JP2011079204A - Mold clamping device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To miniaturize the contour of a mold clamping device by integrally forming a reinforcing member with a fixing member and disposing them in a lattice shape on the rear face. <P>SOLUTION: The mold clamping device clamps the molds using an electromagnet, and has a coil holding member having a coil holding face holding a coil of the electromagnet, an attracting member having an attracting face opposing to the coil holding face and attracted by the electromagnet, and the reinforcing member made of a magnetic body reinforcing the attraction plate. The reinforcing member is disposed to include a portion corresponding to at least a part of the coil at a part of the rear side face to the attracting face in the attraction plate. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a mold clamping device.

  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 can be considered (for example, Patent Document 1).

JP 2008-246778 A

  However, in the mold clamping device described in Patent Document 1, it is necessary to give the suction plate 22 a sufficient thickness in order to avoid magnetic saturation. In addition, the suction plate 22 is required to have a sufficient thickness in order to ensure strength for preventing deflection due to the suction force. For this reason, there is a problem that the entire mold clamping device is enlarged.

  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 reducing the size of the outer shape.

  Accordingly, in order to solve the above-described problem, the present invention provides a mold clamping device that performs a clamping operation using an electromagnet, a coil holding member having a coil holding surface for holding a coil of the electromagnet, and a coil holding surface. An adsorbing member facing and adsorbed by the electromagnet; and a magnetic reinforcing member that reinforces the adsorbing member, wherein the reinforcing member is on the back side of the adsorbing surface of the adsorbing member. It arrange | positions so that the part corresponding to at least one part of the said coil may be included in a part of surface.

  In the present invention, the portion corresponding to at least a part of the coil is a portion having a relatively high magnetic flux density in the portion corresponding to the coil on the back surface.

  In the present invention, the reinforcing member and the adsorption member are integrally formed.

  Further, the present invention provides a slide member that is fixed to the mold opening / closing drive unit and moves in the mold opening / closing direction by driving the mold opening / closing drive unit, and is fixed to a horizontal surface of the slide member, and on the back surface of the adsorption member A fixing member that fixes the suction member to the slide member by being fixed to the suction member at a portion extending in a vertical direction, and the reinforcing member and the fixing member are integrally formed. .

  In the present invention, the reinforcing member and the fixing member are arranged in a lattice pattern on the back surface.

  According to the present invention, it is possible to reduce the size of the outer shape of the mold clamping device.

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 1st embodiment. 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 1st embodiment. It is a figure which shows the example of the magnetic flux loop in the cross section of the conventional adsorption | suction board and a rear platen. It is a figure which shows magnetic flux density distribution by the FEM analysis of the cross section of the conventional adsorption | suction board and rear platen at the time of mold clamping. It is a figure which shows the example of arrangement | positioning of the adsorption | suction board and reinforcement member in 1st embodiment. It is a figure which shows the example of arrangement | positioning of the adsorption | suction board and reinforcement member in 2nd embodiment. It is a figure which shows the example of arrangement | positioning of the adsorption | suction board and reinforcement member in 3rd embodiment. It is a figure which shows the example of arrangement | positioning of the adsorption | suction board and reinforcement member in 4th embodiment. It is a figure which shows the example of arrangement | positioning of the adsorption | suction board and reinforcement member in 5th embodiment. It is a figure which shows the example of arrangement | positioning of the adsorption | suction board and reinforcement member in 6th Embodiment. It is a figure which shows the example of arrangement | positioning of the suction plate and reinforcement member in 7th Embodiment. It is a figure which shows the example of arrangement | positioning of the adsorption | suction board and reinforcement member in 8th Embodiment. It is a figure which shows the example of arrangement | positioning of the adsorption | suction board and reinforcement member in 9th Embodiment. It is a figure which shows the example of arrangement | positioning of the adsorption | suction board and reinforcement member in 10th Embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  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. 1 is a side view showing a state of the mold apparatus and the mold clamping apparatus in the first embodiment when the mold is closed. FIG. 2 is a side view showing a state when the mold device and the mold clamping device of the first embodiment are opened.

  The mold clamping device 10 shown in FIGS. 1 and 2 is supported on a guide Gd including two rails provided on a frame Fr of an 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 serving as a coil holding member is disposed at a predetermined interval 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

  A magnetic attracting plate 22 disposed in parallel with the movable platen 12 is disposed behind the rear platen 13 so as to be movable back and forth along the guide posts 21 and guided by the guide posts 21. The suction plate 22 as the suction member is fixed to the slide base Sb as the slide member by a fixing member 53 disposed on the rear end surface (the back surface (rear surface) with respect to the surface facing the rear end surface of the rear platen 13). The That is, in the present embodiment, the suction plate 22 is not directly fixed to the slide base Sb. Specifically, a space 82 is formed between the lower end surface of the suction plate 22 and the slide base Sb. However, the lower end surface of the suction plate 22 may be directly fixed to the slide base Sb.

  A reinforcing member 54 is disposed on the rear end surface of the suction plate 22 so as to extend in the horizontal direction. Thinning of the suction plate 22 is realized while maintaining the performance of the suction plate 22 by the reinforcing member 54. Details of the suction plate 22 and the reinforcing member 54 will be described later.

  The suction plate 22 is further formed with guide holes 23 through which the guide posts 21 penetrate at locations corresponding to the 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.

  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. The linear motor 28 includes a stator 29, a mover 31 and the like. The stator 29 is disposed on the frame Fr in parallel with the guide Gd and corresponding to the moving range of the suction plate 22. The mover 31 is formed over a predetermined range so as to face the stator 29 and is fixed to the slide base Sb.

  As shown in FIG. 2, the slide base Sb is supported on the guide Gd on both sides thereof, and supports the movable element 31 so as to be movable along the stator 29. The slide base Sb covers the upper surface of the mover 31 and extends in the extending direction of the guide Gd. For this purpose, leg portions 13a forming spaces 81 through which the guide base Gb and the slide base Sb pass are provided on both sides at the lower end of the rear platen 13.

  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.

  The mover 31 includes a core 34 protruding toward the stator 29 and having a plurality of magnetic pole teeth 33 formed at a predetermined pitch, and a coil 35 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 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.

  Therefore, when a predetermined current is supplied to the coil 35 and the linear motor 28 is driven, the mover 31 is 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.

  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.

  When the movable platen 12 moves forward (moves in the right direction in the figure) 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 as a coil arrangement portion 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. Further, a hole 42 for connecting 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.

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

  First, when the mold is closed, a current is supplied to the coil 35 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. At this time, an optimum gap (gap) δ is obtained between the rear platen 13 and the suction plate 22, that is, between the electromagnet 49 and the suction portion 51 so as to obtain the target mold clamping force F. 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 35. Thereby, the linear motor 28 is driven, the movable platen 12 is moved backward, and as shown in FIG. 2, the movable mold 16 is moved to the backward limit position, and the mold opening is performed.

  In the present embodiment, the linear motor 28 is arranged as the first drive unit. However, instead of the linear motor 28, an electric motor, a hydraulic cylinder or the like is arranged. Can do. When the motor is used, the rotational rotational motion generated by driving the motor is converted into a linear motion by a ball screw as a motion direction conversion unit, and the movable platen 12 is advanced and retracted.

  Next, the suction plate 22 will be described in detail. FIG. 3 is a diagram illustrating an example of a magnetic flux loop in a cross section of a conventional suction plate and rear platen. The suction plate 22a and the rear platen 13a shown in the figure are conventional suction plates or rear platens (before downsizing of the mold clamping device 10). Therefore, at least the suction plate 22a is thicker than the suction plate 22 in the present embodiment.

  As can be seen from the figure, the magnetic flux loop L does not reach the vicinity of the rear end of the suction plate 22. Then, if only considering securing the magnetic flux loop L as usual, it is considered sufficient that the suction plate 22a has a thickness indicated by w, for example.

  FIG. 4 is a diagram showing a magnetic flux density distribution by FEM analysis of the cross section of the conventional suction plate and the rear platen during mold clamping. In the figure, the height of the magnetic flux density is in a relationship of distribution B0 <B1 <B2 <B3 <B4 <B5 <B6. That is, the magnetic flux density is higher in the distribution B6 than in the distribution B0. As is well known, the smaller the magnetic flux density, the smaller the contribution to the attractive force. In the figure, for the distribution B2 and below (B2, B1, B3), the contribution to the attractive force is negligible. If it does so, even if it considers distribution of magnetic flux density, it turns out that the rear end surface vicinity (part after the thickness of w from a front end surface) does not contribute so much with respect to adsorption power. However, when the thickness of the suction plate 22a is set to w, a portion (for example, the region A) belonging to the distribution B3 is greatly shaved. As a result, magnetic saturation may occur.

  Further, when the thickness of the suction plate 22a is set to w, the strength of the suction plate 22a is deteriorated. As a result, the suction plate 22 cannot withstand the suction force and may be bent. The reason why the suction plate 22a has the conventional thickness is to secure strength against bending.

  Therefore, in the present embodiment, a configuration as shown in FIG. 5 is adopted in order to eliminate the above disadvantages caused by making the suction plate 22 thin.

  FIG. 5 is a diagram illustrating an arrangement example of the suction plate and the reinforcing member in the first embodiment. In FIG. 5, the same parts as those in FIG. 1 or 2 are denoted by the same reference numerals, and the description thereof is omitted as appropriate.

  In the figure, (A) is a front view of the suction plate 22 viewed from the rear end side. (B) is a perspective view of the suction plate 22 and the rear platen 13. As shown in the figure, two fixing members 53 and a reinforcing member 54 are fixed to the rear end surface of the suction plate 22.

  The fixing member 53 fixes the suction plate 22 to the slide base Sb, and prevents the suction plate 22 from collapsing due to the suction force and the suction plate 22 from being bent in the vertical direction (vertical direction) (for example, Iron square wood). Accordingly, the fixing member 53 is fixed to the slide base Sb with appropriate strength at the lower end portion thereof. The fixing member 53 extends in the vertical direction on the rear end surface of the suction plate 22 and is fixed to the suction plate 22.

  On the other hand, the reinforcing member 54 is a member (for example, a square member or a plate member of a magnetic material) for reinforcing deterioration in strength of the suction plate 22 due to the thinning of the suction plate 22. Strengthening the deterioration of the strength means securing the strength against the bending of the suction plate 22 in the horizontal direction by the suction force acting on the suction plate 22. Therefore, the reinforcing member 54 is disposed so as to extend in the horizontal direction on the rear end surface of the suction plate 22 and is fixed to the suction plate 22. That is, the reinforcing member 54 is disposed in a direction that intersects (intersects) the fixing member 53. By intersecting the reinforcing member 54 and the fixing member 53, it is possible to appropriately ensure strength (strength for preventing bending) in all directions (vertical direction, horizontal direction, and other directions) with respect to the suction plate 22. it can. Note that the fixing member 53 and the reinforcing member 54 do not necessarily have to be arranged so as to intersect at a right angle. For example, the two fixing members 53 may be arranged in a square shape.

  The reinforcing member 54 also functions as a member for preventing a decrease in the suction force due to the thinning of the suction plate 22 (maintaining a suction force equivalent to that of the suction plate 22a), in other words, a part of the suction plate 22. It is also a member. That is, “reinforcement” by the reinforcing member 54 means not only reinforcement of strength against bending but also reinforcement of adsorption power. Therefore, the reinforcing member 54 is a magnetic body, and is disposed so as to complement the region A (see FIG. 4) that is lost from the suction plate 22 due to the thinning. More specifically, the reinforcing member 54 is disposed so as to include a portion corresponding to the coil 48 (groove 45) in a part of the rear end surface of the suction plate 22. As shown in FIG. 5A, the portion corresponding to the coil 48 is a portion corresponding to the coil 48 on the receding surface of the suction plate 22 when the suction plate 22 is viewed from the rear end face. It is. By arranging the magnetic reinforcing member 54 at such a position, the occurrence of magnetic saturation is appropriately avoided, and a reduction in the attractive force is prevented.

  However, the material of the reinforcing member 54 is not necessarily the same as that of the suction plate 22. For example, if the thickness of the suction plate 22 is w shown in FIG. 4 and the reinforcing member 54 is disposed so as to include the region A, the region where the reinforcing member 54 is located is the region of the suction plate 22. On the other hand, the magnetic flux density is relatively low. The volume of the reinforcing member 54 is smaller than that of the suction plate 22. Then, it can be said that the reinforcing member 54 has a significantly smaller contribution to the suction force than the suction plate. Therefore, the reinforcing member 54 may be a magnetic body having a lower magnetic permeability than the adsorption plate 22.

  Further, the reinforcing member 54 and the suction plate 22 may be formed integrally. In this case, the reinforcing member 54 is made of the same material as the suction plate 22. The fixing member 55 may also be formed integrally with the reinforcing member 54 or the suction plate 22. By forming the members integrally, the number of members can be reduced, and the productivity of the members can be improved. In addition, the assembly man-hours of the members can be reduced.

  As described above, in the mold clamping device 10 of the first embodiment, it is possible to secure the strength of the suction plate 22 and maintain the suction force while reducing the thickness of the suction plate 22. As a result, the entire mold clamping device 10 can be reduced in size and weight while maintaining the conventional performance with respect to the suction plate 22.

  Next, a second embodiment will be described. In the second and subsequent embodiments, portions that are basically different from the embodiments described so far will be described. Therefore, with respect to each embodiment, the contents described in the other embodiments are effective within the obvious range.

  FIG. 6 is a diagram illustrating an arrangement example of the suction plate and the reinforcing member in the second embodiment. In FIG. 6, the same parts as those in FIG. 5 are denoted by the same reference numerals, and the description thereof will be omitted as appropriate.

  The reinforcing member 54 shown in the figure has a rectangular cross section in a portion corresponding to the core 46 between the two fixing members 53 (a portion not corresponding to the coil 48 between the two fixing members 53). A recess or a hole (hereinafter referred to as “hole H1”) is provided. As a result, the weight of the reinforcing member 54 is reduced compared to the first implementation. However, the portion where the reinforcing member 54 is disposed is common to the first embodiment in that it is a portion including a portion corresponding to the coil 48 in a part of the rear end surface of the suction plate 22.

  Even when the hole H1 is formed in the reinforcing member 54, the strength of the suction plate 22 can be sufficiently ensured. In addition, the influence on the suction force due to the formation of the hole H1 is small enough to be ignored in actual operation. That is, the hole H1 is a portion related to the distributions B1 and B2 in FIG. As described above, the portions related to the distributions B1 and B2 are so small that the contribution to the adsorption force can be ignored. Therefore, the portion where the hole H1 is formed is small enough to ignore the contribution to the attractive force.

  As described above, according to the second embodiment, the weight of the reinforcing member 54 can be reduced while maintaining the effects of the first embodiment. As a result, the weight of the entire mold clamping device 10 can be further reduced. Note that the cross section of the hole H1 is not necessarily rectangular. For example, the corner portion of the hole H1 may have R (a curve).

  The recess or hole in the reinforcing member 54 may be formed in a portion different from the hole H1. FIG. 7 is a diagram illustrating an arrangement example of the suction plate and the reinforcing member in the third embodiment. 7, the same parts as those in FIG. 5 or FIG. 6 are denoted by the same reference numerals, and the description thereof is omitted as appropriate.

  The reinforcing member 54 shown in FIG. 7 has a recess or a hole (hereinafter referred to as “hole H2”) in a portion that does not correspond to the coil 48 outside the fixing member 53. As a result, the weight of the reinforcing member 54 is reduced compared to the first implementation. However, the portion where the reinforcing member 54 is disposed is common to the first embodiment in that it is a portion including a portion corresponding to the coil 48 in a part of the rear end surface of the suction plate 22.

  Even if the hole H2 is formed, the strength of the suction plate 22 can be sufficiently secured. Moreover, the hole part H2 is corresponded to the part which concerns on distribution B1 and B2 in FIG. 4 similarly to the hole part H1. Therefore, the influence on the adsorption force due to the formation of the hole H2 is small enough to be ignored.

  As described above, according to the third embodiment, the weight of the reinforcing member 54 can be reduced while maintaining the effects of the first embodiment. As a result, the weight of the entire mold clamping device 10 can be further reduced.

  Note that the second embodiment and the third embodiment may be combined. That is, the hole H2 may be formed together with the hole H1 with respect to the reinforcing member 54. Even in this case, the reinforcing member 54 is disposed in a portion corresponding to the coil 48 in a part of the rear end surface of the suction plate 22. As a result, it is possible to appropriately ensure the strength of the suction plate 22 and maintain the suction force.

  Next, a fourth embodiment will be described. FIG. 8 is a diagram illustrating an arrangement example of the suction plate and the reinforcing member in the fourth embodiment.

  In the fourth embodiment, the reinforcing member 54 has not only the hole portion H1 and the hole portion H2 but also a concave portion or a hole portion in a portion corresponding to the vertical portion 48v of the coil 48. Therefore, the reinforcing member 54 can be formed as two square members. As a result, the reinforcing member 54 can be further reduced in weight as compared with the second or third embodiment.

  Even when the reinforcing member 54 is formed as shown in FIG. 8, the strength of the suction plate 22 can be sufficiently secured. That is, in FIG. 8, the reinforcing member 54 and the fixing member 53 are disposed on the rear end surface of the suction plate 22 in a lattice shape. By arranging the reinforcing member 54 and the fixing member 53 in a lattice shape, the strength (strength for preventing deflection) in all directions (vertical direction, horizontal direction, and other directions) with respect to the suction plate 22 is ensured. can do. Note that the fixing member 53 and the reinforcing member 54 do not necessarily have to be arranged at right angles. For example, the two fixing members 53 may be arranged in a square shape. That is, in the present embodiment, the “lattice shape” is not limited to a state in which the fixing member 53 and the reinforcing member 54 intersect at a right angle.

  Further, the reinforcing member 54 shown in FIG. 8 does not have a portion corresponding to the vertical portion 48v of the coil 48, but even the reinforcing member 54 having such a shape appropriately secures the suction force of the suction plate 22. be able to. That is, the vertical portion 48v is disposed not in the U-shaped groove having walls on both sides in the rear platen 13 but in a portion cut into an L shape with one side open. In other words, the portion of the vertical portion 48v opposite to the portion facing the core 48 does not face the magnetic body (rear platen 13). Furthermore, the vertical portion 48v is not sandwiched by the magnetic body in the direction facing the rear end surface of the rear platen 13. Therefore, air is interposed in the magnetic loop in the vertical portion 48v. As a result, the contribution to the attractive force is negligibly low. Therefore, the reinforcing member 54 does not necessarily have to be disposed in the portion corresponding to the vertical portion 48v. In view of securing the strength by the reinforcing member 54, the reinforcing member 22 does not necessarily have to be arranged in the vertical direction (vertical direction). This is because the reinforcing member 54 is for preventing the suction plate 22 from bending in the horizontal direction.

  The portion corresponding to the coil 48 may be a portion (region) having the same width as the coil 48 on the rear end surface of the suction plate 22, but may be a portion related to a width larger than the width of the coil 48. In FIG. 4, the width of the region A (the height of the region A in the drawing) is wider than the width of the coil 48 (the height of the coil 48 in the drawing). Therefore, an appropriate value may be calculated for the width of the reinforcing member 54 based on the analysis of the magnetic flux density distribution as shown in FIG. As a result, the widths of the two reinforcing members 54 may be different.

  As is clear from the fourth embodiment, the reinforcing member 54 does not necessarily have to be disposed in a portion corresponding to the entire coil 48. The replenishing member 54 may be disposed at a portion corresponding to at least a part of the coil 48. Therefore, in the present embodiment, “corresponding to the coil 48” includes a case corresponding to a part of the coil 48. When the reinforcing member 54 is disposed in a part corresponding to a part of the coil 48, the part is relatively relative to other parts in the reinforcing member 54 from the viewpoint of securing the suction force of the suction plate 22. It is preferable that the part has a high magnetic flux density. Further, from the viewpoint of securing the strength of the suction plate 22, the part is preferably a part related to the direction intersecting the fixing member 53 (part related to the horizontal direction in the present embodiment).

  Next, a fifth embodiment will be described. FIG. 9 is a diagram illustrating an arrangement example of the suction plate and the reinforcing member in the fifth embodiment. 9, parts that are the same as the parts shown in FIG. 8 are given the same reference numerals, and explanation thereof is omitted as appropriate.

  In the fifth embodiment, the side on the rear end side in the cross section of the reinforcing member 54 is formed as a curve such as an arc or an elliptic arc. As a result, the cross section of the reinforcing member 54 has a so-called bowl shape. This is a result of approximating the cross section of the reinforcing member 54 to the shape of the distribution B3 in the region A of FIG. By approximating the cross section of the reinforcing member 54 to the shape of the distribution B3 in the region A, the contribution of the reinforcing member 54 to the suction force can be made more efficient.

  As described above, the reinforcing member 54 is not necessarily a square member. Further, although not shown, the fixing member 53 is not limited to a square member. When not a square member, the cross section of the fixing member 53 may be the same shape as the cross section of the reinforcing member 54 or a different shape.

  Next, a sixth embodiment will be described. FIG. 10 is a diagram illustrating an arrangement example of the suction plate and the reinforcing member in the sixth embodiment.

  In the sixth embodiment, the rear platen 13 has a coil 48a or a coil 48b (hereinafter collectively referred to as “coil 48”) wound around each of two cores 46a and 46b arranged in the vertical direction. ing. As a result, two electromagnets are formed. From the viewpoint of the balance of the attractive force, it is desirable that the positions of the core 46a and the core 46b are arranged symmetrically with respect to a virtual straight line that bisects the rear platen 13 in the horizontal direction.

  Even when the two coils 48 are wound around the rear platen 13, the position where the reinforcing member 54 is disposed may be basically as described in the above embodiment. That is, a part of the rear end face of the suction plate 22 includes a part corresponding to the coil 48. Further, in the example of the figure, the reinforcing member 54 is not disposed in a portion corresponding to the vertical portion of the coil 48. Even in this case, the suction force in the suction plate 22 can be appropriately secured as described in the fourth embodiment.

  FIG. 11 is a diagram illustrating an arrangement example of the suction plate and the reinforcing member in the seventh embodiment.

  In the figure, four reinforcing members 54 are arranged on the rear end surface of the suction plate 22 so as to correspond to the horizontal portion of the coil 48. As a result, the reinforcing member 54 and the fixing member 53 are arranged on the rear end surface of the suction plate 22 in a lattice shape, as in the fourth embodiment. Therefore, the total weight of the reinforcing member 54 can be reduced as compared with the sixth embodiment. However, the strength and suction force of the suction plate 22 can be appropriately secured as described in the fourth embodiment.

  Next, an eighth embodiment will be described. FIG. 12 is a diagram illustrating an arrangement example of the suction plate and the reinforcing member in the eighth embodiment.

  In the figure, the rear platen 13 has four cores 46 (46a, 46b, 46c, and 46d) equally in the horizontal direction and the vertical direction. Coils 48 a, 48 b, 48 c, or 48 d (hereinafter collectively referred to as “coil 48”) are wound around each core 46. As a result, four electromagnets are formed.

  Even when the four coils 48 are wound around the rear platen 13, the position where the reinforcing member 54 is disposed may be basically as described in the above embodiment. That is, a part of the rear end face of the suction plate 22 includes a part corresponding to the coil 48. In the example of the figure, an example is shown in which all the grid-like members of the grid disposed on the rear end surface of the suction plate 22 are disposed as the reinforcing member 54. That is, in this example, the reinforcing member 54 also serves as the fixing member 53. Therefore, the lower end surface of the reinforcing member 54 is fixed to the slide base Sb. Further, in the figure, the reinforcing member 54 is disposed in a portion corresponding to the entire coil 48.

  In the reinforcing member 54, a portion extending in the vertical direction (vertical portion) is a portion that also serves as the fixing member 53. However, the role of the reinforcing member 54 is so small that the two outer vertical portions 54v1 and 54v4 are negligible. This is because the vertical portions 54v1 and 54v4 correspond to portions of the coil 48 that are not sandwiched between magnetic bodies. On the other hand, the inner two vertical portions 54v2 and 54v3 correspond to portions sandwiched between the magnetic bodies in the coil 48 (that is, portions disposed in the grooves formed in the rear platen 13). Accordingly, the vertical portions 54v2 and 54v3 function as the reinforcing member 54 in the role of reinforcing the attractive force.

  Further, the portion (horizontal portion) extending in the horizontal direction in the reinforcing member 54 is a portion that functions as the reinforcing member 54. That is, the strength against the horizontal deflection of the suction plate 22 can be reinforced by the horizontal portion. However, from the viewpoint of reinforcing the adsorption force, the role of the outer horizontal portions 54h1 and 54h4 as the reinforcing member 54 is so small that it can be ignored. This is because the vertical portions 54h1 and 54h4 correspond to portions of the coil 48 that are not sandwiched between magnetic bodies. On the other hand, the two inner horizontal portions 54h2 and 54h3 correspond to the portions sandwiched between the magnetic bodies in the coil 48 (that is, the portions disposed in the grooves formed in the rear platen 13). Accordingly, the vertical portions 54h2 and 54h3 function as the reinforcing member 54 in the role of reinforcing the attractive force.

  Next, a ninth embodiment will be described. FIG. 13 is a diagram illustrating an arrangement example of the suction plate and the reinforcing member in the ninth embodiment. In FIG. 13, the same parts as those in FIG.

  The reinforcing member 54 in the figure is a modification of FIG. That is, weight reduction is achieved by removing a portion that does not contribute to the attractive force in FIG. 12 (a portion that is so small that the contribution to the attractive force can be ignored). In FIG. 12, the portions that do not contribute to the suction force are the vertical portions 54v1 and 54v4 and the horizontal portions 54h1 and 54h4. However, a part of the horizontal portion 54h4 (a portion having a predetermined width (predetermined height) from the surface fixed to the slide base Sb) serves as the fixing member 53 fixed to the slide base Sb. Therefore, all of the horizontal portion 54h4 or a part of the lower end side remains.

  Also with the reinforcing member 54 shown in the ninth embodiment, the strength and suction force of the suction plate 22 can be appropriately reinforced.

  Next, a tenth embodiment will be described. FIG. 14 is a diagram illustrating an arrangement example of the suction plate and the reinforcing member in the tenth embodiment.

  The rear platen 13 of the tenth embodiment is different from the eighth and ninth embodiments in the shape of the core 46. In other words, each of the cores 46a, 46b, 46c, and 46d has a pentagonal cross section. Therefore, each core 46 has a pentagonal shape. The shape of the coil 48 wound around the core 46 having such a shape also corresponds to the shape of the core 46. That is, each coil 48 has an inclined portion as well as a vertical portion and a horizontal portion.

  Therefore, the reinforcing member 54 in FIG. 14 is deformed according to the deformation of the coil 46. Specifically, the reinforcing member 54 is disposed not only on the vertical portion and the horizontal portion of the coil 48 but also on the portion corresponding to the inclined portion of the coil 48 on the rear end surface of the suction plate 22. Therefore, in the tenth embodiment, it can be said that the reinforcing member 54 is disposed in a portion corresponding to the coil 48 in a part of the rear end surface of the suction plate 22. In the tenth embodiment, as in the ninth embodiment, the reinforcing member 54 is not disposed in a portion corresponding to a portion of the coil 48 that is not sandwiched between magnetic bodies. However, it is not intended to exclude the form in which the reinforcing member 54 is disposed in the portion.

  Note that the shape of the coil 48 is not limited to that shown in the above embodiments. For example, a part of the coil 48 may protrude from the side surface of the rear platen 13 in the lateral direction. That is, the coil 48 may not be completely contained in the rear platen 13.

  Further, the coil 48 may be disposed such that a portion extending in the vertical direction is longer than a portion extending in the horizontal direction (that is, in a shape extending in the vertical direction).

  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.

10 mold clamping device 11 fixed platen 12 movable platen 13 rear platen 13a leg 14 tie bar 15 fixed mold 16 movable mold 17 injection device 18 injection nozzle 19 mold device 22 suction plate 28 linear motor 29 stator 31 mover 33 magnetic pole teeth 34 Core 35 Coil 37 Electromagnet unit 39 Rod 41, 42 Hole 46 Core 47 Yoke 48 Coil 49 Electromagnet 51 Adsorption part 53 Fixing member 54 Reinforcement member 81, 82 Space Fr Frame Gd Guide Gb Guide base Sb Slide base

Claims (5)

A mold clamping device that performs a clamping operation using an electromagnet,
A coil holding member having a coil holding surface for holding a coil of the electromagnet;
An adsorption member facing the coil holding surface and having an adsorption surface adsorbed by the electromagnet;
A magnetic reinforcing member that reinforces the attracting member;
The said clamping member is a mold clamping apparatus arrange | positioned so that the part corresponding to at least one part of the said coil may be included in a part of back surface with respect to the said adsorption surface in the said adsorption member.   The mold clamping device according to claim 1, wherein a portion corresponding to at least a part of the coil is a portion having a relatively high magnetic flux density in a portion corresponding to the coil on the back surface.   The mold clamping device according to claim 1, wherein the reinforcing member and the adsorption member are integrally formed. A slide member fixed to the mold opening / closing drive unit and moving in the mold opening / closing direction by driving of the mold opening / closing drive unit;
A fixing member that fixes the suction member to the slide member by being fixed to the suction member at a portion that is fixed to the horizontal surface of the slide member and extends in a vertical direction on the back surface of the suction member; Have
The mold clamping device according to any one of claims 1 to 3, wherein the reinforcing member and the fixing member are integrally formed.   The mold clamping device according to claim 4, wherein the reinforcing member and the fixing member are arranged in a lattice shape on the back surface.

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