Blister mechanism of a full-automatic blister forming machine

Abstract

The application provides a full-automatic blister forming machine's blister mechanism and relates to the technical field of the blister forming machine.The full-automatic blister forming machine's blister mechanism comprises the following parts: an upper die, the upper die comprises an upper die base and an upper die core, the upper die core is connected to the lower surface of the upper die base; a lower die, the lower die comprises a lower die base and a lower die core, the lower die core is connected to the upper surface of the lower die base, the upper die core and the lower die core form a forming cavity when they are closed; a limiting mechanism, the limiting mechanism comprises a sliding rod and positioning blocks, two positioning blocks are respectively connected to the side surfaces of the upper die core and the lower die core, one end of the sliding rod is connected to the upper die core, and the other end of the sliding rod is sequentially slid from top to bottom through the two positioning blocks.When the upper die core is lowered and closed with the lower die core, the sliding rod is directionally slid in the two positioning blocks, the mold cavity of the upper die core and the lower die core are forced to be accurately aligned, the horizontal deviation is effectively prevented, the consistency of the forming cavity is ensured every time the mold is closed, and the wall thickness uniformity and the forming precision of the blister product are improved.

Description

Technical Field

[0001] This invention relates to the field of vacuum forming machine technology, and in particular to a vacuum forming mechanism for a fully automatic vacuum forming machine. Background Technology

[0002] A vacuum forming machine is a device that heats and softens thermoplastic sheets, then uses vacuum suction or compressed air to form the shape, and finally uses a mold to fix the shape to manufacture products of various shapes. In a typical vacuum forming process, the upper and lower molds close together to form a closed cavity, and the positioning accuracy of the mold directly determines the wall thickness distribution and dimensional consistency of the product.

[0003] Existing vacuum forming equipment typically uses guide pillars and guide sleeves between the upper and lower mold bases as a mold closing guide structure. This guide arrangement is located around the mold and mainly constrains the movement trajectory of the mold base. However, due to the tensile stress of the sheet material and local thermal expansion differences that the mold core body bears during operation, the guide system around the mold base alone is insufficient to completely suppress the lateral displacement of the mold core itself. Under continuous high-speed production conditions, as the frequency of mold opening and closing increases, the wear gap of the guide elements gradually widens, and the mold core is prone to slight lateral movement at the moment of mold closing, which in turn causes misalignment of the cavity wall surface. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings of existing technologies by proposing a vacuum forming mechanism for a fully automatic vacuum forming machine.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A vacuum forming mechanism for a fully automatic vacuum forming machine includes: The upper mold includes an upper mold base and an upper mold core, with the upper mold core connected to the lower surface of the upper mold base; The lower mold includes a lower mold base and a lower mold core. The lower mold core is connected to the upper surface of the lower mold base. When the upper mold core and the lower mold core are closed, a cavity is formed. The limiting mechanism includes a slide rod and positioning blocks. The two positioning blocks are respectively connected to the sides of the upper mold core and the lower mold core. One end of the slide rod is connected to the upper mold core, and the other end of the slide rod slides through the two positioning blocks from top to bottom.

[0006] Preferably, a slot is provided on the outer peripheral surface of the slide bar, and the vacuum forming mechanism also includes a positioning unit. The positioning unit includes a thermal expansion extension rod and a locking block. The thermal expansion extension rod is installed in the upper mold core. One end of the thermal expansion extension rod is connected to the mold cavity of the upper mold core, and the other end of the thermal expansion extension rod is connected to the locking block. The thermal expansion extension rod can extend axially when the injection molding is heated and push the locking block into the slot.

[0007] Preferably, the end of the thermal expansion extension rod that is connected to the upper mold core cavity has a smooth transition between the end face of the thermal expansion extension rod and the inner wall of the mold cavity.

[0008] Preferably, a seal is provided between the thermal expansion extension rod and the upper mold core.

[0009] Preferably, after the card block is inserted into the card slot, the movement of the upper mold core relative to the lower mold core in the mold opening direction is restricted.

[0010] Preferably, the vacuum forming mechanism of the fully automatic vacuum forming machine also includes an air cooling mechanism. The air cooling mechanism includes a pressure rod, a corrugated tube, an air pipe, and an air rod. The pressure rod is movably positioned between the upper mold core and the lower mold core. The bottom end of the pressure rod is connected to the top end of the corrugated tube, which is a closed cavity. One end of the air pipe is connected to the interior of the corrugated tube, and the other end is connected to the air rod. The air rod is installed on the lower mold core and can extend upward into the mold cavity of the lower mold core. During the mold closing process, the upper mold core presses down on the pressure rod to compress the corrugated tube, causing gas to be blown out from the air rod through the air pipe.

[0011] Preferably, a spring is provided inside the bellows, with the two ends of the spring abutting against the inner top surface and the inner bottom surface of the bellows, respectively.

[0012] Preferably, the air rod continuously blows air upwards during the process from contact between the upper mold core and the lower mold core until the mold is fully closed.

[0013] Preferably, in the open mold state, the top of the pressure bar protrudes above the upper surface of the lower mold core.

[0014] Compared with the prior art, the beneficial effects of the present invention are: When the upper mold core moves down and closes with the lower mold core, the slide bar slides directionally within the two positioning blocks, forcing the mold cavities of the upper and lower mold cores to be precisely aligned, effectively preventing lateral displacement. Thus, this guide and limiting structure ensures the consistency of the cavity each time the mold closes, improving the wall thickness uniformity and forming accuracy of the vacuum-formed product. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the vacuum forming mechanism of the fully automatic vacuum forming machine proposed in this invention; Figure 2 This is a front view of the vacuum forming mechanism of the fully automatic vacuum forming machine proposed in this invention; Figure 3 This is a top view of the vacuum forming mechanism of the fully automatic vacuum forming machine proposed in this invention; Figure 4 for Figure 3 Sectional view along line AA in the middle; Figure 5 for Figure 4 Enlarged view of the structure at point A in the image; Figure 6 This is a schematic diagram showing the state of the upper mold core and lower mold core after the locking block is inserted into the slot when the mold is closed in the vacuum forming mechanism of the fully automatic vacuum forming machine proposed in this invention; Figure 7 for Figure 6 Enlarged view of the structure at point B in the image.

[0016] In the diagram: 1. Upper mold; 11. Upper mold base; 12. Upper mold core; 2. Lower mold; 21. Lower mold base; 22. Lower mold core 2; 3. Air cooling mechanism; 31. Pressure rod; 32. Bellows; 33. Spring; 34. Air pipe; 35. Air rod; 4. Limiting mechanism; 41. Slide rod; 411. Slot; 42. Positioning block; 43. Positioning unit; 431. Thermal expansion extension rod; 432. Locking block. Detailed Implementation

[0017] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0018] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0019] The terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature.

[0020] Combination Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 and Figure 7 This invention provides a vacuum forming mechanism for a fully automatic vacuum forming machine, comprising: Upper mold 1, which includes upper mold base 11 and upper mold core 12, with upper mold core 12 connected to the lower surface of upper mold base 11; The lower mold 2 includes a lower mold base 21 and a lower mold core 22. The lower mold core 22 is connected to the upper surface of the lower mold base 21. When the upper mold core 12 and the lower mold core 22 are closed, a cavity is formed. The limiting mechanism 4 includes a slide rod 41 and a positioning block 42. The two positioning blocks 42 are respectively connected to the sides of the upper mold core 12 and the lower mold core 22. One end of the slide rod 41 is connected to the upper mold core 12, and the other end of the slide rod 41 slides through the two positioning blocks 42 from top to bottom.

[0021] Specifically, in the limiting mechanism 4, two positioning blocks 42 are respectively fixed to the same side of the upper mold core 12 and the lower mold core 22 by bolts. The sliding rod 41 is arranged vertically, and its upper end is fixed to the connecting lug on the side wall of the upper mold core 12. The rod body slides through the center hole of the two positioning blocks 42 in sequence. The fit clearance between the sliding rod 41 and the positioning blocks 42 is controlled within the sliding guide accuracy to ensure that the upper mold core 12 can only move in the opening and closing direction relative to the lower mold core 22.

[0022] In this optional embodiment, when the upper mold core 12 moves down to close with the lower mold core 22, the slide rod 41 slides directionally within the two positioning blocks 42, forcing the mold cavities of the upper mold core 12 and the lower mold core 22 to be precisely aligned, effectively preventing lateral displacement. Thus, this guide and limiting structure ensures the consistency of the cavity each time the mold closes, improving the wall thickness uniformity and molding accuracy of the thermoformed product.

[0023] Optionally, a slot 411 is provided on the outer peripheral surface of the slide bar 41. The vacuum forming mechanism also includes a positioning unit 43, which includes a thermal expansion extension rod 431 and a locking block 432. The thermal expansion extension rod 431 is installed inside the upper mold core 12. One end of the thermal expansion extension rod 431 is connected to the mold cavity of the upper mold core 12, and the other end of the thermal expansion extension rod 431 is connected to the locking block 432. The thermal expansion extension rod 431 can axially extend when the injection molding is heated and push the locking block 432 into the slot 411.

[0024] Specifically, a rectangular cross-section groove 411 is machined on the slide rod 41. The locking unit 43 is installed inside the upper mold core 12 and includes a thermal expansion extension rod 431 and a locking block 432. The thermal expansion extension rod 431 is made of a metal material with a high coefficient of thermal expansion. Its inner end face is flush with the mold cavity wall of the upper mold core 12 and directly contacts the mold cavity. Its outer end is connected to the locking block 432 by threads or integral molding. The engaging end of the locking block 432 faces the groove 411 of the slide rod 41. When the mold cavity is heated, the thermal expansion extension rod 431 absorbs heat and generates directional axial elongation, driving the locking block 432 to move laterally and embed into the groove 411 of the slide rod 41.

[0025] In this optional embodiment, during the heating stage of thermoforming injection molding, no additional pneumatic or electric actuators are required. The thermal expansion extension rod 431 can be triggered solely by the process heat of the cavity itself, pushing the locking block 432 into the locking slot 411. This purely mechanical thermal locking scheme achieves automatic locking of the upper mold core 12 and the lower mold core 22 under hot conditions, effectively resisting the expansion force of the high-pressure melt in the cavity. The structure is simple and the response is synchronized with the process.

[0026] Furthermore, at one end of the thermal expansion extension rod 431 that is connected to the mold cavity of the upper mold core 12, the end face of the thermal expansion extension rod 431 smoothly transitions with the inner wall of the mold cavity.

[0027] Specifically, the end face of the thermal expansion extension rod 431 located on the mold cavity side of the upper mold core 12 is finely ground to ensure that it is completely coplanar with the forming wall surface inside the mold cavity, without any bosses or pits. The assembly gaps around it are filled with high-temperature resistant filler to ensure a smooth transition between the sensing end of the thermal expansion extension rod 431 and the sheet forming surface.

[0028] In this optional embodiment, the end face is smoothly set to the mold cavity wall, so that the sheet will not produce local deformation or marks when pressed into this area during molding. Thus, while achieving the heat-locking function, it completely avoids damage to the appearance of the thermoformed product due to the intervention of the locking structure within the mold cavity, ensuring the high quality of the molded surface.

[0029] Optionally, a seal is provided between the thermal expansion extension rod 431 and the upper mold core 12.

[0030] Specifically, at least one high-temperature resistant fluororubber sealing ring is provided between the rod body of the thermal expansion extension rod 431 and the mounting hole of the upper mold core 12. This sealing ring tightly fits the circumferential surface of the rod body, completely isolating the mold cavity from the mechanically active area at the rear end of the thermal expansion extension rod 431.

[0031] In this optional embodiment, by adding a sealing element, high-temperature molten plastic or gas that may seep in during the molding process is effectively blocked, preventing the thermal expansion extension rod 431 from jamming or malfunctioning due to material intrusion. This ensures that the locking block 432 can reliably perform the thermal expansion locking action for a long time, extending the service life of the limiting mechanism 4.

[0032] Furthermore, when the card block 432 is engaged in the card slot 411, it restricts the upper mold core 12 from moving relative to the lower mold core 22 in the mold opening direction.

[0033] Specifically, the front end of the locking block 432 adopts a wedge-shaped design, and the corresponding locking groove 411 is a wedge-shaped groove at the same angle. When the thermal expansion extension rod 431 pushes the locking block 432 into the locking groove 411, the self-locking effect of the wedge surface prevents the locking block 432 from disengaging under vibration or reverse force. At the same time, the engagement depth of the locking block 432 and the locking groove 411 is sufficient to withstand the maximum expansion force of the cavity, directly locking the vertical displacement of the upper mold core 12 relative to the lower mold core 22.

[0034] In this optional embodiment, once the locking block 432 engages with the slot 411, it forms a rigid mechanical stop, clearly restricting the movement of the upper mold core 12 along the mold opening direction. This locking state does not rely on continuous heating or air pressure, maintaining a stable mold clamping force throughout the pressure holding and cooling process, completely eliminating micro-mold opening problems caused by internal mold pressure fluctuations, and ensuring the dimensional accuracy of the product.

[0035] Optionally, the vacuum forming mechanism of the fully automatic vacuum forming machine also includes an air cooling mechanism 3. The air cooling mechanism 3 includes a pressure rod 31, a corrugated tube 32, an air pipe 34, and an air rod 35. The pressure rod 31 is movably disposed between the upper mold core 12 and the lower mold core 22. The bottom end of the pressure rod 31 is connected to the top end of the corrugated tube 32, which is a closed cavity. One end of the air pipe 34 is connected to the interior of the corrugated tube 32, and the other end is connected to the air rod 35. The air rod 35 is installed on the lower mold core 22 and can extend upward into the mold cavity of the lower mold core 22. During the mold closing process, the upper mold core 12 presses down the pressure rod 31 to compress the corrugated tube 32, so that the gas is blown out from the air rod 35 through the air pipe 34.

[0036] Specifically, the air-cooling mechanism 3 includes a vertically arranged pressure rod 31, the bottom end of which is welded and fixed to the top end of a retractable metal bellows 32. The bellows 32 is a fully enclosed cavity, and its bottom is connected to an air rod 35 installed at the bottom of the lower mold core 22 via an air pipe 34. The air nozzle of the air rod 35 faces upward and can extend into the bottom area of ​​the mold cavity of the lower mold core 22. When the mold is closed, the bottom of the descending upper mold core 12 first contacts and presses down the pressure rod 31, compressing the bellows 32, reducing its internal volume, forcing air into the air pipe 34, and finally spraying it upward from the air rod 35, directly blowing it onto the lower surface of the formed sheet.

[0037] In this optional embodiment, the mechanical energy of the mold closing action drives the bellows 32 to compress and supply air, achieving automatic air cooling during the mold closing process. The generation of this cooling airflow is completely synchronized with the equipment operation, without consuming additional electrical energy. Air is blown onto the formed sheet immediately after mold closing, accelerating the cooling and shaping of the sheet, thereby shortening the molding cycle and improving production efficiency.

[0038] Furthermore, a spring 33 is provided inside the bellows 32, with the two ends of the spring 33 abutting against the inner top surface and the inner bottom surface of the bellows 32, respectively.

[0039] Specifically, a helical compression spring 33 is coaxially mounted in the internal cavity of the bellows 32. The upper and lower ends of the spring 33 abut against the inner top wall and inner bottom wall of the bellows 32, respectively. The preload of the spring 33 is designed to overcome the deformation resistance of the bellows 32 itself, allowing it to quickly return to its original position without external force.

[0040] In this optional embodiment, after the mold opens, the upper mold core 12 moves upward, the pressure on the pressure rod 31 disappears, the elastic potential energy stored in the spring 33 is released, the bellows 32 is forced to extend axially and return to its initial height, and air is drawn in from the air rod 35 to reserve for the next cycle. The spring 33 ensures that the bellows 32 can reliably reset after each compression, ensuring the stability and durability of the air-cooling cycle.

[0041] Optionally, the air rod 35 continuously blows air upwards during the process from contact between the upper mold core 12 and the lower mold core 22 until the mold is fully closed.

[0042] Specifically, the compression stroke of the pressure rod 31 coincides with the mold closing contact stroke of the upper mold core 12 and the lower mold core 22. When the upper mold core 12 just contacts the sheet material on the lower mold core 22 that is not yet fully closed, the pressure rod 31 has been pressed down a certain distance, the bellows 32 begins to exhaust air, and the air rod 35 begins to blow air; as the upper mold core 12 continues to be pressed down until the mold is fully closed, the pressure rod 31 is pressed down to the bottom in sync. At this time, the bellows 32 is compressed to its shortest length, and the air rod 35 continues to blow air.

[0043] In this optional embodiment, air is continuously blown during the mold closing dynamic process, forming an airflow curtain from pre-closure to full mold closing. This continuous airflow can drive away residual air before the sheet material is bonded to the mold core 22, allowing the sheet material to adhere to the mold surface as early as possible, and gradually cooling the molding area in conjunction with the mold closing action, effectively improving the molding integrity and surface replication of the deep cavity.

[0044] Furthermore, in the open mold state, the top of the pressure rod 31 protrudes above the upper surface of the lower mold core 22.

[0045] Specifically, the pressure rod 31 is fixed to the lower mold base 21 by a mounting seat, and its top end is a certain distance above the upper surface of the lower mold core 22 in a free state. This distance is determined according to the mold closing stroke and the compression amount of the bellows 32, so that the lower surface of the upper mold core 12 will touch the pressure rod 31 before contacting the sheet of the lower mold core 22.

[0046] In this optional embodiment, the top of the pressure rod 31 extends above the lower mold core 22, ensuring the "air blowing before closing" sequence during the mold closing action. The upper mold core 12 activates the air rod 35 to blow air before compacting the sheet, using the airflow to pre-shape the sheet and adhere it to the lower mold core 22 before fully closing the cavity. This effectively prevents gas trapping caused by premature mold closing, improving venting and molding effects.

[0047] While the present invention has been disclosed above, its scope of protection is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention, and all such changes and modifications will fall within the scope of protection of the present invention.

Claims

1. A vacuum forming mechanism for a fully automatic vacuum forming machine, characterized in that, include: The upper mold (1) includes an upper mold base (11) and an upper mold core (12), the upper mold core (12) being connected to the lower surface of the upper mold base (11); The lower mold (2) includes a lower mold base (21) and a lower mold core (22). The lower mold core (22) is connected to the upper surface of the lower mold base (21). When the upper mold core (12) and the lower mold core (22) are closed, a cavity is formed. The limiting mechanism (4) includes a slide rod (41) and a positioning block (42). The two positioning blocks (42) are respectively connected to the sides of the upper mold core (12) and the lower mold core (22). One end of the slide rod (41) is connected to the upper mold core (12), and the other end of the slide rod (41) slides through the two positioning blocks (42) from top to bottom.

2. The vacuum forming mechanism of the fully automatic vacuum forming machine according to claim 1, characterized in that, The slide bar (41) has a slot (411) on its outer circumferential surface. The vacuum forming mechanism of the fully automatic vacuum forming machine also includes a positioning unit (43). The positioning unit (43) includes a thermal expansion extension rod (431) and a locking block (432). The thermal expansion extension rod (431) is installed in the upper mold core (12). One end of the thermal expansion extension rod (431) is connected to the mold cavity of the upper mold core (12), and the other end of the thermal expansion extension rod (431) is connected to the locking block (432). The thermal expansion extension rod (431) can extend axially when the injection molding is heated and push the locking block (432) into the slot (411).

3. The vacuum forming mechanism of the fully automatic vacuum forming machine according to claim 2, characterized in that, The end of the thermal expansion extension rod (431) is connected to the mold cavity of the upper mold core (12), and the end face of the thermal expansion extension rod (431) smoothly transitions to the inner wall of the mold cavity.

4. The vacuum forming mechanism of the fully automatic vacuum forming machine according to claim 3, characterized in that, A seal is provided between the thermal expansion extension rod (431) and the upper mold core (12).

5. The vacuum forming mechanism of the fully automatic vacuum forming machine according to claim 4, characterized in that, When the card block (432) is engaged in the card slot (411), it restricts the upper mold core (12) from moving relative to the lower mold core (22) in the mold opening direction.

6. The vacuum forming mechanism of the fully automatic vacuum forming machine according to claim 5, characterized in that, The vacuum forming mechanism of the fully automatic vacuum forming machine also includes an air cooling mechanism (3). The air cooling mechanism (3) includes a pressure rod (31), a corrugated tube (32), an air pipe (34), and an air rod (35). The pressure rod (31) is movably disposed between the upper mold core (12) and the lower mold core (22). The bottom end of the pressure rod (31) is connected to the top end of the corrugated tube (32). The corrugated tube (32) is a closed cavity. One end of the air pipe (34) is connected to the interior of the corrugated tube (32), and the other end is connected to the air rod (35). The air rod (35) is installed on the lower mold core (22) and can extend upward into the mold cavity of the lower mold core (22). During the mold closing process, the upper mold core (12) presses down the pressure rod (31) to compress the corrugated tube (32), so that the gas is blown out from the air rod (35) through the air pipe (34).

7. The vacuum forming mechanism of the fully automatic vacuum forming machine according to claim 6, characterized in that, A spring (33) is provided inside the corrugated pipe (32), and the two ends of the spring (33) abut against the inner top surface and the inner bottom surface of the corrugated pipe (32) respectively.

8. The vacuum forming mechanism of the fully automatic vacuum forming machine according to claim 7, characterized in that, The air rod (35) continuously blows air upwards during the process from contact to complete mold closing between the upper mold core (12) and the lower mold core (22).

9. The vacuum forming mechanism of the fully automatic vacuum forming machine according to claim 8, characterized in that, In the open mold state, the top of the pressure bar (31) is higher than the upper surface of the lower mold core (22).

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