JPH0839613A - Insert fixing structure of mold - Google Patents

Abstract

PURPOSE:To easily perform the attaching and detaching work of an insert with respect to a mold. CONSTITUTION:An insert mounting hole 22 is provided to the cavity surface 21 of the movable mold 2 opposed to a fixed mold 1 in a recessed state and the insert 7 inserted in the insert mounting hole 22 is fixed to the movable mold 2 by an attaching bolt 5 Since the opening part of the attaching bolt hole 73 bored in the top surface 72 of the insert 7 is closed by the blind plug 10 screwed in the top surface 72 of the insert 7, a molten resin is prevented from flowing in the attaching bolt hole 73. The blind plug 10 is simply detachable with respect to the insert 7 by engaging a driver with the negative groove 103 carved in the top surface 102 of the plug 10 to rotate the plug 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention forms a top surface which constitutes a part of the cavity surface in an insert piece which is detachably fitted in an insert piece mounting hole provided in a cavity surface of a mold. The present invention relates to a molding die fixing structure for a molding die in which a mounting bolt is inserted into a mounting bolt hole opened on a top surface and is screwed into a die to fix the insertion piece to the die.

[0002]

2. Description of the Related Art When a synthetic resin product is injection-molded with a molding die, a common molding die is used to mold a plurality of types of products having different shapes. Pieces are selected and attached.

The insert piece is inserted into an insert piece mounting hole which is recessed in the cavity surface of the molding die and is fixed by a mounting bolt. A mounting bolt hole for inserting the mounting bolt is opened in the cavity surface. If so, the molten resin will flow into it. Therefore, conventionally, a blind plug made of a copper block is tapped into the opening of the mounting bolt hole to close it, thereby preventing the molten resin from flowing into the mounting bolt hole.

[0004]

By the way, in the above-mentioned method using the copper blind plug, it is necessary to remove the blind plug from the blind plug insertion hole when replacing the insert piece. I opened it and carved a female screw with a tap, and pulled out the blind plug using the bolt screwed into this female screw as a clue. Therefore, there has been a problem that it takes a lot of time and labor to replace the incoming pieces.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to facilitate the work of attaching / detaching the insert piece to / from the molding die.

[0006]

In order to achieve the above object, the invention described in claim 1 is an insert piece which is detachably fitted into an insert piece mounting hole provided in a cavity of a mold. A molding die that forms a top surface that constitutes a part of the cavity surface, and inserts a mounting bolt into a mounting bolt hole that opens in this top surface and screws it into the mold to fix the insert piece to the mold. In the insert piece fixing structure, the insert piece is formed with a blind plug insertion hole opening on the top surface, and the blind plug opening is opened on the top surface by screwing the blind plug into the blind plug insertion hole. It is characterized by closing the part.

The invention described in claim 2 is characterized in that, in addition to the structure of claim 1, the screwing direction of the blind plug is perpendicular to the top surface.

The invention described in claim 3 is characterized in that, in addition to the structure of claim 1, the blind plug insertion hole is formed coaxially with the mounting bolt hole.

Further, in the invention described in claim 4, in addition to the structure of claim 1, a copper strip-shaped member interposed between the outer periphery of the blind plug and the inner periphery of the blind plug insertion hole is wound. Is characterized by.

The invention described in claim 5 is, in addition to the structure of claim 1, characterized in that a groove with which the tip of a driver is engaged is formed on the top surface of the blind plug.

Further, in the invention described in claim 6, in addition to the structure of claim 5, the groove is a minus groove, and the direction of the minus groove when the blind plug is completely screwed in is:
It is characterized in that it is parallel to the inclination direction of the top surface with respect to the opening / closing direction of the mold.

[0012]

Embodiments of the present invention will be described below with reference to the drawings.

1 to 4 show a first embodiment of the present invention. FIG. 1 is a sectional view of a molding die, FIG. 2 is a sectional view of a first insert piece (enlarged view of an essential part of FIG. 1), FIG. 3 is a sectional view of the second insert piece, and FIG. 4 is a perspective view of a main part of the movable mold.

[0014] As shown in FIG. 1, the molding die D is for injection molding the body cover W of the motorcycle in a synthetic resin, a fixed die 1 having a cavity surface 1 _1, the cavity surface 2 ₁ A movable mold 2 which has the movable mold 2 which can be brought into and out of contact with the fixed mold 1, an extruding plate 3 arranged inside the movable mold 2, a cylinder 4 for driving the extruding plate 3, and Extrusion pins 6 provided on the extrusion plate 3 and facing the cavity ...
With.

The body cover W of the motorcycle has the
Window for checking brake fluid according to raid
W₁(See FIG. 3) With and without
It These two types of body covers W have a common molding die D
To face the back side of the body cover W so that
Cavity surface 2 of movable mold 2₁Insertion hole that is recessed in the
2₂On the window W₁Molded body cover W without
First piece 7 and window W ₁Body cover W with
The second insert piece 8 for shaping is selectively attached.
ing.

Next, the structure of the first insert piece 7 for forming the body cover W having no window W ₁ will be described with reference to FIGS. 2 and 4.

The first insert piece 7 is a substantially rectangular columnar member extending in the XX direction (hereinafter referred to as the axial direction), which is the moving direction of the movable mold 2, and has a bottom surface 7 ₁ perpendicular to the axial direction. When,
And a top surface 7 ₂ that intersects the axial direction at an angle α.
The top surface 7 ₂ of the first insert piece 7 is the cavity surface 2 _{1 of the} movable mold 2.
In the first embodiment, the inclination angle α of the top surface 7 ₂ is relatively small. The first insert piece 7 is provided with a stepped mounting bolt hole 7 ₃ extending in the axial direction and penetrating from the top surface 7 ₂ to the bottom surface 7 _{1. The} female screw 7 is formed in the small diameter portion of the mounting bolt hole 7 _{3. 3} 'is engraved. The movable mold 2 has a screw hole 2 coaxially connected to the mounting bolt hole 7 _3.
3 is formed. Therefore, the first insert piece 7 is attached to the insert piece mounting hole 2 ₂
The mounting bolts 9 by screwing into the screw hole 2 _3, it is possible to fix the first Nyukoma 7 to the movable mold 2 inserted to the.

The first insert piece 7 is formed with a blind plug insertion hole 7 _{4 which} is open at the top surface 7 ₂ . Blind plug insertion hole 7 ₄
Extends perpendicularly to the top surface 7 ₂ of the first insert piece 7, and a screw hole 7 ₅ is coaxially formed in the bottom portion thereof. By inserting the iron blind plug 10 into the blind plug insertion hole 7 ₄ and screwing the threaded portion 10 ₁ integrally formed at the tip thereof into the screw hole 7 ₅ , the top surface 10 ₂ of the blind plug 10 is moved to the first position. It is flush with the top surface 7 ₂ of the insert piece 7, and at the same time, the inlet opening of the mounting bolt hole 7 ₃ is completely closed by the blind plug 10.

In order to make the top surface 10 ₂ of the blind plug 10 flush with the top surface 7 ₂ of the first insert piece 7, after fixing the first insert piece 7 in the insert piece mounting hole 2 ₂ with the mounting bolt 9, The plug 10 is completely screwed in, and in this state, it is cut with a sander or the like so that the top surface 10 ₂ of the blind plug 10 is flush with the top surface 7 ₂ of the first insert piece 7. Subsequently, a minus groove 10 _{3 with} which the tip of a minus driver engages is formed in the top surface 10 ₂ of the blind plug 10 by electric discharge machining or the like. At this time, the direction of the minus groove 10 ₃ is set to be parallel to the inclination direction of the top surface 10 ₂ .

Therefore, one end of the minus groove 10 ₃ (see FIG.
It is possible to avoid the occurrence of undercut by only inclining only (see a part) in the axial direction. At this time, if the direction of the minus groove 10 ₃ is set to be perpendicular to the inclination direction of the top surface 10 ₂ (direction perpendicular to the paper surface of FIG. 2), undercutting will occur over the entire length of the minus groove 10 _3. And to prevent this, minus slot 1
It is necessary to incline one side of 0 ₃ along the axial direction over the entire length, which significantly increases the processing man-hour.

Next, the structure of the second insert piece 8 for forming the body cover W having the window W ₁ will be described with reference to FIGS. 3 and 4.

The overall shape of the second insert piece 8 is similar to that of the first insert piece 7 described above, and like the first insert piece 7, the top surface 8 ₂
Mounting bolt hole 8 that extends axially from the bottom to the bottom surface 8 _1
3 , and an internal thread 8 ₃ ′ is engraved on the small diameter portion. A window W ₁ is formed on the body cover W on the top surface 8 ₂ of the second insert piece 8.
And the convex portion 8 ₄ is formed which can be brought into close contact with the stationary die 1 to form a said mounting bolt holes 8 ₃ at the center of the convex portion 8 ₄
Opens.

Now, in order to perform injection molding of the body cover W having no window W ₁ with the molding die D, the first insertion piece 7 is inserted into the insertion piece mounting hole 2 ₂ of the movable die 2 and the mounting bolt 9 is used. after fixation, threaded into the port cap 10 so as to close the inlet opening of the mounting bolt holes 7 ₃ minus screwdriver. In this state, the fixed mold 1 and the movable mold 2 are closed, and molten resin is injected into the cavity to mold the body cover W. At this time, the resin flows into the minus groove 10 ₃ of the blind plug 10 to form a protrusion, but since that portion is the back surface of the body cover W, it does not affect the quality of the product.

On the other hand, the window W₁Body cover W with
For injection molding with the shape die D, the insert piece mounting hole of the movable die 2 is used.
2₂Insert the second insert piece 8 into the and fix it with the mounting bolt 9.
The mounting bolt hole 8₃It is necessary to block the entrance opening of
It doesn't matter. Because the fixed mold 1 and the movable mold 2 are
When tightened, the top surface 8 of the second insert piece 8₂Convex portion 8 formed on _Four
Comes into close contact with the fixed mold 1, and the mounting bolt hole 8₃Melt to
This is because the inflow of resin is blocked. Then, the second entry
By using 8, the top surface 8₂Convex part 8_FourAgainst
Since the molten resin does not flow into the corresponding part, the body cover
Window W to W₁Can be opened.

As described above, when replacing the first insert piece 7 and the second insert piece 8, it is only necessary to attach and detach the mounting bolt 9 and the blind plug 10, so that the replacement work can be completed easily and in a short time. it can.

Further, the withdrawn Nyukoma 7,8 from Nyukoma mounting hole 2 ₂ of the movable mold 2, a male thread of Nyukoma vent tool (not shown) of the Nyukoma 7,8 mounting bolt holes 7 _3, 8 _It suffices to screw it into the female screws 7 ₃ ′ and 8 ₃ ′ of ₃ and pull it out.

Next, the structure of the insert pieces 7 and 8 according to the second embodiment of the present invention will be described with reference to FIGS. The first insert piece 7 and the second insert piece 8 of the second embodiment have their top surfaces 7 ₂ , 8 _2.
It is suitable when the inclination angle α of is relatively large (that is, when the inclination angle α is close to a right angle).

As is apparent from FIG. 5, the first insert piece 7 is
Bolt hole 7₃Blind plug insertion hole 7 coaxially with_FourEquipped with
Cage, the mounting bolt hole 7 having an internal thread engraved on the inner surface thereof₃
Is the screw part 10 of the blind plug 10.₁Screw hole for screwing in
7_FiveDoubles as The outer periphery of the blind plug 10 is made of copper
The member 11 is wound and fixed by the knock pin 12.
It Top 10 of blind plug 10₂The same as in the first embodiment
Method of slot 10 ₃Is engraved.

As described above, since the strip-shaped member 11 made of copper is attached to the outer circumference of the blind plug 10, the soft strip-shaped member 11 made of copper is screwed into the blind plug insertion hole 7 ₄ when the blind plug 10 is screwed in. Not only does it fit well to the outer periphery of the blind plug 10 and is less likely to loosen, but it is possible to prevent molten resin from flowing into the gap and causing burrs. Moreover, this order is nearly perpendicular angle of inclination α in the second embodiment, even if reducing the number of processing steps of the blind plug insertion hole 7 ₄ Match the screwing direction of the port cap 10 in the axial direction, of the screwdriver tip Can be fitted in the minus groove 10 ₃ formed on the top surface 10 ₂ of the blind plug 10 and easily rotated.

As is apparent from FIG. 6, the second insert piece 8 of the second embodiment has substantially the same structure as the second insert piece 8 of the first embodiment except that the inclination angle α is relatively large. And the functions are provided, the duplicated description will be omitted.

Thus, also in the second embodiment, the first insert piece 7 and the second insert piece 8 can be easily replaced by simply attaching and detaching the mounting bolt 9 and the blind plug 10.

Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above embodiments, and various design changes can be made.

For example, although the mounting bolt 9 is screwed in the axial direction in the embodiment, the mounting bolt 9 may be slanted with respect to the axial direction. Also, the top surface 10 of the blind plug 10
Instead of engraving the minus groove 10 _{3 in 2} , a plus groove or a hexagonal groove may be engraved. Further, in the embodiment, the injection mold is exemplified, but the present invention can also be applied to a die casting mold.

[0034]

As described above, according to the invention described in claim 1, the blind plug insertion hole opening at the top surface of the insert piece is formed, and the blind plug is screwed into the blind plug insertion hole. Since the opening of the mounting bolt hole that opens on the top surface is closed by means of the blind plug, the blind plug is easily attached and detached while the blind plug prevents the molten metal from flowing into the mounting bolt hole. In addition, it becomes possible to replace it in a short time.

According to the invention described in claim 2,
Since the screwing direction of the blind plug is perpendicular to the top surface of the insert piece, the blind plug can be easily rotated with a tool.

According to the invention described in claim 3,
Since the blind hole is formed coaxially with the mounting bolt hole,
It is possible to reduce the processing man-hours of the blind hole.

According to the invention described in claim 4,
Since the copper band-shaped member intervening between the outer periphery of the blind plug and the inner periphery of the blind plug insertion hole is wrapped, the blind plug is prevented from loosening and the molten metal in the gap between the blind plug and the blind plug insertion hole is prevented. Inflow can be prevented.

According to the invention described in claim 5,
Since the groove for engaging the tip of the driver is formed on the top surface of the blind plug, the blind plug can be easily rotated and removed.

According to the invention described in claim 6,
With the screw plug completely screwed in, the direction of the minus groove formed on the top surface is parallel to the inclination direction of the top surface with respect to the opening and closing direction of the mold, so the undercut caused by the minus groove is minimized. Can be suppressed to

[Brief description of drawings]

FIG. 1 is a sectional view of a molding die.

FIG. 2 is a cross-sectional view of a first insert piece (enlarged view of a main part of FIG. 1)

FIG. 3 is a sectional view of a second insert piece.

FIG. 4 is a perspective view of a main part of a movable mold.

FIG. 5 is a sectional view of a first insert piece according to a second embodiment.

FIG. 6 is a sectional view of a second insert piece according to the second embodiment.

[Explanation of symbols]

2 movable mold (mold) 2 ₁ cavity surface 2 ₂ Nyukoma mounting holes 7 first Nyukoma (Nyukoma) 7 ₂ top surface 7 ₃ mounting bolt holes 7 ₄ blind plug insertion hole 9 mounting bolt 10 port cap 10 ₂ Top surface 10 ₃ Minus groove (groove) 11 Band member 17 Minus driver (driver)

Claims (6)

[Claims] 1. An insert piece (7) which is detachably fitted into an insert piece mounting hole (2 ₂ ) recessed in the cavity surface (2 ₁ ) of a mold (2) is provided with the cavity surface (2 ₁ ). Form a top surface (7 ₂ ) that constitutes a part, insert the mounting bolt (9) into the mounting bolt hole (7 ₃ ) that opens in this top surface (7 ₂ ), and screw it into the mold (2). In the molding die fixing structure of the molding die for fixing the insertion piece (7) to the die (2) by doing, a blind plug insertion hole (7 ₄ ) which is opened in the top surface (7 ₂ ) of the insertion piece (7) ) Is formed and the blind plug (10) is screwed into the blind plug insertion hole (7 ₄ ), thereby closing the opening of the mounting bolt hole (7 ₃ ) opening to the top surface (7 ₂ ). A fixing structure for the insert piece of the molding die, which is characterized in that 2. The insert piece fixing structure for a molding die according to claim 1, wherein a screwing direction of the blind plug (10) is perpendicular to the top surface (7 ₂ ). 3. The blind plug insertion hole (7 ₄ ) is formed coaxially with the mounting bolt hole (7 ₃ ).
Fixing structure for the insert piece of the molding die described. The outer periphery of 4. A blind plug (10), characterized in that winding the belt-shaped member (11) of copper interposed between the inner periphery of the blind plug insertion hole (7 _4), according to claim 1 Fixing structure for the insert piece of the molding die described. 5. The molding die according to claim 1, wherein a groove (10 ₃ ) with which the tip of a driver (17) engages is formed on the top surface (10 ₂ ) of the blind plug (10). Entry frame fixed structure. 6. The groove (10 ₃ ) is a minus groove,
The direction of the minus groove in a state where the blind plug (10) is completely screwed in is parallel to the inclination direction of the top surface (7 ₂ ) with respect to the opening / closing direction of the mold (2), An insert piece fixing structure for a molding die according to claim 5.