Thermal forming die capable of rapidly cooling edges of shaped products

Abstract

A thermal forming die capable of rapidly cooling the edge of a shaped product comprises an upper die and a lower die. The upper die comprises an upper die plate, an upper shearing die and a material pressing ring, the upper shearing die is installed on the upper die plate, the upper shearing die is provided with a cavity, and the material pressing ring is arranged in the cavity of the upper shearing die; the lower die comprises a lower die plate, a lower die body, a lower shearing die and a forming die, the lower die body is installed on the lower die plate and located above the lower die plate, the lower shearing die is installed on the lower die body, and the forming die is installed on the lower die body and located on the inner side of the lower shearing die; the die is characterized in that a first cooling water flow channel is arranged in the material pressing ring, the upper die further comprises a first water inlet pipe and a first water outlet pipe, and the water outlet end of the first water inlet pipe and the water inlet end of the first water outlet pipe are respectively communicated with the first cooling water flow channel. According to the utility model, the edge of a product can be quickly and fully cooled and shaped in the production process, and the product quality can be improved.

Description

Technical Field

[0001] This utility model relates to thermoforming equipment, and more specifically, to a thermoforming mold that can quickly cool and solidify the edges of a product. Background Technology

[0002] An existing thermoforming mold for manufacturing plastic products (such as plastic cups, plastic boxes, plastic lids, etc.) can complete molding and shearing operations. This thermoforming mold includes an upper mold and a lower mold; the upper mold includes an upper template, an upper shearing die, and a pressure ring. The upper shearing die is mounted on the upper template and has a cavity (usually the inner edge of the lower end of the upper shearing die is the upper shearing blade). The pressure ring is located in the cavity of the upper shearing die and can move up and down within the cavity of the upper shearing die; the lower mold includes a lower template, a lower mold body, a lower shearing die, and a forming die. The lower mold body is mounted on and above the lower template, and the lower shearing die is mounted on and above the lower mold body (usually the outer edge of the upper end of the lower shearing die is the lower shearing blade, which matches the upper shearing blade). The forming die is mounted on the lower mold body and is located inside the lower shearing die; the lower end face of the pressure ring matches and corresponds to the upper end face of the lower shearing die.

[0003] When manufacturing plastic products, the plastic sheet is first heated to reach the molding temperature. The heated plastic sheet then passes through the molding area, where the thermoforming mold closes, and the pressure ring presses the plastic sheet firmly onto the lower mold. Through positive or negative pressure thermoforming, the plastic sheet is tightly adhered to the molding mold. After molding, the upper and lower shear blades perform a shearing action, cutting the plastic product out of the molding sheet to obtain an individual plastic product. Next, the plastic product is removed from the molding mold. Finally, air can be blown onto the plastic product to blow it away from the thermoforming mold.

[0004] To shorten the molding cycle, cooling water channels are usually installed on the lower mold to cool the forming mold and the lower shearing mold, allowing the plastic product to cool and solidify. However, when the product edge thickness is large (corresponding to a larger plastic sheet thickness), due to the poor thermal conductivity of plastic, it is difficult to adequately cool the edge of the plastic product near its upper surface if only the forming mold and lower shearing mold are used for indirect cooling. Thus, after the plastic product leaves the forming mold, the edge near its upper surface will cool further. Because the edge of the plastic product is not constrained by external forces during this cooling process, it is more prone to deformation. Significant deformation will result in defective or scrap products. Utility Model Content

[0005] The technical problem this invention aims to solve is to provide a thermoforming mold capable of rapidly cooling and shaping the edges of a product. This thermoforming mold can quickly and fully cool and shape the product edges during production, which is beneficial for improving product quality. The technical solution adopted is as follows:

[0006] A thermoforming mold capable of rapidly cooling and shaping the edges of a product includes an upper mold and a lower mold. The upper mold includes an upper template, an upper shearing die, and a pressure ring. The upper shearing die is mounted on the upper template and has a cavity. The pressure ring is located within the cavity of the upper shearing die. The lower mold includes a lower template, a lower mold body, a lower shearing die, and a forming die. The lower mold body is mounted on and above the lower template. The lower shearing die is mounted on the lower mold body and is located inside the lower shearing die. The lower end face of the pressure ring matches and corresponds to the upper end face of the lower shearing die. The mold is characterized in that the pressure ring has a first cooling water channel, and the upper mold also includes a first water inlet pipe and a first water outlet pipe. The outlet end of the first water inlet pipe and the inlet end of the first water outlet pipe are respectively connected to the first cooling water channel.

[0007] Typically, the lower mold is equipped with a mold cooling water channel to cool the forming mold and the lower shearing mold.

[0008] In the production of plastic products, the plastic sheet is first heated to reach the molding temperature. The heated sheet then passes through the molding area, where the thermoforming mold closes, and the pressure ring presses the sheet firmly against the lower shearing die. Through positive or negative pressure thermoforming, the sheet adheres tightly to the molding die. Subsequently, the mold's cooling water system cools both the molding die and the lower shearing die. Simultaneously, cooling water flows into the first cooling water channel via the first inlet pipe. This water then flows out through the first outlet pipe, cooling the pressure ring as it passes through the channel. This rapid cooling and shaping of the portion of the plastic sheet pressed by the pressure ring (which, after shearing, forms the edge of the product) allows for rapid cooling and shaping. The molded sheet is then sheared by the upper and lower shearing blades, cutting the plastic product out of the sheet. The product is then removed from the molding die. Finally, air is blown onto the product to remove it from the thermoforming mold. Since the edges of the product (i.e., plastic products) are cooled and shaped while being pressed by the pressure ring, it can ensure that the edges of the product are flat after cooling and shaping, which helps to improve product quality and greatly reduce defective or scrap products.

[0009] In the preferred embodiment, the upper mold further includes an upper mold body, which is installed on and below the upper template, and the upper shearing mold is installed on the upper mold body; the upper mold body has a cavity, and the first water inlet pipe and the first water outlet pipe are arranged in the cavity of the upper mold body.

[0010] In the preferred embodiment, the first cooling water channel is C-shaped, extending circumferentially along the pressure ring. Its two ends are an inlet and an outlet, respectively. The outlet of the first inlet pipe is connected to the inlet of the first cooling water channel, and the outlet of the first cooling water channel is connected to the inlet of the first outlet pipe. When cooling of the pressure ring is required, cooling water is introduced into the inlet of the first cooling water channel through the first inlet pipe. The cooling water flows along the C-shaped path in the first cooling water channel, cooling the pressure ring, and then flows out from the outlet of the first cooling water channel, and then out through the first outlet pipe. Using a C-shaped channel extending circumferentially along the pressure ring facilitates smooth cooling water flow and more uniform cooling of all parts of the pressure ring.

[0011] In a more preferred embodiment, the aforementioned pressure ring includes an inner ring body and an outer ring body. The lower end of the outer ring body is provided with an inwardly protruding annular limiting step. The annular end face of the lower end of the inner ring body is in close contact with the upper surface of the annular limiting step. An annular groove is provided on the outer side of the inner ring body. A first water inlet and a first water outlet are provided on the upper end face of the inner ring body. A water-blocking component is provided in the annular groove to separate the annular groove. The water-blocking component is located between the first water inlet and the first water outlet. The inner side of the outer ring body closes the opening of the annular groove, forming a C-shaped first cooling water channel. The first water inlet constitutes the water inlet end of the first cooling water channel, and the first water outlet constitutes the water outlet end of the first cooling water channel. The water-blocking component can be integrally integrated into the inner ring body or the outer ring body, or it can be a component independent of the inner ring body and the outer ring body (for example, a rubber block or a plastic block can be used as the water-blocking component, and the inner ring body and the outer ring body together clamp the rubber block or plastic block). To prevent water leakage, in a further preferred embodiment, the aforementioned pressure ring also includes an upper sealing ring and a lower sealing ring. Both the upper and lower sealing rings are located between the outer side of the inner ring body and the inner side of the outer ring body, and the upper and lower sealing rings are located on the upper and lower sides of the annular groove, respectively.

[0012] In another preferred embodiment, the first cooling water channel is annular, extending circumferentially along the pressure ring. The upper surface of the pressure ring is provided with a first inlet and a first outlet communicating with the first cooling water channel. The first inlet and the first outlet are offset from each other circumferentially (preferably offset by 180 degrees). The first inlet constitutes the inlet end of the first cooling water channel, and the first outlet constitutes the outlet end. In this case, when cooling of the pressure ring is required, cooling water is introduced into the first inlet through the first inlet pipe. The cooling water flows in two paths along an arc-shaped trajectory (e.g., a semi-circular trajectory) in the first cooling water channel to cool the pressure ring. The water then converges at the first outlet and flows out, before exiting through the first outlet pipe.

[0013] In a preferred embodiment, the upper template includes a first cooling water inlet channel and a first cooling water outlet channel. The inlet end of the first cooling water inlet channel and the outlet end of the first cooling water outlet channel are both located on the side or upper surface of the upper template, while the outlet end of the first cooling water inlet channel and the inlet end of the first cooling water outlet channel are both located on the lower surface of the upper template. The outlet end of the first cooling water inlet channel is connected to the inlet end of the first inlet pipe, and the outlet end of the first outlet pipe is connected to the inlet end of the first cooling water outlet channel. The first cooling water inlet channel is used to connect to a cooling water supply device outside the thermoforming mold, and the first cooling water outlet channel is used to discharge the cooling water flowing through the first cooling water channel to the outside of the thermoforming mold. To facilitate the installation of the thermoforming mold, it is preferable that the inlet end of the first cooling water inlet channel and the outlet end of the first cooling water outlet channel are both located on the side of the upper template.

[0014] When the pressure ring presses the plastic sheet onto the lower die, it moves upward a short distance relative to the upper shearing die. When the die opens, the pressure ring moves downward a short distance relative to the upper shearing die. Therefore, the first inlet pipe and the first outlet pipe should not obstruct the movement of the pressure ring relative to the upper shearing die. In a preferred embodiment, the first inlet pipe and the first outlet pipe are made of flexible plastic tubing. In another preferred embodiment, the first inlet pipe and the first outlet pipe are made of telescopic tubing, such as inner and outer sleeves (with a sealed contact between the outer wall of the inner tube and the inner wall of the outer tube), corrugated pipes, etc.

[0015] The aforementioned pressure ring can move up and down within the cavity of the upper shearing die, applying pressure to the plastic sheet to be molded. In one specific embodiment, a compression spring is installed between the pressure ring and the upper die plate. When the compression spring contracts, it allows the pressure ring to apply a certain pressure to the plastic sheet to be molded. In another specific embodiment, a sealing ring is provided on the outside of the pressure ring, forming a pressure chamber between the upper end of the pressure ring and the inner wall of the upper shearing die cavity. Compressed gas can be introduced into the pressure chamber, allowing the pressure ring to apply a certain pressure to the plastic sheet to be molded. In yet another specific embodiment, a compression spring is installed between the pressure ring and the upper die plate, and a sealing ring is provided on the outside of the pressure ring, forming a pressure chamber between the upper end of the pressure ring and the inner wall of the upper shearing die cavity. This combination of compression spring and compressed gas allows the pressure ring to apply a certain pressure to the plastic sheet to be molded.

[0016] In a preferred embodiment, the upper die further includes a stretching head, a stretching rod, a stretching rod mounting plate, and a stretching rod mounting plate lifting control mechanism. The stretching head is connected to the lower end of the stretching rod and is located within the cavity of the pressure ring. The upper end of the stretching rod is connected to the stretching rod mounting plate, which is connected to the stretching rod mounting plate lifting control mechanism. The stretching rod mounting plate lifting control mechanism can be located on the upper die plate; or, if the upper die is fixed to the frame, it can also be located on the frame. The stretching rod mounting plate lifting control mechanism drives the stretching rod to move up and down; driven by the stretching rod, the stretching head can move up and down within the cavity of the pressure ring. The stretching rod mounting plate lifting control mechanism may include a stretching cylinder, with the piston rod of the stretching cylinder connected to the stretching rod mounting plate. The cylinder body of the stretching cylinder can be mounted on the upper die plate; or, if the upper die is fixed to the frame, the cylinder body of the stretching cylinder can also be mounted on the frame.

[0017] Preferably, a tension head limiting sleeve is fitted onto the lower part of the aforementioned tension rod, with the lower end of the tension head limiting sleeve contacting the top surface of the tension head. During the upward movement of the tension rod and tension head, when the upper end of the tension head limiting sleeve contacts the lower surface of the upper template, the tension head stops rising, thus preventing the tension head from impacting the first inlet pipe and the first outlet pipe.

[0018] To ensure smooth movement of the stretching head, it is preferable to have a stretching rod guide sleeve running vertically on the upper template, with the stretching rod positioned within the stretching rod guide sleeve and slidingly engaged with it.

[0019] In a preferred embodiment, the lower mold further includes an ejector rod and an ejector rod mounting plate. The molding die includes a side mold and a movable bottom mold. The side mold is mounted on the lower mold body and located inside the lower shearing die. The movable bottom mold is connected to the upper end of the ejector rod, and the lower end of the ejector rod extends below the lower mold plate and connects to the ejector rod mounting plate. The ejector rod mounting plate can be connected to an ejector rod lifting drive mechanism. The side mold is used to mold the edge portion or sidewall of the plastic product; the movable bottom mold is used to mold the middle portion or bottom of the plastic product. During demolding, the ejector rod rises, ejecting the plastic product.

[0020] In a more preferred embodiment, the ejector rod is provided with a vertically oriented cooling water inlet channel and a vertically oriented cooling water outlet channel. The lower end of the cooling water inlet channel is the inlet end and the upper end is the outlet end, and the upper end of the cooling water outlet channel is the inlet end and the lower end is the outlet end. The movable bottom mold is provided with a second cooling water flow channel. The outlet end of the cooling water inlet channel is connected to the inlet end of the second cooling water flow channel, and the outlet end of the second cooling water flow channel is connected to the inlet end of the cooling water outlet channel. Cooling water is introduced into the second cooling water flow channel through the cooling water inlet channel. After heat exchange with the movable bottom mold, the cooling water is discharged through the cooling water outlet channel, which can cool the movable bottom mold and help the molded sheet cool and solidify quickly.

[0021] In a more preferred embodiment, the lower template is provided with a vertically oriented limiting shaft, and the ejector rod mounting plate is provided with a limiting through hole. The limiting shaft is located within the limiting through hole, and a lower limiting washer is sleeved on the lower end of the limiting shaft, positioned below the ejector rod mounting plate. During the descent of the ejector rod mounting plate, when the lower surface of the ejector rod mounting plate contacts the upper end face of the lower limiting washer, the ejector rod mounting plate stops descending. The lower limiting washer serves as a buffer and can be made of rubber or polyurethane elastomer.

[0022] Typically, the inner edge of the lower end of the upper shearing die is the upper shearing blade; the outer edge of the upper end of the lower shearing die is the lower shearing blade. The lower shearing blade matches the upper shearing blade, so that the thermoforming die can complete the shearing action after completing the forming process, thus obtaining a single plastic product.

[0023] This invention features a first cooling water channel within the pressure ring. After the plastic sheet is formed, cooling water flows through the first cooling water channel while the pressure ring presses the plastic sheet firmly, thus rapidly cooling and shaping the portion of the plastic sheet pressed by the pressure ring (which, after shearing, forms the edge of the product, i.e., the plastic article). The resulting product has a smooth edge, which helps improve product quality. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the structure of a preferred embodiment of the present invention (molded state).

[0025] Figure 2 yes Figure 1 Top view of the medium-pressure material ring cooling water conveying structure;

[0026] Figure 3 yes Figure 1 Schematic diagram of the structure of the medium-pressure material ring;

[0027] Figure 4 yes Figure 3 Top view of the pressure ring shown;

[0028] Figure 5 This is a structural schematic diagram of the preferred embodiment of the present invention in the mold-opening state. Detailed Implementation

[0029] like Figures 1 to 5 As shown, this thermoforming mold, which can quickly cool and shape the edges of the product, includes an upper mold 1 and a lower mold 2.

[0030] The upper mold 1 includes an upper template 11, an upper mold body 12, an upper shearing die 13, a pressure ring 14, a first water inlet pipe 15, and a first water outlet pipe 16. The upper mold body 12 is mounted on the upper template 11 and located below it. The upper shearing die 13 is mounted on the upper mold body 12. The upper shearing die 13 has a cavity, and the pressure ring 14 is disposed within the cavity of the upper shearing die 13. The upper mold body 12 also has a cavity, and the first water inlet pipe 15 and the first water outlet pipe 16 are arranged within the cavity of the upper mold body 12. The pressure ring 14 has a first cooling water channel 141, and the outlet end of the first water inlet pipe 15 and the inlet end of the first water outlet pipe 16 are respectively connected to the first cooling water channel 141.

[0031] In this embodiment, the first cooling water channel 141 is C-shaped, extending circumferentially along the pressure ring 14. Its two ends are an inlet and an outlet, respectively. The outlet of the first inlet pipe 15 is connected to the inlet of the first cooling water channel 141, and the outlet of the first cooling water channel 141 is connected to the inlet of the first outlet pipe 16. When cooling of the pressure ring 14 is required, cooling water is introduced into the inlet of the first cooling water channel 141 through the first inlet pipe 15. The cooling water flows along the C-shaped path in the first cooling water channel 141, cooling the pressure ring 14, and then flows out from the outlet of the first cooling water channel 141, and then out through the first outlet pipe 16. (Reference) Figure 3 and Figure 4 The pressing ring 14 includes an inner ring body 142 and an outer ring body 143. The lower end of the outer ring body 143 is provided with an inwardly protruding annular limiting step 144. The annular end face of the lower end of the inner ring body 142 is in close contact with the upper surface of the annular limiting step 144. An annular groove 145 is provided on the outer side of the inner ring body 142. A first water inlet 146 and a first water outlet 147 are provided on the upper end face of the inner ring body 142. A water-blocking component 148 is provided in the annular groove 145 to separate the annular groove 145. The water-blocking component 148 is located between the first water inlet 146 and the first water outlet 147. The inner side of the outer ring body 143 closes the groove opening of the annular groove 145 to form a C-shaped first cooling water channel 141. The first water inlet 146 constitutes the water inlet end of the first cooling water channel 141, and the first water outlet 147 constitutes the water outlet end of the first cooling water channel 141. The water-proof component 148 can be integrally integrated with the inner ring 142 or the outer ring 143, or it can be a component independent of the inner ring 142 and the outer ring 143. The pressure ring 14 also includes an upper sealing ring 149 and a lower sealing ring 1410. The upper sealing ring 149 and the lower sealing ring 1410 are both located between the outer side of the inner ring 142 and the inner side of the outer ring 143, and the upper sealing ring 149 and the lower sealing ring 1410 are respectively located on the upper and lower sides of the annular groove 145.

[0032] The upper mold plate 11 is provided with a first cooling water inlet channel 113 and a first cooling water outlet channel 114. The inlet end of the first cooling water inlet channel 113 and the outlet end of the first cooling water outlet channel 114 are both located on the side of the upper mold plate 11, while the outlet end of the first cooling water inlet channel 113 and the inlet end of the first cooling water outlet channel 114 are both located on the lower surface of the upper mold plate 11. The outlet end of the first cooling water inlet channel 113 is connected to the inlet end of the first inlet pipe 15, and the outlet end of the first outlet pipe 16 is connected to the inlet end of the first cooling water outlet channel 114. The first cooling water inlet channel 113 is used to connect with a cooling water supply device outside the thermoforming mold, and the first cooling water outlet channel 114 is used to discharge the cooling water flowing through the first cooling water channel 1141 to the outside of the thermoforming mold.

[0033] In this embodiment, both the first water inlet pipe 15 and the first water outlet pipe 16 are made of plastic hoses.

[0034] The upper mold 1 also includes a stretching head 17, a stretching rod 18, a stretching rod mounting plate 19, and a stretching rod mounting plate lifting control mechanism. The stretching head 17 is connected to the lower end of the stretching rod 18 and is located within the cavity of the pressure ring 14. The upper end of the stretching rod 18 is connected to the stretching rod mounting plate 19, and the stretching rod mounting plate 19 is connected to the stretching rod mounting plate lifting control mechanism. The stretching rod mounting plate lifting control mechanism can be located on the upper template 11; when the upper mold is fixed on the frame, the stretching rod mounting plate lifting control mechanism can also be located on the frame. The stretching rod mounting plate lifting control mechanism is used to drive the stretching rod mounting plate 19 and the stretching rod 18 to move up and down; driven by the stretching rod 18, the stretching head 17 can move up and down within the cavity of the upper mold body 12 and the cavity of the upper shearing mold 13. The stretching rod mounting plate lifting control mechanism may include a stretching cylinder, and the stretching rod mounting plate is connected to the piston rod of the stretching cylinder; the cylinder body of the stretching cylinder can be mounted on the upper template; when the upper mold is fixed on the frame, the cylinder body of the stretching cylinder can also be mounted on the frame.

[0035] A tension head limiting sleeve 110 is sleeved on the lower part of the tension rod 18, and the lower end of the tension head limiting sleeve 110 contacts the top surface of the tension head 17. During the upward movement of the tension rod 18 and the tension head 17, when the upper end of the tension head limiting sleeve 110 contacts the lower surface of the upper template 11, the tension head 17 stops rising, which can prevent the tension head 17 from impacting the first water inlet pipe 15 and the first water outlet pipe 16.

[0036] The upper template 11 is provided with a tension rod guide sleeve 111 that runs vertically. The tension rod 18 is located in the tension rod guide sleeve 111 and slides in cooperation with the tension rod guide sleeve 111.

[0037] In this embodiment, a compression spring 112 is installed between the pressing ring 14 and the upper template 11. When the compression spring 112 contracts, it can apply a certain pressure to the plastic sheet to be formed by the pressing ring 14.

[0038] The lower mold 2 includes a lower template 21, a lower mold body 22, a lower shearing mold 23, and a forming mold 24. The lower mold body 22 is installed on the lower template 21 and is located above the lower template 21. The lower shearing mold 23 is installed on the lower mold body 22. The forming mold 24 is installed on the lower mold body 22 and is located inside the lower shearing mold 23. The lower end face of the pressure ring 14 matches the upper end face of the lower shearing mold 23 and their positions are corresponding.

[0039] The forming mold 24 has a forming cavity. The inner edge of the lower end of the upper shearing mold 13 is the upper shearing blade; the outer edge of the upper end of the lower shearing mold 23 is the lower shearing blade, and the lower shearing blade matches the upper shearing blade.

[0040] The lower mold 2 also includes an ejector rod 25 and an ejector rod mounting plate 26. The forming mold 24 includes a side mold 241 and a movable bottom mold 242. The side mold 241 is mounted on the lower mold body 22 and is located inside the lower shearing mold 23. The movable bottom mold 242 is connected to the upper end of the ejector rod 25, and the lower end of the ejector rod 25 extends below the lower mold plate 21 and is connected to the ejector rod mounting plate 26. The ejector rod mounting plate 26 can be connected to an ejector rod lifting drive mechanism. The side mold 241 is used to mold the edge part or side wall of the plastic product; the movable bottom mold 242 is used to mold the middle part or bottom of the plastic product. During demolding, the ejector rod 25 rises and drives the movable bottom mold 242 to rise, ejecting the plastic product.

[0041] The ejector rod 25 has a vertically oriented cooling water inlet channel 27 and a vertically oriented cooling water outlet channel 28. The lower end of the cooling water inlet channel 27 is the water inlet, and the upper end is the water outlet. The upper end of the cooling water outlet channel 28 is the water inlet, and the lower end is the water outlet. The movable bottom mold 242 has a second cooling water flow channel 29. The outlet of the cooling water inlet channel 27 is connected to the inlet of the second cooling water flow channel 29, and the outlet of the second cooling water flow channel 29 is connected to the inlet of the cooling water outlet channel 28. Cooling water is introduced into the second cooling water flow channel 29 through the cooling water inlet channel 27. After heat exchange with the movable bottom mold 242, the cooling water is discharged through the cooling water outlet channel 28, which can cool the movable bottom mold 242 and help the molded sheet cool and solidify quickly.

[0042] The lower mold 2 is provided with a mold cooling water channel to cool the forming mold 24 and the lower shearing mold 23. The mold cooling water channel includes a third cooling water channel 210 to cool the lower shearing mold 23 and a fourth cooling water channel 211 to cool the side mold 241. The mold cooling water channel is a conventional design in thermoforming molds and will not be described in detail here.

[0043] The lower template 21 is provided with an ejector rod guide sleeve 212 that runs vertically. The ejector rod 25 is located in the ejector rod guide sleeve 212 and slides in cooperation with the ejector rod guide sleeve 212.

[0044] The ejector rod mounting plate 26 is provided with a tube guide sleeve 213, and the lower template 21 is provided with a guide post 214 running vertically. The guide post 214 is located in the tube guide sleeve 213. When the ejector rod mounting plate 26 rises and falls relative to the lower template 21, the tube guide sleeve 213 slides along the guide post 214, which can guide the ejector rod mounting plate 26 and the ejector rod 25 to rise and fall more smoothly.

[0045] The lower template 21 is provided with a vertically oriented limiting shaft 215, and the ejector rod mounting plate 26 is provided with a limiting through hole 216. The limiting shaft 215 is located in the limiting through hole 216, and a lower limiting washer 217 is sleeved on the lower end of the limiting shaft 215, located below the ejector rod mounting plate 26. During the descent of the ejector rod mounting plate 26, when the lower surface of the ejector rod mounting plate 26 contacts the upper end surface of the lower limiting washer 217, the ejector rod mounting plate 26 stops descending. The lower limiting washer 217 serves as a buffer and can be made of rubber or polyurethane elastomer.

[0046] The working principle of this thermoforming mold is briefly described below:

[0047] When making plastic products, the plastic sheet is first heated to reach the molding temperature. After the plastic sheet is heated, it passes through the molding area. At this time, the thermoforming mold closes and the compression spring 112 applies a downward pushing force to the pressure ring 14, so that the pressure ring 14 presses the sheet tightly on the upper end face of the lower shearing die 23.

[0048] Next, the tension rod mounting plate lifting control mechanism drives the tension rod mounting plate 19 to descend, and the tension rod mounting plate 19, tension rod 18, and tension head 17 descend together; the tension head 17 pre-stretches the plastic sheet.

[0049] Then, through positive or negative pressure thermoforming, the plastic sheet is pressed tightly against the forming mold to form the plastic sheet; subsequently, the third cooling water channel 210 cools the lower shearing mold 23, the fourth cooling water channel 211 cools the side mold 241, and the second cooling water channel 29 cools the movable bottom mold 242. At the same time, the first water inlet pipe 15 introduces cooling water into the first cooling water channel 141. After flowing through the first cooling water channel 141, the cooling water flows out through the first water outlet pipe 16. When the cooling water flows through the first cooling water channel 141, it cools the pressure ring 14, thus shaping the formed sheet.

[0050] Next, the lower mold 2 rises further, and the lower shearing blade on the outer edge of the upper end of the lower shearing mold 23 cooperates with the upper shearing blade on the inner edge of the lower end of the upper shearing mold 13 to cut the shaped sheet and cut the plastic product out of the shaped sheet to obtain a single plastic product.

[0051] Subsequently, the tension rod mounting plate lifting control mechanism drives the tension rod mounting plate 19, tension rod 18, and tension head 17 to rise together, and the tension head 17 returns to the cavity of the upper shearing die 13.

[0052] Then the lower mold 2 descends, and the edge of the plastic product leaves the pressure ring 14; subsequently, the ejector rod mounting plate 26 and ejector rod 25 rise, and the movable bottom mold 242 rises along with it and ejects the plastic product, thus demolding the plastic product.

[0053] Then, air can be blown onto the plastic product to blow it away from the thermoforming mold, thus completing one thermoforming process. Subsequently, the ejector rod mounting plate 26 and ejector rod 25 descend and drive the movable bottom mold 242 down to the required molding position, preparing for the next thermoforming process.

[0054] In other embodiments, the first cooling water channel may also be annular, extending circumferentially along the pressure ring. The upper surface of the pressure ring is provided with a first inlet and a first outlet communicating with the first cooling water channel. The first inlet and the first outlet are offset from each other circumferentially (preferably offset by 180 degrees). The first inlet constitutes the inlet end of the first cooling water channel, and the first outlet constitutes the outlet end of the first cooling water channel. In this case, when cooling of the pressure ring is required, cooling water is introduced into the first inlet through the first inlet pipe. The cooling water flows in two paths along an arc-shaped trajectory (e.g., a semi-circular trajectory) in the first cooling water channel to cool the pressure ring. The water then converges at the first outlet and flows out, before exiting through the first outlet pipe.

[0055] In other implementation schemes, the first inlet pipe and the first outlet pipe may also be telescopic pipes, such as inner and outer sleeves (with a sealed contact between the outer wall of the inner pipe and the inner wall of the outer pipe), corrugated pipes, etc.

[0056] In other embodiments, a sealing ring can be provided on the outside of the pressure ring, so that the upper end of the pressure ring forms a pressure chamber with the inner wall of the upper shearing die cavity. Compressed gas can be introduced into the pressure chamber, so that the pressure ring can apply a certain pressure to the plastic sheet to be formed; or, a compression spring is installed between the pressure ring and the upper template, and a sealing ring is provided on the outside of the pressure ring, so that the upper end of the pressure ring forms a pressure chamber with the inner wall of the upper shearing die cavity. The combination of compression spring and compressed gas is used to apply a certain pressure to the plastic sheet to be formed by the pressure ring.

Claims

1. A thermoforming mold capable of rapidly cooling and shaping the edges of a product, comprising an upper mold and a lower mold; the upper mold includes an upper template, an upper shearing die, and a pressure ring, the upper shearing die being mounted on the upper template and having a cavity, the pressure ring being disposed within the cavity of the upper shearing die; the lower mold includes a lower template, a lower mold body, a lower shearing die, and a forming die, the lower mold body being mounted on and above the lower template, the lower shearing die being mounted on the lower mold body, and the forming die being mounted on the lower mold body and located inside the lower shearing die; the lower end face of the pressure ring matches and corresponds in position to the upper end face of the lower shearing die, characterized in that: The pressing ring is provided with a first cooling water channel, and the upper mold also includes a first water inlet pipe and a first water outlet pipe. The water outlet end of the first water inlet pipe and the water inlet end of the first water outlet pipe are respectively connected to the first cooling water channel.

2. The thermoforming mold capable of rapidly cooling and shaping the edges of a product according to claim 1, characterized in that: The upper mold also includes an upper mold body, which is installed on and below the upper template. The upper shearing mold is installed on the upper mold body. The upper mold body has a cavity, and the first water inlet pipe and the first water outlet pipe are arranged in the cavity of the upper mold body.

3. The thermoforming mold capable of rapidly cooling and shaping the edges of a product according to claim 1, characterized in that: The first cooling water channel is C-shaped, extending circumferentially along the pressing ring, with an inlet and an outlet at its two ends. The outlet of the first inlet pipe is connected to the inlet of the first cooling water channel, and the outlet of the first cooling water channel is connected to the inlet of the first outlet pipe.

4. The thermoforming mold capable of rapidly cooling and shaping the edges of a product according to claim 3, characterized in that: The pressure ring includes an inner ring body and an outer ring body. The lower end of the outer ring body is provided with an inwardly protruding annular limiting step. The annular end face of the lower end of the inner ring body is in close contact with the upper surface of the annular limiting step. An annular groove is provided on the outer side of the inner ring body. A first water inlet and a first water outlet are provided on the upper end face of the inner ring body. A water-blocking component is provided in the annular groove to separate the annular groove. The water-blocking component is located between the first water inlet and the first water outlet. The inner side of the outer ring body closes the groove opening of the annular groove to form a C-shaped first cooling water channel. The first water inlet constitutes the water inlet end of the first cooling water channel, and the first water outlet constitutes the water outlet end of the first cooling water channel.

5. The thermoforming mold capable of rapidly cooling and shaping the edges of a product according to claim 1, characterized in that: The first cooling water channel is annular, extending circumferentially along the pressure ring. The upper end face of the pressure ring is provided with a first inlet and a first outlet that communicate with the first cooling water channel. The first inlet and the first outlet are staggered in the circumferential direction of the pressure ring. The first inlet constitutes the inlet end of the first cooling water channel, and the first outlet constitutes the outlet end of the first cooling water channel.

6. The thermoforming mold capable of rapidly cooling and shaping the edge of a product according to any one of claims 1-5, characterized in that: The upper template is provided with a first cooling water inlet channel and a first cooling water outlet channel. The inlet end of the first cooling water inlet channel and the outlet end of the first cooling water outlet channel are both located on the side or upper surface of the upper template, and the outlet end of the first cooling water inlet channel and the inlet end of the first cooling water outlet channel are both located on the lower surface of the upper template. The outlet end of the first cooling water inlet channel is connected to the inlet end of the first inlet pipe, and the outlet end of the first outlet pipe is connected to the inlet end of the first cooling water outlet channel.

7. The thermoforming mold capable of rapidly cooling and shaping the edge of a product according to any one of claims 1-5, characterized in that: The first inlet pipe and the first outlet pipe are made of plastic flexible hoses or telescopic pipes.

8. The thermoforming mold capable of rapidly cooling and shaping the edge of a product according to any one of claims 1-5, characterized in that: The upper mold also includes a stretching head, a stretching rod, a stretching rod mounting plate, and a stretching rod mounting plate lifting control mechanism. The stretching head is connected to the lower end of the stretching rod and is located in the cavity of the pressure ring. The upper end of the stretching rod is connected to the stretching rod mounting plate, and the stretching rod mounting plate is connected to the stretching rod mounting plate lifting control mechanism.

9. The thermoforming mold capable of rapidly cooling and shaping the edges of a product according to claim 8, characterized in that: The lower part of the tension rod is fitted with a tension head limiting sleeve, and the lower end of the tension head limiting sleeve is in contact with the top surface of the tension head.

10. The thermoforming mold capable of rapidly cooling and shaping the edges of a product according to any one of claims 1-5, characterized in that: The lower mold also includes an ejector rod and an ejector rod mounting plate. The forming mold includes a side mold and a movable bottom mold. The side mold is mounted on the lower mold body and is located inside the lower shearing mold. The movable bottom mold is connected to the upper end of the ejector rod. The lower end of the ejector rod extends to the bottom of the lower mold plate and is connected to the ejector rod mounting plate. The ejector rod has a cooling water inlet channel and a cooling water outlet channel running vertically. The lower end of the cooling water inlet channel is the inlet end and the upper end is the outlet end. The upper end of the cooling water outlet channel is the inlet end and the lower end is the outlet end. The movable bottom mold has a second cooling water flow channel. The outlet end of the cooling water inlet channel is connected to the inlet end of the second cooling water flow channel, and the outlet end of the second cooling water flow channel is connected to the inlet end of the cooling water outlet channel.

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