CN101574842A

CN101574842A - Injection moulding method of membrane inside mould

Info

Publication number: CN101574842A
Application number: CNA200810096443XA
Authority: CN
Inventors: 荘文德; 李继良; 李吉丰
Original assignee: Asustek Computer Inc
Current assignee: Asustek Computer Inc
Priority date: 2008-05-09
Filing date: 2008-05-09
Publication date: 2009-11-11

Abstract

The invention relates to an injection moulding method of a membrane inside a mould, comprising the following steps: correspondingly adjusting the shape of the membrane according to the shape of a mold cavity inside the mould; then correspondingly placing the membrane into the mold cavity; and finally ejecting a plastic to be moulded in the mould so that the membrane is closely jointed with the plastic.

Description

Injection moulding method of membrane inside mould

Technical field

The present invention is about a kind of injection forming method, especially in regard to a kind of membrane inside mould (In-Molding Film, IMF) injection forming method.

Background technology

Utilize mould ejection formation (Injection Molding) to manufacture a product in a large number and be the technology of extensive use.Can make plastic molded article fast in a large number by device for injection moulding, for example housing of handset shell or mobile computer etc.In addition, more attractive in appearance for making product, more can form pattern in conjunction with diaphragm, and the generation of membrane inside mould (IMF) ejection forming technique is arranged at product.

Figure 1A to Fig. 1 C is the schematic diagram of general injection moulding method of membrane inside mould.Shown in Figure 1A, earlier a diaphragm F1 with predetermined pattern to be inserted in the die cavity 101 of a mould 10, mould 10 has a male model 102 and a master mold 103, and die cavity 101 is formed by male model 102 and master mold 103 matched moulds.Shown in Figure 1B, plastics 111 are penetrated to die cavity 101 for another example, and make plastics 111 be shaped to a base material 112 by an ejaculator 11.Afterwards shown in Fig. 1 C, die sinking also ejects moulding product P1, and moulding product P1 closely is linked to base material 112 and is formed by diaphragm F1.

Yet because diaphragm F1 is tabular, so its rigidity is lower, so that the pressure that jet-out plastic 111 is produced causes diaphragm F1 to depart from, so the side P11 of moulding product P1 shown in Figure 2, diaphragm F1 protrudes in base material 112 and subsides are together.In addition, because the rigidity of diaphragm F1 is not good, so the opposite side P12 at moulding product P1 causes flash, so-called flash be diaphragm F1 with the junction of plastics 111 plastics 111 of not fitting fully so that plastics 111 pass and cover diaphragm F1 via the part of diaphragm F1 protuberance.Because diaphragm F1 departs from and phenomenon such as flash, makes the yield of product significantly reduce, and can't reach quality requirement.

Summary of the invention

Method according to a kind of membrane inside mould ejection formation of the present invention comprises following steps: the shape of a die cavity of foundation one mould inside, the corresponding shape of adjusting a diaphragm; The diaphragm correspondence is inserted in the die cavity; And with a plastics ejection formation in mould, make diaphragm closely be linked to plastics.

From the above, earlier according to the shape of the corresponding moulding diaphragm of die cavity shape adjustments of mould inside, make diaphragm be the non-tablet structure according to the method for a kind of membrane inside mould ejection formation of the present invention, so increase diaphragm rigidity and with the attaching of mould inside.Therefore, when jet-out plastic, diaphragm is owing to stronger rigidity and cooperate the die cavity shape to be attached at mould inside, causes flash so the difficult generation of the pressure that is produced when shooting material diaphragm departs from, and then promote the yield of moulding product of the present invention, and reach quality requirement.

Description of drawings

Figure 1A to Fig. 1 C is the schematic diagram of known injection moulding method of membrane inside mould;

Fig. 2 is the schematic diagram of the obtained moulding product of known injection moulding method of membrane inside mould;

Fig. 3 is the flow chart according to the method for a kind of membrane inside mould ejection formation of preferred embodiment of the present invention;

Fig. 4 A to Fig. 4 D is the schematic diagram according to the method for the membrane inside mould ejection formation of preferred embodiment of the present invention; And

Fig. 5 is the schematic diagram according to the obtained moulding product of method of the membrane inside mould ejection formation of preferred embodiment of the present invention.

The specific embodiment

Hereinafter with reference to correlative type, illustrate that wherein identical assembly will be illustrated with identical reference marks according to the method and the moulding product of a kind of membrane inside mould ejection formation of preferred embodiment of the present invention.

Fig. 3 is the flow chart of the method (being designated hereinafter simply as forming method) of a kind of membrane inside mould (IMF) ejection formation of preferred embodiment of the present invention, and it comprises step S01 to step S06, and Fig. 4 A to Fig. 4 D is the schematic diagram of forming method.Below please refer to Fig. 4 A to Fig. 4 D and arrange in pairs or groups Fig. 3 with the explanation forming method.

At first, step S01 is for providing a diaphragm F2 with a predetermined pattern.The present invention does not limit the kind of predetermined pattern, and it can change according to actual demand.Predetermined pattern can be formed at one of them surface of diaphragm F2, and can be by being formed at diaphragm F2 such as but not limited to screen painting (screen printing), transfer printing (transfer) or ink jet printing modes such as (ink-jet printing).The present invention is the material of limiting diaphragm F2 not also, its for example can be cloth, bamboo chip, carbon fibre, Merlon (Polycarbonate, PC) or polyethylene terephthalate (Polyethylene Terephthalate, PET) etc.

Step S02 is for providing a mould 20 (shown in Fig. 4 B), and mould 20 has a male model 202 and a master mold 203, and die cavity 201 is formed by male model 202 and master mold 203 matched moulds, and the present invention does not limit the kind and the shape of mould 20.

Please refer to shown in Fig. 4 A, step S03 is the shape moulding diaphragm F2 according to mould 20 inner die cavitys 201, makes diaphragm F2 be the non-tablet structure.In the present embodiment, the mode of moulding diaphragm F2 is such as but not limited to hot pressing mode, also can use high pressure mode or high pressure to add hot pressing mode simultaneously, make the non-tablet structure of diaphragm F2 can increase rigidity and with the attaching of mould 20 inside.

Please refer to shown in Fig. 4 B, step S04 is for to insert diaphragm F2 correspondence in the die cavity 201, because diaphragm F2 is the moulding according to die cavity 201 shapes, so diaphragm F2 can firmly be attached at die cavity 201 positions of mould 20 inside, and is difficult for displacement.In the present embodiment, the size of diaphragm F2 can be slightly less than the size of inner die cavity 201, and shown in Fig. 4 C, the edge of the edge of diaphragm F2 and inner die cavity 201 is at a distance of a distance D.

Please refer to shown in Fig. 4 C, step S05 is for providing plastics 211.Step S06 be with plastics 211 ejection formations in mould 20, make diaphragm F2 closely be linked to plastics 211.Plastics 211 penetrate to mould 20 by an ejaculator 21.The present invention does not limit the kind of ejaculator 21, for example screw (screw) or plunger type (plunger), and present embodiment is example with the screw.

It should be noted that in this,,, avoid that generation diaphragm F2 warpage causes flash with the die face interference so present embodiment can make diaphragm F2 when matched moulds by diaphragm F2 and die cavity 201 D that keeps at a distance because diaphragm F2 is different with the shrinkage factor of plastics 211.

Please refer to shown in Fig. 4 D, plastics 211 are shaped to a base material 212, and diaphragm F2 closely is linked to base material 212 and forms a moulding product P2.Fig. 5 is the schematic diagram of moulding product P2, present embodiment is by foundation die cavity 201 shapes moulding diaphragm F2 in advance, thereby promote the rigidity of diaphragm F2, and make diaphragm F2 firmly be attached at die cavity 201 positions of mould 20 inside and be difficult for displacement, and then avoid diaphragm F2 to depart from and cause flash.

In addition, as shown in Figure 5, if the shrinkage factor of plastics 211 is higher than the shrinkage factor (shrinkage factor not only of diaphragm F2, film also can cause the film stretching because of pushing of plastics during moulding), the diaphragm F2 edge of moulding product P2 and distance D that base material 212 edges are reserved are dwindled, for example be reduced into D/2 for distance.

The disclosed step S01 of the method for membrane inside mould ejection formation of the present invention does not limit it and needs process sequence to step S06.Wherein, for example step S03 can finish before step S02, and process sequence is looked closely actual job and decided.

In sum, earlier according to the shape moulding diaphragm of mould inside die cavity, make diaphragm be the non-tablet structure according to the method for a kind of membrane inside mould ejection formation of the present invention, so increase diaphragm rigidity and with the attaching of mould inside.Therefore, when jet-out plastic, diaphragm is owing to stronger rigidity and cooperate the die cavity shape to be attached at mould inside, causes flash so the difficult generation of the pressure that is produced when shooting material diaphragm departs from, and then promote the yield of moulding product of the present invention, and reach quality requirement.

The above only is an illustrative, but not is restricted person.Anyly do not break away from spirit of the present invention and category, and, all should be contained in claims its equivalent modifications of carrying out or change.

Claims

1, a kind of method of membrane inside mould ejection formation is characterized in that, comprises following steps:

According to the shape of the die cavity of mould inside, the corresponding shape of adjusting diaphragm;

Above-mentioned diaphragm correspondence is inserted in the above-mentioned die cavity; And

In above-mentioned mould, make above-mentioned diaphragm closely be linked to above-mentioned plastics the plastics ejection formation.

2, method according to claim 1 is characterized in that, wherein the undersized of above-mentioned diaphragm is in the size of above-mentioned die cavity.

3, method according to claim 1 is characterized in that, has predetermined pattern on the wherein above-mentioned diaphragm.

4, method according to claim 3 is characterized in that, wherein above-mentioned predetermined pattern is formed on the above-mentioned diaphragm by printing, transfer printing or ink-jetting style.

5, method according to claim 1 is characterized in that, the wherein corresponding shape of adjusting diaphragm makes the moulding by hot pressing mode of above-mentioned diaphragm.

6, method according to claim 1 is characterized in that, the wherein corresponding shape of adjusting diaphragm makes the moulding by the high pressure mode of above-mentioned diaphragm.

7, method according to claim 1 is characterized in that, the wherein corresponding shape of adjusting diaphragm makes the moulding by high pressure mode and hot pressing mode of above-mentioned diaphragm.

8, method according to claim 1 is characterized in that, wherein above-mentioned diaphragm is shaped as the non-tablet structure.

9, method according to claim 1 is characterized in that, wherein adjusts the shape of above-mentioned diaphragm, makes above-mentioned matrix identical with the shape of above-mentioned die cavity.

10, method according to claim 1 is characterized in that, wherein the material of above-mentioned diaphragm is cloth, bamboo chip, carbon fibre, Merlon or polyethylene terephthalate.