Molding process of plastic clamshell type cavity structure internally provided with flow guide partition

Abstract

The invention relates to a forming process of a plastic clamshell type cavity structure internally provided with a flow guide partition, according to the scheme, firstly, preforming of two shells is completed by means of a preforming mold and two injection molding half molds, the main body structure of the shell in the preforming stage is cooled and shaped, but a to-be-welded area is still in a high-temperature and weldable state; opening the two injection molding half molds, and moving out the pre-forming mold; the left half mold and the right half mold are subjected to secondary mold closing, the shells in the two half molds make contact with each other and are extruded with the help of mold closing force, and finally welding is achieved; by means of the inlet and outlet positions of the product, the mold can introduce pressurized air into the cavity, and cooling and shaping of the product are further enhanced; and finally forming the product and taking the product.

Description

Technical Field

[0001] The invention relates to a molding process, in particular to a molding process of a plastic clamshell cavity structure with an internal flow guide partition, which belongs to the extension and expansion of the injection molding processing technology field. Background Art

[0002] Parts with a plastic clamshell cavity structure with internal flow-guiding partitions are a common type of parts in the injection molding field. Such parts are usually welded together from two separate parts on the left and right to form a hollow cavity structure with a flow-guiding partition, such as common oil-gas separation parts, oil-liquid separation parts, etc.; if there are no strict sealing requirements between the flow-guiding partitions, a physical partition with concave and convex fit can be used; if there are sealing requirements between the flow-guiding partitions, welding technology is generally used. In traditional technology, similar clamshell parts are usually completed by injection molding and then heating and welding. In terms of hardware, two sets of injection molding and welding equipment are required, and in terms of the process, the two sets of injection molding and welding processes need to be coordinated and completed, combined with many uncontrollable factors such as the logistics transfer of parts. Therefore, its production cycle is long, the equipment investment is large, and there are many uncontrollable factors in the manufacturing process, so the product quality control is relatively difficult. Because hot melt welding has high requirements for the process, usually there are strict requirements for welding time, welding temperature, welding pressure, ambient temperature and other conditions. A slight change in the process conditions can easily cause local cold welding, resulting in the risk of leakage, and the defect is not easy to detect after it occurs. Therefore, a new solution is urgently needed to solve the above technical problems. Summary of the invention

[0003] The present invention aims at the problems existing in the prior art and provides a molding process for a plastic clamshell cavity structure with an internal flow guide partition. This technical solution solves the current problem of cold welds in clamshell parts and improves production efficiency. It efficiently integrates the injection molding and welding processes, allowing welding to be completed directly in the injection molding process, simplifying the process flow and further ensuring product quality.

[0004] In order to achieve the above object, the technical solution of the present invention is as follows: a molding process of a plastic clamshell cavity structure with an internal flow guide partition, the process comprising the following steps:

[0005] Step 1: The left and right mold halves are in a separated open state, and the preforming mold is initially set outside the mold movement range; Step 2: The preforming mold is moved between the left and right mold halves through the moving platform;

[0006] Step 3: The left and right mold halves move relative to each other and clamp the middle mold to complete a mold closing. The contours on both sides of the preforming mold are consistent with the contours of the parting surfaces of the left and right mold halves, and two independent sealed cavities are formed.

[0007] Step 4: The head of the injection molding machine injects molten rubber into the main gate of the preform mold. Under the action of injection pressure, the rubber is distributed by a specially designed flow channel and injected into the left and right sealed cavities at the same time. The size and direction of the flow channel should be designed according to the size, weight and structural characteristics of the shells on both sides;

[0008] Step 5: After the injection is completed, the nozzle and the main gate of the preforming mold are separated. After a certain period of cooling and holding pressure, the left and right half molds preform two half shells. The cooling and holding time will be adjusted according to different products.

[0009] Step 6: The left and right mold halves are opened, and the preform mold moves out of the mold movement range. At this time, the shells in the two half molds still remain in their respective molds. By controlling the temperature of the mold and the middle mold, the main structure of the shell has been basically cooled and shaped, but the area to be welded is in a high-temperature weldable state;

[0010] Step 7: After removing the preform mold, the left and right mold halves are clamped for the second time. The shells in the left and right mold halves are contacted and squeezed under the clamping force of the mold, and finally melted into one. At the same time, with the help of the product's own inlet and outlet positions, the mold will introduce pressurized air into the cavity to further strengthen the cooling and shaping of the product.

[0011] Step 8: After a certain period of cooling and holding pressure, the product is completely cooled and shaped. The cooling and holding pressure time will be adjusted according to different products;

[0012] Step 9: The mold is opened and the product is taken out.

[0013] As an improvement of the present invention, an infrared heating device is provided on the outer side of the preforming mold in step 1, and the infrared heating device and the preforming mold are fixed together, or the infrared heating device is provided in an independently moving device. In step 6, after the mold is opened for the first time, the preforming mold moves out of the movement range of the mold. At the same time, the infrared heating device on the outer side of the preforming mold will be synchronously moved between the two half molds, and auxiliary heating will be performed on the area to be welded of the shell in the two half molds. By controlling the temperature and heating time of the mold and the infrared heating device, the area to be welded of the two half shells is in a high-temperature weldable state.

[0014] As an improvement of the present invention, the moving platform is located between the two half molds and arranged in a cross shape with the mold opening direction of the injection molding machine, preferably in a spatial cross vertically intersecting. The moving platform is installed on a fixed base and can move under program control.

[0015] As an improvement of the present invention, the preforming mold is installed on a mobile platform, and the preforming mold can be moved in and out between the left and right half molds according to a set program under the drive of the mobile platform.

[0016] As an improvement of the present invention, the contours on both sides of the preforming mold respectively match the parting lines of the corresponding half molds, and can form a sealed injection molding space with the corresponding half molds.

[0017] As an improvement of the present invention, the preforming mold is provided with a main gate and a bifurcated flow channel. The main gate can be provided at the top of the preforming mold, which is conducive to the injection and distribution of the rubber material. The size and trend of the bifurcated flow channel should be designed according to the size, weight and structural characteristics of the shells on both sides. After the preforming mold and the left and right half molds are closed, the rubber material entering from the main gate can enter the left and right half molds respectively through the bifurcated flow channel.

[0018] As an improvement of the present invention, a temperature control system is provided inside the preforming mold, and specifically, a hot runner system commonly used in the industry can be used to ensure that the rubber in the runner will not cool down during the working time. At the same time, a separate mold temperature control is performed for the area to be welded on the preforming mold, and specifically, a separate water channel can be set on the mold, and a mold temperature controller can be used for effective control.

[0019] As an improvement of the present invention, according to different product characteristics, the left and right injection mold halves include a temperature control system, which can be specifically achieved by locally setting up separate water channels and controlling the medium temperature in the water channels through a mold temperature controller.

[0020] Compared with the prior art, the advantages of the present invention are as follows: the present invention can simultaneously complete the injection molding and welding of the two side shells on one injection molding device, and its key process parameters such as welding temperature, pressure, time, etc. are controlled by the injection molding machine and the mold, and its parameters are relatively more controllable, the manufacturing process is shorter, and it is not easily disturbed by external uncontrollable factors, which effectively solves the defects of traditional processes that easily cause cold welding and improves the bonding quality of the joint position. In addition, the traditional process adopts a process of first injection molding, cooling and shaping, and then heating and welding, while the temperature of the shell in the welding stage of the present invention is guaranteed by the residual temperature of the product, so it is also more energy-saving and environmentally friendly; the process method of the present invention is particularly suitable for replacing the traditional welding process of the plastic clamshell cavity structure with an internal guide partition. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 Schematic diagram of the initial state of the production process;

[0022] Figure 2 It is a schematic diagram of the state where the preforming mold is moved between the two half molds;

[0023] Figure 3 The two half molds move relative to each other and clamp the preforming mold, i.e., a schematic diagram of the first mold closing state;

[0024] Figure 4 Schematic diagram of the state of completing shaping of the two shells and removing them from the preforming mold;

[0025] Figure 5 It is a schematic diagram of the secondary mold closing state of two half molds;

[0026] Figure 6 This is a schematic diagram of the secondary mold opening and product removal status;

[0027] Figure 7 is a schematic diagram of the flow channel structure;

[0028] Figure 8 —15 is a schematic diagram of the entire production process in which an infrared heating device is provided on the outer side of the preforming mold.

[0029] In the figure: 1. machine head, 2. left mold half, 3. right mold half, 4. preforming mold, 5. nozzle, 6. main gate, 7. pressure gas inlet, 8. pressure gas inlet, 9. moving platform, 10. plastic clamshell cavity, 11. runner. DETAILED DESCRIPTION

[0030] In order to deepen the understanding of the present invention, the present embodiment is described in detail below with reference to the accompanying drawings.

[0031] Example 1: See Figure 1 — Figure 7 , a molding process of a plastic clamshell cavity structure with an internal flow guide partition, the process comprising the following steps:

[0032] Step 1: See Figure 1 , the left mold half 2 and the right mold half 3 are in a separated open state, and the preforming mold 4 is initially arranged outside the mold movement trajectory;

[0033] Step 2: See Figure 2 , the preforming mold 4 is moved between the left and right mold halves by the moving platform 9;

[0034] Step 3: See Figure 3 , the left and right mold halves move relative to each other and clamp the middle mold, i.e., the preforming mold 4, to complete the first mold closing. In this scheme, the contours on both sides of the preforming mold 4 are consistent with the contours of the parting surfaces of the left and right mold halves, and two independent sealed cavities are formed;

[0035] Step 4: During the first mold closing process, the head 1 of the injection molding machine simultaneously injects molten rubber into the main gate 6 of the preform mold. Under the action of the injection pressure, the rubber is distributed by the specially designed flow channel 11 and injected into the left and right sealed cavities at the same time. The size and direction of the flow channel should be designed according to the size, weight and structural characteristics of the shells on both sides;

[0036] Step 5: After the injection is completed, the nozzle 5 and the main gate 6 of the preforming mold are separated. After a certain period of cooling and holding pressure, the left and right half molds preform two half shells. The cooling and holding pressure time will be adjusted according to different products.

[0037] Step 6: See Figure 4 , the left and right half molds are opened, and the preforming mold 4 is moved out of the mold. At this time, the shells in the two half molds still stay in their respective molds. By controlling the temperature of the mold and the middle preforming mold, the main structure of the shell has been basically finalized, but the area to be welded is in a high-temperature weldable state;

[0038] Step 7: See Figure 5 After removing the preforming mold 4, the left and right mold halves are clamped for the second time. The shells in the left and right mold halves are contacted and squeezed under the clamping force of the mold and finally melted into one. At the same time, with the help of the product's own inlet and outlet positions, the mold introduces pressurized air into the cavity through the pressure gas inlet 1 to further strengthen the cooling and shaping of the product.

[0039] Step 8: See Figure 6 After a certain period of cooling and holding pressure, the product is completely cooled and shaped. The cooling and holding pressure time will be adjusted according to different products.

[0040] Step 9: The left and right mold halves are opened, the product is formed, and the product is taken out.

[0041] Example 2: See Figure 8 — Fig.15 , a molding process of a plastic clamshell cavity structure with an internal flow guide partition, the process comprising the following steps:

[0042] Step 1: See Figure 8 , the left mold half 2 and the right mold half 3 are in a separated open state, and the preforming mold 4 is initially arranged outside the mold movement track; in this solution, an infrared heating device is arranged outside the preforming mold 4, which can move synchronously with the preforming mold. As an equivalent alternative, the infrared heating device can also be a set of independently movable devices.

[0043] Step 2: See Fig. 9 , the preforming mold 4 is moved between the left and right mold halves by the moving platform 9;

[0044] Step 3: See Fig.10 , the left and right mold halves move relative to each other and clamp the middle mold, i.e., the preforming mold 4, to complete the first mold closing. In this scheme, the contours on both sides of the preforming mold 4 are consistent with the contours of the parting surfaces of the left and right mold halves, and two independent sealed cavities are formed;

[0045] Step 4: During the first mold closing process, the head 1 of the injection molding machine simultaneously injects molten rubber into the main gate 6 of the preform mold. Under the action of the injection pressure, the rubber is distributed by the specially designed flow channel 11 and injected into the left and right sealed cavities at the same time. The size and direction of the flow channel should be designed according to the size, weight and structural characteristics of the shells on both sides;

[0046] Step 5: After the injection is completed, the nozzle 5 and the main gate 6 of the preforming mold are separated. After a certain period of cooling and holding pressure, the left and right half molds preform two half shells. The cooling and holding pressure time will be adjusted according to different products.

[0047] Step 6: See Fig.11 , Fig.12 , the left and right half molds are opened, and the preforming mold 4 is moved out of the mold. At this time, the shells in the two half molds still stay in their respective molds, and the preforming mold moves out of the movement range of the mold. At the same time, the infrared heating device on the outside of the preforming mold will be synchronously moved between the two half molds, and the shells in the two half molds will be auxiliary heated. By controlling the temperature and heating time of the infrared heating device of the mold and the preforming mold temperature, the two half shells The area to be welded is in a high-temperature weldable state;

[0048] Step 7: See Fig.14 After removing the preforming mold 4, the left and right mold halves are clamped for the second time. The shells in the left and right mold halves are contacted and squeezed under the clamping force of the mold and finally melted into one. At the same time, with the help of the product's own inlet and outlet positions, the mold introduces pressurized air into the cavity through the pressure gas inlet 1 to further strengthen the cooling and shaping of the product; Step 8: See Fig.15 After a certain period of cooling and holding pressure, the product is completely cooled and shaped. The cooling and holding pressure time will be adjusted according to different products.

[0049] Step 9: The left and right mold halves are opened, the product is formed, and the product is taken out.

[0050] Example 3: See Figure 1 — Figure 7 In the above scheme, the mobile platform is located between the two mold halves and arranged in a cross shape with the mold opening direction of the injection molding machine, preferably in a spatial cross vertically intersecting. The motion platform is mounted on a fixed base and can be moved under program control. The rest of the design is exactly the same as in Example 1 or 2.

[0051] Example 4: See Figure 1 — Figure 7In the above scheme, the preforming mold 4 is installed on the mobile platform 9. Driven by the mobile platform, the preforming mold 4 can move in and out between the left and right half molds according to a set program. The contours on both sides of the preforming mold are respectively consistent with the parting lines of the corresponding half molds, and can form a sealed injection molding space with the corresponding half molds. The rest of the design is exactly the same as that of embodiment 1 or 2.

[0052] Example 5: See Figure 1 — Figure 7 In the above scheme, the preforming mold 4 is provided with a main gate 6 and a bifurcated flow channel 11. The main gate 6 can be provided at the top of the preforming mold, which is conducive to the injection and distribution of the rubber material; the size and trend of the bifurcated flow channel 11 should be designed according to the size, weight and structural characteristics of the shells on both sides. After the preforming mold and the left and right half molds are closed, the rubber material entering from the main gate can enter the left and right half molds respectively through the bifurcated flow channel. The rest of the design is exactly the same as that of embodiment 1 or 2.

[0053] Example 6: See Figure 1 — Figure 7 In the above scheme, a temperature control system is provided inside the preforming mold, and a common hot runner system in the industry can be used to ensure that the rubber in the runner will not cool down during the working time. At the same time, a separate mold temperature control is performed for the area to be welded on the preforming mold, and a separate water channel can be set on the mold, and a mold temperature controller can be used for effective control. The rest of the design is exactly the same as that of Example 1 or 2.

[0054] Example 7: See Figure 1 — Figure 7 In the above scheme, according to different product characteristics, the left and right injection mold halves include a temperature control system, which can be specifically configured by locally setting a separate water channel and controlling the medium temperature in the water channel through a mold temperature controller. The rest of the design is exactly the same as in Example 1 or 2.

[0055] The present invention can also combine at least one of the technical features described in Examples 3, 4, 5, 6, and 7 with Example 1 or 2 to form a new implementation method.

[0056] The present invention can simultaneously complete the injection molding and welding of the two side shells on one injection molding device, and the key process parameters such as welding temperature, pressure, time, etc. are controlled by the injection molding machine and the mold, and the parameters are relatively more controllable, the manufacturing process is shorter, and it is not easily disturbed by uncontrollable factors from the outside, which effectively solves the defect of the traditional process that is easy to cause cold welding and improves the bonding quality of the joint position. In addition, the traditional process adopts the process of first injection molding, cooling and shaping, and then heating and welding, while the temperature of the shell in the welding stage of the present invention is guaranteed by the residual temperature of the product, so it is also more energy-saving and environmentally friendly.

[0057] It should be noted that the above embodiments are not intended to limit the protection scope of the present invention, and equivalent changes or substitutions made on the basis of the above technical solutions all fall within the protection scope of the claims of the present invention.

Claims

1. A molding process of a plastic clamshell cavity structure with an internal flow guide partition, characterized in that: The process comprises the following steps: Step 1: The left and right mold halves are in a separated open state, and the preform mold is initially set outside the mold movement range; Step 2: The preform mold is moved between the two half molds through a mobile platform; Step 3: The left and right half molds move relative to each other and clamp the preforming mold to complete a mold closing. The contours on both sides of the preforming mold are consistent with the contours of the parting surfaces of the left and right half molds, and two independent sealed cavities are formed. Step 4: The nozzle of the injection molding machine injects molten rubber into the main gate of the preform mold. Under the action of injection pressure, the rubber is distributed through the runner and injected into the left and right sealed cavities at the same time; Step 5: After the injection is completed, the nozzle and the main gate of the preforming mold are separated, and after cooling and pressure holding, the left and right half molds preform two half shells; Step 6: The mold is opened, and the preform mold moves out of the moving range of the mold. At this time, the shells in the two half molds still stay in their respective molds. By controlling the temperature of the mold and the preform mold, the main structure of the shell has been cooled and shaped, and the area to be welded is in a high-temperature weldable state; Step 7: After removing the preform mold, the mold is closed for the second time. The shells in the left and right half molds contact and squeeze each other under the mold clamping force, and finally melt into one. At the same time, with the help of the product's own inlet and outlet positions, the mold will introduce compressed air into the cavity to strengthen the cooling and shaping of the product inside. Step 8: After cooling and holding pressure, the product is completely cooled and shaped; Step 9: The mold is opened and the product is taken out.

2. The molding process of the plastic clamshell cavity structure with internal flow guide partition according to claim 1 is characterized in that: In step 1, an infrared heating device is arranged on the outer side of the preforming mold, and the infrared heating device and the preforming mold are fixed together, or the infrared heating device is arranged in an independently moving device. In step 6, after the mold is opened for the first time, the preforming mold moves out of the moving range of the mold. At the same time, the infrared heating device on the outer side of the preforming mold will be synchronously moved between the two half molds, and the area to be welded of the shell in the two half molds will be auxiliary heated. By controlling the temperature and heating time of the mold and the infrared heating device, the area to be welded of the two half shells is in a high-temperature weldable state.

3. The molding process of the plastic clamshell cavity structure with internal flow guide partition according to claim 1 or 2, characterized in that: The mobile platform is located between the two half molds and arranged in a cross shape with the mold opening direction of the injection molding machine. The mobile platform is installed on a fixed base and moves under the control of the program.

4. The molding process of the plastic clamshell cavity structure with internal flow guide partition according to claim 3 is characterized in that: The preforming mold is installed on a mobile platform. Driven by the mobile platform, the preforming mold moves in and out between the left and right half molds according to a set program.

5. The molding process of the plastic clamshell cavity structure with internal flow guide partition according to claim 4 is characterized in that: The contours on both sides of the preforming mold are respectively matched with the parting lines of the corresponding half molds, forming a sealed injection space with the corresponding half molds.

6. The injection molding process of the plastic clamshell cavity structure with internal flow guide partition according to claim 5, characterized in that: The preforming mold is provided with a main gate and a bifurcated flow channel. When the preforming mold and the left and right half molds are closed, the rubber material entering from the main gate enters the left and right half molds respectively through the bifurcated flow channel.

7. The molding process of the plastic clamshell cavity structure with internal flow guide partition according to claim 6 is characterized in that: The interior of the preforming mold is equipped with a temperature control system and a hot runner system is used to ensure that the rubber in the runner will not cool down during the working time.

8. The molding process of the plastic clamshell cavity structure with internal flow guide partition according to claim 1 is characterized in that: A temperature control system is set in the left and right half molds, and a separate water channel is set locally. The temperature of the medium in the water channel is controlled by a mold temperature controller.

9. The molding process of the plastic clamshell cavity structure with internal flow guide partition according to claim 8, characterized in that: The shell of the plastic clamshell cavity structure parts processed by this process has inlets and outlets for fluid to flow in and out. After the mold is closed for the second time, pressurized gas is introduced into the inlet and outlet positions of the shell on both sides to enhance the cooling and shaping inside the shell.

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