Environment-friendly plastic product in-mold coating processing equipment and process

Abstract

The invention discloses environment-friendly plastic product in-mold coating processing equipment which comprises an in-mold coating device, a color paste conveying device, a mixing head and a forming mold, the in-mold coating device comprises an A material tank used for supplying A materials and a B material tank used for supplying B materials, and the color paste conveying device comprises a C material tank used for supplying C materials; the material A, the material B and the material C are mixed in the mixing head to form a reaction forming coating, and the discharging end of the mixing head is connected with the coating feeding end of the forming mold. The environment-friendly plastic product in-mold coating processing equipment is high in equipment integration degree, capable of reducing processing procedures, stable, flexible and convenient to operate, capable of obtaining high-quality product surfaces with various color effects and capable of being flexibly and freely matched with different types of injection molding machines and turnover mold frame equipment according to the production requirements of customers, and the production efficiency is improved. And the production requirements of customers in different application scenes can be met.

Description

Technical Field

[0001] The invention relates to the technical field of plastic molding, and in particular to an environmentally friendly in-mold coating processing equipment and process for plastic products. Background Art

[0002] The painting process is mostly used for the coating of plastic products. The existing painting devices are mostly used because the nozzles are relatively fixed, so the spraying range is limited and the surface of the plastic products cannot be completely covered. The problem of uneven spraying is prone to occur, resulting in poor paint spraying effect and low yield. During the spraying process, the paint scattered on the workbench or in the workshop will seriously pollute the workshop environment and is not easy to clean. For high-end plastic products, the process usually requires multiple steps and the processing efficiency is low.

[0003] The existing technology has made improvements to the defects of poor quality of finished products and environmental pollution in the painting process. For example, the Chinese patent CN213222874U discloses a painting device for automobile grille production and processing: the horizontal position, height and rotation of the spray head are adjusted by the mutual cooperation between the first electric telescopic rod, the motor, the third gear, the second electric telescopic rod and the square rod, the working arm and other components, and the scattered paint is collected by the storage box and the groove, which solves the problem that the existing painting device is prone to uneven spraying and the paint scattered on the workbench or in the workshop during the spraying process seriously pollutes the workshop environment and is difficult to clean. However, the technical solution disclosed by CN213222874U still has cumulative errors in the process of adjusting the various components of the painting device, and the thickness and accuracy of the paint will deviate, thereby affecting the quality of the product painting; the above technical solution only adds a storage box and a groove, and only collects the scattered paint, and does not fundamentally solve the pollution source of the workshop.

[0004] In-mold injection molding surface decoration processing technology is mainly used for surface decoration and functional panels of interior and exterior decoration in the automotive industry and home appliances. Since large films are prone to local rupture or deformation during deep cavity or special-shaped forming, the shape and position accuracy of surface patterns or text is low, so it is difficult to apply it to large, deep cavity, special-shaped parts (such as laptop panels, car interior parts and other products). Since large films are difficult to position in the mold and the operation is cumbersome, it takes a lot of debugging time, resulting in low production efficiency and limited application scenarios.

[0005] The existing technology has made improvements to the defect that the in-mold injection molding surface decoration processing technology is difficult to apply to large films. For example, Chinese patent CN108727797A discloses a polycarbonate substrate for in-mold decoration and its preparation method: by blending branched polycarbonate with copolyester, the thermal tensile deformation and puncture resistance of polycarbonate are increased, and the application of polycarbonate film on large deep cavities and special-shaped parts is realized. However, the technical solution disclosed in CN108727797A still has positioning errors in the process of installing polycarbonate film due to the need for installation and positioning; the substrate of the above technical solution is limited to modified and optimized polycarbonate material, and the product substrate selection has limitations; the large film of the above technical solution is prone to local rupture or deformation during the forming process, resulting in low shape and position accuracy and fuzziness of the surface pattern and text of the product.

[0006] The reaction molding in-mold coating process can, to a certain extent, overcome the shortcomings of the spray painting process and the in-mold injection molding surface decoration process, such as poor product quality, environmental pollution, and difficulty in applying to large films. Usually, the raw material product (substrate product) is injection molded first, and then the raw material product is transported and transferred to the second PU layer process for processing.

[0007] The prior art reaction molding in-mold coating processing technology, for example, Chinese patent CN110978387A discloses a multi-material injection molding machine and a multi-material injection molding method thereof: during processing, the first mold is closed to inject the injection molded part a; the first mold is opened to move the injection molded part a to the first PU fixed mold seat; the second mold is closed to perform PU layer injection molding on the injection molded part a and inject the injection molded part b; the second mold is opened to move the injection molded part b to the second PU fixed mold seat; the third mold is closed to perform PU layer injection molding on the injection molded part b and inject the injection molded part a'; the third mold is opened to take out the injection molded part a from the first PU fixed mold seat and move the injection molded part a' to the first PU fixed mold seat. The technical solution disclosed in CN110978387A requires that, during the process of applying a polyurethane coating on the surface of an injection molding substrate, the position of the injection molding substrate needs to be transferred from the original position A to the position B, and from one fixed mold cavity to another fixed mold cavity, with a process of alternating substrate conversion in the middle. Due to the need to perform secondary positioning of the product, there will be positioning errors; the polyurethane casting equipment is connected to the polyurethane fixed mold seat and is arranged on the front template, the injection molded part needs to be clamped on the fixed mold seat by a fixture, and a tooling fixture needs to be set on the mold; the many process links lead to complex equipment operation and low production efficiency; this solution requires that the PU fixed mold seat be connected to a compressed air source, and the compressed air source is used to pass compressed air through the PU fixed mold. In order to ensure the molding effect of the PU layer in the PU fixed mold seat, compressed air needs to be injected into the PU fixed mold seat before injecting the PU. This solution will increase production time and affect efficiency, as well as increase the investment in auxiliary equipment for vacuuming and passing compressed air. In addition, the technical solution disclosed in CN110978387A requires connecting the PU fixed mold seat to a compressed air source, which is used to pass compressed air through the PU fixed mold. In order to ensure the molding effect of the PU layer in the PU fixed mold seat, compressed air needs to be injected into the PU fixed mold seat before injecting the PU. This solution will increase production time and affect efficiency, as well as increase the investment in auxiliary equipment for vacuuming and passing compressed air.

[0008] The existing technology of reaction molding in-mold coating processing technology still has the problem of single color of PU surface layer, and there are few product colors for customers to choose from. The addition of color paste in the PU material tank will cause a lot of time to be spent on subsequent color switching, affecting production efficiency.

[0009] In summary, although the reaction molding in-mold coating process in the prior art can overcome some technical defects of the spray painting process and the in-mold injection molding surface decoration process, it still has the defects of complicated production process, low efficiency, large number of production equipment and auxiliary machines, large factory space, high investment cost and single product color. Summary of the invention

[0010] In order to solve one or more technical problems in the prior art, the present invention provides an environmentally friendly in-mold coating processing equipment for plastic products.

[0011] An environmentally friendly in-mold coating processing equipment for plastic products, comprising an in-mold coating device, a color paste conveying device, a mixing head and a molding mold, wherein the in-mold coating device comprises an A material tank for supplying A material and a B material tank for supplying B material, the color paste conveying device comprises a C material tank for supplying C material, the A material, the B material and the C material are mixed inside the mixing head to form a reaction molding coating, and the discharge end of the mixing head is connected to the coating feed end of the molding mold;

[0012] The A material tank is connected to the feed port A of the mixing head through the discharge pipe A and the reflux pipe A;

[0013] The B material tank is connected to the feed port B of the mixing head through the discharge pipe B and the return pipe B;

[0014] The C material tank is connected to the feed port C of the mixing head through the discharge pipe C and the reflux pipe C;

[0015] The mixing head is provided with a cleaning rod and a control rod, the cleaning rod is used to clean the paint residue in the mixing head and block the discharge port of the mixing head, and the control rod is used to block or open the feed port A, the feed port B and the feed port C;

[0016] When the control lever is in the closed position: the A material can circulate in the A material tank, the discharge pipe A and the return pipe A, the B material can circulate in the B material tank, the discharge pipe B and the return pipe B, and the C material can circulate in the C material tank, the discharge pipe C and the return pipe C.

[0017] Preferably, the A material tank, the B material tank and the C material tank are all connected to a temperature control device, and the temperature control device includes a water-type raw material temperature controller, and the water-type raw material temperature controller is connected to a jacketed heat exchanger arranged outside the A material tank and the B material tank through a water pipeline, and the jacketed heat exchanger is provided with a heat insulation layer outside.

[0018] Preferably, the A material tank and the B material tank are both connected to a raw material agitator, and the raw material agitator can stir continuously or indirectly.

[0019] Preferably, the A material tank and the B material tank are both connected to a low-pressure feeding pump, and the two low-pressure feeding pumps are respectively connected to different high-pressure metering pumps through pipelines.

[0020] Preferably, the high-pressure metering pump is arranged in a heat-insulating box, and a volume flow meter is also arranged in the heat-insulating box, and the volume flow meter is connected to the high-pressure metering pump through a pipeline.

[0021] Preferably, both the A material tank and the B material tank are connected to a vacuum generator.

[0022] Preferably, the mixing head is connected to a hydraulic power station, and the cleaning rod and the control rod are telescopically moved by hydraulic power provided by the hydraulic power station.

[0023] Preferably, the A material tank, the B material tank and the hydraulic power station are all installed on bracket one, and the bracket one is also provided with an AB material electric control cabinet and AB material automatic feeding equipment.

[0024] Preferably, the color paste conveying device is arranged on a color paste station bracket.

[0025] Preferably, the environmentally friendly in-mold coating processing equipment for plastic products also includes an injection molding device, and the injection molding device is provided with an automatic plastic feeding device, a hopper and a raw material drying system.

[0026] Preferably, the molding die includes a slide die plate and a fixed die plate;

[0027] The slide template is provided with two half-molds, half-mold 1 and half-mold 2, and the fixed template is provided with half-mold 3. The half-mold 1 and the half-mold 2 can be switched to dock with the half-mold 3 by translation and sliding;

[0028] The half mold three is connected to the discharge end of the injection molding device and the discharge end of the mixing head;

[0029] The first half mold and the third half mold are molded together to form an injection molding substrate cavity;

[0030] The second half mold and the third half mold are molded together to form a reaction molding coating cavity.

[0031] Preferably, the molding die includes a movable die plate and a front die plate;

[0032] The movable platen is provided with a rotating mechanism that can rotate 360° along the vertical axis, and the movable platen is also provided with a horizontal movement mechanism, and the movable platen includes a first half mold and a second half mold;

[0033] The front template is provided with a horizontal moving mechanism, and the front template comprises a third half-mold and a fourth half-mold;

[0034] The third half mold is connected to the discharge end of the injection molding device, and the first half mold and the second half mold can be combined with the third half mold to form an injection molding substrate cavity;

[0035] The fourth half mold is connected to the discharge end of the mixing head, and the first half mold and the second half mold can be molded together with the fourth half mold to form a reaction molding coating cavity.

[0036] Preferably, an automatic pick-up device for taking out the workpiece from the forming mold is provided on one side of the forming mold, and an automatic trimming device for trimming the workpiece is provided on one side of the automatic pick-up device, and the automatic pick-up device and the automatic trimming device are both arranged in an automated isolation fence.

[0037] Preferably, the number of the C material tanks is two or more.

[0038] Preferably, the environmentally friendly in-mold coating processing equipment for plastic products is controlled by input and output logic of digital signals, and the control logic of the digital signals includes one or more of the following:

[0039] D1. When the environmentally friendly plastic product in-mold coating processing equipment fails, a "DO mechanical failure" signal is output;

[0040] D2. When the mold half 1 and the mold half 3 are combined to form a mold cavity for the injection molded substrate, the "DO cleaning rod advances" signal is output, and the output is disconnected before the "DO ready to foam" signal is output; after the cleaning rod advances to the right position, the system outputs the "DI cleaning rod advances to the right position" signal, and the "DI cleaning rod advances to the right position" signal is effective at a high level;

[0041] D3. When the environmentally friendly plastic product in-mold coating processing equipment is in semi-automatic / fully automatic mode, a "DO automatic operation" signal is output;

[0042] D4. When the reaction molding coating cavity is formed after mold closing, the "DO ready to foam" signal is triggered, and the "DO ready to foam" signal is disconnected before the "DO start foaming" signal is output;

[0043] D5. When the system receives the "DI ready for foaming" signal, it outputs the "DO start foaming" signal; when the system receives the "DI foaming completed" signal, it disconnects the "DO start foaming" signal output and enters the foaming cooling timing, and the "DI foaming completed" signal is valid at a high level; the "DI ready for foaming" signal is valid at a high level, and the "DO start foaming" signal output is prohibited if no high-level signal is received; the "DI foaming completed" signal is valid at a high level;

[0044] D6. When the foaming machine is foaming, the system outputs a "DI is foaming" signal. The "DI is foaming" signal is effective at a high level, and no alarm is output;

[0045] D7. Trigger the "DO cleaning rod blowing" signal through the "DI foaming completed" signal;

[0046] D8. When the foaming machine fails, the system outputs a "DI foaming machine failure" signal. The "DI foaming machine failure" signal is effective at a high level. When the "DI foaming machine failure" signal is input into the system, the system alarms "foaming machine failure" and prohibits the system from entering the automatic mode with "foaming action". If in the automatic mode, it jumps to the manual mode after the cycle ends;

[0047] D9. When the downstream equipment of the injection molding machine detects unqualified products, a "DI product unqualified" signal is input to the system, and the high level of the "DI product unqualified" signal is valid.

[0048] In order to solve one or more technical problems in the prior art, the present invention also provides an environmentally friendly in-mold coating process for plastic products.

[0049] An environmentally friendly in-mold coating process for plastic products, the environmentally friendly in-mold coating process equipment for plastic products comprises the following steps:

[0050] S01. Mold closing, at which time the first half mold and the third half mold are closed to form an injection molding substrate cavity for the first workpiece, and the injection molding device injects the first workpiece substrate into the injection molding substrate cavity;

[0051] S02. Maintain the mold, and perform pressure holding and cooling of the first workpiece substrate;

[0052] S03. Open the mold, attach the first workpiece substrate to the first half mold, and close the mold after the movable mold plate rotates 180 degrees. At this time, the first half mold and the fourth half mold are closed to form a reaction molding coating cavity with the first workpiece substrate built in, and the second half mold and the third half mold are closed to form an injection molding substrate cavity for the second workpiece;

[0053] S04. Keeping the mold closed, the mixing head injects the reaction molding coating onto the surface of the first workpiece substrate, while the injection molding device simultaneously injects the second workpiece substrate;

[0054] S05. Keep the mold closed, while the reaction molding coating is reacting and molding on the surface of the first workpiece substrate, the second workpiece substrate is simultaneously pressurized and cooled;

[0055] S06. Open the mold, attach the first workpiece that has been painted to the first half mold, attach the second workpiece substrate to the second half mold, and remove the first workpiece that has been painted from the first half mold by the automatic removal device;

[0056] S07. After the movable mold plate rotates 180°, the second mold half and the fourth mold half are molded together to form a reaction molding coating cavity with a second workpiece substrate built in, and the first mold half and the third mold half are molded together to form an injection molding substrate cavity for the third workpiece;

[0057] S08. Keeping the mold closed, the mixing head injects the reaction molding coating onto the surface of the second workpiece substrate, while the injection molding device simultaneously injects the third workpiece substrate;

[0058] S09. The mold is kept closed, and while the reaction molding coating is reacting and molding on the surface of the second workpiece substrate, the pressure holding and cooling of the third workpiece substrate are carried out simultaneously;

[0059] S010. Open the mold, attach the painted second workpiece to the second half mold, attach the third workpiece substrate to the first half mold, and remove the painted second workpiece from the second half mold by the automatic removing device.

[0060] Preferably, the injection molding substrate material of the injection molding device includes one or more of polypropylene, PC, ABS, PC+ABS, PA66 and carbon fiber.

[0061] Preferably, when the reaction molding coating is polyurethane and the molding mold includes the movable mold plate and the front mold plate, the melting temperature of the barrel of the injection molding device is 200°C to 320°C, the mold temperatures of the first half mold, the second half mold and the third half mold are 80°C to 110°C, the mold temperature of the fourth half mold is 90°C to 130°C, the temperature of the polyurethane material entering the reaction molding coating cavity is 60°C to 90°C, the working pressure of the polyurethane material entering the reaction molding coating cavity is 11MPa to 21MPa, and the curing time of the polyurethane material in the reaction molding coating cavity is 20s to 200s.

[0062] Preferably, the injection molding substrate material is polypropylene, the melting temperature of the barrel of the injection molding device is 170° C. to 250° C., the injection molding substrate is a polypropylene substrate, and the in-mold coating process of the polypropylene substrate comprises the following steps:

[0063] S11. The injection molding device injects a polypropylene substrate into the injection molding substrate cavity;

[0064] S12. The completed injection-molded polypropylene substrate is sent to the PLASMA surface treatment equipment model SPA2800 for plasma treatment by rotating the turntable;

[0065] S13. Injection molding of polyurethane material on the surface of the plasma-treated polypropylene substrate;

[0066] S14. Open the mold and take out the finished product with polypropylene and polyurethane materials bonded together.

[0067] Preferably, the technical parameters of the PLASMA surface treatment equipment are: voltage 190V-250V, frequency 40HZ-60HZ, current 0.25A-0.35A, air pressure 0.4bar-0.8bar, and treatment width 20-90mm.

[0068] Preferably, the voltage is 220V, the frequency is 50HZ, the current is 0.31A, the air pressure is 0.6bar, and the processing width is 75mm.

[0069] Preferably, the technical parameters of the PLASMA surface treatment equipment are: the height of the plasma from the substrate surface is 8 mm to 15 mm, the plasma moving speed is 50 mm / s to 150 mm / s, and the plasma temperature is 70° C. to 100° C.

[0070] Preferably, the height of the plasma from the substrate surface is 10 mm, the plasma moving speed is 100 mm / s, and the plasma temperature is 90°C.

[0071] Beneficial effects of the present invention:

[0072] (1) The present invention can solve the technical problem of low production efficiency caused by complicated process technology and equipment in the prior art:

[0073] Chinese patent CN117382096A discloses the application of PUR film internal spray painting injection molding process in the production of interior car lights. The patent mentions that there are multiple color schemes to choose from, but does not disclose its methods. Chinese patent CN101400498A discloses a method and equipment for manufacturing multi-component plastic molded parts. The patent does not provide any inspiration for setting up a color paste conveying device, that is, those skilled in the art can only think of adding color paste pigments to the A material tank or the B material tank with reference to the patent scheme. When switching colors, it is necessary to clean the A material tank or the B material tank. This process is cumbersome and inefficient, and will cause material waste. However, this patent sets a color paste conveying device and sets the number of C material tanks to more than two. By switching the feed port C to connect with different C material tanks, the color of the reaction molding coating can be quickly switched, and there is no need to clean the material tank, which has high production efficiency, is environmentally friendly, and saves money.

[0074] Chinese patent CN114147915A discloses an in-mold spraying system and its process method. The patent moves the mold left and right, that is, first injects the substrate, then moves the mold to the PU cavity and then paints it, and then opens the mold and moves it to the substrate cavity to inject the substrate after painting. Only one single cavity can be produced each time. Based on the processing steps S01 to S010 provided by this patent, the produced substrate can be moved to the PU cavity first, painted and the substrate injection can be completed on the other side at the same time, and the production can be cyclically alternating, which greatly improves the efficiency.

[0075] The conventional processing method of the prior art is to first inject the material (substrate) product, and then transport and transfer the substrate to the mold for painting. This method has complicated procedures, resulting in low production efficiency and large product positioning errors. The present invention can effectively reduce the in-mold painting process by combining the reaction molding equipment and the injection molding equipment, and complete the painting process in the mold without demoulding, which can solve the problems of product deformation and positioning difficulties.

[0076] (2) The present invention can solve the technical problems that the prior art equipment occupies a large plant space, the equipment system integration is not high, and a large amount of auxiliary equipment is required:

[0077] In the prior art, the heating device and electrical control cabinet, material tank, and vacuum system are scattered. The equipment and system in the present invention are highly integrated and can effectively reduce the space occupied. The traditional two-step painting process requires a lot of auxiliary equipment. This patent is suitable for the one-step painting process, which can reduce the investment in auxiliary equipment and save the space occupied by equipment. The temperature control device of this patent adopts a nested water channel design for the material tank. The small water temperature control system occupies a small area and can reduce the space used in the hot air heating and large mold temperature controller heating devices used in the prior art. This patent integrates the vacuum generator on the material tanks of material A and material B respectively, which can reduce the space and investment in vacuum auxiliary equipment.

[0078] (3) The processing equipment and processing technology provided by the present invention are very environmentally friendly:

[0079] The spraying equipment in the prior art widely has defects such as large pollution, high energy consumption, multiple processes, and low efficiency. The present invention adopts a one-step coating molding process in the mold, which does not require multiple stations and paint, and perfectly matches the reaction molding coating. Compared with the prior art, the equipment and process of the present invention has the advantages of being more environmentally friendly, lower energy consumption, fewer processes, and higher efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0080] The accompanying drawings are used to provide further understanding of the present invention and constitute a part of the specification. They are used to explain the present invention together with the embodiments of the present invention and do not constitute a limitation of the present invention.

[0081] Figure 1 Schematic diagram of an environmentally friendly in-mold coating processing device for plastic products according to an embodiment of the present invention Figure 1 ;

[0082] Figure 2 Schematic diagram of an environmentally friendly in-mold coating processing device for plastic products according to an embodiment of the present invention Figure 2 ;

[0083] Figure 3 Schematic diagram of an environmentally friendly in-mold coating processing device for plastic products according to an embodiment of the present invention Figure 3 ;

[0084] Figure 4 Schematic diagram of an environmentally friendly in-mold coating processing device for plastic products according to an embodiment of the present invention Figure 4 ;

[0085] Figure 5 is a schematic diagram of a mixing head according to an embodiment of the present invention;

[0086] Figure 6 is a schematic diagram of connecting a material tank and a vacuum generator according to an embodiment of the present invention;

[0087] Figure 7 This is a photo of the undesirable phenomenon 1;

[0088] Figure 8 This is a photo of the second undesirable phenomenon;

[0089] Fig. 9 This is a photo of the third undesirable phenomenon;

[0090] Fig.10 This is a photo of the fourth undesirable phenomenon;

[0091] Fig.11 is an overview of a turntable mode I / O signal block diagram according to an embodiment of the present invention;

[0092] Fig.12 is an overview of a block diagram of a sliding table mode I / O signal according to an embodiment of the present invention;

[0093] Fig.13 is a logic diagram of processing of unqualified products by a system according to an embodiment of the present invention;

[0094] Fig.14 is a schematic diagram of an environmentally friendly in-mold coating process for plastic products according to an embodiment of the present invention;

[0095] Fig.15 is a schematic diagram of a mold texture according to an embodiment of the present invention;

[0096] Fig.16 Schematic diagram of an environmentally friendly in-mold coating processing device for plastic products according to an embodiment of the present invention Figure 5 ;

[0097] Fig.17 Schematic diagram of an environmentally friendly in-mold coating processing device for plastic products according to an embodiment of the present invention Figure 6 ;

[0098] Fig.18 Schematic diagram of an environmentally friendly in-mold coating processing device for plastic products according to an embodiment of the present invention Figure 7 ;

[0099] Fig.19Schematic diagram of an environmentally friendly in-mold coating processing device for plastic products according to an embodiment of the present invention Figure 8 ;

[0100] In the figure: 1. In-mold coating device; 101. A material tank; 1011. Discharge pipe A; 1012. Return pipe A; 102. B material tank; 1021. Discharge pipe B; 1022. Return pipe B; 103. Raw material agitator; 104. Low-pressure feeding pump; 105. Insulation box; 106. Vacuum generator; 2. Color paste conveying device; 201. C material tank; 2011. Discharge pipe C; 2012. Return pipe C; 3. Mixing head; 301. Feed port A; 302. Feed port B; 303. Feed port C; 304. Cleaning rod ; 305, control lever; 306, hydraulic power station; 4, molding mold; 401, first half mold; 402, second half mold; 403, third half mold; 404, fourth half mold; 5, temperature control device; 501, water-type raw material temperature controller; 601, bracket one; 6011, AB material electric control cabinet; 6012, AB material automatic feeding equipment; 602, bracket two; 7, injection molding device; 701, automatic feeding equipment; 8, automated isolation guardrail; 801, automatic pick-up device; 802, automatic trimming device; 9, centralized control system. DETAILED DESCRIPTION

[0101] The present invention is further described in detail below in conjunction with embodiments. The following embodiments are for explanation of the present invention but the present invention is not limited to the following embodiments.

[0102] Various embodiments according to the present invention will be described in detail below with reference to the accompanying drawings.

[0103] like Figures 1 to 19 As shown, an environmentally friendly in-mold coating processing equipment for plastic products includes an in-mold coating device 1, a color paste conveying device 2, a mixing head 3 and a molding mold 4, wherein the in-mold coating device 1 includes an A material tank 101 for supplying A material and a B material tank 102 for supplying B material, the color paste conveying device 2 includes a C material tank 201 for supplying C material, the A material, the B material and the C material are mixed inside the mixing head 3 to form a reaction molding coating, and the discharge end of the mixing head 3 is connected to the coating feed end of the molding mold 4;

[0104] In specific use, the preferred reaction forming coating of this patent is polyurethane (PUR), in which case material A is polyether polyol, material B is isocyanate, and material C is polyether polyol containing color paste / pigment. In addition to polyurethane, the reaction forming coating can also be polyurea (PUA) or other two-component or multi-component coatings.

[0105] The A material tank 101 is connected to the feed port A301 of the mixing head 3 through the discharge pipe A1011 and the return pipe A1012;

[0106] The B material tank 102 is connected to the feed port B302 of the mixing head 3 through the discharge pipe B1021 and the return pipe B1022;

[0107] The C material tank 201 is connected to the feed port C303 of the mixing head 3 through the discharge pipe C2011 and the return pipe C2012;

[0108] During specific design, the discharge pipe A1011, the reflux pipe A1012, the discharge pipe B1021, the reflux pipe B1022, the discharge pipe C2011, and the reflux pipe C2012 can all be configured as pipes with heating function.

[0109] The mixing head 3 is provided with a cleaning rod 304 and a control rod 305, the cleaning rod 304 is used to clean the paint residue in the mixing head 3 (mainly the paint residue in the mixing chamber of the mixing head 3 and the wall of the discharge pipe) and block the discharge port of the mixing head 3 (blocking the discharge port of the mixing head 3 can prevent the plastic substrate from entering the mixing head 3 during the injection molding operation), and the control rod 305 is used to block or open the feed port A301, the feed port B302 and the feed port C303;

[0110] When the control rod 305 is in the closed position: the A material can circulate in the A material tank 101, the discharge pipe A1011 and the return pipe A1012, the B material can circulate in the B material tank 102, the discharge pipe B1021 and the return pipe B1022, and the C material can circulate in the C material tank 201, the discharge pipe C2011 and the return pipe C2012.

[0111] like Figure 1 , 2 As shown in Figures 4 and 5, the main function and role of the mixing head 3 is that the material A and the material B pass through the control system of the in-mold coating device 1, respectively from the corresponding material tanks through the feeding pump to the high-pressure metering pump, and enter the mixing head 3 together with the material C flowing out of the color paste material tank (C material tank 201) according to the preset flow rate, pressure (such as 150 bar) and ratio and the specific pipeline with heating. The material A, the material B and the material C are mixed together in a turbulent manner in the mixing head 3. After mixing, they enter the mold from the flow channel and form a coating layer with a color effect on the surface of the substrate in the mold.

[0112] The main function and role of the cleaning rod 304 is to clean the PUR residual material in the mixing chamber of the in-mold mixing head and the wall of the discharge pipe.

[0113] The control rod 305 is controlled by hydraulic pressure to advance, and the function of the control rod 305 is to circulate the raw materials through the return groove of the control rod 305. More specifically, the control rod 305 may be provided with a self-sealing groove, and when the mixing head 3 is mixing, the raw materials are injected into the self-sealing groove on the control rod 305 for reaction and foaming, so that the gap between the control rod 305 in the mixing head 3 and the inner wall of the mixing head is sealed to prevent the raw materials from flowing.

[0114] In the specific design, by setting a return groove (key groove) on the surface of the control rod 305, it is convenient for material A, material B and material C to flow back from the discharge pipe to the return pipe and the material tank. The circulation of the raw materials can ensure the timely response and operation of the equipment, prevent liquid accumulation, and ensure the stable operation of the equipment. At this time, the raw materials of the mixing head 3 enter the nozzle of the spray barrel through the feed hole of the mixing head 3 and then enter the return groove of the control rod 305.

[0115] In a specific embodiment of the present invention, the A material tank 101, the B material tank 102 and the C material tank 201 are all connected to a temperature control device 5, and the temperature control device 5 includes a water-type raw material temperature controller 501. The water-type raw material temperature controller 501 is connected to a jacketed heat exchanger arranged outside the A material tank 101 and the B material tank 102 through a water pipeline, and a heat insulation layer is provided on the outside of the jacketed heat exchanger.

[0116] The temperature of material A and material B can be indirectly controlled by controlling the water temperature in the jacketed heat exchanger. During specific production, a water storage tank and an electric heater are installed inside the water-type raw material temperature controller 501. The control accuracy of the water-type raw material temperature controller 501 is ±1°C. The water-type raw material temperature controller 501 is installed on the near side of the A material tank 101, the B material tank 102 and the C material tank 201 respectively. The water-type raw material temperature controller 501 continuously passes circulating hot water into the jacketed heat exchangers of the A material tank 101, the B material tank 102 and the C material tank 201. The efficient circulating water temperature control system can ensure that the temperature control of the material tank is accurately controlled to ±1°C.

[0117] In a specific embodiment of the present invention, the A material tank 101 and the B material tank 102 are both connected to a raw material stirrer 103, and the raw material stirrer 103 can stir continuously or indirectly. The uniformity and temperature stability of the A material and the B material can be maintained by stirring.

[0118] In a specific embodiment of the present invention, the A material tank 101 and the B material tank 102 are both connected to a low-pressure feeding pump 104, and the two low-pressure feeding pumps 104 are respectively connected to different high-pressure metering pumps through pipelines. In specific design, the low-pressure feeding pump 104 can be set below the A material tank 101 and the B material tank 102 to extract the raw materials from the material tank and transport them to the side of the high-pressure metering pump.

[0119] In a specific embodiment of the present invention, the high-pressure metering pump is arranged in the heat preservation box 105, and a volume flow meter is also arranged in the heat preservation box 105, and the volume flow meter is connected to the high-pressure metering pump through a pipeline. The volume flow meter can be used to measure the delivery rate of the high-pressure metering pump.

[0120] In a specific embodiment of the present invention, the A material tank 101 and the B material tank 102 are both connected to a vacuum generator 106 .

[0121] In the specific design, the vacuum generator 106 can be respectively set on the A material tank 101 and the B material tank 102 to continuously extract air from the material tanks to ensure that the vacuum degree in the raw material tank can be less than 0.2 bar (that is, the air pressure can be less than 0.8 bar), and ensure that the air in the raw material is discharged as much as possible. Figure 6 As shown, vacuum generators 106 are installed on material tank A 101 and material tank B 102, respectively, which has the following beneficial effects: ① It can solve the problem of bubbles and poor appearance of the polyurethane (PUR) layer on the surface of the product; ② When new materials are added to material tank A 101 and material tank B 102, the bubbles generated in the material tanks can be effectively extracted in time, thereby ensuring product quality; ③ Integrating the vacuum generators 106 on material tank A 101 and material tank B 102, respectively, can effectively reduce the investment in plant space and auxiliary equipment.

[0122] In a specific embodiment of the present invention, the mixing head 3 is connected to a hydraulic power station 306, and the cleaning rod 304 and the control rod 305 are telescopically moved by the hydraulic power provided by the hydraulic power station 306. The main function of the hydraulic power station 306 is to control the opening and closing of the mixing head 3.

[0123] In a specific embodiment of the present invention, the A material tank 101, the B material tank 102, and the hydraulic power station 306 are all installed on a bracket 601, and the bracket 601 is also provided with an AB material electric control cabinet 6011 and an AB material automatic replenishing device 6012.

[0124] AB material electric control cabinet 6011 is used to control the main process parameters such as flow rate, temperature, ratio, opening time of mixing head and injection speed of A material and B material in the equipment. Figure 3 As shown, the heat preservation box 105 is arranged on the bracket 2 602. The integration of the equipment on the bracket 1 601 can greatly reduce the site space required for the equipment. The heat preservation box 105 is independently arranged on the bracket 2 602, which can reduce the interference of the vibration of the equipment on the bracket 1 601 on the high-pressure metering pump and the volume flow meter in the heat preservation box 105, thereby effectively ensuring the processing accuracy.

[0125] In a specific embodiment of the present invention, the color paste conveying device 2 is arranged on a color paste station bracket.

[0126] The color paste conveying device 2 specifically includes a C material tank 201, a water-type raw material temperature controller connected to the C material tank, a pumping piston pump, a volume flow meter, and a C material electric control cabinet. The present invention also includes a centralized control system 9, which is used to control each group of devices in the present invention (including the AB material electric control cabinet and the C material electric control cabinet).

[0127] During specific use, material C is set according to the physical property requirements of the customer's materials and the mixing ratio of 1% to 8% of the total volume of material A, material B and material C. Material C flows out from material tank C 201 through a pumping piston pump (the pumping piston pump can make the maximum pressure of material C reach 220 bar, which is a high-pressure pump) according to a preset flow rate, pressure (such as 150 bar) and ratio from a discharge pipe C2011 with a heating function; material A and material B respectively flow from corresponding material tanks through a low-pressure feeding pump 104 to a high-pressure metering pump, and flow out from discharge pipes A1011 and B1021 with a heating function according to a preset flow rate, pressure (such as 150 bar) and ratio; material A, material B and material C are mixed together in a turbulent manner in the mixing head 3, and after mixing, the reaction molding coating enters the molding mold 4 from the pipeline, and forms a PUR polyurethane / PUA polyurea coating layer with a color effect on the surface of the substrate in the molding mold 4.

[0128] In a specific embodiment of the present invention, the environmentally friendly in-mold coating processing equipment for plastic products further includes an injection molding device 7, and the injection molding device 7 is provided with an automatic plastic feeding device 701, a hopper and a raw material drying system.

[0129] In a specific embodiment of the present invention, the molding die 4 includes a slide die plate and a fixed die plate;

[0130] The slide template is provided with two half-molds, half-mold 1 and half-mold 2, and the fixed template is provided with half-mold 3. The half-mold 1 and the half-mold 2 can be switched to dock with the half-mold 3 by translation and sliding;

[0131] The half mold 3 is connected to the discharge end of the injection molding device 7 and the discharge end of the mixing head 3;

[0132] The first half mold and the third half mold are molded together to form an injection molding substrate cavity;

[0133] The second half mold and the third half mold are molded together to form a reaction molding coating cavity.

[0134] In a specific embodiment of the present invention, the molding die 4 includes a movable die plate and a front die plate;

[0135] like Fig.14As shown, the movable platen is provided with a rotating mechanism that can rotate 360° along the vertical axis, and the movable platen is also provided with a horizontal moving mechanism, and the movable platen includes a first half mold 401 and a second half mold 402;

[0136] The front template is provided with a horizontal moving mechanism, and the front template comprises a third half-mold 403 and a fourth half-mold 404;

[0137] The third half mold 403 is connected to the discharge end of the injection molding device 7, and the first half mold 401 and the second half mold 402 can be molded together with the third half mold 403 to form an injection molding substrate cavity;

[0138] The fourth half mold 404 is connected to the discharge end of the mixing head 3 , and the first half mold 401 and the second half mold 402 can be molded together with the fourth half mold 404 to form a reaction molding coating cavity.

[0139] Taking PUR polyurethane coating and plastic substrate as an example, in the specific design, the first half mold 401 and the second half mold 402 of the movable mold are provided with ejector pins and exhaust mechanisms, and the fourth half mold 404 of the fixed mold is provided with a PUR polyurethane feed channel. Preferably, the temperature control unit 1 controls the first half mold 401 and the second half mold 402 of the movable mold and the third half mold 403 of the front mold. According to different specifications and types of raw materials, the mold temperatures of the first half mold 401, the second half mold 402 and the third half mold 403 are 80°C to 110°C. Preferably, the mold temperature control unit 2 controls the fourth half mold 404 of the front mold, and the mold temperature of the fourth half mold 404 is 90°C to 130°C. Controlling the mold temperature of the moving mold plate and the front mold plate can further reduce the adverse effects of mold temperature on PUR polyurethane and substrate materials. Setting the mold temperature of the first half mold 401 and the second half mold 402 of the moving mold plate and the third half mold 403 of the front mold plate in the range of 80℃~110℃ and the mold temperature of the fourth half mold 404 of the front mold plate in the range of 90℃~130℃ can ensure that the PUR material reacts and solidifies steadily after entering the mold cavity, without affecting product quality and subsequent processes. When the mold temperature of the fourth half mold 404 is lower than 90℃ and the mold temperature of the first half mold 401 and the second half mold 402 and the third half mold 403 of the front mold plate is lower than 80℃, the PU layer of the product will have the following Figure 7 , 8 When the temperature of the fourth half mold 404 is higher than 130°C and the temperature of the first half mold 401, the second half mold 402 and the front mold third half mold 403 is higher than 110°C, the PU layer of the product will have the following problems: Fig. 9 , 10 The difficulty in glue feeding shown in the figure leads to the undesirable phenomenon of material shortage and overall deformation of the product.

[0140] In specific use, taking PUR polyurethane coating and plastic substrate as an example, after the two half molds of the movable template and the two half molds of the front template are molded together, an injection molding substrate cavity and a reaction molding coating cavity (PUR polyurethane cavity) are respectively formed. After the molding mold 4 is molded together, injection is first started in the injection molding substrate cavity formed by the first half mold 401 of the movable template and the third half mold 403 of the front template. When the substrate is injected and pressure-holding filling is completed and cooled, the mold is opened, and the movable template is rotated 180° to send the first half mold with the injection substrate attached to the fourth half mold 404. The molding mold 4 is molded again, and plastic is injected into the injection molding substrate cavity formed by the second half mold 402 of the movable template and the third half mold 403 of the front template, and in the reaction molding coating cavity (in the PUR polyurethane cavity) formed by the first half mold 401 and the fourth half mold 404 of the front template, reaction injection molding (Reaction Injection The reaction molding coating (PUR polyurethane) is injected and poured by the reaction molding coating (RIM) equipment. At this time, the injection-molded substrate in the reaction molding coating cavity (PUR polyurethane cavity) can form an in-mold painted coating product with high surface quality. There is no need to place the injection-molded substrate product in another set of equipment for surface spraying or painting. The present invention can realize the painting process in the mold, thereby effectively improving the production efficiency.

[0141] In a specific embodiment of the present invention, an automatic picking device 801 for taking out the workpiece from the forming mold 4 is provided on one side of the forming mold 4, and an automatic trimming device 802 for trimming the workpiece is provided on one side of the automatic picking device 801, and the automatic picking device 801 and the automatic trimming device 802 are both arranged in the automated isolation guardrail 8.

[0142] In a specific embodiment of the present invention, the number of the C material tanks 201 is more than two.

[0143] The number of C material tanks 201 is set to more than two to take into account the color switching. The present invention can quickly complete the multiple color switching within 5 minutes. Figure 4 As shown, the A material and B material components in the A material tank 101 and the B material tank 102 are kept clean, the color paste is added to the paste conveying device 2, and the C material tank 201 of different colors is switched through the replacement unit of the paste conveying device 2. The switching of different colors can be completed in about 5 minutes.

[0144] In a specific embodiment of the present invention, the environmentally friendly in-mold coating processing equipment for plastic products is controlled by input and output logic of digital signals, and the control logic of the digital signals includes one or more of the following:

[0145] D1. When the environmentally friendly plastic product in-mold coating processing equipment fails, a "DO mechanical failure" signal is output;

[0146] D2. When the mold half 1 and the mold half 3 are combined to form a mold cavity for the injection molded substrate, a "DO cleaning rod advances" signal is output, and the output is disconnected before the "DO ready to foam" signal is output; after the cleaning rod 304 advances to the right position, the system outputs a "DI cleaning rod advances to the right position" signal, and the "DI cleaning rod advances to the right position" signal is effective at a high level;

[0147] The purpose of executing the "cleaning rod forward signal" is to prevent the plastic substrate from entering the injection gun head of the polyurethane equipment when the plastic substrate is injected. In the turntable mode (the molding mold 4 includes a movable mold plate and a front mold plate), there is no need to output the "DO cleaning rod forward" signal, but in the slide mode (the molding mold 4 includes a slide mold plate and a fixed mold plate), the "DO cleaning rod forward signal" needs to be output when the injection molded substrate cavity is formed after the half mold one and the half mold three are molded together, and the output is disconnected before the "DO ready to foam" signal is output. This is because the mold structure is different. In the turntable mode, the mold, the injection of the substrate and the injection of polyurethane are connected to different half molds respectively (the third half mold 403 is connected to the discharge end of the injection molding device 7, and the fourth half mold 404 is connected to the discharge end of the in-mold coating device 2), and there is no need to consider the problem of the substrate entering the injection gun head of the polyurethane equipment. The slide mode is different. In the slide mode, the substrate and polyurethane are injected using the same cavity surface (the half mold 3 is connected to the discharge end of the injection device 7 and the discharge end of the in-mold coating device 2). Therefore, when the substrate is injected, it is necessary to prevent the plastic substrate from entering the injection gun head of the polyurethane device. Therefore, the cleaning rod 304 should be kept in the forward position until the polyurethane injection preparation signal is output. In the turntable mode, the "DO cleaning rod forward" signal skips the control process and directly enters the next step.

[0148] High level is valid if the signal is a high charge to activate the alarm, 0 is low level, 1 is high level, 0~14V is low level, 15~28V is high level. In the slide mode, the IMM (Injection Molding Machine) checks the "DI cleaning rod forward in place" signal before injection. If the "DI cleaning rod forward in place" signal is lost, the plastic injection action is prohibited, and the alarm "cleaning rod is not in the forward position" is prompted. At this time, there is no need to jump out of the automatic mode, just wait in place, and continue to inject plastic after the "DI cleaning rod forward in place" signal is input into the system. Monitoring the position of the cleaning rod 304 in the slide mode is for quality, safety and equipment stability considerations, because in the slide mode, the substrate injection and polyurethane injection share a cavity surface (half mold three) on the fixed mold plate, also known as the (static mold) side, so when the substrate is injected, it is necessary to ensure that the cleaning rod 304 is in the forward position to prevent the substrate from being injected into the polyurethane equipment gun head.

[0149] D3. When the environmentally friendly plastic product in-mold coating processing equipment is in semi-automatic / fully automatic mode, a "DO automatic operation" signal is output;

[0150] The difference between the semi-automatic and fully automatic environmentally friendly plastic product in-mold coating processing equipment is that in the semi-automatic mode, after a complete cycle is completed, manual confirmation and pressing the start button are required to execute the next cycle, while in the fully automatic mode, after a complete cycle is completed, the next cycle can be automatically executed without manual confirmation.

[0151] D4. When the reaction molding coating cavity is formed after mold closing, the "DO ready to foam" signal is triggered, and the "DO ready to foam" signal is disconnected before the "DO start foaming" signal is output;

[0152] During specific design, the "DO ready to foam" signal can set the output delay time. The task of establishing high pressure of polyurethane is performed between the "DO ready to foam" signal and the "DO start foaming" signal, that is, polyurethane material A and material B establish high pressure (enter the high pressure metering pump) to prepare for injection into the molding cavity.

[0153] D5. When the system receives the "DI ready for foaming" signal, it outputs the "DO start foaming" signal; when the system receives the "DI foaming completed" signal, it disconnects the "DO start foaming" signal output and enters the foaming cooling timing, the "DI foaming completed" signal is valid at a high level; the "DI ready for foaming" signal is valid at a high level, and the "DO start foaming" signal output is prohibited without a high-level signal; the "DI foaming completed" signal is valid at a high level; the purpose of the foaming cooling timing is to accurately measure the polyurethane curing and cooling time to ensure product quality. When the conveying speed of the A and B materials of the polyurethane equipment reaches the set injection speed, and runs at this speed for more than 2s without fluctuation, the system will determine that the polyurethane injection conditions are met and output the "DI ready for foaming" signal.

[0154] D6. When the foaming machine is foaming, the system outputs a "DI is foaming" signal. The "DI is foaming" signal is effective at a high level, and no alarm is output;

[0155] D7. Trigger the "DO cleaning rod blowing" signal through the "DI foaming completed" signal;

[0156] During the specific design, the "DO Blow Cleaning Rod" signal can set the delay time and output time. After the "DO Blow Cleaning Rod" signal is sent, a blow valve will be activated at the gun head of the polyurethane foaming equipment to remove the residual polyurethane material outside the cleaning rod 304 to prevent residual defects during the next injection cycle. More specifically, the system does not need the "DO Cleaning Rod Retreat" signal. When the polyurethane is injected and foamed, the cleaning rod 304 will automatically perform a retreat action. When the foaming is completed, the cleaning rod 304 will automatically perform a forward action. This program can be set through the built-in polyurethane equipment. The delay time is set to more accurately control the reasonable blowing time, and the output time is to accurately control the blowing time.

[0157] D8. When the foaming machine fails, the system outputs a "DI foaming machine failure" signal. The "DI foaming machine failure" signal is effective at a high level. When the "DI foaming machine failure" signal is input into the system, the system alarms "foaming machine failure" and prohibits the system from entering the automatic mode with "foaming action". If in the automatic mode, it jumps to the manual mode after the cycle ends;

[0158] The foaming machine specifically includes an in-mold coating device 1, a color paste delivery device 2, a mixing head 3, and other equipment related to polyurethane foaming. The automatic mode here includes the semi-automatic mode and the fully automatic mode mentioned above. The manual mode is the third mode of the environmentally friendly in-mold coating processing equipment for plastic products. In this mode, the system does not send a control signal to the polyurethane equipment.

[0159] D9. When the downstream equipment of the injection molding machine detects unqualified products, a "DI product unqualified" signal is input to the system, and the high level of the "DI product unqualified" signal is valid.

[0160] When the system receives the "DI product unqualified" signal, the IMM injection molding machine system outputs the "DI product unqualified" signal (waste signal) to the automation equipment (including the automatic pick-up device 801, the automatic trimming device 802, etc.). In specific use, the polyurethane reaction molding equipment control software can accurately measure whether the injected polyurethane weight, time, and speed are consistent with the set requirements. If the measured actual injected polyurethane weight or time or speed deviates from the actual set value by more than 1%, the polyurethane reaction molding equipment will output a high-level product unqualified signal to the IMM injection molding machine system. After receiving the signal, the IMM injection molding machine system will automatically output the product unqualified signal to the automation equipment. Fig.13 The figure shows the logic diagram of the system in the present invention for processing unqualified products.

[0161] Preferably, Fig.11 , 12 This is an overview of the I / O signal block diagram in turntable mode and slider mode.

[0162] The above control logic can be flexibly matched with different types of injection molding equipment and mold turning equipment according to customer production needs to meet the production of products with different specifications. The "system" mentioned in the above control logic can be integrated into Figure 2 In the centralized control system 9 shown.

[0163] An environmentally friendly in-mold coating process for plastic products, using environmentally friendly in-mold coating processing equipment for plastic products, such as Fig.14 As shown, the following steps are included:

[0164] S01. Mold closing, at which time the first half mold 401 and the third half mold 403 are molded together to form an injection molding substrate cavity for the first workpiece, and the injection molding device 7 injects the first workpiece substrate into the injection molding substrate cavity;

[0165] S02. Maintain the mold, and perform pressure holding and cooling of the first workpiece substrate;

[0166] S03. Open the mold, attach the first workpiece substrate to the first half mold 401, and close the mold after the movable mold plate rotates 180 degrees. At this time, the first half mold 401 and the fourth half mold 404 are closed to form a reaction molding coating cavity with the first workpiece substrate built in, and the second half mold 402 and the third half mold 403 are closed to form an injection molding substrate cavity for the second workpiece;

[0167] S04. Keep the mold closed, while the mixing head 3 injects the reaction molding coating onto the surface of the first workpiece substrate, the injection molding device 7 simultaneously injects the second workpiece substrate;

[0168] S05. Keep the mold closed, while the reaction molding coating is reacting and molding on the surface of the first workpiece substrate, the second workpiece substrate is simultaneously pressurized and cooled;

[0169] S06. Open the mold, attach the first workpiece that has been painted to the first half mold 401, attach the second workpiece substrate to the second half mold 402, and remove the first workpiece that has been painted from the first half mold 401 by the automatic removal device 801;

[0170] S07. After the movable mold plate rotates 180°, the second mold half 402 and the fourth mold half 404 are molded together to form a reaction molding coating cavity with a second workpiece substrate built in, and the first mold half 401 and the third mold half 403 are molded together to form an injection molding substrate cavity for the third workpiece;

[0171] S08. Keep the mold closed, while the mixing head 3 injects the reaction molding coating onto the surface of the second workpiece substrate, the injection molding device 7 simultaneously injects the third workpiece substrate;

[0172] S09. The mold is kept closed, and while the reaction molding coating is reacting and molding on the surface of the second workpiece substrate, the pressure holding and cooling of the third workpiece substrate are carried out simultaneously;

[0173] S010 . Open the mold, attach the painted second workpiece to the second half mold 402 , attach the third workpiece substrate to the first half mold 401 , and remove the painted second workpiece from the second half mold 402 by the automatic removing device 801 .

[0174] Repeating steps S07-S010 can achieve continuous and efficient production of environmentally friendly in-mold coating of plastic products.

[0175] S01~S010 is a process in which the injection molding machine molds the substrate once and then completes one-step coating in the mold. In this process, the substrate does not need to be demolded first and then transported to the painting station by transfer to complete the painting. It can solve the problems of product deformation and difficulty in secondary positioning of the painting station. The specific implementation can be summarized as follows: the molding mold 4 is closed, the thermoplastic substrate is first injected, and after pressure holding filling and cooling, the molding mold 4 is opened, and the turntable is rotated 180° toward the operating side to move the injected substrate to another cavity corresponding to the casting of PUR polyurethane. The molding mold 4 is closed again. At this time, the system sends a coating start signal, and the coating equipment opens the mixing head to start injecting PUR polyurethane material into the surface of the substrate (at the same time, the injection molding machine injects the substrate for the next cycle). After the coating equipment finishes casting, the part in the mold completes reaction and curing, and the molding mold 4 is opened to eject the part, and the automatic removal device 801 (mechanical gripper) takes out the part.

[0176] In a specific embodiment of the present invention, the injection molding substrate material of the injection molding device includes one or more of polypropylene, PC, ABS, PC+ABS, PA66 and carbon fiber.

[0177] In a specific embodiment of the present invention, when the reaction molding coating is polyurethane, and the molding mold 4 includes the movable mold plate and the front mold plate, the melting temperature of the barrel of the injection molding device 7 is 200°C to 320°C, the mold temperatures of the first half mold 401, the second half mold 402 and the third half mold 403 are 80°C to 110°C, the mold temperature of the fourth half mold 404 is 90°C to 130°C, the temperature of the polyurethane material entering the reaction molding coating cavity is 60°C to 90°C, the working pressure of the polyurethane material entering the reaction molding coating cavity is 11MPa to 21MPa, and the curing time of the polyurethane material in the reaction molding coating cavity is 20s to 200s.

[0178] In a specific embodiment of the present invention, the injection molding substrate material is polypropylene, the melting temperature of the barrel of the injection molding device 7 is 170° C. to 250° C., the injection molding substrate is a polypropylene substrate, and the in-mold coating process of the polypropylene substrate includes the following steps:

[0179] S11. The injection molding device 7 injects a polypropylene substrate into the injection molding substrate cavity;

[0180] S12. The completed injection-molded polypropylene substrate is sent to the PLASMA surface treatment equipment model SPA2800 for plasma treatment by rotating the turntable;

[0181] S13. Injection molding of polyurethane material on the surface of the plasma-treated polypropylene substrate;

[0182] S14. Open the mold and take out the finished product with polypropylene and polyurethane materials bonded together.

[0183] In a specific embodiment of the present invention, the technical parameters of the PLASMA surface treatment equipment are: voltage 190V-250V, frequency 40HZ-60HZ, current 0.25A-0.35A, air pressure 0.4bar-0.8bar, treatment width 20-90mm. Preferably, voltage 220V, frequency 50HZ, current 0.31A, air pressure 0.6bar, treatment width 75mm.

[0184] In a specific embodiment of the present invention, the technical parameters of the PLASMA surface treatment equipment are that the height of the plasma from the substrate surface is 8 mm to 15 mm, the plasma movement speed is 50 mm / s to 150 mm / s, and the plasma temperature is 70° C. to 100° C. Preferably, the height of the plasma from the substrate surface is 10 mm, the plasma movement speed is 100 mm / s, and the plasma temperature is 90° C.

[0185] In a specific embodiment of the present invention, the environmentally friendly in-mold coating processing equipment for plastic products in the present invention can select a variety of mold microstructure production according to customer production needs, such as: floral patterns, mirror surfaces, genuine leather, frosted textures, diamond-cut surfaces, engraved patterns and other fine textures. In specific implementation, polyurethane is a "smart" material that can be soft or hard, wear-resistant, scratch-resistant, self-repairing, and has the characteristics of free color matching and bright colors. The unique advantages of polyurethane materials such as perfect reproducibility enable the mold surface texture to be nearly 99% completely replicated. In order to better present the effect and meet actual functional requirements, the mold texture can be made on the substrate surface or on the PUR polyurethane surface. The specific texture effects include Fig.15 The following effects are shown in:

[0186] A. Leather effect: The leather effect texture can be made on the surface of the substrate or on the PUR polyurethane surface to achieve a perfect replica effect;

[0187] B. LOGO effect: The LOGO effect texture can be made on the surface of the substrate or on the surface of PUR polyurethane to achieve a perfect replica effect;

[0188] C. Smart diaphragm effect: Smart diaphragms can be embedded using IMD, IML and IMR processes to achieve smart surface effects;

[0189] D. Multiple types of texture effects: woven texture, diagonal texture, wavy texture and Fig.15 Other effect textures shown in D can be made on the surface of the substrate or on the surface of PUR polyurethane to achieve a perfect replica effect.

[0190] E. Diamond cutting effect: Diamond cutting effect and Fig.15 Other effect textures shown in E can be made on the surface of the substrate or on the surface of PUR polyurethane to achieve a perfect replica effect.

[0191] F. Wood grain texture effect: The wood grain effect and Fig.15 Other effect textures shown in F use IMD, IML and IMR embedding processes to achieve the advanced sensory effect of wood grain; the texture in the wood grain texture effect is attached to the surface of the substrate, and the texture surface layer is PUR polyurethane surface layer.

[0192] In a specific embodiment of the present invention, the environmentally friendly in-mold coating processing equipment for plastic products of the present invention can be flexibly matched with the following different types of injection molding machines according to the production requirements of customers:

[0193] like Fig.16 As shown, the environmentally friendly in-mold coating processing equipment for plastic products can be matched with electric injection molding machines with a clamping force of 50 tons to 450 tons or even larger tonnage, so as to meet the in-mold coating process requirements of 30g to 450g precision small-weight products.

[0194] like Fig.17 As shown in the figure, the environmentally friendly in-mold coating processing equipment for plastic products can be matched with hydraulic injection molding machines with a clamping force of 450 tons to 5500 tons or even larger, meeting the in-mold coating process requirements of products weighing 500g to 3000g or even larger.

[0195] like Fig.18 As shown, the environmentally friendly in-mold coating processing equipment for plastic products can be matched with a counter-shot or multi-shot multi-component injection molding machine with a clamping force of 450 tons to 5500 tons or even larger, meeting the in-mold coating process requirements of products weighing 500g to 4000g or even larger.

[0196] like Fig.19 As shown, the environmentally friendly in-mold coating processing equipment for plastic products can be matched with mold turning mold frame equipment with a clamping force of 50 tons to 1,300 tons or even larger tonnage to meet the in-mold coating process requirements of products in different application scenarios.

[0197] In summary, the environmentally friendly in-mold coating processing equipment for plastic products of the present invention has a high degree of equipment integration, can reduce processing steps, is stable, and is flexible and convenient to operate. It can obtain high-quality product surfaces with a variety of color effects, and can be flexibly matched with different types of injection molding machines and mold frame equipment according to customer production needs, and can meet customer production needs in different application scenarios.

[0198] It should be noted that the terms used in the present invention are only for describing specific embodiments, rather than limiting the scope of the present invention. As shown in the present specification, unless the context clearly indicates an exception, the words "one", "a", "a kind of" and / or "the" do not specifically refer to the singular, but may also include the plural. The terms "include", "comprise" or any other variant thereof are intended to cover non-exclusive inclusion, so that the process, method or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method or device. In the absence of more restrictions, the elements defined by the sentence "include one..." do not exclude the presence of other identical elements in the process, method or device including the elements.

[0199] It should also be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. Unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", etc. should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0200] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the technical solutions of the embodiments of the present invention.

[0201] In addition, it should be noted that the shapes and names of the parts and components of the specific embodiments described in this specification may be different. Any equivalent or simple changes made based on the structure, features and principles described in the patent concept of the present invention are included in the protection scope of the patent of the present invention. The technicians in the technical field of the present invention can make various modifications or supplements to the specific embodiments described or replace them in a similar manner, as long as they do not deviate from the structure of the present invention or exceed the scope defined by the claims, they should all fall within the protection scope of the present invention.

Claims

1. An environmentally friendly in-mold coating processing equipment for plastic products, comprising an in-mold coating device (1), a color paste conveying device (2), a mixing head (3) and a molding mold (4), characterized in that: The in-mold coating device (1) comprises an A material tank (101) for supplying A material and a B material tank (102) for supplying B material, and the color paste conveying device (2) comprises a C material tank (201) for supplying C material, the A material, the B material and the C material are mixed inside the mixing head (3) to form a reactive molding coating, and the discharge end of the mixing head (3) is connected to the coating feed end of the molding mold (4); The A material tank (101) is connected to the feed port A (301) of the mixing head (3) via a discharge pipe A (1011) and a return pipe A (1012); The B material tank (102) is connected to the feed port B (302) of the mixing head (3) via a discharge pipe B (1021) and a return pipe B (1022); The C material tank (201) is connected to the feed port C (303) of the mixing head (3) via a discharge pipe C (2011) and a return pipe C (2012); The mixing head (3) is provided with a cleaning rod (304) and a control rod (305), wherein the cleaning rod (304) is used to clean the paint residue in the mixing head (3) and to block the discharge port of the mixing head (3), and the control rod (305) is used to block or open the feed port A (301), the feed port B (302) and the feed port C (303); When the control rod (305) is in the closed position: the A material can circulate in the A material tank (101), the discharge pipe A (1011) and the return pipe A (1012); the B material can circulate in the B material tank (102), the discharge pipe B (1021) and the return pipe B (1022); and the C material can circulate in the C material tank (201), the discharge pipe C (2011) and the return pipe C (2012).

2. The environmentally friendly in-mold coating processing equipment for plastic products according to claim 1 is characterized in that: The A material tank (101), the B material tank (102) and the C material tank (201) are all connected to a temperature control device (5), and the temperature control device (5) comprises a water-type raw material temperature controller (501). The water-type raw material temperature controller (501) is connected to a jacketed heat exchanger arranged outside the A material tank (101) and the B material tank (102) through a water pipeline, and a heat insulation layer is arranged outside the jacketed heat exchanger.

3. The environmentally friendly in-mold coating processing equipment for plastic products according to claim 2 is characterized in that: The A material tank (101) and the B material tank (102) are both connected to a raw material stirrer (103), and the raw material stirrer (103) can stir continuously or indirectly.

4. The environmentally friendly in-mold coating processing equipment for plastic products according to claim 3 is characterized in that: The A material tank (101) and the B material tank (102) are both connected to a low-pressure feeding pump (104), and the two low-pressure feeding pumps (104) are respectively connected to different high-pressure metering pumps through pipelines.

5. The environmentally friendly in-mold coating processing equipment for plastic products according to claim 4 is characterized in that: The high-pressure metering pump is arranged in a heat-insulating box (105), and a volume flow meter is also arranged in the heat-insulating box (105), and the volume flow meter is connected to the high-pressure metering pump through a pipeline.

6. The environmentally friendly in-mold coating processing equipment for plastic products according to claim 5 is characterized in that: The A material tank (101) and the B material tank (102) are both connected to a vacuum generator (106).

7. The environmentally friendly in-mold coating processing equipment for plastic products according to claim 6 is characterized in that: The mixing head (3) is connected to a hydraulic power station (306), and the cleaning rod (304) and the control rod (305) are telescopically moved by the hydraulic power provided by the hydraulic power station (306).

8. The environmentally friendly in-mold coating processing equipment for plastic products according to claim 7 is characterized in that: The A material tank (101), the B material tank (102), and the hydraulic power station (306) are all installed on bracket one (601), and the bracket one (601) is also provided with an AB material electric control cabinet (6011) and an AB material automatic feeding device (6012).

9. The environmentally friendly in-mold coating processing equipment for plastic products according to claim 8, characterized in that: The color paste conveying device (2) is arranged on the color paste station bracket.

10. The environmentally friendly in-mold coating processing equipment for plastic products according to claim 9, characterized in that: The environmentally friendly in-mold coating processing equipment for plastic products also includes an injection molding device (7), and the injection molding device (7) is provided with an automatic plastic feeding device (701), a hopper and a raw material drying system.

11. The environmentally friendly in-mold coating processing equipment for plastic products according to claim 10, characterized in that: The forming mold (4) comprises a slide mold plate and a fixed mold plate; The slide template is provided with two half-molds, half-mold 1 and half-mold 2, and the fixed template is provided with half-mold 3. The half-mold 1 and the half-mold 2 can be switched to dock with the half-mold 3 by translation and sliding; The third half mold is connected to the discharge end of the injection molding device (7) and the discharge end of the mixing head (3); The first half mold and the third half mold are molded together to form an injection molding substrate cavity; The second half mold and the third half mold are molded together to form a reaction molding coating cavity.

12. The environmentally friendly in-mold coating processing equipment for plastic products according to claim 10, characterized in that: The forming mold (4) comprises a movable mold plate and a front mold plate; The movable platen is provided with a rotating mechanism capable of rotating 360° along a vertical axis, and the movable platen is also provided with a horizontal moving mechanism, and the movable platen comprises a first half mold (401) and a second half mold (402); The front template is provided with a horizontal moving mechanism, and the front template comprises a third half-mold (403) and a fourth half-mold (404); The third half mold (403) is connected to the discharge end of the injection molding device (7), and the first half mold (401) and the second half mold (402) can be molded together with the third half mold (403) to form an injection molding substrate cavity; The fourth half mold (404) is connected to the discharge end of the mixing head (3), and the first half mold (401) and the second half mold (402) can be molded together with the fourth half mold (404) to form a reaction molding coating cavity.

13. The environmentally friendly in-mold coating processing equipment for plastic products according to claim 12, characterized in that: An automatic piece taking device (801) for taking a workpiece out of the forming mold (4) is provided on one side of the forming mold (4), and an automatic trimming device (802) for trimming the workpiece is provided on one side of the automatic piece taking device (801), and both the automatic piece taking device (801) and the automatic trimming device (802) are arranged in the automated isolation fence (8).

14. The environmentally friendly in-mold coating processing equipment for plastic products according to any one of claims 1 to 12, characterized in that: The number of the C material tanks (201) is more than two.

15. The environmentally friendly in-mold coating processing equipment for plastic products according to any one of claims 10 to 12, characterized in that: The environmentally friendly in-mold coating processing equipment for plastic products is controlled by the input and output logic of digital signals, and the control logic of the digital signals includes one or more of the following: D1. When the environmentally friendly plastic product in-mold coating processing equipment fails, a "DO mechanical failure" signal is output; D3. When the environmentally friendly plastic product in-mold coating processing equipment is in semi-automatic / fully automatic mode, the "DO automatic operation" signal is output; D4. When the reaction molding coating cavity is formed after mold closing, the "DO ready to foam" signal is triggered, and the "DO ready to foam" signal is disconnected before the "DO start foaming" signal is output; D5. When the system receives the "DI ready for foaming" signal, it outputs the "DO start foaming" signal; when the system receives the "DI foaming completed" signal, it disconnects the "DO start foaming" signal output and enters the foaming cooling timing, the "DI foaming completed" signal is valid at a high level; the "DI ready for foaming" signal is valid at a high level, and the "DO start foaming" signal output is prohibited if no high-level signal is received; the "DI foaming completed" signal is valid at a high level; D6. When the foaming machine is foaming, the system outputs a "DI is foaming" signal. The "DI is foaming" signal is effective at a high level, and no alarm is output; D7. Trigger the "DO cleaning rod blowing" signal through the "DI foaming completed" signal; D8. When the foaming machine fails, the system outputs a "DI foaming machine failure" signal. The "DI foaming machine failure" signal is valid at a high level. When the "DI foaming machine failure" signal is input into the system, the system alarms "foaming machine failure". The system is prohibited from entering the automatic mode with "foaming action". If in the automatic mode, it jumps to the manual mode after the cycle ends; D9. When the downstream equipment of the injection molding machine detects unqualified products, a "DI product unqualified" signal is input to the system, and the high level of the "DI product unqualified" signal is effective.

16. An environmentally friendly in-mold coating process for plastic products, using the environmentally friendly in-mold coating process equipment for plastic products as claimed in claim 13, characterized in that: The steps include: S01. Mold closing, at which time the first half mold (401) and the third half mold (403) are molded together to form an injection molding substrate cavity for the first workpiece, and the injection molding device (7) injects the first workpiece substrate into the injection molding substrate cavity; S02. Maintain the mold, and perform pressure holding and cooling of the first workpiece substrate; S03. Open the mold, attach the first workpiece substrate to the first half mold (401), and close the mold after the movable mold plate rotates 180 degrees. At this time, the first half mold (401) and the fourth half mold (404) are closed to form a reaction molding coating cavity with the first workpiece substrate built in, and the second half mold (402) and the third half mold (403) are closed to form an injection molding substrate cavity for the second workpiece; S04. While maintaining the mold, the mixing head (3) injects the reaction molding coating onto the surface of the first workpiece substrate, and the injection molding device (7) simultaneously injects the second workpiece substrate; S05. Keep the mold closed, while the reaction molding coating is reacting and molding on the surface of the first workpiece substrate, the second workpiece substrate is simultaneously pressurized and cooled; S06. Open the mold, attach the first workpiece that has been painted to the first half mold (401), attach the second workpiece substrate to the second half mold (402), and the automatic pick-up device (801) takes out the first workpiece that has been painted from the first half mold (401); S07. After the movable mold plate is rotated 180°, the mold is closed, and at this time, the second half mold (402) and the fourth half mold (404) are closed to form a reaction molding coating cavity with a second workpiece substrate built in, and the first half mold (401) and the third half mold (403) are closed to form an injection molding substrate cavity for the third workpiece; S08. While maintaining the mold, the mixing head (3) injects the reaction molding coating onto the surface of the second workpiece substrate, and the injection molding device (7) simultaneously injects the third workpiece substrate; S09. The mold is kept closed, and while the reaction molding coating is reacting and molding on the surface of the second workpiece substrate, the pressure holding and cooling of the third workpiece substrate are carried out simultaneously; S010. Open the mold, attach the second workpiece that has been painted to the second half mold (402), attach the third workpiece substrate to the first half mold (401), and the automatic pick-up device (801) takes out the second workpiece that has been painted from the second half mold (402).

17. The environmentally friendly in-mold coating process for plastic products according to claim 16, characterized in that: The injection molding substrate material of the injection molding device includes one or more of polypropylene, PC, ABS, PC+ABS, PA66 and carbon fiber.

18. The environmentally friendly in-mold coating process for plastic products according to claim 17, characterized in that: When the reaction molding coating is polyurethane and the molding mold (4) includes the movable mold plate and the front mold plate, the melting temperature of the barrel of the injection molding device (7) is 200°C to 320°C, the mold temperatures of the first half mold (401), the second half mold (402) and the third half mold (403) are 80°C to 110°C, the mold temperature of the fourth half mold (404) is 90°C to 130°C, the temperature of the polyurethane material entering the reaction molding coating cavity is 60°C to 90°C, the working pressure of the polyurethane material entering the reaction molding coating cavity is 11MPa to 21MPa, and the curing time of the polyurethane material in the reaction molding coating cavity is 20s to 200s.

19. The environmentally friendly in-mold coating process for plastic products according to claim 18, characterized in that: The injection molding substrate material is polypropylene, the melting temperature of the barrel of the injection molding device (7) is 170° C. to 250° C., the injection molding substrate is a polypropylene substrate, and the in-mold coating process of the polypropylene substrate comprises the following steps: S11. The injection molding device (7) injects a polypropylene substrate into the injection molding substrate cavity; S12. The completed injection-molded polypropylene substrate is sent to the PLASMA surface treatment equipment model SPA2800 for plasma treatment by rotating the turntable; S13. Injection molding of polyurethane material on the surface of the plasma-treated polypropylene substrate; S14. Open the mold and take out the finished product with polypropylene and polyurethane materials bonded together.

20. The environmentally friendly in-mold coating process for plastic products according to claim 19, characterized in that: The technical parameters of the PLASMA surface treatment equipment are: voltage 190V-250V, frequency 40HZ-60HZ, current 0.25A-0.35A, air pressure 0.4bar-0.8bar, and treatment width 20-90mm.

21. The environmentally friendly in-mold coating process for plastic products according to claim 20, characterized in that: The technical parameters of the PLASMA surface treatment equipment are as follows: the height of the plasma from the substrate surface is 8 mm to 15 mm, the plasma moving speed is 50 mm / s to 150 mm / s, and the plasma temperature is 70° C. to 100° C.

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