KR20010026358A - Gate cut apparatus and method for a disc molding apparatus - Google Patents

Abstract

PURPOSE: A device and a method for gate cut are provided not to generate differential stains and forming defects in a disk by a mold opening. CONSTITUTION: A gate cut device comprises a fixing mold(12); an operating mold(32) to be freely moved forward and backward by facing to the fixing mold and to form a cavity space between the fixing mold; a spool(26) installed toward the cavity space and to be formed a depressed portion(28) to be entered a cut punch(48); a driving portion to move the cut punch forward and backward; and a controller of the driving portion to perform a gate cut by advancing the cut punch through extruding force and to reduce the extruding force under a set value before a mold opening. Thereby, the operating mold is not moved backward with maintaining the extruding force. Therefore, differential stains and forming defects are prevented.

Description

Gate cut apparatus and method for a disc molding apparatus

The present invention relates to a gate cut device and a gate cut method of a disk forming apparatus.

Conventionally, in an injection molding machine, a resin, which is heated and melted in a heating cylinder, is filled in a cavity space of a mold apparatus, cooled in the cavity space, and solidified, and then the molded article is taken out.

To this end, a screw is installed in the heating cylinder, and when the screw is advanced, the resin is injected from the injection nozzle provided at the front end of the heating cylinder. The injected resin enters the cavity space through the spool and the gate.

However, in the disk forming apparatus for forming a disk, a gate cut device is installed to remove the molding substrate and the gate in the cavity space and to punch the center of the molding substrate after the resin is filled in the cavity space. do.

Then, the gate cut device is driven before the resin in the cavity space is solidified, and a mold opening is performed while the cut punch is protruded to maintain the extrusion force so that the disc is taken out.

However, in the gate cut device of the conventional disk forming apparatus, since the extrusion force is maintained when the mold opening is performed, mold opening cannot be performed at the timing, speed, or the like as set, and mold release unevenness occurs on the disk. Defects may occur.

The present invention provides a gate cut device and a gate cut method of a disk forming apparatus that can solve the problem of the gate cut apparatus of the conventional disk forming apparatus and prevent mold defects from occurring due to mold release. It aims to do it.

1 is a mold opening state diagram of a disk forming apparatus in an embodiment of the present invention;

2 is a conceptual diagram of a gate cut device in an embodiment of the present invention.

To this end, in the gate-cutting device of the disk forming apparatus of the present invention, the cavity is fixed between the stationary mold and the stationary mold in a state in which the forward and rearward sides are freely installed and mold clamping is performed to face the stationary mold. A movable mold for forming a space, a spool having a recess formed to face the cavity space and having a recess into which the cut punch enters the tip, a cut punch provided freely in the front and rear direction toward the cavity space and facing the recess; And a cut to drive the drive back and forth, and drive the drive to advance the cut punch with a predetermined extrusion force to perform a gate cut, and extrude the cut punch before the mold is opened. It has a drive part control means which makes it smaller than a set value.

In this case, since the extrusion force of the cut punch becomes smaller than the set value before mold opening is performed, the movable mold is not retracted while the extrusion force is maintained. Therefore, since the movable mold can be retracted at the timing, speed, or the like as set, it is possible to prevent mold defects from occurring due to mold release unevenness on the disk due to mold opening.

In the gate cut apparatus of another disk forming apparatus of the present invention, the drive portion is also a gate cut cylinder, and the drive portion control means extracts oil in the oil chamber of the gate cut cylinder before the mold opening is performed.

In the gate cut device of another disc forming apparatus of the present invention, the drive portion is also a gate cut motor, and the drive portion control means reduces or stops the supply of current to the gate cut motor before the mold opening is performed.

In the gate-cutting method of the disk forming apparatus of the present invention, the movable mold is pressed into the stationary mold to perform mold cutting, and the gate cut is performed by advancing a cut punch provided toward the cavity space while the mold is being performed, and pressing the cut punch. After making the output smaller than the set value, the mold is opened.

The structures and features of the gate cut device and gate cut method of the disk forming apparatus of the present invention will become apparent by referring to the following drawings.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a mold opening state diagram of a disk forming apparatus in an embodiment of the present invention, and Fig. 2 is a conceptual diagram of a gate cut device in an embodiment of the present invention.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described in detail, referring drawings.

1 is a mold opening state diagram of a disk forming apparatus in an embodiment of the present invention.

In the figure, 11 is a stationary platen and 12 is a stationary side assembly as a stationary mold attached to the stationary platen 11 by bolts 13. The fixed side assembly 12 includes a fixed side base plate (15), a fixed side disc plate (16) fixed to the fixed side base plate (15) by bolts (17), and a fixed side disc plate ( 16, an annular fixed side guide ring 18 fixed to the fixed side base plate 15 by a bolt 19, and a fixed platen 11 of the fixed side base plate 15; With a locating ring 23 installed on the side and positioning the fixed side base plate 15 relative to the fixed platen 11 and a spool bush 24 provided adjacent to the locating ring 23. Is done.

At the center of the spool bush 24 is formed a spool 26 for passing resin injected from an injection nozzle (not shown). Further, the tip (left end in the drawing) of the spool bush 24 is formed with a recess, ie, a die 28, into which the cut punch 48 enters the tip toward the cavity space (not shown).

The fixed side assembly 12 is also provided with a stamper plate attaching and detaching bush, a fixed side air blow bush, and the like, which are not shown.

On the other hand, 31 is a movable platen and 32 is a movable side assembly as a movable mold attached to the movable platen 31 by a bolt 33. The movable side assembly 32 includes a movable side base plate 35, an intermediate plate 40 fixed to the movable side base plate 35 by a bolt 37, and a bolt 42 on the intermediate plate 40. Movable side disk plate 36 fixed by means of the annular movable side guide ring 38 installed on the outer circumference of the movable side disk plate 36 and fixed to the intermediate plate 40 by bolts 39. And a spooling holder 44 and a rear portion of the spooling holder 44 installed in the movable side base plate 35 facing the movable platen 31 and fixed to the intermediate plate 40 by bolts 45. It consists of a cut punch 48 which is held by and whose front end has a shape corresponding to that of the die 28 toward the cavity space, in which forward and backward movements are freely installed.

In addition, a concave portion 50 is formed on a surface of the movable side disc plate 36 facing the fixed side disc plate 16. Therefore, the mold clamping device (not shown) is operated to move the movable platen 31 to the stationary platen 11 side, and the movable platen plate 36 and the stationary platen plate 16 are brought into contact with each other to carry out the molding. The recess 50 is closed by the fixed side disc plate 16 to form a cavity space.

In the spooling holder 44, a spooling retainer 51 formed integrally with the cut punch 48 is provided, and a cut punch return spring (in the right side in the drawing) in front of the spooling retainer 51 ( 52 is provided, and the cut punch return spring 52 elastically supports the cut punch 48 rearward (left in the drawing). In addition, the rod 61 is freely moved forward and backward by contacting the rear end of the cut punch 48.

The movable side assembly 32 is also provided with an ejector bush, an ejector pin, an movable side air blow bush and the like which are not shown.

In the disk forming apparatus of the above configuration, the mold clamping apparatus can be operated to move the movable side assembly 32 forward (move to the right in the drawing) to perform mold closing, and the movable side assembly 32 is fixed. The mold can be pressed by the platen 11, and the mold can be opened by moving the movable assembly 32 back to the left in the drawing.

When the cut punch 48 is advanced by a predetermined extrusion force and enters the die 28 at a predetermined timing while the mold is being formed, the spool 26 and the cavity space are blocked by the cut punch 48. The gate cut is performed. Further, punching is applied to a molded substrate (not shown) molded in the cavity space to remove the inner diameter.

For this purpose, a gate cut device is installed.

2 is a conceptual diagram of a gate cut device in an embodiment of the present invention.

In the figure, 12 is a fixed side assembly, 32 is a movable side assembly, 48 is a cut punch, 62 is a gate cut cylinder as a driving part, and the gate cut cylinder 62 is freely provided in the cylinder body 63 and the cylinder body 63. It consists of a piston 64 installed to slide. In addition, the piston 64 is composed of a head 67 and a rod 61 formed extending from the head 67 to the front (right side in Fig. 2). Therefore, the cut punch 48 can be moved back and forth (moving in the left and right directions in the drawing) by driving the gate cut cylinder 62.

To this end, the cylinder body 63 is partitioned by the piston 64, a first oil chamber 65 on the head 67 side, and a second oil chamber 66 on the rod 61 side. Is formed. The gate cut cylinder 62 is connected to the solenoid valve 71 via lines L1 and L2, and the solenoid valve 71 is connected to the accumulator 72 through the line L3 and the oil tank 73 through the line L4. ), Respectively. The solenoid valve 71 receives the command signal from the control device 81 in the solenoid (a) and (b), is switched, and adopts positions A, B, and N. L4 is connected, and the position B is connected between lines L1 and L4 and between lines L2 and L3. Further, the gate cut device is constituted by the fixed side assembly 12, the movable side assembly 32, the cut punch 48, the gate cut cylinder 62, the solenoid valve 71, and the control device 81. .

Therefore, when the solenoid a is excited and the solenoid valve 71 is positioned at position A, oil in the accumulator 72 is supplied to the first oil chamber 65 to advance the rod 61 (Fig. To the right of). As a result, the cut punch 48 is advanced. On the other hand, when the solenoid b is excited and the solenoid valve 71 is placed in position B, oil in the accumulator 72 is supplied to the second oil chamber 66 to retract the rod 61 (left side in the drawing). Move to As a result, the cut punch 48 is retracted.

When the solenoids a and b are not both excited, that is, the solenoid valve 71 is placed at the position N, the lines L1, L2 and the line L4 are connected to each other so that the first oil chamber 65 and the second oil chamber ( The oil in 66 is discharged to the oil tank 73 through the throttles 74 and 75 formed in the solenoid valve 71. In this case, the solenoid valve 71 becomes neutral, and the extrusion force and the return force by the cut punch 48 do not generate | occur | produce.

By the way, although resin is filled in the cavity space which is not shown in the state which carried out shaping | molding, when the said gate cut device is driven and the cut punch 48 protrudes before resin in a cavity space is solidified, extrusion force is maintained. The movable side assembly 32 is to be retracted.

In this case, since the extrusion force is maintained when mold opening is performed, the movable shaft assembly 32 cannot be retracted at the timing, speed, or the like as set, and mold release unevenness may occur on a disk (not shown), resulting in mold failure. .

Therefore, the drive part control means (not shown) of the control apparatus 81 makes the extrusion force of the cut punch 48 smaller than a set value, for example, before making a mold opening. To this end, the drive unit control means stops the excitation of the solenoid (a), puts the solenoid valve 71 in position N, and discharges the oil in the first oil chamber 65 and the second oil chamber 66 to the oil tank 73. do. As a result, the cut punch 48 is placed in the advanced position but the extrusion force of the cut punch 48 becomes zero.

Subsequently, when the mold opening is performed, the cut punch 48 is placed at the advanced position so that the disk does not fall from the cavity space. Subsequently, when the disk is taken out, the control device 81 excites the solenoid b, sets the solenoid valve 71 at the position B, and supplies oil to the second oil chamber 66. As a result, the cut punch 48 is retracted.

Since the extrusion force of the cut punch 48 becomes smaller than the set value before the mold opening is performed in this manner, the movable side assembly 32 does not retreat while the extrusion force is maintained. Therefore, since the movable side assembly 32 can be retracted at the set timing, speed, etc., mold release irregularity does not arise in a disk according to mold opening, and molding defect can be prevented from occurring.

In the present embodiment, the gate cut cylinder 62 is used as the driving unit for driving the gate cut device, but an electric motor may be used instead of the gate cut cylinder 62.

In that case, a gatecut motor is used as the electric motor so that the drive control means reduces or stops the supply of current to the gatecut motor before the mold opening is performed.

In addition, this invention is not limited to the said embodiment, It can change variously based on the meaning of this invention, and does not exclude them from the scope of this invention.

As described in detail above, when the present invention is used, since the extrusion force of the cut punch becomes smaller than the set value before the mold opening is carried out, molding failure such as mold release stain at the start of mold, which is caused when the movable mold is retracted while the extrusion force is maintained, is maintained. Can be prevented.

Claims (4)

A movable mold which forms a cavity space between the stationary mold and the stationary mold with the stationary mold freely installed and faced to face the stationary mold, and is installed facing the cavity space, and the cut punch enters the end. A spool having a concave portion, a cut punch provided freely forward and backward with the concave portion facing the concave portion, a drive portion driven to move forward and backward through the cut punch, and a shape driven by driving the drive portion; And a drive section control means for advancing the cut punch by a predetermined extrusion force to perform gate cut, and for reducing the extrusion force of the cut punch to be smaller than a set value before the mold opening is performed. 2. The gate cut device of the disk forming apparatus as claimed in claim 1, wherein the drive unit is a gate cut cylinder, and the drive unit control means extracts oil from the oil chamber of the gate cut cylinder before the mold opening is performed. 2. The gate cut device of the disk forming apparatus as claimed in claim 1, wherein the drive section is a gate cut motor, and the drive section control means reduces or stops the supply of current to the gate cut motor before the mold opening is performed. . Pressing the movable mold into the stationary mold to perform the mold cutting, and proceeds to the gate cut by advancing the cut punch installed facing the cavity space while the mold is being made, and reducing the extrusion force of the cut punch below the set value, and performing mold opening. The gate cut method of the disk forming apparatus.