Plastic motor suspension assembly and integrated injection molding manufacturing method thereof

Abstract

The invention relates to a plastic motor suspension assembly and an integrated injection molding manufacturing method thereof, the plastic motor suspension assembly comprises a plastic support, a rubber body and a metal insert, and the plastic support comprises a first inner hole and a second inner hole; the rubber body is located in the first inner hole; the metal insert is positioned in the second inner hole; the rubber body and the metal insert serve as an inner framework and are placed in an injection mold to be integrally formed with the plastic support in an injection molding mode. Two flat and straight surfaces are symmetrically arranged in the first inner hole, two bumps are further arranged in the first inner hole, and the flat and straight surfaces and the bumps are arranged at intervals; the rubber body comprises a metal inner core and a rubber main spring, a boss corresponding to the straight face is arranged on the metal inner core, and a protruding part corresponding to the bulge is arranged on the metal inner core. According to the method, rapid and lossless internal detection is carried out through the X-ray scanning equipment, whether key parts such as the supporting legs are damaged due to injection molding pressure or not can be directly seen according to images, and data driving and precision of process adjustment are achieved.

Description

Technical Field

[0001] This application relates to the field of vehicle mount manufacturing technology, and in particular to a plastic motor mount assembly and its integrated injection molding method. Background Technology

[0002] Engine mounts are key components in a car's engine compartment, connecting the powertrain (engine, electric motor, transmission, etc.) to the vehicle body. Their main functions are to support and secure the powertrain, while also attenuating vibrations and noise generated during powertrain operation, thus improving the vehicle's NVH performance. With the rapid development of new energy vehicles, electric motors are increasingly widely used in automobiles, with common speeds reaching up to 15,000 rpm or even higher. High-frequency vibrations are easily transmitted to the vehicle body through engine mounts, transforming into high-frequency noise inside the vehicle. New energy vehicles also place increasingly higher demands on engine mount performance. Traditional engine mounts, often made of rubber and metal, suffer from problems such as numerous assembled parts, heavy weight, and high cost.

[0003] Existing suspension assemblies typically use metal brackets. Due to the high modulus and low damping characteristics of the material, these are prone to high-frequency sound radiation. Furthermore, the brackets offer limited constraint on the rubber body. The rubber body and metal inserts, after being coated with adhesive, are placed in an injection mold, and then injection molded to form a suspension assembly. However, because injection molding involves injecting molten plastic at high pressure from a nozzle into the mold, the plastic, under high pressure and speed, compresses the rubber body, causing deformation of the rubber spring. This leads to changes in the rubber body's stiffness and cracking of the rubber spring, resulting in failures. Therefore, it is necessary to cut the product open with a cutting machine to observe the compression and optimize the injection parameters. This method is time-consuming, and the product's dimensions change after cutting, requiring multiple rounds of trial production to adjust the process effectively.

[0004] Therefore, we propose a plastic motor suspension assembly and its integrated injection molding manufacturing method.

[0005] Application content To address the shortcomings of existing production technologies, the applicant provides a plastic motor suspension assembly and its integrated injection molding method. This method utilizes X-ray scanning equipment for rapid, non-destructive internal inspection, allowing direct visualization of whether critical components such as the support legs are damaged due to injection pressure. This enables data-driven and precise process adjustments.

[0006] The technical solution adopted in this application is as follows: A plastic motor mount assembly, comprising: A plastic bracket, including a first inner hole and a second inner hole; The rubber body is located in the first inner hole; A metal insert is located in the second inner hole; Among them, the rubber body and metal inserts serve as the inner skeleton and are placed in the injection mold to be integrally injection molded with the plastic support; Two straight surfaces are symmetrically arranged inside the first inner hole, and two bulges are also arranged inside the first inner hole, with the straight surfaces and bulges spaced apart. The rubber body includes a metal inner core and a rubber main spring. The metal inner core is provided with a boss corresponding to the flat surface and a raised part corresponding to the bulge.

[0007] Its further features are: The plastic bracket has a barrier around its second inner hole. The inner diameter of the barrier is larger than the diameter of the second inner hole, and the lower surface of the barrier is lower than the upper surface of the second inner hole.

[0008] The metal insert extends above the plastic bracket, and the plastic bracket has a full-circle surround on the extended portion.

[0009] The rubber main spring has multiple support legs arranged in the middle.

[0010] The metal insert has a through hole in the middle, a groove in the middle, and arc-shaped notches arranged around the outer edges of both ends.

[0011] The first inner hole and the second inner hole penetrate the plastic bracket in different directions.

[0012] The plastic bracket is made of nylon fiberglass.

[0013] The rubber main spring has an upper rubber flange and a lower rubber flange. The upper and lower rubber flanges are coated with adhesive and are bonded to the plastic bracket as a whole. The upper rubber flange is provided with a rubber boss.

[0014] The rubber main spring has stop blocks on the flat surface and bulge of the corresponding plastic bracket.

[0015] A method for integral injection molding of a plastic motor suspension assembly includes the following steps: The first step is to use 3D software to model the plastic support and the rubber body; The second step is to use simulation software to import the rubber material parameters of the rubber body, simulate the vulcanization and cooling process of the rubber body, and obtain the deformation model of the cooled rubber body. The third step is to design and process the sliding mechanism of the injection mold based on the deformation model of the rubber body. The fourth step is to place the rubber body and metal inserts as the inner skeleton into the injection mold, with the sliding mechanism supporting the hollow part of the rubber body. The fifth step involves injection molding, which produces the suspension assembly. The sixth step is to scan the injection-molded suspension assembly with an X-ray scanning device to obtain an image of the suspension assembly. The injection molding process is then adjusted based on the image, and injection molding is performed again after the adjustment. Step 7: Repeat step 6 until the rubber at the support leg of the rubber body in the image is no longer compressed, thus obtaining a qualified suspension assembly and completing the injection molding process.

[0016] The beneficial effects of this application are as follows: This application features a compact and rational structure, and is easy to operate. It uses simulation software to model the deformation of rubber after vulcanization and cooling, and then designs and processes the mold's sliding mechanism based on this model. This reduces the risk and cost of trial and error in physical testing. X-ray scanning equipment is introduced for rapid, non-destructive internal inspection, allowing direct visualization of whether critical components such as support legs are damaged by injection pressure, enabling data-driven and precise process adjustments. Through rapid iteration of "scan-judgment-adjustment-re-injection," a real-time process optimization closed loop is formed, enabling process adjustments without stopping the machine and significantly reducing the number of repeated mold repairs and trials in traditional development. The finalized injection molding process becomes the core guarantee for stable production of high-quality products, ensuring product consistency and reliability.

[0017] In addition, this application also has the following advantages: (1) The flat surfaces and bulges on the plastic bracket, and the bosses and raised parts on the metal inner core, precisely match to form a multi-level limiting mechanism. This not only limits excessive displacement and protects the rubber main spring, but also allows for active adjustment of NVH performance through optimized dimensions.

[0018] (2) The bulge is provided with a weight reduction hole or weight reduction cavity. The bulge is connected to the inner surface of the first inner hole by a circular arc, which can ensure strength and meet the process forming requirements.

[0019] (3) The plastic bracket is made of nylon fiberglass and has a porous arched structure. While ensuring high strength and rigidity, it achieves a significant reduction in weight, which directly helps to improve the driving range of electric vehicles.

[0020] (4) The rubber boss avoids hard contact with surrounding parts, thus preventing abnormal noise that may be caused by friction.

[0021] (5) Plastic fills the arc-shaped notches and grooves, and the metal insert and plastic bracket form a structural interlock. This ensures that the metal insert and plastic bracket will not loosen under long-term high load, and the connection reliability is far superior to that of methods that rely solely on adhesive force. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure of this application.

[0023] Figure 2 for Figure 1 Enlarged diagram of point A in the middle.

[0024] Figure 3 This is a schematic diagram of the plastic bracket of this application.

[0025] Figure 4 for Figure 3 The main view.

[0026] Figure 5 This is a schematic diagram of the rubber body in this application.

[0027] Figure 6 This is a top view of the rubber body of this application.

[0028] Figure 7 This is a schematic diagram of the metal core of this application.

[0029] Figure 8 This is a schematic diagram of the metal insert of this application.

[0030] The components include: 1. Plastic support; 2. Rubber body; 3. Metal inserts. 11. First inner hole; 12. Second inner hole; 13. Enclosure; 14. Enclosing part; 21. Metal inner core; 22. Rubber main spring; 31. Through hole; 32. Arc-shaped notch; 33. Groove; 111. Flat surface; 112. Bump; 211. Boss; 212. Raised portion; 221. Support leg; 222. Upper rubber flange; 223. Rubber boss; 224. Lower rubber flange; 225. Stop block. Detailed Implementation

[0031] The specific embodiments of this application are described below with reference to the accompanying drawings.

[0032] like Figures 1-8 As shown, a plastic motor suspension assembly includes a plastic bracket 1, a rubber body 2, and a metal insert 3.

[0033] The plastic bracket 1 includes a first inner hole 11 and a second inner hole 12, which extend through the plastic bracket 1 in different directions. It is suitable for complex and compact automotive motor compartment spaces and installation conditions, as well as usage scenarios with more severe loads.

[0034] In one embodiment, there is one first inner hole 11 and multiple second inner holes 12, with the multiple second inner holes 12 respectively located at both ends of the plastic bracket 1.

[0035] Specifically, the second inner hole 12 can be set to four, or it could be any other number.

[0036] In one embodiment, the plastic bracket 1 is made of nylon fiberglass and has a porous arched structure. This achieves significant weight reduction while maintaining high strength and rigidity, directly contributing to an increase in the driving range of electric vehicles.

[0037] In one embodiment, the first inner hole 11 of the plastic bracket 1 has a flat surface 111 and a bulge 112, which are spaced apart.

[0038] Specifically, there are two flat surfaces 111 and two bulges 112. The two flat surfaces 111 are symmetrically arranged, and the two bulges 112 are symmetrically arranged. The displacement of the metal core 21 of the rubber body 2 is limited by the flat surfaces 111 and the bulges 112, so as to ensure the fatigue performance of the rubber body 2.

[0039] The flat surface 111 and the bulge 112 on the plastic bracket 1 precisely match the protrusion 211 and the raised part 212 on the metal inner core 21, forming a multi-level limiting mechanism. This not only limits excessive displacement and protects the rubber main spring 22, but also allows for active adjustment of NVH performance through optimized dimensions.

[0040] In one embodiment, the bulge 112 is provided with a weight-reducing hole or a weight-reducing cavity inside, and the bulge 112 is connected to the inner surface of the first inner hole 11 by an arc, which can ensure strength and meet the process forming requirements.

[0041] The plastic bracket 1 has a barrier 13 outside the second inner hole 12. The inner diameter of the barrier 13 is larger than the diameter of the second inner hole 12, and the lower surface of the barrier 13 is lower than the upper surface of the second inner hole 12.

[0042] In one embodiment, the enclosure 13 is a fully enclosed or semi-enclosed structure along the second inner hole 12, and the enclosure 13 can improve the modal and dynamic stiffness of the suspended product and the mounting point.

[0043] The rubber body 2 is formed by vulcanizing a metal inner core 21 and a rubber main spring 22. The rubber main spring 22 has a continuous structure, which improves the vulcanization process and enhances the bonding strength with the plastic bracket 1. Multiple support legs 221 are arranged in the middle of the rubber main spring 22 to provide different stiffness in different directions. In one embodiment, four support legs 221 are provided, and the four support legs 221 are arranged in an X shape.

[0044] The metal inner core 21 has a through mounting hole, the direction of which is the same as that of the first inner hole 11. It is connected to the motor through the through mounting hole. The metal inner core 21 has a boss 211 and a raised part 212. The boss 211 corresponds to the flat surface 111 of the plastic bracket 1, and the raised part 212 corresponds to the bulge 112 of the plastic bracket 1. The NVH performance of the plastic motor mounting assembly can be optimized by adjusting the size.

[0045] The rubber main spring 22 has an upper rubber flange 222 and a lower rubber flange 224. The upper rubber flange 222 and the lower rubber flange 224 are coated with adhesive and are bonded to the plastic bracket 1 as a whole. The upper rubber flange 222 is provided with a rubber boss 223, which prevents abnormal noise caused by contact with surrounding parts.

[0046] The continuous structure of the rubber main spring 22 and the bonding design of the upper rubber flange 222 and the lower rubber flange 224 provide a larger bonding area and a more uniform stress distribution, good vulcanization processability, high bonding strength and long service life.

[0047] The rubber boss 223 avoids hard contact with surrounding parts, thus preventing abnormal noises that may be caused by friction.

[0048] The rubber main spring 22 has stop blocks 225 at the flat surface 111 and the bulge 112 of the corresponding plastic bracket 1. The rubber elastic deformation reduces the impact between the metal inner core 21 and the plastic bracket 1. The stop blocks 225 on the rubber main spring 22 can preferentially undergo elastic deformation under extreme impact, effectively buffering the hard impact between the metal inner core 21 and the plastic bracket 1, and improving durability and comfort.

[0049] Due to the different shrinkage rates of plastic and metal, the plastic surface after injection molding is usually lower than the surface of the metal insert 3. The height of the metal insert 3 is higher than that of the plastic bracket 1. The plastic bracket 1 has a full-circle surrounding part 14 in the higher part to prevent the metal insert 3 from being exposed in the height direction. The metal insert 3 is cylindrical and has a through hole 31 in the middle.

[0050] In one embodiment, the through hole 31 can be configured in different shapes, such as a round hole, a U-shaped hole, or a round hole with a notch, to eliminate vehicle installation tolerances. The direction of the through hole 31 is the same as the direction of the second inner hole 12.

[0051] The metal insert 3 has a groove 33 in the middle and arc-shaped notches 32 arranged around its outer edges at both ends. After integral injection molding, the metal insert 3 is fixed to the second inner hole 12 of the plastic bracket 1. The plastic fills the arc-shaped notches 32 and the groove 33, forming a structural interlock between the metal insert 3 and the plastic bracket 1. This ensures that the metal insert 3 and the plastic bracket 1 will not loosen under long-term high loads, and the connection reliability far exceeds that of methods that rely solely on adhesive force.

[0052] A method for integral injection molding of a plastic motor suspension assembly includes the following steps: The plastic support 1 and the rubber body 2 were modeled using 3D software; Using simulation software, the rubber material parameters of rubber body 2 are imported, and the vulcanization and cooling process of rubber body 2 is simulated to obtain the deformation model of rubber body 2 after cooling. Based on the deformation model of rubber body 2, the sliding mechanism of the injection mold is designed and processed by contouring. The rubber body 2 and the metal insert 3 are placed in the injection mold as an inner skeleton, and the sliding mechanism is supported in the hollow part of the rubber body 2. The injection molding machine performs injection molding, and the suspension assembly is obtained after injection molding. The suspension assembly after injection molding is scanned by X-ray scanning equipment to obtain an image of the suspension assembly. The injection molding process is adjusted based on the image, and then injection molding is performed again. Repeat the previous step until the rubber at the support leg 221 of the rubber body 2 in the image is no longer compressed, thus obtaining a qualified suspension assembly and completing the injection molding process.

[0053] Determine whether the rubber at the support leg 221 of the rubber body 2 is being compressed based on the image; Before the rubber body 2 is placed into the injection mold, an adhesive is applied to the outer wall surface of the rubber body 2 to improve the product strength.

[0054] The sliding mechanism can support the hollow part of the rubber body 2, preventing deformation of the hollow part. Since the support leg 221 of the rubber body 2 is solid, the sliding mechanism cannot provide support for the support leg 221. During injection molding, the plastic will still compress the rubber at the support leg 221. Using X-ray scanning equipment, the internal structure can be quickly and accurately observed next to the injection molding machine, allowing for optimization of the injection molding process. This enables observation of the internal structure of the suspension assembly during injection molding, allowing for process adjustments without stopping the machine, reducing the number of trial productions, and saving development costs and time.

[0055] Simulation software was used to model the deformation of rubber after vulcanization and cooling, and the mold's sliding mechanism was designed and machined based on this model. This reduced the risk and cost of trial and error in physical samples. X-ray scanning equipment was introduced for rapid, non-destructive internal inspection, allowing direct visualization of critical components such as support leg 221 to see if they were damaged by injection pressure, enabling data-driven and precise process adjustments. Through rapid iteration of "scan-judgment-adjustment-re-injection," a real-time process optimization closed loop was formed, enabling process adjustments without stopping the machine and significantly reducing the number of repeated mold repairs and trials in traditional development. The finalized injection molding process became the core guarantee for stable production of high-quality products, ensuring product consistency and reliability.

[0056] The above description is an explanation of this application and not a limitation thereof. The scope of this application is defined by the claims. Within the scope of protection of this application, any form of modification may be made.

Claims

1. A plastic motor suspension assembly, characterized in that, include: The plastic bracket (1) includes a first inner hole (11) and a second inner hole (12); The rubber body (2) is located in the first inner hole (11); The metal insert (3) is located in the second inner hole (12); Among them, the rubber body (2) and the metal insert (3) are placed in the injection mold as an inner skeleton and integrally injection molded with the plastic bracket (1); Two straight surfaces (111) are symmetrically arranged inside the first inner hole (11), and two bulges (112) are also arranged inside the first inner hole (11), with the straight surfaces (111) and bulges (112) spaced apart; The rubber body (2) includes a metal inner core (21) and a rubber main spring (22). The metal inner core (21) is provided with a boss (211) corresponding to the flat surface (111) and a raised part (212) corresponding to the bulge (112).

2. A symmetrical plastic motor suspension assembly as described in claim 1, characterized in that: The plastic bracket (1) has a barrier (13) outside the second inner hole (12). The inner diameter of the barrier (13) is larger than the diameter of the second inner hole (12), and the lower surface of the barrier (13) is lower than the upper surface of the second inner hole (12).

3. The plastic motor suspension assembly as described in claim 2, characterized in that: The metal insert (3) is higher than the plastic bracket (1), and the plastic bracket (1) is provided with a full circle of surrounding portion (14) in the higher portion.

4. The plastic motor suspension assembly as described in claim 1, characterized in that: The rubber main spring (22) has multiple support legs (221) arranged in the middle.

5. A plastic motor suspension assembly as described in claim 1, characterized in that: The metal insert (3) has a through hole (31) in the middle, a groove (33) in the middle, and arc-shaped notches (32) arranged in a circle on the outer edges of both ends of the metal insert (3).

6. The plastic motor suspension assembly as described in claim 1, characterized in that: The first inner hole (11) and the second inner hole (12) penetrate the plastic bracket (1) in different directions.

7. A plastic motor suspension assembly as described in claim 1, characterized in that: The plastic bracket (1) is made of nylon fiberglass.

8. A plastic motor suspension assembly as described in claim 1, characterized in that: The rubber main spring (22) has an upper rubber flange (222) and a lower rubber flange (224). The upper rubber flange (222) and the lower rubber flange (224) are coated with adhesive. The upper rubber flange (222) and the lower rubber flange (224) are bonded to the plastic bracket (1) as a whole. The upper rubber flange (222) is provided with a rubber boss (223).

9. A plastic motor suspension assembly as described in claim 8, characterized in that: The rubber main spring (22) has a stop block (225) at the flat surface (111) and the bulge (112) of the corresponding plastic bracket (1).

10. A method for integral injection molding of a plastic motor suspension assembly, characterized in that, Includes the following steps: The first step is to use 3D software to model the plastic support (1) and the rubber body (2); The second step is to use simulation software to import the rubber material parameters of the rubber body (2), simulate the vulcanization and cooling process of the rubber body (2), and obtain the deformation model of the cooled rubber body (2). The third step is to design and process the sliding mechanism of the injection mold based on the deformation model of the rubber body (2). The fourth step is to place the rubber body (2) and the metal insert (3) as the inner skeleton into the injection mold, and the sliding mechanism is supported in the hollow part of the rubber body (2); The fifth step involves injection molding, which produces the suspension assembly. The sixth step is to scan the injection-molded suspension assembly with an X-ray scanning device to obtain an image of the suspension assembly. The injection molding process is then adjusted based on the image, and injection molding is performed again after the adjustment. Step 7: Repeat step 6 until the rubber at the support leg (221) of the rubber body (2) in the image is no longer squeezed, and a qualified suspension assembly is obtained, and the injection molding process is cured.

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