Integrated injection molding device for automobile bumper with anti-deformation secondary ejection mechanism

Abstract

The application relates to an automobile bumper integrated injection molding device with a deformation prevention secondary ejection mechanism and belongs to the field of automobile part manufacturing equipment. The device comprises a female die, a male die, a first ejection mechanism and a second ejection mechanism. A cavity is arranged in the female die. The male die is combined with the female die to form an injection cavity chamber matched with an injection product. A plurality of concave cavities are arranged in the female die, the first ejection mechanism is arranged in the cavity, and the second ejection mechanism is arranged in the concave cavity. The application has the beneficial effect that the first ejection mechanism and the second ejection mechanism are arranged, so that the formed automobile bumper can be ejected in stages during demolding. Compared with the traditional one-time ejection mode, the secondary ejection can avoid the ejection force from being concentrated on the local area of the product in a short time, thereby reducing the risk of the bumper warping, bending, locally sinking or overall deforming.

Description

Technical Field

[0001] This invention relates to the field of automotive parts manufacturing equipment, specifically to an integrated injection molding apparatus for automotive bumpers with a secondary ejection mechanism to prevent deformation. Background Technology

[0002] Car bumpers are important components of a car's exterior trim system, typically characterized by their large size, relatively thin walls, complex curved surfaces, numerous reinforcing ribs, and mounting clips. Most existing car bumpers are manufactured using injection molding, which involves injecting molten plastic into a cavity formed by a male and female mold using an injection molding device. After pressure holding and cooling to set the shape, the mold is opened, and the finished bumper is ejected from the mold by an ejector mechanism.

[0003] However, due to the large overall span of automotive bumpers and the fact that their surfaces are typically cosmetic, high requirements are placed on dimensional accuracy, surface quality, and assembly consistency. In actual demolding, if only a traditional single-ejection mechanism is used, the ejection force is often concentrated on a localized area of ​​the product, easily leading to uneven stress on the bumper at the moment of demolding. This can result in defects such as warping, deformation, whitening, tearing, or localized stress concentration. This is especially true for bumper products with deep cavity structures, inverted structures, thin-walled structures, or multi-curved transition structures, where a single ejection method cannot simultaneously achieve both demolding efficiency and the need to prevent product deformation.

[0004] Furthermore, during the injection molding process of bumpers, the product cools and shrinks, creating significant adhesion or clamping forces with the local surfaces of the punch or die. If rigid ejection is performed directly after mold opening, the bumper is susceptible to instantaneous impact loads, resulting in localized bending or overall dimensional deviations. For one-piece injection-molded car bumpers, multiple mounting structures, connecting structures, and reinforcing structures are typically molded simultaneously with the bumper body. The demolding resistance varies across different areas during demolding, further increasing the risk of ejection deformation.

[0005] Therefore, there is an urgent need to provide an integrated injection molding device for automotive bumpers with a secondary ejection mechanism to reduce the concentrated stress and impact force on the product during the demolding process, reduce deformation and damage, and improve the integrated injection molding quality and production efficiency of automotive bumpers. Summary of the Invention

[0006] The summary section of this application is intended to provide a brief overview of the concepts, which will be described in detail in the detailed description section below. This summary section is not intended to identify key or essential features of the claimed technical solutions, nor is it intended to limit the scope of the claimed technical solutions.

[0007] To address the technical problems mentioned in the background section above, some embodiments of this application provide an integrated injection molding device for automotive bumpers with an anti-deformation secondary ejection mechanism, comprising: a cavity, a punch, a first ejection mechanism, and a second ejection mechanism; the cavity is provided with a cavity; the punch and the cavity are closed to form an injection molding chamber that matches the injection molded product; the cavity is further provided with multiple cavities, the first ejection mechanism is disposed in the cavity, and the second ejection mechanism is disposed in the cavity.

[0008] Furthermore, the second ejection mechanism includes an ejector rod and a top mold disposed on the end face of the ejector rod, the top mold forming part of the bottom surface of the cavity.

[0009] Furthermore, a fixed shell is provided on the outer wall of the ejector rod, and a slanted pushing mechanism is provided on the fixed shell. The slanted pushing mechanism has an ejection state and a retraction state. The size of the fixed shell is smaller than the size of the top mold. When the slanted pushing mechanism is in the ejection state, the slanted pushing mechanism is at least partially located above the outside of the top mold. When the slanted pushing mechanism is in the retraction state, the slanted pushing mechanism is located below the top mold and is retracted within the outer contour of the top mold.

[0010] Furthermore, the push rod has a flow channel groove inside, and the outer wall of the push rod has multiple through holes communicating with the flow channel groove; the flow channel groove is connected to a pump body mechanism, and the inclined push mechanism is directly or indirectly connected to the through holes; the pump body mechanism injects and extracts fluid into and from the flow channel groove, so that the inclined push mechanism switches between the pushed-out state and the retracted state.

[0011] Furthermore, the inclined pushing mechanism includes multiple sleeves that are sealed to each other, and the multiple sleeves are slidably connected to each other; the sleeves are inserted into the through hole; and a sealing plate is provided at the end of the sleeve away from the through hole.

[0012] Furthermore, a flexible or elastic pad is provided on the sealing plate.

[0013] Furthermore, the inclined pushing mechanism includes a flexible membrane and an elastic membrane; an opening is provided at the upper end of the fixed shell; the flexible membrane is connected to the opening, and the elastic membrane is connected to the flexible membrane; a through groove is provided on the fixed shell, and the through groove is connected to the through hole.

[0014] Furthermore, the structure of the first ejection mechanism is the same as that of the second ejection mechanism.

[0015] Furthermore, the pump body mechanism includes an injection pump, a return pump, a heating element, and a cooling element; the injection pump injects fluid into the fluid tank, and the return pump draws fluid out of the fluid tank; both the injection pump and the return pump are externally connected to a fluid storage tank; the heating element and the cooling element are both located in the fluid storage tank.

[0016] Furthermore, the fluid is a liquid or air.

[0017] The beneficial effects of this invention are: This application, by setting up a first ejection mechanism and a second ejection mechanism, enables the molded car bumper to be ejected in stages during the demolding process. Compared with the traditional one-time ejection method, the two-stage ejection can avoid the ejection force being concentrated on a local area of ​​the product in a short period of time, thereby reducing the risk of the bumper warping, bending, local denting, or overall deformation.

[0018] Traditional rigid ejection methods are prone to defects such as white spots, scratches, and indentations on the surface or back of the bumper. This application uses a secondary ejection mechanism to assist in demolding, which can reduce the pressure of a single ejection mechanism on local areas of the product, reduce ejection marks and local stress concentration, and improve the appearance quality of the finished bumper.

[0019] The fluid can be liquid or air. By involving liquid or air in the ejection, cushioning, support, or assisted demolding process, the rigid impact between the ejection mechanism and the product can be further reduced, resulting in a softer force distribution effect on the bumper during demolding, thereby further improving its anti-deformation ability. Attached Figure Description

[0020] The accompanying drawings, which form part of this application, are used to provide a further understanding of the application and to make other features, objects, and advantages of the application more apparent. The illustrative embodiments and descriptions of this application are used to explain the application and do not constitute an undue limitation of the application.

[0021] Furthermore, throughout the accompanying drawings, the same or similar reference numerals denote the same or similar elements. It should be understood that the drawings are schematic, and the elements are not necessarily drawn to scale.

[0022] In the attached diagram: Figure 1 This is a schematic diagram of the overall structure of an embodiment of this application; Figure 2 for Figure 1 A schematic diagram of the bottom structure; Figure 3 for Figure 1 A partial sectional view of the structure; Figure 4 for Figure 3 Enlarged diagram of A in the middle; Figure 5 This is a schematic diagram of the first ejection mechanism; Figure 6 A schematic diagram of the structure of the multi-section sleeve and some surrounding parts; Figure 7 for Figure 6 Enlarged diagram of B in the diagram; Figure 8 This is a structural schematic diagram of the flexible membrane, the elastic membrane, and some surrounding parts. Figure 9 for Figure 8 Enlarged diagram of C in the middle; Figure 10 This is a structural diagram of the hinge rod, the limiting rod, and some surrounding parts. Figure 11 A structural schematic diagram of an integrated injection-molded automotive bumper product; Figure 12 This is a schematic diagram of the structure of an integrated injection molded automotive bumper and its cavity.

[0023] The annotations in the attached figures are explained as follows: 1. Cavity; 11. Cavity; 12. Cavity; 2. Punch; 3. First ejector mechanism; 31. Ejector pin; 311. Runner; 312. Through hole; 32. Ejector mold; 33. Fixed shell; 331. Mounting groove; 34. Inclined push mechanism; 341. Multi-section sleeve; 342. Flexible pad; 343. Flexible membrane; 344. Elastic membrane; 345. Hinge rod; 346. Limiting rod; 35. Pump body mechanism; 351. Injection pump; 352. Return pump; 353. Fluid storage tank; 4. Second ejector mechanism; 5. Integrated injection molded automotive bumper product. Detailed Implementation

[0024] Embodiments of this disclosure will now be described in more detail with reference to the accompanying drawings. While some embodiments of this disclosure are shown in the drawings, it should be understood that this disclosure can be implemented in various forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of this disclosure. It should be understood that the accompanying drawings and embodiments of this disclosure are for illustrative purposes only and are not intended to limit the scope of protection of this disclosure.

[0025] It should also be noted that, for ease of description, only the parts relevant to the invention are shown in the accompanying drawings. Unless otherwise specified, the embodiments and features described in this disclosure can be combined with each other.

[0026] It should be noted that the concepts of "first" and "second" mentioned in this disclosure are used only to distinguish different devices, modules or units, and are not used to limit the order of functions performed by these devices, modules or units or their interdependencies.

[0027] It should be noted that the terms "a" and "a plurality of" used in this disclosure are illustrative rather than restrictive, and those skilled in the art should understand that, unless otherwise expressly indicated in the context, they should be understood as "one or more".

[0028] This disclosure will now be described in detail with reference to the accompanying drawings and embodiments.

[0029] Reference Figures 1-12 As shown, the integrated injection molding device for automobile bumpers with anti-deformation secondary ejection mechanism described in this invention can be used for large thin-walled plastic parts, especially suitable for the molding and demolding of integrated injection molded products such as automobile bumpers, bumper trim panels, bumper brackets, or auxiliary structures such as buckles, connecting buckles, reinforcing ribs, and grooves.

[0030] Automotive bumper products are typically characterized by large size, thin wall thickness, complex structure, and the presence of undercuts or deep ribs. In existing single-ejection structures, if the ejector pin 31 directly acts on the main body of the product or some auxiliary structures, it can easily cause concentrated ejection force, leading to problems such as whitening, cracking, local warping, buckle deformation, or breakage of connectors. Therefore, this application utilizes the cooperation of the first ejection mechanism 3 and the second ejection mechanism 4 to achieve zoned ejection, segmented ejection, and flexible or buffered ejection, thereby reducing the localized stress on the product during a single ejection and improving the demolding integrity and dimensional stability of the injection molded product.

[0031] In some cases, existing car bumpers are injection molded separately for the upper and lower bumpers. This application can directly apply the injection molding of the upper and lower bumpers as a single unit. Since the removal of the parts increases after the parts are molded as a single unit, the secondary ejection removal of the parts in this application can better complete the removal operation. Example

[0032] This embodiment provides an integrated injection molding device for automotive bumpers with a secondary ejection mechanism to prevent deformation.

[0033] The integrated injection molding apparatus for automotive bumpers includes a cavity 1, a punch 2, a first ejection mechanism 3, and a second ejection mechanism 4. The cavity 1 has a cavity 11. The punch 2 can close with the cavity 1, forming an injection chamber that matches the shape of the injection-molded product. After the injection material enters the injection chamber, it cools and solidifies within the chamber to form the integrated injection-molded automotive bumper product 5.

[0034] The die 1 also includes multiple cavities 12. These cavities 12 correspond to the molding positions of snap-fit ​​parts, connecting clips, mounting ears, positioning protrusions, local reinforcing ribs, deep cavity structures, or other small auxiliary parts on the injection molded product. In other words, the cavities 12 are used to form small, localized structures attached to the main body of the car bumper. These structures are typically small in size, thin in wall thickness, and have a large clamping force with the mold. If forced ejection is used in one go, it can easily cause localized deformation or breakage.

[0035] The first ejection mechanism 3 is positioned corresponding to the cavity 11 and is used to eject the main body of the injection-molded product. The second ejection mechanism 4 is positioned corresponding to the cavity 12 and is used to eject small auxiliary parts such as clips and connectors from the injection-molded product. Through the cooperation of the first ejection mechanism 3 and the second ejection mechanism 4, the main body of the injection-molded product and the small auxiliary parts can be subjected to force separately, avoiding the concentration of all ejection forces on a localized area of ​​the product.

[0036] In a specific ejection process, after the mold has cooled, it opens first, separating the punch 2 from the die 1. Then, the first ejection mechanism 3 actuates, ejecting the main body of the injection-molded product from the cavity 11, causing the main body of the product to detach from or at least partially detach from the wall of the cavity 11. Afterwards, the second ejection mechanism 4 actuates, ejecting small auxiliary parts such as clips and connectors located in the cavity 12. Since the main body has already been supported and moved by the first ejection mechanism 3, the second ejection mechanism 4 only needs to perform localized demolding assistance on the auxiliary structures. Therefore, it can significantly reduce the demolding resistance between the auxiliary structures and the cavity 12, reducing the risks of jamming, tearing, whitening, and deformation.

[0037] In this embodiment, the second ejection mechanism 4 includes an ejector rod 31 and an ejector mold 32 disposed on the end face of the ejector rod 31. The ejector mold 32 forms part of the bottom surface of the cavity 12. That is, during the injection molding process, the ejector mold 32 is used not only as an ejector component, but also participates in product molding as part of the molding surface of the cavity 12. Since the ejector mold 32 has a large contact area with the attached small parts, when the ejector rod 31 drives the ejector mold 32 to move outward, the ejector mold 32 can push the attached small parts in a surface contact or near-surface contact manner, rather than directly acting on a local position of the product through a single point-like or line-like ejector rod 31. As a result, the ejection pressure per unit area can be reduced, avoiding damage or whitening marks on the attached small parts.

[0038] Furthermore, the outer contour of the top mold 32 can match the contour of the corresponding part in the bottom surface of the cavity 12. When the mold is closed and injection molding is performed, the top mold 32 is in its initial position, and the upper surface of the top mold 32 and other bottom surface areas of the cavity 12 together define the complete bottom surface of the cavity 12. When ejection is required, the ejector pin 31 drives the top mold 32 to move in a preset direction, and the top mold 32 drives the auxiliary small parts located in the cavity 12 to move outward, so that the auxiliary small parts first create a separation gap between themselves and the wall of the cavity 12.

[0039] This application uses a first ejection mechanism 3 and a second ejection mechanism 4 to replace the push rod in the traditional mold ejection. The driving force of the first ejection mechanism 3 and the second ejection mechanism 4 to eject outward can be directly the same as the driving force of the push rod to eject outward in the traditional mold, or an additional cylinder or hydraulic cylinder can be added for driving. This will not be described in detail. Example

[0040] This embodiment further explains the second ejection mechanism 4 based on Embodiment 1.

[0041] The second ejection mechanism 4 includes an ejector rod 31, an ejector mold 32, and a fixed shell 33. The ejector mold 32 is disposed on the end face of the ejector rod 31, and the fixed shell 33 is disposed on the outer wall of the ejector rod 31. A slanting push mechanism 34 is disposed on the fixed shell 33. The slanting push mechanism 34 has an ejected state and a retracted state.

[0042] The size of the fixed shell 33 is smaller than that of the top mold 32. Specifically, the outer contour size of the fixed shell 33 in the direction perpendicular to the axis of the ejector pin 31 is smaller than that of the top mold 32, so that when the inclined push mechanism 34 is in the retracted state, the inclined push mechanism 34 can be housed within the outer contour of the top mold 32, avoiding interference with the molding surface of the cavity 12 during mold closing or injection molding.

[0043] When the angled push mechanism 34 is in the ejected state, it is at least partially located above the outside of the top mold 32. "Above" here can be understood as the side facing the injection-molded product or the opening of the cavity 12. In the ejected state, the angled push mechanism 34 can extend at an angle relative to the ejector pin 31, thereby applying a further separation force to the auxiliary small part already lifted by the top mold 32, causing the auxiliary small part to detach from the top mold 32.

[0044] When the inclined push mechanism 34 is in the retracted state, it is located below the top mold 32 and is retracted within the outer contour of the top mold 32. At this time, the inclined push mechanism 34 will not protrude beyond the outer side of the molding surface of the top mold 32, nor will it affect the molding quality of the injection molded product.

[0045] The working process of this embodiment may include the following steps.

[0046] The first step is to open the mold between the cavity mold 1 and the punch mold 2 after the injection molding is completed and cooled.

[0047] In the second step, the first ejection mechanism 3 is activated to eject the main body of the car bumper from the cavity 11 of the die 1, so that the main body is separated from the wall of the cavity 11.

[0048] In the third step, the ejector rod 31 in the second ejection mechanism 4 actuates, driving the ejector mold 32 to eject outward. Since the ejector mold 32 forms part of the bottom surface of the cavity 12, it can support the attached small parts, causing the attached small parts to at least partially detach from the bottom surface or side wall of the cavity 12. This process belongs to the first stage of partial ejection.

[0049] Fourth, the inclined push mechanism 34 switches from the retracted state to the ejected state. The inclined push mechanism 34 extends obliquely relative to the ejector rod 31, and at least partially extends to the outside or above the ejector mold 32, applying an oblique or partial auxiliary ejection force to the auxiliary small part. Through this oblique auxiliary ejection force, the auxiliary small part is further disengaged from the ejector mold 32. This process belongs to the second stage of auxiliary ejection.

[0050] Fifth step: After the product is completely detached, the inclined push mechanism 34 resets to the retracted state, and the ejector rod 31 and the ejector mold 32 retract to the initial position, waiting for the next injection cycle.

[0051] By using the segmented ejection method described above, the demolding process, which was originally completed in one step by a single ejector pin 31 or a single ejector mold 32, can be broken down into multiple stages. The ejector mold 32 first disengages the auxiliary small parts from the cavity 12, and then the inclined push mechanism 34 disengages the auxiliary small parts from the ejector mold 32. This effectively reduces the concentrated stress at the moment of ejection and avoids product deformation caused by excessive demolding area or excessive demolding resistance. Example

[0052] This embodiment describes the driving structure of the inclined push mechanism 34 based on embodiment 2.

[0053] The push rod 31 has a flow channel groove 311 inside, and multiple through holes 312 communicating with the flow channel groove 311 are provided on the outer wall of the push rod 311. The flow channel groove 311 is externally connected to the pump body mechanism 35, and the inclined push mechanism 34 is directly or indirectly connected to the through holes 312. The pump body mechanism 35 can inject fluid into the flow channel groove 311 and also can extract fluid from the flow channel groove 311, thereby allowing the inclined push mechanism 34 to switch between the push state and the retract state.

[0054] Specifically, when the pump body mechanism 35 injects fluid into the flow channel groove 311, the fluid enters the through hole 312 through the flow channel groove 311 and further acts on the inclined push mechanism 34, causing the inclined push mechanism 34 to extend outward. When the pump body mechanism 35 withdraws fluid from the flow channel groove 311, the inclined push mechanism 34 retracts under its own rebound force, external reset structure, or negative pressure, thereby switching to the retracted state.

[0055] The fluid can be either liquid or air. When the fluid is liquid, the inclined push mechanism 34 can be hydraulically driven, which has the advantages of stable driving force and large pushing force, and is suitable for scenarios where the clamping force of the auxiliary structure is large or a strong auxiliary ejection force is required. When the fluid is air, the inclined push mechanism 34 can be pneumatically driven, which has the advantages of fast response speed, high system cleanliness, and simple structure, and is suitable for scenarios where the ejection force requirement is relatively small or a rapid circulation is required.

[0056] The number of through holes 312 can be set according to the number, size, and force requirements of the auxiliary small parts. For example, for a long connecting buckle structure, multiple through holes 312 can be set circumferentially or axially on the outer wall of the ejector pin 31, and multiple inclined push mechanisms 34 can be arranged accordingly to achieve multi-point synchronous ejection. For a smaller snap-fit ​​structure, one or two inclined push mechanisms 34 can meet the auxiliary demolding requirements. Example

[0057] This embodiment provides a specific structure of the inclined push mechanism 34.

[0058] The inclined push mechanism 34 includes multiple sleeve sections that are sealed to each other, and the multiple sleeve sections 341 are slidably connected to each other. The sleeves are inserted into the through holes 312 on the outer wall of the push rod 31. A sealing plate is provided at the end of the sleeve away from the through holes 312.

[0059] The multi-section sleeve 341 can be configured to resemble a telescopic rod. A sealing structure, such as a sealing ring, sealing lip, or other annular seal, is provided between adjacent sleeves to prevent fluid leakage between them. When fluid enters the sleeve through the flow channel 311 and through-hole 312, the fluid pressure pushes the multi-section sleeve 341 to extend sequentially, causing the sealing plate to move outward. Because the through-hole 312 can be inclined relative to the axis of the push rod 31, the multi-section sleeve 341 can extend in an oblique pushing motion.

[0060] The sealing plate is used to increase the contact area between the inclined push mechanism 34 and the injection molded product. Compared with directly pushing the product through small rods, the sealing plate can distribute the inclined push force to a larger contact area, further reducing the probability of local pressure deformation of the product.

[0061] Furthermore, a flexible pad 342 or an elastic pad can be provided on the sealing plate. The flexible pad 342 or the elastic pad can be made of silicone, rubber, high-temperature resistant elastic material, or other materials with cushioning properties. When the sealing plate comes into contact with the injection-molded product, the flexible pad 342 or the elastic pad can produce a certain elastic deformation, thereby buffering the impact force and preventing the sealing plate from directly contacting the product surface, which could cause indentations, whitening, or scratches.

[0062] In actual use, the top mold 32 first ejects the auxiliary small part, creating a local gap between the auxiliary small part and the cavity 12. Then, the pump mechanism 35 injects fluid into the flow channel 311. Under pressure, the multi-section sleeve 341 extends at an angle, and the sealing plate and its flexible pad 342 or elastic pad contact the auxiliary small part, pushing it away from the top mold 32. Once the auxiliary small part is completely detached, the pump mechanism 35 withdraws the fluid, and the multi-section sleeve 341 retracts into the fixed shell 33, thus avoiding interference with mold reset and the next mold closing. Example

[0063] This embodiment provides another specific structure for the inclined push mechanism 34.

[0064] The inclined pushing mechanism 34 includes a flexible membrane 343 and an elastic membrane 344. An opening is provided at the upper end of the fixed housing 33. The flexible membrane 343 is connected to the opening, and the elastic membrane 344 is connected to the flexible membrane 343. A through groove is provided on the fixed housing 33, and the through groove is connected to a through hole 312 on the outer wall of the push rod 31.

[0065] After the pump body mechanism 35 injects fluid into the flow channel 311, the fluid sequentially passes through the flow channel 311, through hole 312, and through groove into the fixed shell 33, and acts on the elastic membrane 344. The elastic membrane 344 expands under the fluid pressure. Since the flexible membrane 343 is connected to the opening at the upper end of the fixed shell 33, the flexible membrane 343 can constrain the expansion direction of the elastic membrane 344, causing the elastic membrane 344 to expand more towards the outside of the opening, that is, towards the outside or above the top mold 32. After expansion, the elastic membrane 344 contacts the small auxiliary parts of the injection molded product and applies a flexible auxiliary ejection force to the small auxiliary parts, causing them to separate from the top mold 32.

[0066] In this embodiment, the expansion of the elastic membrane 344 achieves assisted ejection, which has a better buffering effect compared to ejection by rigid rods. The elastic membrane 344 can adapt to the local shape of the product, making it suitable for bumper attachments with high surface quality requirements, thin walls, or complex local structures.

[0067] Furthermore, the flexible membrane 343 can be used to limit the disorderly expansion of the elastic membrane 344, preventing the elastic membrane 344 from excessively deforming into the fixed shell 33 or in the non-ejection direction, thereby improving the effective utilization rate of the ejection force. The flexible membrane 343 can be made of a material with certain flexibility and temperature resistance, such as a high-temperature resistant composite membrane, rubber membrane, silicone membrane, or reinforced elastic sheet. The elastic membrane 344 can be made of a material with good elastic recovery ability, enabling it to automatically retract after the fluid is extracted.

[0068] In one optional structure, the opening of the fixed shell 33 is provided with a mounting groove 331, and a plurality of hinge rods 345 are hingedly disposed in the mounting groove 331, the hinge rods 345 being fixedly connected to the flexible membrane 343. A limit rod 346 is also provided on the mounting groove 331, the limit rod 346 being used to limit the unfolding angle of the hinge rods 345.

[0069] When the inclined push mechanism 34 is in the retracted state, multiple hinge rods 345 close together, and the flexible membrane 343 and elastic membrane 344 are housed within the fixed shell 33 or the outer contour of the ejector mold 32. When the inclined push mechanism 34 is in the ejected state, the elastic membrane 344 expands under fluid pressure, causing the flexible membrane 343 to unfold, and the multiple hinge rods 345 rotate outward as the flexible membrane 343 unfolds. The limiting rod 346 restricts the unfolding angle of the hinge rods 345, preventing them from continuing to unfold after reaching a preset angle. At this time, the hinge rods 345 can provide support for the flexible membrane 343, ensuring that the elastic membrane 344 has sufficient reaction support when it expands and contacts the injection molded product, preventing the elastic membrane 344 from failing to effectively eject the product due to insufficient support. This structure can balance flexible contact and reliable support, protecting the surface of the injection molded product while improving the stability of the auxiliary ejection action.

[0070] Based on any of the above embodiments, the structure of the first ejection mechanism 3 can be the same as the structure of the second ejection mechanism 4.

[0071] In other words, the first ejection mechanism 3 may also include an ejector rod 31, an ejector mold 32, a fixed shell 33, and a slanted push mechanism 34. A flow channel 311 may be provided inside the ejector rod 31, and a through hole 312 may be provided on the outer wall of the ejector rod 31. The slanted push mechanism 34 achieves ejection and retraction through fluid pressure. The first ejection mechanism 3 is used to eject the main body of the car bumper, and the second ejection mechanism 4 is used to eject small auxiliary parts such as clips and connecting buckles.

[0072] When the first ejection mechanism 3 and the second ejection mechanism 4 adopt the same structure, the timing of their actions can be controlled separately by a control system. For example, the first ejection mechanism 3 can act first to support and eject the main body of the product, and the second ejection mechanism 4 can then act to assist in the demolding of auxiliary small parts. Alternatively, depending on the product structure requirements, the first ejection mechanism 3 and the second ejection mechanism 4 can be partially synchronized, with the oblique push mechanism 34 of the second ejection mechanism 4 providing delayed assistance in ejection.

[0073] By setting the first ejection mechanism 3 and the second ejection mechanism 4 to the same or similar structure, the versatility of mold components can be improved, and processing and maintenance costs can be reduced. At the same time, for local deep ribs or thin-walled areas in the main body of the car bumper, the oblique push mechanism 34 of the first ejection mechanism 3 can also provide a flexible or segmented auxiliary ejection effect, thereby further reducing the risk of product deformation.

[0074] Based on the above embodiments, the pump body mechanism 35 includes an injection pump 351, a return pump 352, a fluid storage tank 353, a heating element, and a cooling element. The injection pump 351 is used to inject fluid from the fluid storage tank 353 into the flow channel 311, and the return pump 352 is used to extract fluid from the flow channel 311 and return it to the fluid storage tank 353. Both the heating element and the cooling element are disposed in the fluid storage tank 353.

[0075] The injection pump 351 and the return pump 352 can be connected to the flow channel 311 via pipelines. To facilitate control of the fluid flow direction, solenoid valves, check valves, proportional valves, or pressure regulating valves can be installed on the pipelines. By controlling the start and stop of the injection pump 351 and the return pump 352, as well as the opening and closing of the relevant valves, the extension, holding, and retraction of the inclined push mechanism 34 can be achieved.

[0076] The heating element heats the fluid in the fluid storage tank 353, while the cooling element cools the fluid in the fluid storage tank 353. By coordinating the heating and cooling elements, the temperature of the fluid entering the runner 311 and the inclined push mechanism 34 can be adjusted, making the fluid temperature closer to the temperature at which the injection-molded product is demolded. This reduces uneven thermal expansion and contraction, increased surface stress, or dimensional deviations caused by excessive local temperature differences during the contact between the inclined push mechanism 34 and the product.

[0077] For example, when the car bumper has just cooled down but still retains some residual heat, the fluid can be heated to near the product temperature by a heating element, preventing localized sudden cooling when the inclined push mechanism 34 contacts the product. If the product temperature is low or rapid reset is required, the fluid temperature can be reduced by a cooling element to improve circulation efficiency. Both the heating and cooling elements are existing technologies; for example, the heating element is a heating tube, and the cooling element is a condenser.

[0078] In an alternative embodiment, a temperature sensor can also be provided. The temperature sensor can be used to detect the temperature of the injection-molded product, the mold temperature, or the fluid temperature within the fluid storage tank 353. The control system can control the operation of the heating and cooling elements based on the temperature sensor's detection results to maintain the fluid temperature within a preset range.

[0079] The above description is merely a selection of preferred embodiments of this disclosure and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the invention involved in the embodiments of this disclosure is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the above-described inventive concept. For example, technical solutions formed by substituting the above-described features with (but not limited to) technical features with similar functions disclosed in the embodiments of this disclosure.

Claims

1. An integrated injection molding device for automotive bumpers with a secondary ejection mechanism to prevent deformation, characterized in that, include: The mold includes a cavity, a punch, a first ejector mechanism, and a second ejector mechanism; the cavity has a molded cavity; the punch and the cavity close together to form an injection molding chamber that matches the injection molded product. The die is further provided with multiple cavities, the first ejection mechanism is provided in the cavity, and the second ejection mechanism is provided in the cavity.

2. The integrated injection molding device for automobile bumpers with anti-deformation secondary ejection mechanism according to claim 1, characterized in that: The second ejection mechanism includes an ejector rod and a top mold disposed on the end face of the ejector rod, the top mold forming part of the bottom surface of the cavity.

3. The integrated injection molding device for automobile bumpers with anti-deformation secondary ejection mechanism according to claim 2, characterized in that: A fixed shell is provided on the outer wall of the push rod, and a slanted push mechanism is provided on the fixed shell. The slanted push mechanism has an extended state and a retracted state. The size of the fixed shell is smaller than the size of the top mold. When the inclined push mechanism is in the ejection state, the inclined push mechanism is at least partially located above the outside of the top mold; when the inclined push mechanism is in the retraction state, the inclined push mechanism is located below the top mold and the inclined push mechanism is retracted within the outer contour of the top mold.

4. The integrated injection molding device for automobile bumpers with anti-deformation secondary ejection mechanism according to claim 3, characterized in that: The push rod has a flow channel groove inside, and the outer wall of the push rod has multiple through holes that communicate with the flow channel groove; The flow channel is externally connected to a pump body mechanism, and the inclined push mechanism is directly or indirectly connected to the through hole; the pump body mechanism injects and extracts fluid from the flow channel so that the inclined push mechanism switches between the ejection state and the retraction state.

5. The integrated injection molding device for automobile bumpers with anti-deformation secondary ejection mechanism according to claim 4, characterized in that: The inclined pushing mechanism includes multiple sleeves that are sealed to each other and are slidably connected to each other; the sleeves are inserted into the through hole; and a sealing plate is provided at the end of the sleeve away from the through hole.

6. The integrated injection molding device for automobile bumpers with anti-deformation secondary ejection mechanism according to claim 5, characterized in that: The sealing plate is provided with a flexible or elastic pad.

7. The integrated injection molding device for automobile bumpers with anti-deformation secondary ejection mechanism according to claim 4, characterized in that: The inclined pushing mechanism includes a flexible membrane and an elastic membrane; the upper end of the fixed shell is provided with an opening; the flexible membrane is connected to the opening, and the elastic membrane is connected to the flexible membrane; The fixed shell is provided with a through groove, which is connected to the through hole.

8. The integrated injection molding apparatus for automobile bumpers with anti-deformation secondary ejection mechanism according to any one of claims 1-7, characterized in that: The structure of the first ejection mechanism is the same as that of the second ejection mechanism.

9. The integrated injection molding device for automobile bumpers with anti-deformation secondary ejection mechanism according to claim 4, characterized in that: The pump body mechanism includes an injection pump, a return pump, a heating element, and a cooling element; the injection pump injects fluid into the fluid tank, and the return pump draws fluid out of the fluid tank; both the injection pump and the return pump are externally connected to a fluid storage tank; Both the heating element and the cooling element are located in the fluid storage tank.

10. The integrated injection molding apparatus for automobile bumpers with anti-deformation secondary ejection mechanism according to claim 9, characterized in that: The fluid is either a liquid or air.

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