JP5014823B2 - Clamping device - Google Patents

Description

  The present invention relates to a mold clamping device, and more particularly to a mold clamping device that opens and closes a mold by driving a linear motor.

  2. Description of the Related Art Conventionally, in an injection molding machine, resin is injected from an injection nozzle of an injection device, filled into a cavity space between a fixed mold and a movable mold, and solidified to obtain a molded product. ing. A mold clamping device is provided for moving the movable mold relative to the fixed mold to perform mold closing, mold clamping, and mold opening.

  The mold clamping device includes a hydraulic mold clamping device that is driven by supplying oil to a hydraulic cylinder, and an electric mold clamping device that is driven by an electric motor. It is widely used because it has high controllability, does not pollute the surroundings, and has high energy efficiency. In this case, by driving the electric motor, the ball screw is rotated to generate a thrust, and the thrust is expanded by a toggle mechanism to generate a large mold clamping force.

  However, since the electric mold clamping device having the above-described configuration uses a toggle mechanism, it is difficult to change the mold clamping force due to the characteristics of the toggle mechanism, and the responsiveness and stability are improved. The mold clamping force cannot be controlled during molding. Therefore, a mold clamping device is provided in which the thrust generated by the ball screw can be directly used as a mold clamping force. In this case, since the torque of the electric motor and the mold clamping force are proportional, the mold clamping force can be controlled during molding.

  However, in the conventional mold clamping device, the load resistance of the ball screw is low and a large mold clamping force cannot be generated, and the mold clamping force fluctuates due to torque ripple generated in the electric motor. In addition, in order to generate the mold clamping force, it is necessary to constantly supply current to the motor, and the power consumption and heat generation amount of the motor increase. Therefore, it is necessary to increase the rated output of the motor by that amount. The cost of the device becomes high.

Therefore, a mold clamping device using a linear motor for the mold opening / closing operation and utilizing the attractive force of an electromagnet for the mold clamping operation is conceivable (for example, Patent Document 1).
WO05 / 090052 pamphlet

  However, an attractive force acts between the stator (permanent magnet or electromagnet) of the linear motor and the mover (electromagnet or permanent magnet). Therefore, when the stator and the mover are disposed so as to face each other at least in the horizontal direction as in Patent Document 1, the attraction force acts as a moment on the member on which the mover or the stator is disposed. Then, there is a possibility that the member is deformed.

  FIG. 1 is a diagram for explaining a problem due to the influence of the adsorption force between the stator and the mover of the linear motor. In FIG. 1, a state in which the slide base Sb and the frame Fr are deformed by the attractive force of the linear motor 128 including the stator 129 and the movable element 131 arranged so as to face each other in the horizontal direction is indicated by a broken line. ing.

  On the other hand, with respect to the frame Fr, it is desired that deformation due to the weight of the mold clamping device 10 placed thereon is also appropriately suppressed.

  The present invention has been made in view of the above points, and an object of the present invention is to provide a mold clamping device capable of suppressing deformation of a member in which a linear motor for driving mold opening and closing is arranged.

  Therefore, in order to solve the above-described problem, the present invention provides a mold clamping device that includes a linear motor and performs mold opening and closing by a relative movement of the mover with respect to the stator of the linear motor. The mold is placed on the frame on which the mold clamping device is placed so as to face the side surface of the recess formed extending in the mold opening and closing direction in a substantially vertical direction, and the recess is provided with a rib. To do.

  In the present invention, the rib is formed with a recess through which the mover can pass in the mold opening and closing direction.

  According to the present invention, the rib is formed with a recess through which the mover can pass in the mold opening and closing direction when the linear motor is assembled.

  Further, the present invention is characterized in that the stator is disposed on a side surface of the concave portion of the frame so as to extend in the mold opening / closing direction, and the rib is disposed outside the range of the stator. .

  In the mold clamping device as described above, it is possible to suppress the deformation of the member in which the linear motor that drives the mold opening and closing is provided.

  ADVANTAGE OF THE INVENTION According to this invention, the mold clamping apparatus which can suppress a deformation | transformation of the member by which the linear motor which drives mold | die opening / closing is arrange | positioned can be provided.

  Embodiments of the present invention will be described with reference to the drawings.

  First, a mold clamping device of an injection molding machine to which the present invention is applied will be described with reference to FIGS. FIG. 2 is a side view showing a state of the mold apparatus and the mold clamping apparatus when the mold is closed in the embodiment of the present invention. FIG. 3 is a side view showing a state of the mold apparatus and the mold clamping apparatus when the mold is opened in the embodiment of the present invention.

  The mold clamping device 10 shown in FIGS. 2 and 3 is supported on a guide Gd including two rails provided on a frame Fr of the injection molding machine. The stationary platen 11 is placed on the guide Gd and is fixed to the frame Fr and the guide Gd. A rear platen 13 is disposed at a predetermined distance from the fixed platen 11 and facing the fixed platen 11. Between the fixed platen 11 and the rear platen 13, four tie bars 14 (only two are shown in the figure) are installed as connecting members. The movable platen 12 is disposed so as to be movable back and forth in the mold opening / closing direction along the tie bar 14 while being opposed to the fixed platen 11 (movable in the left-right direction in the drawing). For this purpose, a guide hole (not shown) through which the tie bar 14 passes is formed in the movable platen 12.

  In this specification, the mold opening / closing direction, that is, the moving direction of the movable platen 12 is referred to as a horizontal direction, and the direction perpendicular to the moving direction of the movable platen 12 is referred to as a vertical direction.

  A first screw portion (not shown) is formed at the front end portion (right end portion in the figure) of the tie bar 14, and the tie bar 14 is fixed to the fixed platen by screwing and tightening the nut n1 to the first screw portion. 11 is fixed. A guide post 21 having an outer diameter smaller than that of the tie bar 14 is integrally formed at the rear end portion (left end portion in the drawing) of each tie bar 14. The guide post 21 extends from the rear end surface (left end surface in the drawing) of the rear platen 13 so as to protrude rearward. A second screw portion (not shown) is formed in the vicinity of the rear end surface of the rear platen 13 of each guide post 21, and the fixed platen 11 and the rear platen 13 are screwed into the second screw portion with a nut n 2. It is fixed by tightening. Although the guide post 21 is formed integrally with the tie bar 14, the guide post 21 may be formed separately from the tie bar 14.

  A fixed mold 15 is fixed to the fixed platen 11, and a movable mold 16 is fixed to the movable platen 12. A mold apparatus 19 is configured by the fixed mold 15 and the movable mold 16. As the movable platen 12 advances and retreats, the movable mold 16 is moved with respect to the fixed mold 15 to perform mold closing, mold clamping, and mold opening. When the mold clamping is performed, a cavity space is formed between the fixed mold 15 and the movable mold 16, and resin as a molding material injected from the injection nozzle 18 of the injection device 17 is filled into the cavity space. The

  An attracting plate 22 as a magnetic body disposed in parallel with the movable platen 12 is disposed behind the rear platen 13 so as to be able to advance and retreat along each guide post 21 and is guided by the guide post 21. In the suction plate 22, guide holes 23 through which the guide posts 21 pass are formed at positions corresponding to the respective guide posts 21. The guide hole 23 includes a large-diameter portion 24 opened on the front end surface (right end surface in the drawing) and a small-diameter portion 25 connected thereto. The large diameter portion 24 accommodates the nut n2. The small-diameter portion 25 opens at the rear end surface of the suction plate 22 and has a sliding surface on which the guide post 21 slides. The suction plate 22 is guided by the guide post 21, but the suction plate 22 can be guided not only by the guide post 21 but also by the guide Gd. Alternatively, it is possible to guide only by the guide Gd without using the guide post 21.

  In order to move the movable platen 12 back and forth, a linear motor 28 is disposed between the suction plate 22 connected to the movable platen 12 and the frame Fr as a mold opening / closing drive unit.

  When the movable platen 12 moves forward (moves in the right direction in the figure) by driving the linear motor 28 and the movable mold 16 comes into contact with the fixed mold 15, the mold closing is completed. An electromagnet unit 37 as a mold-clamping drive unit is disposed between the rear platen 13 and the suction plate 22 so that mold clamping can be performed following mold closing. A rod 39 that connects the movable platen 12 and the suction plate 22 extends through the rear platen 13 and the suction plate 22. The rod 39 advances and retracts the movable platen 12 in conjunction with the advance and retreat of the suction plate 22 when the mold is closed and opened, and transmits the mold clamping force generated by the electromagnet unit 37 to the movable platen 12 when the mold is clamped. The mold clamping device 10 is configured by the frame Fr, 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.

  The electromagnet unit 37 includes an electromagnet 49 disposed on the rear platen 13 side, and an attracting portion 51 disposed on the attracting plate 22 side. Two grooves 45 serving as coil arrangement portions having a rectangular cross-sectional shape extending in the horizontal direction are formed in parallel to each other at a predetermined portion of the rear end surface of the rear platen 13, that is, slightly above and below the rod 39. Yes. A core 46 having a rectangular cross-sectional shape is formed between the grooves 45, and a yoke 47 is formed in a portion other than the core 46 of the rear platen. A coil 48 is wound around the core 46.

  Further, as a predetermined portion of the front end surface of the suction plate 22, a suction portion 51 is provided in a portion surrounding the rod 39 in the suction plate 22 and facing the electromagnet 49. The core 46 and the yoke 47 of the rear platen 13 and the suction plate 22 are made of electromagnetic laminated steel plates formed by laminating thin plates made of ferromagnetic materials. In addition, an electromagnet 49 is provided separately from the rear platen 13 and an adsorbing portion 51 is provided separately from the adsorption plate 22, but an electromagnet is formed as a part of the rear platen 13 and adsorbed as a part of the adsorption plate 22. A part can also be formed. Further, the electromagnetic laminated steel plate is not necessarily used, and the core 46 and the yoke 47 may be formed using an iron core made of the same member. In this way, the distance between the gaps can be set with higher accuracy.

  Therefore, in the electromagnet unit 37, when a current is supplied to the coil 48 in the groove 45, the electromagnet 49 is excited and the attracting part 51 is attracted to generate a mold clamping force.

  The rod 39 is connected to the suction plate 22 at the rear end portion (left end portion in the figure), and is connected to the movable platen 12 at the front end portion. The rod 39 moves forward when the suction plate 22 moves forward when the mold is closed, whereby the movable platen 12 moves forward. Further, the rod 39 moves backward when the suction plate 22 moves backward (moves leftward in the figure) when the mold is opened, and thereby the movable platen 12 moves backward.

  For this purpose, a hole 41 for penetrating the rod 39 is provided in the central portion of the rear platen 13. In addition, a hole 42 for penetrating the rod 39 is formed in the central portion of the suction plate 22. Further, a bearing member Br1 such as a bush that slidably supports the rod 39 is disposed facing the opening at the front end of the hole 41. A screw 43 is formed at the rear end of the rod 39, and a nut 44 as a mold thickness adjusting mechanism that is rotatably supported by the suction plate 22 is screwed into the screw 43.

  When the mold closing is completed, the suction plate 22 is close to the rear platen 13, and a gap (gap) δ is formed between the rear platen 13 and the suction plate 22. If the gap δ becomes too small or too large, the adsorbing portion 51 cannot be adsorbed sufficiently and the mold clamping force will be reduced. The optimum value (distance or dimension) of the gap δ changes as the thickness of the mold apparatus 19 changes.

  Therefore, a large-diameter gear (not shown) is formed on the outer peripheral surface of the nut 44, and a mold thickness adjusting motor (not shown) is disposed on the suction plate 22 as a drive unit for adjusting the mold thickness. A small-diameter gear attached to the output shaft of the adjustment motor is meshed with a gear formed on the outer peripheral surface of the nut 44.

  When the mold thickness adjusting motor is driven in accordance with the thickness of the mold apparatus 19 and the nut 44 as the mold thickness adjusting mechanism 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 changed. By adjusting the position of the suction plate 22 with respect to the fixed platen 11 and the movable platen 12, the gap δ can be set to an optimum value. That is, the mold thickness is adjusted by changing the relative positions of the movable platen 12 and the suction plate 22.

  This adjustment of the mold thickness is to roughly adjust the distance of the gap δ accompanying the change in the mold thickness. For example, fine adjustment in units of 0.1 mm can change the position of the suction plate 22 on the slide base Sb, This is done by changing the position of the rear platen 13 on the guide Gd. In the mold clamping device 10, the suction plate 22 is attached to a mounting plate 27 that is vertically installed from the slide base Sb, and the thickness of the shim sandwiched between the suction plate 22 and the mounting plate 27 is adjusted. Thus, the distance of the gap δ is finely adjusted. The mounting plate 27 has ribs 27a, and is configured to maintain the verticality without falling down on the mounting surface of the mounting plate 27 even when a reaction force of the mold clamping force acts on the mounting plate 27. Has been.

  In order to maintain the parallelism between the electromagnet and the suction plate, it is preferable to sandwich a shim having the same size as the entire surface of the electromagnet or the suction plate, but a shim having such a uniform thickness is used. It ’s difficult. Therefore, for example, when the vicinity of the four corners of the substantially quadrilateral suction plate is tightened with bolts, small shims are sandwiched only in the vicinity of the four places to be tightened. In such a case, there is a possibility that a gap is formed in a portion where the shim is not sandwiched and the suction plate is deformed to deteriorate the flatness or the parallelism with respect to the base.

  A mold thickness adjusting device is configured by the mold thickness adjusting motor, the gear, the nut 44, the rod 39, and the like. In addition, a rotation transmitting portion that transmits the rotation of the mold thickness adjusting motor to the nut 44 is constituted by the gear. The nut 44 and the screw 43 constitute a movement direction conversion unit, and the rotation movement of the nut 44 is converted into a straight movement of the rod 39 in the movement direction conversion unit.

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

  First, when the mold is closed, a current is supplied to a coil (a coil 35 described later) of the linear motor 28 in the state shown in FIG. Thereby, the linear motor 28 is driven, the movable platen 12 is advanced together with the suction plate 22, and the movable mold 16 is brought into contact with the fixed mold 15 as shown in FIG. 2. At this time, as a result of finely adjusting the position of the suction plate 22 using a shim between the rear platen 13 and the suction plate 22, that is, between the electromagnet 49 and the suction portion 51, a target mold clamping force F is obtained. Such an optimal gap (gap) δ is formed. Note that the force required for mold closing is sufficiently smaller than the mold clamping force.

  Subsequently, an electric current is supplied to the coil 48 to attract the attracting portion 51 of the attracting plate 22, which is a magnetic material, by the attracting force of the electromagnet 49. As a result, the suction force is transmitted as a mold clamping force to the movable platen 12 via the suction plate 22 and the rod 39, and the mold clamping is performed.

  Further, the value of the current supplied to the coil 48 is determined so that the mold clamping force becomes the target set value, and the current is supplied to the coil 48 to perform mold clamping. While mold clamping is performed, the 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 solidified, the current supply to the coil 48 is stopped in the state shown in FIG. In this case, even if the current supply to the coil 48 is stopped, the magnetism remains in the attracting part 51, so that a current is supplied in the opposite direction to when the coil 48 is clamped and remains in the attracting part 51. The magnetism is removed. Subsequently, a current in the reverse direction is supplied to the coil of the linear motor 28. As a result, the linear motor 28 is driven, the movable platen 12 is moved backward, and the movable mold 16 is moved to the backward limit position as shown in FIG.

  In the mold clamping apparatus 10 having the above-described configuration, the work of adjusting the distance of the gap (gap) δ by sandwiching the shim between the mounting plate 27 and the suction plate 22 requires time and labor. Further, since the distance that can be adjusted depends on the thickness of the shim, there is a problem that it is difficult to adjust with high accuracy. Further, if a gap is generated between the attachment plate 27 and the suction plate 22, the magnetic circuit composed of the suction plate 22 and the attachment plate 27 fluctuates, and the mold clamping force cannot be controlled with high accuracy.

  Therefore, in the mold clamping apparatus 10 according to the present embodiment, the opposing surfaces of the rear platen 13 and the suction plate 22 constituting the electromagnet (that is, the opposing surfaces that form the gap δ) are slightly inclined, so that the rear platen 13 and the suction plate 22 The distance of the gap δ is substantially adjusted by moving both or one of them in the vertical direction. Based on the ratio determined by the inclination angle, the vertical movement distance is reduced to the horizontal movement distance (that is, the adjustment distance of the gap δ), so that fine adjustment can be easily performed.

  Next, the structure of the linear motor 28 in the mold clamping device 10 and the frame Fr designed according to the structure of the linear motor 28 will be described in detail with reference to FIGS. FIG. 4 is a schematic side view of a mold clamping device for explaining the structures of the linear motor and the frame. FIG. 5 is a view of the suction plate and the frame as viewed from the rear (the direction indicated by the arrow A in FIG. 4). 6 is a cross-sectional view taken along the line BB in FIGS. 4 and 5. FIG. 7 is a perspective view of the frame.

  As shown in FIG. 5 and the like, the slide base Sb is supported by the guide Gd via the guide base Gb on both sides thereof, and extends in the extending direction of the guide Gd. Therefore, as shown in FIG. 3, a space 81 through which the guide base Gb and the slide base Sb pass is formed at the lower end of the rear platen 13. Here, the rear platen 13 is fixed to the frame Fr by legs (not shown) so as to straddle the slide base Sb.

  The slide base Sb is formed with a convex portion (magnet base 71) extending downward from the bottom surface thereof and extending in the moving direction (mold opening / closing direction) of the suction plate 22. In FIG. 5 (in a direction orthogonal to the mold opening / closing direction), the magnet base 71 has two side surfaces that are substantially perpendicular to the slide base Sb (horizontal plane) and parallel to the mold opening / closing direction. The both side surfaces are formed symmetrically with respect to the vertical axis Z. The vertical axis Z is a vertical axis that passes through the central axis of the rod 39 and bisects the suction plate 22 symmetrically.

  The frame Fr includes two square pipes 91, leg portions 92, a bottom plate 93, ribs 94, and the like. The two square pipes 91 respectively extend in parallel with the mold opening / closing direction so as to correspond to the guide Gd. In FIG. 5, the cross section of the square pipe has a rectangular shape. Therefore, the side surface of the square pipe 61 forms a plane that is substantially perpendicular to the horizontal plane and parallel to the moving direction (mold opening / closing direction) of the suction plate 22.

  A base plate 95 is disposed on the upper surface of each square pipe 91 as a plate-like member for laying the guide Gd. The square pipe 91 is supported by the leg portion 92. The leg portions 92 are columnar members, stand up at predetermined intervals along the extending direction of the square pipe 91, and support the square pipe 91.

  Since the two square pipes 91 extend in parallel, a groove space (concave part) in which the magnet base 71 is received and the linear motor 28 is disposed is formed between the square pipes 91.

  By the way, in order to support the weight of the mold clamping device 10, the strength of the frame Fr is insufficient if the two square pipes 91 and the like extend in parallel in a separated state. Further, since an attracting force due to electromagnetic force acts between the mover and the stator of the linear motor 28, the frame Fr and the magnet base 71 are attracted to each other, and sufficient strength is required. Therefore, a bottom plate 93 and a rib 94 are provided to ensure the strength of the frame Fr. The bottom plate 93 is disposed so as to close the bottom of the groove space formed by the two square pipes 91. The rib 94 is disposed between the two square pipes 91 so as to form a wall substantially orthogonal to the extending direction (mold opening / closing direction) in the groove space. However, the wall does not necessarily have to be orthogonal to the mold opening / closing direction.

  In such a structure, the linear motor 28 includes a stator 29 disposed on the frame Fr and a mover 31 disposed on the slide base Sb.

  The mover 31 is disposed on both side surfaces of the magnet base 71 so as to be movable along the stator 29 over a predetermined range. As shown in FIG. 6, the mover 31 includes a core 34 formed so that a plurality of magnetic pole teeth 33 protrude toward the stator 29 at a predetermined pitch, and a coil wound around each magnetic pole tooth 33. 35. The magnetic pole teeth 33 are formed in parallel to each other in a direction perpendicular to the moving direction of the suction plate 22.

  The stator 29 is disposed on two side surfaces facing each other in the two square pipes 91 (that is, on the side surface facing the side surface of the magnet base 71 of the slide base Sb in each of the square pipes 91), and at least within the moving range of the suction plate 22. Correspondingly disposed. The stator 29 includes a core and a permanent magnet (not shown) formed to extend on the core. The permanent magnet is formed by magnetizing the N and S magnetic poles alternately and at the same pitch as the magnetic pole teeth 33. A magnetic thin plate 96 as a moment canceller is disposed between the stator 29 and the square pipe 91. The thin plate 96 has, for example, an L-shaped cross section along the square pipe 91 and is fixed to the base plate 95 with bolts 97. As shown in FIG. 6, the thin plate 96 is disposed at least corresponding to the range in which the stator 29 is disposed.

  Thus, the mover 31 and the stator 29 face each other in the substantially vertical direction. In the present embodiment, two linear motors 28 are arranged symmetrically with respect to the vertical axis Z.

  When the length of the stator 29 of the linear motor 28 is Lp, the length of the movable element 31 is Lm, and the stroke of the suction plate 22 (movable platen 12) is Lst, the length Lm is the maximum by the linear motor 28. It is set according to the driving force. The length Lp is set so as to satisfy the relationship Lp> Lm + Lst.

  When a predetermined current is supplied to the coil 35 to drive the two linear motors 28, the movers 31 of both linear motors 28 are moved forward and backward. Along with this, the slide base Sb, the suction plate 22 fixed to the slide base Sb, and the movable platen 12 connected to the suction plate 22 by the rod 39 are moved forward and backward to perform mold closing and mold opening. At this time, the direction and magnitude of each of the attracting forces (the attracting force between the stator 29 and the movable element 31) of the two linear motors 28 are symmetrical with respect to the vertical axis Z in a plane orthogonal to the mold opening / closing direction. It is controlled as follows.

  In addition, although the permanent magnet is provided in the stator 29 and the coil 35 is provided in the mover 31, the coil may be provided in the stator and the permanent magnet may be provided in the mover. In this case, since the coil does not move when the linear motor 28 is driven, wiring for supplying power to the coil can be easily performed.

  In FIG. 5, arrows a <b> 3 and a <b> 4 indicate an attractive force acting on the magnet base 71 by the magnetic force generated between the stator 29 and the movable element 31 when the linear motor 28 is driven. The attraction force acts on the back surface of the magnet base 71 by the two linear motors 28. Here, the directions and magnitudes of the respective attractive forces are substantially the same. Therefore, the adsorption forces a3 and a4 are almost offset. Therefore, deformation of the slide base Sb is reduced.

  On the other hand, the influence of the magnetic force generated between the stator 29 and the mover 31 on the frame Fr is absorbed by the thin plate 96. That is, when the magnetic thin plate 96 is deformed, the magnetic force is absorbed, and the influence of the magnetic force on the frame Fr (square pipe 91) is reduced. Thereby, deformation of the frame Fr (square pipe 91) is reduced. However, since the attracting force due to the magnetic force is strong, even if it is reduced by the thin plate 96, the force still acts in the direction attracting the two square pipes 91 (on the magnet base 71 side). Furthermore, the weight of the mold clamping device 10 placed on the frame Fr also works. Therefore, in the present embodiment, ribs 94 are provided between the square pipes 91 so that the frame Fr can sufficiently counter the force and weight.

  The rib 94 is preferably disposed outside the range of the stator 29 of the linear motor 28. This is because the rib 94 divides the stator 29 when it is disposed within the range of the stator 29 and affects the output of the linear motor 28. In order to prevent the stator 29 from being divided, it is conceivable to dispose the rib 94 on the lower side of the stator 29. In this case, however, the rib 94 must be made small, and the viewpoint of securing the strength of the frame Fr is considered. Is not efficient. Further, the rib 94 is influenced by the magnetic force of the linear motor 28, and the output of the linear motor 28 may be affected.

  Incidentally, the rib 94 has a recess. This is in consideration of convenience in assembling the mold clamping device 10. That is, when the stator 29 and the mover 31 are disposed so as to face each other in the substantially vertical direction as in the present embodiment, the slide base Sb (magnet plate 71) on which the mover 31 is disposed is provided. If the movable element 31 can be arranged at a location where the stator 29 and the movable element 31 do not interfere with each other or where the interference is small, the linear motor 28 is easily assembled. Because it becomes possible. If the linear motor 28 is to be assembled by lowering the mover 31 from above the place where the stator 29 is disposed, the mover 31 and the stator are moved while the slide base Sb is being lowered. The slide base Sb is tilted by the strong magnetic force between the linear motor 28 and the assembly work of the linear motor 28 becomes difficult.

  Therefore, the recess formed in the rib 94 is sufficient for the magnet plate 71 and the movable element 31 disposed on the magnet plate 71 to pass through the rib 94 when the slide base Sb is slid from the rear of the frame Fr. Must have width and height.

  As described above, according to the mold clamping device 10 of the embodiment of the present invention, the deformation of the slide base Sb due to the magnetic force of the linear motor 28 can be reduced. Therefore, the accuracy of linearity of the linear motor 28 can be improved, and the possibility of molding defects can be reduced.

  Furthermore, in the mold clamping device 10 according to the embodiment of the present invention, two linear motors 28 are used. Therefore, compared with the case where only one linear motor 28 is provided, the magnetic force generated in one linear motor 28 to obtain the same thrust can be almost halved. Also from this point, the deformation of the frame Fr and the slide base Sb can be effectively reduced.

  Further, when the stator 29 and the mover 31 of the linear motor 28 are opposed to each other in the vertical direction, a concave groove space is formed in the frame Fr. In the mold clamping device 10 of the present embodiment, the groove space is formed in the groove space. Since the rib 94 is provided, it is possible to appropriately suppress the deterioration of the strength of the frame Fr due to the formation of the groove space.

  The two square pipes 91 and the bottom plate 93 may be configured by bending a single metal plate so that a groove space is formed between two convex portions (portions of the square pipe 91). Good.

  As mentioned above, although the Example of this invention was explained in full detail, this invention is not limited to such specific embodiment, In the range of the summary of this invention described in the claim, various deformation | transformation・ Change is possible.

It is a figure for demonstrating the problem by the influence of the attraction | suction force of the stator and mover of a linear motor. It is a side view which shows the state at the time of the mold closing of the metal mold apparatus and mold clamping apparatus in embodiment of this invention. It is a side view which shows the state at the time of the mold opening of the metal mold | die apparatus and mold clamping apparatus in embodiment of this invention. It is a schematic diagram of the side surface of the mold clamping apparatus for demonstrating the structure of a linear motor and a flame | frame. It is the figure which looked at the adsorption plate and the frame from back. It is BB sectional drawing of FIG.4 and FIG.5. It is a perspective view of a frame.

Explanation of symbols

10 mold clamping device 11 fixed platen 12 movable platen 13 rear platen 14 tie bar 15 fixed mold 16 movable mold 17 injection device 18 injection nozzle 19 mold device 21 guide post 22 suction plate 23 guide hole 24 large diameter portion 25 small diameter portion 27 support Plate 27a Rib 28 Linear motor 29 Stator 31 Movable element 33 Magnetic pole teeth 34 Core 35 Coil 37 Electromagnet unit 39 Rod 41, 42 Hole 43 Screw 44 Nut 45 Coil arrangement part 46 Core 47 Yoke 48 Coil 49 Electromagnet 51 Adsorption part 71 Magnet Base 81 Space 91 Square pipe 92 Leg 93 Bottom plate 94 Rib 91 Thin plate 92 Bolt Br1 Bearing member Gb Guide base Gd Guide Fr Frame n1, n2 Nut Sb Slide base

Claims (3)

A mold clamping device comprising a linear motor, wherein the mold is opened and closed by relative movement of a mover with respect to a stator of the linear motor,
The movable element is arranged to face a side surface of a recess formed to extend in a mold opening / closing direction on a frame on which the mold clamping device is placed, in a substantially vertical direction,
The stator is arranged to extend in the mold opening and closing direction on the side surface of the recess of the frame,
A mold clamping device , wherein a rib is disposed outside the range of the stator in the recess.   The mold clamping device according to claim 1, wherein the rib is formed with a recess through which the movable element can pass in the mold opening / closing direction.   3. The mold clamping apparatus according to claim 2, wherein a recess is formed in the rib through which the movable element can pass in the mold opening / closing direction when the linear motor is assembled.

Images