KR100978008B1

KR100978008B1 - Cold runner block mold of rubber injection mloding for reducing loss of rubber

Info

Publication number: KR100978008B1
Application number: KR1020090096457A
Authority: KR
Inventors: 김월수; 임단오
Original assignee: 한국씰텍주식회사
Priority date: 2009-10-09
Filing date: 2009-10-09
Publication date: 2010-08-25

Abstract

PURPOSE: A Cold Rubber Block mold used for rubber injection molding for reducing a rubber loss is provided to reduce material waste by directly injecting materials through a runner part. CONSTITUTION: A CRB mold(100) used for rubber injection molding for reducing a rubber loss comprises a CRB body(120), a middle hot plate(130), a lower mold(140), and a lower fixing plate(150). A cold runner part(124) of the CRB body injects rubber solution into a cavity(S). The middle plate has an upper mold(132), a heating plate(134), and a heat insulating plate(136). The upper mold has multiple upper forming foams. The heating plate preheats the upper mold. Te heat insulating plate prevents heat from being transferred to the CRB body. The lower mold forms the cavity with the upper mold. The lower fixing plate separates the upper and lower molds.

Description

Cold runner block mold of rubber injection mloding for reducing loss of rubber

The present invention relates to a CRB mold used for rubber injection molding, and more particularly, a heating plate for preheating the upper mold is separated from the cold runner portion, so that the material filled in the cavity is directly injected through the cold runner portion. This lesser object is to provide a CRB mold for use in rubber injection molding.

In general, the CRB mold used in the rubber injection molding is provided with a heating device at a part for forming a product, and the cold runner part is provided with a low temperature holding part, thereby maintaining a constant temperature of the cold runner part, thereby providing a rubber liquid present in the cold runner part. It refers to a mold of a structure that can be used so that the material is not vulcanized.

That is, in the CRB mold, the temperature of the cold runner portion, which is a supply path of the raw material, is maintained at a relatively low temperature as compared to the mold portion where the product is formed during operation, so that the rubber liquid material filled in the cold runner portion is not vulcanized. Since the rubber liquid material in the cold runner portion is lowered into the cavity of the product molding portion, the rubber liquid material in the cold runner portion can be used for product molding.

However, in the conventional CRB mold, since the cold runner part, the heat insulating plate, and the heating means are sequentially stacked and integrally formed, the hot runner part, which is a supply passage, is used to supply the rubber liquid material into the cavity in which the product is molded. It penetrates and connects the cold runner part and the cavity.

The cold runner part is provided with a low temperature holding part so that the rubber liquid material existing after injecting the rubber liquid material into the cavity is not vulcanized, but the rubber liquid material present in the hot runner part is transferred from the heating means as it is being formed in the cavity. Together with the product being molded, it is vulcanized and remains.

For this reason, in order to achieve a continuous process after the end of product molding, the vulcanized rubber present in the hot runner should be removed and disposed of. As such, the vulcanized rubber discarded in the hot runner part has a problem that the amount of the vulcanized rubber increases significantly as the process continues, causing a waste of resources and an increase in cost.

The present invention is to solve the above problems, the heating part for preheating the mold portion provided with the cavity is separated from the cold runner portion is the loss of the rubber material that the material for molding into the cavity directly injected through the cold runner portion It is to provide a CRB mold used for low rubber injection molding.

In order to achieve the above object, the present invention includes a cold runner block body having a cold runner portion for injecting the rubber liquid material into the upper fixing plate and the cavity in which the rubber liquid material inlet is formed; A top mold detachably disposed below the cold runner block body and provided with a plurality of top molding foams according to a product shape, and stacked on top of the top mold to preheat the top mold to a temperature required for product molding. A heating plate stacked on top of the heating plate and the heating plate and provided as a heat insulating plate for preventing heat from being conducted to the cold runner block body; A lower mold provided separably from the upper mold and having a lower molding foam according to a product shape to form a cavity together with the upper molding foam; And a lower fixing plate stacked on a lower portion of the lower mold and operated by a cylinder to closely contact or separate the upper mold and the lower mold with a predetermined pressing force. Characterized in that the backward sliding movement.

Preferably, a protective plate may be stacked on the upper portion of the heat insulating plate to protect the heat insulating plate.

Preferably, the lower mold may be raised when the reverse of the heating plate is in close contact with the cold runner block body.

Preferably, the rubber liquid material may be injected directly into the lower forming foam through the cold runner portion.

Preferably, after the injection of the rubber liquid material, the lower mold is lowered and the heating plate is advanced so that the upper mold and the lower mold may be in close contact with each other.

Preferably, the cold runner unit includes a runner in which the rubber liquid material introduced from the inlet is moved in a horizontal direction, and a plurality of gates for guiding and injecting the rubber liquid material from the runner into the lower molding foam, wherein the gate includes: It may be provided with an inlet portion having a constant cross-sectional area formed at a lower portion thereof, an intermediate portion formed to gradually become smaller than a cross-sectional area of the inlet portion, and an outlet portion extending a predetermined length to be equal to or expanded to the cross-sectional area of the intermediate portion.

The present invention also includes an injection molding apparatus comprising a CRB mold with little loss of material.

According to the present invention as described above, the heating plate for preheating the upper mold is separated from the cold runner portion and the material filled in the cavity is injected directly through the cold runner portion to reduce the waste of the waste material to reduce the cost and save resources It has an effect.

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

1 is a cross-sectional view of a CRB mold having a low loss of material of the present invention, FIG. 2 is an operation state diagram of a CRB mold having a low loss of material of the present invention, and FIG. 3 is an enlarged cross-sectional view of part A of FIG.

In the following description, the same reference numerals will be used to refer to the same elements even though they are shown in different drawings in order to add reference numerals to the drawings.

CRB mold 100 has a low material loss according to a preferred embodiment of the present invention to remove the hot runner portion by sliding the heating plate 130 before and after the drive means by the drive means and the lower mold in the cold runner portion 124 In order to reduce the loss of the rubber liquid material by allowing the rubber liquid material to directly flow into the 140 side, the cold runner block body 120, the heating plate 130, the lower mold 140, and the lower fixing plate 150 are included. do.

The cold runner block body 120 is provided by being stacked below the upper fixing plate 110, and the rubber liquid material inlet 112 is provided at the upper fixing plate 110 so that the rubber liquid material supplied from the raw material supply unit is cold. The rubber liquid material is supplied to the cavity S formed by the upper mold 132 and the lower mold 140 through the cold runner 124 provided in the runner block body 120.

That is, the upper fixing plate 110 and the cold runner block body 120 is fastened through a fixing means such as a screw bolt (not shown) in a state of being stacked up and down and assembled as one body. In addition, the cold runner block body 120 is provided with a cold runner portion 124 so that the rubber liquid material branches and flows from the rubber liquid material inlet 112 to each cavity S side.

The cold runner unit 124 is a runner 125 which moves in a horizontal direction so that the rubber liquid material introduced from the rubber liquid material inlet 112 can be branched into a plurality of lower molding foams 140a and the runner 125. ) Is provided with a gate 126 formed in the vertical direction to guide and inject the rubber liquid material into the plurality of lower molding foam (140a).

2 and 3, the cold runner part 124 is injected into the rubber liquid material inlet 112 by contacting the end of the gate 126 with the upper end of the lower mold 140 in more detail. The rubber liquid material is moved in a horizontal direction through the runner 125 and flows directly into the lower molding foam 140a formed in the lower mold 140 through a plurality of gates 126 formed in the vertical direction. .

The gate 126 is provided with an inlet 126a, an intermediate part 126b, and an outlet 126c so as to be perpendicular to the runner 125 in a downward direction. The inlet portion 126a is such that the rubber liquid material flowing through the runner 125 is introduced through the rubber liquid material inlet 112 and then moved in a horizontal direction to be introduced into each of the lower forming foams 140a. It is provided to communicate with the runner 125.

In addition, the rubber liquid material introduced through the inlet 126a is filled with the rubber liquid material P through each outlet S through the outlet 126c after moving the intermediate part 126b. .

At this time, the inlet 126a is formed in the same cross-section upper and lower, so as to smoothly distribute the rubber liquid material from the runner 125, as shown in Figure 2 and 3 and the middle portion (126b) Is provided to gradually decrease the cross-sectional area toward the bottom, the outlet portion 126c may be provided to be the same as or enlarged the cross-sectional area of the intermediate portion (126b).

The lower mold 140 and the upper mold 132 are in close contact with the rubber liquid material injected into the lower molding foam 140a, and the excess rubber liquid material is filled into the cavity S by inertia and surface tension. The cross-sectional area of the outlet 126c is smaller than the cross-sectional area of the inlet 126a.

Meanwhile, the upper fixing plate 110 has a heating means 104 such as a heater so that the rubber liquid material introduced through the rubber liquid material inlet 112 can flow smoothly without being vulcanized in the cold runner 124. It may be provided.

In addition, the cold runner block body 120 is provided with a plurality of coolant passages 122 as shown in FIG. 1, in which the coolant supplied from the cooling device passes through the cold runner block body 120 and the cold runner block body. Lower the temperature of 120.

Thus, unlike the upper and lower molds 140, which are heated at a high temperature by the heating plate 134, which will be described later, the rubber liquid filled in the cold runner part 124 is maintained at a relatively low temperature and after one cycle of processing is completed. The material can be reused over and over again.

The heating plate 130 is laminated between the lower mold 140 and the cold runner block body 120 and connected to a driving means (not shown) separately provided to be moved forward and backward in a horizontal direction. The lower mold 140 and the cold runner block body 120 are provided to be separated from each other.

The heating plate 130 is stacked on top of the upper mold 132 and the upper mold 132 having a plurality of upper forming foam (132a) according to the product shape of the upper mold 132 at a temperature required for product molding It includes a heating plate 134 for preheating) and a heat insulating plate 136 stacked on top of the heating plate 134 to prevent heat from being transferred to the cold runner block body 120.

That is, the upper mold 132 forms a cavity S so that the upper molding foam 132a formed according to the shape of the product is matched with the lower molding foam 140a to be described later to mold the product. The mold 132 presses the rubber liquid material filled in the cavity S to form a product by allowing the upper mold 132 to be heated to a set temperature by the heating plate 134 stacked on the top.

In this case, an insulation plate 136 is provided between the heating plate 134 and the cold runner block body 120 to prevent the cold runner block body 120 from being heated to a high temperature by the heating plate 134.

The heat insulating plate 136 is usually made of a material having a weak strength such as asbestos, so that the heat insulating plate 136 is prevented from being damaged by close contact with the cold runner block body 120. The protective plate 138 may be provided in a stack.

As described above, the middle heating plate 130 formed of the upper mold 132, the heating plate 134, and the heat insulating plate 136 is connected to a driving means provided separately, and is provided to slide in a horizontal direction by the operation of the driving means. .

The heating plate 130 is separated from the lower mold 140 and the cold runner block body 120 when the rubber liquid material is filled in the cavity (S) to form a product and the driving means By sliding in the horizontal direction by the retreat so that the lower mold 140 can be in close contact with the cold runner block body 120.

As a result, the rubber liquid material introduced into the cold runner part 124 is directly injected into the lower forming foam 140a through the gate 126.

In this way, the heating plate 130 is separated from the lower mold 140 and the cold runner block body 120 and the rubber is injected to form a product by forming a CRB mold to be moved forward and backward sliding by the drive means The liquid material may be directly injected from the cold runner block body 120 to the lower forming foam 140a without passing through the heat plate 130.

That is, in the conventional CRB mold, since the cold runner block body, the heat insulating plate, the heating plate, and the upper mold are sequentially stacked and integrally formed, the rubber liquid material flowing into the cold runner portion is injected into the cavity formed by the upper mold and the lower mold. In order to achieve this, a cold runner portion and a hot runner portion connecting the cavity are required.

The hot runner portion is formed through the heat insulating plate, the heating plate and the upper mold at one end of the cold runner portion. At this time, the hot runner portion is also heated to a high temperature in the process of preheating the upper mold to a high temperature by a heating plate so as to pressurize the rubber liquid material filled in the cavity to form a product. As a result, the rubber liquid material flowing through the cold runner portion is vulcanized due to the high temperature transmitted from the heating plate and the upper mold, and thus, after the product is molded, the vulcanized portion of the hot runner portion must be removed and disposed of.

However, in the CRB mold 100 of the present invention, the heating plate 130 is detachably provided with the cold runner block body 120 and the lower mold 140, and the rubber liquid material is made to slide forward and backward by a driving means. During the injection of the heating plate 130 to be reversed by the drive means. Thereafter, the lower mold 140 is lifted by the cylinder 102 to be in close contact with the cold runner block body 120 so as to directly flow into the lower molding foam 140a through the gate 126.

This eliminates the need for a separate passage through the heat insulating plate 136 and the heating plate 134 to be connected to the upper forming foam 132a, that is, a hot runner part and the cold runner block body 120 by the heat insulating plate 136. It is possible to reliably block heat that can be transferred from the heating plate 134.

Therefore, the amount of cooling water required to maintain the cold runner block body 120 at a constant temperature can be reduced, and the overall operating time of the cooling device for supplying the cooling water can be reduced, so that the energy saving effect can be expected. Will be.

The lower mold 140 is provided such that the lower molding foam 140a according to the product shape corresponds to the same position as the upper molding foam 132a provided on the lower surface of the upper mold 132. When in close contact with the product forms a cavity (S) is molded.

In addition, a lower fixing plate 150 is formed at the lower portion of the lower mold 140 in combination with the lower mold 140 to be integrally formed to operate the lower mold 140 and the lower fixing plate 150 by the operation of the cylinder 102. The lower mold 140 is brought into close contact with the cold runner block body 120 or the upper mold 132 by lifting up and down.

On the other hand, the lower fixing plate 150 is provided with a heating means 104 such as a heater as in the upper fixing plate 110 is provided to heat the lower mold 140 to a suitable temperature.

Hereinafter, a process of forming a product by operating the CRB mold 100 having a low loss of material configured as described above will be described in detail with reference to FIG. 2.

First, the lower mold 140 seated and fixed to the upper surface of the lower fixing plate 150 is separated from the lower surface of the upper mold 132 by the lowering operation of the cylinder, and the mold is opened (FIG. 2B). The heating plate 130 is reversed and slidably moved by the means (FIG. 2C).

Thereafter, the lower mold 140 is raised by the lifting and lowering operation of the cylinder 102 to be in close contact with the lower surface of the cold runner block body 120, and the rubber liquid material supplied to the rubber liquid material inlet 112 is cold. The gate 126 of the runner part 124 directly flows into the lower forming foam 140a (FIG. 2D).

At this time, the rubber liquid material is heated to a predetermined temperature and gelled or gelled and then introduced into a hydraulic cylinder (not shown) by a transfer screw (not shown), and the rubber liquid material of the gel state is set by a piston of the hydraulic cylinder. Pressurized by the compressive force is conveyed to the rubber liquid material inlet 112 through the discharge hole.

Subsequently, after the rubber molding material is sufficiently filled in the lower forming foam 140a, the lower mold 140 is separated from the cold runner block body 120 by the lowering operation of the cylinder 102 (FIG. 2e), the heating plate 130 is advanced by the driving means and is disposed between the lower mold 140 and the cold runner block body 120. (FIG. 2F)

Next, the lower mold 140 is raised by the lifting and lowering action of the cylinder 102 so that the upper mold 132 is in intimate contact with the upper mold 132 disposed below the middle heating plate 130, and the upper and lower forming foams 140a are formed. ) Is completed, and then the rubber liquid material filled in the lower molding foam 140a is heated to a set temperature to pressurize the gel or gelled rubber liquid material with a set compressive force to complete the molding of the product (FIG. 2g).

Thereafter, when the set time has elapsed and the cylinder 102 is returned to its original state, the elevated lower mold 140 and the lower fixing plate 150 are lowered to separate the upper mold 132 and the lower mold 140 from each other. The molded finished product is seated in the lower molding foam 140a and lowered together, and the worker inspects the molded product and loads it.

The product is withdrawn and loaded, and the operator simply cleans the upper and lower forming foams 140a and then operates the driving means again to reverse the heating plate 130 to repeat the above operation.

Although the present invention has been described in detail above with reference to the drawings in connection with specific embodiments, the present invention is not limited to such specific structures. Those skilled in the art may make various modifications or changes without departing from the spirit and scope of the present invention as set forth in the claims below. However, such modifications or changes are clearly revealed to belong to the scope of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a sectional view of a CRB mold used for rubber injection molding with low loss of rubber material of the present invention.

Figure 2 is an operating state of the CRB mold used in the rubber injection molding with a low loss of the rubber material of the present invention.

3 is an enlarged cross-sectional view of portion A of FIG. 2;

-Explanation of symbols for the main parts of the drawings

100: CRB mold used for rubber injection molding with low loss of rubber material

102 cylinder 104 heating means

110: upper fixing plate 112: rubber liquid material inlet

120: cold runner block body 122: cooling water passage

124: cold runner 125: runner

126: gate 126a: inlet

126b: middle portion 126c: outlet portion

S: cavity 130: heating plate

132: upper mold 132a: upper molding foam

134: heating plate 136: heat insulating plate

138: protective plate 140: lower mold

140a: Lower molding foam 150: Lower fixing plate

Claims

A cold runner block body having a top runner plate having a rubber liquid material inlet formed therein and a cold runner portion for injecting the rubber liquid material into the cavity into which the product is molded;

A top mold detachably disposed below the cold runner block body and provided with a plurality of top molding foams according to a product shape, and stacked on top of the top mold to preheat the top mold to a temperature required for product molding. A heating plate stacked on top of the heating plate and the heating plate and provided as a heat insulating plate for preventing heat from being conducted to the cold runner block body;

A lower mold provided separably from the upper mold and having a lower molding foam according to a product shape to form a cavity together with the upper molding foam; And

And a lower fixing plate stacked on a lower portion of the lower mold and operated by a cylinder to closely contact or separate the upper mold and the lower mold with a predetermined pressing force.

The heat transfer plate is a CRB mold used for rubber injection molding with low loss of rubber material, characterized in that the sliding movement forward and backward in the horizontal direction by the drive means.
The method of claim 1,

CRB mold used for rubber injection molding with a low loss of the rubber material, characterized in that the protective plate is laminated on the upper portion of the insulating plate to protect the insulating plate.
The method of claim 1,

CRB mold used for rubber injection molding with a low loss of rubber material, characterized in that the lower mold is raised to the close contact with the cold runner block body when the middle plate is reversed.
The method of claim 3, wherein

And the rubber liquid material is directly injected into the lower molding foam through the cold runner portion.
The method of claim 4, wherein

CRB mold used for rubber injection molding with low loss of rubber material, characterized in that the lower mold is lowered after the injection of the rubber liquid material and the heating plate is advanced so that the upper mold and the lower mold are in close contact with each other.
The method of claim 1,

The cold runner part includes a runner in which the rubber liquid material introduced from the inlet is moved in a horizontal direction, and a plurality of gates for guiding and injecting the rubber liquid material from the runner into the lower molding foam, wherein the gate has a cross-sectional area downward. Rubber injection molding with low loss of rubber material, characterized in that it is provided with a constant inlet portion and the intermediate portion formed to be smaller than the cross-sectional area of the inlet portion and the outlet portion extending a predetermined length to be equal to or enlarged the cross-sectional area of the intermediate portion. CRB mold used for.
An injection molding apparatus comprising a CRB mold used for rubber injection molding with low loss of rubber material according to any one of claims 1 to 6.