Automobile instrument board forming system and method based on multi-material co-injection molding

Abstract

The invention discloses an automobile dashboard forming system and method based on multi-material co-injection molding, and relates to the field of multi-material co-injection molding, and the automobile dashboard forming system comprises a multi-station rotary mold platform, a multi-material injection molding unit and an intelligent temperature control module. According to the invention, collaborative operation of the multi-station rotary mold platform, the multi-material injection molding unit and the intelligent temperature control module is planned as a whole, rotary station circulation is taken as a core, material gradient molding is taken as a path, and accurate temperature control is taken as a guarantee, so that integrated molding of the automobile instrument panel from surface function decoration to a structural framework is realized; the rotary lifting driving device is a core transmission part and drives the core male die assembly to be accurately switched among the multiple injection molding stations, and closing and separating of the core male die assembly and the female die assemblies of all the stations are achieved. According to the modular design that the core male die assembly is matched with the female die assembly through a quick release structure, replacement of dashboard dies of different vehicle types can be completed in a short time, and the production requirements of various types are met.

Description

Technical Field

[0001] This invention relates to the field of multi-material co-injection molding technology, and in particular to an automotive dashboard molding system and method based on multi-material co-injection molding. Background Technology

[0002] As a core component of automotive interiors, the dashboard not only needs to fulfill basic functions such as structural support and safety protection, but also must possess decorative appeal, tactile comfort, and intelligent interactive capabilities, such as integrated touch controls and ambient lighting. As the automotive industry moves towards lightweighting, integration, and high-end features, traditional dashboard manufacturing processes have gradually revealed numerous limitations, as follows:

[0003] Traditional automotive dashboard production typically employs a step-by-step molding and post-assembly model, involving 7-8 independent processes such as skeleton injection molding, surface decoration bonding, soft touch layer foaming, and functional component assembly. This results in low production efficiency, poor quality consistency, and low material utilization.

[0004] While existing multi-material co-injection molding technology has improved in terms of integration, it still faces key technical bottlenecks: limited surface decoration processes: the mainstream technology uses IMD film pre-attachment, which has problems such as high film cost, easy wrinkling when bonding complex surfaces, and the need to change film molds when switching textures and patterns; some technologies have tried in-mold spraying, but there are defects such as poor coating uniformity and weak adhesion to the substrate;

[0005] Functional structures such as conductive layers and optical signal transmission layers need to be pasted or printed later, which not only increases the number of processes, but also makes them prone to functional failure due to poor interface bonding.

[0006] Traditional soft touch layers use single-component spraying or foaming, which makes it difficult to achieve hardness gradient adjustment in different areas, and the cell uniformity is poor, making them prone to collapse after long-term use.

[0007] In summary, there is an urgent need to develop a novel multi-material co-injection molding system and method to achieve integrated production from surface decoration and functional integration to structural molding, breaking through the bottlenecks of traditional processes. Summary of the Invention

[0008] To address the aforementioned technical problems, this invention provides an automotive dashboard molding system and method based on multi-material co-injection molding. The technical solution adopted is as follows:

[0009] The automotive dashboard molding system based on multi-material co-injection molding includes a multi-station rotary mold platform, a multi-material injection molding unit, and an intelligent temperature control module. The multi-station rotary mold platform includes an injection platform, multiple injection stations, multiple cavity mold assemblies, and a rotating core punch assembly. The multiple injection stations are respectively installed on the injection platform, and the multiple cavity mold assemblies are respectively installed on the multiple injection stations. The rotating core punch assembly includes a rotary lifting drive device and a core punch assembly. The rotary lifting drive device is located above the injection platform, and the core punch assembly is detachably installed on the rotary lifting part of the rotary lifting drive device.

[0010] The multi-material injection molding unit includes a multi-functional surface molding device and a main injection molding device. The soft-touch layer molding device is used to spray a multi-functional decorative layer on the inner wall of the cavity of the die assembly and the core punch assembly before the injection molding action. The main injection molding device is connected to the core punch assembly. The injection molding action is performed after the core punch assembly and the die assembly are docked.

[0011] The intelligent temperature control module controls the temperature of the mold cavity formed after the core punch assembly and the die assembly are connected.

[0012] Optionally, the multi-functional surface forming device includes a multimodal adaptive printing component and a soft-touch material precision coating component. The multimodal adaptive printing component includes a UV inkjet submodule and a functional material extrusion submodule. The UV inkjet submodule is used to spray decorative textures onto the inner walls of the cavities of the die component and the core punch component. The functional material extrusion submodule is used to print functional layers, including conductive layers and optical signal transmission layers. The soft-touch material precision coating component uses an ultrasonic vibration atomizing nozzle to spray TPO soft-touch base material onto the cavity surface after being sprayed by the UV inkjet submodule.

[0013] Optionally, the multifunctional surface forming device also includes a robotic arm, a vision positioning module, and a plasma surface activation component. The base of the robotic arm is mounted on one side of the multi-station rotary mold platform. The nozzles of the modal adaptive printing component and the soft-touch material precision coating component are respectively mounted on the movable end of the robotic arm. The vision positioning module is mounted on the movable end of the robotic arm and is used to visually identify and position the cavity positions of the concave mold component and the core punch component.

[0014] The multifunctional surface forming device also includes a plasma surface activation component, which is installed at the movable end of the robotic arm and performs low-temperature plasma treatment on the cavity surfaces of the concave mold component and the core convex mold component before the modal adaptive printing component and the soft-touch material precision coating component move.

[0015] Optionally, the main injection molding device includes an injection molding machine, an injection outlet rotary joint, a conveying pipe, and a punch inlet rotary joint. One end of the conveying pipe is connected to the molten material outlet of the injection molding machine through the injection outlet rotary joint, and the other end is connected to the injection port of the core punch assembly through the punch inlet rotary joint.

[0016] Optionally, the rotary lifting drive device includes an electric turntable and a lifting cylinder. The base of the electric turntable is mounted on a bracket. The cylinder body of the lifting cylinder is detachably mounted on the rotating part of the electric turntable and rotates with the rotating part. The piston rod of the lifting cylinder faces the injection molding station. The core punch assembly is detachably mounted on the end of the piston rod of the lifting cylinder. When the electric turntable and the lifting cylinder move, the core punch assembly is docked to achieve mold closing.

[0017] Optionally, the intelligent temperature control module includes multiple sets of circulating fluid temperature control devices, a temperature detection module, and a temperature controller. The multiple die assemblies and the core punch assembly are all equipped with temperature control channels. The circulating fluid inlets and outlets of the multiple sets of circulating fluid devices are respectively connected to the temperature control channels of the multiple die assemblies and the core punch assembly. The temperature detection module collects the internal temperature of the multiple die assemblies and the core punch assembly. The temperature controller is communicatively connected to the temperature detection module and controls the execution actions of the multiple sets of circulating fluid temperature control devices based on the temperature detection data and the set temperature control data.

[0018] Optionally, it also includes an industrial control computer, which controls the execution actions of each actuator in the multi-station rotary mold platform, the multi-material injection molding unit, and the intelligent temperature control module.

[0019] A method for molding automotive dashboards based on multi-material co-injection molding is described, which employs a multi-material co-injection molding system for automotive dashboard injection molding, and includes the following steps:

[0020] Step 1: Inject a mixed plasma of argon and carbon dioxide into the inner wall of the cavity;

[0021] Step 2: Inkjet printing is performed on the cavity surface of the die assembly, and hidden textures are simultaneously printed in the corresponding area of ​​the core punch assembly.

[0022] Step 3: Extruding conductive slurry into the die assembly to form a conductive layer and extruding optical conductive material to form an optical signal transmission layer;

[0023] Step 4: Spray a two-component TPO soft touch material onto the decorative texture and functional layer surfaces;

[0024] Step 5: The core punch assembly is transferred to the second injection molding station;

[0025] Step 6: The multi-material injection molding unit performs injection molding to obtain the finished automotive dashboard.

[0026] Optional, the following detailed steps are included:

[0027] Step 1: The industrial control computer controls the electric turntable to rotate, which moves the core punch assembly to the first injection station. The lifting electric cylinder drives the core punch assembly to descend, and the vision positioning module takes pictures of the inner wall of the cavity and feeds back the position deviation to the robotic arm.

[0028] Step 2: The robotic arm carries the plasma surface activation component into the cavity between the concave mold component and the core convex mold component, and sprays a mixed plasma of argon and carbon dioxide to perform a full-area scanning process on the inner wall of the cavity.

[0029] Step 3: Switch to the UV inkjet sub-module and inkjet print on the cavity surface of the concave mold component according to the preset pattern. Simultaneously, print hidden textures in the corresponding areas of the core convex mold component. After completion, the robotic arm is equipped with a UV lamp to cure the textures.

[0030] Step 4: The robotic arm switches to the functional material extrusion submodule, where it extrudes conductive slurry in the design area of ​​the die assembly to form a conductive layer; and extrudes optical conductive material in the edge area of ​​the dashboard to form an optical signal transmission layer.

[0031] Step 5: The robotic arm switches to the precision coating assembly for soft touch material, spraying a two-component TPO soft touch material onto the decorative texture and functional layer surfaces;

[0032] Step 6: The lifting electric cylinder drives the core punch assembly to rise, and the electric turntable rotates to transfer the core punch assembly to the second injection molding station.

[0033] Step 7: The lifting electric cylinder drives the core punch assembly and the die assembly to close, and the multi-material injection molding unit and the intelligent temperature control module operate to perform injection molding to obtain the finished car dashboard.

[0034] Optionally, a Z-axis micro-compensation mechanism can be added to the end of the robotic arm. Based on the depth deviation of the concave mold cavity fed back by the vision positioning module, the distance between the extrusion head and the cavity surface can be dynamically adjusted. The specific method of dynamic adjustment is as follows: based on the filtered deviation value, the distance of the extrusion head to be adjusted is calculated, and a compensation coefficient is introduced to avoid overshoot.

[0035] ;

[0036] in It is the distance between the extruder head and the cavity surface that is dynamically adjusted. It is the target distance between the extruder head and the cavity surface. It is a correction factor used to balance sensitivity and stability. It is the average value of the depth deviation of the concave model cavity reported by the visual positioning module in the last n times.

[0037] Optionally, in step 7, injection molding includes the following sub-steps:

[0038] Step 71: The injection molding machine starts plasticizing, heats the injection molding material to melt, and injects the melt into the tree-shaped distribution channel of the core punch assembly through the delivery pipe. Finally, it radiates from multiple distribution ports into the mold cavity.

[0039] Step 72: After the melt fills the cavity, the injection molding machine switches to the holding pressure mode and continues for a set time. The intelligent temperature control module keeps the core punch assembly and the die assembly at the set temperature.

[0040] Step 73: After the heat preservation and pressure holding are completed, the industrial control computer instructs the intelligent temperature control module to switch to cooling mode. After cooling, the lifting electric cylinder drives the core punch assembly to rise and separate from the die assembly, and the finished car dashboard is removed.

[0041] In summary, the present invention has at least one of the following beneficial technical effects:

[0042] This invention provides an automotive dashboard molding system and method based on multi-material co-injection molding. It coordinates the collaborative operation of a multi-station rotary mold platform, multi-material injection molding units, and an intelligent temperature control module. With rotary station flow as the core, material gradient molding as the path, and precise temperature control as the guarantee, it achieves integrated molding of the automotive dashboard, from surface functional decoration to structural framework. A rotary lifting drive device serves as the core transmission component, driving the core punch assembly to precisely switch between multiple injection molding stations, achieving the closing and separation of the core punch assembly with the die assemblies at each station. The core punch assembly, through a quick-release structure and modular design of the die assemblies, allows for the rapid replacement of dashboard molds for different vehicle models, meeting the needs of multi-variety production.

[0043] The soft-touch layer molding device in the multi-material injection molding unit is used to spray a multi-functional decorative layer onto the inner walls of the cavity of the die assembly and the core punch assembly before the injection molding action. After the multi-functional decorative layer is sprayed, the main injection molding device performs the injection molding action. Through multi-station rotary continuous operation, the production cycle of a single instrument panel is significantly shortened. It integrates 7-8 discrete processes such as pretreatment, decoration, functional layer molding, injection molding, and cooling into an integrated system, saving material transfer time and reducing the equipment footprint. The quick-release structure of the core punch assembly greatly shortens the mold change time and is compatible with the production of instrument panels for various vehicle models. It comprehensively breaks through the efficiency, quality, and flexibility bottlenecks of traditional automotive instrument panel production, providing an industrializable technical solution for the high-end and intelligent production of automotive interiors. Attached Figure Description

[0044] Figure 1 This is a schematic diagram illustrating the structural principle of the automotive dashboard molding system based on multi-material co-injection molding of the present invention;

[0045] Figure 2This is a schematic diagram of the component connection principle of the automotive dashboard molding system based on multi-material co-injection molding according to the present invention.

[0046] Figure Descriptions: 11. Injection platform; 12. Injection station; 13. Die assembly; 14. Rotating core punch assembly; 141. Core punch assembly; 142. Electric turntable; 143. Lifting cylinder; 21. Multifunctional surface forming device; 211. Multimodal adaptive printing assembly; 212. Soft-touch material precision coating assembly; 213. Robotic arm; 214. Vision positioning module; 215. Plasma surface activation assembly; 22. Main injection unit; 221. Injection machine; 222. Injection outlet rotary joint; 223. Conveying pipe; 224. Punch inlet rotary joint; 4. Industrial control computer; 100. Support frame. Detailed Implementation

[0047] The present invention will be further described in detail below with reference to the accompanying drawings.

[0048] This invention discloses an automotive dashboard molding system and method based on multi-material co-injection molding.

[0049] Reference Figure 1 and Figure 2 Example 1: A multi-material co-injection molding system for automotive dashboards includes a multi-station rotary mold platform, a multi-material injection unit, and an intelligent temperature control module. The multi-station rotary mold platform includes an injection platform 11, multiple injection stations 12, multiple cavity mold assemblies 13, and a rotating core punch assembly 14. The multiple injection stations 12 are respectively installed on the injection platform 11, and the multiple cavity mold assemblies 13 are respectively installed on the multiple injection stations 12. The rotating core punch assembly 14 includes a rotary lifting drive device and a core punch assembly 141. The rotary lifting drive device is located above the injection platform 11, and the core punch assembly 141 is detachably installed on the rotary lifting part of the rotary lifting drive device.

[0050] The multi-material injection molding unit includes a multi-functional surface molding device 21 and a main injection molding device 22. The soft-touch layer molding device 22 is used to spray a multi-functional decorative layer on the inner wall of the cavity of the cavity assembly 13 and the core punch assembly 141 before the injection molding action. The main injection molding device 22 is connected to the core punch assembly 141. The injection molding action is performed after the core punch assembly 141 is docked with the cavity assembly 13.

[0051] The intelligent temperature control module controls the temperature of the mold cavity formed after the core punch assembly 141 and the die assembly 13 are connected.

[0052] By adopting the above technical solution, and through the coordinated operation of the multi-station rotary mold platform, multi-material injection molding unit, and intelligent temperature control module by an industrial control computer, with rotary station flow as the core, material gradient molding as the path, and precise temperature control as the guarantee, the integrated molding of automotive dashboards from surface functional decoration to structural skeleton is realized. The specific operation mechanism is as follows:

[0053] The rotary lifting drive device is the core transmission component, which drives the core punch assembly 141 to achieve 360° intermittent rotation and lifting. It can precisely switch between multiple injection stations 12 to achieve the closing and separation of the die assembly 13 at each station. Typically, there are four stations: pretreatment / decoration station, functional layer molding station, main injection station, and cooling and part removal station, which achieve the closing and separation of the die assembly 13 at each station.

[0054] The core punch assembly 141 is connected to the lifting cylinder 143 through a quick-release structure, such as a positioning pin plus electromagnetic locking. Combined with the modular design of the die assembly 13, it can complete the replacement of instrument panel molds for different models in a short time, meeting the needs of multi-variety production.

[0055] The soft-touch layer forming device 22 of the multi-material injection molding unit is used to spray a multi-functional decorative layer on the inner wall of the cavity of the cavity assembly 13 and the core punch assembly 141 before the injection molding action. After the multi-functional decorative layer is sprayed, the main injection molding device 22 performs the injection molding action.

[0056] Multiple die assemblies 13 and the core punch assembly 141 have built-in independent temperature control channels, and the intelligent temperature control module enables differentiated adjustment:

[0057] Pretreatment / decoration stage: The temperature of both the concave and convex molds is controlled at 80±5℃ to ensure sufficient UV curing and stability of the soft-touch material pre-coating;

[0058] Main injection stage: The temperature of the punch is increased to 150±5℃ (to reduce melt flow resistance), and the temperature of the die is adjusted according to the area to avoid weld lines;

[0059] Cooling stage: The cavity temperature is reduced to 40±3℃ within 10 seconds by circulating 25℃ cold water to ensure the stability of the skeleton dimensions.

[0060] Through multi-station rotary continuous operation, the production cycle of a single instrument panel is shortened from the traditional 120-180 seconds to 45-60 seconds, increasing the cycle time by 67%-75%.

[0061] By integrating 7-8 discrete processes such as pretreatment, decoration, functional layer molding, injection molding, and cooling into an integrated system, material transfer time is saved and the equipment footprint is reduced.

[0062] The quick-release structure of the core punch assembly 141 reduces the mold change time from more than 30 minutes to less than 15 minutes, and is compatible with the production of dashboards for 5-8 different car models.

[0063] It comprehensively breaks through the efficiency, quality, and flexibility bottlenecks in traditional automotive dashboard production, providing an industrializable technical solution for the high-end and intelligent production of automotive interiors.

[0064] Example 2: The multi-functional surface forming device 21 includes a multi-modal adaptive printing component 211 and a soft-touch material precision coating component 212. The multi-modal adaptive printing component 211 includes a UV inkjet sub-module and a functional material extrusion sub-module. The UV inkjet sub-module is used to spray decorative textures onto the inner walls of the cavities of the die component 13 and the core punch component 141. The functional material extrusion sub-module is used to print functional layers, including conductive layers and optical signal transmission layers. The soft-touch material precision coating component 212 uses an ultrasonic vibration atomizing nozzle to spray TPO soft-touch base material onto the cavity surface after being sprayed by the UV inkjet sub-module.

[0065] In Example 3, the multifunctional surface forming device 21 also includes a robotic arm 213 and a vision positioning module 214. The base of the robotic arm 213 is installed on one side of the multi-station rotary mold platform. The nozzles of the modal adaptive printing component 211 and the soft-touch material precision coating component 212 are respectively installed on the movable end of the robotic arm 213. The vision positioning module 214 is installed on the movable end of the robotic arm 213 and is used to visually identify and position the cavity positions of the die component 13 and the core punch component 141.

[0066] Example 4: The multifunctional surface forming device 21 also includes a plasma surface activation component 215, which is installed at the movable end of the robotic arm 213. Before the modal adaptive printing component 211 and the soft touch material precision coating component 212 are activated, the cavity surfaces of the die component 13 and the core punch component 141 are subjected to low-temperature plasma treatment.

[0067] By adopting the above technical solution, the multifunctional surface forming device 21 uses a robotic arm 213 as a motion carrier and integrates a plasma surface activation component 215, a multimodal adaptive printing component 211, a UV inkjet sub-module, a functional material extrusion sub-module, and a soft-touch material precision coating component 212. It achieves precise operation on the cavity surface through a vision positioning module 214. All components work together in a preset sequence to complete the entire process from surface activation to the forming of the functional layer and soft-touch layer, ultimately providing a substrate for subsequent injection molding that combines decorative, functional, and tactile comfort.

[0068] When the core punch assembly 141 and the die assembly 13 arrive at the designated work station, the vision positioning module 214, consisting of two sets of industrial cameras and a laser contour sensor, performs a 3D scan of the inner wall of the cavity to obtain the deviation between the actual contour and the theoretical model, and transmits the data to the control system of the robotic arm 213.

[0069] The robotic arm 213 corrects its motion trajectory in real time based on the visual positioning results, ensuring that the distance and angle between each working component and the cavity surface remain consistent, thus avoiding operational deviations caused by mold installation errors or thermal deformation.

[0070] The robotic arm 213, carrying a plasma surface activation component 215, enters the mold cavity. It sprays a mixture of Ar and CO2 gases to form a low-temperature plasma. This plasma bombards the mold cavity surface with high-energy particles, removing surface oil, oxide layers, and other impurities, significantly improving cleanliness. The introduction of polar groups such as hydroxyl (-OH) and carboxyl (-COOH) groups increases the surface energy from 30 mN / m to over 70 mN / m, significantly enhancing the adhesion of subsequent coatings. The robotic arm 213 drives the plasma nozzle along an S-shaped path to scan the entire mold cavity at a scanning speed of 50-100 mm / s, ensuring that the surface treatment time for each area is greater than 1 second, achieving uniform activation.

[0071] High-precision inkjet printing and curing: The UV inkjet submodule uses a piezoelectric printhead to spray UV-curable ink onto the activated cavity surface according to a preset pattern, forming a textured layer of 0.02-0.05mm thickness; it is equipped with a UV-LED lamp to irradiate and cure immediately after inkjet printing, avoiding ink dripping.

[0072] For the inner cavity of the core punch assembly 141, the UV inkjet submodule simultaneously prints hidden textures to achieve differentiated decoration on the front and back of the dashboard.

[0073] Using a screw-type micro-extrusion head, silver nanoparticle conductive paste is extruded into a designated area according to the circuit pattern to form a 0.1mm thick conductive layer to meet the touch sensing requirements;

[0074] For the ambient light guide area, a 0.2mm thick conductive layer is formed by extruding transparent silicone. The path is precisely controlled by a robotic arm to ensure uniform light distribution.

[0075] The extrusion temperature is adjusted according to the material properties (80℃ for conductive paste, 120℃ for silicone) to avoid high temperature damage to the cured UV texture layer.

[0076] The precision coating component 212 for soft touch materials uses an ultrasonic vibration atomizing nozzle to atomize the two-component TPO soft touch base material (component A: hydroxyl-terminated TPO; component B: isocyanate curing agent, ratio 10:1) into fine droplets of 5-10μm, which are then uniformly sprayed onto the surfaces of the decorative and functional layers using compressed air.

[0077] The entire process is linked with an industrial control computer 4 and an intelligent temperature control module to ensure that the cavity temperature is stable at 80±5℃, providing the best environment for the curing and adhesion of each coating.

[0078] The multi-functional surface forming device 21 realizes the integrated forming of decoration, function and soft touch layer, laying the core foundation for the high-quality and multi-functional production of automotive dashboards.

[0079] Example 5: The main injection molding device 22 includes an injection molding machine 221, an injection outlet rotary joint 222, a conveying pipe 223, and a punch inlet rotary joint 224. One end of the conveying pipe 223 is connected to the molten material outlet of the injection molding machine 221 through the injection outlet rotary joint 222, and the other end is connected to the injection port of the core punch assembly 141 through the punch inlet rotary joint 224.

[0080] By adopting the above technical solution, the double mechanical seal structure of the injection outlet rotary joint 222 and the punch inlet rotary joint 224 can be adapted to the 360° rotation and lifting action of the core punch assembly 141, ensuring no leakage during the melt conveying process and solving the sealing failure problem of traditional fixed connection under rotating conditions.

[0081] The combination of the conveying pipe 223 and the rotary joint enables the melt conveying path to move synchronously with the core punch, ensuring injection continuity during multi-station rotation switching and meeting the needs of multi-station integrated production.

[0082] The quick-connection design of the punch inlet rotary joint 224 and the core punch assembly 141, combined with the detachable structure of the core punch, eliminates the need to disassemble the melt delivery pipeline when changing molds, reducing the mold change time to within 15 minutes and improving the flexibility of multi-variety production.

[0083] Example 6: The rotary lifting drive device includes an electric turntable 142 and a lifting cylinder 143. The base of the electric turntable 142 is mounted on the bracket 100. The cylinder body of the lifting cylinder 143 is detachably mounted on the rotating part of the electric turntable 142 and rotates with the rotating part. The piston rod of the lifting cylinder 143 faces the injection molding station 12. The core punch assembly 141 is detachably mounted on the end of the piston rod of the lifting cylinder 143. When the electric turntable 142 and the lifting cylinder 143 move, the core punch assembly 141 is connected with the die assembly 13 to achieve mold closing.

[0084] By adopting the above technical solution, the electric turntable 142 is driven by a servo motor to drive the lifting cylinder 143 and the core punch assembly 141 to achieve 360° intermittent rotation, which can be precisely switched between multiple injection molding stations 12; the lifting cylinder 143 drives the core punch assembly 141 to lift and lower, realizing the closing and separation with the die assembly 13 of each station.

[0085] Example 7: The intelligent temperature control module includes multiple sets of circulating fluid temperature control devices, a temperature detection module, and a temperature controller. Multiple die concave components 13 and core punch components 141 are provided with temperature control flow channels. The circulating fluid inlets and outlets of the multiple sets of circulating fluid devices are respectively connected to the temperature control flow channels of the multiple die concave components 13 and core punch components 141. The temperature detection module collects the internal temperature of the multiple die concave components 13 and core punch components 141. The temperature controller is communicatively connected to the temperature detection module and controls the execution actions of the multiple sets of circulating fluid temperature control devices based on the temperature detection data and the set temperature control data.

[0086] It also includes an industrial control computer 4, which controls the execution actions of each actuator in the multi-station rotary mold platform, the multi-material injection molding unit, and the intelligent temperature control module.

[0087] By adopting the above technical solution, multiple sets of circulating fluid temperature control devices correspond one-to-one with the independent temperature control channels of the die assembly 13 and the core punch assembly 141, enabling differentiated adjustment according to the temperature requirements of different workstations:

[0088] Pretreatment stage: The temperature of the concave mold and the convex mold is kept stable at 80±5℃ to ensure sufficient UV curing and uniform coating of soft-touch material, avoiding sagging caused by low temperature or premature curing caused by high temperature;

[0089] In the injection stage: the temperature of the punch is independently increased to 150±5℃ to reduce melt flow resistance, and the temperature of the die is set to 140℃ (edge) / 120℃ (center) according to the area to reduce weld lines and improve filling fullness;

[0090] Cooling stage: The cavity temperature is rapidly reduced to 40±3℃ by circulating 25℃ cold water to ensure the stability of the skeleton dimensions.

[0091] Compared to the traditional unified temperature control mode, it meets the interface bonding and molding requirements of multiple materials.

[0092] The temperature detection module can collect the cavity temperature in real time based on the detection methods of the PT100 sensor and infrared thermometer, and the temperature controller dynamically adjusts the circulating fluid flow rate through the PID algorithm.

[0093] When a local temperature deviation exceeding 3°C is detected, the circulating fluid temperature or flow rate is corrected within 3 seconds to avoid defects caused by temperature fluctuations.

[0094] For the complex surface of large instrument panels, the flow distribution of the flow channel is optimized to keep the temperature difference in each area of ​​the cavity within 5°C, thereby improving product consistency.

[0095] Example 8: A method for molding an automotive dashboard based on multi-material co-injection molding. The method employs a multi-material co-injection molding system for automotive dashboard injection molding, and includes the following steps:

[0096] Step 1: Inject a mixed plasma of argon and carbon dioxide into the inner wall of the cavity;

[0097] Step 2: Inkjet printing is performed on the cavity surface of the die assembly 13, and a hidden texture is simultaneously printed in the corresponding area of ​​the core punch assembly 141.

[0098] Step 3: Extruding conductive slurry into the die assembly 13 to form a conductive layer and extruding optical conductive material to form an optical signal transmission layer;

[0099] Step 4: Spray a two-component TPO soft touch material onto the decorative texture and functional layer surfaces;

[0100] Step 5: The core punch assembly 141 is transferred to the second injection molding station;

[0101] Step 6: The multi-material injection molding unit performs injection molding to obtain the finished automotive dashboard.

[0102] The specific steps to implement the above method are as follows:

[0103] The core punch assembly 141 descends, and the vision positioning module 214 feeds back the position deviation to the robotic arm 213.

[0104] The plasma surface activation component 215 sprays a mixture of argon and carbon dioxide plasma onto the inner wall of the cavity.

[0105] The UV inkjet submodule performs inkjet printing on the cavity surface of the concave mold assembly 13 according to a preset pattern, and simultaneously prints hidden textures in the corresponding area of ​​the core convex mold assembly 141.

[0106] The functional material extrusion submodule extrudes conductive slurry to form a conductive layer and extrudes optical conductive material to form an optical signal transmission layer in the die assembly 13;

[0107] The precision coating component 212 for soft touch materials sprays a two-component TPO soft touch material onto the surfaces of the decorative texture and functional layer;

[0108] The core punch assembly 141 is transferred to the second injection station;

[0109] The core punch assembly 141 and the die assembly 13 are closed, and the multi-material injection molding unit performs injection molding to obtain the finished car dashboard.

[0110] Example 9 includes the following detailed steps:

[0111] Step 1: The industrial control computer 4 controls the electric turntable 142 to rotate, and moves the core punch assembly 141 to the first injection station. The lifting electric cylinder 143 drives the core punch assembly 141 to descend. The vision positioning module 214 takes pictures of the inner wall of the cavity and feeds back the position deviation to the robotic arm 213.

[0112] Step 2: The robotic arm 213 carries the plasma surface activation component 215 into the cavity between the concave mold component 13 and the core convex mold component 141, and sprays a mixed plasma of argon and carbon dioxide to perform a full-area scanning process on the inner wall of the cavity.

[0113] Step 3: Switch to the UV inkjet sub-module and perform inkjet printing on the cavity surface of the concave mold assembly 13 according to the preset pattern. Simultaneously, print hidden textures in the corresponding area of ​​the core convex mold assembly 141. After completion, the robotic arm 213 is equipped with a UV lamp to cure the texture.

[0114] Step 4: The robotic arm 213 switches to the functional material extrusion submodule, extruding conductive slurry in the design area of ​​the die assembly 13 to form a conductive layer; and extruding optical conductive material in the edge area of ​​the dashboard to form an optical signal transmission layer.

[0115] Step 5: The robotic arm 213 switches to the soft touch material precision coating assembly 212 and sprays a two-component TPO soft touch material onto the decorative texture and functional layer surfaces.

[0116] Step 6: The lifting cylinder 143 drives the core punch assembly 141 to rise, and the electric turntable 142 rotates to transfer the core punch assembly 141 to the second injection molding station.

[0117] Step 7: The lifting electric cylinder 143 drives the core punch assembly 141 and the die assembly 13 to close, and the multi-material injection molding unit and the intelligent temperature control module operate to perform injection molding to obtain the finished car dashboard.

[0118] Example 10: A Z-axis micro-compensation mechanism is added to the end of the robotic arm 213. Based on the cavity depth deviation fed back by the vision positioning module, the distance between the extrusion head and the cavity surface is dynamically adjusted. The specific method of dynamic adjustment is as follows: based on the filtered deviation value, the distance of the extrusion head to be adjusted is calculated, and a compensation coefficient is introduced to avoid overshoot.

[0119] ;

[0120] in It is the distance between the extruder head and the cavity surface that is dynamically adjusted. It is the target distance between the extruder head and the cavity surface. It is a correction factor used to balance sensitivity and stability. It is the average value of the depth deviation of the concave model cavity reported by the visual positioning module in the last n times.

[0121] By adopting the above technical solution and combining it with the K-value anti-overshoot design, the final extruder head distance fluctuation is controlled within ±0.005mm, the corresponding conductive layer thickness deviation is less than 0.03mm, and the surface resistance uniformity error is less than 3%, which meets the conductive function requirements of automotive dashboards.

[0122] Because of the stable distance, the material flow rate is uniform during extrusion, the optical signal transmission layer has high light transmittance and a thickness deviation of less than 0.02mm, ensuring that the optical signal is transmitted without attenuation at the edge of the instrument panel.

[0123] This avoids slurry accumulation due to excessively close spacing or slurry gaps due to excessively far spacing, significantly improving the one-time molding pass rate of functional layers.

[0124] In Example 11, step 7, injection molding includes the following sub-steps:

[0125] Step 71: The injection molding machine 221 starts plasticizing, heats the injection molding material to melt, and injects the melt into the tree-shaped distribution channel of the core punch assembly 141 through the delivery pipe 223, and finally fills the mold cavity radially from multiple distribution ports.

[0126] Step 72: After the melt fills the cavity, the injection molding machine 221 switches to the holding pressure mode and continues for a set time. The intelligent temperature control module keeps the core punch assembly 141 and the die assembly 13 at the set temperature.

[0127] Step 73: After the heat preservation and pressure holding are completed, the industrial control computer 4 instructs the intelligent temperature control module to switch to the cooling mode. After cooling, the lifting electric cylinder 143 drives the core punch assembly 141 to rise and separate from the die assembly 13, and remove the finished car dashboard.

[0128] The following specific embodiments illustrate the implementation principle of the present invention:

[0129] The central control dashboard of a certain new energy vehicle needs to integrate carbon fiber decorative texture, touch-sensitive function, ambient lighting guide strips, and zoned soft touch layers. The dashboard is injection molded using a multi-material co-injection molding automotive dashboard molding system. Specific parameters and processes are as follows:

[0130] System composition and initialization:

[0131] Multi-station rotary mold platform:

[0132] It contains 4 injection molding stations: pretreatment / decoration station, functional layer molding station, main injection station, and cooling and part removal station, which are evenly distributed around the injection platform 11 (at 90° intervals).

[0133] Die assembly 13: Made of P20 mold steel, with a cavity surface roughness of Ra0.8μm and built-in partitioned temperature control flow channel; Core punch assembly 141 is made of 718H mold steel with chrome plating, and is connected to lifting electric cylinder 143 through a positioning pin + electromagnetic locking quick-release structure.

[0134] Rotary lifting drive device: electric turntable 142, lifting electric cylinder 143 with a stroke of 150mm.

[0135] Multi-material injection molding unit:

[0136] Multifunctional surface forming device 21: robotic arm 213, equipped with vision positioning module 214, two 5-megapixel industrial cameras and laser contour sensor; plasma surface activation component 215; UV inkjet sub-module; functional material extrusion sub-module; soft touch material precision coating component 212.

[0137] Main injection unit 22: injection molding machine 221; conveying pipe 223; injection outlet / punch inlet rotary joint.

[0138] Four sets of circulating fluid temperature control devices (flow rate 0-50L / min, temperature control range 20-200℃); temperature detection module (PT100 sensor + infrared thermometer, accuracy ±0.1℃); temperature controller (PID regulation, response time <1s).

[0139] Industrial control computer 4 communicates with each module via Ethernet and is pre-installed with a process management system.

[0140] II. Molding process:

[0141] Step 1: System Initialization:

[0142] The industrial control computer 4 completes a self-test within 30 seconds of startup, confirming that all modules are fault-free; it then calls the process parameter package for the new energy vehicle dashboard, including:

[0143] Pretreatment temperature: Die / Punch 80±5℃;

[0144] Injection molding parameters: PP-LGF30 melt temperature 240℃, injection pressure 90bar, holding time 6s; Soft contact layer parameters: A / B component ratio 10:1 (master area) / 11:1 (passenger area), coating thickness 0.6mm / 0.8mm.

[0145] Step 2: Plasma activation:

[0146] The electric turntable 142 rotates the core punch assembly 141 to the work station, and the lifting electric cylinder 143 drives it to descend to a distance of 13-150mm from the die assembly; the vision positioning module 214 scans the cavity, provides feedback on the position deviation, and the robotic arm 213 automatically compensates for it.

[0147] Plasma surface activation component 215 is started: power 600W, scanning speed 80mm / s, and full cavity processing in 1.5s; after processing, the surface oil removal rate is 99%, and the surface energy reaches 75mN / m.

[0148] Step 3: UV decorative texture printing:

[0149] The UV inkjet submodule uses black polyurethane UV ink to print carbon fiber texture on the surface of the concave mold assembly 13-1 with a thickness of 0.03mm; at the same time, the model identification is printed on the inside of the core convex mold assembly 141.

[0150] UV-LED lamp irradiation for 2 seconds, energy density 900mJ / cm², texture curing degree greater than 95%, no sagging. Step 4: Functional layer molding:

[0151] The electric turntable 142 rotates to the workstation, and the robotic arm 213 switches to the functional material extrusion sub-module: conductive layer: silver nano-slurry is extruded in the steering wheel area of ​​the die assembly 13-2 to form a 0.1mm thick conductive circuit.

[0152] Optical transmission layer: Transparent silicone is extruded at the edge of the dashboard to form a 0.2mm thick light guide strip; the extrusion temperature is 120℃ to avoid damaging the UV texture.

[0153] Step 5: Applying the soft touch layer:

[0154] Robotic arm 213 switches to soft-touch material precision coating assembly 212:

[0155] Driver's area: Apply two-component TPO at a 10:1 ratio, with a thickness of 0.6mm;

[0156] Passenger area: Sprayed at an 11:1 ratio, 0.8mm thick;

[0157] Ultrasonic atomization pressure 0.3MPa, coating speed 40mm / s, infrared preheating 60℃ to ensure uniform spreading. Step 6: Transfer to injection molding station:

[0158] The lifting electric cylinder 143 drives the core punch assembly 141 to rise 100mm, the electric turntable 142 rotates 90° to the work position, and the die assembly 13-3 has been preheated to 120℃.

[0159] Step 7: Mold Closure and Injection Molding

[0160] The lifting electric cylinder 143 drives the core punch assembly 141 to descend and close the mold, and the punch inlet rotary joint 224 seals and connects with the core punch injection port.

[0161] Sub-step 71: The injection molding machine 221 heats PP-LGF30 to 240°C and injects it into the core punch tree-shaped flow channel through the delivery pipe 223, radiating and filling the cavity.

[0162] Sub-step 72: After the melt is filled, maintain pressure for 6 seconds. The intelligent temperature control module will keep the temperature of the punch at 150°C, the edge of the die at 140°C, and the center at 120°C.

[0163] Sub-step 73: After the pressure holding is completed, the circulating liquid temperature control device introduces 25°C cold water, which reduces the cavity temperature to 40°C within 10 seconds; the lifting electric cylinder 143 drives the punch to rise, and the robot picks up the part.

[0164] Step 8: Cooling and Testing

[0165] The product is transferred to the workstation, and 3D vision inspection shows:

[0166] The decorative texture has a clarity of 1200dpi and is defect-free.

[0167] The thickness deviation of the soft touch layer is ±0.02mm, and the hardness meets the standard;

[0168] The conductive layer has good conductivity, and the brightness deviation of the light guide strip is less than 3%.

[0169] Production efficiency: 52s per cycle, a 65% improvement over the traditional process (150s), and a 40% reduction in equipment footprint. Product quality: 0.3% appearance defect rate, 9N / cm soft contact layer bonding strength, 85MPa skeleton bending strength, and 0.4mm / m warpage.

[0170] Material costs: Eliminating IMD film and adhesive reduces costs by 18%, and the scrap recycling rate is 92%.

[0171] Flexible production: mold change time is 12 minutes, and it can be compatible with the production of dashboards for 8 different car models.

[0172] This embodiment verifies the feasibility of the technical solution in the production of complex function dashboards, achieving efficient, high-quality, and low-cost integrated molding.

[0173] The above are all preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Therefore, all equivalent changes made in accordance with the structure, shape and principle of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A multi-material co-injection molding system for automotive dashboards, characterized in that: The system includes a multi-station rotary mold platform, a multi-material injection unit, and an intelligent temperature control module. The multi-station rotary mold platform includes an injection platform (11), multiple injection stations (12), multiple cavity mold assemblies (13), and a rotating core punch assembly (14). The multiple injection stations (12) are respectively installed on the injection platform (11), and the multiple cavity mold assemblies (13) are respectively installed on the multiple injection stations (12). The rotating core punch assembly (14) includes a rotary lifting drive device and a core punch assembly (141). The rotary lifting drive device is located above the injection platform (11), and the core punch assembly (141) is detachably installed on the rotary lifting part of the rotary lifting drive device. The multi-material injection molding unit includes a multi-functional surface forming device (21) and a main injection device (22). The soft-touch layer forming device (22) is used to spray a multi-functional decorative layer on the inner wall of the cavity of the cavity assembly (13) and the core punch assembly (141) before the injection molding action. The main injection device (22) is connected to the core punch assembly (141). The injection action is performed after the core punch assembly (141) is docked with the cavity assembly (13). The intelligent temperature control module controls the temperature of the mold cavity formed after the core punch assembly (141) and the die assembly (13) are connected.

2. The automotive dashboard molding system based on multi-material co-injection molding according to claim 1, characterized in that: The multi-functional surface forming device (21) includes a multi-modal adaptive printing component (211) and a soft-touch material precision coating component (212). The multi-modal adaptive printing component (211) includes a UV inkjet sub-module and a functional material extrusion sub-module. The UV inkjet sub-module is used to spray decorative textures on the inner walls of the cavity of the die component (13) and the core punch component (141). The functional material extrusion sub-module is used to print functional layers, including conductive layers and optical signal transmission layers. The soft-touch material precision coating component (212) uses an ultrasonic vibration atomizing nozzle to spray TPO soft-touch base material onto the cavity surface after being sprayed by the UV inkjet sub-module.

3. The automotive dashboard molding system based on multi-material co-injection molding according to claim 2, characterized in that: The multifunctional surface forming device (21) also includes a robotic arm (213), a vision positioning module (214), and a plasma surface activation component (215). The base of the robotic arm (213) is installed on one side of the multi-station rotary mold platform. The nozzles of the modal adaptive printing component (211) and the soft-touch material precision coating component (212) are respectively installed on the movable end of the robotic arm (213). The vision positioning module (214) is installed on the movable end of the robotic arm (213) and is used to visually identify and position the cavity position of the concave mold component (13) and the core punch component (141). The plasma surface activation component (215) is installed at the movable end of the robotic arm (213) and performs low-temperature plasma treatment on the cavity surfaces of the die assembly (13) and the core punch assembly (141) before the modal adaptive printing component (211) and the soft-touch material precision coating component (212) move.

4. The automotive dashboard molding system based on multi-material co-injection molding according to claim 3, characterized in that: The main injection molding device (22) includes an injection molding machine (221), an injection outlet rotary joint (222), a conveying pipe (223), and a punch inlet rotary joint (224). One end of the conveying pipe (223) is connected to the molten material outlet of the injection molding machine (221) through the injection outlet rotary joint (222), and the other end is connected to the injection port of the core punch assembly (141) through the punch inlet rotary joint (224).

5. The automotive dashboard molding system based on multi-material co-injection molding according to claim 4, characterized in that: The rotary lifting drive device includes an electric turntable (142) and a lifting cylinder (143). The base of the electric turntable (142) is mounted on a bracket (100). The cylinder body of the lifting cylinder (143) is detachably mounted on the rotating part of the electric turntable (142) and rotates with the rotating part. The piston rod of the lifting cylinder (143) faces the injection molding station (12). The core punch assembly (141) is detachably mounted on the end of the piston rod of the lifting cylinder (143). When the electric turntable (142) and the lifting cylinder (143) move, the core punch assembly (141) is docked to achieve mold closing.

6. The automotive dashboard molding system based on multi-material co-injection molding according to claim 5, characterized in that: The intelligent temperature control module includes multiple sets of circulating fluid temperature control devices, a temperature detection module, and a temperature controller. The multiple concave mold components (13) and the core punch component (141) are all provided with temperature control channels. The circulating fluid inlets and outlets of the multiple sets of circulating fluid devices are respectively connected to the temperature control channels of the multiple concave mold components (13) and the core punch component (141). The temperature detection module collects the internal temperature of the multiple concave mold components (13) and the core punch component (141). The temperature controller is communicatively connected to the temperature detection module and controls the execution actions of the multiple sets of circulating fluid temperature control devices based on the temperature monitoring data and the set temperature control data. It also includes an industrial control computer (4), which controls the execution actions of each actuator of the multi-station rotary mold platform, the multi-material injection molding unit and the intelligent temperature control module.

7. A method for molding automotive dashboards based on multi-material co-injection molding, characterized in that: The automotive dashboard injection molding process using the multi-material co-injection molding system described in claim 6 includes the following steps: Step 1: Inject a mixed plasma of argon and carbon dioxide into the inner wall of the cavity; Step 2: Inkjet printing is performed on the cavity surface of the die assembly (13), and hidden textures are simultaneously printed in the corresponding area of ​​the core punch assembly (141). Step 3: Extruding conductive slurry to form a conductive layer and extruding optical conductive material to form an optical signal transmission layer in the die assembly (13); Step 4: Spray a two-component TPO soft touch material onto the decorative texture and functional layer surfaces; Step 5: The core punch assembly (141) is transferred to the second injection molding station; Step 6: The multi-material injection molding unit performs injection molding to obtain the finished car dashboard.

8. The automotive dashboard molding method based on multi-material co-injection molding according to claim 7, characterized in that, The following detailed steps are included: Step 1: The industrial control computer (4) controls the electric turntable (142) to rotate and transfer the core punch assembly (141) to the first injection station. The lifting electric cylinder (143) drives the core punch assembly (141) to descend. The vision positioning module (214) takes pictures of the inner wall of the cavity and feeds back the position deviation to the robotic arm (213). Step 2: The robotic arm (213) carries the plasma surface activation component (215) into the cavity between the concave mold component (13) and the core punch component (141), and sprays a mixed plasma of argon and carbon dioxide to perform a full-area scanning process on the inner wall of the cavity. Step 3: Switch to the UV inkjet sub-module and perform inkjet printing on the cavity surface of the concave mold assembly (13) according to the preset pattern. Simultaneously, print hidden textures in the corresponding area of ​​the core convex mold assembly (141). After completion, the robotic arm (213) is equipped with a UV lamp to cure the texture. Step 4: The robotic arm (213) switches to the functional material extrusion submodule, extrudes conductive slurry in the design area of ​​the die assembly (13) to form a conductive layer; and extrudes optical conductive material in the edge area of ​​the dashboard to form an optical signal conductive layer. Step 5, the robotic arm (213) switches to the soft touch material precision coating assembly (212) to spray a two-component TPO soft touch material onto the decorative texture and functional layer surfaces; Step 6: The lifting electric cylinder (143) drives the core punch assembly (141) to rise, and the electric turntable (142) rotates to transfer the core punch assembly (141) to the second injection molding station. Step 7: The lifting electric cylinder (143) drives the core punch assembly (141) and the die assembly (13) to close, and the multi-material injection molding unit and the intelligent temperature control module perform injection molding to obtain the finished car dashboard.

9. The automotive dashboard molding method based on multi-material co-injection molding according to claim 8, characterized in that, A Z-axis micro-compensation mechanism is added to the end of the robotic arm (213). Based on the depth deviation of the concave mold cavity fed back by the vision positioning module, the distance between the extrusion head and the surface of the cavity is dynamically adjusted. The specific method of dynamic adjustment is as follows: based on the filtered deviation value, the distance of the extrusion head to be adjusted is calculated, and a compensation coefficient is introduced to avoid overshoot. ； in It is the distance between the extruder head and the cavity surface that is dynamically adjusted. It is the target distance between the extruder head and the cavity surface. It is a correction factor used to balance sensitivity and stability. It is the average value of the depth deviation of the concave model cavity reported by the visual positioning module in the last n times.

10. The automotive dashboard molding method based on multi-material co-injection molding according to claim 9, characterized in that: Step 7, injection molding includes the following sub-steps: Step 71: The injection molding machine (221) starts plasticizing, heats the injection molding material to melt, and injects the melt into the tree-shaped distribution channel of the core punch assembly (141) through the delivery pipe (223), and finally fills the mold cavity radially from multiple distribution ports. Step 72: After the melt fills the cavity, the injection molding machine (221) switches to the holding pressure mode and continues for a set time. The intelligent temperature control module keeps the core punch assembly (141) and the die assembly (13) at the set temperature. Step 73: After the heat preservation and pressure preservation are completed, the industrial control computer (4) instructs the intelligent temperature control module to switch to the cooling mode. After cooling, the lifting electric cylinder (143) drives the core punch assembly (141) to rise and separate from the die assembly (13) to remove the finished car dashboard.

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