A thermoforming mold capable of smoothly demoulding a product

Abstract

A thermoforming mold capable of smoothly demoulding a product comprises an upper mold and a lower mold; the upper mold comprises an upper mold plate, an upper mold body, a stretching head, a stretching rod and a stretching rod mounting plate, the upper mold body is mounted on the upper mold plate, the upper mold body has a cavity, the lower end of the stretching rod is connected to the stretching head, the stretching head is in the cavity of the upper mold body, and the upper end of the stretching rod is connected to the stretching rod mounting plate; the lower mold comprises a lower mold plate and a forming mold, the forming mold is mounted on the lower mold plate, and the forming mold has a forming mold cavity, characterized in that: at least one blowing hole is provided on the bottom surface of the stretching head, a first air inlet channel is provided in the stretching head, and each blowing hole is connected to the air outlet end of the first air inlet channel. During the production process of the thermoforming mold of the utility model, when the mold is opened, the gas provided by the blowing device is blown out from each blowing hole after passing through the first air inlet channel, and blown toward the plastic product, overcoming the electrostatic adsorption effect of the stretching head on the plastic product, so that the plastic product is separated from the stretching head, so that the plastic product can be smoothly demoulded.

Description

Technical Field

[0001] The utility model relates to thermoforming equipment, in particular to a thermoforming mould which can smoothly demould a product. Background Art

[0002] Existing thermoforming molds for making plastic products (such as plastic cups, plastic boxes, plastic basins, plastic covers, etc.) usually include an upper mold and a lower mold; the upper mold usually includes an upper mold plate and an upper mold body, the upper mold body is installed on the upper mold plate, and the upper mold body has a cavity; the lower mold includes a lower mold plate and a molding mold, the molding mold is installed on the lower mold plate, and the molding mold has a molding cavity. The upper mold usually also includes a stretching head, a stretching rod, and a stretching rod mounting plate. The lower end of the stretching rod is connected to the stretching head, the stretching head is in the cavity of the upper mold body, and the upper end of the stretching rod is connected to the stretching rod mounting plate. Usually, the shape of the stretching head is similar to the shape of the product, but the size is slightly smaller than the product.

[0003] The upper die is usually also equipped with a stretching rod mounting plate lifting control mechanism, and the stretching rod mounting plate is connected to the stretching rod mounting plate lifting control mechanism. The stretching rod mounting plate lifting control mechanism can be arranged on the upper die plate; when the upper die is fixed on the frame, the stretching rod mounting plate lifting control mechanism can also be arranged on the frame. The stretching rod mounting plate lifting control mechanism is used to drive the stretching rod to move up and down; driven by the stretching rod, the stretching head can move up and down in the cavity of the upper die body.

[0004] Some thermoforming molds can also perform shearing after completing the molding to obtain a single plastic product. In this case, the upper mold usually also includes an upper shearing mold, which is installed on the lower side of the upper mold body. The upper shearing mold has a cavity, and the cavity of the upper shearing mold is connected to the cavity of the upper mold body. Usually, the inner edge of the lower end of the upper shearing mold is an upper shearing blade; the lower mold also includes a lower shearing mold and an ejector rod. The lower shearing mold is installed on the lower mold plate. Usually, the outer edge of the upper end of the lower shearing mold is a lower shearing blade, and the lower shearing blade matches the upper shearing blade. The molding mold includes a side mold and a movable bottom mold. The side mold is installed on the lower mold plate and is on the inner side of the lower shearing mold. The movable bottom mold is connected to the upper end of the ejector rod, and 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 above-mentioned side mold is used to mold the edge part or side wall of the plastic product; the movable bottom mold is used to mold the middle part or bottom of the plastic product.

[0005] The upper die usually also includes a press ring, which is arranged in the cavity of the upper shear die and can move up and down in the cavity of the upper shear die. When the die is closed, the press ring presses the sheet material against the lower die. When a press ring is arranged in the cavity of the upper shear die, the stretching head is in the cavity of the press ring.

[0006] When making plastic products, the plastic sheet is first heated to reach the molding temperature; the heated plastic sheet passes through the molding area, and the thermoforming mold is closed at this time. Driven by the stretching rod, the stretching head moves downward in the cavity of the upper shear mold to pre-stretch the plastic sheet so that the shape and size of the plastic sheet are close to the product; then, positive pressure thermoforming (or negative pressure thermoforming) is performed to make the plastic sheet close to the molding mold; the upper and lower shear blades complete the shearing action on the molded sheet after molding, and the plastic product is sheared out of the molded sheet to obtain a single plastic product; then the thermoforming mold is opened (the upper mold height can remain unchanged and the lower mold descends), the ejector rod mounting plate, the ejector rod and the movable bottom mold rise relative to the lower mold plate, and the plastic product is ejected from the molding mold to separate the plastic product from the molding mold.

[0007] The stretching head is usually made of engineering plastics (such as nylon). When pre-stretching the heated plastic sheet, it is in close contact with the plastic sheet and generates friction. For some plastic sheets, such as polystyrene (PS) sheets, due to the special properties of their molecular structure, they have high electrical impedance and dielectric constant, which makes the polystyrene sheets easily charged during friction, thereby generating static electricity. Therefore, when the thermoforming mold is opened, the plastic product will be attracted and attached to the stretching head due to electrostatic adsorption, resulting in the plastic product being unable to be demolded smoothly, affecting the normal progress of subsequent production. Summary of the invention

[0008] The technical problem to be solved by the utility model is to provide a thermoforming mold that can smoothly demould the product. This thermoforming mold can smoothly separate the product with static electricity (i.e., plastic product) from the stretching head during the production process, so that the product (i.e., plastic product) can be smoothly demoulded. The adopted technical solution is as follows:

[0009] A thermoforming mold capable of smoothly demoulding a product comprises an upper mold and a lower mold; the upper mold comprises an upper mold plate, an upper mold body, a stretching head, a stretching rod and a stretching rod mounting plate, the upper mold body is mounted on the upper mold plate, the upper mold body has a cavity, the lower end of the stretching rod is connected to the stretching head, the stretching head is in the cavity of the upper mold body, and the upper end of the stretching rod is connected to the stretching rod mounting plate; the lower mold comprises a lower mold plate and a forming mold, the forming mold is mounted on the lower mold plate, and the forming mold has a forming mold cavity, characterized in that: at least one blowing hole is provided on the bottom surface of the stretching head, a first air inlet channel is provided in the stretching head, and each blowing hole is connected to the air outlet end of the first air inlet channel.

[0010] During the production process of the above-mentioned thermoforming mold, when the thermoforming mold is opened, the gas provided by the blowing equipment (such as an air compressor, a compressed air source, etc.) is blown out from each blowing hole through the first air inlet channel and blown toward the plastic product, thereby overcoming the electrostatic adsorption effect of the stretching head on the plastic product, allowing the plastic product to separate from the stretching head, thereby allowing the plastic product to be smoothly demolded.

[0011] In a preferred embodiment, a second air inlet channel is provided in the stretching rod, and the air outlet end of the second air inlet channel is connected to the air inlet end of the first air inlet channel. In a more preferred embodiment, the second air inlet channel is a straight channel running up and down, the upper end of the second air inlet channel is the air inlet end, and the lower end of the second air inlet channel is the air outlet end. The air inlet end of the second air inlet channel is usually provided with an air pipe joint, and the air outlet of the blowing device is connected to the air pipe joint via an air transmission pipeline, thereby communicating with the air inlet end of the second air inlet channel.

[0012] In a specific solution, the stretching head is provided with a groove with an opening at the top, the upper part of the inner wall of the groove is provided with an internal thread, the lower end of the stretching rod is provided with an external thread section, the external thread section is screwed with the internal thread at the upper part of the inner wall of the groove, the lower part of the groove constitutes the first air inlet channel, and each blowing hole is arranged at the bottom of the groove. This structure is more convenient for processing the first air inlet channel and the blowing holes.

[0013] In another specific solution, the stretching head includes a stretching head body and a stretching head flange, a groove is provided on the top of the stretching head body, the stretching head flange is installed on the top of the stretching head body and covers the groove, the lower surface of the stretching head flange and the inner wall of the groove together form the first air inlet channel, the lower end of the stretching rod is connected to the stretching head flange, and each blowing hole is arranged at the bottom of the groove. This structure is more convenient for processing the first air inlet channel and the blowing hole.

[0014] In one specific solution, the bottom surface of the stretching head is circular, and three blowing holes are arranged on the bottom surface of the stretching head, and the three blowing holes are evenly distributed in the circumferential direction of the stretching head. In another specific solution, the bottom surface of the stretching head is rectangular, and four blowing holes are arranged on the bottom surface of the stretching head, and the four blowing holes are located at the four corners of a rectangle similar to the bottom surface of the stretching head.

[0015] The upper mold is usually also equipped with a stretching rod mounting plate lifting control mechanism, and the stretching rod mounting plate is connected to the stretching rod mounting plate lifting control mechanism. The above-mentioned stretching rod mounting plate lifting control mechanism can be arranged on the upper mold plate; when the upper mold is fixed on the frame, the stretching rod mounting plate lifting control mechanism can also be arranged on the frame. The stretching rod mounting plate lifting control mechanism is used to drive the stretching rod to move up and down; driven by the stretching rod, the stretching head can move up and down in the cavity of the upper mold body. 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 installed on the upper mold plate; when the upper mold is fixed on the frame, the cylinder body of the stretching cylinder can also be installed on the frame.

[0016] In order to ensure smooth movement of the stretching head, a stretching rod guide sleeve extending up and down is preferably provided on the upper template, and the stretching rod is located in the stretching rod guide sleeve and is in sliding cooperation with the stretching rod guide sleeve.

[0017] In the preferred embodiment, the upper mold further comprises an upper shearing mold, which is mounted on the lower side of the upper mold body, and has a cavity, and the cavity of the upper shearing mold is connected to the cavity of the upper mold body; the lower mold further comprises a lower shearing mold and an ejector rod, and the lower shearing mold is mounted on the lower mold plate, and the molding mold comprises a side mold and a movable bottom mold, and the side mold is mounted on the lower mold plate and is located on the inner side of the lower shearing mold, and the movable bottom mold is connected to the upper end of the ejector rod, and 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. Usually, the inner edge of the lower end of the upper shearing mold is the upper shearing blade; the outer edge of the upper end of the lower shearing mold is the lower shearing blade, and the lower shearing blade matches the upper shearing blade. In this way, the thermoforming mold can also complete the shearing action after completing the molding to obtain a single plastic product. The side mold is used to mold the edge part or side wall of the plastic product; the movable bottom mold is used to mold the middle part or bottom of the plastic product.

[0018] In a more preferred embodiment, an air suction channel is provided in the ejector rod, a ventilation cavity is provided in the movable bottom mold, at least one air suction hole is provided on the top surface of the movable bottom mold, the upper end of the air suction channel is connected to the ventilation cavity, and each air suction hole is connected to the ventilation cavity. The lower end of the air suction channel can be connected to a vacuum pumping device, and before the thermoforming mold is opened, the vacuum pumping device vacuums the ventilation cavity through the air suction channel, and a negative pressure is formed at the air suction hole to suck the plastic product, which can further prevent the plastic product from being lifted by the stretching head when the mold is opened; after the mold is opened, the vacuum pumping is stopped, the negative pressure at the air suction hole is released, and the plastic product is released.

[0019] In order to make the ejector rod mounting plate and the ejector rod rise and fall more smoothly, the lower template is preferably provided with an ejector rod guide sleeve extending up and down, and the ejector rod is located in the ejector rod guide sleeve and slidably cooperates with the ejector rod guide sleeve.

[0020] In a more preferred embodiment, the lower template is provided with a vertically extending tube-aligning guide column, the upper end of which is connected to the lower template, and the ejector rod mounting plate is provided with a tube-aligning guide sleeve, in which the tube-aligning guide column is located. When the ejector rod mounting plate is raised or lowered relative to the lower template, the tube-aligning guide sleeve slides along the tube-aligning guide column, which can guide the ejector rod mounting plate and the ejector rod to be raised or lowered more smoothly.

[0021] In a more preferred embodiment, the lower template is provided with a limit shaft extending upward and downward, the ejector rod mounting plate is provided with a limit through hole, the limit shaft is located in the limit through hole, the lower end of the limit shaft is sleeved with a lower limit washer, and the lower limit washer is located below the ejector rod mounting plate. During the process of the ejector rod mounting plate descending, when the lower surface of the ejector rod mounting plate contacts the upper end surface of the lower limit washer, the ejector rod mounting plate will no longer descend. The lower limit washer plays a buffering role and can be made of rubber or polyurethane elastomer.

[0022] In a more preferred embodiment, the upper mold further comprises a pressure ring, which is arranged in the cavity of the upper mold body and the upper shearing mold, and the lower end surface of the pressure ring matches and corresponds to the upper end surface of the lower shearing mold or the forming mold. In the case where a pressure ring is provided, the stretching head is located in the cavity of the pressure ring. The pressure ring can move up and down in the cavity of the upper shearing mold and can apply pressure to the plastic sheet to be formed. In a specific embodiment, a compression spring is installed between the pressure ring and the upper mold plate, and when the compression spring contracts, the pressure ring can apply a certain pressure to the plastic sheet to be formed.

[0023] In the preferred embodiment, the above-mentioned lower mold also includes a lower mold body, which is installed on the lower mold plate (when the lower mold includes a lower shear mold, the lower shear mold is installed on the lower mold body), and the forming mold is installed on the lower mold body (when the forming mold includes a side mold and a movable bottom mold, the side mold is installed on the lower mold body).

[0024] During the production process of the thermoforming mold of the utility model, when the thermoforming mold is opened, the gas provided by the blowing equipment (such as an air compressor, a compressed air source, etc.) is blown out from each blowing hole after passing through the first air inlet channel, and blown toward the plastic product, thereby overcoming the electrostatic adsorption effect of the stretching head on the plastic product, so that the plastic product is separated from the stretching head, thereby enabling the plastic product to be demoulded smoothly, ensuring the normal progress of subsequent production.

[0025] The thermoforming mold of the utility model is suitable for thermoforming of polystyrene (PS) sheets which are prone to generate static electricity. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a structural schematic diagram of a preferred embodiment 1 of the utility model;

[0027] Figure 2 yes Figure 1 A magnified view of part A;

[0028] Figure 3 This is a bottom view of the stretching head in the preferred embodiment of the utility model;

[0029] Figure 4 It is a structural schematic diagram of the stretching head in the preferred embodiment 2 of the utility model. DETAILED DESCRIPTION

[0030] Embodiment 1, as Figure 1 As shown, the thermoforming mold capable of smoothly demoulding the product comprises an upper mold 1 and a lower mold 2. The thermoforming mold of this embodiment is suitable for thermoforming of polystyrene (PS) sheets that are prone to generate static electricity, and the molded plastic product is a plastic cover made of polystyrene (PS).

[0031] The upper mold 1 includes an upper mold plate 11, an upper mold body 12, a stretching head 13, a stretching rod 14 and a stretching rod mounting plate 15. The upper mold body 12 is installed on the upper mold plate 11. The upper mold body 12 has a cavity. The lower end of the stretching rod 14 is connected to the stretching head 13. The stretching head 13 is in the cavity of the upper mold body 12. The upper end of the stretching rod 14 is connected to the stretching rod mounting plate 15. The upper mold 1 also includes an upper shearing mold 110. The upper shearing mold 110 is installed on the lower side of the upper mold body 12. The upper shearing mold 110 has a cavity. The cavity of the upper shearing mold 110 is connected to the cavity of the upper mold body 12. Figure 2 At least one (e.g., three) blowing holes 16 are provided on the bottom surface of the stretching head 13, and a first air inlet channel 17 is provided in the stretching head 13, and each blowing hole 16 is connected to the air outlet end of the first air inlet channel 17. A second air inlet channel 18 is provided in the stretching rod 14, and the air outlet end of the second air inlet channel 18 is connected to the air inlet end of the first air inlet channel 17.

[0032] In this embodiment, the stretching head 13 is made of engineering plastics (such as nylon).

[0033] In this embodiment, the second air inlet channel 18 is a straight channel running up and down, the upper end of the second air inlet channel 18 is the air inlet end, and the lower end of the second air inlet channel 18 is the air outlet end. The air inlet end of the second air inlet channel 18 is provided with an air pipe joint 19, and the air outlet of the blowing device is connected to the air pipe joint 19 through an air transmission pipeline, thereby communicating with the air inlet end of the second air inlet channel 18.

[0034] refer to Figure 2 In this embodiment, a groove 131 with an opening at the top is provided on the stretching head 13, an internal thread 132 is provided on the upper part of the inner wall of the groove 131, an external thread section 141 is provided on the lower end of the stretching rod 14, and the external thread section 141 is screwed with the internal thread 132 on the upper part of the inner wall of the groove 131. The lower part of the groove 131 constitutes the first air inlet channel 17, and each blowing hole 16 is arranged at the bottom of the groove 131. With this structure, it is easier to process the first air inlet channel 17 and the blowing holes 16.

[0035] refer to Figure 3 In this embodiment, the bottom surface 133 of the stretching head 13 is circular, and three blowing holes 16 are provided on the bottom surface 133 of the stretching head 13 . The three blowing holes 16 are evenly distributed in the circumferential direction of the stretching head 13 .

[0036] The stretching rod mounting plate 15 is connected to a stretching rod mounting plate lifting control mechanism. The stretching rod mounting plate lifting control mechanism can be arranged on the upper template; when the upper mold is fixed on the frame, the stretching rod mounting plate lifting control mechanism can also be arranged on the frame. The stretching rod mounting plate lifting control mechanism is used to drive the stretching rod 14 to move up and down; driven by the stretching rod 14, the stretching head 13 can move up and down in the cavity of the upper mold body 12 and the cavity of the upper shear mold 110. 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 installed on the upper template; when the upper mold is fixed on the frame, the cylinder body of the stretching cylinder can also be installed on the frame.

[0037] The upper mold plate 11 is provided with a stretching rod guide sleeve 111 extending up and down. The stretching rod 14 is located in the stretching rod guide sleeve 111 and is in sliding cooperation with the stretching rod guide sleeve 111 .

[0038] The lower mold 2 includes a lower mold plate 21, a molding mold, a lower shearing mold 22 and an ejector rod 23. The molding mold has a molding cavity; the molding mold includes a side mold 24 and a movable bottom mold 25, the side mold 24 is located inside the lower shearing mold 22, the movable bottom mold 25 is connected to the upper end of the ejector rod 23, and the lower end of the ejector rod 23 extends below the lower mold plate 21 and is connected to the ejector rod mounting plate 26. The inner edge of the lower end of the upper shearing mold 110 is an upper shearing blade; the outer edge of the upper end of the lower shearing mold 22 is a lower shearing blade, and the lower shearing blade matches the upper shearing blade. The side mold 24 is used to mold the edge part of the plastic cover, and the movable bottom mold 25 is used to mold the middle part of the plastic cover. In this embodiment, the lower mold 2 also includes a lower mold body 213, the lower mold body 213 is installed on the lower mold plate 21, the lower shearing mold 22 is installed on the lower mold body 213, and the side mold 24 is installed on the lower mold body 213.

[0039] refer to Figure 2 In this embodiment, an air suction channel 214 is provided in the ejector rod 23, a ventilation cavity 215 is provided in the movable bottom mold 25, and a plurality of air suction holes 216 are provided on the top surface of the movable bottom mold 25. The upper end of the air suction channel 214 is connected to the ventilation cavity 215, and each air suction hole 216 is connected to the ventilation cavity 215.

[0040] The lower mold plate 21 is provided with an ejector rod guide sleeve 27 extending up and down, and the ejector rod 23 is located in the ejector rod guide sleeve 27 and is in sliding cooperation with the ejector rod guide sleeve 27 .

[0041] The lower template 21 is provided with a pipe-aligning guide column 28 extending upward and downward, the upper end of which is connected to the lower template 21, and the ejector rod mounting plate 26 is provided with a pipe-aligning guide sleeve 29, in which the pipe-aligning guide column 28 is located. When the ejector rod mounting plate 26 is raised or lowered relative to the lower template 21, the pipe-aligning guide sleeve 29 slides along the pipe-aligning guide column 28, and can guide the ejector rod mounting plate 26 and the ejector rod 23 to be raised or lowered smoothly.

[0042] The lower template 21 is provided with a limit shaft 210 extending upward and downward, and the ejector rod mounting plate 26 is provided with a limit through hole 211. The limit shaft 210 is located in the limit through hole 211. The lower end of the limit shaft 210 is sleeved with a lower limit washer 212, and the lower limit washer 212 is located below the ejector rod mounting plate 26. During the descending process 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 limit washer 212, the ejector rod mounting plate 26 stops descending. The lower limit washer 212 plays a buffering role and can be made of rubber or polyurethane elastomer.

[0043] In this embodiment, the upper mold 1 further includes a press ring 112, which is disposed in the cavity of the upper shearing mold 110, and the lower end surface of the press ring 112 matches and corresponds to the upper end surface of the lower shearing mold 22. The stretching head 13 is in the cavity of the press ring 112. A compression spring 113 is installed between the press ring 112 and the upper mold plate 11, and when the compression spring 113 contracts, the press ring 112 can apply a certain pressure to the plastic sheet to be formed.

[0044] The following is a brief description of the working principle of this thermoforming mold:

[0045] When making plastic products, the plastic sheet is first heated to reach the molding temperature; the heated plastic sheet passes through the molding area, and the thermoforming mold is closed at this time, and the compression spring 113 applies a downward thrust to the pressing ring 112, so that the pressing ring 112 presses the sheet against the upper end surface of the lower shearing mold 22, and a molding air chamber is formed between the plastic sheet and the cavity of the upper shearing mold 110;

[0046] Then the stretching rod mounting plate lifting control mechanism drives the stretching rod mounting plate 15 to descend, and the stretching rod mounting plate 15, the stretching rod 14, and the stretching head 13 descend together; the stretching head 13 pre-stretches the plastic sheet;

[0047] Then, compressed air enters the above-mentioned forming air chamber. Under the action of the compressed air, the plastic sheet is pressed against the forming mold to form the plastic sheet. Cooling water can be introduced into the circulating cooling water path in the mold to cool the forming mold (side mold 24 and movable bottom mold 25) to shape the formed sheet.

[0048] Then the lower mold 2 rises further, and the lower shearing blade at the upper outer edge of the lower shearing mold 22 cooperates with the upper shearing blade at the lower inner edge of the upper shearing mold 110 to shear the shaped sheet, and cut the plastic product out of the shaped sheet to obtain a single plastic product; at this time, the vacuum device vacuums the ventilation cavity 215 through the suction channel 214, and a negative pressure is formed at the suction hole 216 to suck the plastic product;

[0049] Then the lower mold 2 descends, and the edge of the plastic product leaves the pressing ring 112 (the thermoforming mold is opened); at this time, the gas provided by the blowing device (such as an air compressor, a compressed air source, etc.) is blown out from the blowing holes 16 through the second air inlet channel 18 and the first air inlet channel 17, and blown toward the plastic product, overcoming the electrostatic adsorption effect of the stretching head 13 on the plastic product, so that the plastic product is separated from the stretching head 13;

[0050] Then, the stretching rod mounting plate lifting control mechanism drives the stretching rod mounting plate 15, the stretching rod 14, and the stretching head 13 to rise together, and the stretching head 13 returns to the cavity of the upper shearing mold 110; the ejector rod mounting plate 26, the ejector rod 23, and the movable bottom mold 25 rise, and eject the plastic product;

[0051] Then the robot reaches between the upper mold 1 and the lower mold 2 to take out the plastic product (before the robot touches the plastic product, the vacuum device stops vacuuming, the negative pressure at the suction hole 216 is released, and the plastic product is released), thus completing a thermoforming process. Then the ejector mounting plate 26 and the ejector rod 23 descend and drive the movable bottom mold 25 to descend to the required molding position, preparing for the next thermoforming process.

[0052] Example 2, reference Figure 4 In this embodiment, the stretching head 13 includes a stretching head body 134 and a stretching head flange 135. A groove 131 is provided on the top of the stretching head body 134. The stretching head flange 135 is installed on the top of the stretching head body 134 and covers the groove 131. The lower surface of the stretching head flange 135 and the inner wall of the groove 131 together form a first air inlet channel 17. The lower end of the stretching rod 14 is connected to the stretching head flange 135, and each blowing hole 16 is arranged at the bottom of the groove 131.

[0053] The rest of the structure of this embodiment is the same as that of Embodiment 1.

Claims

1. A thermoforming mold capable of smoothly demoulding a product, comprising an upper mold and a lower mold; the upper mold comprises an upper mold plate, an upper mold body, a stretching head, a stretching rod and a stretching rod mounting plate, the upper mold body is mounted on the upper mold plate, the upper mold body has a cavity, the lower end of the stretching rod is connected to the stretching head, the stretching head is in the cavity of the upper mold body, and the upper end of the stretching rod is connected to the stretching rod mounting plate; the lower mold comprises a lower mold plate and a forming mold, the forming mold is mounted on the lower mold plate, and the forming mold has a forming mold cavity, characterized in that: At least one blowing hole is arranged on the bottom surface of the stretching head, a first air inlet channel is arranged in the stretching head, and each blowing hole is communicated with the air outlet end of the first air inlet channel.

2. The thermoforming mold capable of smoothly demoulding the product according to claim 1, characterized in that: A second air inlet channel is provided in the stretching rod, and an air outlet end of the second air inlet channel is communicated with an air inlet end of the first air inlet channel.

3. The thermoforming mold capable of smoothly demoulding the product according to claim 2, characterized in that: The second air inlet channel is a straight channel running up and down, the upper end of the second air inlet channel is the air inlet end, and the lower end of the second air inlet channel is the air outlet end.

4. The thermoforming mold capable of smoothly demoulding the product according to any one of claims 1 to 3, characterized in that: The stretching head is provided with a groove with a top opening, the upper part of the inner wall of the groove is provided with an internal thread, the lower end of the stretching rod is provided with an external thread section, the external thread section is screwed with the internal thread on the upper part of the inner wall of the groove, the lower part of the groove constitutes the first air inlet channel, and each blowing hole is arranged at the bottom of the groove.

5. The thermoforming mold capable of smoothly demoulding the product according to any one of claims 1 to 3, characterized in that: The stretching head includes a stretching head body and a stretching head flange. A groove is provided on the top of the stretching head body. The stretching head flange is installed on the top of the stretching head body and covers the groove. The lower surface of the stretching head flange and the inner wall of the groove together form the first air inlet channel. The lower end of the stretching rod is connected to the stretching head flange, and each blowing hole is arranged at the bottom of the groove.

6. The thermoforming mold capable of smoothly demoulding the product according to any one of claims 1 to 3, characterized in that: The upper mold also includes an upper shearing mold, which is installed on the lower side of the upper mold body. The upper shearing mold has a cavity, and the cavity of the upper shearing mold is connected to the cavity of the upper mold body; the lower mold also includes a lower shearing mold and an ejector rod, the lower shearing mold is installed on the lower mold plate, the molding mold includes a side mold and a movable bottom mold, the side mold is installed on the lower mold plate and is located on the inner side of the lower shearing mold, the movable bottom mold is connected to the upper end of the ejector rod, and 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.

7. The thermoforming mold capable of smoothly demoulding the product according to claim 6, characterized in that: The ejector rod is provided with an air suction channel, the movable bottom mold is provided with an air vent cavity, the top surface of the movable bottom mold is provided with at least one air suction hole, the upper end of the air suction channel is connected with the air vent cavity, and each air suction hole is connected with the air vent cavity.

8. The thermoforming mold capable of smoothly demoulding the product according to claim 6, characterized in that: The lower template is provided with an ejector rod guide sleeve extending upward and downward, the ejector rod is located in the ejector rod guide sleeve and is in sliding cooperation with the ejector rod guide sleeve; The lower template is provided with a tube aligning guide column which runs up and down, the upper end of which is connected to the lower template, and the ejector rod mounting plate is provided with a tube aligning guide sleeve, in which the tube aligning guide column is located; The lower template is provided with a limit shaft running up and down, the ejector rod mounting plate is provided with a limit through hole, the limit shaft is located in the limit through hole, the lower end of the limit shaft is sleeved with a lower limit washer, and the lower limit washer is located below the ejector rod mounting plate.

9. The thermoforming mold capable of smoothly demoulding the product according to claim 6, characterized in that: The upper die also includes a pressure ring, which is arranged in the cavity of the upper die body and the upper shear die. The lower end surface of the pressure ring matches the upper end surface of the lower shear die or the forming die and has a corresponding position.

10. The thermoforming mold capable of smoothly demoulding a product according to any one of claims 1 to 3, characterized in that: The lower mold also includes a lower mold body, which is installed on the lower mold plate, and the forming mold is installed on the lower mold body.

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