Mold clamping device and injection molding machine

Abstract

To propose a mold clamping device that prevents the rotating plate from deflecting in the collapsing direction.SOLUTION: The mold clamping device (2) is composed of a stationary board (5) fixed to the bed (B), a movable board (7) that can slide freely against the bed (B), a rotating board (4) on the movable board (7), and a rotating board support (13) that rotatably supports the rotating board (4). A rail (24) is laid on the bed (B), and the turntable support (13) is provided with turntable side sliders (27, 28) that slide guided by the rail (24).SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a mold clamping device in which a rotary platen is provided on a movable platen, and an injection molding machine. [Background technology]

[0002] The mold clamping device provided in an injection molding machine includes a fixed platen and a movable platen that opens and closes relative to the fixed platen. Some injection molding machines have a rotating platen attached to the movable platen, as shown in Patent Document 1, for example. In such an injection molding machine, a plurality of rotating molds are provided on the rotating platen, and the rotational position of the rotating platen is changed each time the mold is opened or closed to clamp the molds. In this way, the rotating mold that is clamped relative to the fixed mold provided on the fixed platen is replaced. Molded products can be efficiently molded by replacing the plurality of rotating molds. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2009-45939 Summary of the Invention [Problem to be solved by the invention]

[0004] The movable platen is slidably mounted on the bed and slides horizontally toward the fixed platen. The rotating platen is rotatably mounted on the surface of the movable platen facing the fixed platen. As a result, a moment acts on the movable platen and rotating platen in a direction that causes them to tip toward the fixed platen due to the weight of the rotating platen. Furthermore, since a mold is mounted on the rotating platen, this moment also acts due to the weight of the mold. The movable platen is guided, for example, by tie bars or other guide mechanisms to prevent tipping. However, the rotating platen is only supported rotatably relative to the rotating platen. As a result, the action of these moments causes the rotating platen to bend in the direction of tipping. This causes a problem that affects the mold clamping accuracy when the mold is clamped.

[0005] The present disclosure proposes a mold clamping device that prevents the turntable from bending in the tilt direction.

[0006] Other objects and novel features will become apparent from the description of this specification and the accompanying drawings. [Means for solving the problem]

[0007] In the present disclosure, a mold clamping device is configured from a fixed platen fixed to a bed, a movable platen provided so as to be slidable relative to the bed, a rotating platen provided on the movable platen, and a rotating platen support member that rotatably supports the rotating platen. The movable platen has a slider that slides along the rail, and The turntable support has a turntable side slider that slides along the rail. each establish. [Effects of the Invention]

[0008] According to the present disclosure, deflection of the turntable in the tilting direction can be prevented. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a side view of an injection molding machine according to an embodiment of the present invention. [Figure 2] FIG. 2 is a front view showing a rotary table and a part of a mold clamping device according to the present embodiment. [Figure 3] FIG. 2 is a perspective view showing, in partial cross section, a cross roller bearing provided between the fixed platen and the rotating platen. [Figure 4] FIG. 2 is a side view showing a part of the mold clamping device according to the present embodiment. [Figure 5A] FIG. 2 is a side view showing a part of a mold clamping device according to a first modified example of the present embodiment. [Figure 5B] FIG. 10 is a side view showing a part of a mold clamping device according to a second modified example of the present embodiment. [Figure 6A] FIG. 10 is a front view showing a part of a rotary table and a mold clamping device according to a third modified example of the present embodiment. [Figure 6B] FIG. 10 is a side view showing a part of a rotary table and a mold clamping device according to a third modified example of the present embodiment. [Figure 6C] FIG. 10 is a front view showing a part of a rotary table and a mold clamping device according to a fourth modified example of the present embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] Specific embodiments will be described in detail below with reference to the drawings. However, the present invention is not limited to the following embodiments. For clarity of explanation, the following description and drawings have been simplified as appropriate. In each drawing, the same elements are given the same reference numerals, and duplicate explanations are omitted as necessary. Furthermore, hatching has been omitted in some areas to avoid cluttering the drawings.

[0011] The present embodiment will be described. <Injection molding machine> As shown in FIG. 1, the injection molding machine 1 according to this embodiment is generally composed of a mold clamping device 2 that clamps a mold, and an injection device 3 that melts and injects an injection material.

[0012] <Mold clamping device> The mold clamping unit 2 includes a fixed platen 5 fixed on bed B, a mold clamping housing 6 that slides on bed B, a movable platen 7 that similarly slides on bed B, and a rotating platen 4, which will be described next. The fixed platen 5 and the mold clamping housing 6 are connected by a plurality of tie bars 9, for example, four tie bars 9. The movable platen 7 is slidable between the fixed platen 5 and the mold clamping housing 6. A mold clamping mechanism 11 is provided between the mold clamping housing 6 and the movable platen 7. The mold clamping mechanism 11 may be a direct pressure type mold clamping mechanism, that is, may be configured from a mold clamping cylinder, but in this embodiment it is configured from a toggle mechanism.

[0013] <Turntable> The mold clamping unit 2 according to this embodiment is provided with a turntable support 13, and the turntable 4 according to this embodiment is supported by this turntable support 13. In other words, the turntable 4 is provided rotatably with respect to the movable platen 7, and is supported by the turntable support 13. As shown in FIG. 2, the turntable support 13 is provided with two rollers 15, 15, and the outer circumferential surface of the turntable 4 is placed on these rollers 15, 15. The turntable support 13 is supported by the bed B via a guide mechanism, as will be described in detail later. Therefore, the weight of the turntable 4 acts on the bed B via the turntable support 13.

[0014] The rotating platen 4 has been described as being rotatably mounted relative to the movable platen 7, and a cross roller bearing 45 shown in FIG. 3 is provided between the movable platen 7 and the rotating platen 4. The cross roller bearing 45 is composed of an outer ring 46 disposed on the outside, a pair of inner rings 47, 47 disposed on the inside, and a number of rollers 49, 49, ... disposed between them. The outer ring 46 and the inner rings 47, 47 rotate smoothly relative to each other. The rotating platen 4 (see FIG. 1) is connected to the movable platen 7 by such a cross roller bearing 45, so the rotating platen 4 rotates smoothly.

[0015] As shown in Figure 1, a drive motor 16 is provided on the top of the movable platen 7, and a pulley 18 is provided on the drive motor 16. A belt 19 is wound around this pulley 18 and the turntable 4. Therefore, when the drive motor 16 is driven, the turntable 4 rotates.

[0016] In the mold clamping device 2 configured as above, as shown in Figures 1 and 2, a fixed-side mold 21 is attached to the fixed platen 5, and two rotating-side molds 22, 22 are provided on the rotating platen 4. One of the two rotating-side molds 22, 22 is aligned with the fixed-side mold 21 depending on the rotational position of the rotating platen 4. When the mold clamping mechanism 11 is driven, the fixed-side mold 21 and the aligned rotating-side mold 22 are opened and closed.

[0017] <Guide mechanism> The mold clamping unit 2 according to this embodiment is characterized in that it is provided with a guide mechanism. This will be explained. As shown in FIGS. 1 and 2, the guide mechanism is composed of two rails 24, 24 laid on the bed B, and multiple sets of sliders 25, 26, 27, 28 slidably provided on the rails 24, 24. First, the mold clamping housing 6 is provided with a set of mold clamping housing side sliders 25. And the movable platen 7 is also provided with a set of movable platen side sliders 26. Therefore, the mold clamping housing 6 and the movable platen 7 are configured to slide smoothly on the rails 24, 24.

[0018] The turntable support 13 is also provided with sliders 27, 28, but two sets of sliders are provided on the turntable support 13: first and second turntable sliders 27, 28. The turntable support 13, as partially shown in FIG. 1, has a protrusion 30 that protrudes toward the rotating mold 22. When viewed from a horizontal direction perpendicular to the rails 24, 24, i.e., when viewed from the direction shown in FIG. 1, the first turntable slider 27 is located below the center of gravity of the turntable 4. In contrast, the second turntable slider 28 is provided on the protrusion 30. More specifically, the second turntable slider 28 is located closer to the fixed platen 5 than the mold mounting surface 32 of the turntable 4. Therefore, the second turntable slider 28 is located below the center of gravity of the rotating molds 22, 22.

[0019] <Injection device> The injection device 3 is composed of a heating cylinder 35, a screw 36 placed in the heating cylinder 35, and a screw drive device 38 that drives the screw 36. The heating cylinder 35 has a hopper 40 near its rear end and an injection nozzle 41 at its tip.

[0020] <effect> The operation of the mold clamping unit 2 according to this embodiment will be described. Consider the case where the mold clamping unit 2 is in the mold open state as shown in FIG. 4. The weight of the movable platen 7 acts on the movable platen slider 26 as indicated by arrow 51, and the weight of the turntable 4 acts on the first turntable slider 27 as indicated by arrow 52 via the turntable support 13, thereby supporting the movable platen 7 and the turntable 4. The weight of the turntable mold 22 acts indirectly on the second turntable slider 28 as indicated by dotted arrow 53, thereby being supported. As a result, the weights of the turntable 4 and the turntable mold 22 do not act on the movable platen 7, or act only to a small extent. Therefore, no deflection occurs in the tilt direction of the turntable 4 relative to the movable platen 7. As a result, the turntable mold 22 and the fixed mold 21 are aligned with high precision, and the mold is clamped with high precision when the mold clamping unit 2 is driven to clamp the molds.

[0021] Now, consider the case where the turntable support 13 is not present. Without the turntable support 13, a moment indicated by arrow 55 acts on the turntable 4 due to the weight of the turntable 4 and the rotating mold 22. This moment causes the turntable 4 to bend in a tilting direction relative to the movable platen 7. This causes the rotating mold 22 to tilt slightly, reducing its alignment with the fixed mold 21. Sufficient precision cannot be obtained when driving the clamping unit 2 to clamp the mold. In contrast, the clamping unit 2 according to this embodiment is equipped with a turntable support 13, which is slidable relative to the bed B via a guide mechanism. Therefore, the moment indicated by arrow 55 is hardly generated, and the above-mentioned effect can be obtained.

[0022] <Variation 1> Modification 1 of the mold clamping apparatus 2 according to the present embodiment will be described. FIG. 5A shows a mold clamping apparatus 2A according to Modification 1. However, regarding the configuration of the mold clamping apparatus 2A, parts not shown in FIG. 5A are the same as those of the mold clamping apparatus 2 shown in FIGS. 1 and 2, and therefore their description will be omitted. In the mold clamping apparatus 2A according to Modification 1, the lower part of the turntable support 13A does not protrude toward the rotating-side mold 22. In other words, there is no protrusion 30 as shown in FIG. 4. Although there is no protrusion 30, as shown in FIG. 5A, the turntable support 13A is supported on the rail 24 by the turntable-side slider 27A. Therefore, in the mold clamping apparatus 2A according to Modification 1, the weight of the turntable 4 hardly acts on the movable platen 7. Or, if it does act, it is only slight. In other words, in the mold clamping apparatus 2A according to Modification 1, deflection in the tilting direction of the turntable 4 is unlikely to occur.

[0023] <Variation 2> Modification 2 of the mold clamping device 2 according to this embodiment will be described. FIG. 5B shows a mold clamping device 2B according to Modification 2. However, the configuration of the mold clamping device 2B not shown in FIG. 5B is the same as that of the mold clamping device 2 shown in FIGS. 1 and 2, and therefore, description thereof will be omitted. In the mold clamping device 2B according to Modification 2, a protrusion 30B is formed on the turntable support 13B. However, the degree of protrusion is relatively small compared to the first embodiment shown in FIG. 3. The turntable side slider 27B provided on the turntable support 13B is not positioned so as to protrude from the mold mounting surface 32 toward the rotation-side mold 22. In other words, in the mold clamping device 2B according to Modification 2, the turntable side slider 27B is provided at a position intermediate between the turntable 4 and the rotation-side mold 22. It can also be said that the turntable side slider 27B is positioned at the combined center of gravity of the turntable 4 and the rotation-side mold 22. In this embodiment as well, deflection of the turntable 4 in the tilting direction is unlikely to occur.

[0024] <Variation 3> Modification 3 of the mold clamping device 2 according to the present embodiment will be described. FIGS. 6A and 6B show a mold clamping device 2C according to Modification 3. However, with regard to the configuration of the mold clamping device 2C, parts not shown in FIGS. 6A and 6B are the same as those of the mold clamping device 2 shown in FIGS. 1 and 2, and therefore their description will be omitted. In the mold clamping device 2C according to Modification 3, as shown in FIG. 6A, an annular portion 60 that supports the turntable 4 on its inner circumferential surface is formed on the turntable support 13C. In other words, the turntable 4 rotates while contacting the inner circumferential surface of the annular portion 60. However, most of the weight of the turntable 4 acts on the lower portion of the inner circumferential surface of the annular portion 60.

[0025] A hole 64 is formed in the annular portion 60 from the back side as viewed in FIG. 6A, and a roller 65 is inserted into this hole 64 from the back side. As shown in FIG. 6B, a motor 62 is provided on the movable platen 7, and the roller 65 is rotated by the motor 62. Rubber is provided on the outer circumferential surface of the roller 65, and it is in contact with the outer circumferential surface of the turntable 4. Therefore, when the motor 62 is driven, the roller 65 rotates, and the turntable 4 can be rotated. In this modification 3 as well, the weight of the turntable 4 is supported by the turntable support 13C, and the turntable support 13C is supported by the second turntable-side slider 28.

[0026] <Variation 4> Modified example 4 of the mold clamping apparatus 2 according to the present embodiment will be described. Fig. 6C shows a mold clamping apparatus 2D according to modified example 4. However, parts of the configuration of the mold clamping apparatus 2D that are not shown in Fig. 6C are the same as those of the mold clamping apparatus 2 shown in Figs. 1 and 2, and therefore their description will be omitted. In the mold clamping apparatus 2D according to modified example 4, a plain bearing structure 68 that supports the turntable 4 below is provided on the turntable support 13D. The plain bearing structure 62 is configured to slidably support the outer peripheral surface of the turntable 4. Although only one plain bearing structure 68 is provided in the mold clamping apparatus 2D according to modified example 4, two or more may be provided.

[0027] The mold clamping device 2D according to the modified example 4 is also characterized in that it is provided with four rails 24, 24, .... In relation to these rails 24, 24, ..., four second turntable side sliders 28, 28, ... are also provided on the turntable support body 13D. As can be easily understood from the mold clamping device 2D according to the modified example 4, the mold clamping device 2 according to this embodiment (see Figs. 1 and 2) is also not limited in the number of rails 24, 24, ... and the number of sliders 25, 26, ..., and can be freely modified.

[0028] The invention made by the inventor has been specifically described above based on the embodiments, but it goes without saying that the present invention is not limited to the above-described embodiments and various modifications are possible without departing from the spirit of the invention. The multiple examples described above can also be implemented in appropriate combinations. [Explanation of symbols]

[0029] 1 Injection molding machine 2 Mold clamping device 3 Injection unit 4 Turntable 5 Stationary platen 6 Clamping housing 7 Movable platen 9 Tie bar 11 mold clamping mechanism 13 turntable support 15 Roller 16 Drive motor 18 Pulley 19 Belt 21 Fixed side mold 22 Rotating side mold 24 Rail 25 Mold clamping housing side slider 26 Movable platen side slider 27 First rotating platen side slider 28 second turntable side slider 30 protrusion 32 mold mounting surface 35 heating cylinder 36 Screw 38 Screw drive device 40 Hopper 41 Injection nozzle 45 Cross roller bearing 46 Outer ring 47 Inner ring 49 Roller 60 annular portion 62 motor 65 Roller 68 Slide bearing structure

Claims

1. a fixed platen fixed to the bed so that a fixed mold can be provided; a movable platen that is slidably provided relative to the bed; A rotating platen on which a rotating mold is provided; a turntable support that rotatably supports the turntable, the rotary platen is rotatably provided relative to the movable platen, The bed is provided with rails, The mold clamping device is provided with a movable platen side slider that slides while being guided by the rail on the movable platen, and a rotary platen side slider that slides while being guided by the rail on the rotary platen support body.

2. The mold clamping device according to claim 1 , wherein the number of the turntable side sliders is two or more.

3. The mold clamping device described in claim 2, wherein the slider mounting portion on which the turntable side slider of the turntable support is provided is a protruding portion that protrudes toward the fixed platen from the mold mounting surface of the turntable, and at least one set of the turntable side sliders is arranged on the protruding portion.

4. 3. The mold clamping device according to claim 1, wherein the rotary platen is rotatably mounted on the movable platen via a cross roller bearing.

5. a mold clamping device that clamps the mold; an injection device that melts an injection material and injects it into the mold; The mold clamping device includes a fixed platen fixed to a bed and configured to have a fixed mold thereon; a movable platen that is slidably provided relative to the bed; A rotating platen on which a rotating mold is provided; a turntable support that rotatably supports the turntable, the rotary platen is rotatably provided relative to the movable platen, The bed is provided with rails, an injection molding machine, wherein the movable platen is provided with a movable platen-side slider that slides while being guided by the rail, and the rotary platen support body is provided with a rotary platen-side slider that slides while being guided by the rail.

6. 6. The injection molding machine according to claim 5, wherein the number of the turntable-side sliders is two or more.

7. 7. The injection molding machine according to claim 6, wherein a slider mounting portion of the turntable support on which the turntable side sliders are provided is a protruding portion that protrudes toward the fixed platen from the mold mounting surface of the turntable, and at least one set of the turntable side sliders is disposed on the protruding portion.

8. 7. The injection molding machine according to claim 5, wherein the rotary platen is rotatably mounted on the movable platen via a cross roller bearing.

Images