KR20080112788A

KR20080112788A - Non-contact high-frequency induction resin injection apparatus for plastic mold

Info

Publication number: KR20080112788A
Application number: KR1020070061682A
Authority: KR
Inventors: 손유진
Original assignee: 손유진
Priority date: 2007-06-22
Filing date: 2007-06-22
Publication date: 2008-12-26

Abstract

A non-contact high frequency induction molten resin injection apparatus of multi-point gate type is provided to cope with changes in amount and position of injected resin according to the shape and structure of product. A non-contact high frequency induction molten resin injection apparatus of multi-point gate type comprises an inlet block(50) which is mounted on one end of a molten resin injection machine(30) in order to inject molten resin; a blow nozzle group(20) consisting of blow nozzles(20a,20b,20c) having different length and different runner size which are mounted on the lower side of the inlet block in order to inject the molten resin into a mold for injection-molding a product; first direct contact heating units(70a,70b, 70c) for heating up the tip end of each blow nozzle; and induction coil parts(22a,22b,22c) enclosing the back end of each blow nozzle in which Nozzle tips(21a,21b,21c) are formed.

Description

NON-CONTACT HIGH-FREQUENCY INDUCTION RESIN INJECTION APPARATUS FOR PLASTIC MOLD}

1 is a coupling state diagram of a non-contact high frequency induction molten resin injection apparatus of a multi-point gate method according to the invention.

FIG. 2 is an enlarged cross-sectional view of the multi-gate gate injection nozzle of FIG. 1.

3 is a control block diagram of a multi-point gate spray nozzle according to the present invention.

4 is a state diagram of the combined state of the non-contact high-frequency induction molten resin injection apparatus of the multi-point gate method according to another embodiment of the present invention.

* Explanation of symbols for the main parts of the drawings

100, 200: non-contact high frequency induction molten resin injection device of multi-point gate method

10: plastic injection mold 20, 20 ': injection nozzle group

20a, 20b, 20c, 20a ', 20b', 20c ': spray nozzle

21a, 21b, 21c, 21a ', 21b', 21c ': nozzle tip

22a, 22b, 22c, 22a ', 22b', 22c ': induction coil part

30: molten resin injection machine 40: manifold

41: manifold runner 42: heating device

50, 50 ': sprue

51a, 51b, 51c, 51a ', 51b', 51c ': inlet block runner

60a, 60b, 60c, 60a ', 60b', 60c ': injection nozzle runner

70a, 70b, 70c, 70a ', 70b', 70c ': first direct contact heating means

71a, 71b, 71c, 71a ', 71b', 71c ': second direct contact heating means

80: high frequency power supply unit 90: integrated controller

The present invention relates to a multi-point gate non-contact high frequency induction molten resin injection apparatus, and more particularly, a plurality of injection having a variety of sizes and lengths in a mold for manufacturing one small product, such as gears and small electronic products By applying an injection nozzle group consisting of nozzles, it is possible to meet the change in the amount or injection position of the molten resin injected according to the shape or structure of the product, as well as the non-contact high frequency formed on the tip side of the plurality of injection nozzles. The present invention relates to a non-contact high frequency induction molten resin injection apparatus of a multi-point gate system capable of integrating a common induction coil unit as a heating means.

In general, an injection mold for injection molding small products such as small electronic products or gears is composed of a movable side and a fixed side, and the movable side and the fixed side are configured to mold a product while mutually engaging and parting. The hot molten resin raw material for forming the product in the state where the side and the fixed side parts are joined to each other is run between the runner and the fixed core along the runner, and the supplied molten resin is molded into the product between the cores. In order to complete the product, the structure of the runner is a very important passage when molding the product in the injection mold.

On the other hand, according to the configuration of the manifold for supplying molten resin to the spray nozzle for opening and closing the gate of the conventional runner, a plurality of spray nozzles having runners are provided on the mold plate, and one of them is a runner for supplying molten resin to each of them. And install a manifold having a supply of the molten resin to the spray nozzle through the manifold.

In the conventional manifold structure having the above configuration, the rod heater or the buried type is disposed at a predetermined position of the manifold so that the molten resin material passing through the runner of the manifold for supplying the molten resin material can be smoothly supplied. The heating device of the direct contact type such as the cartridge heater and the like and the spray nozzle part are separately provided with the heating device such as the band heater.

However, the heating method by direct heating has a large amount of heat loss and the heating state is different according to the adhesion state, and it takes a relatively long time, and local heating is impossible. There was a problem in that it was not suitable for the heating of the divided area.

In addition, in the case of injection molding small products such as small electronic products and gears, in order to mold a single product, a plurality of injection nozzles having a multi-point gate method having various sizes and lengths are required. This multipoint gate method has not been proposed at all.

In addition, in the case of a multi-point gate method in which a plurality of spray nozzles are required in forming a single product, it is necessary to collectively control the heating devices of the respective spray nozzles. In the related art, each of these heating devices is integrated in one controller. There is no technology to control and share.

Accordingly, an object of the present invention has been made in view of the above problems, the injection nozzle consisting of a plurality of injection nozzles having various sizes and lengths in a mold for manufacturing one small product such as gears and small electronic products. By applying the group, it is to provide a non-contact high-frequency induction molten resin injection apparatus of a multi-point gate method that can be adapted to the change in the amount or injection position of the molten resin injected in accordance with the shape or structure of the product.

Another object of the present invention is to form an induction coil portion as a non-contact high frequency induction heating apparatus only on the outer periphery of the nozzle tip side of each injection nozzle, which is relatively far from the molten resin injector, where a large relative temperature drop occurs. The present invention provides a multi-point gate non-contact high frequency induction molten resin injection apparatus that can be commonly used for each induction coil unit by electrically connecting to an integrated control unit for controlling the coil unit integrally, thereby securing both technical and economical efficiency.

A multi-point gate high frequency induction molten resin injection apparatus according to the present invention for achieving the above object, in the molten resin injection machine for supplying molten resin to the injection molding die, is mounted on one end of the molten resin injection machine to inject molten resin A spray nozzle group having a plurality of spray nozzles having different lengths and runner sizes for injecting molten resin into a mold for injecting a molded product and mounted on a lower side of the inlet block. Characterized in that made.

Here, one end of the molten resin injection machine and the inlet block is preferably connected by the runner of the manifold.

In addition, it is preferable that a plurality of inlet blocks are connected to the runner of the manifold.

In addition, the first direct contact heating means for heating the front end of each injection nozzle, an induction coil portion surrounding the outer edge of the rear end of each injection nozzle having a nozzle tip, and the induction coil portion high frequency power It is preferable to further include a high frequency power supply for supplying a rapid heating of the runner region of the nozzle tip side of each injection nozzle by the electromagnetic force of the induction coil.

In addition, a second direct contact heating means for heating the central portion of each injection nozzle may be further provided.

In addition, the first and second contact heating means may be a band heater or a hot wire heater.

In addition, a temperature sensor line for sensing the temperature of the runner region of the nozzle tip side of each injection nozzle may be wound together with the induction coil unit.

In addition, it is preferable that a separate integrated controller is electrically connected to the induction coil units of the respective injection nozzles so that the rapid heating of each induction coil unit is automatically integrated.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention.

Here, the multi-point gate method according to the present invention is to apply a plurality of injection nozzles having various sizes or lengths to a mold for manufacturing one product such as a gear or a small electronic product. This is a method of implementing a plurality of nozzle gates for injecting molten resin into a product.

The non-contact high frequency induction according to the present invention is more energy efficient and precise management of the operation compared to the conventional equipment using fossil fuels such as coal and petroleum, so that it is possible to produce a homogeneous high-quality product and does not cause pollution. Due to its advantages, it is widely used in various industries. The principle of the high frequency induction is to generate a high frequency magnetic field by flowing a high frequency current through a donut-shaped coil using an electromagnetic induction action, so that the induced current flows in the heating material in the high frequency magnetic field. This induced current generates losses caused by eddy currents swirling in the object and Joule heat due to hysteresis loss and generates heat in a very short time. The heating using the heat generated in this way is called induction heating, and the use of high frequency current is called high frequency induction heating. Due to the use of high frequency high frequency currents, magnetic flux and eddy currents are concentrated on the surface layer of the heating object due to the skin action and proximity effect of the current, and the heat loss (eddy current loss, hysteresis loss) generated at this time heats the surface layer of the heating object. . With this principle, since the energy can be concentrated rapidly on the required portion of the object to be heated, efficient and rapid heating is possible, which brings about high productivity and high workability.

1 is a combined state diagram of a non-contact high frequency induction molten resin injection apparatus of a multi-point gate method according to the present invention, Figure 2 is an enlarged cross-sectional view of the injection nozzle of the multi-point gate method of Figure 1, Figure 3 is a multi-point gate method according to the present invention As a control block diagram of the injection nozzle will be described together for convenience.

As shown, the non-contact high-frequency induction molten resin injection apparatus 100 of the multi-point gate method according to the present invention is mounted on one end of the molten resin injection machine 30 and the inlet block 50 for injecting molten resin, and To a spray nozzle group 20 having a plurality of spray nozzles 20a, 20b, and 20c mounted on the lower side of the inlet block 50 and having different lengths and runner sizes for injecting molten resin into the injection molding die. Is done.

In the injection molding die 10, a core plate (not shown) is positioned on a substantially flat base (not shown), and cavity plates (not shown) are mutually engaged on the core plate for manufacturing the appearance of the injection molded product. It is supposed to be. Here, the injection molding mold 10 according to the present invention in the manufacture of a single product, such as a small electronic product or gear, the amount or injection position of the molten resin injected in accordance with the shape or structure of the product is various Injection nozzles 20a, 20b and 20c having a size and width are required. In addition, although not shown, the injection molding die 10 is composed of a fixed side mold and a movable side mold to be moved and separated at the time of taking out the product. Here, the mold applied in the present invention is preferably applied to the injection molding of gears or small electronic products, but the type and size are not limited.

The inlet block 50 is mounted at one end of the molten resin injector 30, and therein, the injection nozzle runners of the injection nozzles 20a, 20b, and 20c having various sizes or widths therein. Inlet block runners 51 (51a, 51b, 51c) of diverging sizes for supplying molten resins corresponding to the sizes of 60a, 60b, 60c are formed.

A spray nozzle group consisting of a plurality of spray nozzles 20 (20a, 20b, 20c) mounted at a lower side of the inlet block 50 and having different lengths and runner sizes for injecting molten resin into an injection mold; 20) is formed.

Each of the spray nozzles 20 (20a, 20b, 20c) of the spray nozzle group 20 described above may be connected to the inlet block 50 through the spray nozzle runners 60a, 60b, 60c having various sizes. The inlet block runners 51 (51a, 51b, 51b, 51c) are mounted in a form connected to each. Here, although not shown, the heating device of the direct heating method is optionally provided on the outside of the inlet block, and the inlet block runners 51 (51a, 51b, It serves to heat and heat the molten resin raw material in 51c).

Here, the illustrated example shows that the number of injection nozzles is three, but two or four or more may be possible depending on the shape or structure of the product to be molded. That is, the number of injection nozzles formed in the injection nozzle group 20 is formed in at least two or more pieces. In practice, in manufacturing a single product, such as a small electronics or gear, the minimum spacing between each spray nozzle is approximately 6 mm, more preferably 7 mm, but in the present invention the spacing is 6 mm or less or more. Of course, all of them are applicable.

In addition, the respective injection nozzles 20a, 20b, and 20c have different total lengths of the injection nozzles depending on the injection position of the molten resin in the cavity (not shown in the figure).

Meanwhile, as shown in FIG. 2, first and second direct contact heating means 70a, 70b, 70c and 71a are provided at the front and center portions of the respective injection nozzles 20a, 20b, and 20c having various sizes and lengths. , 71b, 71c are formed, and the outer edge of the rear end of each injection nozzle 20a, 20b, 20c in which the nozzle tips 21a, 21b, 21c are formed is an induction coil part 22a as a non-contact high frequency induction heating apparatus. , 22b, 22c) are wound.

In addition, as illustrated in FIG. 3, a high frequency power supply unit 80, which is electrically connected to each of the induction coil units 22a, 22b, and 22c and supplies high frequency power, is further installed to provide the induction coil units 22a and 22b. Connecting the molten resin injection molding machine 30 and the injection molding die 10 by the electromagnetic force of 22c, and the nozzle tips 21a, 21b, 21c of the injection nozzles 20a, 20b, and 20c, which are the most sensitive parts, The injection nozzle runners 60a, 60b, and 60c can be heated rapidly. In addition, a separate integrated controller 90 is electrically connected to each of the induction coil units 22a, 22b, and 22c, so that rapid heating of each induction coil unit is integrated in the integrated controller 90 as one controller. Control is possible. As such, the reason why the induction coil unit can be shared by the integrated control in one controller is that the injection nozzle runner toward the nozzle tip 21a, 21b, 21c (rear end) of each injection nozzle 20a, 20b, 20c. Since the size of 60a, 60b, 60c is almost the same or similarly narrowed, unlike its tip and center, each induction coil part 22a, 22b, 22c can be easily set by a predetermined setting program in one controller. It will be possible to integrate control.

On the other hand, since the temperature difference of the molten resin injected into the front end and the center of each of the injection nozzles 20a, 20b, and 20c close to the molten resin injection machine 30 and the inlet block 50 does not occur much, each injection First and second direct contact heating means 70a, 70b, 70c (71a) at the tip and center portions of the nozzles 20a, 20b, and 20c, which use the same low-cost direct contact heating method as the conventional band heater. , 71b, 71c) are installed. Here, although the first and second direct contact heating means 70a, 70b, 70c (71a, 71b, 71c) are described mainly with a band heater, a hot wire heater or the like having a circular structure can also be used and the kind of the direct heating means. It is not intended to be limiting. In addition, a non-contact high frequency induction heating unit by an induction coil may be provided in the second direct contact heating means 71a, 71b, 71c on the central portion of the injection nozzles 20a, 20b, 20c.

Although not shown, the temperature for sensing the temperature of the injection nozzle runners 60a, 60b, and 60c toward the nozzle tips 21a, 21b, and 21c together with the induction coil parts 22a, 22b, and 22c described above. The sense sensor line can also be wound together.

Therefore, each induction coil part 22a, 22b, 22c as the non-contact high frequency induction heating apparatus according to the present invention has the various lengths and sizes in which the nozzle tips 21a, 21b, 21c are formed. A plurality of winding nozzles runner 60a, 60b toward the tip of the nozzle tip 21a, 21b, 21c is formed in a coil form by winding a plurality of times along the outer periphery of the rear end of each injection nozzle 20a, 20b, 20c. 60c) Only the area is rapidly heated automatically by the integrated control, and after the injection of the molten resin for the product, it can be directly cooled and solidified to release each injection hole (not shown in the figure).

In this manner, the nozzle tip 22a, 22b, 22c as the non-contact high frequency induction heating apparatus automatically controlled by the integrated control unit 90 is relatively far away from the molten resin injector 30 to generate a relatively large temperature drop. (tip) It is formed only in the outer periphery of the rear end part of the injection nozzles 20a, 20b, and 20c of 21a, 21b, and 21c, and it is the same as the former at the front-end | tip and center part of other injection nozzles 20a, 20b, and 20c. By installing the first and second direct contact heating means 70a, 70b, 70c (71a, 71b, 71c) using a direct contact heating method such as a band heater, a plurality of sizes and lengths for forming a single product The technical and economical efficiency of localized rapid heating of only the necessary parts of the two injection nozzles can be secured together.

Here, the rapid heating by the induction coil unit 22a, 22b, 22c, the high-temperature molten resin from the molten resin injection machine 30 is injection molding mold 10 through the injection nozzle runners (60a, 60b, 60c) The injection nozzle runners 60a, 60b, 60c of the nozzle tips 21a, 21b, 21c before being injected (approximately 1-5 seconds ago; may vary depending on the type of product or the power supply size). The nozzle nozzle runner 60a toward the nozzle tip 21a, 21b, 21c by minimizing the temperature between the nozzle nozzle runners 60a, 60b, 60c and the hot molten resin so that the molten resin flows well. , 60b, 60c) can prevent the resin from hardening.

The induction coil units 22a, 22b, 22c as such non-contact high frequency induction heating apparatus are electrically connected to the high frequency power supply unit 80 that supplies the high frequency power (approximately 20 KHz) to control the high frequency power supply. In fact, in the case of local heating using the induction coil units 22a, 22b, 22c as the non-contact high frequency induction heating apparatus according to the present invention, if the output of 700w at approximately 10-50KHz is sufficient, the heating time is approximately several seconds. Since about 100 degrees or more can be heated, the solidification for short time heating and mold release can be easily performed. In addition, in the non-contact high-frequency induction molten resin injection apparatus 100 according to an embodiment of the present invention injection injection device is made by direct injection of molten resin by each injection nozzle 20a, 20b, 20c without a separate manifold formed Is simplified and thus economically inexpensive.

In addition, although not shown, a spiral groove or a projection may be formed on the outer periphery of the nozzle tip side of each injection nozzle to wind the induction coil portion along the spiral groove or projection.

In the non-contact high frequency induction molten resin injection apparatus 200 shown in FIG. 4, each injection nozzle 20a, 20b, 20c; 20a 'of the molten resin injection machine 30 and the plurality of injection nozzle groups 20; , 20b 'and 20c' are substantially the same except that they are connected by the manifold 40, and the same configuration will be described below with the same reference numerals as in FIG.

As shown in FIG. 4, a multi-point gate type non-contact high frequency induction molten resin injection apparatus 200 according to another embodiment of the present invention includes a molten resin injection machine 30 and a plurality of injection nozzle groups 20 ( The manifold 40 is formed as a resin connector of 20 '). The manifold 40 is preferably at least two spray nozzle groups are installed to be able to mold a number of products.

The manifold 40 is a high temperature molten resin from the molten resin injection machine 30 during the molding of small electronic products or gears through the manifold runner 41 each sprue block (50, 50) Each injection nozzle of the injection nozzle group 20; 20 'via the injection block block runners 51: 51a, 51b, 51c; 51': 51a ', 51b', 51c 'of various sizes diverged from'). 20a, 20b, 20c; 20a ', 20b', 20c 'and remain molten in the runner 41 until they are molded into the product in the injection mold. That is, the heating device 42 of the direct heating system is installed outside the manifold 40, and the insulation of the molten resin raw material in the runner 41 is maintained during the injection of high temperature molten resin for continuous production of molded products. It will only play a role. Here, the inlet block runners 51 (51a, 51b) are transferred to the outside of the inlet block by the transfer heat from the direct heating type heating device 42 of the manifold 40, without a separate direct heating type heating device installed. , 51c) may serve to insulate the molten resin raw material.

On the other hand, such a direct thermal heating structure may be a general rod heater or a cartridge heater and the like, but the present invention does not limit the heating structure.

On the other hand, each injection nozzle 20a, 20b, 20c; 20a 'of the injection nozzle group 20; 20' for inject | molding a molten resin into the runner gate (not shown in figure) of the injection mold 10, and shape | molding. 20b ', 20c') nozzle tips (21a, 21b, 21c; 21a ', 21b', 21c ') is required to cool and solidify immediately for release with the shortest heating time, so that the manifold (40) The first and second direct contact heating means 70a, 70b of the tip and center of the heating device 42 and the respective injection nozzles 20a, 20b, 20c; 20a ', 20b', 20c 'using the direct heating method , 70c; 70a ', 70b', 70c ') (71a, 71b, 71c; 71a', 71b ', 71c'), the nozzle tips 21a, 21b, 21c; 21a ', 21b', 21c ' Injection nozzle runners 60a, 60b, 60c; 60a ', 60b' at the lower end of each injection nozzle 20a, 20b, 20c; 20a ', 20b', 20c 'of the formed injection nozzle group 20; 20'. Induction coil portion 22a as a non-contact high frequency induction heating apparatus wound in the form of a coil along the outer periphery of 22b, 22c; 22a ', 22b', and 22c '. The induction coil units 22a, 22b, 22c; 22a ', 22b', and 22c 'also have an integrated controller 90 (see FIG. 3) electrically connected to each other to provide rapid heating of a part of each induction nose. Of course, the integrated control unit 90 as a controller can be integrated.

The nozzle tips 21a, 21b, 21c; 21a ', 21b', 21c 'are formed by the formation of the induction coil parts 22a, 22b, 22c; 22a', 22b ', 22c' using the non-contact high frequency induction method. Locally rapid injection nozzle runners 60a, 60b, 60c; 60a ', 60b', 60c 'in the lower end portions of the formed injection nozzles 20a, 20b, 20c; 20a', 20b ', and 20c'. After the injection of the molten resin for the injection product, it is allowed to cool and solidify immediately to release the inlet (not shown in the figure).

In addition, the inlet blocks 50 and 50 'and the manifold 40 of the spray nozzle groups 20 and 20' are formed in a detachable structure such as a screwing method and the like. It can be formed in conformity with, thereby improving the attachment efficiency.

Therefore, the non-contact high frequency induction molten resin injection apparatus 200 according to another embodiment of the present invention, the manifold 40 and the lower end and the center of each injection nozzle while maintaining the conventional direct heating method, the nozzle tip of each injection nozzle Only the formed lower end is to apply the induction heater by the magnetic field to present a new concept of hot runner (hot runner) structure to be able to satisfy the economy and quality at the same time.

According to the non-contact high-frequency induction molten resin injection apparatus of the multi-point gate method according to the present invention configured as described above, a plurality of injections having various sizes or lengths in a mold for manufacturing one small product, such as gears and small electronic products By applying the spray nozzle group consisting of the nozzles, there is an effect that can be adapted to the change in the amount or the injection position of the molten resin injected in accordance with the shape or structure of the product.

Further, the induction coil portion as a non-contact high frequency induction heating apparatus is formed only on the outer circumference of the nozzle tip side of each injection nozzle, which is relatively far from the molten resin injector, where a large relative temperature drop occurs, and the induction coil portions are integrated. By electrically connecting to the integrated control unit to control the control of each induction coil unit is possible to share the technical and economical effect can be secured together.

Although the present invention has been described in detail with reference to preferred embodiments according to the present invention, this is only for illustrating the present invention and is not intended to limit the present invention, and those skilled in the art can make various changes and modifications without departing from the scope of the present invention. It should be noted that this is possible as well as this is also within the scope of the present invention.

Claims

In the molten resin injection machine for supplying the molten resin to the injection molding mold,

An inlet block mounted on one end of the molten resin injection machine and configured to inject molten resin;

A multi-point jet nozzle group having a plurality of injection nozzles having different lengths and runner sizes for injecting molten resin into a mold for injecting one molded product, which is mounted on the lower side of the inlet block; Gate type non-contact high frequency induction molten resin injection device.

The method of claim 1,

One end of the molten resin injection machine and the inlet block is a non-contact high frequency induction molten resin injection apparatus of the multi-point gate method, characterized in that connected by the runner of the manifold.

The method of claim 2,

The non-contact high frequency induction molten resin injection device of the multi-point gate method characterized in that a plurality of inlet block is connected to the runner of the manifold.

The method according to claim 1 or 3,

Non-contact high-frequency induction molten resin injection device of the multi-point gate method characterized in that the heating device of the direct heating method is further provided on the outside of the inlet block.

The method according to claim 1 or 2,

First direct contact heating means for heating the tip of each injection nozzle;

An induction coil part surrounding an outer edge of each rear end of each injection nozzle having a nozzle tip formed therein;

The non-contact high-frequency induction of the multi-point gate method further comprises a high-frequency power supply for supplying high-frequency power to the induction coil unit to rapidly heat the runner region of the nozzle tip side of each injection nozzle by the electromagnetic force of the induction coil. Molten resin injection device.

The method of claim 5,

The non-contact high-frequency induction molten resin injection device of the multi-point gate method, characterized in that further provided with a direct second contact heating means for heating the central portion of each injection nozzle.

The method of claim 6,

And said first and second contact heating means are band heaters or hot wire heaters.

The method of claim 5,

A multi-point gate high frequency induction molten resin injection apparatus, characterized in that the temperature sensing sensor line for sensing the temperature of the runner region of the nozzle tip side of each injection nozzle is wound together with the induction coil unit.

The method of claim 5,

A separate integrated controller is electrically connected to the induction coil parts of the respective injection nozzles, so that the high-speed induction molten resin injection apparatus of the multi-point gate method is configured to automatically control the rapid heating of each induction coil part integrally.