Commercial vehicle outer decorating part of hollow structure and mold

Abstract

The utility model discloses a hollow structure commercial vehicle outer decorating part and a mold, and relates to the technical field of automobile parts, the hollow structure commercial vehicle outer decorating part comprises a panel, the back surface of the panel is provided with a raised reinforcing part, the reinforcing part is internally provided with a hollow cavity, the cavity is communicated with the outside, and when a product is formed, the hollow reinforcing part is provided with a plurality of through holes. And the cavity is filled with filling gas. According to the utility model, the production efficiency and the qualified rate are improved, and the production cost is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of automobile parts, in particular to a commercial vehicle exterior decoration part with a hollow structure and a mold. Background Art

[0002] Existing commercial vehicle PDCPD material exterior trim parts are commonly molded using RIM molding for single-layer structures or RIM molding of inner and outer panels separately and then bonding them together to form a hollow structure. Common problems include:

[0003] 1. Single-layer exterior parts molded by RIM cannot avoid sink marks on the outer surface, material shortages and bubbles on the back reinforcement ribs. Due to the low rigidity of single-layer products, deformation caused by residual internal stress during molding is unavoidable, making it difficult to control the dimensional accuracy of the parts.

[0004] 2. RIM molded double-layer bonded hollow structure exterior parts have low production efficiency, unstable bonding process, difficult bonding performance testing, and are prone to defective products. In addition, because bonding stress is inevitable, it will cause secondary deformation, making it difficult to control the size of the parts. Utility Model Content

[0005] In view of the defects in the prior art, the purpose of the present invention is to provide a hollow structure commercial vehicle exterior decoration part and mold, which improves production efficiency and qualification rate and reduces production costs.

[0006] In order to achieve the above purpose, the technical solution adopted by the utility model is: a hollow structure commercial vehicle exterior decoration part, including a panel, a raised reinforcement part is provided on the back of the panel, a hollow cavity is provided inside the reinforcement part, the cavity is connected to the outside world, and when the product is formed, the cavity is filled with filling gas.

[0007] A further improvement is that the panel and the reinforcement are an integrated structure and are both made of PDCPD material.

[0008] A further improvement is that the filling gas is nitrogen.

[0009] A further improvement is that the reinforcement portion is provided with a plurality of holes.

[0010] A further improvement is that the reinforcement portion is provided with a plurality of fixing structures.

[0011] A further improvement is that the fixing structure is a pre-embedded nut.

[0012] A further improvement is that the upper edge of the panel is bent backward to form a first flange, and the lower edge of the panel is bent backward to form a second flange.

[0013] The utility model also provides a mold for manufacturing the above-mentioned hollow structure commercial vehicle exterior decoration part, comprising a front half mold and a rear half mold, wherein the front half mold and the rear half mold are combined to form a sealed cavity, the outer side surface of the front half mold is provided with a first connecting seat, and the first connecting seat is provided with a feed port, which is connected to the cavity through a feed channel;

[0014] The cavity is provided with an air inlet;

[0015] A second connecting seat is provided on the outer side surface of the rear half mold, and an air valve is provided on the second connecting seat. The air inlet end of the air valve is connected to the high-pressure air source, and the air outlet end of the air valve is connected to the air inlet through the air guide pipe.

[0016] A further improvement is that the cavity is provided with an exhaust groove.

[0017] A further improvement is that the first connecting seat and the second connecting seat are arranged opposite to each other.

[0018] The beneficial effects of the present invention are:

[0019] 1. This utility model uses a gas-assisted RIM molding process to produce one-piece (no bonding required) hollow structural exterior parts. Compared with double-layer bonding structures, production efficiency is significantly improved, and the single-piece production cycle is increased by 50%-70%;

[0020] 2. The utility model eliminates the risk of unqualified parts flowing out due to bonding failure, thereby increasing the product qualification rate by 20%-30%;

[0021] 3. Since high-pressure nitrogen is filled in the middle of the part during molding, the shrinkage defects during the molding process are left on the B side (reinforcement side) of the product, which significantly improves the quality of the A side (panel side) of the part. This greatly improves the quality of the A side of the part, eliminating the need to repair defects on the product surface before painting.

[0022] 4. Since the present invention does not require the use of glue, the cost of the product assembly is reduced by 30%-40% compared to the cost of a double-layer adhesive structure;

[0023] 5. Due to the double-layer hollow structure of the present invention, there is no need to design a reinforcing rib structure, and the fixing structure can be designed on the B surface layer. Compared with single-layer structure parts, the appearance of the B surface is greatly improved, making the B surface appearance also very simple;

[0024] 6. Since the utility model is an integrally formed double-layer hollow structure, the rigidity of the part itself is greatly improved, and there is no bonding stress, which greatly improves the product's ability to resist stress deformation and greatly improves the dimensional stability of the part. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a schematic structural diagram of a hollow structure commercial vehicle exterior decoration component in an embodiment of the present utility model;

[0026] Figure 2 for Figure 1 Cross-sectional view along the AA axis;

[0027] Figure 3 This is a schematic structural diagram of the mold in the embodiment of the present utility model;

[0028] Figure 4 This is a structural diagram of the mold from the other side of the embodiment of the present invention;

[0029] Figure 5 This is a front view of the mold in the embodiment of the utility model;

[0030] Figure 6 for Figure 5 Cross-sectional view along the BB direction;

[0031] Figure 7 It is a structural schematic diagram of the rear half mold in an embodiment of the present utility model.

[0032] Reference numerals:

[0033] 1-panel; 11-first flange; 12-second flange;

[0034] 2-reinforcement part; 21-cavity; 22-fixing structure; 23-hole;

[0035] 3-front half mold; 31-first connecting seat; 32-feed port;

[0036] 4-rear half mold; 41-second connecting seat; 42-air valve; 43-air guide pipe; 44-exhaust groove; 45-air inlet;

[0037] 5-Cavity. DETAILED DESCRIPTION

[0038] The embodiments of the present invention are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar numbers throughout represent the same or similar elements or elements with the same or similar functions.

[0039] In the description of the present invention, it should be noted that, for directional words, such as the terms "center", "horizontal (X)", "longitudinal (Y)", "vertical (Z)", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and so on, indicating directions and positional relationships are based on the directions or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and cannot be understood as limiting the specific protection scope of the present invention.

[0040] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features. Therefore, the terms "first" and "second" may explicitly or implicitly refer to one or more of these features. In the description of this utility model, "several" and "a number" mean two or more, unless otherwise specifically defined.

[0041] The following description of the embodiments of the present invention is provided in conjunction with the accompanying drawings to further describe the specific embodiments of the present invention so that the technical solutions and beneficial effects of the present invention are more clearly understood. The following description of the embodiments with reference to the accompanying drawings is for illustrative purposes only and is intended to explain the present invention, but is not to be construed as limiting the present invention.

[0042] See also Figures 1 and 2 As shown, an embodiment of the utility model provides a hollow structure commercial vehicle exterior decoration part, including a panel 1 (the A surface layer of the product, which is the main appearance structure of the product), a raised reinforcement part 2 is provided on the back of the panel 1 (the B surface layer of the product, which mainly plays a reinforcing role), and a hollow cavity 21 is provided inside the reinforcement part 2. The cavity 21 is connected to the outside world, and when the product is formed, the cavity 21 is filled with filling gas. In this embodiment, the filling gas is nitrogen. Specifically, the panel 1 and the reinforcement part 2 are an integrated structure, both made of PDCPD material. The reinforcement part 2 is provided with a number of holes 23. The reinforcement part 2 is provided with a number of fixing structures 22. In this embodiment, the fixing structure 22 is a pre-embedded nut. The upper edge of the panel 1 is bent backward to form a first flange 11, and the lower edge of the panel 1 is bent backward to form a second flange 12.

[0043] See also Figures 3 to 7As shown, the embodiment of the present invention also provides a mold for manufacturing the above-mentioned hollow structure commercial vehicle exterior decoration parts, including a front half mold 3 and a rear half mold 4, and the front half mold 3 and the rear half mold 4 are combined to form a sealed cavity 5, and the front half mold 3 and the rear half mold 4 must use sealing strips to ensure gas sealing. The outer side surface of the front half mold 3 is provided with a first connecting seat 31, and the first connecting seat 31 is provided with a feed port 32. The feed port 32 is connected to the cavity 5 through a feed channel. The injection head of the PDCPD liquid is used to inject the two components A and B into the mixing head according to the set ratio and pressure. The mixing head is used to mix the A liquid and B liquid of the PDCPD and then inject them into the cavity 5 inside the mold through the feed port 32; the cavity 5 is provided with an air inlet 45; specifically, the cavity 5 is also provided with an exhaust groove 44, which is generally provided at the top of the product. The thickness of the groove is generally 0.3mm to 0.7mm, and the width of the exhaust groove should be adjusted according to the size and structural shape of the product, and is finally determined according to the CAE simulation filling process. The outer side of the rear mold half 4 is provided with a second connection seat 41, which is equipped with an air valve 42. The air inlet of the air valve 42 is connected to a high-pressure air source, and the air outlet of the air valve 42 is connected to an air inlet 45 via an air guide tube 43. The air guide tube 43 injects purified high-pressure nitrogen, which needs to be heated to 40°C to 50°C to ensure an orderly reaction of PDCPD. Specifically, the first connection seat 31 and the second connection seat 41 are arranged opposite each other.

[0044] Gas-assisted RIM process description:

[0045] First, the mold must be heated, as in the conventional PDCPD RIM process. There must be a temperature difference between the front and rear molds, with the front mold higher and the rear mold lower, depending on the process characteristics of the raw material. Next, the mold is closed and the raw material is injected. The raw material cannot completely fill the cavity, and is generally injected into 60% to 90% of the cavity volume, depending on the product shape, size, and process conditions. After that, the air valve is controlled to open and high-pressure nitrogen heated to 40 to 50 degrees Celsius is injected. The nitrogen pressure is generally between 10 MPa and 20 MPa. The injection time needs to be precisely controlled. The raw material in the cavity must react for a period of time and the viscosity of the raw material must rise to 1000 CPS before gas injection can begin. After the viscosity reaches 2500 CPS, gas injection must be stopped and a holding pressure of 1 to 2 MPa must be maintained for a certain period of time. Finally, after the product is completely cured, the nitrogen pressure can be released, the mold can be opened, and the part can be removed, completing the process.

[0046] Special process performance requirements for PDCPD raw materials: Since there are certain requirements for the viscosity of the raw materials during gas injection, the A and B raw solutions must be injected into the mold cavity and maintained at a viscosity of 1000CPS to 2500CPS for more than 10 seconds. This requires that the viscosity-time curve of the raw materials be different from that of conventional RIM raw materials, which is also the key to this process.

[0047] Compared with the double-layer bonding structure, the present invention significantly improves production efficiency and increases the single-piece production cycle by 50%-70%; compared with the double-layer bonding structure, the present invention does not have the risk of unqualified parts flowing out due to bonding failure, so the product qualification rate is increased by 20%-30%; compared with the double-layer bonding structure, the present invention does not require the use of glue, so the cost of the product assembly is reduced by 30%-40% compared with the cost of the double-layer bonding structure.

[0048] In the description of the specification, reference to the terms "one embodiment," "preferably," "example," "specific example," or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. The schematic expressions of the above terms in this specification do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any appropriate manner in any one or more embodiments or examples.

[0049] Through the description of the above structure and principle, technical personnel in the relevant technical field should understand that the present invention is not limited to the above specific implementation methods, and improvements and substitutions based on the present invention using the well-known technology in the field all fall within the scope of protection of the present invention and should be defined by the claims.

Claims

1. A hollow structure commercial vehicle exterior decoration part, comprising a panel (1), characterized in that: The back of the panel (1) is provided with a raised reinforcement portion (2), the interior of the reinforcement portion (2) is provided with a hollow cavity (21), the cavity (21) is communicated with the outside, and when the product is formed, the cavity (21) is filled with filling gas.

2. The hollow structure commercial vehicle exterior decoration part according to claim 1, characterized in that: The panel (1) and the reinforcement part (2) are an integrated structure and are both made of PDCPD material.

3. The hollow structure commercial vehicle exterior decoration part according to claim 1, characterized in that: The filling gas is nitrogen.

4. The hollow structure commercial vehicle exterior decoration part according to claim 1, characterized in that: The reinforcement portion (2) is provided with a plurality of holes (23).

5. The hollow structure commercial vehicle exterior decoration part according to claim 1, characterized in that: The reinforcement part (2) is provided with a plurality of fixing structures (22).

6. The hollow structure commercial vehicle exterior decoration part according to claim 5, characterized in that: The fixing structure (22) is a pre-embedded nut.

7. The hollow structure commercial vehicle exterior decoration part according to claim 1, characterized in that: The upper edge of the panel (1) is bent backwards to form a first flange (11), and the lower edge of the panel (1) is bent backwards to form a second flange (12).

8. A mold for manufacturing a hollow structure commercial vehicle exterior decoration part according to any one of claims 1 to 7, comprising a front half mold (3) and a rear half mold (4), wherein the front half mold (3) and the rear half mold (4) are combined to form a sealed cavity (5), characterized in that: The outer side surface of the front half mold (3) is provided with a first connecting seat (31), and the first connecting seat (31) is provided with a feed port (32), and the feed port (32) is connected with the mold cavity (5) through a feed channel; The mold cavity (5) is provided with an air inlet (45); The outer side surface of the rear half mold (4) is provided with a second connecting seat (41), and the second connecting seat (41) is provided with an air valve (42). The air inlet end of the air valve (42) is connected to the high-pressure air source, and the air outlet end of the air valve (42) is connected to the air inlet (45) through the air guide pipe (43).

9. The mold according to claim 8, characterized in that: The mold cavity (5) is provided with an exhaust groove (44).

10. The mold according to claim 8, characterized in that: The first connecting seat (31) and the second connecting seat (41) are arranged opposite to each other.

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