TWI663041B - Molding method of injection molded product - Google Patents

Abstract

A molding method for injection molding, which is used to eliminate stress marks on the outer surface of the injection molding. The molding method includes the following steps: (a) forming the side wall of the injection molded product in such a way that the continuity gradually becomes thinner toward the free end, wherein the continuous thinning method is inside the side wall of the injection molding product; The outer surface approaches, the thickness of the side wall of the injection molded product gradually decreases toward the free end, and the inner side surface is formed as a continuous surface; and (b) a rib is provided on the inner side surface of the side wall of the injection molded product, The length direction of the rib corresponds to a direction in which the continuity of the side wall gradually becomes thinner. Thereby, the appearance defect of the injection molded product is improved, and the extra processing cost of processing the stress mark is avoided.

Description

Molding method for injection molded products

The present invention relates to a molding method for injection molded products, and more particularly, to a molding method for eliminating stress marks on the outer surface of injection molded products.

Injection molding is a widely used process for today's products. The process mainly includes heating thermoplastics or thermosetting plastics in a flowing state, then pressing them through an injection molding machine, and finally feeding the plastics into a relatively low temperature The mold is cooled and shaped, and the product can be taken out from the mold.

Please refer to FIG. 5, which is a product casing made by injection molding in the prior art. The free end portion of the side wall 31 of the upper cover 3 forms an upper coupling seat portion 311 and an upper mating portion 312 of a stepped structure. The free end portion of the side wall 41 of the lower case 4 also forms a lower coupling seat portion 411 and a lower mating portion 412 of a stepped structure. In other words, the stepped structure of the side wall 41 of the lower case 4 corresponds to the stepped structure of the side wall 31 of the upper cover 3. When the upper cover 3 and the lower case 4 are combined, the upper combined seat portion 311 abuts against the lower mating portion 412 and the upper couple portion 312 abuts the lower combined seat portion 411.

However, due to the uneven thickness of the stepped structure of the side wall 31 of the upper cover 3, the cooling speed of the stepped structure of the side wall 31 is not consistent during the manufacturing process, and the outer surface of the side wall 31 corresponds to the position of the stepped structure, that is, A stress mark 5 is formed on the upper combining seat portion 311 and the upper mating portion 312, thereby causing defects in the appearance of the injection molded product.

Therefore, with respect to the formation of the stress mark 5, the conventional art injects the appearance defects of the molded product through post-processing processing such as painting or matte. However, the post-process processing not only prolongs the manufacturing time of the product, but also increases additional costs. Therefore, the products manufactured by the injection molding method of the prior art have unavoidable appearance defects, and also cannot have good process efficiency due to post-process processing.

Therefore, in order to solve the above problems, an object of the present invention is to provide a molding method capable of eliminating stress marks on the outer surface of an injection molded product.

The technical means adopted by the present invention to solve the problems of the conventional technology is to provide a molding method for injection molding to eliminate stress marks on the outer surface of the injection molding. The molding method includes the following steps: (a) injection The side wall of the molded article is formed to extend toward the free end; and (b) a rib is provided on the inner side of the side wall of the injection molded article, and the extending direction of the rib corresponds to the extending direction of the side wall, so that the rib and the side wall The free ends are collectively connected to a shell.

According to an embodiment of the present invention, a molding method of an injection molded product is provided. In step (a), a side wall of the injection molded product is formed in such a manner that the continuity gradually becomes thinner toward the free end, wherein the continuity The method of gradually thinning is that the inner side surface of the side wall of the injection molded product approaches the outer surface, the thickness of the side wall of the injection molded product gradually decreases toward the free end, and the inner side surface is formed as a continuous surface.

According to an embodiment of the present invention, a molding method for injection molding is provided, wherein the casing has a seat portion and an engaging portion, and the engaging portion of the casing is formed to protrude from the seat portion, and a sidewall of the injection molded product is formed. The free end is abutted against the seat portion, and the rib is abutted against the engaging portion. In step (b), the rib is more protruded to form an extending portion corresponding to the end portion corresponding to the free end of the side wall, and An assembling gap is formed between the extending portion and the inner side surface of the side wall to be fixedly assembled to the engaging portion of the casing.

According to an embodiment of the present invention, a molding method for an injection molded product is provided, further including a step (c): a retaining block is formed on an inner side surface of a side wall of the injection molded product, and the clamping block is used for clamping. An engaging groove coupled to the engaging portion of the casing.

According to an embodiment of the present invention, a molding method for injection molding is provided, wherein a plurality of the ribs are provided on an inner side surface of a sidewall of the injection molding, and in the step (c), the locking block is formed. Between two adjacent ribs.

According to an embodiment of the present invention, a molding method for injecting a molded product is provided, wherein a bottom surface of the fixing block is formed with an inclined surface, and the inclined surface is provided in cooperation with the engaging portion toward the rib assembly direction.

According to an embodiment of the present invention, a molding method of an injection molded product is provided, wherein a height of a rib of the injection molded product is gradually increased along a direction in which the sidewall continuity gradually becomes thinner.

According to an embodiment of the present invention, a molding method of an injection molded product is provided, wherein a rib of the injection molded product protrudes from a free end of a sidewall of the injection molded product; the molding method of the shell includes the following steps: (a ) The side wall of the casing is formed to extend toward the free end; and (b) a rib is provided on the inner side of the side wall of the casing, and the extending direction of the rib corresponds to the extending direction of the side wall of the casing and is convex The free end of the side wall of the shell protrudes, wherein the free end of the side wall of the shell abuts against the free end of the side wall of the injection molded product, and the ribs of the shell abut against the inner side of the side wall of the injection molded product , The ribs of the injection molded product abut against the inner side surface of the side wall of the casing.

The molding method of the injection molded product according to the embodiment of the present invention has the following effects. The side wall of the injection molded product is formed in such a way that the continuity gradually becomes thinner to avoid the phenomenon that the thickness of the side wall structure is not uniform and the cooling rate is not uniform. In addition, the ribs on the inner side of the side wall of the injection-molded product are combined with the free end portion of the side wall of the injection-molded product to be combined with the casing, so as to improve the prior art by using a stepped structure (uneven thickness of the side-wall structure) as the upper cover and the lower case. Combination structure. Thereby, the present invention can improve the absence of the stress marks formed on the outer surface of the injection molded product in the prior art.

1‧‧‧ injection molding

11‧‧‧ sidewall

111‧‧‧Free End

112‧‧‧ inside

113‧‧‧ outer surface

12‧‧‧ rib

121‧‧‧ extension

13‧‧‧Assembly clearance

14‧‧‧ card fixing block

141‧‧‧ bevel

2‧‧‧shell

21‧‧‧ sidewall

211‧‧‧Seat

212‧‧‧ Engagement Department

213‧‧‧Locking slot

214‧‧‧ inside

215‧‧‧Free End

22‧‧‧ rib

3‧‧‧ Upper cover

31‧‧‧ sidewall

311‧‧‧ Upper combined seat

312‧‧‧Upper Confrontation Department

4‧‧‧ lower shell

41‧‧‧ sidewall

411‧‧‧ lower joint seat

412‧‧‧Under

5‧‧‧Stress marks

FIG. 1 is a schematic three-dimensional cross-sectional view showing that a molding method of an injection molded product according to a first embodiment of the present invention is applied to a product shell; FIG. 2 is a view showing an application of a molding method of an injection molded product according to a second embodiment of the present invention A schematic cross-sectional view of a product case; FIG. 3 is a schematic partial cross-sectional view showing a molding method of an injection molded product according to a third embodiment of the present invention applied to a product case; and FIG. 4 is a view showing a fourth embodiment of the present invention FIG. 5 is a schematic three-dimensional cross-sectional view of an injection molding method applied to a product case; and FIG. 5 is a schematic three-dimensional cross-sectional view showing a product case made by injection molding according to the prior art.

Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 to 4. This description is not intended to limit the manner of the present invention, but is one of the embodiments of the present invention.

Please refer to FIG. 1, which shows a molding method of an injection molded product according to a first embodiment of the present invention, which is applied to a product shell to eliminate stress marks on the outer surface of the injection molded product. The molding method includes the following steps: ( a) the side wall 11 of the injection molded product 1 is formed to extend toward the free end 111; and (b) a rib 12 is provided on the inner side surface 112 of the side wall 11 of the injection molded product 1, and the extending direction of the rib 12 corresponds to the side wall 11 In the extending direction, the ribs 12 and the free end 111 of the side wall 11 are collectively connected to a casing 2. Specifically, in step (a), the side wall 11 of the injection molded product 1 is formed in such a manner that the continuity gradually becomes thinner toward the free end, and the manner in which the continuity is gradually thinned is formed in the side wall 11 of the injection molded product 1. The inner side surface 112 approaches the outer surface 113. The thickness of the side wall 11 of the injection molded product 1 faces the free end 111 The direction gradually becomes smaller, and the inner surface 112 is formed as a continuous surface. In addition, the height of the ribs 12 of the injection molded product gradually increases along the direction in which the continuity of the side walls 11 gradually becomes thinner.

Referring to FIG. 1, the side wall 21 of the casing 2 includes a seat portion 211 and an engaging portion 212. The engaging portion 212 of the housing 2 is formed by protruding from the seat portion 211. When the injection molded product 1 is coupled to the casing 2, the free end 111 of the side wall 11 of the injection molded product 1 abuts against the seat portion 211 of the casing 2, and the rib 12 abuts against the engaging portion 212. In detail, both the housing 2 and the injection molded product 1 may be made of plastic and injection molded.

Please refer to FIG. 2. The difference between the molding method of the injection molded product of the second embodiment of the present invention and the first embodiment of the present invention is that in step (b), the ribs 12 and An end portion corresponding to the free end 111 of the side wall 11 is more protruded to form an extension portion 121, and an assembly gap 13 is formed between the extension portion 121 and the inner side surface 112 of the side wall 11 to securely connect the card connected to the housing 2.合 部 212.

Please refer to FIG. 3. The difference between the molding method of the injection molded product of the third embodiment of the present invention applied to the product case and the second embodiment of the present invention lies in the injection molding of the third embodiment of the present invention. The molding method of the product further includes a step (c): a locking block 14 is formed on the inner side surface 112 of the side wall 11 of the injection molded product 1, and the locking block 14 is used to lock a part of the engaging part 212 of the casing.卡 固 槽 213. Specifically, the inner surface 112 of the side wall 11 of the injection molded product is provided with a plurality of ribs 12. In step (c), the retaining block 14 is formed between two adjacent ribs 12. In addition, an inclined surface 141 is formed at the bottom of the fixing block, and the inclined surface 141 is provided in a direction that cooperates with the engaging portion 212 toward the assembly of the ribs 12.

Referring to FIG. 4, the difference between the molding method of the injection molded product according to the fourth embodiment of the present invention and the first embodiment of the present invention lies in that the ribs 12 of the injection molded product 1 protrude from the injection molded product 1 The free end 111 of the side wall 11 and the thickness of the side wall 11 of the injection molded product 1 are equal to the thickness of the side wall 21 of the casing 2. In addition, the molding method of the casing 2 includes the following steps: (a) extending the side wall 21 of the casing 2 toward the free end; and (b) providing a rib 22 on the inner side surface 214 of the side wall 21 of the casing 2, The extending direction of the rib 22 corresponds to the extending direction of the side wall 21 of the casing 2 and protrudes from the free end 215 of the side wall 21 of the casing 2. When the injection molded product 1 is combined with the casing 2, the free end 215 of the side wall 21 of the casing 2 The free end 111 of the side wall 11 of the injection molded product 1 abuts the rib 22 of the housing 2 against the inner side 112 of the side wall 11 of the injection molded product 1, and the rib 12 of the injection molded 1 abuts on the housing 2.内 side 214 of the side wall 21.

In the first embodiment of the present invention, the side wall 11 of the injection molded product 1 is formed in such a manner that the continuity gradually becomes thinner. The free end is connected to the casing 2. Therefore, in order to improve the phenomenon that the stepwise structure (as a coupling structure between the upper cover and the lower case) is used in the prior art, the thickness of the sidewall structure is uneven and the cooling rate is not uniform. Therefore, the present invention can improve the lack of stress marks formed on the outer surface of the injection molded product in the prior art. At the same time, the present invention does not require additional post-processing to eliminate appearance defects formed by pressure marks, so that the present invention has good process efficiency and product competitiveness.

In the second embodiment of the present invention, by forming the extending portion 121 of the rib 12, the injection molded product 1 is fixedly assembled with the engaging portion 212 of the housing 2 in a stable manner. In the third embodiment of the present invention, the fixing block 14 of the injection molded product 1 is fixedly coupled to the fixing groove 213 of the casing 2 so that the injection molded product 1 cannot be detached from the casing 2.

In the fourth embodiment of the present invention, the thickness of the side wall 11 of the injection molded product 1 is the same as the thickness of the side wall 21 of the casing 2 and abut against each other when they are combined to improve the uneven thickness of the injection molded product in the prior art due to the uneven structure of the side wall. (Ie, a stepped structure) and stress marks occur during the cooling process. In addition, the ribs 12 of the injection molded product 1 abut against the inner side surface 214 of the side wall 21 of the casing 2 and the ribs 22 of the casing 2 abut against the inner side surface 112 of the side wall 11 of the injection molded product 1 to strengthen the injection molded product. 1 and the stability of the joint between the housing 2.

The above descriptions and descriptions are merely illustrations of the preferred embodiments of the present invention. Those with ordinary knowledge of this technology may make other modifications based on the scope of the patent application defined below and the above description, but these modifications should still be made. It is the spirit of the present invention and is within the scope of the present invention.

Claims (7)

A molding method for injection molding to eliminate stress marks on the outer surface of the injection molding. The molding method includes the following steps: (a) forming a side wall of the injection molding to extend toward the free end; and (b) A rib is provided on the inner side surface of the side wall of the injection molded product, and the extending direction of the rib corresponds to the extending direction of the side wall, so that the rib and the free end of the side wall are collectively assembled in a shell, wherein in step (a ), The side wall of the injection-molded product is formed in such a manner that the continuity gradually becomes thinner toward the free end, wherein the continuous thinning is such that the inner side surface of the side wall of the injection-molded product approaches the outer surface, and the injection molding The thickness of the side wall of the product gradually decreases toward the free end, and the inner side surface is formed as a continuous surface. The molding method for an injection molded product according to item 1 of the claim, wherein the casing has a seat portion and an engagement portion, and the engagement portion of the casing is formed to protrude from the seat portion. The free end abuts against the seat portion, and the rib abuts against the engaging portion. In step (b), the rib further protrudes to form an extending portion corresponding to the end portion corresponding to the free end of the side wall, and in the step An assembling gap is formed between the extending portion and the inner side surface of the side wall to fix the assembly to the engaging portion of the casing. The molding method of the injection molded product as described in the item 1 or 2 of the request, further comprising a step (c): forming a locking block on the inner side surface of the side wall of the injection molding, and the locking block is used for clamping An engaging groove coupled to the engaging portion of the casing. The molding method of the injection molded product according to item 3 of the claim, wherein the inner side surface of the side wall of the injection molded product is provided with a plurality of the ribs. In the step (c), the locking block is formed on the phase. Between two adjacent ribs. The method for molding an injection molded product according to item 3 of the claim, wherein a bottom surface of the fixing block forms an inclined surface, and the inclined surface is provided in cooperation with the engaging portion toward the rib assembly direction. The molding method of the injection molded product according to item 1 of the claim, wherein the height of the ribs of the injection molded product gradually increases along the direction in which the side wall continuity gradually becomes thinner. The molding method of the injection molded product according to item 1 of the claim, wherein the ribs of the injection molded product protrude from the free end of the side wall of the injection molded product; the molding method of the shell includes the following steps: (a) The side wall of the case is formed to extend toward the free end; and (b) a rib is provided on the inner side of the side wall of the case, and the extending direction of the rib is corresponding to the extending direction of the side wall of the case and protrudes. The free end of the side wall of the case, wherein the free end of the side wall of the case abuts against the free end of the side wall of the injection molded product, and the ribs of the case abut against the inner side of the side wall of the injection molded product. The ribs of the injection molded product abut against the inner side surface of the side wall of the casing.