motor 13 at a stretch by decelerating suddenly when reaching, is the linear motor 19. Although the linear motor 19 in this embodiment is a general linear induction motor, since acceleration / deceleration of about 6 to 8G can be easily achieved, a sufficiently increased acceleration of the rotary motor 13 (first motor) can be achieved at once. The deceleration time of the second motor that suddenly decelerates for release can be shortened, and therefore the forward acceleration performance of the injection plunger 11 (injection member) can be dramatically improved. Moreover, although the rotation motor 13 is inferior in acceleration / deceleration performance compared to the linear motor 19, it can output a high voltage compared to the linear motor 19, and the linear motor 19 is superior in acceleration / deceleration performance compared to the rotation motor 13. The high pressure output has a certain limit (for example, a limit of about 10 kN thrust). The forward movement of the injection plunger 11 that receives a large pressure (load) from the metal 22 by the forward movement is performed by the rotary motor 13. In addition, after the timing t3, the linear motor 19 does not need to support the large pressure (load) that the injection plunger 11 receives from the metal 22 as the injection plunger 11 moves forward. Therefore, it is possible to improve the forward acceleration performance of the injection plunger 11 (injection member) more dramatically. It can be achieved without compromising the sex.

  Next, a modified example of the present embodiment will be described with reference to FIGS. This modified example uses a tunnel actuator type linear motor instead of a linear induction motor as the linear motor 19, and FIG. 6 is an explanatory diagram showing an outline of a configuration example of the tunnel actuator type linear motor. FIG. 7 is an explanatory diagram showing attraction force cancellation in the tunnel actuator type linear motor of FIG.

  In FIG. 6, 20A, 20B, and 20C are stators that are excited and driven at different phases. In each of the stators 20A, 20B, and 20C, 23 is a magnetic pole, 23a is an upper magnetic pole tooth of the magnetic pole 23, and 23b is a magnetic pole 23. Lower magnetic pole teeth, 24 is a magnetic pole, 24a is an upper magnetic pole tooth of the magnetic pole 24, 24b is a lower magnetic pole tooth of the magnetic pole 24, 25 is an iron core, and 26 is a winding wound in the longitudinal direction of the iron core 25. In FIG. 6, reference numeral 21 denotes a mover having a permanent magnet 28 in which N and S poles are alternately arranged along the longitudinal direction.

  In the tunnel actuator type linear motor shown in FIG. 6, the upper magnetic pole teeth 23 a of the magnetic pole 23 and the lower magnetic pole teeth 24 b of the magnetic pole 24 are opposed to each other with a predetermined gap G to form a facing portion. Similarly, the upper magnetic pole teeth 24a of the magnetic pole 24 are opposed to each other with a predetermined gap G to form a facing portion, and the magnetic pole teeth have a staggered structure between adjacent facing portions. And it has the structure where the needle | mover 21 is arrange | positioned between the magnetic pole teeth which comprise each opposing part.

  In the tunnel actuator type linear motor having such a configuration, when the pole pitch P between adjacent magnetic pole tooth centers is set to a predetermined value and the movable element 21 is linearly driven in one direction, the stator 20A is moved to the A phase. The stator 21B is excited and driven in the B phase, and the stator 20C is excited and driven in the C phase, so that the mover 21 is given a thrust in a predetermined direction and linearly moves in one direction. When the mover 21 is linearly driven in the other direction opposite to the above, the stator 20A is excited and driven in the A phase, the stator 20B is excited and driven in the C phase, and the stator 20C is driven and excited in the B phase. Thus, the mover 21 is given a thrust in the opposite direction to the above and moves linearly in the other direction.

  Here, as shown in FIG. 7, in the adjacent facing portions, the directions in which the suction force acts are opposite to each other, so that the suction force can be offset to substantially zero as a whole, With this configuration, sufficient thrust can be obtained, and the movable element 21 can be made lighter than the conventional one as described later, so that acceleration / deceleration of 40 G or more can be easily realized. It has become. Therefore, in the modified example of the present embodiment in which a tunnel actuator type linear motor is used as the linear motor 19, the forward acceleration performance of the injection plunger 11 (injection member) is greater than when a linear induction motor is used as the linear motor 19. Can be further increased.

  The configuration of the tunnel actuator type linear motor is known in Japanese Patent No. 3395155 and the like, and therefore, detailed description thereof will be omitted. Although FIG. 6 shows an example of three-phase excitation, it is possible to adopt a configuration driven by two-phase excitation or a configuration driven by multi-phase excitation higher than four-phase excitation.

  Next, another embodiment of the present invention will be described. FIG. 8 is a view showing a main configuration of an injection system mechanism of an injection molding machine according to another embodiment of the present invention.

  In FIG. 8, reference numeral 31 denotes a head stock, 32 denotes a support plate arranged to face the head stock 31 at a predetermined distance, and 33 is fixed to the head stock 31 and the support plate 32 at both ends. A plurality of connection / guide bars 34, which are connected to the support plate 32, are inserted / guided by the connection / guide bar 33, and can move back and forth between the head stock 31 and the support plate 32. , 35 are also inserted / guided through the connection / guide bar 33 and can move back and forth between the head stock 31 and the support plate 32, and 36 has a base end portion attached to the head stock 31. A fixed heating cylinder 37 is a nozzle provided at the tip of the heating cylinder 36, and 38 is a fixed side where the nozzle 37 is pressed around the resin injection port at least during injection. A mold 39 is a movable mold that can be moved back and forth with respect to the fixed mold 38, 40 is a cavity (molded product forming space) formed by both molds 38 and 39 in a clamped state, 41 is The screw 41 is a screw (injection member) that is disposed in the heating cylinder 36 so as to be able to rotate and move forward and backward, and whose base end portion is rotatably supported by the first linear motion block 34. The first linear motion block 34 is driven to rotate by the driving force of a not-shown measuring electric servo motor and is moved forward and backward integrally with the first linear motion block 34.

  Reference numeral 42 denotes a rotary motor (a rotary electric servo motor, which corresponds to the first motor in the claims) as a linear drive source of the screw 41 mounted on the second linear motion block 35, and 43 denotes the rotary motor 42. The drive pulley fixed to the output shaft of the ball screw 44 is a ball screw mechanism that converts the rotation of the rotary motor 42 into a linear motion, and 45 is a screw shaft of the ball screw mechanism 44 that is rotatably held by the second linear motion block 35 ( The rotating portion of the ball screw mechanism 44, 46 is screwed to the screw shaft 45, and its end is fixed to the first linear motion block 34, and the first linear motion block 34 is integrated with the rotation of the screw shaft 45. The nut body of the ball screw mechanism 34 (linearly moving portion of the ball screw mechanism 34) 47 that moves forward and backward is fixed to the screw shaft 45, and the rotation of the rotary motor 42 is changed to the drive pulley 43, the first not shown. Thailand A driven pulley 48 that is transmitted via the ring belt is a linear motor (corresponding to a second motor in the claims) as a linear motion drive source of the screw 41, and 49 is a linear motor 48 fixed to the support plate 32. The stator 50 is a mover of the linear motor 48 that can move back and forth with respect to the stator 49 and has the second linear motion block 35 fixed to the end thereof. Although a linear induction motor is used here as the linear motor 48, a tunnel actuator linear motor as described with reference to FIGS. 6 and 7 may be used.

  In the injection molding machine according to another embodiment having the configuration shown in FIG. 8, the screw 41 (injection member) can be transferred in the axial direction by the driving force of the rotary motor 42 or the driving force of the linear motor 48. Therefore, the rotary motor 42 and the linear motor 48 are driven in synchronization, and the advance amount of the screw 41 due to the rotation of the rotary motor 42 is made equal to the reverse amount of the screw 41 due to the linear motion of the linear motor 48. Thus, although the two motors 42 and 48 are rotating or linearly moving, it is possible to create a state where the screw 41 is not moved in the axial direction. Therefore, also in the injection molding machine of this other embodiment, by applying the advance control method of the injection plunger 11 as described with reference to FIG. 5 to the advance control of the screw 41, the screw 41 (injection member). It becomes possible to dramatically improve the forward acceleration performance. Further, this can be realized without impairing other operation reliability.

It is explanatory drawing which shows the principal part structure of the injection system mechanism of the die-casting machine which concerns on one Embodiment of this invention. It is explanatory drawing which shows the principal part structure of the injection system mechanism of the die-casting machine which concerns on one Embodiment of this invention. It is explanatory drawing which shows the principal part structure of the injection system mechanism of the die-casting machine which concerns on one Embodiment of this invention. It is explanatory drawing which shows the acceleration principle of the member for injection | emission of this invention. It is explanatory drawing which shows the mode of one example of screw advance control in the die-casting machine which concerns on one Embodiment of this invention. It is explanatory drawing which shows the outline of the structural example of the tunnel actuator type linear motor used with the modification of the die-casting machine which concerns on one Embodiment of this invention. It is explanatory drawing which shows attraction | suction force cancellation in the tunnel actuator type | mold linear motor of FIG. It is explanatory drawing which shows the principal part structure of the injection system mechanism of the injection molding machine which concerns on other embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Fixed die plate 2 Fixed side metal mold 3 Movable die plate 4 Movable side metal mold 5 Cavity 6 Injection sleeve 7 Hot water supply port 8 Holding plate 9 Connection / guide bar 10 1st linear motion block 11 Injection plunger 12 2nd linear motion block 13 Rotation motor (first motor)
14 Drive pulley 15 Ball screw mechanism 16 Screw shaft 17 Nut body 18 Driven pulley 19 Linear motor (second motor)
20, 20A, 20B, 20C Stator 21 Movable element 22 Metal melt (molten metal) or metal that has started to solidify or solidified metal 23 Magnetic pole 23a Upper magnetic pole tooth 23b Lower magnetic pole tooth 24 Magnetic pole 24a Upper magnetic pole tooth 24b Lower magnetic pole tooth 25 Iron core 26 Winding 28 Permanent magnet 31 Headstock 32 Support plate 33 Connection / guide bar 34 First linear motion block 35 Second linear motion block 36 Heating cylinder 37 Nozzle 38 Fixed side die 39 Movable side die 40 Cavity 41 Screw 42 Rotation motor (first motor)
43 Driving pulley 44 Ball screw mechanism 45 Screw shaft 46 Nut body 47 Driven pulley 48 Linear motor (second motor)
49 Stator 50 Movable

Claims (3)

A first motor and a second motor are provided as linear drive sources for the injection member capable of moving forward and backward, and the first motor is moved in a direction to advance the injection member before the injection member starts to advance. Rotation of the first motor is started by accelerating the speed of the first motor by starting driving, and starting the driving of the second motor in the direction of retracting the injection member to accelerate the speed of the second motor. Until the speeds of the first motor and the second motor reach predetermined speeds by equalizing the amount of advancement of the injection member by the same amount as the amount of retraction of the injection member by direct movement of the second motor. the so held in the starting position out shot an injection member, when the speed of the second motor and the first motor respectively reaches a predetermined speed, while continuing the aforementioned acceleration of the first motor, the second 2 motors By performing the fast, in a molding machine so as to rapidly advance the injection member,
A molding machine using a rotary motor as the first motor and a linear motor as the second motor. The molding machine according to claim 1,
The linear motion part of the ball screw mechanism whose rotational part is driven to rotate by the first motor is fixed to the member holding the base end part of the injection member, and the rotational part of the ball screw mechanism is moved forward and backward by the second motor. A molding machine characterized by being advanced. The molding machine according to claim 1 or 2,
The linear motor as the second motor includes a plurality of stators having different driving phases wound with windings and a mover that linearly moves with respect to the stator, and the stator includes magnetic pole teeth. While having a plurality of facing portions facing each other, the plurality of facing portions have a linear structure in which the magnetic pole teeth of the adjacent facing portions take a staggered structure and have permanent magnets between the magnetic pole teeth constituting the facing portion. A molding machine, wherein the mover is arranged.

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