JP2002018918A - Mold clamping device for molding disc and method for injection compression molding disc molding using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mold clamping device for molding a disc of a novel structure capable of remarkably improving the degree of freedoms of controlling an operation in the case of injection compression molding. SOLUTION: A core drive means 56 for operating a compression force at a resin material in molding cavity 102 is operable independently of any of a cutter driving mechanism 54 and an ejector driving mechanism 52.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disk forming mold clamping device for forming a disk substrate used for an audio disk, a memory disk, a video disk and the like using a mold, and an injection compression of a disk molded product using the same. It relates to a molding method.

[0002]

2. Description of the Related Art Conventionally, when a disk substrate (disk molded product) for forming an optical disk or a magneto-optical disk is formed, a fixed mold and a movable mold are generally mounted on each of the opposed surfaces of the fixed plate and the movable plate. At least, by the mold driving means,
A disk-forming mold clamping device is used in which the movable platen is driven in the direction of approaching / separating from the fixed platen to perform the mold opening / closing operation and the mold clamping operation. Disc molding is performed by injecting and filling a molten resin material into a molding cavity formed therebetween, cooling and solidifying, then opening both molds and taking out a disc molded product. In addition, to improve the transfer accuracy of pits and grooves to the disk substrate and stabilize optical and mechanical characteristics, the metal mold is slightly opened when the molding cavity is completely filled with the molten resin material. Injection compression molding, in which a greater clamping force is applied to the mold and the movable mold before the molten resin material solidifies to compress and mold the disk substrate, is preferably employed.

In injection compression molding of a disk substrate, the output of the mold driving means exerting a driving force for opening and closing and closing the mold on the movable mold, that is, the mold exerted on the movable mold by the mold driving means. By adjusting the clamping force, it is possible to carry out a mold clamping operation at the time of injection filling of the resin material into the molding cavity and a compression operation after injection filling of the resin material into the molding cavity. As described in Japanese Patent Publication No. 4-70970, etc.,
A core driving means for exerting a compression driving force on a compression core block incorporated in a movable mold is provided separately from a mold driving means for exerting a mold opening / closing and mold clamping force on the movable mold. Mold clamping devices are known. In such a mold clamping device, apart from the mold clamping force exerted between the molds, the compression driving force directly exerted on the core block forming the molding cavity can be adjusted by the core driving means. Therefore, for example, even when a toggle-type mold clamping mechanism is adopted, the mold clamping force at the time of the compression operation can be controlled with high accuracy, and a large compression force can be efficiently applied to the resin material in the molding cavity. It is possible.

However, as described in the above-mentioned publication, in a conventional mold clamping device for injection compression molding, a piston of a hydraulic cylinder mechanism as a core driving means for applying a compression driving force to a compression core block is provided. On the other hand, since a hydraulic cylinder mechanism for cutting the gate formed at the center of the molding cavity and for driving the gate cutter for punching the center hole of the disk molded product is formed, the gate cutter is not protruded. However, when the compression core block alone was not able to be driven and displaced, and before the compression core block was driven for compression to exert a compressive force on the resin material filled in the molding cavity, first, the hydraulic pressure for driving the cutter was first set. The gate mechanism had to be protruded by a cylinder mechanism to shut off the gate.

On the other hand, according to the results of studies by the present inventors, when forming a disk substrate, in addition to the type of resin material to be used, the mold temperature, the time schedule of each molding step, the dimensions of the disk molded product, and the like are determined. Due to the difference, it became clear that it was not always appropriate to apply a compressive force to the resin material after the gate was shut off.In order to obtain the desired characteristics, molding dimensions, etc. with higher precision, it was necessary to use a molding cavity. When it is appropriate to drive the compression core block before the gate cutter is operated after filling the resin material into the gate, or when it is appropriate to drive the compression core block before the gate cutter is completely shut off by the gate cutter It became clear that there was.

However, as described above, the hydraulic cylinder mechanism for exerting the compression driving force on the compression core block and the hydraulic cylinder mechanism for exerting the projecting operation force on the gate cutter are not independently formed. In the mold clamping device, it is necessary to cause the gate cutter to protrude before the compression core block is driven for compression, and the relative timing setting between the compression drive of the compression core block and the projection operation of the gate cutter is greatly restricted. For this reason, there has been a problem that it is extremely difficult to freely set the operation as described above.

[0007]

The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to make the compression drive of a compression core block independent from the projecting operation of a gate cutter. To provide a disk-clamping mold clamping device having a novel structure capable of greatly improving the degree of freedom of injection compression control, and a disk using such a disk-clamping clamping device. An object of the present invention is to provide a novel injection molding method for molded articles.

[0008]

An embodiment of the present invention which has been made to solve such a problem will be described below. The components employed in each of the embodiments described below can be employed in any combination as possible. In addition, aspects or technical features of the present invention are not limited to those described below, but are described in the entire specification and drawings, or based on the invention ideas that can be understood by those skilled in the art from the descriptions. It should be understood that it is recognized on the basis of.

That is, a first aspect of the present invention relating to a disk-forming mold clamping device is to dispose a fixed plate on which a fixed die is mounted and a movable plate on which a movable die is mounted, facing the movable plate. A mold driving means for driving the fixed mold and the movable mold in the approaching / separating direction with respect to the fixed plate, and performing the mold opening / closing operation and the mold clamping operation of the fixed mold and the movable mold. Disk forming mold clamping device provided with a core driving means for applying a driving force to a compression core block to apply a compression force to a filling resin material in a molding cavity formed between a mold mating surface of a fixed mold and a movable mold. At
(A) a cutter driving mechanism for driving a gate cutter that cuts out a central hole of a disk molded product while blocking a gate formed in the center of the molding cavity by being protruded from the movable mold; and (b) the movable. An ejector driving mechanism for driving an ejector pin that is protruded from a mold and releases a disc molded product, provided on the movable platen side, respectively, and the core driving means is provided on the fixed platen or the movable platen, The cutter drive mechanism and the ejector drive mechanism are provided so as to be operable independently of each other.

In the disk forming mold clamping apparatus having the structure according to this aspect, the core driving means for applying a compression driving force to the compression core block to apply a compression force to the resin material in the molding cavity is provided by: Since the cutter drive mechanism and the ejector drive mechanism can be operated independently of each other, during the compression operation on the resin material in the molding cavity, the operation of the core drive means, that is, the compression force exerted on the resin material Can be controlled with great freedom and high accuracy without being restricted by the operation of the cutter drive mechanism, and the like, whereby the resin material and the molding conditions such as temperature can be adjusted. Thus, more desirable compression molding can be performed. Specifically, for example, in addition to (1) operating the gate cutter in a protruding manner to shut off the gate and then compressing the compressed core block, (2) compressing and driving the compressed core block before operating the gate cutter, 3) the compression core block is driven for compression before the gate cutter is completely shut off by the gate cutter, or (4) the compression core block and / or
Alternatively, it is possible to easily operate the gate cutter by changing the speed or the driving force in a plurality of stages.

In this embodiment, the specific structure and arrangement of the cutter driving mechanism, the ejector driving mechanism, and the core driving means are not limited at all. For example, the core driving means may be provided on the fixed platen side. Is also good. Also, the cutter drive mechanism, the ejector drive mechanism, and the core drive means may be configured using various known actuators such as a hydraulic cylinder mechanism, a rotary electric motor mechanism, and a linear motor mechanism as long as required characteristics are achieved. For example, it can be configured to include such an actuator and a driving force transmitting member such as a rod or a link for transmitting an output of the actuator to a gate cutter, an ejector pin, or a compression core block.

A second aspect of the present invention relating to a disk forming mold clamping device is a disk forming mold clamping device having a structure according to the first aspect, wherein the ejector drive is provided on the movable platen side. A drive rod for the ejector pin in the mechanism is disposed on the center axis of the molding cavity, and a drive sleeve for the gate cutter in the cutter drive mechanism is externally inserted into the drive rod for the ejector pin to be coaxial. The driving sleeve of the compression core block in the core driving means is further coaxially arranged by externally inserting the driving sleeve of the gate cutter in the cutter driving mechanism.
Features. In this embodiment, the drive rod of the ejector pin, the drive sleeve of the gate cutter, and the drive sleeve of the compression core block are arranged independently on the same central axis, so that they can be connected to each other. As a whole, it is possible to assemble in a space-saving and compact manner, and furthermore, the overall size of the mold clamping device can be reduced.

A third aspect of the present invention relating to a disk forming mold clamping device is a disk forming mold clamping device having a structure according to the second aspect, wherein the core driving means drives the compression core block. An annular block-shaped piston block is provided on the outer peripheral side of the driving sleeve to form a hydraulic cylinder mechanism for driving the compression core block on the outer peripheral side of the driving sleeve, while the gate in the cutter driving mechanism is provided. The cutter driving sleeve and the ejector pin driving rod of the ejector driving mechanism are respectively disposed so as to protrude rearward in the axial direction from the compression core block driving sleeve of the core driving means. The drive source of the sleeve for driving the gate cutter in the mechanism and the ejector drive The driving source of the driving rod of the ejector pin in the mechanism, both, that is disposed to the rear than the hydraulic cylinder mechanism according compressed core block drive, characterized. In this embodiment, the piston plate is formed integrally with the driving sleeve of the compression core block, and the hydraulic cylinder mechanism for driving is formed on the outer peripheral surface of the compression core block. Side axial length can be kept small. In addition, the gate sleeve driving sleeve and the ejector pin driving rod are projected from the driving sleeve of the compression core block rearward (in the mold opening direction opposite to the mold clamping direction), so that these gate cutters are provided. The space for disposing each drive source of the drive sleeve and the drive rod of the ejector pin can be advantageously secured behind the compression core block. In addition, as the respective drive sources of the drive sleeve of the gate cutter and the drive rod of the ejector pin, various known actuators such as a rotary electric motor, a linear motor, and a pneumatic cylinder mechanism can be employed in addition to a hydraulic cylinder mechanism. .

Further, in the third aspect, more preferably, the gate cutter protrudes rearward from the drive sleeve of the compression core block and protrudes outward from a rear end portion of the drive sleeve. An annular block-shaped piston block is provided, and a hydraulic cylinder mechanism for driving the gate cutter is formed on the outer peripheral side of the driving sleeve of the gate cutter. More preferably, a piston block is provided at a rear end portion of a drive rod of an ejector pin projecting rearward from a drive sleeve of the gate cutter, and a hydraulic cylinder mechanism for driving the ejector pin is configured. . With such a configuration, the hydraulic cylinder mechanism for driving the gate cutter and the hydraulic cylinder mechanism for driving the ejector pin can be formed with excellent space efficiency.

According to a fourth aspect of the present invention, which relates to a disk-forming mold clamping device, there is provided a disk-forming mold clamping device having a structure according to any one of the first to third aspects.
A first position sensor is fixedly attached to the driving sleeve of the compression core block in the core driving means, and the position of the compression core block is directly detected by the first position sensor. That is the feature. In this embodiment, since the position of the compressed core block forming the molding cavity by forming one of the front and back disk molding surfaces can be directly detected by the first position sensor, the disk to be molded is formed. The thickness dimension of the substrate can be detected with higher accuracy, and the improvement of the management accuracy of the product dimension can be easily realized.

In the fourth aspect, a second position sensor for directly detecting a relative position of the movable platen in the approaching / separating direction with respect to the fixed platen is preferably employed. Then, by using the detection signals of the two sensors of the first position sensor and the second position sensor, the relative position of the compressed core block with respect to the fixed mold when the compressed core block is provided on the movable mold side, in other words, Then, the thickness dimension of the molding cavity can be directly detected, whereby the thickness dimension of the disc molded product can be set with higher accuracy.

Further, in the fourth aspect, the core driving means and / or the cutter is provided by utilizing the detection signal of the first position sensor or the detection signals of the first and second position sensors. An operation control device capable of controlling the operation of the drive mechanism based on the position of the compression core block is preferably employed. In such an embodiment, during the compression operation, the thickness dimension of the molding cavity that gives the thickness dimension of the disk molded product is directly detected by the first position sensor or the first and second position sensors. Therefore, it is possible to control the thickness to be the desired thickness, and therefore, compared to the case where the thickness of the disk molded product is controlled based on the conventional compression pressure and operation time, the molding is performed. The thickness of the disk substrate can be controlled more accurately and more stably.

A fifth aspect of the present invention relating to a disk-forming mold clamping device is a disk-forming mold clamping device structured according to any one of the first to fourth aspects,
On the opposing surfaces of the fixed plate and the movable plate, at least one side protrudes from the other side to limit the relative approach amount between the fixed plate and the movable plate by abutting on the other side. While the mold clamping stopper is provided, the entire movable mold is supported so as to be movable from the movable plate toward the fixed plate, and the fixed platen and the movable platen are relatively positioned by the mold clamping stopper. Under this condition, the core driving means compresses and drives the entire movable mold as the core block in the approaching direction with respect to the fixed mold. In this embodiment,
Because the movable mold is mounted so that it can be displaced in the compression direction as a whole without fixing the movable mold to the movable plate, a special structure mold that incorporates a separate compression core block inside is required. Instead, it is possible to perform injection compression molding using a conventional movable mold having an integral structure. It is desirable that the movable plate is provided with a guide mechanism for guiding the movable mold in the mold opening and closing direction. The mold stopper may be provided on only one of the fixed plate and the movable plate. The protruding tip surfaces of the both mold clamping stoppers may be brought into contact with each other.

Further, the present invention relating to the injection compression molding method of a disk molded product is characterized in that the disk is formed by using the disk forming mold clamping device having the structure according to the present invention according to any one of the first to fifth aspects as described above. When molding molded products,
After injecting and filling a resin material into a molding cavity formed between the fixed mold and the movable mold under a mold clamping state of the fixed platen and the movable platen, the core drive means The compression core block is compressed and displaced toward the molding cavity, and the gate driving mechanism is caused to protrude into the molding cavity by the cutter driving mechanism with a delay from the compression displacement of the compression core block.

According to the method of the present invention, at the start of the compression displacement of the compression core block, since the gate is kept sufficiently open, the compression is performed until the molding cavity reaches a predetermined thickness. The core block is quickly displaced, and then the gate is closed and a compressive force is applied to the resin material to stably mold the disk of the desired size while exerting an effective compression action. It is possible to do. In the present invention,
The timing of closing the gate by causing the gate cutter to protrude can be appropriately set according to the resin material to be used, molding conditions such as mold temperature, and the like.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, in order to clarify the present invention more specifically, embodiments of the present invention will be described in detail with reference to the drawings.

First, FIGS. 1 to 3 show a disk forming mold clamping apparatus according to a first embodiment of the present invention.
The mold clamping device includes a fixed plate 12 and a pressure receiving plate 14 which are respectively fixed on a base 10 and are opposed to each other at a predetermined distance, and between the opposed surfaces of the fixed plate 12 and the pressure receiving plate 14. The movable plate 16 is disposed, and the movable plate 16 is guided by a plurality of tie rods 18 disposed between the fixed plate 12 and the pressure receiving plate 14, so that the movable plate 16 And can be displaced in the approach / separation direction. A fixed mold 20 is fixedly attached to a surface of the fixed plate 12 facing the movable plate 16, and a movable mold 22 is fixed to a surface of the movable plate 16 opposed to the fixed plate 12. It can be attached to.

More specifically, the fixed platen 12 has a thick, substantially rectangular flat plate shape, and is fixed to the base 10 via a spacer 23. A nozzle insertion hole 24 is formed in the center of the fixed platen 12 so as to penetrate in the axial direction. Then, the nozzle portion 26 of the separate injection device is inserted into the nozzle insertion hole 24, and the fixed mold 20 is inserted.
The nozzle is touched. On the other hand, the pressure receiving plate 14 is provided with a main cylinder 28 that opens toward the fixed plate 12, and a rectangular flange-like portion 30 that extends in the direction perpendicular to the axis at the peripheral edge of the opening of the main cylinder 28 to form an outer flange. Similarly to the fixed plate 12, it is fixed to the base 10 with the spacer 29 interposed therebetween.

A main ram 32 is slidably inserted into the main cylinder 28 of the pressure receiving plate 14 and is assembled therein. Although not explicitly shown in the drawing, the main ram 32 is provided inside the pressure receiving plate 14. A main cylinder chamber for driving the ram 32 to project toward the fixed platen 12 and a retreating cylinder chamber 34 for driving the main ram 32 to retreat are formed.

The main ram 32 is formed with a booster cylinder chamber 36 which opens toward the main cylinder chamber.
A cylindrical booster ram 38 projecting from the bottom wall of the cylinder 4 is slidably fitted therein. Hydraulic oil is supplied to the booster cylinder chamber 36 through the hollow hole of the booster ram 38 to thereby fix the main ram 32 to the fixed platen. A booster cylinder mechanism 40 for closing the mold at high speed toward 12 is configured.

An intermediate block 42 is fixed to the protruding tip of the main ram 32, and the movable plate 16 is fixed so as to be relatively immovable via spacers 43, 43 and a seal block 44. ing. Accordingly, the main ram 32 is driven in the axial direction based on the supply and discharge of the hydraulic oil to the main cylinder chamber, the retreat-side cylinder chamber 34, and the booster cylinder chamber 36, so that the movable plate 16 is moved to the fixed plate 12. On the other hand, it is driven in the approach / separation direction. In short, in the present embodiment, the main cylinder mechanism constituted by the main ram 32, the main cylinder chamber and the retraction cylinder chamber 34, and the booster cylinder mechanism 40 constituted by the main ram 32, the booster ram 38 and the booster cylinder chamber 36. The mold driving means is configured to cause the fixed mold 20 and the movable mold 22 to perform the mold opening / closing operation and the mold clamping operation.

Further, central holes 46, 48 and 50 are formed in the intermediate block 42, the seal block 44 and the movable plate 16 fixedly provided at the tip of the main ram 32 so as to extend through the central portion in the axial direction. And their central holes 4
6, 48, 50, and ejector drive rod 5
2, cutter drive sleeve 54 and core drive sleeve 5
6 are arranged so as to be movable in the axial direction. That is,
The ejector drive rod 52 has a straight solid rod shape as a whole, and is disposed on the central axis of the movable mold 22 and the fixed mold 20 so as to be movable in the axial direction so as to extend in the mold opening and closing direction. Have been. Further, the cutter driving sleeve 54 has a straight hollow cylindrical shape as a whole, and is disposed outside the ejector driving rod 52 so as to be movable in the axial direction. Further, the core drive sleeve 56 has a cylindrical shape with a larger diameter than the cutter drive sleeve 54, and is arranged outside the cutter drive sleeve 54 so as to be movable in the axial direction. In short, the ejector drive rod 52, the cutter drive sleeve 54, and the core drive sleeve 56 can be axially displaced coaxially and independently on the central axis of the mold clamping device, and
It is assembled on the 6 side.

The cutter drive sleeve 54 has a longer axial length than the core drive sleeve 56, and the ejector drive rod 52 is longer in the axial direction than the cutter drive sleeve 54. It has been. The ejector drive rod 52, the cutter drive sleeve 54, and the core drive sleeve 56 are arranged such that their respective axial end surfaces (axial end surfaces on the fixed platen 12 side) are substantially flush with each other. So that at the other axial end, the core drive sleeve 56
An open end behind the cutter drive sleeve 54 is protruded from the rear open end of the cutter drive sleeve 54 by a predetermined length in the axial direction, and an ejector drive rod 52 is provided in the axial direction from the rear open end of the cutter drive sleeve 54 in a predetermined direction. It is protruded by the length. In the present embodiment, the core drive sleeve 56 has an axial length extending through the movable plate 16 and near the intermediate block 42, and the cutter drive sleeve 54 connects the movable plate 16 and the intermediate block 42 to each other. The ejector drive rod 52 extends through the movable platen 1 near the main ram 32.
6 and the intermediate block 42, and further into the main ram 32. The ejector drive rod 52 is constituted by a plurality of divided rods fixedly connected to each other in the axial direction.

Further, an ejector cylinder chamber 5 is provided at an axial end portion (right end portion in FIG. 1) of the main ram 32.
8 are formed, and the ejector cylinder chamber 58
An ejector piston 60 integrally formed at the rear end of the ejector drive rod 52 is slidably assembled with the ejector drive rod 52, and a double-acting hydraulic cylinder mechanism for an ejector that reciprocates the ejector drive rod 52 in the axial direction. 62 are configured.

In the intermediate block 42, a cutter cylinder chamber 64 is formed by the center hole 46. The cutter drive chamber projecting rearward from the core drive sleeve 56 with respect to the cutter cylinder chamber 64 is formed. Sleeve 5
4, a cutter piston 66 protruding radially outward.
Is slidably mounted. Thus, a double-acting cutter hydraulic cylinder mechanism 68 for driving the cutter drive sleeve 54 to move forward and backward in the axial direction is configured.

Further, a core cylinder chamber 70 is formed by the center hole 50 of the movable platen 16, and a core cylinder chamber 70 protruding from the outer peripheral surface of the core driving sleeve 56 is formed in the core cylinder chamber 70. A piston 72 is mounted. As a result, a core hydraulic cylinder mechanism 74 that drives the core drive sleeve 56 forward / backward in the axial direction by supplying and distributing hydraulic oil is configured.

As shown in FIG. 1, the ejector, cutter, and core hydraulic cylinder mechanisms 62, 68, 74 correspond to the ejector, cutter, and core four-way switching valves 76, respectively. , 78,80
, The hydraulic pump 82 and the drain 84 are connected to each other, so that the four-way switching valves 76, 78, 8
0, the ejector drive rod 52, the cutter drive sleeve 54, and the core drive sleeve 56
It is designed to be appropriately driven forward / backward independently of each other. In addition, at the rear end in the axial direction of the core drive sleeve 56, a longitudinally arranged movable by a predetermined amount in the axial direction in the movable space formed between the movable plate 16 and the intermediate block 42 by the spacers 43, 43. A movable plate 86 is fixed by bolts, and the axial position of the core drive sleeve 56 can be confirmed from the outside by the movable plate 86. In particular, in the present embodiment, a first sensor head 88 for magnetic detection is fixed to the projecting tip of the moving plate 86, and the position of the sensor head 88 is fixed to the intermediate block 42 by bolts. The position is detected by the first magnetic scale 90. In short, the first sensor head 88 fixed to the moving plate 86 and the intermediate block 42
The first magnetic scale 90 fixed to the movable plate 16 constitutes a first magnetic scale 92 as a first position sensor for detecting the axial position of the core drive sleeve 56 with respect to the movable plate 16. .

Further, in the present embodiment, a second sensor head 96 for magnetic detection is fixed to a support rod 94 protruding from the base 10, and the second sensor head 96 is fixed to the support rod 94. A second magnetic scale 98 for detecting the position of 96 is fixed to the movable platen 16, and the second sensor head 96 and the second magnetic scale 98 allow the base 10 and the fixed platen 12 to move relative to each other. Movable board 16
The second magnescale 100 is configured as a second position sensor for detecting a position in the relative approach / separation direction.

In the mold clamping device having such a structure, as shown by phantom lines in FIGS.
The fixed mold 2 is provided on the surface of the fixed plate 12 facing the movable plate 16.
0 is fixedly mounted, while a movable mold 22 is fixedly mounted on a surface of the movable platen 16 facing the fixed platen 12. The movable platen 1 is moved by the booster cylinder mechanism 40 and the main cylinder mechanism.
The fixed mold 20 and the movable mold 22 are opened / closed and clamped by driving and displacing the fixed plate 6 in the approaching / separating direction with respect to the fixed plate 12.

The fixed mold 20 and the movable mold 2
Under the mold clamping state of 2, between the mating surfaces of both molds 20 and 22,
The desired molding cavity 102 of the disk substrate (FIG. 5)
With respect to the molding cavity 102, the nozzle portion 26 of the separate injection device is brought into nozzle contact with the fixed mold 20 through the nozzle insertion hole 24 of the fixed plate 12. By injecting and filling a molten resin into the disk molding cavity 102 therefrom, a target disk molded product is molded.

As shown in FIG. 4, a movable core 22 has a compression core block 104 incorporated therein so as to be movable in a mold clamping direction. This compressed core block 104 forms one molding surface of a disk molded product, and has a central portion,
It has a through hole 106 extending in the axial direction. Then, a rod-shaped ejector pin 108 disposed on the center axis and the ejector pin 10
8, a thick cylindrical gate cutter 110 extrapolated to 8,
Further, a cylindrical ejector sleeve 112 externally inserted into the gate cutter 110 is accommodated and arranged. The ejector pins 108, the gate cutter 110, and the ejector sleeve 112 are all mounted on the movable mold 22 so as to be movable independently of each other in the axial direction. Then, the ejector pin 108 and the ejector sleeve 112 are moved by the ejector drive rod 52.
The gate cutter 110 is driven to protrude with respect to the movable platen 16.
Driven in the protruding direction. Furthermore, the compressed core block 104 is driven to protrude in the axial direction by a core drive sleeve 56 assembled to the movable platen 16. The driving structure of the ejector pin 108 and the ejector sleeve 112 by the ejector driving rod 52 and the driving structure of the gate cutter 110 by the cutter driving sleeve 54 are not necessarily shown in FIG. It can be easily realized by adopting a known structure disclosed in Japanese Patent No. 2804394, so that detailed description is omitted here.

Next, a description will be given of a disk forming method using the mold clamping device having the above-mentioned structure with reference to model diagrams of FIGS.

That is, first, as shown in FIG. 4, the ejector pin 108 and the ejector sleeve 11
2. Gate cutter 110 and compression core block 104
Is held in a retracted position separated from the fixed platen 12, and the main ram 32 is set in a mold open state in which the main ram 32 is retracted. In such a mold open state, the cutter drive sleeve 54 and the core drive sleeve 56 are both located at the retracted position, that is, at the moving end in the direction away from the fixed platen 12.

Then, from the mold open state, as shown in FIG. 5, the high-speed mold closing operation is performed by the booster cylinder mechanism 40 (see FIG. 1), and then the mold clamping operation is performed by the main cylinder mechanism. As a result, the fixed mold and the movable mold are matched to each other and held in a mold-clamped state. Then, by clamping the mold, a disc molding cavity 102 is formed between the mold mating surfaces of the fixed mold 20 and the movable mold 22. As shown in the figure, the molding cavity on the movable mold 22 side of one of the disk molding surfaces of the disk molding cavity 102 is formed by the axial end surface of the compression core block 104 over substantially the entirety. Although not explicitly shown in the drawings, a stamper on which predetermined information is engraved is mounted on at least one of the molding surfaces of the fixed mold 20 and the movable mold 22.

Thereafter, as shown in FIG. 6, the sprue 114 attached to the center hole 116 of the fixed mold 20 is formed.
Nozzle part 26 of the injection device that made nozzle touch
Through the sprue hole to the molding cavity 102 for injection filling.

Subsequently, as shown in FIG. 7, during the step of injecting the molten resin material, the core driving sleeve 56 is driven to the projecting front side (toward the fixed mold 20) to move the compressed core block 104. By driving to the fixed platen 12 side, a compression action is started to be applied to the molten resin material filled in the molding cavity 102.

Thereafter, as shown in FIG. 8, the cutter driving sleeve 54 is driven forward to delay the operation of the core hydraulic cylinder mechanism 74 (see FIG. 1).
The projecting operation of the gate cutter 110 is started. The start of the projecting operation of the gate cutter 110 is determined by, for example, the position of the core drive sleeve 56 detected by the first and second magnescales 92 and 100 (see FIGS. 1 and 2), and thus the position of the compression core block 104. Is started by reaching a preset position. Alternatively, compressed core block 1
Time measurement is started from the start of the projecting operation of 04, and the projecting operation of the gate cutter 110 is started with a delay of a preset predetermined time.

Then, the gate cutter 110 is protruded to be fitted into the center hole 116 of the fixed mold 20. This shuts off the annular gate formed at the center of the disk. At the same time, the resin material filled in the sprue 114 and the like of the fixed mold 20 is separated from the resin material filled in the molding cavity 102 by penetrating the gate cutter 110 in the center of the disk. An annular disk-shaped disk forming area is formed in the forming cavity 102 by punching and forming 118.

Thereafter, the core drive sleeve 56 is further caused to protrude toward the advancing side to apply a compressive force to the resin material filled in the molding cavity 102. In short, under the state where the gate is shut off, the molding cavity is in a closed state, and the forward drive of the compression core block 104 causes
An effective compressive force is exerted on the filled resin material.

After a predetermined cooling time has elapsed, the fixed mold 20 is separated from the movable mold 22 to open the mold by driving the main ram 32 backward as shown in FIG. At the same time, the ejector hydraulic cylinder mechanism 62 (see FIG. 1) is operated to protrude, and the ejector drive rod 52 causes the ejector pin 108 and the ejector sleeve 112 to operate to protrude. The base (121) is released from the mold and taken out. The ejecting operation of the ejector pin 108 and the ejector sleeve 112 by the ejector drive rod 52 is performed with a predetermined time difference, that is, slightly later than the ejector pin 108.
2 to protrude, whereby
The runner portion and the disk molded product are stably released from each other and collected.

That is, in the mold clamping device having the structure according to the present embodiment as described above, the ejector hydraulic cylinder mechanism 62, the cutter hydraulic cylinder mechanism 68, and the core hydraulic cylinder mechanism operable independently of each other. When the disk molding is injection-molded, the timing at which the compression core block 104 is projected and the timing at which the gate cutter 110 is projected can be separately set. As in the above-described embodiment, the compression core block 104 is caused to protrude at an appropriate time during the injection and filling operation of the molten resin material, and then the gate cutter 110 is protruded with a delay and the gate of the molding cavity 102 is shut off. When the compression core block 104 is operated to protrude,
It can be molded by completing the compression. Therefore, the operation timing of the compression core block 104 and the gate cutter 110 is set with a large degree of freedom according to various molding conditions such as the type of resin material to be employed, cooling conditions, mold temperature, temperature of the molten resin material, and the like. This makes it possible to more stably mold the desired disk molded product with higher quality.

Further, in the mold clamping device of the present embodiment, the position of the compression core block 104 is directly detected by the first magnescale 92.
By controlling the compression core block 104 by controlling the four-way switching valve 80 based on such detection specifications, it is possible to directly and accurately set the thickness dimension of the target disk molded product. is there.

Next, FIGS. 10 to 15 schematically show an injection compression process as a second embodiment of a disk molded product using the disk molding die clamping device according to the present invention as described above. I have. In the present embodiment, a mold clamping device similar to that of the first embodiment is employed, which is a specific example in which a mounted mold structure is different. Only the parts will be illustrated and described. Further, in the present embodiment, members and parts having the same structure as the disk forming mold clamping device of the first embodiment are denoted by the same reference numerals in the drawings as those of the first embodiment. Thus, detailed description thereof will be omitted.

That is, in the present embodiment, the mold block 120 attached to the movable platen 16 does not include the movable compression core block (104) as in the above-described embodiment, but has an integral fixed structure as a whole. Have been. The mold block 120 is mounted on the movable platen 16 via a mold plate 122 fixed on the rear side. In this case, the movable mold 124 is mounted so as to be relatively displaceable in the mold opening and closing direction by a plurality of guide pins 126 protruding from a surface of the movable board 16 facing the fixed board 12. Reference numeral 124 as a whole is attached to the movable plate 16 so as to be relatively displaceable by a predetermined amount in the mold opening and closing direction. In short, in the present embodiment, the entire movable mold 124 including the mold block 120 and the mold plate 122 is a compression core block. The fixed mold (20) is fixedly attached to the fixed platen 12 with bolts or the like, as in the first embodiment.

On the other hand, on opposing surfaces of the fixed platen 12 and the movable platen 16, a mold clamping stopper 128 protruding at a predetermined height in the opposing direction on the outer peripheral portion of the fixed die 20 and the movable die 124. , 129 are fixedly provided. Then, as shown in FIG.
When the mold is closed with respect to the fixed platen 12, the protruding tip surfaces of the mold clamping stoppers 128 and 129 come into contact with each other to define the approaching position of the movable platen 16 to the fixed platen 12, and the mold closing state is determined. The relative separation distance between the fixed platen 12 and the movable platen 16 is set. Further, in the mold clamping state in which the stoppers 128 and 129 are brought into contact with each other, a slight gap (compression gap: δ) is formed between the opposed surfaces of the fixed mold 20 and the movable mold 124. I have.

Accordingly, in the mold clamping apparatus having the fixed mold 20 and the movable mold 124 having such a structure, the molten resin material is introduced into the molding cavity 102 to form a disk molded product. As shown in FIG. 12, after the molten resin is filled, as shown in FIG. 13, the core hydraulic cylinder mechanism 74 (see FIG. 1) is operated to cause the core drive sleeve 56 to operate to protrude. As a result, the entire movable mold 124 is operated to be compressed away from the movable platen 16 toward the fixed mold 20 by the compression stroke: δ corresponding to the compression gap.

Accordingly, in the mold clamping apparatus and the compression molding method according to the present embodiment as described above, as shown in FIGS. In accordance with the same operation, the disk molded article 121 can be injection-compressed, and thereby,
The same effects as those of the first embodiment can be effectively exhibited.

Further, in this embodiment, in particular, the movable mold 12
There is no need to adopt a special structure in which a separate compression core block is specially incorporated as 4, and there is an advantage that a movable mold having an integral structure can be employed as in the conventional case.

The embodiment of the present invention has been described above in detail, but this is merely an example.
By the specific description in such an embodiment,
It cannot be construed as limiting.

For example, in the above-described embodiment, the booster type hydraulic cylinder mechanism is used as the mold driving means for driving the movable plate. However, other hydraulic cylinder mechanisms using a toggle mechanism, or electric type metal molds are used. It is also possible to employ a mold driving means, or a hybrid mold driving means using both a hydraulic type and an electric type.

In the above embodiment, the compressed core block exerting a compressive force on the filled resin material is provided by the movable molds 22 and 12.
Although the compression core block is mounted on the side of the fixed mold 20, it is also possible to mount the compression core block on the side of the fixed mold 20. When the compression block is provided on the fixed mold 20 side, a core driving means or the like for exerting a driving force on the compression block is also provided on the fixed mold 20 side.

In the above embodiment, the single disk molding cavity 10 is fixed between the fixed mold 20 and the movable mold 22.
2 is formed, but it is also possible to form a plurality of disc molding cavities between the mold mating surfaces of the fixed mold 20 and the movable mold 22, and such a multi-cavity mold clamping apparatus for injection molding. Needless to say, the present invention can be similarly applied to the injection compression molding method. When applying the present invention to such a multi-disc molding die clamping device for a disk, for each molding cavity,
It is desirable that a cutter drive mechanism, a core drive mechanism, and an ejector drive mechanism be provided so that they can be independently controlled.

Further, the position sensor for detecting the position of the compression core block is not limited to the magnescale as illustrated, but may be any of various known sensors such as a predetermined meter, a wave transformer, and a semiconductor resistance displacement sensor. The position detection sensor described above can be appropriately adopted.

In addition, although not enumerated one by one, the present invention
Based on the knowledge of those skilled in the art, various changes, modifications, improvements and the like can be performed in embodiments, and unless such embodiments depart from the spirit of the present invention.
Both are included in the scope of the present invention,
Needless to say.

[0060]

As is apparent from the above description, in the disk-clamping apparatus having the structure according to the present invention, the core driving means for applying a compressive force to the molten resin material filled in the molding cavity. However, since the operation can be controlled independently of the cutter drive mechanism that shuts off the gate, suitable molding operation conditions can be set with great flexibility according to various injection conditions such as resin material and molding temperature. Therefore, the quality and stability of the manufactured disk molded product can be advantageously improved.

Further, according to the injection compression molding method for a disk molded product of the present invention, the timing for projecting the compression core block and the timing for projecting the gate cutter can be set independently of each other.
For example, the compression core block is protruded at an appropriate time during the injection operation of the molten resin material, and then the gate cutter is protruded with a delay, the gate of the molding cavity is shut off, and then the compression core block is protruded. It is also possible to complete the compression by pressing the compression core block or gate cutter according to various molding conditions such as the type of resin material used, cooling conditions, mold temperature, temperature of the molten resin material, etc. It is possible to set with a large degree of freedom, and it is possible to stably mold a disk molded product of a desired size while exerting an effective compressing action on the resin material in the molding cavity. is there.

[Brief description of the drawings]

FIG. 1 is an explanatory longitudinal sectional view of a compression molding apparatus for molding a disk as a first embodiment of the present invention.

FIG. 2 is a front view of the disk mold compression mold clamping device shown in FIG.

FIG. 3 is a sectional view taken along line III-III in FIG.

FIG. 4 is a model diagram showing one molding step when molding a disk molded product using the disk molding compression mold clamping device shown in FIG.

FIG. 5 is a model diagram showing one molding step when molding a disk molded product using the disk molding compression mold clamping device shown in FIG. 1;

FIG. 6 is a model diagram showing one molding step when molding a disk molded product using the disk molding compression mold clamping device shown in FIG.

FIG. 7 is a model diagram showing one molding step when molding a disk molded product using the disk molding compression mold clamping device shown in FIG.

FIG. 8 is a model diagram showing one molding step when molding a disk molded product using the disk molding compression mold clamping device shown in FIG.

FIG. 9 is a model diagram showing one molding process when molding a disk molded product using the disk molding compression mold clamping device shown in FIG.

FIG. 10 is a model diagram corresponding to FIG. 4, showing a main part of a compression mold clamping device for disk molding as a second embodiment of the present invention.

FIG. 11 is a model diagram showing one molding step when molding a disk molded product using the disk molding compression mold clamping device shown in FIG.

FIG. 12 is a model diagram showing one molding process when molding a disk molded product using the disk molding compression mold clamping device shown in FIG.

FIG. 13 is a model diagram showing one molding step when molding a disk molded product using the disk molding compression mold clamping device shown in FIG.

FIG. 14 is a model diagram showing one molding step when molding a disk molded product using the disk molding compression mold clamping device shown in FIG.

FIG. 15 is a model diagram showing one molding step when molding a disk molded product using the disk molding compression mold clamping device shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 12 Fixed board 16 Movable board 20 Fixed mold 22 Movable mold 52 Ejector drive rod 54 Cutter drive sleeve 56 Core drive sleeve 58 Ejector cylinder chamber 60 Ejector piston 62 Ejector hydraulic cylinder mechanism 64 Cutter cylinder chamber 66 Cutter piston 68 Cutter Hydraulic cylinder mechanism 70 core cylinder chamber 72 core piston 74 core hydraulic cylinder mechanism 104 compression core block 124 movable mold

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G11B 7/26 511 G11B 7/26 511 521 521 // B29L 17:00 B29L 17:00 F term (Reference) 4F202 AH38 AH79 AP06 CA11 CB01 CK06 CK18 CK35 CK42 CK74 CK84 CM02 4F206 AH38 AH79 AP06 JA07 JL02 JM05 JM06 JN25 JN41 JP11 JQ81 JT06 JT07 JT11 JT21 5D121 AA02 DD05 DD18

Claims (7)

[Claims] 1. A mold for disposing a fixed plate on which a fixed die is mounted and a movable plate on which a movable die is mounted, and driving the movable plate in a direction of approaching / separating from the fixed plate. Driving means is provided to open / close and clamp the fixed mold and the movable mold, and to apply a driving force to the fixed mold or the compression core block of the movable mold to cause the fixed mold and the movable mold to move. In a disk-molding mold clamping device provided with a core driving means for applying a compressive force to a filling resin material in a molding cavity formed between the mold mating surfaces of a mold, the molding cavity of the molding cavity is protruded from the movable mold. A cutter driving mechanism for driving a gate cutter that cuts off a gate formed at the center and punches a center hole of the disk molded product; and releases the disk molded product by being protruded from the movable mold. An ejector driving mechanism for driving an ejector pin is provided on the movable platen side, and the core driving means is independent of any of the cutter driving mechanism and the ejector driving mechanism on the fixed platen or the movable platen. A disk forming mold clamping device characterized in that it is operably provided. 2. On the movable platen side, a drive rod for the ejector pin of the ejector drive mechanism is disposed on a center axis of the molding cavity,
A driving sleeve of the gate cutter in the cutter driving mechanism is externally inserted into a driving rod of the ejector pin and arranged coaxially, and further, a driving sleeve of the compression core block in the core driving means is provided. 2. The disk-clamping mold clamping device according to claim 1, wherein the disk-clamping device is externally inserted into a driving sleeve of the gate cutter in the cutter driving mechanism and coaxially disposed. 3. A driving block for the compression core block in the core driving means, wherein an annular block-shaped piston block protruding to the outer peripheral side is provided on the outer peripheral side of the driving sleeve. A hydraulic cylinder mechanism, a driving sleeve of the gate cutter in the cutter driving mechanism, and a driving rod of the ejector pin in the ejector driving mechanism, respectively, for driving a compression core block in the core driving means. The compression core is disposed so as to protrude rearward in the axial direction from the sleeve, and the drive source of the sleeve for driving the gate cutter in the cutter drive mechanism and the drive source of the rod for driving the ejector pin in the ejector drive mechanism are both compressed cores. Arranged behind the hydraulic cylinder mechanism for block drive 3. The disk-clamping mold clamping device according to claim 2. 4. A first position sensor is fixedly attached to a driving sleeve of the compression core block in the core driving means, and the position of the compression core block is directly controlled by the first position sensor. 4. The disk-clamping mold clamping device according to claim 1, wherein the disk-clamping device detects the force. 5. An operation capable of controlling the operation of the core driving means and / or the cutter driving mechanism based on the position of the compression core block by using a detection signal of the first position sensor. 5. The disk forming mold clamping device according to claim 4, further comprising a control device. 6. The opposed surface of the fixed platen and the movable platen is protruded from at least one side toward the other side, and is brought into contact with the other side to make the relative position between the fixed platen and the movable platen. While providing a mold-clamping stopper for restricting the approach amount, the movable mold is entirely supported movably from the movable plate toward the fixed platen, and a fixed platen relatively positioned by the mold-clamping stopper is provided. 6. The movable driving die as a core block is compressed and driven in the direction of approach to the fixed die by the core driving means under the closed state of the movable platen. The mold clamping device for forming a disk according to item 1. 7. When a disk molded product is molded by using the disk molding die clamping device according to claim 1, the fixed die is formed under the clamped state of the fixed platen and the movable platen. After the resin material is injected and filled into the molding cavity formed between the mold mating surfaces of the movable mold and the movable mold, the compressed core block is compressed and displaced toward the molding cavity by the core driving means. An injection compression molding method for a disk molded product, characterized in that the gate cutter is caused to protrude into the molding cavity by the cutter driving mechanism after a delay of the compression displacement of the block.