Structure for effectively preventing shrinkage printing of corresponding A surface of PP material doghouse structure
By setting hollow kennel structure, reinforcement ribs and notches on the back of the PP plastic parts, the shrinking problem arising from the cooling process of the kennel structure is solved, effectively preventing the A-side shrinking printing, improving yield and reducing costs.
Patent Information
- Application Number
- CN202421754644.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-24
- Publication Date
- 2025-06-17
- Estimated Expiration
- 2034-07-24
AI Technical Summary
The shrinking pulling force generated by the doghouse structure of PP plastic parts during cooling causes the A-side shrinking printing, affecting the appearance aesthetics.
A hollow kennel structure is provided on the back of the PP plastic parts, and reinforcement ribs are provided between the sides of the kennel structure and the back of the PP plastic parts to increase gaps to reduce pulling force.
By reducing the wall thickness of the roots of the kennel structure, increasing the cooling rate, arranging reinforcement ribs and notches, reducing shrinkage stress, effectively preventing A-side shrinkage printing, improving yield and saving costs.
Smart Images
Figure CN222988099U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of automotive exterior parts, in particular to a structure that can effectively prevent shrink marks on the A surface corresponding to the doghouse structure of PP material. Background Art
[0002] PP plastic parts are injection molded from PP material. Due to the thermal expansion and contraction characteristics of plastics and the Doghouse structure provided for product assembly itself, the Doghouse, also known as the doghouse structure, will cause concave pulling at the position of the Doghouse on the front side (i.e., the A surface) of the PP plastic part, that is, shrink marks. The formation of shrink marks will greatly affect the aesthetic degree of the overall appearance of the PP plastic part. Therefore, it is necessary to improve the product structure for the above-mentioned shrink mark appearance defects. Summary of the Invention
[0003] The technical problem to be solved by the utility model is to provide a structure that can effectively prevent shrink marks on the A surface corresponding to the doghouse structure of PP material, which can directly eliminate the common appearance defect of shrink marks on the front side of the doghouse structure, greatly improve the qualified rate, and save costs.
[0004] The technical solution adopted by the utility model to solve its technical problems is: to provide a structure that can effectively prevent shrink marks on the A surface corresponding to the doghouse structure of PP material, including a PP plastic part and a doghouse structure. The doghouse structure is arranged on the back surface of the PP plastic part, and the inside of the doghouse structure is hollowed out to form a chamber. At least one reinforcing rib is arranged between the side of the doghouse structure and the back surface of the PP plastic part, and at least one notch is opened at the connection between the doghouse structure and the PP plastic part.
[0005] As a supplement to the technical solution of the utility model, the wall thickness of the PP plastic part is 3.2 mm.
[0006] As a supplement to the technical solution of the utility model, the height of the notch is 2.8 mm.
[0007] As a supplement to the technical solution of the utility model, the wall thickness of the reinforcing rib is 0.8 mm.
[0008] As a supplement to the technical solution of the utility model, a reinforcing rib is arranged every 6 - 7 mm between the side of the doghouse structure and the back surface of the PP plastic part.
[0009] As a supplement to the technical solution of the utility model, the wall thickness at the root of the lower end of the doghouse structure is 0.8 mm.
[0010] As a supplement to the technical solution of the utility model, a buckle is arranged at the top of the doghouse structure.
[0011] As a supplement to the technical solution described in the present utility model, a rib in an inverted T shape is provided at the inner wall of the upper part of the chamber. One end of the rib is connected to the PP plastic part, and the other end of the rib is connected to the inner side wall of the chamber.
[0012] As a supplement to the technical solution described in the present utility model, the PP plastic part has a bent long strip structure. An R corner structure is provided at the upper part of the PP plastic part, and one end of the rib is connected to the R corner structure.
[0013] As a supplement to the technical solution described in the present utility model, the width of the contact surface at the root of the rib is 2 mm.
[0014] Beneficial effects: The present utility model relates to a structure that can effectively prevent the shrinkage printing on the A surface corresponding to the doghouse structure of PP material. By reducing the wall thickness at the root of the doghouse structure, the cooling rate at the root is increased, and then reinforcing ribs are arranged to ensure the strength of the doghouse structure. A notch is opened at the connection between the doghouse structure and the PP plastic part. Through the added notch structure, the pulling force generated during the shrinkage of the root of the doghouse structure is reduced, the problem of shrinkage marks on the A surface is improved, the appearance defect of shrinkage printing on the front surface commonly generated by the doghouse structure can be directly eliminated, the yield rate is greatly improved, and the cost is saved. Description of the Drawings
[0015] Figure 1 is the front view of the present utility model;
[0016] Figure 2 is the rear view of the present utility model;
[0017] Figure 3 is the top view of the present utility model.
[0018] Illustration: 100, PP plastic part; 200, doghouse structure; 300, reinforcing rib; 400, notch; 500, chamber; 600, rib; 700, buckle; 800, R corner structure. Detailed Embodiments
[0019] The following further elaborates the present utility model in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present utility model and not to limit the scope of the present utility model. In addition, it should be understood that after reading the content taught by the present utility model, those skilled in the art can make various changes or modifications to the present utility model, and these equivalent forms also fall within the scope defined by the appended claims of this application.
[0020] During the injection molding process, due to the thermal expansion and contraction characteristics of plastics, when cooling occurs, the shrinkage pulling force generated by the Doghouse will cause the A surface corresponding to its root to be pulled concave, forming shrinkage printing, especially more obvious for PP material.
[0021] AsFigures 1-3 As shown, an embodiment of the present utility model relates to a structure that can effectively prevent the surface shrinkage of the A surface corresponding to the doghouse structure made of PP material, including a PP plastic part 100 and a doghouse structure 200. The doghouse structure 200 is arranged on the back surface of the PP plastic part 100. The wall thickness of the PP plastic part 100 is 3.2 mm, and the wall thickness at the root of the lower end of the doghouse structure 200 is 0.8 mm. By reducing the wall thickness at the root of the doghouse structure 200, the cooling rate at the root is increased, and the plastic at the root freezes before it has time to shrink, or the freezing time becomes shorter rapidly, reducing the shrinkage stress at the root, thereby improving the problem of surface shrinkage of the A surface corresponding to the root of the Doghouse 200. A cavity 500 is formed by hollowing out the interior of the doghouse structure 200. At least one reinforcing rib 300 is arranged between the side of the doghouse structure 200 and the back surface of the PP plastic part 100 to ensure the strength of the doghouse structure 200 by arranging the reinforcing rib 300. At least one notch 400 is opened at the connection between the doghouse structure 200 and the PP plastic part 100. By adding the notch 400 structure, the pulling force generated during the shrinkage of the root of the doghouse structure 200 is reduced, improving the problem of surface shrink marks. At the same time, the range of the transverse rib perpendicular to the material flow direction is greatly reduced. The transverse rib of the Doghouse interfering with the material flow will also make the shrinkage worse.
[0022] In this embodiment, the number of notches 400 is determined according to the size specifications of the connection between the doghouse structure 200 and the PP plastic part 100. Refer to Figure 1 and 2 As shown, since the doghouse structure 200 is connected to the bottom and side of the back surface of the PP plastic part 100, the number is relatively more, which is three. One notch 400 is arranged between the bottom of the back surface of the doghouse structure 200 and the PP plastic part 100, and two notches 400 are arranged between the side of the back surface of the doghouse structure 200 and the PP plastic part 100. The height of the notch 400 is 2.8 mm, and the notch 400 is in a strip-shaped structure.
[0023] Refer to Figure 1 As shown, a reinforcing rib 300 is arranged every 6 - 7 mm between the side of the doghouse structure 200 and the back surface of the PP plastic part 100; the wall thickness of the reinforcing rib 300 is 0.8 mm.
[0024] In this embodiment, a buckle 700 is arranged at the top of the doghouse structure 200 to fix and install the PP plastic part 100 through the buckle 700. This is one way of fixing, but it is not limited to this. Other ways such as fixing with fasteners can also be used.
[0025] Further, a rib 600 for strengthening the upper structure is provided at the inner wall of the upper part of the chamber 500. The rib 600 is in an inverted T shape. The shrinkage deformation of the doghouse structure 200 is reduced by the rib 600. One end of the rib 600 is connected to the PP plastic part 100, and the other end of the rib 600 is connected to the inner side wall of the chamber 500. Such an arrangement of the rib 600 can better cover the upper part of the chamber 500, stabilize the overall structure, and enhance the structural strength. The width of the contact surface at the root of the rib 600 is 2 mm.
[0026] Still further, referring to Figure 1 As shown, the PP plastic part 100 has a bent long strip structure. An R corner structure 800 is provided at the upper part of the PP plastic part 100. The structural strength and stability of the PP plastic part 100 are improved as a whole through the R corner structure 800. One end of the rib 600 is connected to the R corner structure 800, and the cooperation effect of the R corner structure 800 and the rib 600 is better, and the stability is also better.
[0027] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by orientation words such as "front, back, up, down, left, right", "horizontal, vertical, perpendicular, horizontal" and "top, bottom", etc. is usually based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description. Without contrary description, these orientation words do not indicate and imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation on the protection scope of the present invention; the orientation words "inside, outside" refer to the inside and outside relative to the contour of each component itself.
[0028] For the convenience of description, spatial relative terms such as "above...", "above...", "on the upper surface of...", "above" can be used here to describe the spatial positional relationship between a device or feature shown in the figure and other devices or features. It should be understood that the spatial relative terms are intended to include different orientations in use or operation in addition to the orientation described in the figure for the device. For example, if the device in the drawing is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures" afterwards. Thus, the exemplary term "above..." can include two orientations of "above..." and "below...". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and corresponding explanations are made for the spatial relative descriptions used here.
[0029] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. Without additional statements, the above terms have no special meanings, so they should not be construed as limitations on the protection scope of the present utility model.
[0030] The above has introduced in detail a structure for effectively preventing the shrinkage printing on the A surface of the PP material dog house structure provided by the present application. Specific examples are used in this article to elaborate on the principle and implementation manner of the present application. The description of the above embodiments is only used to help understand the method and its core idea of the present application; at the same time, for those of ordinary skill in the art, according to the idea of the present application, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation on the present application.
Claims
1. A structure for effectively preventing the shrinkage of the A side of a PP material doghouse structure, comprising a PP plastic part (100) and a doghouse structure (200), characterized in that: A doghouse structure (200) is arranged on the back of the PP plastic part (100), the interior of the doghouse structure (200) is hollowed out to form a chamber (500), at least one reinforcing rib (300) is arranged between the side of the doghouse structure (200) and the back of the PP plastic part (100), and at least one notch (400) is provided at the connection between the doghouse structure (200) and the PP plastic part (100).
2. According to claim 1, a structure for effectively preventing the shrinkage of the A side of the PP material doghouse structure is characterized by: The wall thickness of the PP plastic part (100) is 3.2 mm.
3. According to claim 1, a structure for effectively preventing the shrinkage of the A side of the PP material doghouse structure is characterized by: The height of the notch (400) is 2.8 mm.
4. According to claim 1, a structure for effectively preventing the shrinkage of the A side of the PP material doghouse structure is characterized by: The wall thickness of the reinforcing rib (300) is 0.8 mm.
5. According to claim 1, a structure for effectively preventing the shrinkage of the A side of the PP material doghouse structure is characterized by: A reinforcing rib (300) is provided between the side of the doghouse structure (200) and the back of the PP plastic part (100) at intervals of 6 to 7 mm.
6. The structure for effectively preventing the shrinkage of the A side of the PP material doghouse structure according to claim 1, characterized in that: The wall thickness of the lower root of the doghouse structure (200) is 0.8 mm.
7. The structure for effectively preventing the shrinkage of the A side of the PP material doghouse structure according to claim 1, characterized in that: A buckle (700) is provided on the top of the doghouse structure (200).
8. The structure for effectively preventing the shrinkage of the A side of the PP material doghouse structure according to claim 1, characterized in that: An inverted T-shaped rib (600) is provided on the inner wall of the upper part of the chamber (500), one end of the rib (600) is connected to the PP plastic part (100), and the other end of the rib (600) is connected to the inner wall of the chamber (500).
9. The structure for effectively preventing the shrinkage of the A side of the PP material doghouse structure according to claim 8, characterized in that: The PP plastic part (100) is in the form of a bent long strip structure. An R-angle structure (800) is provided on the upper part of the PP plastic part (100). One end of the rib (600) is connected to the R-angle structure (800).
10. The structure for effectively preventing the shrinkage of the A side of the PP material doghouse structure according to claim 8, characterized in that: The width of the contact surface at the root of the rib (600) is 2 mm.