JP5805604B2 - Injection molding equipment - Google Patents

Description

  The present invention relates to an injection molding machine including one mold clamping unit and two injection units.

  An injection molding machine or an injection molding method is well known in the art without mentioning a literature name. In general, an injection molding machine includes a mold clamping unit and an injection unit. The mold clamping unit includes a fixed plate fixed to the bed, a fixed mold attached to the fixed plate, a movable plate paired with the fixed plate, a movable mold attached to the movable plate, and the like. On the other hand, the injection unit includes a heating cylinder, a screw that can be driven in the rotation direction and the axial direction in the heating cylinder, and a hydraulic or electric motor that drives the screw. The injection unit is provided on the bed so as to be movable in the axial direction. A standard injection molding machine including such a mold clamping unit and an injection unit is provided with one injection unit corresponding to the mold clamping unit. Accordingly, the screw of the injection unit can be rotationally driven to plasticize the molding material and be measured in the accumulation chamber in front of the heating cylinder. Then, the molten molding material measured by driving the screw in the axial direction is injected into the mold cavity of the mold clamping unit, and after waiting for cooling and solidification, the movable platen is opened to obtain a molded product.

  By the way, recently, there are many molded products using composite materials to increase added value, for example, molded products formed by a sandwich molding method, molded products made of different materials such as hard and soft materials, or different color materials. It is supposed to be. In a molded product made of these composite materials, two injection units are applied to one mold clamping unit. An example of the molding apparatus will be briefly described in Patent Documents 1 and 2.

JP-A-9-76296 JP 2000-210979 A

  The sandwich molding method is a method in which the material of the resin constituting the surface layer and the inner layer, that is, the skin layer and the core layer of the molded product is changed and injection molding is performed at the same time. The injection molding machine applied to sandwich molding in this way is patented It is described in Document 1. That is, an apparatus including the first and second two injection units, one nozzle structure, and one mold clamping unit is shown. A first injection unit is connected to the resin passage formed at the center of the nozzle structure, and a second injection unit is connected to the resin passage formed at the periphery of the nozzle structure. The resin passages merge at the injection nozzle hole on the downstream side. Therefore, a sandwich molded product can be obtained by simultaneously injecting resins having different properties from the first and second injection units.

  The core back method is known as one of the molding methods for complex molded products, for example, molded products made of different materials or different color materials such as hard and soft materials. The core back method consists of primary molding and secondary molding. At the time of primary molding, a part of the cavities is sealed with a moving core, and molten resin is injected and filled into the vacant cavities. A method of forming a molded product, retracting the moving core during secondary molding, and injecting molten resin into the retracted space to obtain a molded product integrated with the primary semi-molded product. A molded product of the material can be obtained. The injection molding machine applied to the implementation of this method is also composed of first and second two-head injection units and one mold clamping unit, as shown in Patent Document 2, for example. Further, in Patent Document 2, a standard injection molding machine including one mold clamping unit and one injection unit is provided at the center of the injection bed as a conventional example for improving the core back molding machine. It is also shown that the existing injection unit is moved to place the second injection unit.

  As described above, an injection molding machine having two injection units is known from the above-mentioned patent literature, and therefore, using such an injection molding machine, molded products of different colors or different materials are used. Can be formed alternately. For example, when the first injection unit is used to inject a red first resin to obtain a predetermined number of molded products, and then the second injection unit is used to inject a black second resin, one unit Two molds having different colors or different materials can be alternately molded by the mold clamping unit. However, the replacement work of the injection material takes time, and there is a problem in implementation. That is, for example, when the second injection unit is at rest, the injection material deteriorates during that time, so the inside of the unit must be purged prior to injection, but the conventional injection molding machine having two injection units However, there is a problem that purging or material change takes time and molding cannot be performed efficiently because no special measures are taken to purge the dormant injection unit.

  Therefore, the present invention comprises two injection units for one mold clamping unit, and when these injection units are selectively used and molded alternately, the rest of the injection units are set in advance or whenever necessary. An object of the present invention is to provide an injection molding machine capable of preparing for the next molding such as purging, maintenance and inspection.

In the present invention, in order to achieve the above object, two first and second injection units are applied to one mold clamping unit. However, when these injection units are separated, they are independent of each other. Are mounted on a single movable gantry composed of first and second slide cradles that can be driven . When the movable base is moved and the first injection unit moves to a molding position aligned with the mold clamping unit, the second injection unit takes a retracted position away from the mold clamping unit, and the second injection unit When moved to a molding position aligned with the mold clamping unit, the first injection unit is configured to take a retracted position separated from the mold clamping unit.

That is, in order to achieve the object, the invention according to claim 1 is a stationary platen to which a fixed mold is attached, a movable plate to which a movable mold is attached, and the movable plate to the fixed plate. One mold clamping unit consisting of a mold clamping device that opens and closes, a heating cylinder having an injection nozzle at the tip, and a screw provided in the heating cylinder so as to be able to be driven in the rotational direction and the axial direction. Comprising two first and second injection units comprising a driving device and the like, and a single movable gantry comprising first and second slide gantry that can be independently driven when separated . With respect to the one mold clamping unit, the two first and second injection units are respectively mounted on the first and second slide mounts of the one moving mount, whereby the moving mount is To the first molding position When moved, the first injection unit takes a molding position aligned with the mold clamping unit, the second injection unit takes a retracted position away from the mold clamping unit, and the movable base is a second one. When driven to the molding position, the second injection unit takes a molding position aligned with the mold clamping unit, and the first injection unit takes a retracted position spaced from the mold clamping unit. The

According to a second aspect of the present invention, in the injection molding apparatus according to the first aspect of the present invention, one moving gantry comprising the first and second slide gantry slides laterally with respect to the clamping unit by a ball screw mechanism. Driven by the first and second molding positions, and the invention according to claim 3 is the injection molding apparatus according to claim 1, wherein the first and second slide mounts are ball screw mechanisms. Are configured to be driven independently of each other.

As described above, according to the present invention, when the first and second injection units are separated, they are mounted on one movable gantry comprising the first and second slide cradles that can be driven independently. Is driven to the first molding position, the first injection unit adopts a molding position aligned with the mold clamping unit. Therefore, a molded product is formed with a predetermined resin by the first injection unit and the mold clamping unit. Can be molded. When molding in this way, the second injection unit takes a retracted position away from the mold clamping unit, so that the second injection unit can be purged, replaced with resin, and the like. Alternatively, maintenance and inspection can be performed. Conversely, when the movable platform is driven to the second molding position and molded by the second injection unit, the first injection unit takes a retracted position away from the mold clamping unit. The first injection unit can be purged or the resin can be replaced. As described above, according to the present invention, only by moving the movable base, when molding is performed by one injection unit of the first and second injection units, the other injection unit is purged or the resin is replaced. Therefore, it is possible to obtain an effect that different resins or molded products of different colors can be molded efficiently without alternately stopping. In addition, since the movable mount can be separated into the first and second slide mounts, a large and heavy movable mount can be divided, manufactured, transported, and assembled on site. Furthermore, when the movable frame is separated into the first and second slide tables, each slide frame can be driven independently, so the first and second injection units can be retracted independently. The effect of being able to drive to the position and perform individual maintenance inspection is further obtained.

According to the second or third aspect of the invention, since the movable frame or the slide frame is driven by the ball screw mechanism, it is driven to the first and second molding positions at a high speed and stopped with high accuracy. The effect that can be further obtained.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows typically the injection molding apparatus which concerns on the 1st Embodiment of this invention, The (a) is a top view, The (a) is a side view. BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows typically the ball screw mechanism of the injection molding apparatus which concerns on the 1st Embodiment of this invention, The (a) is the state by which the movable mount was driven to the 1st molding position, The (a) is It is a top view shown in the state driven to the 2nd forming position, respectively. It is a figure which shows typically the injection molding apparatus which concerns on the 2nd Embodiment of this invention, The (a) is a top view, The (b) is a back view of a movable mount frame.

  Embodiments of the present invention will be described below. As shown in FIG. 1, the injection molding apparatus according to the first embodiment includes one mold clamping unit 1 and one injection apparatus 10. The injection device 10 includes two first and second injection units 11 and 11 '. The first and second injection units 11 and 11 ′ are mounted on the movable base 20, and are parallel to the mold clamping unit 1 in the horizontal direction and slide in the vertical direction in the plan view of FIG. Driven.

  Since the mold clamping unit 1 is well known in the art, only a part of the components are shown, but the mold is opened and closed with respect to the fixed platen 2 and the fixed platen 2 fixedly provided on the injection table. The movable platen 3 includes a fixed mold 4 attached to the fixed platen 2, a movable mold 5 attached to the movable platen 3, and the like. A cavity 6 for forming a molded product is formed on the mold-matching surface of the solid side mold 4 and the movable side mold 5, and a spru 7 formed in the fixed side mold 4 is opened in the cavity 6. ing.

  The two first and second injection units 11 and 11 ′ can be constructed structurally or from units different in size, but in the embodiment shown in FIG. Since the structure is the same in terms of size, the first injection unit 11 will be described, and the second injection unit 11 ′ will be duplicated by adding a dash “′” to the same reference numeral in the drawings. I do not. The first injection unit 11 is a conventionally known standard unit in the present embodiment shown in FIG. 1, and is composed of a heating cylinder 12 having a predetermined length in the axial direction. Inside the heating cylinder 12, a screw is provided so as to be driven in the rotational direction and the axial direction, and an injection nozzle 13 is provided at the tip. The injection nozzle 13 is provided with a purge cover for preventing the purge resin from scattering. The purge cover, for example, as shown in Japanese Utility Model Laid-Open No. 60-187015, has a position covering the injection nozzle 13 and a position retracted from this position. This type of purge cover is not shown. Near the rear of the heating cylinder 12, a hopper 15 for supplying resin pellets, which is an injection material, is attached. A screw driving device 16 is provided at the rear end. The heating cylinder 12 and the like configured as described above are attached to the injection table 17 so as to be driven in the axial direction, that is, movable in the nozzle touch direction or the separation direction approaching the mold clamping unit 1. Thus, the first injection unit 11 having a conventionally known form is configured. This injection stand 17 is fixedly attached to a movable stand 20 described later.

The moving platform 20 according to the first embodiment, consists of the first and second slide frame 21, 21 'as shown in FIGS. 1 and 2, one coupled as described they then It is a mobile stand . These slide bases 21 and 21 ′ have a substantially square shape, and flanges 22 and 22 ′ that also serve as reinforcements that rise by a predetermined amount are formed on the abutting end surfaces. These flanges 22 and 22 'are fastened by bolts and nuts 23, 23, ... for fastening, and are separably coupled.

  Linear guide rails 25, 25 that support the movable frame 20 from the lower surface and smoothly guide the mold clamping unit 1 in a direction perpendicular to or transverse to the mold clamping unit 1 are provided over a predetermined length at predetermined intervals. Although a hydraulic piston / cylinder unit, a gear mechanism, and the like can be applied to the device that drives the movable gantry 20, a ball screw mechanism is applied in the present embodiment. As shown in FIG. 2, the ball screw mechanism includes a bearing 27 ′ that also receives a thrust load, a first ball screw 31 having a predetermined pitch that is rotatably supported by the bearing 27, 27, and a bearing 27 ′ that also receives a thrust load. The second ball screw 31 'is rotatably supported by the shaft 27'. The bearings 27, 27 ′ are attached to a frame 25 ′ extending in parallel with the linear guide rails 25, 25, as partly shown in FIG. Therefore, the first and second ball screws 31, 31 'are in series. Note that the pitch of the first ball screws 31 is larger than that of the second ball screws 31 '. Thereby, when the moving mount 20 is driven, the first ball screw 31 rotates smoothly following.

  An electric servo motor 33 is attached to the end of the second ball screw 31 '. An electric motor can also be provided at the end of the first ball screw 31, but in the illustrated embodiment, a manually operated handle is detachably mounted. A first ball nut 35 is screwed into the first ball screw 31 configured as described above, and the ball nut 35 is coupled to the first slide mount 21 via an arm 36. Similarly, a ball nut 35 'is screwed into the second ball screw 31' as shown in part (b) of FIG. 1, and this ball nut 35 'is connected to the arm 36'. And is coupled to the second slide mount 21 ′.

  Next, the operation of the first embodiment will be described. The electric servo motor 33 is activated. As the second ball screw 31 'rotates, the ball nut 35' moves in the axial direction. Since the first and second slide mounts 21 and 21 'are coupled, the coupled movable platform 20 is supported by the linear guide rails 25, 25,. When the first injection unit 11 mounted on the first slide base 21 reaches the first molding position that matches the mold clamping unit 1, for example, a limit switch detects this and the electric servo motor 33 stops. Alternatively, it stops when it reaches a position programmed in the electric servomotor 33. Thus, when the movable mount 20 is driven, the first ball screw 31 is driven to rotate by the moving first ball nut 35. The state stopped at the first molding position is shown in the plan view of FIG. The purge cover is removed from the injection nozzle 13, the first injection unit 11 is advanced, and the injection nozzle 13 is touched on the mold 4. The first injection unit 11 and the mold clamping unit 1 are molded as conventionally known.

  When the movable frame 20 is driven to the first molding position as described above, the second injection unit 11 ′ moves away from the mold clamping unit 1 as shown in the plan view of FIG. . Alternatively, the retracted position is reached. If necessary, the injection nozzle 13 ′ is covered with a purge cover to purge the injection material. Alternatively, maintenance inspection is performed.

  When molding with the second injection unit 11 ′, the first injection unit 11 is moved backward to separate the injection nozzle 13 from the mold 4, and the second ball screw 31 ′ is rotated in the reverse direction by the electric servo motor 33. To drive. The movable gantry 20 moves upward in the plan view of FIG. Similarly, the second injection unit 11 ′ on the second slide base 21 ′ stops at the second molding position where it is aligned with the mold clamping unit 1. This aligned position is shown in the schematic diagram of FIG. The second injection unit 11 ′ is moved forward, the injection nozzle 13 ′ is touched on the mold 4, and the second injection unit 11 ′ and the mold clamping unit 1 are molded as conventionally known. In the second molding position, the first injection unit 11 is retracted from the mold clamping unit 1. As described above, the injection material is purged from the first injection unit 11 or maintenance inspection is performed.

  When the fastening bolts 23, 23,... Are removed and the moving base 20 is separated into the first and second slide bases 21 and 21 ′, the first slide base 21 can be driven by the first ball screw 31. By manually rotating the first ball screw 31 in a predetermined direction by a handle (not shown), the second slide base 21 ′ drives the second ball screw 31 ′ in a predetermined direction by the electric servo motor 33. Thus, they can move independently of each other. If necessary, perform maintenance and inspection by individually driving to the “retraction position”.

  Finally, a second embodiment of the present invention will be described with reference to FIG. Although the present embodiment also includes the mold clamping unit 1 and the injection device 10, the moving base 40 has a substantially fan shape in plan view, and is driven to swing about 60 degrees around the fulcrum O, for example. The first molding position and the second molding position are adopted. That is, the movable mount 40 is composed of first and second fan-shaped slide mounts 41 and 41 ', and the flanges 42 and 42' at the butt edges thereof are fastened and tightened by fastening bolts and nuts 43, 43,. Yes. The apparatus for driving the movable gantry 40 is not particularly limited as in the first embodiment, but in FIG. 3 (a), there is shown a driving device comprising a rack and a pinion or an arc-shaped gear having internal teeth. A drive device comprising a small gear meshing with this is shown. A relatively large first pinion 55 meshes with the arc-shaped first rack 51 attached to the first slide mount 41, and the arc-shaped second rack attached to the second slide mount 41 ′. A small second pinion 55 'meshes with the rack 51'. Also in the second embodiment, the first pinion 55 is driven manually, and the second pinion 55 'is driven by an electric servo motor.

  The first injection unit 11 is mounted on the first slide frame 41 configured as described above, and the second injection unit 11 ′ is mounted on the second slide frame 41 ′ in the same manner as in the above-described embodiment. , And are supported by arc-shaped guide rails 45 having a predetermined length. Although not described in detail, also in the second embodiment, when the first injection unit 11 is driven to the molding position, the second injection unit 11 ′ is driven to the retracted position, and conversely, Obviously, when the injection unit 11 'is driven to the molding position, the first injection unit 11 is driven to the retracted position. Further, when separated into the first and second slide mounts 41 and 41 ′, the first and second racks 51 and 51 ′ and the first and second pinions 55 and 55 ′ can be driven independently. It is also clear that the same operation as in the first embodiment is performed as a whole.

  The injection molding machine according to the present embodiment can be variously modified. For example, it has been described that the purge cover is provided in the injection unit, and the purge cover moves as the injection unit moves, but the purge cover is provided in a fixed position independent of the injection unit so that the injection unit When the retracted position is adopted, the purge cover may be driven to cover the injection nozzle. In addition, the first and second slide mounts have been described as sliding integrally, but they may be slid separately by independent actuators.

DESCRIPTION OF SYMBOLS 1 Clamping unit 10 Injection apparatus 11 1st injection unit 11 '2nd injection unit 13 Injection nozzle 13' Injection nozzle 20 Moving stand
21 1st slide mount 21 '2nd slide mount 25 Linear guide rail
31 1st ball screw 31 '2nd ball screw 40 Moving stand
41 1st slide mount 41 '2nd slide mount 45 Arc-shaped guide rail 51 1st rack 51' 2nd rack 55 1st pinion 55 '2nd pinion

Claims (3)

A fixed plate to which a fixed mold is attached, a movable plate to which a movable mold is attached, a single clamping unit comprising a mold clamping device for opening and closing the movable plate with respect to the fixed plate,
Two first and second injection units comprising a heating cylinder having an injection nozzle at the tip, a screw provided in the heating cylinder so as to be able to be driven in the rotational direction and the axial direction, and a drive device for driving the screw. When,
And a single movable gantry composed of first and second slide gantry that can be driven independently when separated .
With respect to the one mold clamping unit, the two first and second injection units are respectively mounted on the first and second slide mounts of the one moving mount, whereby the moving mount is When driven to the first molding position, the first injection unit takes a molding position aligned with the mold clamping unit, and the second injection unit takes a retracted position separated from the mold clamping unit, When the movable frame is driven to the second molding position, the second injection unit takes a molding position aligned with the mold clamping unit, and the first injection unit is moved away from the mold clamping unit. An injection molding apparatus characterized by adopting 2. The injection molding apparatus according to claim 1, wherein one movable gantry comprising the first and second slide gantry is slidably driven laterally with respect to the mold clamping unit by a ball screw mechanism. Injection molding equipment that takes the molding position of The injection molding apparatus according to claim 1, wherein the first and second slide mounts are independently driven by a ball screw mechanism.

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