JP5823218B2 - Injection molding machine - Google Patents

Description

  The present invention relates to an injection molding machine.

  The injection molding machine molds a molded product by injecting molten resin from an injection apparatus, filling the cavity of a mold apparatus, and solidifying. The mold apparatus includes a fixed mold and a movable mold. Mold closing, mold clamping, and mold opening of the mold apparatus are performed by a mold clamping apparatus.

  As a mold clamping device, a system using a drive source such as a motor and a toggle mechanism is widely used. However, due to the characteristics of the toggle mechanism, it is difficult to change the mold clamping force, and responsiveness and stability. Is bad. In addition, a bending moment may be generated during the operation of the toggle mechanism, and the mounting surface to which the mold apparatus is attached may be distorted.

  Therefore, a mold clamping device has been proposed that uses a linear motor for the mold opening / closing operation and uses the attractive force of an electromagnet for the mold clamping operation (see, for example, Patent Document 1). In the mold clamping device, current supply to the coil of the electromagnet is performed under the control of the control device.

WO05 / 090052 pamphlet

  The mold apparatus is replaced according to the type of the molded product. When a new mold apparatus is mounted, the mold apparatus is temporarily fixed to the mounting surface with bolts, then the mold is closed, and the bolts are tightened and tightened in a clamped state. Instead of the bolt, a clamp device using hydraulic pressure or magnetic force may be used.

  Since this fastening operation is performed by opening the door installed on the cover of the injection molding machine, the current supply to the mold clamping device is stopped when the door is open in order to eliminate the malfunction caused by the control device. .

  In this state, the method using the toggle mechanism can retain the mold clamping force generated in advance, but the method using the electromagnet cannot retain the mold clamping force. This is because the current supply to the coil of the electromagnet by the control device is interrupted. For this reason, in the method using an electromagnet, the main fastening operation is difficult.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide an injection molding machine capable of mounting a mold apparatus in a state where current supply to the mold clamping apparatus is stopped.

In order to solve the above-described problem , an injection molding machine according to one aspect of the present invention includes:
A first fixing member to which a fixed mold is attached;
A first movable member to which a movable mold is attached;
A second movable member that moves with the first movable member;
A second fixed member disposed between the first movable member and the second movable member;
A first mold clamping force generation mechanism for generating a mold clamping force by an attractive force of an electromagnet between the second fixed member and the second movable member;
A second mold clamping force generation mechanism for generating a predetermined mold clamping force in a state where current supply to the first mold clamping force generation mechanism is stopped ,
The second mold clamping force generation mechanism is:
A movement suppressing unit that suppresses movement of the second movable member in the mold opening direction;
And a mold thickness adjusting unit that adjusts an interval between the first movable member and the second movable member .

  ADVANTAGE OF THE INVENTION According to this invention, the injection molding machine which enables attachment of a mold apparatus in the state which stopped the electric current supply to the mold clamping apparatus is provided.

The figure which shows the state at the time of mold closing of the injection molding machine by 1st Embodiment of this invention. The figure which shows the state at the time of mold opening of the injection molding machine by 1st Embodiment of this invention. The figure which shows the state at the time of metal mold | die attachment of the injection molding machine by 1st Embodiment of this invention. The figure which shows the state at the time of metal mold | die attachment of the injection molding machine by 2nd Embodiment of this invention. The figure which shows the state at the time of metal mold | die attachment of the injection molding machine by 3rd Embodiment of this invention. The figure which shows the state at the time of metal mold | die attachment of the injection molding machine by 4th Embodiment of this invention.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. In each of the drawings, the same or corresponding components are denoted by the same or corresponding reference numerals, and description thereof will be omitted. Further, a description will be given assuming that the moving direction of the movable platen when performing mold closing is the front and the moving direction of the movable platen when performing mold opening is the rear.

[First Embodiment]
FIG. 1 is a view showing a state when the injection molding machine according to the first embodiment of the present invention is closed. FIG. 2 is a view showing a state when the injection molding machine according to the first embodiment of the present invention is opened.

  In the figure, 10 is a mold clamping device, Fr is a frame of an injection molding machine, Gd is a guide composed of two rails laid on the frame Fr, and 11 is a fixed platen (first fixing member). The fixed platen 11 may be provided on a position adjustment base Ba that is movable along a guide Gd that extends in the mold opening / closing direction (left-right direction in the drawing). The fixed platen 11 may be placed on the frame Fr.

  A movable platen (first movable member) 12 is disposed facing the fixed platen 11. The movable platen 12 is fixed on the movable base Bb, and the movable base Bb can run on the guide Gd. Thereby, the movable platen 12 is movable in the mold opening / closing direction with respect to the fixed platen 11.

  A rear platen (second fixing member) 13 is disposed at a predetermined distance from the fixed platen 11 and parallel to the fixed platen 11. The rear platen 13 is fixed to the frame Fr via the leg portion 13a.

  Between the fixed platen 11 and the rear platen 13, four tie bars 14 (only two of the four tie bars 14 are shown in the figure) are installed as connecting members. The fixed platen 11 is fixed to the rear platen 13 via the tie bar 14. A movable platen 12 is disposed along the tie bar 14 so as to freely advance and retract. A guide hole (not shown) for penetrating the tie bar 14 is formed at a position corresponding to the tie bar 14 in the movable platen 12. In addition, you may make it form a notch instead of a guide hole.

  A screw portion (not shown) is formed at the front end portion (right end portion in the drawing) of the tie bar 14, and the front end portion of the tie bar 14 is fixed to the fixed platen 11 by screwing and tightening a nut n1 to the screw portion. The rear end of the tie bar 14 is fixed to the rear platen 13.

  A fixed mold 15 is attached to the fixed platen 11, and a movable mold 16 is attached to the movable platen 12. The fixed mold 15 and the movable mold 16 are brought into contact with and separated from each other as the movable platen 12 advances and retreats. Closing, mold clamping and mold opening are performed. As the mold clamping is performed, a cavity space (not shown) is formed between the fixed mold 15 and the movable mold 16, and a molten resin (not shown) injected from the injection nozzle 18 of the injection device 17 is formed in the cavity. The space is filled. A mold apparatus 19 is configured by the fixed mold 15 and the movable mold 16.

  The suction plate 22 (second movable member) is disposed in parallel with the movable platen 12. The suction plate 22 is fixed to the slide base Sb via the mounting plate 27, and the slide base Sb can travel on the guide Gd. As a result, the suction plate 22 can move back and forth behind the rear platen 13. The suction plate 22 may be formed of a magnetic material. The attachment plate 27 may not be provided. In this case, the suction plate 22 is directly fixed to the slide base Sb.

  The rod 39 is connected to the suction plate 22 at the rear end portion and is connected to the movable platen 12 at the front end portion. Therefore, the rod 39 is moved forward as the suction plate 22 moves forward when the mold is closed to move the movable platen 12 forward, and is retracted and moved backward as the suction plate 22 moves back when the mold is opened. Retreat. For this purpose, a hole 41 is formed in the central portion of the rear platen 13 for allowing the rod 39 to pass therethrough.

  The linear motor 28 is a mold opening / closing drive unit for moving the movable platen 12 forward and backward, and is disposed, for example, between the suction plate 22 connected to the movable platen 12 and the frame Fr. The linear motor 28 may be disposed between the movable platen 12 and the frame Fr.

  The linear motor 28 includes a stator 29 and a mover 31. The stator 29 is formed on the frame Fr in parallel with the guide Gd and corresponding to the movement range of the slide base Sb. The mover 31 is formed at a lower end of the slide base Sb so as to face the stator 29 and over a predetermined range.

  The mover 31 includes a core 34 and a coil 35. The core 34 includes a plurality of magnetic pole teeth 33 that are protruded toward the stator 29 and formed at a predetermined pitch, and the coil 35 is wound around each magnetic pole tooth 33. The magnetic pole teeth 33 are formed in parallel to each other in a direction perpendicular to the moving direction of the movable platen 12. The stator 29 includes a core (not shown) and a permanent magnet (not shown) formed to extend on the core. The permanent magnet is formed by alternately magnetizing the N and S poles. A position sensor 75 that detects the position of the mover 31 is disposed.

  When the linear motor 28 is driven by supplying a predetermined current to the coil 35, the mover 31 is moved back and forth. Along with this, the suction plate 22 and the movable platen 12 are advanced and retracted, and the mold can be closed and opened. The linear motor 28 is feedback-controlled based on the detection result of the position sensor 75 so that the position of the mover 31 becomes a set value.

  In the present embodiment, the permanent magnet is disposed on the stator 29 and the coil 35 is disposed on the mover 31, but the coil is disposed on the stator and the permanent magnet is disposed on the mover. You can also. In this case, since the coil does not move as the linear motor 28 is driven, wiring for supplying power to the coil can be easily performed.

  As the mold opening / closing drive unit, a rotary motor and a ball screw mechanism that converts the rotary motion of the rotary motor into a linear motion may be used instead of the linear motor 28.

  The electromagnet unit 37 generates a mold clamping force between the rear platen 13 and the suction plate 22 by the suction force of the electromagnet. This adsorption force is transmitted to the movable platen 12 via the rod 39.

  The mold clamping device 10 is configured by the fixed platen 11, the movable platen 12, the rear platen 13, the suction plate 22, the linear motor 28, the electromagnet unit 37, the rod 39, and the like. Further, the electromagnet unit 37 and the like constitute a first mold clamping force generation mechanism.

  The electromagnet unit 37 includes an electromagnet 49 formed on the rear platen 13 side and a suction portion 51 formed on the suction plate 22 side. The suction portion 51 is formed in a predetermined portion of the front end surface of the suction plate 22, for example, a portion that surrounds the rod 39 in the suction plate 22 and faces the electromagnet 49. Further, a groove 45 is formed around a predetermined portion of the rear end surface of the rear platen 13, for example, the rod 39, a core 46 is formed inside the groove 45, and a yoke 47 is formed outside the groove 45. A coil 48 is wound around the core 46 in the groove 45.

  In this embodiment, the electromagnet 49 is formed separately from the rear platen 13 and the attracting portion 51 is formed separately from the attracting plate 22, but the electromagnet is part of the rear platen 13 and the attracting portion is part of the attracting plate 22. May be formed. Moreover, the arrangement of the electromagnet and the attracting part may be reversed. For example, the electromagnet 49 may be provided on the suction plate 22 side, and the suction portion 51 may be provided on the rear platen 13 side.

  When an electric current is supplied to the coil 48 in the electromagnet unit 37, the electromagnet 49 is driven to attract the attracting part 51 and generate a mold clamping force.

  Driving of the linear motor 28 and the electromagnet 49 of the mold clamping device 10 is controlled by the control device 60. The control device 60 includes a CPU, a memory, and the like, and supplies current to the coil 35 of the linear motor 28 and the coil 48 of the electromagnet 49 according to the result calculated by the CPU. A load detector 55 is connected to the control device 60. The load detector 55 is installed at a predetermined position (a predetermined position between the fixed platen 11 and the rear platen 13) of at least one tie bar 14 in the mold clamping device 10, and detects a load applied to the tie bar 14. . The load detector 55 is configured by a sensor that detects the amount of extension of the tie bar 14, for example. The load detected by the load detector 55 is sent to the control device 60.

  Next, the operation of the mold clamping device 10 will be described.

  The mold closing process is controlled by the mold opening / closing processor 61 of the control device 60. In the state of FIG. 2 (the state of mold opening), the mold opening / closing processor 61 supplies current to the coil 35 to drive the linear motor 28. The movable platen 12 moves forward, and the movable mold 16 is brought into contact with the fixed mold 15 as shown in FIG. At this time, a gap δ is formed between the rear platen 13 and the suction plate 22, that is, between the electromagnet 49 and the suction portion 51. Note that the force required for mold closing is sufficiently reduced compared to the mold clamping force.

  Subsequently, the mold clamping processing unit 62 of the control device 60 controls the mold clamping process. The mold clamping processing unit 62 supplies current to the coil 48 of the electromagnet 49 and attracts the attracting unit 51 to the electromagnet 49. Along with this, the clamping force is transmitted to the movable platen 12 via the suction plate 22 and the rod 39, and clamping is performed.

  The mold clamping force is detected by the load detector 55. The detected mold clamping force is sent to the control device 60, and the mold clamping processing unit 62 adjusts the current supplied to the coil 48 so that the mold clamping force becomes a set value, and performs feedback control. During this time, the molten resin melted in the injection device 17 is injected from the injection nozzle 18 and filled into the cavity space of the mold device 19.

  When the resin in the cavity space is cooled and solidified, the mold opening / closing processor 61 controls the mold opening process. The mold clamping processing unit 62 stops supplying current to the coil 48 of the electromagnet 49 in the state of FIG. Accordingly, the linear motor 28 is driven, the movable platen 12 is moved backward, and the movable mold 16 is moved backward as shown in FIG. 2 to open the mold.

Next, mold thickness adjustment at the time of replacement of the mold apparatus 19 will be described.
When a new mold apparatus 19 is attached along with the replacement of the mold apparatus 19, the thickness of the mold apparatus 19 changes, and a gap formed between the rear platen 13 and the suction plate 22 when the mold closing is completed. δ changes.

  Therefore, the injection molding machine includes a mold thickness adjusting device 70 that adjusts the gap δ according to the thickness of the mold device 19. The mold thickness adjusting device 70 includes a mold thickness adjusting motor 71, a gear 72, a nut 73, a rod 39, and the like. The rod 39 passes through the central portion of the suction plate 22, and a screw 43 is formed at the rear end portion of the rod 39. The screw 43 and a nut 73 that is rotatably supported by the suction plate 22 are screwed together. A large-diameter gear (not shown) is formed on the outer peripheral surface of the nut 73, and this gear and a small-diameter gear 72 attached to the output shaft 71a of the mold thickness adjusting motor 71 are engaged with each other. The nut 73 and the screw 43 constitute a movement direction conversion unit, and the rotation direction of the nut 73 is converted into a straight movement of the rod 39 in the movement direction conversion unit.

  When the mold thickness adjusting motor 71 is driven in accordance with the thickness of the mold apparatus 19 and the nut 73 is rotated by a predetermined amount with respect to the screw 43, the position of the rod 39 with respect to the suction plate 22 is adjusted, and the fixed platen 11 and the position of the suction plate 22 with respect to the movable platen 12 are adjusted, and the gap δ can be set to an optimum value. That is, the mold thickness is adjusted by changing the distance between the movable platen 12 and the suction plate 22 in the mold opening / closing direction (left and right direction in the figure).

  The mold thickness adjusting motor 71 may be a servo motor and may include an encoder unit 71b. The encoder unit 71 b detects the amount of rotation of the output shaft 71 a of the mold thickness adjusting motor 71 and transmits the detection result to the control device 60. The control device 60 performs feedback control of the mold thickness adjusting motor 71 so that the gap δ becomes a set value.

  The mold thickness adjusting motor 71 may be a motor with a brake. The brake portion 71c of the mold thickness adjusting motor 71 may have a general configuration, for example, an electromagnetic brake including an electromagnet. The electromagnetic brake allows the rotation of the output shaft 71a of the mold thickness adjusting motor 71 when the electromagnet is energized, and restricts the rotation of the output shaft 71a when the electromagnet is not energized. In addition, the brake part 71c may have an air cylinder etc. as a drive source instead of an electromagnet, and is not limited to an electromagnetic brake.

  Next, attachment of the mold apparatus 19 will be described with reference to FIG. FIG. 3 shows a state when the mold of the injection molding machine according to the first embodiment of the present invention is attached, and shows a state where a predetermined mold clamping force is generated between the fixed platen 11 and the movable platen 12.

  When a new mold apparatus 19 is attached, the mold apparatus 19 is temporarily fixed to the fixed platen 11 with bolts while being suspended by a crane or the like. Thereafter, the movable platen 12 moves forward and contacts the mold device 19, and then the mold device 19 is clamped. In the clamped state, the fixed mold 15 is fixed to the fixed platen 11 and the movable mold 16 is fixed to the movable platen 12 with bolts. Instead of the bolt, a clamp device using hydraulic pressure or magnetic force may be used.

  Since the main fastening operation is performed by opening a door installed on the cover of the injection molding machine, the current supply to the mold clamping device 10 (specifically, the first mold clamping force generating mechanism) is stopped (hereinafter referred to as “the mold clamping force generation mechanism”). , Also referred to as “stop state”). This is to eliminate malfunctions caused by the control device 60.

  In the stop state, drive control of a drive source (including the electromagnet 49, the linear motor 28, and the mold thickness adjusting motor 71) whose operation is feedback-controlled based on detection results of various detectors is automatically stopped. The servo may be off.

  In the stop state, the power supply to the coil 48 of the electromagnet 49 by the control device 60 is interrupted, so that the attracting force of the electromagnet 49 cannot be used as a mold clamping force.

  Therefore, the second mold clamping force generation mechanism 100 that generates a predetermined mold clamping force in a state where the current supply to the first mold clamping force generation mechanism is stopped is used.

  The second mold clamping force generation mechanism 100 includes a movement suppressing unit 110 that suppresses the backward movement (movement in the mold opening direction) of the suction plate 22 and a mold thickness adjusting device 70. The second mold clamping force generation mechanism 100 generates a predetermined mold clamping force with the door closed and with the current supply to the coil 48 of the electromagnet 49 stopped.

  The movement suppression unit 110 suppresses the backward movement of the suction plate 22 by, for example, locking the suction plate 22 with respect to the rear platen 13. The movement suppression unit 110 includes a locking hole 111 provided on the suction plate 22 side (movable side), a locking pin 112 provided on the rear platen 13 side (fixed side), and the like.

  The locking hole 111 is formed in the slide base Sb integrated with the suction plate 22, for example. A plurality of the locking holes 111 (only one is shown in FIG. 3) may be formed at intervals in the forward / backward direction of the slide base Sb.

  The locking pin 112 restricts advancement and retraction of the slide base Sb when inserted into the locking hole 111 as shown in FIG. 3, and slide base Sb when it comes out of the locking hole 111 as shown in FIGS. Allow advancement and retreat.

  The locking hole 111 may be formed in a member arranged on the suction plate 22 side with respect to the rod 39 among the movable members such as the suction plate 22 and the mounting plate 27 instead of the slide base Sb. . Similarly, the locking pin 112 may be supported by a member on the fixed side such as the frame Fr so as not to advance or retreat, instead of the rear platen 13.

  The arrangement of the locking holes 111 and the locking pins 112 may be reversed, and the locking holes 111 may be provided in the fixed member and the locking pins 112 may be provided in the movable member.

  The movement suppressing unit 110 may further include a guide unit 113 that guides the locking pin 112 in the insertion / extraction direction, a driving device 114 that drives the locking pin 112, and the like. The guide part 113 and the drive device 114 are fixed to the rear platen 13, for example. The driving device 114 separates the locking pin 112 from the slide base Sb at least while the slide base Sb moves forward and backward. The drive device 114 may be electric or hydraulic.

  In addition, as a method for restricting the advance / retreat of the suction plate 22, there are screw fastening, vacuum suction, magnetic suction and the like in addition to pin fastening. In the case of magnetic attraction, for example, a magnet clamp or a magnet stand is used, and both may be used in combination. The magnet clamp and the magnet stand may be provided on the fixed side or may be provided on the movable side.

  Next, the operation of the second mold clamping force generating mechanism 100 configured as described above will be described. This operation is performed after the temporary fixing operation of the mold apparatus 19 and is controlled by the mold clamping force application unit 101 provided in the control apparatus 60.

  First, the mold clamping force application unit 101 drives the linear motor 28 in order to align the locking pin 112 and the locking hole 111. The mold clamping force application unit 101 inserts the locking pin 112 into the locking hole 111 after the alignment. After the insertion, the slide base Sb and consequently the suction plate 22 cannot move in the front-rear direction.

  Next, the mold clamping force application unit 101 drives the mold thickness adjusting device 70 to try to separate the movable platen 12 and the suction plate 22 in the front-rear direction. Since the backward movement of the suction plate 22 is limited, the movable platen 12 moves forward, the movable mold 16 is pressed against the fixed mold 15, and a mold clamping force is generated.

  As described above, the mold clamping force application unit 101 drives the mold thickness adjusting device 70 in a state where the backward movement of the suction plate 22 is suppressed by the movement suppressing unit 110, so that the fixed platen 11 and the movable platen 12 are interposed. Apply clamping force. The mold clamping force is maintained by the movement suppressing unit 110 even after the mold thickness adjusting device 70 is stopped. Therefore, since the mold clamping force can be maintained in the stopped state, the main clamping operation of the mold apparatus 19 can be performed.

  When the mold clamping force is maintained in the stopped state, the rotation of the nut 73 in the direction to release the mold clamping force may be limited by the braking force of the brake portion 71c to maintain the mold clamping force. Note that the rotation of the nut 73 can be limited to some extent by the frictional force between the nut 73 and the screw 43.

  In the present embodiment, after the locking pin 112 is inserted into the locking hole 111, the mold clamping force is generated by the mold thickness adjusting device 70, but the present invention is not limited to this. For example, the locking pin 112 may be inserted into the locking hole 111 in a state where the clamping force is generated by the electromagnet 49. The movement suppressing unit 110 can maintain a predetermined mold clamping force even after the electromagnet 49 is stopped. In this case, the movement suppressing unit 110 constitutes a mold clamping force maintaining mechanism, and the mold clamping force maintaining mechanism may not include the mold thickness adjusting device 70. In this case, the locking hole 111 or the locking pin 112 only needs to be arranged on the movable member, and the movable member is a member arranged on the suction plate 22 side with the rod 39 as a reference. Even if it is, it may be a member arranged on the movable platen 12 side or the rod 39.

[Second Embodiment]
FIG. 4 shows a state when the mold is attached to the injection molding machine according to the second embodiment of the present invention, and shows a state where a predetermined mold clamping force is generated between the fixed platen 11 and the movable platen 12.

  In addition to the mold thickness adjusting device 70, the second mold clamping force generating mechanism 200 according to the present embodiment moves the suction plate 22 forward as a movement suppressing unit that suppresses the backward movement (movement in the mold opening direction) of the suction plate 22. An urging portion for urging in the mold closing direction is provided. As the urging unit, for example, a spring 210 or the like is used as shown in FIG. The second mold clamping force generating mechanism 200 generates a predetermined mold clamping force with the door closed and with the current supply to the coil 48 of the electromagnet 49 stopped.

  The spring 210 is used when the new mold apparatus 19 is permanently fixed. At the time of the final fastening operation, the one end portion 211 of the spring 210 is fixed to the spring attachment portion 220 fixed to the frame Fr. The other end 212 of the spring 210 is fixed to the slide base Sb integrated with the suction plate 22.

  In addition, although the one end part 211 of the spring 210 of this embodiment is fixed to the spring attaching part 220, it may be fixed to the flame | frame Fr and should just be fixed to the member of the fixed side. Similarly, the other end portion 212 of the spring 210 is fixed to the slide base Sb, but may be fixed to the suction plate 22 and is arranged on the suction plate 22 side with respect to the rod 39 among the movable members. What is necessary is just to be fixed to the member.

  Examples of a method for fixing the end portions 211 and 212 of the spring 210 include pinning, screwing, vacuum adsorption, and magnetic adsorption. In the case of magnetic attraction, for example, a magnet clamp or a magnet stand is used, and both may be used in combination. The magnet clamp and the magnet stand may be provided on the spring mounting part 220 side or the slide base Sb side.

  As shown in FIG. 4, the spring mounting portion 220 may be disposed in front of the slide base Sb, or may be disposed in the rear of the slide base Sb. Also in the case of being arranged rearward, the biasing direction of the spring is set to the front (mold closing direction).

  Next, the operation of the second mold clamping force generating mechanism 200 configured as described above will be described. This operation is performed after the temporary fixing operation of the mold apparatus 19 and is controlled by the mold clamping force application unit 201 provided in the control apparatus 60.

  First, the mold clamping force application unit 201 drives the linear motor 28 to advance the movable platen 12 and bring the movable mold 16 into contact with the fixed mold 15. At this time, a gap δ is formed between the electromagnet 49 and the attracting part 51. Note that the gap δ may not be present.

  Thereafter, one end 211 of the spring 210 is fixed to the spring mounting portion 220, and the other end 212 of the spring 210 is fixed to the slide base Sb. The spring 210 urges the slide base Sb and eventually the suction plate 22 forward (rightward in the drawing) to suppress the backward movement of the suction plate 22.

  Next, the mold clamping force application unit 201 drives the mold thickness adjusting device 70 to try to separate the movable platen 12 and the suction plate 22 in the front-rear direction. Since the backward movement of the suction plate 22 is suppressed by the spring 210, the movable platen 12 moves forward, the movable mold 16 is pressed against the fixed mold 15, and a mold clamping force is generated. The clamping force includes the biasing force of the spring 210.

  In this manner, the mold clamping force application unit 201 drives the mold thickness adjusting device 70 in a state where the suction plate 22 is prevented from retreating by the spring 210, thereby clamping the mold between the fixed platen 11 and the movable platen 12. Apply force. This mold clamping force is maintained by the spring 210 even after the mold thickness adjusting device 70 is stopped. Therefore, since the mold clamping force can be maintained in the stopped state, the main clamping operation of the mold apparatus 19 can be performed.

  When the mold clamping force is maintained in the stopped state, the rotation of the nut 73 in the direction to release the mold clamping force may be limited by the braking force of the brake portion 71c to maintain the mold clamping force. Note that the rotation of the nut 73 can be limited to some extent by the frictional force between the nut 73 and the screw 43.

  In the present embodiment, after suppressing the retraction of the suction plate 22 by the spring 210, the mold clamping force is generated by the mold thickness adjusting device 70. However, the present invention is not limited to this. For example, the retraction of the suction plate 22 may be suppressed by the spring 210 in a state where the clamping force is generated by the electromagnet 49. The spring 210 can maintain a predetermined clamping force even after the electromagnet 49 is stopped. In this case, the mold clamping force maintaining mechanism is configured by the movement restraining portion including the spring 210, and the mold clamping force maintaining mechanism may not include the mold thickness adjusting device 70. In this case, the other end 212 of the spring 210 may be fixed to the movable member, and the movable member is a member arranged on the suction plate 22 side with the rod 39 as a reference. Alternatively, it may be a member arranged on the movable platen 12 side or the rod 39.

[Third Embodiment]
FIG. 5 shows a state when the mold of the injection molding machine according to the third embodiment of the present invention is attached, and shows a state where a predetermined mold clamping force is generated between the fixed platen 11 and the movable platen 12.

  The second mold clamping force generation mechanism 300 according to the present embodiment includes a movement suppressing unit that suppresses the backward movement (movement in the mold opening direction) of the suction plate 22 in addition to the mold thickness adjusting device 70. The movement suppressing unit uses the residual magnetic flux after the current supply of the electromagnet is completed. The second mold clamping force generation mechanism 300 generates a predetermined mold clamping force with the door closed and with the current supply to the coil 48 of the electromagnet 49 stopped.

  Next, the operation of the second mold clamping force generating mechanism 300 configured as described above will be described. This operation is performed after the temporary fixing operation of the mold apparatus 19 and is controlled by a mold clamping force application unit 301 provided in the control apparatus 60. The mold clamping force application unit 301 includes a movement suppressing unit.

  First, the mold clamping force application unit 301 drives the linear motor 28 and the mold thickness adjusting device 70 so that there is no gap δ (see FIG. 1) between the electromagnet 49 and the attracting unit 51. Further, the mold clamping force application unit 301 supplies current to the coil 48 of the electromagnet 49 to cause the electromagnet 49 to attract and attract the attracting portion 51 and to cause the rear platen 13 to attract and attract the attracting plate 22.

  Next, the mold clamping force application unit 301 ends the current supply to the coil 48. At this time, since there is no gap δ (see FIG. 1), a sufficient attracting force is generated by the residual magnetic flux after the end of current supply. Accordingly, the suction plate 22 is prevented from moving backward (moving in the mold opening direction). As described above, the mold clamping force application unit 301 includes the movement suppressing unit.

  Next, the mold clamping force application unit 301 drives the mold thickness adjusting device 70 to try to separate the movable platen 12 and the suction plate 22 in the front-rear direction. Since the suction plate 22 is attracted to the rear platen 13 and does not move backward, the movable platen 12 moves forward, the movable mold 16 is pressed against the fixed mold 15, and a mold clamping force is generated.

  In this manner, the mold clamping force application unit 301 drives the mold thickness adjusting device 70 in a state where the retraction of the suction plate 22 is suppressed by the residual magnetic flux after the current is supplied, so that the fixed platen 11 and the movable platen 12 are moved. A clamping force is applied between them. This mold clamping force is maintained even after the mold thickness adjusting device 70 is stopped. Therefore, since the mold clamping force can be maintained in the stopped state, the main clamping operation of the mold apparatus 19 can be performed.

  When the mold clamping force is maintained in the stopped state, the rotation of the nut 73 in the direction to release the mold clamping force may be limited by the braking force of the brake portion 71c to maintain the mold clamping force. Note that the rotation of the nut 73 can be limited to some extent by the frictional force between the nut 73 and the screw 43.

  In this embodiment, after the suction plate 22 is brought into contact with and attracted to the rear platen 13 by the residual magnetic flux of the electromagnet 49, the mold clamping force is generated by the mold thickness adjusting device 70. However, the present invention is not limited to this. For example, a mold clamping force may be generated and the gap δ may be eliminated by supplying a current to the electromagnet 49 with a slight gap δ formed (the gap δ can be adjusted by the mold thickness adjusting device 70). . Even after the electromagnet 49 is stopped, a predetermined clamping force can be maintained by the residual magnetic flux. In this case, the movement suppressing unit included in the mold clamping force applying unit 301 constitutes a mold clamping force maintaining mechanism, and the mold clamping force maintaining mechanism may not include the mold thickness adjusting device 70.

[Fourth Embodiment]
FIG. 6 shows a state when the mold of the injection molding machine according to the fourth embodiment of the present invention is attached, and shows a state where a predetermined mold clamping force is generated between the fixed platen 11 and the movable platen 12. In this state, a gap δ is formed between the rear platen 13 and the suction plate 22.

  The second mold-clamping force generation mechanism 400 includes a portion that is fixed to the movable platen 12 and a portion that is fixed to the fixed platen 11 while the movable die 16 is in contact with the fixed die 15. An attracting device is provided that attracts the user. As the attracting device, for example, a spring 410 or the like is used as shown in FIG. A plurality of springs 410 may be installed. The second mold clamping force generation mechanism 400 generates a predetermined mold clamping force in a state where the current supply to the coil 48 of the electromagnet 49 is stopped. Since the second mold clamping force generation mechanism 400 does not include the mold thickness adjusting device 70, it is possible to generate a predetermined mold clamping force regardless of the open / closed state of the door.

  The spring 410 is used when the new mold apparatus 19 is permanently fixed. During the final fastening operation, one end 411 of the spring 410 is fixed to the fixed platen 11, and the other end 412 of the spring 410 is fixed to the movable platen 12.

  Examples of the fixing method include pinning, screwing, vacuum adsorption, and magnetic adsorption. In the case of magnetic attraction, for example, a magnet clamp or a magnet stand is used, and both may be used in combination. The magnet clamp and the magnet stand may be provided on the movable platen 12 side or the fixed platen 11 side.

  Since the clamping force is generated between the movable platen 12 and the fixed platen 11 by the attractive force of the spring 410, the clamping force is generated in the state where the drive control of the clamping device 10 is stopped. Nineteen main fastening operations can be performed.

  Note that the one end 411 of the spring 410 according to the present embodiment is fixed to the fixed platen 11, but may be fixed to the frame Fr, the tie bar 14, or the like as long as it is fixed to a member on the fixed side. Similarly, the other end portion 412 of the spring 410 is fixed to the movable platen 12, but may be fixed to the slide base Sb, the suction plate 22, or the like, as long as it is fixed to the movable member. For example, the spring 410 may have one end 411 fixed to the spring mounting portion 220 and the other end 412 fixed to the slide base Sb, similarly to the spring 210 shown in FIG.

  In the present embodiment, the mold clamping force is generated by the spring 410 in the stopped state, but the present invention is not limited to this. For example, the spring 410 may be attached after the clamping force is generated by the electromagnet 49. The spring 410 can maintain a predetermined clamping force even after the electromagnet 49 is stopped. In this case, the spring 410 forms a clamping force maintaining mechanism.

  The attracting device according to the present embodiment is a spring-type attracting device that uses the biasing force of the spring 410. However, a fluid-type attracting device that uses fluid pressure such as hydraulic pressure or air pressure, a screw-type attracting device, or the like may be used. Good. The screw-type attracting device is configured by a shaft fixed to the fixed platen 11 and penetrating the movable platen 12, a nut screwed into a screw formed at a rear end portion of the shaft, and a motor for rotating the nut. The When the motor is driven and the nut rotates in a predetermined direction, a mold clamping force is generated as the movable platen 12 moves forward. The shaft may be fixed to the movable platen 12 and may pass through the fixed platen 11. In this case, a screw is formed at the front end of the shaft. Further, the shaft may pass through the movable platen 12 and the fixed platen 11. In this case, screws are formed at the front end portion and the rear end portion of the shaft, and nuts are screwed into the respective screws, and the two nuts are relative to each other. Rotated in the opposite direction.

  The first to fourth embodiments of the present invention have been described above. However, the present invention is not limited to the above embodiments, and various modifications can be made to the above embodiments without departing from the scope of the present invention. Transformations and substitutions can be added.

  For example, although the movable mold 16 of the first to fourth embodiments is attached to the movable platen 12, it may be attached to the movable platen 12 via a movable side attachment plate. Similarly, the stationary mold 15 may be attached to the stationary platen 11 via a stationary side mounting plate. In this case, for example, the attracting device of the fourth embodiment may be a device that attracts the movable side mounting plate toward the fixed side mounting plate.

  Further, the mold clamping force application units 101 to 301 of the first to third embodiments are provided in the control device 60, but may be provided in a dedicated control device.

10 mold clamping device 11 fixed platen (first fixing member)
12 Movable platen (first movable member)
13 Rear platen (second fixing member)
15 Fixed mold 16 Movable mold 22 Suction plate (second movable member)
37 Electromagnet unit (first clamping force generation mechanism)
49 Electromagnet 60 Control device 70 Mold thickness adjusting device (mold thickness adjusting unit)
71 Mold thickness adjustment motor (drive motor)
71c Brake part 100 2nd mold clamping force generation mechanism 101 Mold clamping force application part 110 Movement suppression part 111 Locking hole 112 Locking pin 210 Spring (biasing part)
410 Spring (attraction device)

Claims (9)

A first fixing member to which a fixed mold is attached;
A first movable member to which a movable mold is attached;
A second movable member that moves with the first movable member;
A second fixed member disposed between the first movable member and the second movable member;
A first mold clamping force generation mechanism for generating a mold clamping force by an attractive force of an electromagnet between the second fixed member and the second movable member;
A second mold clamping force generation mechanism for generating a predetermined mold clamping force in a state where current supply to the first mold clamping force generation mechanism is stopped,
The second mold clamping force generation mechanism is:
A movement suppressing unit that suppresses movement of the second movable member in the mold opening direction;
An injection molding machine comprising: a mold thickness adjusting unit that adjusts an interval between the first movable member and the second movable member.   The injection according to claim 1, wherein the movement suppressing unit suppresses movement of the second movable member in a mold opening direction by locking the second movable member with respect to the second fixed member. Molding machine.   The movement restraining portion causes the second movable member to contact and be attracted to the second fixed member with a residual magnetic flux after stopping the current supply to the first mold clamping force generating mechanism. The injection molding machine according to claim 1, wherein movement of the movable member in the mold opening direction is suppressed. The mold thickness adjusting unit includes a drive motor with a brake,
The injection molding machine according to any one of claims 1 to 3, wherein a mold clamping force generated by the driving motor is maintained by a braking force of the brake. The shift suppressing portion, the injection molding machine of claim 1 including a biasing portion for biasing said first movable member and / or the second mold movable member closing direction. A first fixing member to which a fixed mold is attached;
A first movable member to which a movable mold is attached;
A second movable member that moves with the first movable member;
A second fixed member disposed between the first movable member and the second movable member;
A first mold clamping force generation mechanism for generating a mold clamping force by an attractive force of an electromagnet between the second fixed member and the second movable member;
A first mold clamping force is generated in a state where a gap is formed between the second movable member and the second fixed member and current supply to the first mold clamping force generation mechanism is stopped. 2 mold clamping force generation mechanism,
The second mold clamping force generation mechanism includes an urging unit that urges the first movable member and / or the second movable member in a mold closing direction. A first fixing member to which a fixed mold is attached;
A first movable member to which a movable mold is attached;
A second movable member that moves with the first movable member;
A second fixed member disposed between the first movable member and the second movable member;
A mold clamping force generating mechanism for generating a mold clamping force by an attractive force of an electromagnet between the second fixed member and the second movable member;
A gap is formed between the second movable member and the second fixed member, and the fixed side member and the movable side member are connected in a state where the mold clamping force is generated by the mold clamping force generation mechanism. it is, injection molding machine, characterized in that it comprises a mold clamping force maintaining mechanism for maintaining a predetermined mold clamping force in a state of stopping the current supply to the mold clamping force generating mechanism. The mold clamping force maintaining mechanism includes a movement suppressing unit that suppresses movement of the first movable member or the second movable member in the mold opening direction by connecting the fixed member and the movable member. The injection molding machine according to claim 7. The mold clamping force maintaining mechanism includes a biasing portion that biases the first movable member and / or the second movable member in a mold closing direction by connecting the fixed side member and the movable side member. The injection molding machine according to claim 7 provided.

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