Injection molding optimization method and injection molded part

Abstract

The invention provides an injection molding optimization method and an injection molded part, and is used for improving thickness marks of an original injection molded part, the injection molding optimization method comprises the following steps: providing an original design scheme, the original injection molded part in the original design scheme comprises a connecting part, the connecting part is provided with a limiting part, and the limiting part is provided with a limiting groove; the limiting piece comprises an overlapping part which is overlapped with the connecting part in the thickness direction of the connecting part; and on the basis of the original injection molding part, reducing the thickness of the overlapping part and / or removing part of the overlapping part. According to the injection molding optimization method, the thickness marks of the appearance of the injection molded part can be effectively improved, and the attractiveness of the injection molded part is improved.

Description

Technical Field

[0001] The present application belongs to the field of plastic injection molding, and more specifically, to an injection molding optimization method and an injection molded part. Background Art

[0002] Plastic injection molding, also known as injection molding or injection molding, is a method of injecting molten plastic material into a mold cavity under high pressure, and then cooling and solidifying to obtain a molded product. At present, there are many areas of excessive thickness in the design and assembly of plastic shells. Injection molding in this area will produce thickness marks on the appearance of the injection molded part. Summary of the invention

[0003] The purpose of the embodiments of the present application is to provide an injection molding optimization method and an injection molded part, so as to improve the technical problem of thickness printing of injection molded parts in the prior art.

[0004] To achieve the above purpose, the technical solution adopted in this application is: to provide an injection molding optimization method for improving the thickness print of the original injection molded part, the injection molding optimization method comprising:

[0005] Providing an original design scheme, wherein the original injection molded part in the original design scheme includes a connecting portion, the connecting portion is provided with a limiting member, and the limiting member includes an overlapping portion overlapping with the connecting portion in a thickness direction of the connecting portion;

[0006] On the basis of the original injection molded part, the thickness of the overlapped part is reduced and / or part of the overlapped part is removed.

[0007] Optionally, the stopper includes a first bone stopper connected to a side surface of the connecting portion, the overlapping portion includes a first overlapping portion, the first overlapping portion is located at the first bone stopper, the first overlapping portion overlaps with the connecting portion, and the first bone stopper also includes an extension portion, the extension portion is connected to the first overlapping portion and extends out of the connecting portion;

[0008] On the basis of the original injection molded part, the thickness of the first overlapping portion on the side away from the connecting portion and the thickness of the extension portion on the side away from the connecting portion are reduced by the same amount, and the thickness of the extension portion on the side facing the connecting portion is increased.

[0009] Optionally, the overlap portion further includes a first rib portion and a second rib portion, the first rib portion and the second rib portion are both connected to the connecting portion, and the first rib portion and the second rib portion are respectively located on both sides of the first overlap portion and extend to both sides of the extension portion;

[0010] On the basis of the original injection molded part, the thickness of the first rib portion facing the second rib portion is reduced, the thickness of the first rib portion facing away from the second rib portion is increased, the thickness of the second rib portion facing the first rib portion is reduced, and the thickness of the second rib portion facing away from the first rib portion is increased.

[0011] Optionally, the limiter includes a second bone stopper, the overlap portion includes a third rib portion and a fourth rib portion located on the second bone stopper, the third rib portion and the fourth rib portion are connected to the side of the connecting portion at intervals, a first stop portion is provided on a side of the third rib portion away from the connecting portion, a second stop portion is provided on a side of the fourth rib portion away from the connecting portion, the first stop portion and the second stop portion are arranged opposite to each other, and an intermediate portion is connected between the first stop portion and the second stop portion, and the third rib portion, the fourth rib portion, the first stop portion and the second stop portion surround a plug-in slot;

[0012] On the basis of the original injection molded part, the thickness of the third rib portion facing the fourth rib is reduced, the thickness of the fourth rib portion facing the third rib is reduced, and the middle portion is removed.

[0013] Optionally, the injection molding optimization method further includes, based on the original injection molded part, improving the texture roughness of the outer surface of the injection molded part, and the texture roughness of the outer surface is positively correlated with the thickness of the overlapped portion;

[0014] And / or, the injection molding optimization method also includes, based on the original design scheme, improving the texture roughness of the inner surface of the injection molded part, and the texture roughness of the inner surface is positively correlated with the thickness of the overlapping portion.

[0015] Optionally, the injection molding optimization method further includes, based on the original design solution, increasing the outer surface draft angle of the original injection molded part.

[0016] Optionally, the injection molding optimization method further includes, based on the original design, adding an exhaust port on the parting surface; and / or, adding an exhaust port next to the glue inlet of the rear mold.

[0017] Optionally, the injection molding optimization method also includes using a duckbill type injection port.

[0018] The present application also provides an injection molded part, which is optimized using the above-mentioned injection molding optimization method.

[0019] The present application also provides an injection molded part, the injection molded part comprising:

[0020] Connecting part;

[0021] A limiting member is arranged on the connecting portion, wherein the limiting member includes an overlapping portion overlapping with the connecting portion in a thickness direction of the connecting portion;

[0022] The thickness of the overlapping portion is not greater than 60% of the thickness of the connecting portion.

[0023] Optionally, the stopper includes a first bone stopper connected to a side surface of the connecting portion, the overlapping portion includes a first overlapping portion, the first overlapping portion is located at the first bone stopper, the first overlapping portion overlaps with the connecting portion, the first bone stopper also includes a first overlapping portion, and the extension portion is connected to the first overlapping portion and extends out of the connecting portion;

[0024] A side of the extension portion facing away from the connecting portion is flush with a side of the first overlapping portion facing away from the connecting portion, and a side of the extension portion facing the connecting portion at least partially overlaps with the connecting portion.

[0025] Optionally, the overlap portion includes a first rib portion and a second rib portion, the first rib portion and the second rib portion are both connected to the connecting portion, and the first rib portion and the second rib portion are respectively connected to two sides of the first overlap portion and extend to two sides of the extension portion;

[0026] The first rib portion and the second rib portion satisfy: D≥T+0.1 mm, wherein D represents the distance between the first rib portion and the second rib portion, and T represents the maximum thickness of the first rib portion and the second rib portion.

[0027] Optionally, the limiting member includes a second bone stop, and the overlapping portion includes a third rib portion and a fourth rib portion located on the second bone stop, the third rib portion and the fourth rib portion are spaced apart and connected to the side of the connecting portion, a first stop portion is provided on the side of the third rib portion away from the connecting portion, and a second stop portion is provided on the side of the fourth rib portion away from the connecting portion, the first stop portion and the second stop portion are arranged opposite to each other, and there is a gap between the first stop portion and the second stop portion.

[0028] Optionally, the thickness of the overlapping portion and the texture roughness of the outer surface of the injection molded part satisfy: X≥22+20*(T-0.6), wherein D represents the maximum thickness of the overlapping portion, and X represents the VDI value of the outer surface of the injection molded part.

[0029] The beneficial effects of the injection molding optimization method and injection molded parts provided in the present application are as follows: the injection molding optimization method of the present application, for the situation where the injection molded part includes a connecting portion, and the connecting portion is provided with a limiting part that overlaps with the connecting portion in the thickness direction, and thickness marks appear on the injection molded part, on the basis of the original injection molded part, the thickness of the overlapping portion is reduced or part of the overlapping portion is removed, thereby effectively improving the thickness marks on the appearance of the injection molded part and improving the aesthetics of the injection molded part. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0031] Figure 1 It is an overall schematic diagram of the injection molded part in the embodiment of the present application;

[0032] Figure 2 It is a schematic diagram of the outer side of a component of the injection molded part in the embodiment of the present application;

[0033] Figure 3 This is a schematic diagram of the inner side of a component of an injection molded part in an embodiment of the present application;

[0034] Figure 4 for Figure 3 The enlarged view of point I in the middle;

[0035] Figure 5 It is a schematic diagram of the inner side plane of a component of the injection molded part in the embodiment of the present application;

[0036] Figure 6 for Figure 5 The enlarged view of II in the middle;

[0037] Figure 7 It is a schematic diagram of the outer side of another component of the injection molded part in the embodiment of the present application;

[0038] Figure 8 It is a schematic diagram of the inner side of another component of the injection molded part in the embodiment of the present application;

[0039] Fig. 9 for Figure 8 Enlarged view of position III in the middle;

[0040] Fig.10 It is a schematic inner plane diagram of another component of the injection molded part in the embodiment of the present application;

[0041] Fig.11 for Fig.10 Enlarged view of position IV in the middle;

[0042] Fig.12 A schematic diagram of the first bone stop of the original injection molded part;

[0043] Fig.13 A schematic diagram of the second bone stop of the original injection molded part;

[0044] Fig.14 A schematic diagram of the position of adding a vent hole to the parting surface of a component of an injection molded part in an embodiment of the present application;

[0045] Fig.15 A schematic diagram of the position of adding a vent hole to the parting surface of another component of the injection molded part in the embodiment of the present application;

[0046] Fig.16 A schematic diagram of the position of an additional exhaust hole next to the rear mold air inlet of a component of an injection molded part in an embodiment of the present application;

[0047] Fig.17 A schematic diagram of the position of an additional exhaust hole next to the rear mold air inlet of another component of the injection molded part in the embodiment of the present application;

[0048] Fig.18 This is a picture of the original injection molded part from the first perspective;

[0049] Fig.19 A second perspective picture of the original injection molded part with thick and thin prints;

[0050] Fig. 20 The third angle view of the original injection molded part with thick and thin prints;

[0051] Fig.21 This is the first perspective picture of the optimized injection molded part;

[0052] Fig. 22 This is a picture of the optimized injection molded part from the second perspective;

[0053] Fig.23 This is a picture of the optimized injection molded part from the third viewing angle;

[0054] Fig.24 This is a picture of the appearance of the injection molded part of Example 1 of the present application;

[0055] Fig.25 This is a picture of the appearance of the injection molded part of Example 2 of the present application;

[0056] Fig.26 This is a picture of the appearance of the injection molded part of Example 3 of the present application;

[0057] Fig. 27 This is an appearance picture of the injection molded part of Example 4 of the present application;

[0058] Fig.28 This is a picture of the appearance of the injection molded part of Example 5 of the present application;

[0059] Among them, the figure marks in the figure are: injection molded part 100, connecting part 110, first bone stop 120, first overlapping part 121, extension part 122, first rib part 123, second rib part 124, second bone stop 130, third rib part 131, fourth rib part 132, first stop part 133, second stop part 134. DETAILED DESCRIPTION

[0060] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0061] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0062] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0063] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0064] See also Figures 1 to 11 The injection molding optimization method provided in the embodiment of the present application is now described. The injection molding optimization method of this embodiment is used to improve the thickness print of the original injection molded part, and the injection molding optimization method includes:

[0065] An original design scheme is provided, in which an original injection molded part includes a connecting portion, a limiting member is provided on the connecting portion, and the limiting member includes an overlapping portion overlapping with the connecting portion in a thickness direction of the connecting portion; on the basis of the original injection molded part, the thickness of the overlapping portion is reduced and / or part of the overlapping portion is removed.

[0066] This embodiment is aimed at the connection part in the original injection molded part. The connection part refers to the position where the injection molded part is connected and assembled when it is assembled. For example, a common shell includes an upper cover and a lower cover. The part where the upper cover and the lower cover are connected to each other is the connection part. In order to ensure the positioning of the connection part during connection, the connection part is provided with a limiter. The limiter can be a stopper, a stopper and other structures, such as a boss structure and a groove structure that cooperate with each other, and a plug-in slot and a stopper that cooperate with each other. These limiters usually have an overlap portion that overlaps with the connection part in the thickness direction of the connection part. These limiters can cooperate with each other to reduce the problem of step difference and gap.

[0067] After the injection molded parts are designed, actual production tests can be carried out to observe the quality of the injection molded parts. The presence of the upper limit piece on the connection part causes the injection molded parts to have areas where the glue position is excessively thick and thin, which will produce thickness marks during injection molding. In order to eliminate the thickness marks, this embodiment reduces the thickness of the overlapping part or removes part of the overlapping part on the basis of the original injection molded part. Since the overlapping part of the limit piece overlaps with the connection part, the thickness of this part is usually thicker as a whole, which is easy to produce thickness marks. Adjusting this part can directly affect the formation of thickness marks. The specific adjustment method includes reducing the thickness of the overlapping part and removing part of the overlapping part. The two methods can be carried out independently or simultaneously, that is, only the thickness of the overlapping part can be reduced without removing part of the overlapping part, or only part of the overlapping part can be removed without reducing the thickness of the overlapping part, or both the thickness of the overlapping part can be reduced and part of the overlapping part can be removed. The reasons for the thickness mark of injection molded parts include that the thick-walled and thin-walled transition positions affect the flow of materials. The thick-walled part cools more slowly than the thin-walled part, the local temperature difference of the mold is large, and the stress in the transition area will accumulate, which is also the reason for the thickness mark. By reducing the thickness of the overlapped part, on the one hand, the thickness difference can be reduced, and on the other hand, the difference in cooling speed between this part and other parts can be reduced, thereby improving the thickness mark. The more overlapped parts there are and the larger the area, the greater the difference in cooling speed between this part and other parts. Therefore, by removing some overlapped parts, the thickness mark of injection molded parts can also be improved. In addition, since the injection molded part is integrally formed, the limiter itself is integral with the corresponding connecting part. Therefore, reducing the thickness of its overlapped part or removing some overlapped parts will have a very limited effect on the strength of the limiter. The original design scheme can be designed by computer-aided design software such as CAD and SolidWorks. In the specific optimization, it can be optimized in these software.

[0068] See also Figures 3 to 6 In some embodiments of the present application, the limiter includes a first stopper connected to the side of the connecting portion, the overlapping portion includes a first overlapping portion, the first overlapping portion is located at the first stopper, the first overlapping portion overlaps with the connecting portion, and the first stopper also includes an extension portion, the extension portion is connected to the first overlapping portion and extends out of the connecting portion; on the basis of the original injection molded part, the thickness of the first overlapping portion on the side away from the connecting portion and the thickness of the extension portion on the side away from the connecting portion are reduced by the same amount, and the thickness of the extension portion on the side facing the connecting portion is increased.

[0069] Bone stop is a common stopper. It is also a special stopper. Bone stopper usually cooperates with corresponding stopper or plug-in slot to realize the limit of connection between connecting parts. Bone stopper has better limit effect than ordinary stopper.

[0070] In this embodiment, the first bone stopper is connected to the side of the connecting part, so it will overlap with the connecting part, and the overlapping part is the first overlapping part. The first bone stopper also includes an extension part, which is a structure extending from the connecting part. This part of the structure can usually be plugged or snapped with the stopper of another part of the injection molded part. The extension part can adopt a variety of shapes and sizes, depending on the design requirements and functional objectives of the stopper. The existence of the extension part can ensure the stability of the connection between the connecting parts.

[0071] In order to improve the thickness printing, the present embodiment has been optimized accordingly, specifically reducing the thickness of the first overlapping portion, which can reduce the thickness difference and cooling rate difference between this portion and other portions, thereby improving the thickness printing. Since the thickness of the first overlapping portion has been reduced, it is also necessary to reduce the thickness of the side of the extension portion away from the connecting portion, and the reduced thickness is the same as the first overlapping portion, so as to ensure that no new step structure is formed on the side of the first overlapping portion and the extension portion away from the connecting portion. In addition, the extension portion serves as the main limiting force-bearing structure. In order to ensure its strength, the thickness of the side of the extension portion facing the connecting portion is increased. Since there is a connecting portion on this side, no step structure is formed on this side. This not only improves the strength of the extension portion, but also reduces the thickness difference between the extension portion and the connecting portion, further reducing the possibility of thickness printing.

[0072] See also Figures 3 to 6 In some embodiments of the present application, the overlapping portion includes a first rib portion and a second rib portion, the first rib portion and the second rib portion are both connected to the connecting portion, and the first rib portion and the second rib portion are respectively connected to both sides of the first overlapping portion and extend to both sides of the extension portion; on the basis of the original injection molded part, the thickness of the first rib portion facing the second rib is reduced, the thickness of the first rib portion facing away from the second rib is increased, the thickness of the second rib portion facing the first rib is reduced, and the thickness of the second rib portion facing away from the first rib is increased.

[0073] The function of the rib portion is to improve the strength of the limit member. In this embodiment, the limit member includes a first rib portion and a second rib portion connected to the connecting portion. The first rib portion and the second rib portion are respectively connected to both sides of the first overlapping portion and extend to both sides of the extension portion. The existence of the first rib portion and the second rib portion can more reasonably distribute and resist the stress under the action of external force, thereby effectively improving the overall strength of the limit member.

[0074] With respect to the ribs, this embodiment makes two adjustments based on the original injection molded part:

[0075] First, reduce the thickness of the first rib portion on the side facing the second rib, and reduce the thickness of the second rib portion on the side facing the first rib. The first rib portion and the second rib portion are close together, and the cooling of the two will affect each other after injection molding. Generally speaking, the closer the first rib portion and the second rib portion are, the more difficult it is for the heat to diffuse outward, and the slower the cooling speed. Therefore, this embodiment reduces the thickness of the first rib portion on the side facing the second rib, and at the same time reduces the thickness of the second rib portion on the side facing the first rib, so that the interval between the first rib portion and the second rib portion is larger, which is more conducive to cooling and heat dissipation after injection molding, and can reduce the difference in cooling speed between the first rib portion and the second rib portion compared to other parts, thereby further reducing the possibility of thick and thin printing.

[0076] On the other hand, the thickness of the first rib part on the side away from the second rib part is increased, and the thickness of the second rib part on the side away from the first rib is increased. Reducing the thickness of the rib part will weaken its strength. Therefore, the present embodiment also increases the thickness of the first rib part on the side away from the second rib part and the thickness of the second rib part on the side away from the first rib. In this way, the strength of the first rib part and the second rib part can be effectively guaranteed while minimizing the cooling and heat dissipation of the first rib part and the second rib part, thereby ensuring the overall strength of the stopper.

[0077] See also Figures 8 to 11 In some embodiments of the present application, the limiter includes a second bone stopper, the overlapping portion includes a third rib portion and a fourth rib portion located on the second bone stopper, the third rib portion and the fourth rib portion are connected to the side of the connecting portion at intervals, a first stop portion is provided on the side of the third rib portion away from the connecting portion, a second stop portion is provided on the side of the fourth rib portion away from the connecting portion, the first stop portion and the second stop portion are arranged opposite to each other, and an intermediate portion is connected between the first stop portion and the second stop portion, the third rib portion, the fourth rib portion, the first stop portion and the second stop portion form a plug-in groove; on the basis of the original injection molded part, the thickness of the third rib portion facing the fourth rib portion is reduced, the thickness of the fourth rib portion facing the third rib portion is reduced, and the intermediate portion is removed.

[0078] In the second bone stopper, the third rib part and the fourth rib part can ensure its strength on the one hand, and provide attachment points for the first stop part and the second stop part on the other hand. The third rib part, the fourth rib part, the first stop part and the second stop part form a plug-in slot for plugging in the corresponding bone stopper, for example, the aforementioned first bone stopper can be plugged into the plug-in slot. The thickness of the third rib part facing the fourth rib part is reduced, and the thickness of the fourth rib part facing the third rib part is reduced at the same time, so that the interval between the third rib part and the fourth rib part is larger, which is more conducive to cooling and heat dissipation after injection molding, and the cooling speed difference between the third rib part and the fourth rib part compared with other parts can be reduced, thereby further reducing the possibility of thick and thin marks. In addition, the third rib part, the fourth rib part, the first stop part and the second stop part can form a plug-in slot, so the middle part can be removed, further reducing the volume of the second bone stopper, reducing the thickness difference and the cooling speed difference after injection molding, thereby reducing the possibility of thick and thin marks.

[0079] See also Figures 8 to 11 In some embodiments of the present application, the injection molding optimization method also includes, on the basis of the original injection molded part, improving the texture roughness of the outer surface of the original injection molded part, and the texture roughness of the outer surface is positively correlated with the thickness of the overlapping part. Therefore, this embodiment improves the texture roughness of the outer surface of the original injection molded part on the basis of the original injection molded part, thereby reducing the possibility of thick and thin printing. For example, the outer surface of the original injection molded part is a fine spark pattern VDI18, which can be modified to a rough spark pattern VDI24. For the outer surface of the injection molded part with a gradual rough texture, the texture roughness of each area can be increased accordingly, for example, the original texture of VDI18 is modified to the texture of VDI21, and the original texture of VDI21 is modified to the texture of VDI24. It should be noted that since the texture on the surface of the injection molded part is generated by the mold, it is usually necessary to modify the texture roughness of the mold accordingly to achieve the effect of changing the texture roughness of the outer surface of the injection molded part. By increasing the roughness of the texture on the outer surface, on the one hand, it is possible to cover the thickness prints, thereby reducing the possibility of thickness prints, especially for slight thickness prints. More importantly, the outer surface adopts a higher texture roughness. During the injection molding process, the molten plastic is injected into the cool mold cavity. During the molding process of the outer surface of the mold, the rougher texture will increase the venting gaps and venting grooves. The internal stress and extrusion pressure in the thickness transition area are released through the venting gaps and venting grooves, which greatly reduces the thickness prints in the thickness transition area.

[0080] The thicker the overlapped part is, the easier it is to form a thickness mark. Therefore, the thicker the overlapped part is, the more it is necessary to further improve the grain roughness of the outer surface of the injection molded part, that is, the grain roughness of the outer surface is positively correlated with the thickness of the overlapped part. For example, for an injection molded part with an overlapped part thickness of 0.6mm, the VDI value of its grain is greater than or equal to 24, while for an injection molded part with an overlapped part thickness of 0.8mm, the VDI value of its grain is greater than or equal to 26.

[0081] Similarly, in some embodiments of the present application, the injection molding optimization method also includes, based on the original design scheme, improving the texture roughness of the inner surface of the injection molded part, and the texture roughness of the inner surface is positively correlated with the thickness of the overlapped part. The inner surface of the injection molded part is usually light-saving treatment. Although the inner surface of the injection molded part is on the inner side of the injection molded part, its texture roughness will also affect the thickness print on the surface of the injection molded part. During the injection molding process, the molten plastic is injected into the cool mold cavity. During the molding process of the inner surface of the mold, the rougher texture will increase the exhaust gap and exhaust groove. The internal stress and extrusion force in the thickness transition area are released through the exhaust gap and the exhaust groove, which greatly reduces the thickness print in the thickness transition area. Therefore, this embodiment also improves the texture roughness of the inner surface of the injection molded part, thereby further optimizing the thickness print of the injection molded part. For example, the original light-saving treatment can be modified to a surface texture of VDI27. Because the inner surface usually does not need to consider the appearance, the texture roughness of the inner surface can be made greater than the texture roughness of the surface, so that it can further reduce the possibility of the occurrence of thickness prints.

[0082] In some embodiments of the present application, the injection molding optimization method also includes, based on the original design, increasing the draft angle of the outer surface of the original injection molded part. After the texture roughness of the outer surface of the injection molded part is changed, for example, to prevent the appearance of the injection molded part from being scratched during demolding, the draft angle needs to be increased accordingly. For example, when the outer surface of the injection molded part is changed from a fine spark pattern VDI18 to a rough spark pattern VDI24, the draft angle needs to be changed from 1.5° to 3° accordingly.

[0083] See also Fig.14 and Fig.15 In some embodiments of the present application, the injection molding optimization method also includes, based on the original design, adding an exhaust port to the parting surface. The parting surface refers to the part where the front mold and the back mold are in contact when the mold is closed. It is not only the reference surface for mold design, but also the boundary line for plastic part molding. During the injection molding process, the parting surface allows the plastic to enter the mold cavity from the injection machine nozzle, and allows the finished product to be smoothly ejected from the mold after molding. Fig.14 The surface shown in A Fig.15The surface shown in B is the parting surface, which is set to allow the internal stress and extrusion pressure in the thickness transition area to be released through the exhaust gap and the exhaust groove, which effectively reduces the thickness mark in the thickness transition area.

[0084] See also Fig.16 and Fig.17 In some embodiments of the present application, the injection molding optimization method also includes, based on the original design, adding an exhaust port next to the glue inlet of the rear mold. The rear mold, also known as the movable mold, is the movable part of the injection mold. During the injection molding process, the rear mold will open and close so that the molded injection molded part can be removed smoothly after the injection molding is completed. Specifically, adding an exhaust port next to the glue inlet of the rear mold may include the following: Fig.16 The C position and Fig.17 At the D position in the figure, the internal stress and extrusion pressure in the thickness transition area can be released through the exhaust gap and the exhaust groove, which effectively reduces the thickness print in the thickness transition area.

[0085] In some embodiments of the present application, the injection molding optimization method also includes using a duckbill-shaped glue inlet. The duckbill-shaped glue inlet is a flat glue inlet. The duckbill-shaped glue inlet design helps the plastic melt enter the mold cavity at a faster speed, ensuring that the cavity can be quickly and evenly filled, and the molten plastic flows into the mold cavity more evenly. The extrusion pressure and internal stress of each area with excessive thickness can be evenly distributed, so that it is easier to eliminate them together, improving the thickness print caused by uneven distribution of extrusion pressure and internal stress. In addition, you can also choose a material with good fluidity as the injection material. For example, PC+ABS has better fluidity than PC material, and the thickness print can also be effectively improved by the same token.

[0086] Based on the above injection molding optimization method, the present application also provides an injection molded part, which is optimized by the above injection molding optimization method, and can effectively improve the thickness of the injection molded part on the basis of the original injection molded part. Figure 18-Figure 20 This is a picture of the original injection molded part. It can be seen from the picture that there is an obvious thickness mark at the connection part, which seriously affects the appearance of the injection molded part. Figure 21-23 As shown, based on the original injection-molded part, the optimized thickness of the injection-molded part according to the embodiment of the present application is adopted. It is no longer possible to see the thickness mark, and the overall aesthetics of the injection-molded part is greatly improved.

[0087] The present application also provides an injection molded part, the injection molded part comprising:

[0088] Connecting part;

[0089] A limiting member is arranged on the connecting portion, wherein the limiting member includes an overlapping portion overlapping with the connecting portion in a thickness direction of the connecting portion;

[0090] The maximum thickness of the overlapping portion is no more than 60% of the thickness of the connecting portion.

[0091] The connection part refers to the position where the injection molded parts are connected and assembled during assembly. For example, a common shell includes an upper cover and a lower cover. The part where the upper cover and the lower cover are connected to each other is the connection part. In order to ensure the positioning of the connection part during connection, the connection part is provided with a limiter. The limiter can be a stopper, a stopper and other structures, such as a boss structure and a groove structure that match each other, and a plug-in slot and a stopper that match each other. These limiters usually have an overlapped part that overlaps with the connection part in the thickness direction of the connection part. These limiters can cooperate with each other to reduce the problem of step difference and gap. The existence of the limiter on the connection part causes the injection molded part to have an area where the glue position is excessively thick, which will produce a thickness mark during injection molding. In this embodiment, the thickness of the overlapped part is not greater than 60% of the thickness of the connection part, which reduces the difference in cooling speed between the overlapped part and other areas of the connection part, thereby improving the thickness mark.

[0092] In some embodiments of the present application, the limiter includes a first bone stopper connected to the side of the connecting portion, the first bone stopper includes a first overlapping portion and an extended portion, the first overlapping portion overlaps with the connecting portion, the extended portion is connected to the first overlapping portion and extends out of the connecting portion; the side of the extended portion facing away from the connecting portion is flush with the side of the first overlapping portion facing away from the connecting portion, and the side of the extended portion facing the connecting portion at least partially overlaps with the connecting portion.

[0093] The bone stop is a relatively common limiting component. In essence, the bone stop is also a special stop. The bone stop is usually matched with a corresponding stop or a plug-in slot to achieve the limiting of the connection between the connecting parts. Compared with ordinary stoppers, the bone stop has a better limiting effect. The first bone stop is connected to the side of the connecting part, so it will overlap with part of the connecting part. The overlapping part is the first overlapping part. The first bone stop also includes an extension part, which is a structure extending from the connecting part. This part of the structure can usually be plugged or snapped with the limiting component of another part of the injection molded part. The extension part can adopt a variety of shapes and sizes, depending on the design requirements and functional objectives of the limiting component. The existence of the extension part can ensure the stability of the connection between the connecting parts.

[0094] See also Figures 3 to 6In this embodiment, the side of the extension away from the connection part is flush with the side of the first overlap part away from the connection part, ensuring the integrity and smooth transition of the extension part and the first overlap part, and ensuring that no new step structure is formed on the side of the first overlap part and the extension part away from the connection part. However, since this embodiment requires that the maximum thickness of the first overlap part be controlled to no more than 60% of the thickness of the connection part, and the extension part and the side of the first overlap part away from the connection part are flush, it is necessary to control the thickness of the extension part on this side, and the extension part is a key force-bearing component for the connection and positioning of the injection molded part. In order to ensure that it has sufficient strength, in this embodiment, the side of the extension part facing the connection part at least partially overlaps with the connection part. In this way, the outer edge part is not only connected to the first overlap part as a whole, but also directly connected to the connection part as a whole. The overall thickness of the outer edge part is guaranteed, thereby ensuring the mechanical strength of the extension part. More importantly, this method can also reduce the possibility of thick and thin printing.

[0095] See also Figures 3 to 6 In some embodiments of the present application, the overlapping portion further includes a first rib portion and a second rib portion, the first rib portion and the second rib portion are both connected to the connecting portion, and the first rib portion and the second rib portion are respectively connected to both sides of the first overlapping portion and extend to both sides of the extension portion; the first rib portion and the second rib portion satisfy: D≥T+0.1mm, wherein D represents the spacing between the first rib portion and the second rib portion, and T represents the maximum thickness of the first rib portion and the second rib portion.

[0096] The function of the rib portion is to improve the strength of the limiter. The overlapping portion includes a first rib portion and a second rib portion connected to the connecting portion. The first rib portion and the second rib portion are respectively connected to both sides of the first overlapping portion and extend to both sides of the extended portion. The existence of the first rib portion and the second rib portion can more reasonably distribute and resist the stress under the action of external force, thereby effectively improving the overall strength of the limiter.

[0097] Since the thickness of the rib part is relatively thick, it is the factor that most easily affects the appearance of thickness prints. In addition to controlling its thickness, the spacing between the first rib part and the second rib part is also controlled in this embodiment. This is because the thickness of the rib part is usually the thickest and the cooling speed is also the slowest. If the first rib part and the second rib part are too close to each other, the heat dissipation during the cooling process of the two will affect each other, and then further slow down the cooling speed of the two, thereby increasing the possibility of thick wall prints. At the same time, the greater the thickness of the first rib part and the second rib part, the larger the heat dissipation affected area. It has been found through experiments that when the spacing between the first rib part and the second rib part minus the maximum thickness of the first rib part and the second rib part is above 0.1mm, the heat dissipation of the first rib part and the second rib part will basically not affect each other, and thickness prints will not appear.

[0098] See also Figures 8 to 11The limiting member includes a second bone stop, the overlapping portion includes a third rib portion and a fourth rib portion located on the second bone stop, the third rib portion and the fourth rib portion are spaced and connected to the side of the connecting portion, a first stop portion is provided on the side of the third rib portion away from the connecting portion, a second stop portion is provided on the side of the fourth rib portion away from the connecting portion, the first stop portion and the second stop portion are arranged opposite to each other, and there is a gap between the first stop portion and the second stop portion.

[0099] In the second bone stop, the third rib part and the fourth rib part can ensure its strength on the one hand, and provide attachment points for the first stop part and the second stop part on the other hand. The third rib part, the fourth rib part, the first stop part and the second stop part form a plug-in groove for plugging in the corresponding bone stop. For example, the aforementioned first bone stop can be plugged into the plug-in groove. Fig.13 As shown, in general, the stopper and the rib part are surrounded by a closed structure. In this embodiment, the first stopper and the second stopper are arranged opposite to each other, and there is a gap between the first stopper and the second stopper. In this way, the second rib can be reduced to the greatest extent while ensuring that it has a plug-in slot for plug-in, thereby reducing the possibility of thick and thin marks.

[0100] In some embodiments of the present application, the thickness of the overlapped portion and the grain roughness of the outer surface of the injection molded part satisfy: X≥22+20*(T-0.6), wherein D represents the maximum thickness of the overlapped portion, and X represents the VDI value of the outer surface of the injection molded part. The outer surface adopts a higher grain roughness. During the injection molding process, the molten plastic is injected into the cool mold cavity. During the molding process of the outer surface of the mold, the rougher grain will increase the number of exhaust gaps and exhaust grooves. The internal stress and extrusion pressure in the thickness transition area are released through the exhaust gap and the exhaust groove, which greatly reduces the thickness mark in the thickness transition area. The thicker the thickness of the overlapped portion, the easier the thickness mark is to form. Therefore, the thicker the thickness of the overlapped portion, the more it is necessary to further improve the grain roughness of the outer surface of the injection molded part, that is, the grain roughness of the outer surface is positively correlated with the thickness of the overlapped portion. Through experiments and formula fitting based on the test data, it can be obtained that when the thickness of the overlapping part and the texture roughness of the outer surface of the injection molded part meet: X≥22+20*(T-0.6), the occurrence of thick and thin prints can be prevented.

[0101] The following are some embodiments of the present application.

[0102]

[0103] Among them, the products produced in Examples 1-5 are all power adapter shells, and their structures can refer to Figures 1 to 11. The specific specifications of Examples 1-5 are different, among which the thickness of the connection part refers to the thickness of the upper and lower shell edges, which is equivalent to the shell thickness. The thickness of the rib part refers to the thickness of the first rib part and the second rib part, and the thickness of the two is consistent. Because the thickness of the rib part is the thickest position of the overlapping part of the limiter, this thickness can be used to represent the maximum thickness of the overlapping part. The outer surface texture roughness represents the roughness of the outer surface of the shell, and is measured by VDI value.

[0104] like Figures 24 to 28 , are product photos of Example 1 to Example 5, and the thickness and thinness of the prints were tested under the following conditions:

[0105] Testing environment light source: 100W cold white fluorescent lamp, the light source is 500-550mm away from the surface of the object to be tested (illuminance reaches 600-800Lux) and the distance between the surface of the object to be tested and the eyes is 30-40cm;

[0106] Angle between sight line and surface of inspected object: 45±15;

[0107] Inspection time: ≥5-10s;

[0108] Inspector's vision: naked or corrected vision above 1.0 and no color blindness.

[0109] Finally, the test shows that none of the above embodiments 1-5 has thickness marks, and the test results are qualified.

[0110] According to the embodiments in the above table, it can be seen that the thickness of the ribs is less than or equal to 0.6 times the thickness of the connection. The thickness of the ribs and the spacing between the ribs are fitted by a formula, and it can be obtained that: D = T + 0.1mm, where D represents the spacing between the first rib and the second rib, and T represents the maximum thickness of the first rib and the second rib. Because the greater the distance between the first rib and the second rib, the less likely it is to have a thick and thin mark, therefore, according to the above embodiment, it can be obtained that: D ≥ T + 0.1mm. The thickness of the ribs and the spacing of the roughness of the outer surface texture are fitted by a formula, and it can be obtained that X = 22 + 20 * (T-0.6), where D represents the maximum thickness of the overlapped portion, and X represents the VDI value of the outer surface of the injection molded part. Because the greater the VDI value of the outer surface texture, the less likely it is to have a thick and thin mark, therefore, according to the above embodiment, it can be obtained that: X ≥ 22 + 20 * (T-0.6).

[0111] The above are only preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. An injection molding optimization method for improving the thickness of an original injection molded part, characterized in that: The injection molding optimization method comprises: Providing an original design scheme, wherein the original injection molded part in the original design scheme includes a connecting portion, the connecting portion is provided with a limiting member, and the limiting member includes an overlapping portion overlapping with the connecting portion in a thickness direction of the connecting portion; On the basis of the original injection molded part, the thickness of the overlapping portion is reduced and / or part of the overlapping portion is removed.

2. The injection molding optimization method according to claim 1, characterized in that: The stopper includes a first bone stop connected to a side of the connecting portion, the overlapping portion includes a first overlapping portion, the first overlapping portion is located at the first bone stop, the first overlapping portion overlaps with the connecting portion, and the first bone stop also includes an extension portion, the extension portion is connected to the first overlapping portion and extends out of the connecting portion; On the basis of the original injection molded part, the thickness of the first overlapping portion on the side away from the connecting portion and the thickness of the extension portion on the side away from the connecting portion are reduced by the same amount, and the thickness of the extension portion on the side facing the connecting portion is increased.

3. The injection molding optimization method according to claim 2, characterized in that: The overlap portion further includes a first rib portion and a second rib portion, the first rib portion and the second rib portion are both connected to the connecting portion, and the first rib portion and the second rib portion are respectively located on both sides of the first overlap portion and extend to both sides of the extension portion; On the basis of the original injection molded part, the thickness of the first rib portion facing the second rib portion is reduced, the thickness of the first rib portion facing away from the second rib is increased, the thickness of the second rib portion facing the first rib is reduced, and the thickness of the second rib portion facing away from the first rib is increased.

4. The injection molding optimization method according to claim 1, characterized in that: The limiting member includes a second bone stopper, the overlapping portion includes a third rib portion and a fourth rib portion located on the second bone stopper, the third rib portion and the fourth rib portion are connected to the side of the connecting portion at intervals, a first stop portion is provided on a side of the third rib portion away from the connecting portion, a second stop portion is provided on a side of the fourth rib portion away from the connecting portion, the first stop portion and the second stop portion are arranged facing each other, and an intermediate portion is connected between the first stop portion and the second stop portion, and the third rib portion, the fourth rib portion, the first stop portion and the second stop portion surround a plug-in slot; On the basis of the original injection molded part, the thickness of the third rib portion facing the fourth rib is reduced, the thickness of the fourth rib portion facing the third rib is reduced, and the middle portion is removed.

5. The injection molding optimization method according to claim 1, characterized in that: The injection molding optimization method further includes, based on the original injection molded part, improving the texture roughness of the outer surface of the injection molded part, wherein the texture roughness of the outer surface is positively correlated with the thickness of the overlapped portion; And / or, the injection molding optimization method further includes, based on the original design scheme, improving the texture roughness of the inner surface of the injection molded part, and the texture roughness of the inner surface is positively correlated with the thickness of the overlapping portion.

6. The injection molding optimization method according to claim 5, characterized in that: The injection molding optimization method also includes, based on the original design scheme, increasing the outer surface draft angle of the original injection molded part.

7. The injection molding optimization method according to claim 1, characterized in that: The injection molding optimization method further includes, based on the original design scheme, adding an exhaust port on the parting surface; And / or, add an exhaust port next to the glue inlet of the rear mold.

8. The injection molding optimization method according to claim 1, characterized in that: The injection molding optimization method also includes adopting a duckbill type glue inlet.

9. An injection molded part, characterized in that: The injection molded part is optimized using the injection molding optimization method described in any one of claims 1 to 9.

10. An injection molded part, characterized in that: The injection molded part comprises: Connecting part; A stopper, arranged on the connecting portion, wherein the stopper comprises an overlapping portion overlapping with the connecting portion in a thickness direction of the connecting portion; Wherein, the thickness of the overlapping portion is not greater than 60% of the thickness of the connecting portion.

11. The injection molded part according to claim 10, characterized in that: The stopper includes a first bone stop connected to the side of the connecting portion, the overlapping portion includes a first overlapping portion, the first overlapping portion is located at the first bone stop, the first overlapping portion overlaps with the connecting portion, the first bone stop also includes a first overlapping portion, and the extension portion is connected to the first overlapping portion and extends out of the connecting portion; A side of the extension portion facing away from the connecting portion is flush with a side of the first overlapping portion facing away from the connecting portion, and a side of the extension portion facing the connecting portion at least partially overlaps with the connecting portion.

12. The injection molded part according to claim 11, characterized in that The overlap portion includes a first rib portion and a second rib portion, the first rib portion and the second rib portion are both connected to the connection portion, and the first rib portion and the second rib portion are respectively connected to two sides of the first overlap portion and extend to two sides of the extension portion; The first rib portion and the second rib portion satisfy: D≥T+0.1 mm, wherein D represents the distance between the first rib portion and the second rib portion, and T represents the maximum thickness of the first rib portion and the second rib portion.

13. The injection molded part according to claim 12, characterized in that The limiting component includes a second bone stop, and the overlapping portion includes a third rib portion and a fourth rib portion located on the second bone stop, the third rib portion and the fourth rib portion are spaced apart and connected to the side of the connecting portion, a first stop portion is provided on the side of the third rib portion away from the connecting portion, and a second stop portion is provided on the side of the fourth rib portion away from the connecting portion, the first stop portion and the second stop portion are arranged opposite to each other, and there is a gap between the first stop portion and the second stop portion.

14. The injection molded part according to claim 11, 12 or 13, characterized in that: The thickness of the overlapping portion and the texture roughness of the outer surface of the injection molded part satisfy: X≥22+20*(T-0.6), wherein D represents the maximum thickness of the overlapping portion, and X represents the VDI value of the outer surface of the injection molded part.

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