Integrated injection molding and polishing mold for car lamp shell and variable-temperature forming process

Abstract

The invention belongs to the technical field of injection molding machines, and particularly relates to a car lamp shell integrated injection molding and polishing mold and a variable-temperature forming technology.The car lamp shell integrated injection molding and polishing mold comprises a front mold, a rear mold and a heating module, a cavity is formed in the rear mold, a spraying module is arranged in the cavity in a telescopic mode, and the spraying module is used for spraying a release agent to the inner wall of the cavity; the heating module is arranged in the rear mold, the heating module preheats the rear mold and evaporates release agent moisture sprayed on the inner wall of the mold cavity, the ejector pin module comprises an ejector pin plate and a plurality of ejector pins connected to the ejector pin plate, and the ejector pins penetrate through through holes in the rear mold and lead to the interior of the mold cavity. The spraying module is arranged on the side wall of the front end of the ejector pin, and the spraying module sprays a release agent to the inner wall of the cavity along with the action that the ejector pin retracts into the through hole; the situation that a first-time injection molding material and a second-time injection molding material cannot be well bonded due to improper spraying of a release agent can be avoided, and the stability of an injection molding product is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of injection molding machines, and in particular relates to an integrated injection molding and polishing mold for a vehicle lamp housing and a variable temperature molding process. Background Art

[0002] The variable temperature molding process is an advanced molding technology that combines multiple plastics of different temperatures, materials, and colors into a single product through single or multiple injection molding. It is mainly achieved through two-shot injection molding machines. Its core lies in the use of dedicated molds and dual-barrel injection molding equipment to achieve layer-by-layer material bonding under precise control. Two-shot injection molding machines are usually equipped with two independent barrel and nozzle systems, which can control the temperature, pressure, and injection speed of different materials respectively to ensure the compatibility of the two melts at the bonding interface; the mold design adopts a rotary, sliding, or turntable structure, and the cavity position is precisely switched through mechanical action. This allows the semi-finished product to be transferred to the second shot cavity after the first shot without demolding, thereby reducing the process interval and improving precision.

[0003] When producing automotive lamp housings through two-shot injection molding, these products typically have complex structures, high precision requirements, and strict surface smoothness standards. To reduce friction between the part and the mold and prevent scratches, deformation, and mold sticking, a release agent is added to ensure smooth release of the transparent part (such as PMMA or PC) from the first injection molding process, facilitating subsequent transfer and coating operations. The use of a release agent can, to a certain extent, protect the product's surface quality and improve production efficiency.

[0004] However, improper use of release agents during two-shot injection molding also carries certain risks. Since spraying release agents requires manual labor, improperly controlling the spraying range can leave residue on the mating surfaces of the two injection molding materials, forming a "separation layer" that prevents the second injection molding material from properly bonding to the first. This can lead to defects such as poor bonding, delamination, and peeling, compromising the long-term reliability of the product. Based on this, an integrated injection and polishing mold for headlight housings and a variable temperature molding process were proposed. Summary of the Invention

[0005] In order to solve the above problems existing in the prior art, the present invention provides an integrated injection polishing mold for a vehicle lamp housing and a variable temperature molding process.

[0006] The purpose of the present invention can be achieved through the following technical solutions: An integrated injection polishing mold for a headlight housing according to the present invention comprises a front mold, a rear mold and a first heating module. A cavity is formed in the rear mold. A spraying module is telescopically arranged in the cavity. The spraying module is used to spray a release agent onto the inner wall of the cavity. The first heating module is arranged in the rear mold. The first heating module preheats the rear film and evaporates the moisture of the release agent sprayed on the inner wall of the cavity.

[0007] Furthermore, it also includes a flip assembly and an ejector module, the rear mold is slidably arranged on the flip assembly, the ejector module is arranged on the flip assembly, the ejector module includes an ejector plate and a plurality of ejectors connected to the ejector plate, the plurality of ejectors pass through the through holes on the rear mold and lead to the mold cavity, the spray module is arranged on the front end side wall of the ejector, and the spray module sprays a release agent onto the inner wall of the mold cavity as the ejector retracts into the through hole.

[0008] Furthermore, the spray module includes several nozzles and a release agent tank, several of the nozzles are arranged on the front end side wall of the ejector, and the release agent tank is arranged outside the cavity. The nozzles and the release agent tank are connected through a water pipe, and the ejector retracts into the through hole and squeezes the nozzle to spray the release agent onto the inner wall of the cavity.

[0009] Furthermore, a groove is provided on the side wall at the front end of the ejector pin, and a spring is provided on the back side of the nozzle close to the front end of the ejector pin and connected to the groove. The nozzle is hinged to the edge of the groove on the side away from the front end of the ejector pin, and a valve is provided at the hinged position of the nozzle. The valve stem on the valve is connected to the outside of the nozzle and fixed in the ejector pin, and the valve channel forms an angle with the extension direction of the ejector pin, so that the valve is closed when the nozzle is fully tilted and completely parallel to the ejector pin, and the valve is opened when the nozzle is pressurized and rotates into the groove.

[0010] Furthermore, a cooling module is included, which includes a first cooling channel and a second cooling channel respectively arranged on the front mold and the rear mold, and the first cooling channel and the second cooling channel are both connected to a cooling water tank.

[0011] Furthermore, the front mold and the rear mold are provided with two groups of cavities, the ejector modules are provided with two groups corresponding to the two groups of cavities respectively, and the two groups of ejector modules are connected to the flip assembly.

[0012] Furthermore, a first hydraulic cylinder and a second hydraulic cylinder are respectively provided between the two groups of ejector modules and the flip assembly for pushing the ejector in the through hole to extend and retract.

[0013] Furthermore, it also includes a second heating module, which is arranged in the front mold and is used to heat the injection channel in the front mold and keep the material in a molten state.

[0014] Furthermore, an injection molding runner is provided on the front mold.

[0015] A variable temperature injection molding process for an integrated lamp housing includes the following steps: S1: Separate the front mold and the rear mold of the injection molding machine; S2: Spraying a water-based release agent onto the inner wall of the rear mold cavity of the injection molding machine through the extrusion nozzle when the ejector pin retracts; S3: The rear mold is heated to 80-120°C by the first heating module to evaporate the water of the water-based release agent adhering to the inner wall of the rear mold cavity and preheat the mold for 30-60 seconds; S4: After the water evaporates and the effective components of the water-based release agent adhere to the inner wall of the rear mold cavity, coolant is injected into the first cooling channel and the second cooling channel to cool the front mold and the rear mold to the injection temperature; S5: close the mold and perform the first injection. After the first injection is completed, separate the front mold and the rear mold and flip the rear mold through the flip assembly; S6: Clean the fitting surface between the shell and the rear mold, close the mold and perform the second injection molding; S7: Cooling liquid is injected into the first cooling channel and the second cooling channel again to cool and shape the shell, and the mold is opened to take out the finished shell.

[0016] The beneficial effects of the present invention are: 1. The rear mold is heated by the first heating module inside the rear mold. Heating the rear mold before the first injection molding can, on the one hand, eliminate cold mold stress, avoid rapid solidification of the material when it contacts the low-temperature mold, resulting in insufficient filling, and avoid problems such as flow marks, obvious weld lines, and uneven gloss caused by the cold mold. It can also balance the shrinkage rate, and the uniform mold temperature can also reduce the risk of product warping and deformation. On the other hand, by heating the rear mold, the water in the water-based mold release agent can be quickly evaporated before the mold is closed, leaving only the effective ingredients in the water-based mold release agent adhering to the inner wall of the rear mold cavity, preventing the water-based mold release agent from flowing to the joint surface of the first and second injection moldings due to material extrusion during the injection molding process. After being heated by the first heating module, the water-based mold release agent forms a thin film on the inner wall of the rear mold cavity, which can be quickly demolded after injection molding, making the outer surface of the headlight housing smooth. 2. Create a certain angle between the ball valve channel and the ejector pin's extension direction. In this case, the ejector pin extends rapidly from the through-hole to push out the headlight housing from the rear mold cavity. As a result, the ejector pin extends rapidly from the through-hole, causing the nozzle to tilt from a straight position during this process. The nozzle is briefly open and sprays the inner wall of the cavity for a short period of time. Then, as the ejector pin slowly returns to its original position, the nozzle is squeezed and becomes straight from a tilted position. This process not only allows the nozzle to spray release agent, but also allows the nozzle to swing and spray from the inside of the cavity to the outside as the ejector pin retracts, achieving full coverage. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] To facilitate understanding by those skilled in the art, the present invention is further described below with reference to the accompanying drawings.

[0018] Figure 1 This is a schematic structural diagram of the ejector pin retraction of the present invention; Figure 2 This is a schematic structural diagram of the ejector pin of the present invention extending out; Figure 3 for Figure 1 A magnified schematic diagram of point A in the middle; Figure 4 for Figure 2 A magnified schematic diagram of point B in the middle; Figure 5 This is a structural schematic diagram of the valve of the present invention in an open state; Explanation of the accompanying symbols: 1. rear mold; 2. front mold; 3. cavity; 4. ejector; 5. ejector plate; 6. first heating module; 7. second heating module; 8. injection molding runner; 9. water pipe; 10. valve; 11. nozzle. DETAILED DESCRIPTION

[0019] In order to further illustrate the technical means and effects adopted by the present invention to achieve the predetermined purpose of the invention, the specific implementation methods, structures, features and effects of the present invention are described in detail below in conjunction with the accompanying drawings and preferred embodiments.

[0020] like Figure 1-5 As shown, an integrated injection molding and polishing mold for a headlight housing of the present invention comprises a front mold 2, a rear mold 1 and a heating module. A cavity 3 is formed in the rear mold 1. A spraying module is telescopically arranged in the cavity 3. The spraying module is used to spray a release agent onto the inner wall of the cavity 3. The heating module is arranged in the rear mold 1. The heating module preheats the rear film and evaporates the moisture of the release agent sprayed on the inner wall of the cavity 3. In order to ensure the smoothness of the outer surface of the headlight housing after injection molding, it is necessary to avoid adhesion between the material and the mold cavity 3 during injection molding. However, in the existing technology, the release agent is automatically sprayed manually and then injection molding is performed. The injected release agent may be squeezed and pushed and remain on the fitting surface of the two injection molding materials, forming an "isolation layer", resulting in the second injection molding material being unable to form a good bond with the first injection molding material, and then defects such as poor bonding, delamination, and peeling occur, affecting the long-term reliability of the product. To avoid this problem, a water-based release agent is sprayed onto the inner wall of the cavity 3 of the rear mold 1. The rear mold 1 is then heated by a first heating module 6 within the rear mold 1. This heating eliminates cold mold stress, preventing rapid solidification of the material upon contact with the cold mold, which can lead to insufficient filling. It also prevents flow marks, noticeable weld lines, and uneven gloss caused by the cold mold. It also balances shrinkage, and the uniform mold temperature reduces the risk of product warpage. Furthermore, heating the rear mold 1 allows the water in the water-based release agent to evaporate quickly before closing the mold, leaving only the active ingredients adhering to the inner wall of the cavity 3 of the rear mold 1. This prevents the water-based release agent from flowing to the interface between the first and second injection moldings due to material compression during the injection molding process. After being heated by the first heating module 6, the water-based release agent forms a thin film on the inner wall of the cavity 3 of the rear mold 1, enabling rapid demolding after injection, resulting in a smooth outer surface for the headlight housing.

[0021] Water-based release agents are chosen because they use water as a solvent or carrier and contain active release ingredients (such as waxes, silicone oils, polymers, etc.), surfactants, stabilizers, and other additives. After application, the water evaporates, leaving behind a uniform release film. Oil-based release agents, on the other hand, use mineral or synthetic oils as carriers and do not contain water. After application, the oil does not evaporate but remains attached to the mold surface, requiring lengthy cleaning after each use before the next injection molding cycle can begin.

[0022] Because in the prior art, when spraying a water-based release agent, the mold is generally removed, and then the mold cavity 3 is sprayed, or the mold cavity 3 is sprayed from the outside when the mold is opened by a spraying device. However, this spraying method will result in uneven spraying, and this spraying method also increases the number of operating steps, resulting in low production efficiency. In order to avoid this problem, in one embodiment, a flip assembly and an ejector module 4 are also included, the rear mold 1 is slidably set on the flip assembly, the ejector module 4 is set on the flip assembly, the ejector 4 module includes an ejector plate 5 and a plurality of ejectors 4 connected to the ejector plate 5, and the plurality of ejectors 4 pass through the through holes on the rear mold 1 and lead to the cavity 3. The spraying module is set on the front side wall of the ejector 4, and the spraying module sprays the release agent on the inner wall of the cavity 3 as the ejector 4 retracts into the through hole; The ejector pin 4 module is used to push the headlight housing after the final injection molding is completed, so that the headlight housing falls off the rear mold 1. Therefore, the ejector pin 4 needs to be slidably set in the through-hole that runs through the rear mold 1, and the spray module is set on the front side wall of the ejector pin 4. During the injection molding process, the end of the ejector pin 4 forms a complete plane with the inner wall of the cavity 3 of the rear mold 1. After the injection molding is completed, the ejector pin 4 is pushed outward to separate the finished headlight housing from the rear mold 1, and the spray module is extended outside the through-hole. At this time, the spray module is still in the closed state. Then, in preparation for the next injection molding, the ejector pin 4 needs to be fully retracted. As the ejector pin 4 retracts into the through-hole, the edge of the through-hole squeezes the spray module, causing the spray module to change from a closed state to an open state under pressure, and evenly spray a water-based mold release agent onto the inner wall of the cavity 3. As the ejector pin 4 is fully retracted into the through-hole, the spray module is re-sealed by the inner wall of the through-hole. Therefore, by setting the spray module on the front end side wall of the ejector pin 4 module and spraying the water-based release agent onto the inner wall of the cavity 3 according to the movement of the ejector pin 4 module, it can save operation steps and improve work efficiency. Compared with the method of spraying from the outside, spraying from the inner wall of the cavity 3 can also ensure more uniformity and avoid excessive or insufficient spraying in some areas.

[0023] Specifically, the spraying module includes several nozzles 11 and a release agent tank. Several nozzles 11 are arranged on the front end side wall of the ejector 4, and the release agent tank is arranged outside the cavity 3. The nozzle 11 is connected to the release agent tank through a water pipe 9. The ejector 4 retracts into the through hole and squeezes the nozzle 11 to spray the release agent onto the inner wall of the cavity 3. The water pipe 9 is arranged in the ejector 4 and extends along the ejector 4 to the outside of the rear mold 1, and is connected to the external release agent pipe. The release agent pipe is filled with a water-based release agent. In order to spray the release agent onto the inner wall of the cavity 3 of the rear mold 1 when the ejector 4 is retracted, a small water pump is connected to the end of the water pipe 9 in the release agent pipe, which is used to extract the water-based release agent in the release agent pipe and continuously provide pressure to the nozzle 11, so that the release agent is sprayed out in time when the nozzle 11 is in the open state. Because ejector pin 4 is located at the center of cavity 3, multiple nozzles 11 are required to uniformly spray all areas of the inner wall of cavity 3. These nozzles 11 surround the front circumference of ejector pin 4 and are arranged at equal angles. Each nozzle 11 can spray an area within a certain angle, and the combination of multiple nozzles 11 achieves full coverage of the inner wall of cavity 3.

[0024] Since the inner wall of the cavity 3 has a certain depth, if the nozzle 11 is only used to spray briefly at the moment when the ejector pin 4 retracts, the nozzle 11 will only spray a section of the inner wall of the cavity 3 instead of spraying it completely. Moreover, if the cavity 3 of the rear mold 1 is deep, the nozzle 11 can only spray at the moment when it retracts into the through hole, resulting in the area far away from one end of the through hole not being covered. In order to avoid this problem, it is necessary to make the nozzle 11 swing back and forth to expand the spraying range. Therefore, in one embodiment, In the figure, a groove is provided on the side wall of the front end of the ejector pin 4, a spring is provided on the back of the nozzle 11 near the front end of the ejector pin 4 and connected to the groove, and the nozzle 11 is hinged to the edge of the groove on the side away from the front end of the ejector pin 4. A valve 10 is provided at the hinged position of the nozzle 11, and the valve stem on the valve 10 is connected to the outside of the nozzle 11 and fixed in the ejector pin 4. The valve 10 channel forms an angle with the extension direction of the ejector pin 4, so that the valve 10 is closed when the nozzle 11 is fully tilted and completely parallel to the ejector pin 4, and the valve 10 is opened when the nozzle 11 is pressurized and rotates into the groove; When the ejector pin 4 is in the through hole, the nozzle 11 is squeezed into the groove and is parallel to the ejector pin 4. At this time, the spring between the groove and the nozzle 11 is compressed. When the ejector pin 4 pushes out the injection-molded headlight housing, the nozzle 11 is also pushed out. Since the force of the inner wall of the through hole on the nozzle 11 is lost, the nozzle 11 is tilted upward under the action of the spring and forms a certain bending angle. In this state, the nozzle 11 is in a closed state and cannot spray the release agent. This is to avoid the nozzle 11 being in a state of spraying the release agent when the ejector pin 4 needs to be exposed for a long time. Therefore, the structure of the nozzle 11 is designed so that the nozzle 11 can spray the release agent only when it is compressed back.

[0025] Specifically, the nozzle 11 is hinged to the edge of the groove away from the end of the ejector pin 4, allowing the nozzle 11 to rotate about the hinge point. A valve 10, which can be a ball valve, is located at the hinge point. The valve stem of the ball valve is fixed to the side wall of the groove on the ejector pin 4, preventing the valve stem and the ejector pin 4 from relative movement. At this time, the movement of the nozzle 11 itself can change the valve 10 from the closed state to the open state. To prevent the nozzle 11 from continuously spraying release agent when it extends from the through hole, the ball valve is closed when the nozzle 11 is completely straight and also when the nozzle 11 is fully tilted. It is only open when the nozzle 11 is between the fully tilted and completely straight states. To achieve this effect, it is necessary to form a certain angle between the passage of the ball valve and the extension direction of the ejector pin 4. In this case, since the ejector pin 4 extends out of the through hole quickly, it is able to push out the headlight housing on the cavity 3 of the rear mold 1. Therefore, the ejector pin 4 extends out of the through hole at a relatively fast speed, and the nozzle head 11 changes from being straight to being tilted during this process. The nozzle head 11 is in a short open state and completes a short first spraying on the inner wall of the cavity 3. Then, as the ejector pin 4 slowly returns to its original position, as the nozzle head 11 is squeezed and changes from being tilted to being straight, this process not only enables the nozzle head 11 to spray the release agent, but also as the ejector pin 4 retracts, the nozzle head 11 swings and sprays, that is, sprays from the inside to the outside of the cavity 3, thereby achieving full coverage of the spraying.

[0026] Since two-shot molding requires two separate injections of two different colors and materials, and the injection temperatures of the two different materials are also different, to ensure that the two materials can bond together and maintain a certain strength after injection, the temperature of the first injection is generally required to be higher than that of the second injection. Therefore, in order to control the temperature inside the mold cavity 3 during the two injections to reach the required injection temperature and to enable rapid cooling after injection so that the headlight housing inside is cooled and formed, in one embodiment, a cooling module is also included. The cooling module includes a first cooling channel and a second cooling channel respectively provided on the front mold 2 and the rear mold 1. The first cooling channel and the second cooling channel are both connected to a cooling water tank and are respectively connected to a water pump. The water pump is electrically connected to a control module, which controls the start and stop of the water pump to achieve mold temperature control. Temperature sensors are also provided on the front mold 2 and the rear mold 1 and are electrically connected to the control module for control.

[0027] Furthermore, the front mold 2 and the rear mold 1 are provided with two groups of cavities 3, and there are two groups of ejector pin 4 modules corresponding to the two groups of cavities 3 respectively, and the two groups of ejector pin 4 modules are connected to the flip assembly; since two-color injection molding is to be achieved, two cavities 3 are required on the mold of the injection molding machine. After the first injection is completed in one of the rear mold 1 cavities 3 and the first front mold 2, the mold is flipped so that the rear mold 1 cavity 3 after the first injection and the semi-finished product inside it are combined with the second front mold 2, and then the second injection is carried out. Therefore, the mold needs to be flipped by the flip assembly.

[0028] Furthermore, a first hydraulic cylinder and a second hydraulic cylinder are respectively installed between the two sets of ejector pin modules (4) and the flip assembly to push the ejector pins (4) in the through-holes to extend and retract. The ejector pin modules (4) only need to push the finished headlight housing after two injection moldings, while semi-finished products after only one injection molding do not require pushing. Therefore, the two sets of ejector pin modules (4) in the two mold cavities (3) cannot be activated synchronously and must be operated separately. The first and second hydraulic cylinders are the actuating sources for the two ejector pin modules (4).

[0029] Furthermore, a second heating module 7 is included, which is disposed within the front mold 2 and is used to heat the injection molding runner 8 within the front mold 2 and maintain the material in a molten state. The front mold 2 is provided with an injection molding runner 8, which is used to perform injection molding into the mold cavity 3. Due to the presence of the injection molding runner 8 within the front mold 2, if the front mold 2 is not continuously heated, the material within the injection molding runner 8 of the front mold 2 will solidify, causing the injection molding runner 8 to become clogged. Therefore, the front mold 2 needs to be continuously heated during the injection molding process to ensure that the material within the injection molding runner 8 remains molten.

[0030] A variable temperature injection molding process for an integrated lamp housing includes the following steps: S1: Separate the front mold 2 and the rear mold 1 of the injection molding machine; S2: When the ejector pin 4 retracts, the extruder 11 sprays a water-based release agent onto the inner wall of the cavity 3 of the rear mold 1 of the injection molding machine; S3: The rear mold 1 is heated to 80-120°C by the first heating module 6 to evaporate the water of the water-based release agent adhering to the inner wall of the cavity 3 of the rear mold 1 and preheat the mold for 30-60 seconds; S4: After the water evaporates and the effective components of the water-based release agent adhere to the inner wall of the cavity 3 of the rear mold 1, coolant is injected into the first cooling channel and the second cooling channel to cool the front mold 2 and the rear mold 1 to the injection temperature; S5: closing the mold and performing the first injection molding. After the first injection molding is completed, the front mold 2 and the rear mold 1 are separated and the rear mold 1 is flipped through the flip assembly; S6: Clean the fitting surface between the shell and the rear mold 1, close the mold and perform the second injection molding; S7: Cooling liquid is injected into the first cooling channel and the second cooling channel again to cool and shape the shell, and the mold is opened to take out the finished shell.

[0031] The above description is merely a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Although the present invention has been disclosed as above in terms of a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art can, without departing from the scope of the technical solution of the present invention, make some changes or modifications to equivalent embodiments using the technical contents disclosed above. However, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. An integrated injection molding and polishing mold for a headlight housing, characterized by: It includes a front mold, a rear mold and a first heating module. A cavity is formed in the rear mold. A spray module is telescopically arranged in the cavity. The spray module is used to spray a release agent onto the inner wall of the cavity. The first heating module is arranged in the rear mold. The first heating module preheats the rear film and evaporates the moisture of the release agent sprayed on the inner wall of the cavity.

2. The integrated injection molding and polishing mold for a vehicle lamp housing according to claim 1, characterized in that: The mold further includes a flip assembly and an ejector module. The rear mold is slidably arranged on the flip assembly. The ejector module is arranged on the flip assembly. The ejector module includes an ejector plate and a plurality of ejectors connected to the ejector plate. The plurality of ejectors pass through the through holes on the rear mold and lead into the mold cavity. The spray module is arranged on the front end side wall of the ejector. As the ejector retracts into the through hole, the spray module sprays a release agent onto the inner wall of the mold cavity.

3. The integrated injection molding and polishing mold for a vehicle lamp housing according to claim 2, characterized in that: The spraying module includes several nozzles and a release agent tank. The several nozzles are arranged on the front end side wall of the ejector pin. The release agent tank is arranged outside the mold cavity. The nozzles and the release agent tank are connected through a water pipe. The ejector pin retracts into the through hole and squeezes the nozzle to spray the release agent onto the inner wall of the mold cavity.

4. The integrated injection molding and polishing mold for a vehicle lamp housing according to claim 3, characterized in that: A groove is provided on the side wall of the front end of the ejector pin, a spring is provided on the back side of the nozzle close to the front end of the ejector pin and connected to the groove, the nozzle is hinged to the edge of the groove on the side away from the front end of the ejector pin, a valve is provided at the hinged position of the nozzle, the valve stem on the valve is connected to the outside of the nozzle and fixed in the ejector pin, the valve channel forms an angle with the extension direction of the ejector pin, so that the valve is closed when the nozzle is fully tilted and completely parallel to the ejector pin, and the valve is opened when the nozzle is pressurized and rotates into the groove.

5. The integrated injection molding and polishing mold for a vehicle lamp housing according to claim 1, characterized in that: It also includes a cooling module, which includes a first cooling channel and a second cooling channel respectively arranged on the front mold and the rear mold, and the first cooling channel and the second cooling channel are both connected to a cooling water tank.

6. The integrated injection molding and polishing mold for a vehicle lamp housing according to claim 3, characterized in that: The front mold and the rear mold are provided with two groups of cavities, and the ejector modules are provided with two groups corresponding to the two groups of cavities respectively.

7. The integrated injection molding and polishing mold for a vehicle lamp housing according to claim 6, characterized in that: A first hydraulic cylinder and a second hydraulic cylinder are respectively provided between the two groups of ejector modules and the flip assembly for pushing the ejector in the through hole to extend and retract.

8. The integrated injection molding and polishing mold for a vehicle lamp housing according to claim 2, characterized in that: It also includes a second heating module, which is arranged in the front mold and is used to heat the injection channel in the front mold and keep the material in a molten state.

9. The integrated injection molding and polishing mold for a vehicle lamp housing according to claim 1, characterized in that: The front mold is provided with an injection flow channel.

10. A variable temperature molding process for integrated injection molding of a vehicle lamp housing, applicable to an integrated injection molding and polishing mold for a vehicle lamp housing as claimed in any one of claims 1 to 9, characterized in that: The following steps are involved: S1: Separate the front mold and the rear mold of the injection molding machine; S2: Spraying a water-based release agent onto the inner wall of the rear mold cavity of the injection molding machine through the extrusion nozzle when the ejector pin retracts; S3: The rear mold is heated to 80-120°C by the first heating module to evaporate the water of the water-based release agent adhering to the inner wall of the rear mold cavity and preheat the mold for 30-60 seconds; S4: After the water evaporates and the effective components of the water-based release agent adhere to the inner wall of the rear mold cavity, coolant is injected into the first cooling channel and the second cooling channel to cool the front mold and the rear mold to the injection temperature; S5: close the mold and perform the first injection. After the first injection is completed, separate the front mold and the rear mold and flip the rear mold through the flip assembly; S6: Clean the fitting surface between the shell and the rear mold, close the mold and perform the second injection molding; S7: Cooling liquid is injected into the first cooling channel and the second cooling channel again to cool and shape the shell, and the mold is opened to take out the finished shell.

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