JPH0740029A - Insert holder of metal mold for molding - Google Patents

Abstract

PURPOSE:To surely hold inserts which are inserted into metal molds for molding and are simultaneously molded in such a manner that these insert do not move and are not dislodged from fitting parts during injection molding. CONSTITUTION:This insert holder of the metal molds for molding has an outer pin 31 and inner pin 35 as magnetic materials of a central part which are inserted with the outer insert 32 and the inner insert 36 and are in contact with each other and an outer bobbin 29 and inner bobbin 33 as nonmagnetic materials around these magnetic materials in the moving mold 7 which is held with the outer insert 32 and inner insert 36 in the front end facing the inside of a cavity 16 of the metal molds. Electromagnetic coils 30, 34 are wound around the outer peripheral parts of the nonmagnetic materials.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a die casting machine, a plastic injection molding machine or the like, in which an insert which is inserted into a molding die and simultaneously molded moves during injection molding or falls off from a fitting portion. The present invention relates to an insert holding device for a molding die that holds the insert so that it does not come loose.

[0002]

2. Description of the Related Art In injection molding using a die casting machine, a plastic injection molding machine or the like, a molten metal or a molten resin is injected into the cavity of a mold and solidified to obtain an injection molded product. By the way, in this type of injection molding, for example, an insert for a bearing formed in a ring shape or a semi-circular arc shape is fitted on a movable convex portion or a core pin facing the inside of the cavity of the mold. Often, simultaneous molding with injection molded products is performed.

However, in injection molding in which such inserts are inserted and simultaneously molded, the inserts may move due to the vibration of the machine during mold clamping or the flow of the melt injected into the cavity during molding, or the inserts may move. Sometimes dropped into the cavity, resulting in defective molded products, which was an obstacle to automation and rationalization. In addition, there is a case in which a pressing pin that presses the insert is arranged in order to prevent the pressing pin from falling into the cavity, but in this case, there is a problem that the pressing pin mark remains as a hole in the product.

Therefore, for example, Japanese Patent Laid-Open No. 62-229225
As disclosed in Japanese Unexamined Patent Publication (Kokai) No. 0-242, a core pin in which an insert is mounted at a tip end facing the inside of a cavity of a mold is provided When the electromagnetic coil is fitted to the outer periphery of the non-magnetic material, and the insert is fitted to the core pin to energize the electromagnetic coil, the magnetic material and the insert of the core pin are magnetized and the insert is inserted. Is firmly attached to the core pin, and even if the machine vibrates or the injection melt flows in the cavity, the insert moves or falls without the need for a holding pin. There are things that prevent you from doing it.

[0005]

By the way, in this case, since the portion holding the insert is formed of a non-magnetic material, it is easily deformed by heat during casting, and the insert cannot be held accurately. There is.

Further, the magnetic bypass pin is inserted into the non-magnetic material, the magnetic material of the core pin and the insert are magnetized by the magnetic bypass pin, and the insert is adsorbed, so that the magnetic bypass pin is incorporated into the non-magnetic material. In addition, the accuracy of the holes of the non-magnetic material is required, which increases the manufacturing cost.

Further, at the time of casting, since the non-magnetic material and the magnetic bypass pin have different coefficients of thermal expansion, the deformation amounts are different, and a gap is created between the magnetic bypass pin and the magnetic material or the insert. The and may not be magnetized and may not be able to hold the insert accurately.

The present invention has been made in view of the above points, and ensures that the inserts inserted into the molding die and simultaneously molded do not move or fall off during the injection molding. An object of the present invention is to provide an insert holding device for a holding mold.

[0009]

In order to solve the above-mentioned problems, the invention according to claim 1 inserts the insert into a movable mold in which the insert is held at the tip end facing the inside of the cavity of the mold. It is characterized in that it comprises a magnetic material in the central portion in contact with the magnetic material and a non-magnetic material around the magnetic material, and an electromagnetic coil is wound around the outer peripheral portion of the non-magnetic material.

[0010]

According to the first aspect of the present invention, since the insert is directly held by the magnetic material during casting, the magnetic material and the insert are magnetized, whereby the insert can be firmly held.

Further, since the portion holding the insert is made of a magnetic material, it is hard to be deformed by heat during casting,
The insert can be held accurately.

Further, since the portion for holding the insert is directly made of a magnetic material, the conventional magnetic bypass pin is not required, the manufacturing is easy, and the manufacturing cost is reduced.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an insert holding device for a molding die of the present invention will be described in detail below with reference to the drawings. Figure 1
3 to 3 show an example in which the insert holding device for a molding die according to the present invention is applied to a horizontal die clamping horizontal casting die casting machine, and FIG. 1 is a cross-sectional view of the die casting machine with the die opened, 2 is a sectional view of the die casting machine in a closed state, and FIG. 3 is an enlarged sectional view of the die casting machine in a closed state.

A fixed platen 3 is erected on a machine base 2 of the die casting machine 1, and the fixed platen 3 and a link housing (not shown) are connected by, for example, four tie bars 4. The movable platen 5 is supported by the tie bar 4, and the movable platen 5 moves forward and backward with respect to the fixed platen 3 by a mold clamping cylinder on the link housing side.

The fixed platen 3 is provided with a fixed die 6,
A movable die 7 is provided on the movable platen 5 via a die base 8. The fixed die 6 and the movable die 7 are connected by, for example, four guide pins 9, and an intermediate die 10 is movably provided on the guide pins 9.

The intermediate mold 10 is provided with a fixed insert 11 in the concave hole, and the movable mold 7 is provided with a movable insert 12. A recess 13 is formed in the fixed insert 11, and a core 15 is provided in the recess 14 of the movable insert 12. The recess 13 of the fixed insert 11 and the movable insert 12 are provided in the mold clamping state shown in FIG. A cavity 16 is formed between the recess 14 and the core 15.

A sprue 17 is provided in the center of the intermediate die 10 and the fixed insert 11 so as to communicate with the recess 13, and a groove 18 is formed in the fixed die 6, so that in the mold clamping state shown in FIG. By joining the intermediate die 10 and the fixed die 6, the groove 18 forms a hot water passage 19 communicating with the sprue portion 17.

A cylindrical fixed sleeve 20 is inserted in the fixed mold 6 so as to communicate with the groove 18, and a cylindrical injection sleeve 21 is inserted in the fixed platen 3. A pouring port 22 is formed in the injection sleeve 21, the injection sleeve 21 is fitted on the same axis as the fixed sleeve 20, and a blanker chip 23 of an injection cylinder (not shown) is reciprocally movable in its inner hole. It is fitted.

Therefore, when the molten metal is supplied from the pouring port 22 and the plunger tip 23 is moved forward, the molten metal is ejected from the injection sleeve 21 into the cavity 16 through the fixed sleeve 20, the melt passage 19, and the spout portion 17, and is solidified. Then, a cast product as an injection molded product is obtained.

On the other hand, the pin hole 24 provided in the movable platen 5
The support plate 2 is moved forward and backward by an extrusion cylinder (not shown).
An extruding rod 26 integral with 5 is pierced, and an extruding plate 28 having a plurality of extruding pins 27 is fixed to the tip of the extruding rod 26. And the push pin 27
Has reached the intermediate mold 10 through the movable mold 7 and the movable insert 12, and the movable platen 5 is retracted to open the mold as shown in FIG. 1, and then the extrusion pin 27 is advanced by the extrusion cylinder. , Cavity 1 by pressing the intermediate mold 10
The casting in 6 is taken out.

In the die casting machine 1, an insert that is molded at the same time as the molded product is inserted into the cavity 16. That is, the outer bobbin 29 as a non-magnetic material is inserted into the recess 14 of the movable insert 12 of the movable die 7,
An electromagnetic coil 30, which is connected to a power source (not shown) by a lead wire, is wound inside an annular groove 29a provided on the outer peripheral portion of the outer bobbin 29.

An outer pin 31 as a magnetic material is inserted into the outer bobbin 29 from the side of the intermediate die 10, and a flange portion 31a of the outer pin 31 forms a predetermined gap for forming the cavity 16 with the recess 14 of the movable insert 12. Have and face each other. The outer insert 32 is inserted into the flange portion 31a of the outer pin 31 so as to come into contact with the outer pin 31 as a magnetic material in the central portion.

An inner bobbin 33 as a non-magnetic material is inserted into the outer pin 31 from the movable platen 5 side, and an annular groove 33a provided on the outer peripheral portion of the inner bobbin 33 leads to a power source (not shown). Electromagnetic coil 3 connected by wire
4 is wound. An inner pin 35 as a magnetic material is inserted into the inner bobbin 33 from the movable platen 5 side, and a tip end portion 35a of the inner pin 35 has a predetermined gap for forming a cavity 16 with a flange portion 31a of the outer pin 31. Are facing each other. An inner insert 36 is attached to the tip portion 35a of the inner pin 35 so as to come into contact with the inner pin 35 as a magnetic material at the center. A plate 37 as a non-magnetic material is provided on the head portion 35b of the inner pin 35.

An air passage 38 communicating with the electromagnetic coil 30 and the electromagnetic coil 34 is formed in the movable die 7, and a hose 39 is connected to an opening of the air passage 38.
An air source (not shown) is supplied to the hose 39, and this air is sent to the electromagnetic coil 30 and the electromagnetic coil 34 through the air passage 38 to cool the electromagnetic coil 30 and the electromagnetic coil 34.

Therefore, by energizing the electromagnetic coil 30, a magnetic flux is formed, and this magnetic flux is transmitted between the outer pin 31, the outer insert 32, and the movable nest 12 to form a closed magnetic field, and the outer insert 32 is placed outside. It is configured to be attracted to the pin 31. A magnetic flux is formed by energizing the electromagnetic coil 34, and this magnetic flux is transmitted between the inner pin 35, the inner insert 36, and the outer pin 31 to form a closed magnetic field, and the inner insert 36 is attached to the inner pin 35. It is configured to be adsorbed.

When an alternating current is applied to the electromagnetic coil 30 and the electromagnetic coil 34 and a magnetic flux is formed in the direction of arrow A by energizing the electromagnetic coil 30, the electromagnetic coil 34
When a magnetic flux is formed in the arrow A direction by energizing the electromagnetic coil, and a magnetic flux is formed in the arrow B direction by energizing the electromagnetic coil 30, a magnetic flux is formed in the arrow B direction by energizing the electromagnetic coil 34. , A plurality of electromagnetic coils are provided so as not to cancel magnetic forces from each other.

By providing the plate 37 as a non-magnetic material from the head portion 35b of the inner pin 35 to the head portion 31b of the outer pin 31, the magnetic field generated by the electromagnetic coils 30 and 34 escapes from the movable nest 12 to the outside. The magnetic force is prevented from weakening.

Further, the portion holding the outer insert 32 and the inner insert 36 is formed of the magnetic material of the outer pin 31 and the inner pin 35, which eliminates the need for the conventional magnetic bypass pin and facilitates the manufacture. Moreover, the manufacturing cost is reduced.

Outer insert 32 and inner insert 3
Since the portion holding 6 is formed of the magnetic material of the outer pin 31 and the inner pin 35, it is hard to be deformed by heat during casting, and the outer insert 32 and the inner insert 36 can be firmly held.

Furthermore, the fixed die 6, the movable die 7 and the intermediate die 1
A cavity 16 is formed at 0, and a sprue 17 is set at the center of the product formed by the cavity 16.
As a result, the inner insert 36 located at the center is pressed by the flow of the molten metal, so that the inner insert 36 can be reliably held even with a small magnetic force during casting. Similarly, since the sprue part 17 is set in the center of the product in the outer insert 32, the spout is evenly pressed by the flow of the molten metal, so that the inner insert 36 can be reliably held even by a minute magnetic force during casting. it can.

The injection operation of the die casting machine 1 configured as above will be described. As shown in FIG. 1, with the movable platen 5 retracted, the outer insert 32 is inserted into the flange portion 31a of the outer pin 31 and the inner insert 36 is inserted into the tip portion 35a of the inner pin 35. . A magnetic flux is formed by energizing the electromagnetic coil 30, and the magnetic flux is transmitted between the outer pin 31, the outer insert 32, and the movable nest 12 to form a closed magnetic field. It is strongly adsorbed. A magnetic flux is formed by energizing the electromagnetic coil 34, and this magnetic flux is transmitted between the inner pin 35, the inner insert 36, and the outer pin 31 to form a closed magnetic field, and the inner insert 36 is attached to the inner pin 35. It is strongly adsorbed.

In this state, when the movable platen 5 is moved forward, the mold is clamped as shown in FIG. 2, and the recesses 14 and the core 15 of the movable insert 12 of the movable mold 7 and the fixed insert 11 of the intermediate mold 10 are carried out. Since the cavity 16 is formed between the molten metal from the pouring port 22 of the injection sleep 21 and the plunger tip 23 is moved forward, the molten metal flows from the injection sleeve 21 to the fixed sleeve 20 and the runway 1.
9. It is injected into the cavity 16 through the sprue part 17.

When the movable platen 5 is retracted after waiting for the molten metal in the cavity 16 to be solidified and cooled, the movable mold 7 and the intermediate mold 10 are retracted to open the mold, as shown in FIG. After opening the mold, push pin 2 with the push cylinder.
By moving 7 forward, the intermediate die 10 is pushed and the casting in the cavity 16 is taken out.

In such an injection operation, the machine vibrates before and during the injection of the molten metal, the fixed mold 6, the movable mold 7, and the intermediate mold 10 vibrate, and the outer insert 32 and the inner insert 36 move. The outer insert 32 is adsorbed by the outer pin 31 and the inner insert 36 is adsorbed by the inner pin 35 and firmly held by the outer pin 31. The pin 35 is prevented from moving and falling off.

Although this embodiment shows an example in which the present invention is applied to the horizontal mold clamping die of the die casting machine, it can also be applied to the vertical mold clamping die in the same manner, and the plastic injection molding is also possible. The same can be applied to the mold of the machine.

[0036]

As is apparent from the above description, the magnetic material at the central portion where the insert is inserted and in contact with the movable die in which the insert is held at the tip end facing the cavity of the die, and the magnetic material. Since the non-magnetic material around the non-magnetic material is provided and the electromagnetic coil is wound around the outer peripheral portion of the non-magnetic material, the insert is directly held by the magnetic material, whereby the magnetic material and the insert are magnetized to strengthen the insert. Can be held.

Further, since the portion holding the insert is made of a magnetic material, it is hard to be deformed by heat during casting,
The insert can be held accurately.

Further, since the portion for holding the insert is directly formed of a magnetic material, the conventional magnetic bypass pin is not required, the manufacturing is easy, and the manufacturing cost is reduced.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a die casting machine with a mold opened.

FIG. 2 is a cross-sectional view of a die casting machine in a state where a mold is closed.

FIG. 3 is an enlarged cross-sectional view of the die casting machine in a state where the mold is closed.

[Explanation of symbols]

 7 Movable 16 Cavity 29 Outer bobbin 30 Electromagnetic coil 31 Outer pin 32 Outer insert 33 Inner bobbin 34 Electromagnetic coil 35 Inner pin 36 Inner insert

Claims (1)

[Claims] 1. A magnetic material at a central portion, into which the insert is inserted and in contact, and a non-magnetic material around the magnetic material, in a movable die in which the insert is held at a tip end facing the inside of the cavity of the die. An insert holding device for a molding die, comprising an electromagnetic coil wound around an outer peripheral portion of the non-magnetic material.