JPH05200770A - Injection molding system - Google Patents

Abstract

PURPOSE:To enable a movement and clamping of a nozzle and mold wherein a face mold part can be driven at high freedom, a vacuum can be drawn in a short time and when a molding material is cured prior to casting into the mold, restoration to an original state can be performed in a short time under a state wherein mold deformation is hard to generate by a reduction or elimination of energy and approcach to the mold can be performed from an arbitrary direction. CONSTITUTION:A stationary mold part of a mold which is constituted of the stationary mold part 1, movable mold part 2 and side face mold part 3 possesses a recessed part 31 capable of holding a plurality of nozzles and in a driving mechanism 5 of a moving power system and a pressurizing mechanism 8 of a mold clamping power system moving and integrating the mold are incorporated into the same mold part. A sealing material is arranged on the circumference of a mold surface of a cavity 4 side where those molds are joined to each other, those molds are fitted to an injection molding machine 6 which does not have a tie bar and the title injection molding system is constituted of the injection molding machine 6 and an injection molding machine whose tip of a main nozzle 27 possesses a branch part 28 and a plurality of the nozzles 29.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an injection molding system including an injection molding machine, a mold and the like.

[0002]

2. Description of the Related Art In conventional injection molding, a molded product having an external thread or a molded product having an undercut on the outside uses a mold having a split mold or a mold having a slide core partially formed. There is a way. There is a method of using a cold runner for the mold for resource saving and effective use of the molding material. In order to prevent low-pressure molding, short-time molding, defective filling of molded products, excessive flash (flash) defects, dimensional defects, etc., there is a method of using an air vent to evacuate the mold. There are technologies such as the use of auxiliary rams in direct pressure type and the use of toggle type mold clamping mechanism for energy saving of mold movement and mold clamping power. Plastic books 257-259 respectively
Pp. 210 to 211, published on May 10, 1978, Plastic Age Co., Ltd. and Japanese Patent Publication No. 53-141642. There is also an injection molding system that combines these.

However, in these systems, in the case of the slide core structure, the side mold part which is the slide core is incorporated in either the movable mold part or the fixed mold part, so that there is a limitation in movement. , There was a problem that they could not be integrated from any direction.

Further, both the use of a direct pressure type auxiliary ram for energy saving and an injection molding machine having a toggle type mold clamping mechanism become complicated as a machine, and particularly the toggle type is highly designed and manufactured. Skill and precision were required, and there was a problem that wear and breakage were likely to occur.

With respect to the mold clamping mechanism of this injection molding apparatus, in both the direct pressure type and the toggle type, the molds attached to the movable plate and the fixed plate are the molds with four pillars called tie bars as tracks. Moved and clamped. Therefore, a large amount of power is required for movement and mold clamping. This large mold clamping force easily causes distortion in the mold, which causes a problem of forming flash. Furthermore, when inserting insert inserts or taking out runner-less inserts that require a large number of grips to grip individual inserts, the tie bar interferes with insert inserts and runner insertion. When taking out the molded product without the press, the mold cannot be approached from any direction, and the direction of taking out and the size of the insert product or the molded product are limited. Therefore, this affects the number of molds to be taken, the mold layout, and the design of the molded product.

Further, when the molding material is hardened in the cold runner portion, it is necessary to first remove the fixed die from the injection molding machine, and further disassemble the manifold portion having the cold runner portion from the fixed die. , It takes a lot of time and effort to restore it. Further, since the temperature distribution of the cold runner portion is large, the molding material is easily hardened, and stable continuous molding is difficult.

Molding of a molded product using a mold reduces the molding pressure depending on how quickly and completely the heat-plasticized molding material replaces the air in the cavity of the mold.
Occurrence of shortening of molding time, defective filling of molded products, excessive flash (flash), dimensional defects, etc. are affected. The method of using an air venge or the vacuum drawing in the mold using a knockout pin which is often used as another method has a problem that the vacuum cannot be made in a short time.

[0008]

DISCLOSURE OF THE INVENTION According to the present invention, a side mold part necessary for obtaining a molded product having an outer screw or a molded product having an undercut on the outside can be driven with a high degree of freedom, and the mold can be moved. , Mold clamping can be done with energy saving, mold distortion is less likely to occur, and the mold can be approached from any direction and vacuum drawing can be done for a short time. If the mold and the molding material harden before being injected into the mold, An object of the present invention is to provide an injection molding system including a nozzle of an injection molding machine and a mold that can be restored in a short time.

[0009]

The present invention has been made in view of the above points, and is characterized by a fixed mold part, a movable mold part facing the fixed mold part, and these molds. The fixed mold part of the mold, which is composed of the side mold part that moves from the side surface and becomes integral, has a concave part in which the nozzle can be housed in the mold, and the movable mold part and the side mold part. A drive mechanism of a moving power system for moving and integrating the mold and a pressurizing mechanism of a mold clamping power system for the mold are incorporated in the same mold part as separate mechanisms, and these molds are joined to each other. A sealing material is arranged around the surface of the mold on the cavity side, and these molds are attached to an injection molding machine that does not have a tie bar, and a branch portion and a plurality of nozzles are provided at the tip of the main nozzle of this injection molding machine. It is in an injection molding system consisting of an injection molding machine.

[0010]

In the injection molding die including the fixed die portion, the movable die portion, and the side die portion that is integrally formed by moving from the side surface, the movable die and the side die portion are moved and clamped respectively. Since the mold drive mechanism and the pressurizing mechanism are installed separately in the injection molding machine, the movement of the side mold part is independently controlled regardless of the movement of other mold parts with a high degree of freedom. it can. Therefore, it is possible to select the most suitable direction for the movement of the side surface mold part according to the shape of the molded product.

Since the same mechanism is used, it is not necessary to move and clamp the mold by the tie bar, the mold can be approached from any direction, and insert molding insert products and runnerless molded product removal can be performed at any time. You can do it from anywhere.

Further, since the individual mold parts are moved by the individual drive mechanisms mounted on the base of the injection molding machine, a small moving power is sufficient. Clamping of the integrated mold can be performed after the integration by operating a pressure mechanism that is a mold clamping power system attached to the movable mold part and the side mold part. In a situation where the mold clamping is balanced in the interior surrounded by the mounting plate of each mold part, the mold clamping pressure can be generated with a short stroke movement. Can be tightened. For this reason, distortion is unlikely to occur in the mold, and no gap is formed on the parting surface of the mold, so that the occurrence of burrs can be prevented. In the case of long-term use, this difference in flash generation becomes noticeable.

The branch portion at the tip of the main nozzle and the plurality of nozzles, which are disposed in the concave portion engraved in the fixed mold portion without contacting the mold, directly contact the gate of the mold when the molding material is injected. Being used. The branch part and the plurality of nozzles have a structure that is easy to insulate and separate from the mold, so that the heat insulating effect is improved, and the branch part and the plurality of nozzles remain at about the same temperature as the main nozzle. Therefore, curing is less likely to occur in the branch portion and the plurality of nozzles, stable injection molding can be performed one after another, and the molding material can be effectively used. Also,
The disassembly time can be shortened because the branch part and multiple nozzles can be removed without removing the mold.

A mold comprising a fixed mold part, a movable mold part facing the fixed mold part, and a side mold part which is movable to the mold parts from the side surface to be integrated, is preferably integrated. After mechanically connecting each other and before clamping, the dies are slightly opened, preferably by about 0.1 to 2 mm, and the dies are sealed with each other to draw a vacuum, so that the air flow path is large when evacuating. .. Therefore, evacuation can be completed in a short time. After that, when the mold clamping is completed, the inside of the cavity of the mold is in a vacuum state, so that the heat-plasticized molding material enters into the cavity of the molding mold. Therefore, low-pressure molding and injection of the molding material can be performed for a short time, and the molding material completely fills the cavity, so that defective filling, excessive flash, defective dimensions, etc. are eliminated.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings. The present invention is not limited to these examples.

FIG. 1 is a side view showing a mold open state of a mold of an injection molding system of the present invention. The injection molding die includes a fixed die portion 1, a movable die portion 2 arranged so as to face the fixed die portion, and two side surface die portions 3 which are integrated with each other by moving from the side surface to these die portions. 3 and 3. The movable mold part 2 arranged so as to face the fixed mold part 1 is attached to a drive mechanism (not shown) which is a moving power system.
Side molds 3 and 3 arranged one by one on the left and right are attached to a drive mechanism 5 which is a moving power system. The drive mechanism 5 and the fixed mold part 1 are arranged on the same base 7 of the injection molding machine 6.

The side molds 3 and 3 rotate 90 ° in the direction of the arrow when the mold is clamped, and the inner walls of the cavities 4 are directed inward toward each other by the moving power system of the actuator 9 and the rod-shaped screw 10 of the drive mechanism 5. The two move forward toward the center of each other, and the movable mold part 2 is also lowered by a similar drive mechanism (not shown) to be combined and integrated. FIG. 2 is a side view showing the state before the mold clamping after the integration.

After the integration, before the completion of the mold clamping, air gaps of air passages can be secured between the dies so that there is an air passage 23 having a gap of preferably about 0.1 to 2 mm. Sealing is provided at the peripheral portion of the die, for example, an O-ring, a flexible packing material or a die part mechanism incorporated by being projected in a convex shape by a spring, and the like. The vacuum device 24 provided outside the tube 2
Tie at 5 and evacuate. After that, the mold is completely clamped, and the heat-plasticized molding material is used for the cavity 4 of the molding mold.
A molded article can be obtained by injecting into the inside.

Examples of the heat-plasticized molding material include thermosetting resin moldings composed of phenol resin, unsaturated polyester resin, epoxy resin, melamine resin, urea resin, polyimide resin, etc. The material can be appropriately selected and used.

FIG. 3 is a front view and FIG. 4 is a side view of a drive mechanism of a moving power system for moving the movable mold part 2 and the side mold part 3. The driving mechanism 5 of the moving power system is an actuator 9 and a rod-shaped screw 10, and the mold part moves along the rail 10a as a track. Other units such as a hydraulic cylinder unit and an air cylinder unit can be used. Above all, the motor and the rod-shaped screw are preferable in that the positional accuracy can be obtained quickly and the cleanliness of the device is maintained.

After combining and integrating the respective mold parts, it is possible to prevent the molds from opening each other even when the next mold clamping force is applied by the mechanical coupling mechanism.
5 and 6 are a front view and a side view of the model case with and without mechanical connection. Since FIG. 5 has the same structure on the left and right, the right part will be described. Cylindrical protrusions 12 are fixedly arranged near the upper and lower ends of the mounting plate 11 of the side surface mold part pressing mechanism 8.
Separately, there is a cutout portion 14 of approximately 1/4 circle in the vicinity of the left and right end portions of the plate 13 to which the pressing mechanism 8 of the movable mold portion is attached,
A cylindrical protrusion 15 is provided which is rotatable about its center. These two columnar protrusions are arranged so as to form concentric circles when the mold parts are combined and integrated. Mounting plate 13 having this cylindrical protrusion 15
The cylindrical protrusion 1 which can be rotated by a gear or disc 17 for transmitting the rotation of the actuator 16 attached to the
It is possible to rotate 5 by 180 degrees to mechanically connect or disconnect. The X state between the movable mold part 2 and the side surface mold part 3 is a mechanically coupled state, and the Y state between the fixed mold part 1 and the side surface mold part 3 is mechanical by using the same mechanism. It is in a state where they are not physically connected. When the side mold part 3 is moved to the right and the mold is opened, in the X state, the columnar protrusion 12 cannot be opened because the rotatable columnar protrusion 15 is hindered by a higher portion which is not a notch. . In the Y state, when the side surface mold part 3 is moved to the right, the cylindrical protrusion 1
2 is a cutout portion 1 of a rotatable columnar protrusion 15.
Since it is located at 4, you can move it and open the mold.

As the pressurizing mechanism 8 of the mold clamping power system, in addition to the hydraulic unit 8a composed of the hydraulic cylinder 18, a unit composed of an air cylinder, a motor and a rod screw can be used. An embodiment in the case of the hydraulic cylinder 18 is shown in FIG. 7 in an enlarged cross-sectional view of a portion A surrounded by the polishing type in FIG. A hydraulic unit 8a is arranged on a mounting plate 13 of a pressurizing mechanism 8 mounted on the lower end of a drive mechanism (not shown) for moving the movable mold part 2. The ram 21 is moved up and down by adjusting the amount of oil injected from the upper port 19 or the lower port 20 of the hydraulic cylinder 18 of the hydraulic unit 8a. The mold is clamped apart from the pressure mechanism 8 mounting plate 13 of the mold. FIG. 7 shows a case where the amount of oil from the upper port 19 is increased and a little pressure is applied for mold clamping.

FIG. 8 is a front view of a plurality of nozzles and a branch portion of the injection molding machine. A main nozzle 27 is provided at the tip of a cylinder 26 of the injection molding machine, and a branching portion 28 is provided further ahead.
And two nozzles 29, 29 are attached. From the main nozzle 27 to the plurality of nozzles 29, 29, from the tip of the main nozzle 27, the plurality of nozzles 29, 2
A branch portion 28 for branching the heat-plasticized molding material is provided between the two. Flow path 3 of this branch portion 28
The shape of 0 is not particularly limited such that the cross-sectional shape is circular, elliptical, semicircular, and the nozzle 29 far from the main nozzle 27.
The diameter of the flow path 30 reaching the nozzle 2 is increased.
It is preferable to give consideration to the uniform flow of the molding material without generating heat as much as possible, for example, by forming a gradient in the flow path 30 on the way to 9. A plurality of nozzles 29 can be appropriately adopted depending on the number of molded products and the size.

The fixed mold part 1 is provided with a rectangular recess 31 (shown in FIG. 1) into which the plurality of nozzles 29 can be inserted without contacting the mold. Further, the shape of the concave portion 31 may be a cylindrical shape having a diameter slightly larger than that of each nozzle matched with each nozzle.

[0025]

As described above, according to the present invention, it is possible to drive the side surface mold portion necessary for obtaining a molded product having an outer screw or a molded product having an undercut on the outside with a high degree of freedom. Further, the mold can be evacuated in a short time, and when the molding material is cured before being injected into the mold, it is performed in a short time to restore the original structure due to the structural relationship between the nozzle of the injection molding machine and the mold. be able to. In addition, the movement of the mold that saves energy and is less likely to cause distortion in the mold,
You can clamp the mold. Also, the mold can be approached from any direction,
Insert molding inserts can be inserted and runner-less moldings can be taken out from any position.

[Brief description of drawings]

FIG. 1 is a side view showing a mold opening state of a mold in an injection molding system of the present invention.

FIG. 2 is a side view showing a vacuum drawing state of a mold in the injection molding system of the present invention.

FIG. 3 is a front view showing a mold driving mechanism of the injection molding system of the present invention.

FIG. 4 is a side view of FIG.

FIG. 5 is a front view showing mechanical coupling of molds of the injection molding system of the present invention.

FIG. 6 is a side view of FIG.

FIG. 7 is a cross-sectional view showing a pressurizing mechanism of section A of FIG.

FIG. 8 is a front view showing a branch portion and a nozzle of the injection molding system of the present invention.

[Explanation of symbols]

 1 Fixed mold part 2 Movable mold part 3 Side mold part 4 Cavity 5 Drive mechanism 6 Injection molding machine 7 Base 8 Pressurizing mechanism 8a Hydraulic unit 9 Actuator 10 Rod screw 10a Rail 11 Mounting plate 12 Cylindrical protrusion 13 Mounting plate 14 Notch Part 15 Cylindrical Protrusion with Notch Part 16 Actuator 17 Gear 18 Cylinder 19 Upper Port 20 Lower Port 21 Ram 22 Movable Mold Mounting Plate 23 Air Flow 24 Vacuum Device 25 Pressure Tube 26 Cylinder 27 Main Nozzle 28 Branch Part 29 Nozzle 30 Channel 31 Recess

Claims (1)

[Claims] 1. A fixed mold for a mold comprising a fixed mold part, a movable mold part facing the fixed mold part, and a side mold part which is integrated with the mold part by moving from a side surface. The part has a recess for accommodating a nozzle, and the movable mold part and the side mold part are provided with a moving power system drive mechanism for moving and integrating the mold and a mold clamping power system. A pressure mechanism is installed as a separate mechanism in the same mold part, and a sealing material is arranged around the mold surface on the cavity side where these molds are joined together, and these molds do not have tie bars. An injection molding system that is an injection molding machine that is attached to a molding machine and has a branch portion and a plurality of nozzles at the tip of the main nozzle of the injection molding machine.