KR20220065969A - A jig for exterior moulding of vacuum interrupter and manufacturing method for exterior moulding of vacuum interrupter using the same - Google Patents

Abstract

The present invention relates to a jig for an external molding of a vacuum interrupter and a method for manufacturing an external molding of a vacuum interrupter using the same. More specifically, provided is a jig for an external molding of a vacuum interrupter, wherein the jig is divided into a cradle, a body part and a cap part, thermo-diffusion (TD) coating is performed on a molding space to be able to mold the exterior part of the vacuum interrupter uniformly without damage, and the body part having a main molding space formed therein is enveloped with a heating grip part and a cooling grip part alternately to function as a handle while heating and cooling the body part. Disclosed is a method for manufacturing an external molding of a vacuum interrupter using the jig.

Description

A jig for external molding of a vacuum interrupter and a method for manufacturing an external molding of a vacuum interrupter using the same

The present invention relates to a jig for external molding of a vacuum interrupter and a method for manufacturing a vacuum interrupter external molding using the same. A vacuum interrupter that can mold the outside of the interrupter homogeneously and without damage, and replace and wrap around the body part where the main molding space is formed with a heating grip part and a cooling grip part, heating and cooling the body part and serving as a handle at the same time A jig for external molding is provided, and a vacuum interrupter external molding manufacturing method using the jig is disclosed.

A circuit breaker is an electrical protection device that protects load devices and lines from fault currents such as short circuits and ground faults that may occur in electrical circuits. The circuit breaker is a hydraulic circuit breaker using oil as an extinguishing medium, a gas circuit breaker using sulfur hexafluoride (SF6) gas, an inert gas, an air circuit breaker using air as an extinguishing medium, a magnetic circuit breaker using magnetism, It is divided into vacuum circuit breakers using the dielectric strength of vacuum.

The double vacuum circuit breaker is a configuration that separates the circuit and protects the device by extinguishing the arc generated when the normal load is opened and closed and the fault current is interrupted within the vacuum interrupter. Specifically, the arc generated when the movable electrode and the fixed electrode are separated is extinguished by the vacuum in the vacuum interrupter to protect the device, and the inside of the vacuum interrupter where the movable electrode and the fixed electrode are separated is electrically insulated by vacuum, but made of ceramic Since some electricity also flows to the outside of the vacuum interrupter, a separate insulation treatment is required outside the vacuum interrupter in order to increase the dielectric strength.

Although SF6 gas is used for external insulation of the vacuum interrupter, its use is prohibited due to environmental regulations, and a solid insulation method of molding with a resin-based resin such as epoxy is used, but the high voltage current is not completely insulated, In case of solid insulation, there is a problem that the surface is smooth and it is difficult to form in a short time.

Republic of Korea Patent Publication No. 10-0789443 Republic of Korea Patent Publication No. 10-1734050

An object of the present invention is to make the vacuum interrupter easy to install and remove after urethane molding by composing a jig with a cradle, a body part, and a cap part. It is to provide a jig for use.

In addition, it is an object of the present invention to TD coating the molding space in which urethane is injected and molded, so that the cured and cooled urethane molding is easily removed from the jig, so that the exterior of the vacuum interrupter can be molded smoothly and without damage. It is to provide a jig for molding.

In addition, it is an object of the present invention to replace and wrap around the body part where the main molding space is formed with a heating grip part and a cooling grip part, serve as a handle of the jig, and harden and cool the urethane solvent injected into the body part main molding space. It is to provide a jig for external molding of a vacuum interrupter.

The technical problems to be achieved by the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned can be clearly understood by those of ordinary skill in the art from the description of the present invention.

In order to solve the above problems and achieve the object, the present invention provides a vacuum interrupter that is easy to install and separate after molding, so that the molded urethane is not damaged and hardening and cooling of the urethane is easy. A jig for molding and a vacuum interrupter external molding manufacturing method using the same are provided.

Hereinafter, the present specification will be described in more detail.

The present invention relates to a cradle in which a receiving groove corresponding to an end of the electrode is formed in the center of the upper end so that any one of a fixed electrode or a movable electrode of a vacuum interrupter is accommodated; a body part coupled to the upper edge of the cradle and spaced apart from the outer circumferential surface of the vacuum interrupter to form a main molding space into which the urethane mold is to be injected; and a cap portion coupled to the upper end of the body portion to form an upper molding space in which the main molding space extends, and a protruding jaw protruding inward to surround the upper surface of the urethane mold; The main molding space and the upper molding space provide a TD (Thermo Diffusion) coated jig for external molding of the vacuum interrupter.

In the present invention, a spiral insertion groove is formed on the outer circumferential surface of the body portion, and the grip portion is coupled while spirally surrounding the outer circumferential surface of the body portion along the spiral insertion groove and protrudes to the outside of the body portion; may further include there is.

In the present invention, the grip part comprises: a heating grip part having a heating wire formed therein in a direction to spirally surround the outer peripheral surface of the body part; and a cooling grip part in which a refrigerant circulates in a direction to spirally surround the outer peripheral surface of the body part; Thus, the heating grip portion and the cooling grip portion may be selectively coupled to the insertion groove of the body portion.

The present invention comprises the steps of washing a cradle, a body, and a cap, preheating, and applying a release agent to a main molding space of the body constituting the molding space and an upper molding space of the cap; accommodating either the fixed electrode or the movable electrode of the vacuum interrupter in a receiving groove formed in the cradle by washing and preheating the vacuum interrupter; forming a urethane molding space in which urethane is to be molded by combining the body portion and the cap portion with the cradle to combine the main molding space and the upper molding space; injecting a urethane solvent in which a main agent and a curing agent are mixed into the urethane molding space; curing by heating a jig for external molding of a vacuum interrupter into which the urethane solvent is injected; cooling the cured urethane to be separated from the vacuum interrupter external molding jig; and separating the vacuum interrupter external molding jig from the vacuum interrupter molded with the cooled urethane; it also provides a vacuum interrupter external molding manufacturing method comprising a.

In the present invention, between the step of forming the urethane molding space and the step of injecting the urethane solvent, the step of coupling a heating grip part including a heating wire to the outer circumferential surface of the body part is further included, and the curing step is performed with a heating wire of the heating grip part. The step of replacing the heating grip portion coupled to the outer peripheral surface of the body portion with a cooling grip portion through which a refrigerant circulates is further included between the curing step and the cooling step, wherein the cooling step is performed with the coolant of the cooling grip portion can

All matters mentioned in the vacuum interrupter external molding jig and the vacuum interrupter external molding manufacturing method using the same apply unless they contradict each other.

According to the jig for external molding of a vacuum interrupter of the present invention, since the jig is composed of a cradle, a body part and a cap part, it is easy to fasten the vacuum interrupter, and it can be easily removed after urethane molding. can be molded with

According to the jig for external molding of the vacuum interrupter of the present invention, the molding space in which urethane is injected and molded is treated with TD coating, so that the cured and cooled urethane molding is easily removed from the jig, and the exterior of the vacuum interrupter is molded smoothly and without damage. can

According to the vacuum interrupter external molding jig of the present invention, the heating grip part and the cooling grip part are wrapped around the body part where the main molding space is formed, and serve as a handle of the jig, and at the same time, the urethane solvent injected into the body part main molding space can be easily cured and cooled.

The effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the detailed description and description of the claims.

1 is a perspective view showing a part cut out in order to explain the relationship between the vacuum interrupter external molding jig and the vacuum interrupter according to the present invention.
2 is a cross-sectional view illustrating a coupling form of a jig for external molding of a vacuum interrupter according to the present invention.
3 is an exploded cross-sectional view of the cross section of FIG. 2 separated for each configuration in order to explain the coupling form of the vacuum interrupter external molding jig according to the present invention.
4 is a perspective view for explaining the coupling relationship between the body part and the grip part in the jig for external molding of the vacuum interrupter according to the present invention.
5 is a front view of components in the jig for external molding of a vacuum interrupter according to the present invention, showing the front of each configuration in order to explain the relationship between the coupling and replacement of the body part and the grip part.
6 is a block diagram illustrating a method for manufacturing a vacuum interrupter external molding according to the present invention.

The terms used in this specification have been selected as currently widely used general terms as possible while considering the functions in the present invention, but these may vary depending on the intention or precedent of a person skilled in the art, the emergence of new technology, and the like. In addition, in a specific case, there is a term arbitrarily selected by the applicant, and in this case, the meaning will be described in detail in the description of the corresponding invention. Therefore, the term used in the present invention should be defined based on the meaning of the term and the overall content of the present invention, rather than the name of a simple term.

Unless defined otherwise, all terms used herein, including technical and scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in a commonly used dictionary should be interpreted as having a meaning consistent with the meaning in the context of the related art, and should not be interpreted in an ideal or excessively formal meaning unless explicitly defined in the present application. does not

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, the described embodiments of the present invention may be modified in various other forms, and the scope of the present invention is not limited by the embodiments described below. The shapes and sizes of the elements shown in the drawings may be exaggerated for clearer description.

In addition, the term 'a jig for external molding of a vacuum interrupter' used throughout the specification may be briefly abbreviated as 'a jig for molding' or a 'jig', and 'a vacuum interrupter external molding manufacturing method' is a 'moulding manufacturing method' or It may be briefly referred to as a 'manufacturing method'.

On the other hand, the vacuum interrupter coupled to the jig of the present invention constitutes the arc extinguishing part of the vacuum circuit breaker, and is a component in which a fixed electrode and a movable electrode are formed at both ends of a ceramic container. The inside of the vacuum interrupter is made of vacuum, and when the fixed electrode and the movable electrode are separated, the inside is electrically insulated by vacuum, but some electricity also flows to the outside of the vacuum interrupter. In this case, solid molding through epoxy or the like is used. However, solid molding through epoxy has a problem in that it cannot be used for ultra-high voltage because its insulating power is limited. In the present invention, the solid insulation of the vacuum interrupter through urethane is intended to implement an external insulation structure that can express high insulation performance even at ultra-high voltages. An object of the present invention is to disclose a structure of a jig that can be easily and smoothly molded.

1 is a perspective view showing a part cut out to explain the relationship between the vacuum interrupter external molding jig 1 and the vacuum interrupter V according to the present invention, and FIG. 2 is a vacuum interrupter external molding jig according to the present invention ( 1) is a cross-sectional view illustrating the coupling form, and FIG. 3 is an exploded cross-sectional view in which the cross section of FIG. 2 is separated for each configuration in order to explain the coupling form of the vacuum interrupter external molding jig 1 according to the present invention. .

The present invention relates to a jig (1) for external molding of a vacuum interrupter that can easily mount a vacuum interrupter (V) and can easily mold the outside of the vacuum interrupter homogeneously with urethane, and as shown in FIGS. 1 to 3, a cradle (10), a body portion 20, and a cap portion (30).

The cradle 10 is configured to fix the position of the vacuum interrupter V by mounting the vacuum interrupter V before molding, and constitutes the base of the jig 1 . In the center of the upper end of the cradle 10, a receiving groove 11 to which the vacuum interrupter V is coupled is formed, in particular, so that either the fixed electrode V1 or the movable electrode V2 of the vacuum interrupter V is accommodated. , the receiving groove 11 is formed in a shape corresponding to the end of the electrode. On the other hand, the support feet 12 may be formed in the cradle 10 to increase the working height of the jig 1 as a whole, and the support feet 12 are lowered to prevent the jig 1 from falling down during operation. It may be formed in the shape of a bell that gradually widens. In addition, the inside of the support foot 12 may be emptied to facilitate heat dissipation of the cradle 10 , but this is not limited thereto, despite one example. In addition, one end of the vacuum interrupter V inserted into the cradle 10 also needs to be molded with urethane, and around the receiving groove 11 there is a lower molding space (MS2) wider than the diameter of the vacuum interrupter (V). In consideration of the formation of the urethane mold (M) molded to one end of the vacuum interrupter (V), the lower groove (13) may be additionally formed so that one end of the frame protrudes. When the lower edge of the urethane mold M protrudes through the lower groove 13, even if the internal electric field in the vacuum interrupter V is concentrated on the edge, the solid molding is not broken, and durability can be provided. Additionally, the cradle 10 is coupled to the body part 20 to be described later, and to fix the coupling position of the body part 20 and to be tightly coupled with the body part 20 so that the urethane does not leak, the body It may be male and female coupled to the unit 20 . In the male-female coupling between the cradle 10 and the body part 20, the outside of the cradle 10 protrudes as shown, and the inside of the body 20 may protrude correspondingly, but is not limited thereto, and vice versa. is also possible, or male and female coupling may be performed in such a way that the center of one part protrudes and a groove is formed in the other part.

The body part 20 is male and female coupled to the upper edge of the cradle 10. As such, as the body part 20 is formed separately from the cradle 10 and coupled, the vacuum interrupter V is coupled to the jig 1 It is easy, and it is easy to remove the jig 1 after urethane molding. In addition, the body portion 20 is spaced apart from the outer circumferential surface of the vacuum interrupter (V) is formed a main molding space (MS1) into which the urethane mold (M) is to be injected. The position of the vacuum interrupter V is fixed in the cradle 10, and the coupling position of the body 20 is also fixed through the male and female coupling between the body 20 and the cradle 10, the body 20 is It can be equally spaced apart from the vacuum interrupter (V) in all directions at a designed interval. The separation distance between the inner circumferential surface of the body 20 and the outer circumferential surface of the vacuum interrupter V may be appropriately selected in consideration of the vacuum interrupter V external insulating performance. On the other hand, in the main molding space MS1 of the body 20, the lower end is combined with the lower molding space MS2 of the cradle 10, and the upper end is combined with the upper molding space MS3 of the cap portion 30 to be described later. As a result, the body portion 20 is formed in an open shape at both ends. In addition, the lower end of the body portion 20 coupled to the cradle 10 may protrude more than the groove of the cradle 10 , and in this case, a chin for separating the body portion 20 from the cradle 10 is formed to form the body The part 20 can be easily separated from the cradle 10 . And, the upper end of the body portion 20 may be male and female coupled to the cap portion 30 to be described later. For this, the inner surface of the upper end of the body portion 20 is dug deeper than the outer surface, and the cap portion 30 has a corresponding protrusion. can be formed.

The cap part 30 is coupled to the upper end of the body part 20, and as the cradle 10, the body part 20, and the cap part 30 are separated and combined, it is easy to mount the vacuum interrupter (V). , it is easy to separate the jig (1) after molding. And, the upper molding space MS3 extending from the main molding space MS1 of the body part 20 is formed in the cap part 30 , and the lower molding space MS2 of the cradle 10 and the body part 20 are formed. The main molding space MS1 and the upper molding space MS3 of the cap part 30 combine to form a molding space MS into which urethane is injected. On the other hand, the supply hole 31 for injecting the urethane solvent is formed in the cap part 30, and in other words, the upper surface is in a state where the protruding jaw 32 protruding inward to surround and form the upper surface of the urethane mold (M) is formed. is open In this way, the protrusion 32 is formed to wrap the upper surface of the urethane mold (M), so that even the upper surface of the mold (M) is formed smoothly, and the amount to be injected of the urethane mold (M) can be visually checked, so that the amount of urethane solvent can be injected into the jig (1).

On the other hand, the molding space MS consisting of the lower molding space MS2, the main molding space MS1, and the upper molding space MS3 is TD (Thermo Diffusion) coated so that the injected and molded urethane is easily removed. Accordingly, the urethane mold (M) cooled after curing does not stick to the jig (1), is easily separated from the jig (1), and the outside of the vacuum interrupter (V) can be molded smoothly.

On the other hand, the vacuum interrupter external molding jig 1 according to the present invention may further include a grip portion 40 to improve the grip force for removing the jig 1, which is further explained.

4 is a perspective view for explaining the coupling relationship between the body part 20 and the grip part 40 in the vacuum interrupter external molding jig 1 according to the present invention, and FIG. 5 is a vacuum interrupter external molding jig according to the present invention. In the paper jig 1, in order to explain the coupling and replacement relationship between the body portion 20 and the grip portion 40, it is a component front view showing the front of each configuration.

As shown in FIG. 5 , a spiral insertion groove 21 is formed on the outer circumferential surface of the body portion 20 to engage the grip portion 40 , and the grip portion 40 is formed in a spiral shape corresponding to the insertion groove 21 . It is fastened to the insertion groove (21). As the grip part 40 is fastened to the insertion groove 21 , the grip part 40 is coupled while spirally surrounding the outer circumferential surface of the body part 20 , and a part protrudes to the outside of the body part 20 . According to the coupling of the grip part 40 as described above, the outer circumferential surface of the body part 20 has a partially protruding configuration to improve the grip force. force can be applied easily,

Meanwhile, the grip part 40 may be divided into a heating grip part 41 and a cooling grip part 42 . The heating grip part 41 may have a heating wire 41a formed therein in a direction to spirally surround the outer circumferential surface of the body part 20 to heat the body part 20 . The cooling grip part 42 is configured to cool the body part 20 , and the refrigerant 42a may circulate therein in a direction to spirally surround the outer circumferential surface of the body part 20 . In this way, as the heating grip part 41 and the cooling grip part 42 are selectively coupled to the insertion groove 21 of the body part 20, the jig 1 cures the urethane solvent and is cured according to the selective coupling. The urethane can be easily molded by cooling the urethane. On the other hand, as the heating grip part 41 and the cooling grip part 42 are coupled along the insertion groove 21 of the body part 20, the heating and cooling can be evenly applied to the entire body part 20, so that the vacuum interrupter (V) It is possible to mold urethane evenly over the entire exterior.

Since the external molding of the vacuum interrupter can be manufactured through the above-described jig for external molding of the vacuum interrupter, a manufacturing method thereof will be described with reference to FIG. 6 .

6 is a block diagram illustrating a method for manufacturing a vacuum interrupter external molding according to the present invention. The vacuum interrupter external molding manufacturing method according to the present invention comprises the steps of applying a release agent (S1); vacuum interrupter receiving step (S2); urethane molding space forming step (S3); urethane solvent injection step (S5); molding curing step (S6); molding cooling step (S8); and a jig separation step (S9).

The release agent application step (S1) is a step for preparing a jig and easily separating the urethane mold and the jig later. First, the cradle, the body part, and the cap part are washed and preheated. After that, a release agent is applied to the lower molding space of the cradle, the main molding space of the body, and the upper molding space of the cap constituting the molding space. It can be removed to form the external molding of the vacuum interrupter smoothly.

In the vacuum interrupter receiving step (S2), first, the vacuum interrupter before molding is washed and preheated to remove the remaining foreign substances to increase the reliability of the solid molding constituting the external insulation. Then, the vacuum interrupter from which foreign substances have been removed is coupled to the receiving groove formed in the cradle, and this is performed by accommodating either the fixed electrode or the movable electrode of the vacuum interrupter. As described above, one electrode of the vacuum interrupter is accommodated in the receiving groove of the cradle, so that the position of the vacuum interrupter in the jig is fixed.

In the urethane molding space forming step (S3), the body part and the cap part are coupled to the cradle to which the vacuum interrupter is coupled, and the lower molding space, the main molding space, and the upper molding space are combined, thereby forming a urethane molding space in which the urethane is to be molded. . As described above, as the urethane molding space is composed of the separately configured cradle, body, and cap, it is easy to couple the vacuum interrupter to the jig, and it is easy to remove the jig after molding.

In the urethane solvent injection step (S5), the urethane solvent in which the main agent and the curing agent are mixed is injected into the assembled urethane molding space. In this case, the ratio of the main agent and the curing agent may be appropriately selected in consideration of the physical properties of the urethane mold.

The molding curing step (S6) is a step for curing the urethane solvent, which is in a liquid state, into a solid state for injection into the jig, and is performed by heating the entire jig. The heating temperature may vary depending on the physical properties of the urethane, but in general, it can be heated at a temperature of about 60 degrees for about 190 minutes.

The molding cooling step (S8) is a step of reducing the volume of the mold so that it can be separated from the jig by cooling the cured urethane mold. The cooling step may also be suitably selected at a temperature in consideration of the working time, etc., but may be generally performed by cooling at room temperature for 4 hours or more.

In the jig separation step (S9), the jig is sequentially removed from the cooled urethane mold having a reduced volume. Through this, the jig can be easily separated from the vacuum interrupter molded with urethane, and a smooth and homogeneous external molding of the vacuum interrupter can be manufactured.

Additionally, in the vacuum interrupter external molding manufacturing method according to the present invention, between the urethane molding space forming step (S3) and the urethane solvent injection step (S5), the heating grip part coupling step (S4) may be further included. When the heating grip part including the heating wire is coupled to the outer peripheral surface of the body part in the heating grip part coupling step ( S4 ), the molding hardening step ( S6 ) may be performed by heating the body part with the heating wire of the heating grip part. In this case, a separate heating device is unnecessary, and the body portion can be directly heated, thereby increasing energy efficiency.

And, in the vacuum interrupter external molding manufacturing method according to the present invention, a cooling grip replacement step (S7) may be further included between the molding hardening step (S6) and the molding cooling step (S8). As the heating grip part coupled to the outer circumferential surface of the body part is replaced with a cooling grip part through which the refrigerant circulates in the cooling grip part replacement step (S7), the molding cooling step (S8) may be performed by circulating the coolant in the cooling grip part. In this case, the molding manufacturing time can be shortened compared to when cooling at room temperature, and the vacuum interrupter external molding manufacturing efficiency can be increased.

From the above description, those skilled in the art to which the present invention pertains will understand that the present invention may be implemented in other specific forms without changing the technical spirit or essential characteristics thereof. In this regard, it should be understood that the embodiments described above are illustrative in all respects and not restrictive.

1: Jig
10: Cradle
11: accommodation home
12: support feet
13: bottom groove
20: body part
21: insertion groove
30: cap
31: supply hole
32: protruding jaw
40: grip part
41: heating grip part
41a: hot wire
42: cooling grip part
42a: refrigerant
V: vacuum interrupter
V1: fixed electrode
V2: movable electrode
M: mold
MS: molding space
MS1: Main molding space
MS2: lower molding space
MS3: upper molding space

Claims (5)

a cradle in which an accommodating groove corresponding to an end of the electrode is formed in the center of the top so that either one of the fixed electrode or the movable electrode of the vacuum interrupter is accommodated;
a body part coupled to the upper edge of the cradle and spaced apart from an outer circumferential surface of the vacuum interrupter to form a main molding space into which a urethane mold is to be injected; and
It is coupled to the upper end of the body portion to form an upper molding space in which the main molding space is extended, and a cap portion having a protruding jaw protruding inward to surround the upper surface of the urethane mold; including;
The main molding space and the upper molding space in which urethane is injected and molded are TD (Thermo Diffusion) coated, vacuum interrupter external molding jig. The method according to claim 1,
A spiral insertion groove is formed on the outer circumferential surface of the body part,
The vacuum interrupter external molding jig further comprising a; a grip portion that is coupled while spirally surrounding the outer circumferential surface of the body portion along the spiral insertion groove and protrudes to the outside of the body portion. 3. The method according to claim 2,
The grip part,
A heating grip portion having a heating wire formed therein in a direction to spirally surround the outer peripheral surface of the body portion; and
A cooling grip part in which the refrigerant circulates in the direction of spirally surrounding the outer circumferential surface of the body part; consists of,
A vacuum interrupter external molding jig in which the heating grip part and the cooling grip part are selectively coupled to the insertion groove of the body part. washing the cradle, the body, and the cap, preheating, and applying a release agent to the main molding space of the body constituting the molding space and the upper molding space of the cap;
accommodating one of the fixed electrode and the movable electrode of the vacuum interrupter in a receiving groove formed in the cradle by washing and preheating the vacuum interrupter;
forming a urethane molding space in which urethane is to be molded by combining the body portion and the cap portion with the cradle to combine the main molding space and the upper molding space;
injecting a urethane solvent in which a main agent and a curing agent are mixed into the urethane molding space;
curing by heating a jig for external molding of a vacuum interrupter in which the urethane solvent is injected;
cooling the cured urethane to be separated from the vacuum interrupter external molding jig; and
Separating the vacuum interrupter external molding jig from the vacuum interrupter molded with the cooled urethane; vacuum interrupter external molding manufacturing method comprising a. 5. The method according to claim 4,
Between the step of forming the urethane molding space and the step of injecting the urethane solvent, the step of coupling a heating grip portion including a heating wire to the outer peripheral surface of the body portion is further included, and the curing step is performed with a heating wire of the heating grip portion,
Between the curing step and the cooling step, the step of replacing the heating grip portion coupled to the outer circumferential surface of the body portion with a cooling grip portion through which a refrigerant circulates is further included, wherein the cooling step is performed with the coolant of the cooling grip portion. A method for manufacturing an external molding.

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