JP3063475B2 - In-mold transfer molding equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for molding a resin molded article and a decorative pattern of the transferred film at the same time as a resin molded article by bringing a transfer film into close contact with a molding surface of a cavity block for resin molding. The present invention relates to an in-mold transfer molding device configured to transfer the image to the side.

[0002]

2. Description of the Related Art An example of a conventional in-mold transfer molding apparatus is shown in FIGS. This in-mold transfer molding apparatus comprises a fixed core block 1 and a movable mold cavity block 2, and the core block 1 further comprises a runner plate 3 and a core plate 4.

On the core block 1 side, a sprue gate 5 is formed, and on the cavity block 2 side, an ejector mechanism 8 comprising an ejector plate 6 and an ejector pin 7 is provided. Hole 9
Are formed, and a transfer film 10 described later is formed.
A pair of upper and lower clampers 11 also serving as a guide are provided.

The suction hole 9 is connected to a vacuum pump 13 via an electromagnetic valve 12, while a portion of the suction hole 9 facing the molding surface 2a is made of a porous material made of sintered metal or the like. A fixed block 14 is provided. In addition, the clamper 11 is driven by a driving mechanism 15 similar to the ejector mechanism 8 to move in the mold clamping and mold opening directions to perform clamping and unclamping operations.

[0005] As shown in FIG. 10, when the transfer film 10 is set in front of the cavity block 2 with the mold open, the clamper 11 is pulled into the cavity block 2 side, and as shown in FIG. As shown, the transfer film 10 is clamped between the clamper 11 and the cavity block 2. As shown in FIG. 11, a predetermined decorative pattern (including characters, symbols, etc.) 16 is printed on the transfer film 10 in advance.

At this time, when the transfer film 10 clamped by the clamper 11 comes into close contact with the seal rubber 17 on the cavity block 2 side, the space between the transfer film 10 and the molding surface 2a becomes a closed space. . In this state, the electromagnetic valve 12 is opened and the vacuum pump 13
, The pressure in the closed space is gradually reduced through the suction hole 9 and the fixing block 14, and the transfer film 10 is brought into close contact with the molding surface 2a.

When the transfer film 10 is completely adhered to the molding surface 2a, as shown in FIG.
And the cavity block 2 are closed, and the electromagnetic valve 12 is closed.
To perform injection molding.

In this molding step, the decorative pattern 16 of the transfer film 10 is transferred to the molded product W, and finally, the decorative pattern 16 is transferred while the transfer film 10 is left on the mold side. The molded product W is removed from the mold.

[0009]

In the above-described conventional in-mold transfer molding apparatus, the transfer film 10 clamped by the clamper 11 at the upper and lower portions is moved between the transfer film 10 and the molding surface 2a. Is made to closely adhere to the molding surface 2a of the cavity block 2 by the depressurizing action of the closed space, even if the transfer film 10 can be closely adhered to the entire molding surface 2a, There is no guarantee that the adhesion start position (elongation start position) is always constant, and variations in the amount of elongation in each part of the transfer film 10 are likely to occur.

As a result, variations occur in the accuracy of the transfer position of the final molded product W and the decorative pattern 16 on the transfer film 10 side with respect to the final molded product W, and there is a limit in improving the molding quality. Such a variation in the transfer position accuracy becomes a problem particularly when a relatively large decorative pattern 16 as shown in FIG.

The present invention has been made in view of the above problems, and has as its object to provide a structure which improves and stabilizes the transfer position accuracy of a decorative pattern on a transfer film side with respect to a molded product. I have.

[0012]

According to the present invention, a transfer film is preliminarily brought into close contact with a molding surface of a cavity block of a pair of a cavity block and a core block by a vacuum evacuation function, and the mold is clamped. In the in-mold transfer molding device in which a resin material is filled into a cavity formed by the block and the core block to form a molded product, and the decorative pattern on the transfer film side is transferred to the surface of the molded product. At the center of the molding surface of the cavity block, while providing a suction block that can reciprocate between a retracted position that is flush with the molding surface and a forward position that protrudes from the molding surface, the transfer film is a cavity block. Prior to contacting the molding surface, the transfer film is sucked by the suction block at the advance position and drawn into the molding surface Order, is characterized in that a drive means for advancing and retracting drive the adsorption block.

[0013]

According to this structure, before the transfer film comes into contact with the molding surface of the cavity block, the transfer film is sucked by the suction block protruding from the center of the molding surface, and then drawn into the molding surface side. Variations in the amount of elongation at each part of the transfer film are reduced, and the transfer position accuracy of the decorative pattern particularly at the center of the molded product is improved.

[0014]

2 and 3 show an embodiment of the present invention, in which parts common to those of the conventional structure shown in FIGS.

As shown in FIGS. 2 and 3, a support hole 21 is formed at the center of the molding surface 2a of the cavity block 2, and a suction block which forms a part of the molding surface 2a is formed in the support hole 21. 22 is provided so as to be able to advance and retreat. The suction block 22 is formed of a porous material such as a sintered metal similarly to the fixed block 14, while the suction block 22 is shared with the clamper 11 via a rod 23 by an operating plate of a drive mechanism 15. 24.

[0016] Thus, the suction block 22, advanced between with clamper 11, and an advanced position P ₁ projecting from the molding surface 2a, and the molding surface 2a flush state becomes retracted position P ₂ (see FIG. 4) It is designed to retreat.
Then, the support hole 21 into which the suction block 22 is inserted.
Is communicated with the suction hole 9.

In the in-mold transfer molding apparatus configured as described above, as shown in FIGS.
1 is in the unclamped state and the suction block 22
Is in the forward position P ₁ , the transfer film 10 is set on the mold matching surface 2 b side of the cavity block 2 by a film feeding device (not shown).

When the transfer film 10 is set,
The actuating plate 24 of the drive mechanism 15 is actuated, the clamper 11 shifts to the clamping operation as shown in FIG. 1, and the suction block 22 starts the retreat operation. At the same time, the electromagnetic valve 12 is opened and the fixed block by the vacuum pump 13 is opened. Suction from the suction block 14 and the suction block 22 is started.

Then, even before the transfer film 10 is completely clamped by the clamper 11, the transfer film 10 is drawn toward the suction block 22 by the suction negative pressure action of the suction block 22, and 22 is adsorbed. In this case, suction is performed from the fixed block 14 at the same time as the suction from the suction block 22. However, the transfer between the mold mating surface 2 b of the cavity block 2 and the transfer film 10 until the transfer film 10 is completely clamped by the clamper 11. Since there is a gap between the transfer films 10,
Does not work much.

Even when the suction block 22 moves to the retracted position P _{2 in} FIG. 4 together with the clamper 11, the suction block 22 still holds the transfer film 10 by suction, so that the transfer film 10 is held by the suction block. 22 gradually draws in the molding surface 2a side.

Thereafter, as shown in FIG.
1 When fully clamp the transfer film 10 between the cavity block 2, a molding surface 2a flush state vacuum block 22 reaches the retracted position P ₂ at the same time. As a result, the transfer film 10 comes into close contact with the seal rubber 17, so that a negative pressure suction force acts on the closed space between the transfer film 10 and the molding surface 2 a, and the transfer film 10
Adheres to the entire molding surface 2a including the suction block 22.

Thus, the transfer film 10 is formed on the molding surface 2a.
When they come into close contact, as shown in FIG.
And the core block 1 are clamped to start injection molding, and at the same time, the electromagnetic valve 12 is closed. This injection molding is performed by filling the cavity R with a resin material from the injection nozzle 18 through the sprue gate 5 by a conventional method.

In the above-described injection molding process, the decorative pattern 16 (see FIG. 3) of the transfer film 10 set in the cavity R in advance is transferred to the surface of the molded product W.

Thereafter, when the mold is opened after the completion of the injection molding, the transfer film 10 is left on the cavity block 2 side as shown in FIG. 6, while the molded product W is formed by the ejector mechanism 8 as shown in FIG. , The non-product portion Q corresponding to the sprue gate portion is cut and separated.

[0025] Then, simultaneously with the unclamping the clamper 11 under mold open state in FIG. 7, on returning the vacuum block 22 to the forward position P _1, the transfer film 10 by an unillustrated film winding apparatus Is completed by winding a predetermined amount.

As described above, according to the present embodiment, before the transfer film 10 comes into contact with the molding surface 2a, the transfer film 10 is sucked and supported by the suction block 22 disposed at the center of the molding surface 2a and then pulled in. Thereby, the transfer position accuracy of the decorative pattern 16 with respect to the molded article W is improved and stabilized.

FIG. 8 is a diagram showing a second embodiment of the present invention.
In the first embodiment, the suction hole 9 and the electromagnetic valve 12 are shared by the fixed block 14 and the suction block 22, whereas in the present embodiment, the suction holes 9A and 9B are provided for the fixed block 14 and the suction block 22. And electromagnetic valve 12
A and 12B are different from each other in that they are independently connected to the respective vacuum pumps 13A and 13B and their opening and closing timings are individually controlled.

That is, in this embodiment, one of the electromagnetic valves 12B is open from the start of the clamping operation of the clamper 11 to the start of the injection, and the suction action of the suction block 22 is the same as that of the first embodiment. The operation is performed from the start of the clamping operation to the start of the injection, while the other electromagnetic valve 12A is
Is opened from the time when the clamping operation is completed to the time when the injection is started, and only during this time, the suction operation is performed by the fixed block 14 in parallel with the suction operation on the suction block 22.

As described above, according to the second embodiment, the suction force of the suction block 22 alone acts on the transfer film 10 until the clamping operation by the clamper 11 is completed. There is an advantage that the accuracy of the suction position of the film 10 and the accuracy of the transfer position of the decorative pattern 16 (see FIG. 3) to the molded product W are further improved.

FIG. 9 is a diagram showing a third embodiment of the present invention.
2 and 8, a raised character 33 is formed on the surface of a suction block 32 similar to that shown in FIGS. 2 and 8, so that a sinking character is formed in a molding W on the other side. Even when employed, the decorative character paint or the like can be accurately transferred onto the surface of the sinking character finally formed on the molded product W side.

[0031]

As described above, according to the present invention, before the transfer film comes into contact with the molding surface of the cavity block, the transfer film is sucked by the suction block protruding from the center of the molding surface. By being drawn into the molding surface side, before the transfer film is stretched in close contact with the molding surface, the relative positional relationship between the center of the molding surface and the transfer film is determined in advance via the suction block. Therefore, the relative positional relationship between the molding surface and the transfer film is always constant, and the elongation amount of each part of the transfer film is also made uniform. As a result, particularly, the transfer position accuracy of the decorative pattern on the transfer film side with respect to the center portion of the molded product is greatly improved, which can contribute to the improvement of the molding quality.

[Brief description of the drawings]

FIG. 1 is a view showing one embodiment of the present invention, and is an explanatory cross-sectional view when a transfer film is suction-supported by a suction block.

FIG. 2 is an explanatory sectional view showing a state before a transfer film is suctioned by a suction block.

FIG. 3 is an explanatory right side view of the cavity block shown in FIG. 2;

FIG. 4 is an explanatory cross-sectional view when a transfer film is in close contact with a molding surface of a cavity block.

FIG. 5 is an explanatory sectional view at the time of injection molding.

FIG. 6 is an explanatory cross-sectional view when the mold is opened after injection molding.

FIG. 7 is an explanatory cross-sectional view when a molded product is ejected after the mold is opened.

FIG. 8 is an explanatory sectional view showing a second embodiment of the present invention.

FIG. 9 is a perspective view of only a suction block showing a third embodiment of the present invention.

FIG. 10 is an explanatory sectional view of a conventional in-mold injection molding apparatus.

FIG. 11 is an explanatory right side view of the cavity block of FIG. 10;

FIG. 12 is an explanatory cross-sectional view when the transfer film is brought into close contact with a molding surface from the state of FIG. 12;

FIG. 13 is an explanatory cross-sectional view showing a state in which the mold is clamped from the state shown in FIG. 12 and a transition is made to injection molding.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Core block 2 ... Cavity block 2a ... Molding surface 9, 9A, 9B ... Suction hole 10 ... Transfer film 11 ... Clamper 12, 12A, 12B ... Electromagnetic valve 13 ... Vacuum pump 14 ... Fixed block 15 ... Driving mechanism (driving means) 16) Decorative pattern 21 ... Support hole 22 ... Suction block 24 ... Operating plate 32 ... Suction block R ... Cavity W ... Molded product

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B29C 45/14-45/16 B29C 33/12-33/18 B29C 39/10-39/12

Claims (1)

(57) [Claims] 1. A transfer film is preliminarily brought into close contact with a molding surface of a cavity block of a pair of a cavity block and a core block by a vacuum evacuation action, and then a mold is clamped. An in-mold transfer molding device configured to transfer a decorative pattern on the transfer film side to the surface of a molded product while filling the cavity with a resin material to form a molded product; A suction block capable of moving back and forth between a retracted position that is flush with the molding surface and an advanced position that projects from the molding surface, and before the transfer film comes into contact with the molding surface of the cavity block. The suction block in the advanced position to suck the transfer film and pull it into the molding surface. In-mold transfer molding apparatus characterized in that a drive means for withdrawal driven.