KR100642831B1 - Manifold for injection molding apparatus - Google Patents

Abstract

 The present invention relates to a manifold for an injection molding machine, according to the present invention, a heater body is formed on the upper and lower surfaces, the metal main body is formed with a resin flow path for the molten resin to move; A heater rod inserted into the heater groove to generate heat; A heat conductor provided between the resin flow path of the metal body and the heater rod, and having a better thermal conductivity than the metal body; By including, a technique for allowing heat generated from the heater rod to be uniformly input to each point of the resin flow passage is disclosed.

Injection Molding Machine, Manifold, Heater

Description

Manifold for Injection Molding Machines {MANIFOLD FOR INJECTION MOLDING APPARATUS}

1A to 1C are schematic cross-sectional views of a heater rod employed in a manifold for an injection molding machine.

1B and 1C are reference diagrams for explaining the nichrome wire inserted into the heater rod of FIG. 1A.

2 is a table showing thermal conductivity and temperature conductivity of various metals.

Fig. 3 is a schematic diagram for explaining the arrangement of the manifold and the nozzle in the general injection molding machine.

4 is an exploded perspective view of the manifold according to the first embodiment of the present invention.

FIG. 5 is a cross-sectional view taken along line CC of FIG. 4.

6A to 6D are schematic reference diagrams for explaining the working state of the manifold of FIG.

Fig. 7 is a sectional view of the manifold according to the second embodiment of the present invention.

8 is a sectional view of a manifold according to a third embodiment of the present invention.

* Description of the symbols for the main parts of the drawings *

 300: manifold

31: metal body

31a: Heater groove

31b: Resin Euro

32: heater rod

33: thermal conductor

The present invention relates to a manifold for an injection molding machine, and more particularly, to a technology for uniformly transferring heat generated from a heater rod to a resin flow path.

In general, the manifold has a resin flow path connected to the nozzle, and serves to apply heat to prevent the molten resin from moving along the resin flow path.

The conventional manifold is provided with a heater rod for heating the molten resin that moves through the resin flow passage.

The related art of the manifold is disclosed in Korean Patent Laid-Open Publication No. 10-2000-0063840 (name of the invention: manifold of injection molding machine, applicant: induction unemployment, cited technology).

As disclosed in the cited art, the manifold was manufactured by forming a heater groove into which the heater rod can be inserted into the upper and lower surfaces of the metal body, and then inserting and fixing the heater rod into the heater groove.

On the other hand, as shown in Figure 1 (a) of the reference, the heater rod 100 is generally the nichrome wire 13 so as not to be in direct contact with the tube by the insulator 12 having a good thermal conductivity inside the tube (11). It has a configuration wound in the form of this coil. When power is input to the nichrome wire 13, electrical resistance is generated to generate high temperature heat. This high temperature heat is input to the resin flow path through the metal body, so that the molten resin that moves in the resin flow path does not harden during the movement process.

By the way, when the heater rod 100 is inserted into the heater groove, it should be inserted by bending at the curved portion of the heater groove into which the heater rod 100 is inserted, as disclosed in the cited art. As referred to in the bent portion (I), the number of turns of the nichrome wire 13 is relatively small, the amount of heat generated in the region is reduced.

In addition, as shown in (c) of FIG. 1, the number of times the nichrome wire 13 is wound per unit length has often been uneven since the production of the heater rod 100, and the nichrome wire 13 is thin. The thinly wound portion (II) has a relatively small amount of heat generation, and the nichrome wire 13 has a tightly wound portion (III), which has a relatively large amount of heat generation.

Therefore, each point of the metal body will result in a different temperature. In general, the metal body has a material of an iron alloy, and the thermal conductivity of iron is reported to be 62 kPa / 占 폚 as referred to in FIG. That is, the electric conductivity of iron is not so excellent, and when the heat received from the heater rod 100 reaches the resin flow path, the heat input to each point of the resin flow path is non-uniform.

Meanwhile, as shown in FIG. 3, at least two nozzles 32-1 and 32-2 are disposed in one manifold 31, and the injection interruptions of the nozzles 32 are together at the same time. Will be done. To this end, only one inlet hole 31a-1 is formed in the resin flow path 31a in which the resin is injected, and the nozzles 32-1 and 32-2 of the inlet hole 31a-1 are formed. There are outflow holes 31a-2 formed by dividing by the number.

By the way, since the heat input to each point of the resin flow path 31a is uneven, the melted resin moving to the nozzles 32-1 and 32-2 becomes viscous at a specific point (point where there is little heat input) and moves. Due to the slow speed, a difference in the moving speed of the melt may occur, and sometimes the melt may harden. Therefore, even when injection by one nozzle 32-1 is completed, the injection by the other nozzle 32-2 may not be completed. Even in this case, since the nozzles 32-1 and 32-2 are opened and closed at the same time, defects in the injection molding may occur, and in some cases, failure of the injection molding machine will occur.

The present invention has been made to solve the above problems, and even if the heat generated at each point of the heater rod is non-uniform, to provide a manifold for the injection molding machine so that uniform heat can be reached at each point of the resin flow path. For the purpose of

Manifold for injection molding machine according to the present invention for achieving the above object, the heater body is formed on the upper and lower surfaces, the metal main body is formed with a resin flow path for the molten resin is moved; A heater rod inserted into the heater groove to generate heat; And a heat conductor provided between the resin flow path of the metal body and the heater rod, and having a better thermal conductivity than the metal body. Characterized in that it comprises a.

The heat conductor is characterized in that the same material is more specific.

The thermal conductor is inserted into the heater groove of the metal main body, the heat conductor is disposed under the heater groove, and the heater rod is further characterized in that it is disposed above the thermal conductor.

In addition, the manifold for the injection molding machine according to the present invention for achieving the above object, a metal body formed with a heater groove is formed on the upper and lower surfaces, the resin flow channel to move the molten resin; A heater rod inserted into the heater groove to generate heat; And a heat conductor disposed outside the resin flow path so that heat generated from the heater rod can be uniformly transmitted to each point of the resin flow path, and having a better thermal conductivity than the metal body. Characterized in that it comprises a.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

First Embodiment

Figure 4 is an exploded perspective view of the injection molding machine manifold 400 according to the first embodiment of the present invention, Figure 5 is a cross-sectional view cut AA in the state that the manifold 400 of Figure 4 assembled.

4 and 5, the manifold 400 according to the present embodiment includes a metal body 41, a heater rod 42, a heat conductor 43 of the same material, a lid 44, and the like. It is composed.

The above-described configuration will be described in more detail as follows.

The metal body 41 is made of iron for transferring heat generated from the heater rod 42 to the resin flow passage 41a, and the heater groove 41b into which the heater rod 42 can be inserted is disposed on the upper and lower surfaces thereof. It is formed, and the resin flow path 41a through which the molten resin moves is formed.

The heater rod 42 is inserted into and fixed to the heater groove 41b and generates heat by receiving external electric power.

The thermal conductor 43 is a copper material (see FIG. 2) having a higher thermal conductivity than that of the metal body 41, that is, a thermal conductivity of 320 kV / 占 폚, and is inserted into the heater groove 41b. It is disposed under the heater rod 42. That is, the heat conductor 43 is disposed under the heater groove 41b, and the heater rod 42 is disposed above the heat conductor 43.

The cover 44 covers the upper end of the heater groove 41b to prevent the heater rod 42 from being separated.

6A to 6D are cross-sectional views of BB in the state in which the manifold 400 of FIG. 4 is assembled as a working state diagram of the injection molding machine manifold 400 of FIG. 6A to 6D, the operation of the manifold 400 according to the present embodiment will be described.

First, as shown in Fig. 6A, the molten resin moves to the resin flow path 41b in the direction of the dotted arrow by the operation of the injection molding machine, and heat is generated in the heater rod 42.

Heat generated from the heater rod 42 is dissipated to the surroundings, at which time, non-uniform heat generated at each point of the heater rod 42 may be input to each point of the heat conductor 43. That is, in FIG. 6 (a), the portion where the solid arrow is dense has a lot of heat input and the portion where the solid arrow is sloppy is a portion where heat is input less. And relatively less heat is generated on the right side of the heater rod 42. By the way, the heat input unevenly from the heater rod 42 to each point of the heat conductor 43 is thermally distributed within a short time as referred to in Fig. 6B. That is, in the left part that receives a lot of heat and the right part that receives a little heat, the movement of heat such as a dotted arrow is performed in a short time. As a result, as a whole, each point of the thermal conductor 43 reaches a uniform thermal equilibrium state. Thus, the heat reached to the uniform thermal equilibrium at each point of the heat conductor 43 is moved back to each point of the metal body 41 uniformly as shown in (c) of FIG. As is referred to in d) it is uniformly input to each point of the resin flow path (41a). Therefore, almost the same amount of heat is input to the molten resin moving on the resin flow passage 41a regardless of the position.

Second Embodiment

FIG. 7 relates to a manifold 700 of an injection molding machine according to a second embodiment of the present invention. Referring to FIG. 7, the heat conductor 73 having a better thermal conductivity than the metal body 71 may include a heater rod ( It is press-fitted in the specific point between 72 and the resin flow path 71a. That is, in the first embodiment, the heat conductor 43 is disposed below the heater groove 41b, but in the present embodiment, a separate heat conductor hole 71c is disposed between the heater groove 71b and the resin flow passage 71a. After the process, the heat conductor 73 is press-fitted into the heat conductor hole 71c, and the heat generated from the heater rod 72 is averaged at each point through the heat conductor 73 and then input to the resin flow path 71a. I am trying to. Reference numeral 74 is a cover.

Third Embodiment

  8 is a cross-sectional view of a manifold 800 for an injection molding machine according to a third embodiment of the present invention. Referring to FIG. 8, the heat conductor hole 81c is processed into a cylindrical shape on the outside of the resin flow path 81a. By injecting the cylindrical heat conductor 83 having a better thermal conductivity than the metal body 81 into the heat conductor hole 81c, the heat inputted into the resin flow path 81a is rapidly passed at each point through the heat conductor 83. After being averaged, it is input to the resin flow path 81a.

 As described above, the detailed description of the present invention has been made by the embodiments with reference to the accompanying drawings, but the above-described embodiments have been described by way of example only, and the general knowledge in the technical field to which the present invention belongs. The person having ordinary skill in the art can easily carry out other forms of the present invention within the same scope as the above embodiments, or can implement the invention in an equivalent area to the present invention only by the description of the embodiments of the present invention. Therefore, the present invention should not be construed as being limited only to the above-described embodiments, but should be construed to include the contents described in the following claims and their equivalents.

As described above, according to the manifold for the injection molding machine according to the present invention, even if uneven heat is generated at each point in the heater rod, the heat input to each point of the resin flow path is maintained in a uniform state. The moving speed of the molten resin moving to the nozzle side is the same, and there is an effect that can prevent problems such as the molten resin hardening.

Claims (4)

Heater grooves are formed on the upper and lower surfaces, and a metal main body having a resin flow path through which the molten resin is moved; A heater rod inserted into the heater groove to generate heat; And A heat conductor provided between the resin flow path of the metal body and the heater rod, and having a better thermal conductivity than the metal body; Manifold for injection molding machine comprising a. The method of claim 1, The heat conductor is a manifold for injection molding machine, characterized in that the same material. The method of claim 1, The thermal conductor is inserted into the heater groove of the metal main body, the heat conductor is disposed under the heater groove, the heater rod is disposed on the upper side of the heat conductor manifold for injection molding machine. Heater grooves are formed on the upper and lower surfaces, and a metal main body having a resin flow path through which the molten resin is moved; A heater rod inserted into the heater groove to generate heat; And A heat conductor disposed outside the resin flow path so that heat generated from the heater rod can be uniformly transferred to each point of the resin flow path, and having a better thermal conductivity than the metal body; Manifold for injection molding machine comprising a.

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