A forming device for bushing pipe production

Abstract

The application relates to the technical field of plastic forming, and particularly discloses a forming device for bushing pipe production, which comprises a machine body, an extruding device arranged on the machine body, a blowing device, a blow molding die and a controller, the blow molding die comprises an outer die set and an inner die set arranged in the outer die set, the outer die set comprises two symmetrically arranged outer die shells, the inner die set comprises two symmetrically arranged inner die shells, the two inner die shells are respectively arranged in the corresponding outer die shells and are attached to the corresponding outer die shells, and channels for conveying cooling gas are arranged on the outer die shells; the machine body is provided with a driving piece one for driving the two outer die shells to open and close and a driving piece two for driving the two inner die shells to open and close. When the forming device for bushing pipe production is used for blow molding of a plastic parison, the two outer die shells are driven to move away from each other, negative pressure is temporarily formed between the outer die shells and the inner die shells, and cooling gas can quickly fill the channels and cool the inner die shells.

Description

Technical Field

[0001] This invention relates to the field of plastic molding technology, and more specifically to a molding apparatus for producing bushing tubes. Background Technology

[0002] Blow molding is an efficient and flexible plastic processing method suitable for manufacturing bushings of various shapes and sizes. In the blow molding process, the plastic raw material is first heated and softened, then a preform is formed through extrusion or injection molding. The preform is placed in a blow mold, and compressed air is injected to expand it until it fills the mold and reaches the desired shape and size. Finally, after cooling and solidification, the finished bushing is obtained. If the mold temperature is too high before the plastic cools and solidifies, it may cause deformation, cracking, or other quality problems in the product. Therefore, after the molten plastic is injected into the mold and blown, the mold temperature needs to be reduced immediately and effectively to ensure that the product maintains a stable shape during the cooling process.

[0003] Chinese patent application CN118810007A discloses a cooling system for a blow molding machine, including an air compressor, a circulating chiller, a mold, and a blow rod. The outlet pipe of the circulating chiller is connected to the inlet of the mold and the blow rod, and the return pipe of the circulating chiller is connected to the outlet of the mold and the blow rod. The air compressor and the blow rod are connected by an air pipe, part of which is located inside the liquid tank of the circulating chiller. This patent application uses the circulating chiller to cool the coolant and compressed air, thereby cooling the exterior of the product with the mold and the interior with the compressed air. Through bidirectional cooling of water and air, the cooling time is reduced and the production efficiency is improved.

[0004] However, in actual implementation, compressed air is blown into the plastic blank through the blow needle rod to make the blank expand and deform. If the compressed air is directly cooled, the cooling gas blown into the blank may cause the blank to fail to flow and fill fully in the mold, resulting in incomplete product shape or defects. Moreover, the cooling gas may cause condensation phenomena such as orange peel texture and pitting on the surface of the product.

[0005] Furthermore, turning on the circulating refrigeration unit after the plastic preform has been blown into shape, causing the coolant to circulate in the mold's pipes, will result in uneven and insufficient cooling of the mold, which will also affect the molding effect and quality of the product.

[0006] Therefore, there is a need in the art for a forming apparatus for bushing production to solve the above problems. Summary of the Invention

[0007] This invention provides a molding apparatus for bushing production, which aims to solve the problems in related technologies, such as the use of cooling gas to blow-mold the inside of plastic blanks, which causes the plastic blanks to fail to expand fully due to sudden cooling, and the use of water cooling to circulate and cool the mold, which causes uneven cooling of the mold cavity and affects the yield.

[0008] The present invention provides a forming apparatus for producing bushing tubes, comprising a machine body, an extrusion device, an air blowing device, a blow molding die, and a controller disposed on the machine body. The blow molding die comprises an outer mold assembly and an inner mold assembly disposed within the outer mold assembly. The outer mold assembly comprises two symmetrically arranged outer mold shells, and the inner mold assembly comprises two symmetrically arranged inner mold shells. The two inner mold shells are respectively disposed within the corresponding outer mold shells and are fitted to the corresponding outer mold shells. The outer mold shells are provided with channels for conveying cooling gas.

[0009] The machine body is equipped with a drive component 1 for opening and closing two outer mold shells and a drive component 2 for opening and closing two inner mold shells. When cooling is required, the controller controls the drive component 1 to drive the two outer mold shells to move away from each other, creating a negative pressure between the outer and inner mold shells. Cooling gas is then rapidly filled from the channel between the outer and inner mold shells to cool the inner mold shells.

[0010] This invention sets up a double-layer mold consisting of an outer mold shell and an inner mold shell. During the blow molding of a tubular plastic preform, the two outer mold shells are driven to move away from each other, creating a brief negative pressure between the outer and inner mold shells. This allows cooling gas to quickly fill the space between the outer and inner mold shells, cooling the inner mold shell. This improves upon the problem of uneven cooling of the inner mold shell caused by the inability of coolant to immediately fill all cooling pipes during the blow molding of the plastic preform when using cooling pipes. Furthermore, after the outer mold shell is pulled apart to the left and right sides from the outside of the inner mold shell, an air passage is formed between the outer and inner mold shells. The refrigeration unit continuously delivers cooling gas between the outer and inner mold shells, which then flows out through the air passage, uniformly cooling the inner mold shell and improving the molding quality of the plastic product.

[0011] Preferably, a heat exchange component is provided on the inner wall of the outer mold shell. The heat exchange component includes a heat absorption part and a heat insulation part. A drive component is provided on the outer mold shell to drive the heat exchange component to rotate. During blow molding, the heat absorption part contacts the inner mold shell, and during cooling, the heat insulation part faces the inner mold shell.

[0012] During cooling, the heat insulation section reduces the consumption of cooling gas by the outer mold shell, allowing most of the cooling gas to be used to cool the inner mold shell, thus accelerating the cooling efficiency of the inner mold shell. Since the heat-absorbing section is located on the side away from the inner mold shell during cooling, it dissipates heat more slowly. Before removing the molded plastic product from the inner mold shell for the next blow molding, the heat-absorbing section comes into contact with the inner mold shell and transfers its remaining heat to the inner mold shell, preheating it and preventing the plastic preform from solidifying rapidly due to a sudden drop in temperature upon contact with the inner mold shell, which could lead to insufficient blowing.

[0013] Preferably, the vertical distance from the heat exchange component to the central axis of the inner mold shell is greater than the vertical distance from the end of the channel facing the inner wall of the outer mold shell to the central axis of the inner mold shell.

[0014] Preferably, the heat exchange assembly includes heat exchange tubes arranged along the inner circumference of the outer mold shell. The heat exchange tubes extend vertically and are rotatably connected to the outer mold shell. A heat insulation plate is provided inside the heat exchange tubes. The heat insulation plate divides the interior of the heat exchange tubes into a heat absorption space and a heat insulation space. The heat absorption space and the portion of the heat exchange tubes corresponding to the heat absorption space form a heat absorption section. The heat insulation space is in a vacuum state. The heat insulation space and the portion of the heat exchange tubes corresponding to the heat insulation space form a heat insulation section.

[0015] By setting the heat exchange components as heat exchange tubes, it is convenient to quickly switch the positions of the insulation part and the heat absorption part.

[0016] Preferably, the driving component three includes a motor, a gear one rotatably connected to the outer mold shell, a gear two fixedly connected to the heat exchange tube, and an arc-shaped rack slidably connected to the outer mold shell. The arc-shaped rack meshes with gear one and gear two respectively. The motor drives gear one to rotate, gear one drives the arc-shaped rack to move, and the arc-shaped rack drives gear two and the corresponding heat exchange tube to rotate.

[0017] Preferably, the outer mold shell is provided with a striking rod and a driving component four for driving the striking rod to strike the inner mold shell.

[0018] Preferably, the striking rod extends vertically and is elastically connected to the outer mold shell in the horizontal direction. The driving component four includes a spur rack and an incomplete gear. The spur rack is fixedly connected to the striking rod, and the incomplete gear is fixedly connected to the heat exchange tube. The incomplete gear meshes with the spur rack. When the heat exchange tube rotates, the incomplete gear drives the spur rack to move the striking rod in the horizontal direction, so that the striking rod repeatedly strikes the inner mold shell.

[0019] During the demolding process of plastic products, sticking and difficulty in demolding are common problems. This may require production staff to manually demold the finished product, increasing their workload and affecting production efficiency. This invention addresses these issues by incorporating a striking rod. When both the outer and inner mold shells are closed, the spring is compressed, pressing the striking rod against the inner mold shell. At this time, the incomplete gear on the heat exchange tube is disengaged from the rack. When the two outer mold shells open to the left and right to a preset position, the motor drives the heat exchange tube to rotate, rotating the heat insulation part towards the inner mold shell. During the rotation of the heat exchange tube, the incomplete gear on the heat exchange tube drives the rack to move the striking rod away from the inner mold shell. When the incomplete gear disengages from the rack, the spring force drives the striking rod towards the inner mold shell, causing it to strike the inner mold shell and thus facilitating the smooth demolding of the plastic product.

[0020] Preferably, the driving component includes two hydraulic telescopic cylinders and two mounting boxes. The mounting boxes are slidably connected to the machine body. The hydraulic telescopic cylinders are fixedly installed on the machine body, and the driving end of the hydraulic telescopic cylinders is fixedly connected to the corresponding mounting box. The outer mold shell is fixedly installed on the corresponding mounting box. The hydraulic telescopic cylinders drive the two mounting boxes to open and close the two outer mold shells.

[0021] Installing the outer mold shell onto the mounting box helps improve the stability of the outer mold shell during its movement.

[0022] Preferably, the driving component two includes two hydraulic telescopic cylinders two, which are fixedly installed in the corresponding mounting box, and the driving end of the hydraulic telescopic cylinder two passes through the corresponding outer mold shell and is fixedly connected to the corresponding inner mold shell.

[0023] Preferably, a refrigeration unit is installed inside the installation box, and a cold air receiving box is installed on the top of the outer mold shell. The cold air receiving box is connected to the refrigeration unit through a gas supply pipe. Multiple channels are opened on the top of the outer mold shell, and the channels are respectively connected to the cold air receiving box.

[0024] By setting up a cold air containment box and multiple channels for cold air to pass through, a large amount of cooling gas can quickly flow between the inner and outer mold shells when the outer mold shell is pulled apart from the inner mold shell, thereby improving the cooling effect on the inner mold shell.

[0025] The beneficial effects of this invention are as follows: By setting the blow molding mold as a double-layer mold composed of an outer mold shell and an inner mold shell, during the blow molding of the tubular plastic preform, the two outer mold shells are driven to move away from each other, creating a brief negative pressure between the outer and inner mold shells. This allows cooling gas to be quickly filled between the outer and inner mold shells, cooling the inner mold shell. This improves upon the problem of uneven cooling of the inner mold shell caused by the inability of the coolant to immediately fill all the cooling pipes during the blow molding of the plastic preform when using cooling pipes. Furthermore, after the outer mold shell is pulled apart to the left and right sides from the outside of the inner mold shell, an air passage is formed between the outer and inner mold shells. The refrigeration unit continuously delivers cooling gas between the outer and inner mold shells, which then flows out from the air passage, uniformly cooling the inner mold shell and improving the molding quality of the plastic product. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the overall structure of a forming device for producing bushing tubes according to the present invention.

[0027] Figure 2 This is a cross-sectional view of a partial structure of a forming device for producing bushings according to the present invention.

[0028] Figure 3 This is a schematic diagram of the structure of the outer mold shell of the forming device for producing bushing tubes according to the present invention when it is opened to both sides.

[0029] Figure 4 This is a schematic diagram of the outer mold shell of a forming device for producing bushing tubes according to the present invention.

[0030] Figure 5 This is a cross-sectional view of the outer mold shell and inner mold shell of a forming device for producing bushing tubes according to the present invention when they are bonded together.

[0031] Figure 6 This is a cross-sectional view of a portion of the outer mold shell of a forming apparatus for producing bushings according to the present invention.

[0032] Figure 7 This is a cross-sectional view of the outer mold shell of a forming apparatus for producing bushings according to the present invention.

[0033] Figure label:

[0034] 1. Machine body; 2. Extrusion device; 3. Air blowing device; 4. Controller; 5. Outer mold shell; 51. Hydraulic telescopic cylinder one; 52. Mounting box; 53. Cold air receiving box; 54. Channel; 55. Air supply pipe; 6. Inner mold shell; 61. Hydraulic telescopic cylinder two; 7. Heat exchange tube; 71. Heat absorption part; 72. Heat insulation part; 73. Heat insulation plate; 74. Motor; 75. Gear one; 76. Gear two; 77. Arc rack; 78. Incomplete gear; 8. Striking rod; 9. Straight rack; 10. Pull rod; 101. Hydraulic telescopic cylinder three. Detailed Implementation

[0035] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0036] like Figures 1 to 7 As shown, a molding apparatus for producing bushing tubes according to the present invention includes a machine body 1, an extrusion device 2, an air blowing device 3, a blow molding die, and a controller 4 disposed on the machine body 1. The extrusion device 2 is used to heat and extrude plastic raw materials into tubular plastic preforms. The tubular plastic preforms fall between the blow molding dies and are clamped by the blow molding dies. A cutting blade (not shown in the figure) is disposed below the extrusion device 2 to separate the tubular plastic preforms clamped between the blow molding dies from the plastic raw materials in the extrusion device 2. The air blowing device 3 is used to blow compressed air into the tubular plastic preforms, causing them to expand and adhere tightly to the inner wall of the blow molding die to form a plastic product. The blowing device 3 has symmetrically arranged pull rods 10 and hydraulic telescopic cylinders 101 that drive the pull rods 10 to move back and forth. When the tubular plastic preform descends to the outer periphery of the pull rods 10, the hydraulic telescopic cylinders 101 drive the two pull rods 10 to move away from each other. The two pull rods 10 pull the lower end of the tubular plastic preform to the front and rear sides, so that the tubular plastic preform can maintain the flatness of the interface when it is clamped by the blow molding die. Since the extrusion device 2 and the blowing device 3 are existing technologies, their specific structures will not be described in detail here.

[0037] The blow molding mold includes an outer mold assembly and an inner mold assembly set within the outer mold assembly. The outer mold assembly includes two outer mold shells 5 arranged symmetrically on the left and right, and the inner mold assembly includes two inner mold shells 6 arranged symmetrically on the left and right. The two inner mold shells 6 are respectively set within the corresponding outer mold shells 5 and are fitted to the corresponding outer mold shells 5.

[0038] The machine body 1 is equipped with a first driving component for opening and closing two outer mold shells 5 and a second driving component for opening and closing two inner mold shells 6. The first driving component includes two hydraulic telescopic cylinders 51 and two mounting boxes 52. The mounting boxes 52 are slidably connected to the machine body 1. The first hydraulic telescopic cylinders 51 are fixedly installed on the machine body 1, and their driving ends are fixedly connected to the corresponding mounting boxes 52. The outer mold shells 5 are fixedly installed on their respective mounting boxes 52. The first hydraulic telescopic cylinders 51 drive the two mounting boxes 52, causing the two outer mold shells 5 to open and close. The second driving component includes two hydraulic telescopic cylinders 61, which are fixedly installed inside their respective mounting boxes 52. The driving ends of the second hydraulic telescopic cylinders 61 penetrate the corresponding outer mold shell 5 and are fixedly connected to the corresponding inner mold shell 6.

[0039] like Figures 1 to 4As shown, a refrigeration unit (not shown in the figure) is installed inside the installation box 52, and a cold air receiving box 53 is installed on the top of the outer mold shell 5. The cold air receiving box 53 is connected to the refrigeration unit through the air supply pipe 55. Multiple channels 54 are opened on the top of the outer mold shell 5, and the channels 54 are respectively connected to the cold air receiving box 53. During the blow molding of the tubular plastic preform, the controller 4 immediately controls the hydraulic telescopic cylinder 51 to drive the two mounting boxes 52 to move the two outer mold shells 5 away from each other. A negative pressure will be briefly formed between the outer mold shell 5 and the inner mold shell 6. Cooling gas will quickly fill the space between the outer mold shell 5 and the inner mold shell 6 from the channel 54 to cool the inner mold shell 6. This improves the problem that when using cooling pipes, the coolant cannot immediately fill all the cooling pipes during the blow molding of the plastic preform, resulting in uneven cooling of the inner mold shell 6. Moreover, after the outer mold shell 5 is pulled apart to the left and right sides from the outside of the inner mold shell 6, an air passage will be formed between the outer mold shell 5 and the inner mold shell. The chiller continuously delivers cooling gas to the space between the outer mold shell 5 and the inner mold shell 6 and flows out from the air passage to uniformly cool the inner mold shell, thus improving the molding quality of the bushing tube.

[0040] To further accelerate the cooling of the inner mold shell and enable rapid molding of plastic products, a heat exchange component is provided on the inner wall of the outer mold shell 5 in this embodiment. The vertical distance from the heat exchange component to the central axis of the inner mold shell 6 is greater than the vertical distance from the end of the channel 54 facing the inner wall of the outer mold shell 5 to the central axis of the inner mold shell 6. That is, after the two outer mold shells 5 are opened to the left and right, the end of the channel 54 facing the inner wall of the outer mold shell 5 is located between the heat exchange component and the inner mold shell 6, and the cooling gas enters between the heat exchange component and the inner mold shell 6 from the channel 54.

[0041] like Figure 4 and Figure 5 As shown, the heat exchange assembly includes a heat absorption part 71 and a heat insulation part 72. The outer mold shell 5 is provided with a driving component 3 for driving the heat exchange assembly to rotate. During cooling, the heat insulation part 72 faces the inner mold shell 6. After the two outer mold shells 5 are pulled apart to both sides, a space for cooling gas to enter is formed between the heat insulation part 72 and the inner mold shell 6. The cooling gas flows from the air passage to exchange heat and cool the inner mold shell 6, thereby accelerating the cooling efficiency of the inner mold shell 6. During blow molding, the heat-absorbing part 71 contacts the inner mold shell 6 and absorbs some of the heat from the inner mold shell 6. Since the heat-absorbing part 71 is located on the side away from the inner mold shell 6 during cooling, the heat-absorbing part 71 dissipates heat more slowly. Before removing the molded plastic product from the inner mold shell 6 for the next blow molding, the heat-absorbing part 71 contacts the inner mold shell 6 and transfers the remaining heat to the inner mold shell 6 to preheat the inner mold shell 6. This prevents the plastic preform from solidifying rapidly due to a sudden drop in temperature when it contacts the inner mold shell 6, which would lead to insufficient blowing. This maintains the softness and plasticity of the plastic preform during the blow molding process, which is beneficial for subsequent blowing and molding.

[0042] The heat exchange assembly includes heat exchange tubes 7 arranged along the inner circumference of the outer mold shell 5. The heat exchange tubes 7 extend vertically and are rotatably connected to the outer mold shell 5. A heat insulation plate 73 is provided inside the heat exchange tubes 7. The heat insulation plate 73 divides the interior of the heat exchange tubes 7 into a heat absorption space and a heat insulation space. The heat absorption space and the part of the heat exchange tubes 7 corresponding to the heat absorption space form a heat absorption part 71. The heat insulation space is in a vacuum state. The heat insulation space and the part of the heat exchange tubes 7 corresponding to the heat insulation space form a heat insulation part 72.

[0043] like Figures 5 to 7 As shown, the driving component three includes a motor 74, a gear 75 rotatably connected inside the outer mold shell 5, a gear 76 fixedly connected to the heat exchange tube 7, and an arc-shaped rack 77 slidably connected inside the outer mold shell 5. The arc-shaped rack 77 meshes with gears 75 and 76 respectively. The motor 74 drives gear 75 to rotate, gear 75 drives the arc-shaped rack 77 to move, and the arc-shaped rack 77 drives gear 76 and the corresponding heat exchange tube 7 to rotate, thereby realizing the switching of the positions of the heat insulation part 72 and the heat absorption part 71.

[0044] During the demolding process of plastic products, sticking and difficulty in demolding can easily occur, potentially requiring production staff to manually demold the finished product, increasing their labor intensity and affecting production efficiency. In this embodiment, a striking rod 8 and a driving component four for driving the striking rod 8 to strike the inner mold shell 6 are provided inside the outer mold shell 5. The striking rod 8 extends vertically and is elastically connected to the outer mold shell 5 in the horizontal direction via a spring (not shown in the figure). The driving component four includes a spur rack 9 and an incomplete gear 78. The spur rack 9 is fixedly connected to the striking rod 8, and the incomplete gear 78 is fixedly connected to the heat exchange tube 7. In this embodiment, the incomplete gear 78 and the gear 76 on the heat exchange tube 7 are integrally formed.

[0045] When both the outer mold shell 5 and the inner mold shell 6 are closed, the spring is compressed and presses the striking rod 8 against the inner mold shell 6. At this time, the incomplete gear 78 on the heat exchange tube 7 is disengaged from the rack 9. When the two outer mold shells 5 open to the left and right to the preset positions, the motor 74 drives the heat exchange tube 7 to rotate, rotating the heat insulation part 72 to the position facing the inner mold shell 6. During the rotation of the heat exchange tube 7, the incomplete gear 78 on the heat exchange tube 7 drives the rack 9 to move the striking rod 8 away from the inner mold shell 6. When the incomplete gear 78 is disengaged from the rack 9, the spring force drives the striking rod 8 to move towards the inner mold shell 6, so that the striking rod 8 strikes the inner mold shell 6, which is conducive to the smooth demolding of plastic products.

[0046] The specific working process of a molding device for producing bushing tubes according to the present invention is as follows: the extrusion device 2 heats and extrudes the plastic raw material into a tubular plastic preform. The tubular plastic preform gradually falls between the blow molding molds. When the tubular plastic preform descends to the outer periphery of the pull rod 10, the hydraulic telescopic cylinder 3 101 drives the two pull rods 10 to move away from each other. The two pull rods 10 pull the lower end of the tubular plastic preform to the front and back sides. The hydraulic telescopic cylinder 1 51 and the hydraulic telescopic cylinder 2 61 are controlled to move synchronously, so that the outer mold shell 5 and the inner mold shell 6 move towards the middle and merge synchronously to clamp the tubular plastic preform. At the same time, the cutting blade cuts off the tubular plastic preform above the blow molding mold. The air blowing device 3 blows compressed air into the tubular plastic preform between the blow molding molds, so that it expands and sticks tightly to the inner wall of the blow molding mold.

[0047] The hydraulic telescopic cylinder 51 drives the two outer mold shells 5 to open to both sides. Cooling gas is quickly filled from the channel 54 into the space between the outer mold shell 5 and the inner mold shell 6, and flows out from the air passage between the outer mold shell 5 and the inner mold shell, quickly and evenly cooling the inner mold shell.

[0048] After the outer mold shell 5 moves to the preset position, the control motor 74 drives the heat exchange tube 7 to rotate, so that the heat insulation part 72 rotates to the position facing the inner mold shell 6 and the heat absorption part 71 rotates to the position away from the inner mold shell 6. During the rotation of the heat exchange tube 7, the incomplete gear 78 on the heat exchange tube 7 drives the rack 9 to move the striking rod 8 away from the inner mold shell 6. When the incomplete gear 78 disengages from the rack 9, the spring force drives the striking rod 8 to move towards the inner mold shell 6, so that the striking rod 8 strikes the inner mold shell 6.

[0049] After cooling is complete, the hydraulic telescopic cylinder 51 drives the two outer mold shells 5 to continue moving to both sides, causing the striking rod 8 to disengage from the inner mold shell 6. Then, the motor 74 drives the heat exchange tube 7 to rotate in the opposite direction, causing the heat insulation part 72 to rotate away from the inner mold shell 6 and the heat absorption part 71 to rotate towards the inner mold shell 6. During the rotation of the heat exchange tube 7, the incomplete gear 78 drives the rack 9 to move the striking rod 8 closer to the inner mold shell 6. When the striking rod 8 strikes the inner mold shell 6, the incomplete gear 78 disengages from the rack 9, and the striking rod 8 disengages from the inner mold shell 6 under the action of the spring.

[0050] Then, the hydraulic telescopic cylinder 261 is controlled to drive the two inner mold shells 6 to open to the left and right sides, so that the plastic product can be demolded and taken out.

[0051] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0052] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0053] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A molding apparatus for producing bushings, comprising a machine body, an extrusion device, an air blowing device, a blow molding die, and a controller mounted on the machine body, characterized in that, The blow molding mold includes an outer mold assembly and an inner mold assembly set within the outer mold assembly. The outer mold assembly includes two symmetrically arranged outer mold shells, and the inner mold assembly includes two symmetrically arranged inner mold shells. The two inner mold shells are respectively set within the corresponding outer mold shells and fit against the corresponding outer mold shells. The outer mold shells are provided with channels for conveying cooling gas. The machine body is equipped with a drive component 1 for opening and closing two outer mold shells and a drive component 2 for opening and closing two inner mold shells. When cooling is required, the controller controls the drive component 1 to drive the two outer mold shells to move away from each other, creating a negative pressure between the outer and inner mold shells. Cooling gas is then quickly filled between the outer and inner mold shells through the channel to cool the inner mold shells. A heat exchange assembly is provided on the inner wall of the outer mold shell. The heat exchange assembly includes a heat absorption part and a heat insulation part. A drive component is provided on the outer mold shell to drive the heat exchange assembly to rotate. During blow molding, the heat absorption part contacts the inner mold shell, and during cooling, the heat insulation part faces the inner mold shell. The vertical distance from the heat exchange component to the central axis of the inner mold shell is greater than the vertical distance from the end of the channel facing the inner wall of the outer mold shell to the central axis of the inner mold shell. The heat exchange assembly includes heat exchange tubes arranged along the inner circumference of the outer mold shell. The heat exchange tubes extend vertically and are rotatably connected to the outer mold shell. A heat insulation plate is installed inside the heat exchange tubes. The heat insulation plate divides the inside of the heat exchange tubes into a heat absorption space and a heat insulation space. The heat absorption space and the part of the heat exchange tubes corresponding to the heat absorption space form the heat absorption part. The heat insulation space is in a vacuum state. The heat insulation space and the part of the heat exchange tubes corresponding to the heat insulation space form the heat insulation part. The driving component three includes a motor, a gear one rotatably connected to the outer mold shell, a gear two fixedly connected to the heat exchange tube, and an arc-shaped rack slidably connected to the outer mold shell. The arc-shaped rack meshes with gear one and gear two respectively. The motor drives gear one to rotate, gear one drives the arc-shaped rack to move, and the arc-shaped rack drives gear two and the corresponding heat exchange tube to rotate.

2. The forming apparatus for bushing production according to claim 1, characterized in that, The outer mold shell is equipped with a striking rod and a driving component four that drives the striking rod to strike the inner mold shell.

3. The forming apparatus for bushing production according to claim 2, characterized in that, The striking rod extends vertically and is elastically connected to the outer mold shell in the horizontal direction. The driving component four includes a spur rack and an incomplete gear. The spur rack is fixedly connected to the striking rod, and the incomplete gear is fixedly connected to the heat exchange tube. The incomplete gear meshes with the spur rack. When the heat exchange tube rotates, the incomplete gear drives the spur rack to move the striking rod in the horizontal direction so that the striking rod repeatedly strikes the inner mold shell.

4. The forming apparatus for bushing production according to claim 1, characterized in that, The drive unit includes two hydraulic telescopic cylinders and two mounting boxes. The mounting boxes are slidably connected to the machine body. The hydraulic telescopic cylinders are fixedly installed on the machine body, and the drive end of the hydraulic telescopic cylinders is fixedly connected to the corresponding mounting box. The outer mold shell is fixedly installed on the corresponding mounting box. The hydraulic telescopic cylinders drive the two mounting boxes to open and close the two outer mold shells.

5. The forming apparatus for bushing production according to claim 4, characterized in that, The second driving component includes two hydraulic telescopic cylinders, which are fixedly installed in the corresponding mounting boxes, and the driving end of the second hydraulic telescopic cylinder passes through the corresponding outer mold shell and is fixedly connected to the corresponding inner mold shell.

6. The forming apparatus for bushing production according to claim 4, characterized in that, The installation box contains a refrigeration unit, and the top of the outer mold shell has a cold air receiving box. The cold air receiving box is connected to the refrigeration unit through a gas supply pipe. The top of the outer mold shell has multiple channels, which are connected to the cold air receiving box.

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