Method of manufacturing vehicle lamp assembly, vehicle lamp assembly and manufacturing device

Abstract

The manufacturing method of the vehicle lamp assembly disclosed in the application comprises the following steps: manufacturing a lamp shell, using a micro-foaming injection molding process to form the PC / ABS material into the lamp shell, wherein the lamp shell has a closed-cell micro-porous structure; welding the lamp shell and the lamp cover, using a vibration welding process to vibrationally weld the prepared PC / ABS lamp shell and the PMMA lamp cover, thereby forming a vehicle lamp assembly with a closed vehicle lamp cavity; and performance detection, performing air tightness performance detection and structural strength detection on the prepared vehicle lamp assembly. The manufacturing method of the vehicle lamp assembly disclosed in the application can reduce the weight of the lamp shell, meet the use requirement of vehicle lightening, and improve the production efficiency by using the micro-foaming injection molding process to form the PC / ABS material into the tail lamp shell; and the air tightness and structural strength of the vehicle lamp assembly are guaranteed by using specific vibration welding parameters suitable for the PC / ABS foaming lamp shell and the PMMA material.

Description

Technical Field

[0001] This application relates to the field of automotive lighting technology, and more specifically, to a method for manufacturing an automotive lighting assembly, an automotive lighting assembly, and a manufacturing apparatus. Background Technology

[0002] As the automotive industry continues to move towards lightweighting, integration, cost reduction, and efficiency improvement, both complete vehicles and components need to be iterated, optimized, and upgraded in tandem. As a key functional component and exterior part of the vehicle, the level of lightweighting and manufacturing efficiency of headlights has a significant impact on the overall performance of the vehicle.

[0003] Currently, the mainstream mass production process for taillight housings generally uses solid PC / ABS injection molding. However, this technology has the following drawbacks: the components are heavy, resulting in insufficient weight reduction. The dense solid PC / ABS injection-molded housing material offers no room for weight reduction, making it difficult to meet the overall vehicle weight reduction requirements. Furthermore, solid injection molding has a long cycle time, limiting production efficiency. Due to the dense material and slow heat dissipation, the cooling time in solid injection molding is long, making it difficult to further shorten the overall molding cycle and hindering improvements in production efficiency.

[0004] In summary, the existing manufacturing technology for automotive lighting assemblies is insufficient in terms of lightweighting and production efficiency, and further improvements are needed. Summary of the Invention

[0005] In view of this, the purpose of this application is to provide a method for manufacturing a vehicle lighting assembly, so as to achieve lightweighting of the vehicle lighting assembly and improve production efficiency.

[0006] Another objective of this application is to disclose a vehicle lamp assembly manufactured using the aforementioned method for manufacturing vehicle lamp assemblies.

[0007] Another objective of this application is to disclose a manufacturing apparatus for the aforementioned vehicle lighting assembly.

[0008] To achieve the above objectives, this application provides the following technical solution:

[0009] A method for manufacturing a vehicle headlight assembly, comprising the steps of:

[0010] The lamp housing is manufactured by molding PC / ABS material into a lamp housing using a micro-foaming injection molding process. The lamp housing has a closed-cell microporous structure.

[0011] The lamp housing and lamp cover are welded together using a vibration welding process to vibrately weld the PC / ABS lamp housing and PMMA lamp cover to form a lamp assembly with a sealed lamp cavity.

[0012] Performance testing involves conducting airtightness and structural strength tests on the manufactured vehicle lighting assembly.

[0013] Optionally, in the above-described method for manufacturing the vehicle lamp assembly, in the step of welding the lamp housing and lamp cover, the welding pressure of the vibration welding process is 2940N to 6860N.

[0014] Optionally, in the above-mentioned method for manufacturing the vehicle lamp assembly, in the step of welding the lamp housing and lamp cover, the welding depth of the vibration welding process is 0.6mm-1.0mm; and the welding amplitude of the vibration welding process is 0.9mm-1.3mm.

[0015] Optionally, in the above-mentioned method for manufacturing the vehicle lamp assembly, in the step of welding the lamp housing and lamp cover, the heating time of the vibration welding process is 8s-12s; and the holding time of the vibration welding process is 2.5s-3.5s.

[0016] Optionally, in the above-mentioned method for manufacturing the vehicle lamp assembly, in the step of welding the lamp housing and the lamp cover, the heating power of the vibration welding process is controlled by partitioning, dividing the welding area of ​​the lamp housing and the lamp cover into a middle area and side areas located on both sides of the middle area; the lamp housing and the lamp cover use the same heating power in the middle area, and in the side areas, the heating power of the lamp cover is higher than that of the lamp housing.

[0017] Optionally, in the above-mentioned method for manufacturing the vehicle lamp assembly, the vibration welding process further includes a pre-compression step in the step of welding the lamp housing and lamp cover, wherein the duration of the pre-compression step is 1s-3s.

[0018] Optionally, in the above-mentioned method for manufacturing the vehicle lamp assembly, in the step of manufacturing the lamp housing, the micro-foaming injection molding process uses supercritical nitrogen or supercritical carbon dioxide as a foaming agent.

[0019] Optionally, in the above-mentioned method for manufacturing the vehicle lamp assembly, in the step of making the lamp housing, the holding pressure of the micro-foaming injection molding process is 50 bar-55 bar, and the holding time is 0.2 s-0.5 s.

[0020] A vehicle lighting assembly is manufactured using the aforementioned vehicle lighting assembly manufacturing method.

[0021] An apparatus for manufacturing a vehicle lighting assembly, comprising:

[0022] Micro-foaming injection molding machine is used to micro-foam injection mold PC / ABS material into taillight housings;

[0023] Vibration welding machine is used to vibrately weld PC / ABS taillight housings and PMMA lamp covers to form a vehicle lamp assembly with a sealed lamp cavity.

[0024] As can be seen from the above scheme, the manufacturing method of the vehicle lamp assembly disclosed in this application, by using a micro-foaming injection molding process to mold PC / ABS material into a taillight housing, can reduce the weight of a single housing and meet the requirements for lightweighting of the entire vehicle; by using a micro-foaming injection molding process, the injection molding cycle is shortened, which can improve production efficiency; by using specific vibration welding parameters adapted to PC / ABS foam housing and PMMA material, the airtightness and structural strength of the vehicle lamp assembly are guaranteed, enabling the micro-foaming injection molding process to be applied to airtight taillight products that require a sealed cavity structure; the heating power of the vibration welding process is controlled by zones, which can match the heat input during the welding process with the stress requirements of each area, reduce the risk of welding deformation caused by stress differences, and improve the uniformity and reliability of welding quality; through whole-lamp PV test and violent destruction test verification, the vehicle lamp assembly manufactured by the method of this application meets the mass production standards in terms of airtightness and structural strength.

[0025] The vehicle lighting assembly disclosed in this application has the same technical effect as the manufacturing method of the vehicle lighting assembly, and will not be described in detail here.

[0026] The manufacturing apparatus for the vehicle lighting assembly disclosed in this application, through the configuration of its micro-foaming injection molding machine and vibration welding machine, can realize the above-mentioned manufacturing method and also has the beneficial effects of the above-mentioned manufacturing method, such as lightweighting, improved production efficiency, and ensuring airtightness and structural strength. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 This is a flowchart illustrating the manufacturing method of the vehicle lighting assembly disclosed in an embodiment of this application;

[0029] Figure 2 A comparison chart of the cycle times for conventional injection molding and micro-foaming injection molding disclosed in the embodiments of this application;

[0030] Figure 3 This is a schematic diagram showing the partitioning of the welding area between the lamp housing and the lamp shade as disclosed in the embodiments of this application.

[0031] The annotations in the attached figures are explained as follows:

[0032] 100 lamp housing, 200 lamp shade, 300 middle area, 400 side area. Detailed Implementation

[0033] The core of this application is to disclose a method for manufacturing a vehicle lighting assembly, so as to achieve lightweighting of the vehicle lighting assembly and improve production efficiency.

[0034] Another objective of this application is to disclose a vehicle lamp assembly manufactured using the aforementioned method for manufacturing vehicle lamp assemblies.

[0035] Another objective of this application is to disclose a manufacturing apparatus for the aforementioned vehicle lighting assembly.

[0036] As used in this application, the term PC / ABS refers to polycarbonate / acrylonitrile-butadiene-styrene copolymer alloy, a thermoplastic polymer alloy material made by blending polycarbonate (PC) and acrylonitrile-butadiene-styrene copolymer (ABS). PC / ABS alloys combine the excellent mechanical properties, heat resistance, and dimensional stability of polycarbonate with the good processing flow and moldability of ABS resin, making them suitable for injection molding of complex automotive parts with high dimensional accuracy requirements, such as headlight housings.

[0037] PMMA stands for polymethyl methacrylate, commonly known as acrylic or plexiglass. PMMA is a commonly used material for automotive taillight covers.

[0038] The mainstream mass production process for automotive taillight housings generally uses solid PC / ABS material injection molding. Solid PC / ABS injection-molded housings are dense and offer no space for weight reduction, making it difficult to meet the lightweight requirements of the entire vehicle. Furthermore, due to the density of the material, solid injection molding results in slow heat dissipation and a long cooling time, making it difficult to further shorten the overall molding cycle and hindering production efficiency. While micro-foam injection molding technology has been applied to non-airtight interior and exterior parts such as automotive door panels and dashboard frames, its sealing reliability is limited. The industry generally believes that micro-foam injection-molded PC / ABS housings cannot guarantee sealing performance when vibratedly welded to PMMA lamp covers. Therefore, this process has not been applied to airtight taillight housings requiring a sealed cavity structure. Based on this, this application provides a method for manufacturing an automotive lamp assembly, an automotive lamp assembly, and a manufacturing apparatus.

[0039] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0040] like Figure 1 As shown in the figure, this application discloses a method for manufacturing a vehicle lighting assembly, including the following steps:

[0041] Step S1: Make lamp housing 100;

[0042] The taillight housing 100 is formed from PC / ABS material using a micro-foaming injection molding process. This creates a closed-cell microporous structure inside the housing 100, thereby reducing its weight and shortening the injection molding cycle. Specifically, dried PC / ABS polymer alloy raw materials are fed into the barrel of an injection molding machine, heated and melted, and then formed into the taillight housing 100 using a micro-foaming injection molding process.

[0043] The microfoaming injection molding process uses supercritical fluid as a foaming agent, which can be supercritical nitrogen or supercritical carbon dioxide. In the embodiments of this application, supercritical nitrogen is injected into the molten PC / ABS polymer alloy in the barrel. With the shearing and mixing action of the screw, the supercritical nitrogen is uniformly dissolved inside the PC / ABS polymer alloy melt to form a single-phase homogeneous system. Subsequently, the homogeneous melt is injected into the mold cavity and cooled and solidified to obtain a lamp housing 100 with a closed-cell microporous structure.

[0044] In some specific embodiments of this application, the gas filling ratio can be from 0.4 wt% to 0.48 wt%, where the gas filling ratio refers to the percentage of supercritical nitrogen injected relative to the total mass of the PC / ABS material. If the gas filling ratio is too low, foaming will be insufficient, and the weight reduction effect will be insignificant; if the gas filling ratio is too high, the cell density will be too large, potentially leading to cell merging and a decrease in product surface quality or even material performance degradation. For example, the gas filling ratio can be any value or a value between 0.4 wt%, 0.45 wt%, or 0.48 wt%. A gas filling ratio of 0.4 wt% is preferred, as it balances product foaming effect, performance, surface finish, and process stability.

[0045] In some specific embodiments of this application, the holding pressure transition position in microfoamed injection molding can be 26mm to 27mm, the holding pressure can be 50bar to 55bar, the holding time can be 0.2s to 0.5s, and the injection time can be 1.45s to 1.59s. Compared to solid injection molding (the original process without foaming), which requires a longer holding time to compensate for melt cooling and shrinkage, in this solution, the internal pressure generated by the growth of bubbles after the melt enters the cavity can achieve shrinkage compensation. This effectively suppresses product shrinkage and yields dimensionally stable products without the need for prolonged holding pressure. If the holding time is too long, it not only prolongs the molding cycle but may also compress the already formed microporous structure; if the holding time is too short, the gate will not be completely closed before the pressure is released, which may lead to material backflow or uneven shrinkage. For example, the holding pressure can be 50bar or 55bar, and the holding time can be 0.2s or 0.5s.

[0046] Injection time refers to the time it takes for the melt to fill the mold cavity. Because supercritical nitrogen dissolves in the PC / ABS polymer alloy melt, it reduces the melt viscosity and improves fluidity, thus increasing the filling speed. The injection time for solid injection molding is typically around 3.5 seconds. This application demonstrates a shorter injection time compared to solid injection molding, which is beneficial for improving production efficiency. If the injection time is too long, the molding cycle will be prolonged; if the injection time is too short, defects such as unstable filling or jetting may occur.

[0047] In some specific embodiments of this application, the cooling time for microfoam injection molding can be 35 seconds. In microfoam injection molding, the presence of micropores within the foam core layer shortens the heat conduction path along the wall thickness, thereby increasing the cooling rate. The cooling time for solid injection molding is typically around 40 seconds. Compared to solid injection molding, the cooling time of this application is shortened, thus further improving production efficiency.

[0048] In some specific embodiments of this application, the typical parameters and molding effects of microfoaming injection molding process and solid injection molding process are compared as shown in Table 1.

[0049] Table 1 Verification Record of Foaming Molding Process for Rear Door Lamp Housing

[0050]

[0051] The original process (no foaming) was used as the baseline group for injection molding. The three groups of foaming processes A, B and C all used micro-foaming injection molding. The only difference between the three groups was the nitrogen filling ratio (0.4wt%, 0.45wt% and 0.48wt% respectively). All other injection molding process parameters were kept the same.

[0052] From Table 1 and Figure 2It can be seen that the holding time of the original process is 6s, while the holding time of foaming processes A, B, and C is shortened to 0.2s-0.5s, a reduction of more than 90%. This indicates that the internal pressure generated by bubble growth during microfoaming injection molding plays a compensating role, allowing for the acquisition of dimensionally stable products without the need for prolonged holding time. The injection time of the original process is 3.5s, while the injection time of foaming processes A, B, and C is shortened to 1.45s-1.59s, a reduction of approximately 55%. This indicates that the dissolution of supercritical nitrogen in the PC / ABS polymer alloy melt reduces the melt viscosity and improves the filling fluidity. The cooling time of the original process is 40s, while the cooling time of foaming processes A, B, and C is 35s, a reduction of 12.5%. This indicates that the presence of micropores in the foamed core layer shortens the heat conduction path along the wall thickness, accelerating cooling and solidification. The original process produces a product with a gram weight of 530g. The gram weights of products produced by foaming processes A, B, and C are 508g, 497g, and 490g, respectively, representing a weight reduction of approximately 4% to 7.5%. The weight reduction effect increases with the increase of nitrogen filling ratio. While foaming processes B and C show more significant weight reduction effects, they are at their limits and in a material shortage NG state, respectively, making mass production infeasible. The original process has a molding cycle time (CT) of 77s, while the molding cycle time (CT) of foaming processes A, B, and C is 65s, a reduction of approximately 15.6%. The holding time, injection time, and cooling time are all shortened, thereby reducing the molding cycle and improving production efficiency.

[0053] In the three foaming processes, foaming process A, with a nitrogen filling ratio of 0.4 wt%, produced a qualified product with good appearance, performance meeting standards, and stable process. Foaming process B, with a nitrogen filling ratio of 0.45 wt%, further reduced the basis weight to 497 g, but the product reached its limit, and the process window narrowed. Foaming process C, with a nitrogen filling ratio of 0.48 wt%, achieved a minimum basis weight of 490 g, but was in a "material shortage NG" state, indicating that an excessively high gas filling ratio resulted in excessively low melt viscosity and insufficient filling, making the product unsuitable for mass production. Considering the foaming effect, product performance, surface quality, and process stability, foaming process A with a nitrogen filling ratio of 0.4 wt% is the optimal process condition, achieving good weight reduction while ensuring product qualification and process stability.

[0054] Taking the foaming process A, which is feasible for mass production, as an example, the weight of the lamp assembly is reduced from 530g in solid injection molding to 508g, a reduction of about 4.2%, and the molding cycle is shortened from 77s in solid injection molding to 65s, a reduction of about 15.6%.

[0055] Step S2: Weld the lamp housing 100 and the lamp shade 200;

[0056] The lamp housing 100 obtained in step S1 is vibratedly welded to the PMMA lamp cover 200 using a vibration welding process to form a vehicle lamp assembly with a sealed lamp cavity. The PMMA lamp cover 200 can be pre-prepared using an injection molding process; the specific preparation method can employ techniques known in the art, which will not be elaborated here. Vibration welding is a joining technique that utilizes the heat generated by the friction between two thermoplastic workpieces under pressure, causing the contact surface material to melt and then solidify upon cooling. Vibration welding is suitable for thermoplastic materials, such as PC / ABS polymer alloys and amorphous resins like PMMA.

[0057] Specifically, the lamp housing 100 and the PMMA lamp shade 200 are respectively fixed in the upper and lower clamps of the vibration welding equipment, aligning their welding interfaces. The vibration welding machine includes a pressure control module, an amplitude adjustment module, a depth control module, and a heating power control module, which are used to control welding parameters such as welding pressure, welding amplitude, welding depth, and heating power, respectively. The vibration welding equipment is started, causing the lamp housing 100 and lamp shade 200 to vibrate relative to each other along the welding interface direction under the set welding pressure. Frictional heat generation gradually softens and melts the material at the welding interface. Once the material at the welding interface reaches a fully molten state, vibration is stopped, and pressure is maintained to allow the molten material to cool and solidify under pressure, forming a strong welded joint.

[0058] For the specific material combination of PC / ABS bulb housing 100 and PMMA lampshade 200, this embodiment employs specific vibration welding parameters. Because the PC / ABS bulb housing 100 has a closed-cell microporous structure, if the welding pressure is too high or the welding parameters are inappropriate, the micropores at the welding interface may undergo plastic deformation or even interconnect under the combined action of pressure and vibration, forming leakage channels that penetrate the welding interface, thus leading to airtightness failure. In some specific embodiments of this application, the mechanical properties of the PC / ABS bulb housing 100 differ from those of solid materials, requiring precise control of welding parameters during the welding process to suppress damage to the microporous structure. This application experimentally verifies and determines the above parameter range, ensuring that the energy input at the welding interface matches the material melting requirements. This prevents both excessive energy leading to micropore collapse and insufficient energy leading to incomplete welding.

[0059] In some specific embodiments of this application, the welding pressure for vibration welding can be 2940N-6860N (i.e., 300kgf-700kgf). Exemplarily, the welding pressure can be any value or a value between any two of 300kgf, 400kgf, 400kgf, 600kgf, and 700kgf. Welding pressure is a key parameter in the vibration welding process. When the welding pressure is too low, the material at the welding interface cannot fully melt, resulting in insufficient welding strength. When the welding pressure is too high, the stress on the micropore walls at the welding interface of the lamp housing 100 may exceed the yield strength of the material, causing the micropores to plastically collapse or even interconnect, thus compromising the sealing performance. Controlling the welding pressure within the range of 2940N-6860N allows for sufficient melting of the welding interface material to achieve a firm connection, while also preventing the micropores from being pressure-induced to interconnect during the welding process, thereby ensuring both welding strength and airtightness.

[0060] In some specific embodiments of this application, the welding depth of the vibration welding process can be from 0.6 mm to 1.0 mm. Exemplarily, the welding depth can be any value among 0.6 mm, 0.8 mm, and 1.0 mm, or a value between any two of these. Welding depth refers to the relative displacement of the lamp housing 100 and the lamp shade 200 in the direction perpendicular to the welding interface during the welding process, reflecting the degree of melting and compression of the welding interface material. Controlling the welding depth within the range of 0.6 mm to 1.0 mm ensures sufficient material melting at the welding interface to form a reliable weld joint, while reducing the risk of deformation of the lamp housing 100 or lamp shade 200 or excessive compression of the microporous structure due to excessively deep welding.

[0061] In some specific embodiments of this application, the welding amplitude of the vibration welding process can be from 0.9 mm to 1.3 mm. Exemplarily, the welding amplitude can be any value or a value between any two of 0.9 mm, 1.0 mm, 1.1 mm, 1.2 mm, and 1.3 mm. The welding amplitude refers to the relative vibration amplitude of the lamp housing 100 and the lamp shade 200 along the welding interface direction during the welding process, directly affecting the rate of frictional heat generation and welding efficiency. Too small an amplitude will result in insufficient frictional heat generation, and the welding interface will not be able to fully melt; too large an amplitude will lead to instability in the welding process, potentially causing excessive deformation of the microporous structure. Controlling the welding amplitude within the range of 0.9 mm to 1.3 mm can ensure stable frictional heat generation while reducing adverse effects on the microporous structure.

[0062] In some specific embodiments of this application, the heating time for vibration welding can be 8s-12s, and the holding time can be 2.5s-3.5s. Exemplarily, the heating time can be any value or a value between any two of 8s, 9s, 10s, 11s, and 12s, and the holding time can be any value or a value between any two of 2.5s, 3s, and 3.5s. The heating time refers to the time during which vibration is applied during vibration welding, i.e., the time period during which frictional heat causes the welding interface material to melt. The holding time refers to the time period during which welding pressure is maintained after vibration stops, allowing the molten material to cool and solidify. Reasonable heating and holding times ensure that the welding interface fully melts and solidifies, resulting in reliable welding quality.

[0063] In some specific embodiments of this application, the heating power of vibration welding is controlled by zones, such as... Figure 3 As shown, the welding area between the lamp housing 100 and the lamp shade 200 is divided into a middle region 300 and side regions 400 located on both sides of the middle region 300. The lamp housing 100 and the lamp shade 200 use the same heating power in the middle region 300, while in the side region 400, the heating power of the lamp shade 200 is higher than that of the lamp housing 100.

[0064] Specifically, the lamp housing 100 and lamp shade 200 have essentially the same shape and fit together perfectly in the welding mating area. The welding mating area extends along the contours of the lamp housing 100 and lamp shade 200, including a central area 300 and side areas 400 located on either side of the central area 300; the mating area of ​​the central area 300 is larger, while the mating areas of the side areas are smaller. The heating power of the vibration welding is controlled by zones. Specifically, the welding mating area of ​​the lamp housing 100 and lamp shade 200 is divided into a central area 300 and side areas 400 located on either side of the central area 300. The lamp housing 100 and lamp shade 200 in the central area 300 use the same heating power to ensure consistent welding quality. For example, the heating power of the lamp housing 100 in the central area 300 can be 50% to 70% of the rated power, and the heating power of the lamp shade 200 can be 50% to 70% of the rated power. In the side areas 400, the heating power of the lamp shade 200 is higher than that of the lamp housing 100. For example, in the side region 400, the heating power of the lamp housing 100 can be 5% to 25% of the rated power, and the heating power of the lamp shade 200 can be 70% to 90% of the rated power. Since the mating area of ​​the middle region 300 is larger and the force distribution is more uniform, while the mating area of ​​the side region 400 is smaller and the force is more concentrated, the heating power of the lamp shade 200 in the side region 400 is set to be higher than that of the lamp housing 100 to compensate for the force difference in this region and reduce the risk of welding deformation caused by force concentration.

[0065] In some specific embodiments of this application, the vibration welding process may further include a pre-compression step. The pre-compression step refers to pressing the lamp housing 100 and the lamp shade 200 together with a predetermined pre-compression force before formally applying vibration, ensuring close contact between their welding interfaces and preparing for subsequent vibration welding. The duration of the pre-compression step can be 1-3 seconds. Exemplarily, the pre-compression time can be any value from 1 second, 2 seconds, and 3 seconds, or any value between two of these. If the pre-compression time is too short, the welding interfaces of the lamp housing and the lamp shade cannot be fully fitted, and relative displacement may occur during vibration, affecting welding accuracy and sealing reliability. If the pre-compression time is too long, it will prolong the production cycle of a single product, reducing overall production efficiency. Therefore, this application preferably controls the pre-compression time to between 1 and 3 seconds, ensuring both sufficient fit of the welding interfaces and maintaining production efficiency.

[0066] In some specific embodiments of this application, the vibration welding mode can be a depth mode. Depth mode refers to using welding depth as the primary control target of the welding process; when the welding depth reaches a preset value, the welding process automatically stops. Depth mode can more precisely control the amount of melt at the welding interface, ensuring the consistency and reliability of the weld joint.

[0067] After vibration welding in step S2, the PC / ABS bulb housing 100 and the PMMA lamp cover 200 form a strong sealed connection at the welding interface, together forming a sealed vehicle lamp cavity.

[0068] Step S3: Performance testing;

[0069] Step S31: Welding strength test;

[0070] The weld strength of the completed headlight assembly is verified, including the following items:

[0071] (1) Violent Destruction Test: Four headlight assembly samples were taken, and the headlight cover was damaged by force (200mm). The fracture condition of the welded area was observed, and the weld strength level was determined according to the enterprise standard. After testing, the weld strength level reached level 4, which was deemed qualified.

[0072] (2) Alcohol test: The welded headlight assembly is installed on the inspection fixture, and the welded area is sprayed with 99.7% alcohol. Then, a watertightness test is performed. The test showed no leakage in the welded area, and the assembly was deemed qualified.

[0073] (3) Explosion test: Take two qualified airtight vehicle lamp assembly samples, continuously inflate and pressurize the sealed cavity, and test the maximum pressure that the lamp can withstand. The test showed that the lamp did not explode when the inflation pressure reached 76.4 kPa, which meets the standard requirement (≥75 kPa) and is judged to be qualified.

[0074] (4) Comparison test of air tightness before and after annealing: The air tightness of the welded headlight assembly was tested before annealing, and then tested again after annealing and verified by lighting. The test results showed that the air tightness was qualified before and after annealing, and the headlights lit up normally, so it was judged to be qualified.

[0075] Step S32: Whole lamp PV test. The welded automotive lamp assembly is subjected to a whole lamp PV (Product Validation) test. The specific test items and results are shown in Table 2.

[0076] Table 2. PV Test Items and Results for the Whole Lamp

[0077]

[0078] All the above performance tests were conducted in accordance with GWTA D21-03:2024-09 "Technical Conditions for Automobile Combination Rear Lights". The tests showed that all items were qualified, indicating that the vehicle lighting assembly manufactured using the method described in this application meets the standards for mass production use.

[0079] The manufacturing method of the vehicle lamp assembly disclosed in this application employs a micro-foaming injection molding process to mold PC / ABS material into a taillight housing 100, creating a closed-cell microporous structure within the housing 100. This reduces the weight of the vehicle lamp assembly from 530g (solid injection molding) to 508g, a reduction of approximately 4.2%, thus lowering the unit weight of the housing 100 and meeting the lightweight requirements of the entire vehicle. The micro-foaming injection molding process also shortens the injection molding cycle from 77s to 65s (solid injection molding), a reduction of approximately 15.6%. Simultaneously, the holding pressure time is reduced from 6s to 0.5s, and the injection time from 3.5s to 1.59s, improving production efficiency. Furthermore, by employing specific vibration welding parameters adapted to the PC / ABS foamed housing 100 and PMMA material, with a welding pressure of 2940N-6860N, the risk of micropore perforation during welding is reduced, ensuring the airtightness of the vehicle lamp assembly. The structural strength allows the micro-foaming injection molding process to be applied to airtight taillights requiring a sealed cavity structure. The explosion test verified that the taillight assembly did not explode when the inflation pressure reached 76.4 kPa, meeting the standard requirement (≥75 kPa) and demonstrating good airtight reliability. The heating power of the vibration welding process is controlled by zones, ensuring that the heat input during welding matches the stress requirements of each area, reducing the risk of welding deformation due to stress differences and improving the uniformity and reliability of the welding quality. The whole-lamp PV test verified that the taillight assembly manufactured using this method passed all eight tests: high-temperature alcohol test, random vibration test, high-temperature operation test, high-temperature storage test, low-temperature storage test, temperature shock test, mechanical shock test, and mechanical durability test. This indicates that the taillight assembly has good environmental adaptability and mechanical reliability, meeting mass production standards. The violent destruction test verified that the welding strength level reaches level 4, indicating reliable welding quality.

[0080] Furthermore, this application also discloses a vehicle lamp assembly manufactured using any of the aforementioned manufacturing methods. Specifically, the vehicle lamp assembly includes a PC / ABS foamed lamp housing 100 and a PMMA lamp cover 200. The lamp housing 100 has a closed-cell microporous structure, and the lamp housing 100 and the lamp cover 200 are formed into a sealed cavity through vibration welding. Due to the aforementioned manufacturing methods, this vehicle lamp assembly achieves lightweight design while possessing excellent airtightness and structural strength.

[0081] Furthermore, this application also provides a manufacturing apparatus for a vehicle lamp assembly, comprising a micro-foaming injection molding machine and a vibration welding machine. The micro-foaming injection molding machine is used to micro-foam and injection mold PC / ABS material into a taillight housing 100. The micro-foaming injection molding machine may include a supercritical fluid injection device for injecting supercritical nitrogen or supercritical carbon dioxide into the PC / ABS polymer alloy melt at a predetermined gas filling ratio. The vibration welding machine is used to vibrately weld the PC / ABS foamed housing 100 to a PMMA lamp cover 200 to form a vehicle lamp assembly with a sealed lamp cavity. The vibration welding machine may include a pressure control module, an amplitude adjustment module, a depth control module, and a heating power control module, respectively used to control welding parameters such as welding pressure, welding amplitude, welding depth, and heating power. The vehicle lamp assembly manufacturing apparatus disclosed in this application, through its configuration of a micro-foaming injection molding machine and a vibration welding machine, can realize the above-mentioned manufacturing method and also possesses the beneficial effects of the above-mentioned manufacturing method, such as lightweighting, improved production efficiency, and ensuring airtightness and structural strength.

[0082] The terminology used in the above embodiments is for the purpose of describing specific embodiments only and is not intended to be limiting of this application. As used in the specification and appended claims of this application, the singular expressions "a," "an," "the," "the," "the," and "this" are intended to also include expressions such as "one or more," unless the context clearly indicates otherwise. It should also be understood that in the embodiments of this application, "one or more" refers to one, two, or more; "and / or" describes the relationship between related objects, indicating that three relationships may exist; for example, A and / or B can represent: A alone, A and B simultaneously, or B alone, where A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship.

[0083] References to "one embodiment" or "some embodiments" as described in this specification mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0084] It should be noted that in the description of the embodiments of this application, the terms "first" and "second" are used only for the purpose of distinguishing descriptions and should not be construed as indicating or implying relative importance, nor should they be construed as indicating or implying order.

[0085] In the description of this application, it should be noted that, unless otherwise explicitly specified and limited, the technical terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to fixed connections or detachable connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; or internal connections between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0086] The above description of the disclosed embodiments enables those skilled in the art to make or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method of manufacturing a vehicle lamp assembly, characterized by, Including the following steps: The lamp housing (100) is manufactured by molding PC / ABS material into a lamp housing (100) using a micro-foaming injection molding process. The lamp housing (100) has a closed-cell microporous structure. The lamp housing (100) and lamp cover (200) are welded together. The PC / ABS lamp housing (100) and PMMA lamp cover (200) are vibratedly welded together using a vibration welding process to form a lamp assembly with a sealed lamp cavity. Performance testing involves conducting airtightness and structural strength tests on the manufactured vehicle lighting assembly.

2. The method of manufacturing a vehicle lamp assembly of claim 1, wherein, In the steps of welding the lamp housing (100) and the lamp shade (200), the welding pressure of the vibration welding process is 2940N-6860N.

3. The manufacturing method of the vehicle lamp assembly as described in claim 1, characterized in that, In the steps of welding the lamp housing (100) and the lamp shade (200), the welding depth of the vibration welding process is 0.6mm-1.0mm; the welding amplitude of the vibration welding process is 0.9mm-1.3mm.

4. The manufacturing method of the vehicle lamp assembly as described in claim 1, characterized in that, In the steps of welding the lamp housing (100) and the lamp shade (200), the heating time of the vibration welding process is 8s-12s; the holding time of the vibration welding process is 2.5s-3.5s.

5. The method for manufacturing the vehicle lamp assembly as described in claim 1, characterized in that, In the step of welding the lamp housing (100) and the lamp shade (200), the heating power of the vibration welding process is controlled by partitioning, dividing the welding area of ​​the lamp housing (100) and the lamp shade (200) into a middle region (300) and side regions (400) located on both sides of the middle region (300); the lamp housing (100) and the lamp shade (200) use the same heating power in the middle region (300), and in the side region (400), the heating power of the lamp shade (200) is higher than that of the lamp housing (100).

6. The method for manufacturing the vehicle lamp assembly as described in claim 1, characterized in that, In the steps of welding the lamp housing (100) and the lamp shade (200), the vibration welding process further includes a pre-compression step, the duration of which is 1s-3s.

7. The method for manufacturing the vehicle lamp assembly as described in claim 1, characterized in that, In the step of manufacturing the lamp housing (100), the micro-foaming injection molding process uses supercritical nitrogen or supercritical carbon dioxide as a foaming agent.

8. The method for manufacturing the vehicle lamp assembly as described in claim 1, characterized in that, In the step of manufacturing the lamp housing (100), the holding pressure of the micro-foaming injection molding process is 50 bar-55 bar, and the holding time is 0.2 s-0.5 s.

9. A vehicle lighting assembly, characterized in that, It is manufactured using the manufacturing method of the vehicle lamp assembly as described in any one of claims 1-8.

10. A manufacturing apparatus for a vehicle lighting assembly, characterized in that, include: Micro-foaming injection molding machine, used to micro-foam injection mold PC / ABS material into taillight housing (100). A vibration welding machine is used to vibrately weld PC / ABS taillight housing (100) and PMMA lamp cover (200) to form a vehicle lamp assembly with a sealed lamp cavity.

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