JP3486242B2 - Simultaneous decorative injection molding apparatus and simultaneous decorative injection molding method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a method of attaching a decorative film to the surface of a molded product simultaneously with the injection molding of the molded product by adhering the decorative film to the molding surface of a cavity block for resin molding in advance. The present invention relates to a simultaneous decoration injection molding device and a simultaneous decoration injection molding method that are laminated together.

[0002]

2. Description of the Related Art In a simultaneous decorative injection molding method of this kind, as shown in FIG. 4, a decorative film 52 is fed from a film roll 51 and adsorbed and supported on a surface of a heater unit 53, and then a predetermined size is obtained. On the other hand, while the decorative film 52 is being cut, while heating the decorative film 52, the decorative film 52 is lowered to the inside of the facing gap between the cavity block 54 and the core block 55 together with the heater unit 53, and is provided on the cavity block 54 side. The decorative film 52 is brought into close contact with the molding surface of the cavity block 54 by a negative pressure suction action from a suction hole (not shown) (see (B) and (C) in the figure). The heater unit 53 is used for the cavity block 5.
Waiting until the cavity 4 and the core block 55 retreat from the facing gap, the cavity block 54 and the core block 55 are clamped, and injection molding is performed by a conventional method (FIG. 3D). As a result, the decorative film 52 is attached to the surface of the resin molded product 56 at the same time as molding, and the surface of the molded product 56 is decorated by, for example, a pattern such as wood grain printed in advance on the decorative film 52. The decorated molded product 56 is taken out at the same time when the mold is opened ((E) in the same figure). As shown in FIG. 5, the decorative film 52 has a pattern printing layer 58 formed on a base film 57, and is attached to the surface of a molded product 56 with the base film 57 side as an adhesive surface (for example, , "Plastic Age", Aug. 1992, pp. 191-196).

[0003]

In the conventional molding method as described above, the decorative film 52 is preliminarily molded into the molded product 56.
Since it is difficult to accurately cut the decorative film 52 to the surface of the molded product 56 after cutting it according to the shape of After that, the surplus portion of the decorative film 52 formed on the peripheral portion of the molded product 56 must be manually cut. Therefore, the number of working steps is increased by the trimming processing of the decorative film 52, resulting in an increase in cost, which is not preferable.

As another processing method, as shown in FIG. 6, for example, a molded product 56 is set on a predetermined receiving jig 59 after molding, and a trimming cutter 61 having an air cylinder 60 as a drive source is used. Although it is possible to cut the surplus portion 62 of the decorative film 52 as a scrap, the dimensional variation of the molded product 56 itself and the receiving jig 5
Due to the positioning error of the molded product 56 with respect to 9, it is extremely difficult to accurately cut the decorative film 52 in accordance with the end surface of the molded product 56, and the end portion of the decorative film 52 protrudes from the end surface of the molded product 56. The uncut portion is likely to occur, and the cut shape of the decorative film 52 is likely to be uneven or uneven. As a result, not only the improvement of the appearance quality of the molded product 56 cannot be expected, but also the molded product 56, for example.
When the above is combined with a counterpart component, there is a possibility that troubles such as defective assembly due to the uncut portion of the decorative film 52 may occur.

The present invention has been made in view of the above problems, and it is possible to accurately cut a decorative film, which is attached to the surface of a molded product at the same time as molding, according to the shape of the molded product. An object of the present invention is to provide a simultaneous decorative injection molding device and a simultaneous decorative injection molding method.

[0006]

According to a first aspect of the present invention, there is provided a cavity block and a core block which are arranged to face each other so as to be able to approach and separate from each other, and inside the facing gap formed by the cavity block and the core block and the facing gap. A heating unit that can move back and forth between a position retracted from the inside, and a decorative film that has been cut to a predetermined size is adsorbed and supported by the heating unit, and then the heating unit is opposed to the facing unit. While moving into the gap, the decorative film is heated by the heating unit and brought into close contact with the molding surface of the cavity block by the vacuuming action, and the cavity block and the core block are molded after the heating unit is retracted from the facing gap. At the same time, the decorative film was attached to the surface of the molded product by tightening and performing injection molding. In the decorative injection molding device, the heating unit is moved forward with respect to the molded product left on the core block side by mold opening, and the peripheral portion of the decorative film attached to the molded product is adjusted to the molded product shape. It features a trimming cutter for cutting.

The invention described in claim 2 is characterized in that, in addition to the configuration described in claim 1, the trimming cutter is constituted by a hot blade.

According to a third aspect of the present invention, in addition to the structure of the first or second aspect, the peripheral portion of the decorative film bonded to the molded product is adsorbed and supported on the mold matching surface of the core block. It is characterized in that suction holes are formed.

According to a fourth aspect of the present invention, in addition to the structure according to any one of the first to third aspects, the trimming cutter moves forward and backward with respect to the molded product left on the core block side. A guide rod is fixedly supported by the support, and one of the support and the core block is provided with a guide rod parallel to the operating direction of the trimming cutter, and the other is provided with a guide for guiding the guide rod. It is characterized in that holes are formed.

A fifth aspect of the present invention is a method for performing molding by the simultaneous decorative molding device according to the first aspect, which is a step of performing mold opening with the molded product still attached to the core block side after injection molding. And a step of moving the heating unit into a facing gap between the cavity block and the core block that have been opened to position the trimming cutter at a position facing the molded product, and moving the trimming cutter forward. And a step of cutting a peripheral edge portion of the decorative film attached to the molded product.

[0011]

According to the first aspect of the present invention, the heating unit, which has once retracted during mold clamping and injection molding, advances again into the facing gap between the cavity block and the core block after mold opening, and further heats the same. The trimming cutter provided in the unit moves forward with respect to the molded product left on the core block side. As a result, the surplus portion of the peripheral portion of the decorative film that is attached to and integrated with the surface of the molded product is accurately cut according to the shape of the molded product.

At this time, since the molded product itself is still released from the core block and is still held by the core block at the time of molding, it is not affected by the dimensional variation of individual molded products. It is possible to accurately cut the decorative film from a position matching the end surface of the molded product.

According to the second aspect of the present invention, since the trimming cutter is composed of the hot blade, the decorative film can be cut only by pressing the trimming cutter against the molded product. The mechanism can be simplified.

According to the third aspect of the invention, the surplus portion of the decorative film is cut while being kept in close contact with the core block by the negative pressure suction force of the suction holes on the core block side. The film is surely cut, and it becomes possible to prevent cut mistakes and the like.

According to the fourth aspect of the invention, the support body to which the trimming cutter is fixed is guided by the guide rod and the guide hole in the same direction as the operating direction of the trimming cutter with respect to the core block. Since the forward movement is performed, the relative positional accuracy between the trimming cutter and the molded product is further improved.

According to the invention of claim 5, claim 1
In the same manner as in the invention described in, the molded product is not removed from the core block and is still attached to the core block as it is at the time of molding, and the surplus portion of the decorative film is cut by the trimming cutter. Therefore, the decorative film can be accurately cut according to the shape of the molded product.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIGS. 1 and 2 are explanatory views of a simultaneous decoration injection molding apparatus showing an embodiment of the present invention. The injection molding apparatus is roughly classified into a cavity block 1 as a fixed mold and this cavity block. 1, a movable core block 2 arranged to face 1 and a heating unit 3 and the like.

The cavity block 1 is provided with a suction hole 4 opening to the molding surface 1a which is a part of the cavity, and one end of the suction hole 4 is connected to a vacuum pump (not shown). On the other hand, the cavity block 2 is provided with an ejector plate 6 having an ejector pin 5, and a plurality of suction holes 7 opening to the mold matching surface 2b. One end of the suction hole 7 is also formed. It is connected to a vacuum pump (not shown). The suction hole 7 on the core block 2 side is formed at the same time as the molding as shown in FIG.
Since the peripheral portion of the decorative film 12 attached to the surface of No. 3 is adsorbed and supported, it is set at a position as close as possible to the molding surface 2a on the core block 2 side which is a part of the cavity.

The heating unit 3 includes a frame 8
The heater element 9 supported by the center of the cavity block 1 and the core block 2 are fixedly supported by the slide member 11 of the drive device 10 by the operation of the drive device 10. It is possible to move back and forth between the forward drive position P ₁ located at the position and the retracted position retracted from the facing gap between the cavity block 1 and the core block 2.

The frame 8 of the heating unit 3 is shown in FIG.
Suction hole 1 for adsorbing and supporting the decorative film 12 shown in FIG.
3 is formed, and a thermal blade type trimming cutter 14 having a cutting edge 14a corresponding to the contour shape of the molded product 13 is provided on the back side of the frame 8 as shown in FIG. The trimming cutter 14 is fixedly supported by a support plate 15 as a support, and the support plate 15 is connected to a piston rod 16a of an air cylinder 16 fixed to the frame 8.
In addition, the support plate 15 includes a plurality of guide rods 1.
7 are provided in a projecting manner, while guide holes 18 corresponding to the guide rods 17 are formed in the mold matching surface 2b of the core block 2.
Are formed.

Therefore, by expanding and contracting the air cylinder 16, the trimming cutter 14 moves forward or backward with respect to the core block 2 together with the support plate 15 while being guided by the guide rod 17 and the guide hole 18.

In the injection molding apparatus configured as described above, the film roll is in the same manner as the conventional one with the cavity block 1 and the core block 2 in the mold open state and the heating unit 3 in the retracted position. As shown in FIG. 3, the decorative film 12 sent from the above is adsorbed and supported on the surface of the heater element 9 of the heating unit 3 by the negative pressure suction action of the suction hole 13, and then cut into a predetermined size.

Then, as shown in FIG. 3, the heating unit 3
Is lowered to the advance position P ₁ which is in the facing gap between the cavity block 1 and the core block 2, and then the entire heating unit 3 is brought closer to the cavity block 1 side while heating the decorative film 12. As a result, the decorative film 12 adsorbed and supported on the heating unit 3 side
Is sucked and supported by the molding surface 1a of the cavity block 1 due to the negative pressure suction action of the suction hole 4 on the side of the cavity block 1 and closely adheres, and is vacuum-formed according to the shape of the molding surface 1a.

When the decorative film 12 is vacuum-formed as described above, the heating unit 3 is temporarily retracted to the retracted position, the cavity block 1 and the core block 2 are clamped, and injection molding is performed by a conventional method. Be seen. That is, the molding surface 1a on the side of the cavity block 1 and the molding surface 2 on the side of the core block 2 to which the decorative film 12 is closely adhered in advance.
A predetermined resin material is injected from the sprue portion 19 into the cavity formed by a and the molded product 1 having a predetermined shape.
3 is molded, and at the same time, as shown in FIG.
The decorative film 12 is attached to the surface of the to decorate.

When the injection molding is completed, the cavity block 1 and the core block 2 are opened, and
As shown in, the heating unit 3 again descends to the forward position P ₁ . At the time of this mold opening, the ejector plate 6 on the core block 2 side does not operate at all, the molded product 13 remains attached to the core block 2, and at the same time, the peripheral edge portion 12a of the decorative film 12 integrated with the molded product 2 is sucked. The hole 7 is sucked and supported on the mold matching surface 2b of the core block 2 by the negative pressure suction action.

After that, the trimming cutter 14 is advanced with respect to the core block 2 by the operation of the air cylinder 16, so that the surplus portion 12a of the decorative film 12 attached to the peripheral portion of the molded product 13 is heated by the hot blade. The end face of the molded product 13 is cut by the fusing action of the trimming cutter 14. In this case, the trimming cutter 14
The relative positional accuracy between the molded product 13 and the molded product 13 is guaranteed by the guide effect of the guide rod 17 and the guide hole 18.
Moreover, since the molded product 13 is in close contact with the core block 2 as it is at the time of molding, the surplus portion 12a of the decorative film 12 can be accurately obtained from the end surface of the molded product 13 without being affected by the dimensional variation of the molded product 13. Can be cut.

The surplus portion 12a of the decorative film 12
Is sucked and supported by the mold matching surface 2b of the core block 2 by the negative pressure suction action of the suction hole 7 until it is cut by the trimming cutter 14, and the negative pressure suction force by the suction hole 7 is released after cutting. Therefore, the cutting position accuracy is further improved, and more reliable cutting can be performed.

When the surplus portion 12a of the decorative film 12 is cut as described above, the trimming cutter 14 is retracted by the contraction operation of the air cylinder 16, and the heating unit 3 as a whole is operated by the driving device 10. The molded product 13 is taken out of the core block 2 while the ejector plate 6 on the core block 2 side is ejected based on the operation of an air cylinder (not shown) while retracting to the retracted position.

Here, in the above embodiment, a hot blade type cutter is used as the trimming cutter 14, but instead of this, for example, a push cut type or shear type cutter may be used. Further, the relative positions of the guide rod 17 on the support plate 15 side and the guide hole 18 on the core block 2 side are reversed so that the guide hole is provided on the support plate 15 side and the guide rod is provided on the core block 2 side. Good.

[0030]

According to the first aspect of the present invention, the trimming cutter provided in the heating unit is moved forward with respect to the molded product left on the core block side, thereby adhering it to the surface of the molded product. Since the surplus portion of the combined decorative film is cut, it is not necessary to cut the surplus portion of the decorative film in the subsequent step as in the conventional case, so that it is possible to reduce the processing man-hours and the cost. . In addition, since the molded product is cut while it is still attached to the core block, it can be cut accurately according to the shape of the molded product without being affected by variations in the dimensional accuracy of the molded product. The appearance quality of the molded product can be improved by preventing the uncut portion of the film and the variation in the cut state.

According to the second aspect of the present invention, since the trimming cutter of the hot blade type is used, the decorative film can be cut only by pressing the cutter. There is an advantage that the structure of the drive device can be simplified.

According to the third aspect of the invention, since the excess portion of the decorative film is cut while being kept in close contact with the core block by the negative pressure suction action of the suction hole on the core block side, the cut position There is an advantage that the accuracy is improved and the cutting can be performed more surely so that the occurrence of a cutting error can be prevented.

According to the fourth aspect of the present invention, the trimming cutter moves forward with respect to the molded product on the core block side while being guided by the guide rod and the corresponding guide hole together with the support, so that the trimming cutter is moved forward. There is an advantage that the relative positional accuracy between the cutting cutter and the molded product, and consequently the decorative position of the decorative film is further improved.

According to the invention of claim 5, claim 1
In the same manner as in the invention described in, the molded product is not removed from the core block and is still attached to the core block as it is at the time of molding, and the surplus portion of the decorative film is cut by the trimming cutter. Therefore, it is possible to cut the decorative film accurately according to the shape of the molded product, prevent the uncut portion of the decorative film and the variation in the cut state, and greatly contribute to the improvement of the appearance quality of the molded product. There are advantages.

[Brief description of drawings]

FIG. 1 is a view showing an embodiment of the present invention and is an enlarged view of a main part of FIG.

FIG. 2 is a view showing an embodiment of the present invention and is a cross-sectional explanatory view of an injection molding device immediately after mold opening.

FIG. 3 is a cross-sectional explanatory view of an injection molding device immediately before vacuum molding.

FIG. 4 is a process explanatory view showing an example of a conventional simultaneous decorative injection molding method.

5 is a sectional view of a molded product molded by the molding method of FIG.

FIG. 6 is an explanatory cross-sectional view of a main part showing an example of a conventional method of cutting a decorative film.

[Explanation of symbols]

1 ... Cavity block 2 ... Core block 3 ... Heating unit 4, 7 ... Suction holes 8 ... Frame 9 ... Heater element 12 ... Decorative film 13 ... Molded product 14 ... Trimming cutter 15 ... Support plate 16 ... Air cylinder 17 ... Guide rod 18 ... Guide hole

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) B29C 45/14 B29C 33/18 B29C 45/73

Claims (5)

(57) [Claims] 1. A cavity block and a core block, which are arranged to face each other so as to be able to approach and separate from each other, and can be moved back and forth between a facing gap formed by the cavity block and the core block and a position retracted from the facing gap. A heating unit, which adsorbs and supports a decorative film that has been cut into a predetermined size in advance on the heating unit, and then moves the heating unit into the facing gap and heats the decorative film. The decoration is performed by bringing the cavity block into close contact with the molding surface of the cavity block by heating while heating the unit, and performing the injection molding by clamping the cavity block and the core block after the heating unit retracts from the facing gap. In the simultaneous decorative injection molding apparatus in which a film is attached to the surface of a molded product, the heating unit The trimming cutter that moves forward with respect to the molded product left on the core block side by the mold opening and cuts the peripheral edge of the decorative film attached to the molded product according to the shape of the molded product is provided. A simultaneous decoration injection molding device characterized by the above. 2. The simultaneous decoration injection molding apparatus according to claim 1, wherein the trimming cutter is a hot blade. 3. A suction hole for adsorbing and supporting a peripheral edge portion of a decorative film attached to a molded product is formed on a mold matching surface of the core block.
Alternatively, the simultaneous decoration injection molding device described in 2. 4. The trimming cutter is fixedly supported by a support body that moves forward and backward with respect to a molded product left on the core block side, and one of the support body and the core block is trimmed. There is a guide rod parallel to the operating direction of the cutter for
The simultaneous decoration injection molding device according to claim 1, wherein a guide hole for guiding the guide rod is formed on the other side. 5. A method for molding by the simultaneous decorative molding device according to claim 1, wherein a step of performing mold opening with the molded product still attached to the core block side after injection molding, and a cavity opened by the mold. A step of moving the heating unit into the facing gap between the block and the core block to position the trimming cutter at a position facing the molded product; and advancing the trimming cutter to bond it to the molded product. And a step of cutting a peripheral edge portion of the decorative film, the simultaneous decorative injection molding method.