A plastic mold for producing PET plastic cups

Abstract

The present invention relates to the field of PET injection molding technology, specifically a plastic mold for producing PET plastic cups, comprising a frame, a conveyor belt is arranged at the lower side of the frame; a movable mold, four clamping cylinders are fixedly installed on the top of the frame, a movable mold is fixedly installed on the output end of the clamping cylinder, a material pipe is fixedly installed on the top of the movable mold, and the material pipe passes through the top of the frame; a fixed mold, a fixed mold that cooperates with the movable mold is arranged in the middle of the frame, and a mold cavity for cooperating with the movable mold is opened on the upper and lower surfaces of the fixed mold; a short rotating shaft and a long rotating shaft are fixedly installed on the left and right sides of the fixed mold, respectively, and the short rotating shaft and the long rotating shaft are both horizontally rotated and installed on the frame, and a right-angle motor is installed at one end of the long rotating shaft. The present invention solves the problem that the existing equipment needs a robot to unload the material by setting a rotatable double-sided fixed mold, and the robot is used to stably place the blank on the conveyor belt before it can be transferred to the next station for processing.

Description

Technical Field

[0001] The invention relates to the technical field of PET injection molding, in particular to a plastic mold for producing PET plastic cups. Background Art

[0002] PET is a milky white or light yellow highly crystalline polymer with a smooth and shiny surface. It has good creep resistance, fatigue resistance, abrasion resistance and dimensional stability, low wear and high hardness, and has the greatest toughness among thermoplastics: good electrical insulation performance, little temperature influence, but poor corona resistance. It is non-toxic, weather-resistant, and has good chemical resistance stability, low water absorption, and is resistant to weak acids and organic solvents, but not hot water immersion and alkali. Plastic bottles produced by PET are widely used to package carbonated beverages, drinking water, fruit juice, enzymes and tea beverages. At the same time, PET can also be used to produce plastic cups.

[0003] The production of PET plastic cups can be produced by stamping, vacuum forming, or injection molding. The existing production of PET plastic cups is partly by first injecting a rough blank of the plastic cup in an injection mold. When unloading, the rough blank is removed by a robot and placed upside down on a conveyor belt. The rough blank is sent to be heated via the conveyor belt, and then blow-molded through a blow mold to obtain a long strip of water cup like a thermos cup.

[0004] For the production of the above-mentioned PET plastic cups, during the process of the robot taking off the rough blanks of the PET plastic cups, the injection molding production of the next batch of rough blanks cannot be carried out, and the production efficiency is low. At the same time, if the robot is used to take the material, although the rough blanks can be placed upside down on the conveyor belt, the production cost is also increased.

[0005] For this reason, a plastic mold for producing a PET plastic cup is proposed. Summary of the invention

[0006] The object of the present invention is to provide a plastic mold for producing PET plastic cups, which solves the problems raised in the above-mentioned background technology by arranging a male mold that can move up and down for mold closing, a reversible double-sided female mold and a two-way ejection mechanism.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] A frame, wherein a conveyor belt for conveying rough plastic cups is provided at the lower side of the frame;

[0009] A movable mold, four pressing cylinders are fixed vertically downward on the top of the frame, a movable mold is fixedly installed on the output ends of the pressing cylinders, a material pipe is fixedly installed on the top of the movable mold, and the material pipe passes through the top of the frame;

[0010] A fixed mold is provided in the middle of the frame and cooperates with the movable mold, and the fixed mold is located between the conveyor belt and the movable mold. The upper and lower surfaces of the fixed mold are provided with mold cavities for cooperating with the movable mold;

[0011] A short rotating shaft and a long rotating shaft are fixedly installed on the left and right sides of the fixed mold respectively. The short rotating shaft and the long rotating shaft are both installed on the frame for horizontal rotation. Bearings are installed between the long rotating shaft, the short rotating shaft and the frame. The right-angle motor is fixed on the outside of the frame. The end of the long rotating shaft away from the fixed mold is connected to the right-angle motor. A two-way ejection mechanism is arranged inside the fixed mold.

[0012] Preferably, the fixed die is a concave die, and the movable die is a convex die that cooperates with the fixed die.

[0013] Preferably, the bidirectional ejection mechanism includes two circular holes penetrating the fixed mold, and the two circular holes are symmetrical about the two mold cavities. A rectangular groove is horizontally opened in the middle of the fixed mold, and the rectangular groove connects the two circular holes. Circular spring grooves are opened in the middle of the rectangular groove, and through holes for connecting the rectangular groove with the upper and lower mold cavities are opened in the middle of the upper and lower spring grooves. Slide rods are slidably installed in the middle of the two through holes. The two slide rods extend into the interior of the rectangular groove from the upper and lower mold cavities respectively, and one end of the two slide rods in the mold cavity is fixedly installed with Push plate, the bottom of the two mold cavities are provided with grooves for cooperating with the push plates, and one end of the two slide rods in the rectangular grooves are fixedly installed with limit plates, and springs are evenly wound around the two slide rods, one end of the two springs are respectively fixed on the bottom of the upper and lower spring grooves, and the other ends are respectively fixedly installed on the two limit plates, a cross plate is horizontally arranged in the middle of the rectangular groove, the cross plate is located between the two limit plates, and round rods are fixedly installed on the left and right sides of the upper and lower surfaces of the cross plate, and the four round rods can slide up and down in the two round holes.

[0014] Preferably, one end of the four round rods away from the rectangular groove extends out of the upper and lower surfaces of the fixed mold respectively when not in operation.

[0015] Preferably, ball grooves are provided around the middle parts of the four round rods, and balls are arranged in the ball grooves.

[0016] Preferably, a preheating device is installed around the two mold cavities, and a round piece is fixedly installed on one end of the four round rods extending out of the fixed mold. The upper and lower surfaces of the fixed mold are provided with circular grooves for cooperating with the four round pieces. Switches are installed at the bottom of the circular grooves on the right sides of the upper and lower surfaces, and the switches are electrically connected to the preheating device.

[0017] Preferably, the frame also includes a supporting device, which includes a supporting plate that spans the conveyor belt and is horizontally arranged between the conveyor belt and the fixed mold, the supporting plate is made of steel and has a thickness of 20 mm or more, and supporting cylinders are arranged on the left and right sides of the lower surface of the support plate, the output ends of the two supporting cylinders are arranged vertically upward, the output ends of the two supporting cylinders are fixed to the lower surface of the support plate, and the two supporting cylinders are installed on the frame on the side opposite to the conveying direction of the conveyor belt.

[0018] Preferably, a hard rubber block is fixedly mounted on the upper surface of the support plate.

[0019] Preferably, a code disc is fixedly mounted on the long rotating shaft, and the code disc is located between the fixed mold and the frame. The code disc is a metal disc, and two notches are formed on the code disc, and the two notches are evenly distributed on the code disc at 180°. The frame is located on one side of the long rotating shaft and a mounting plate is horizontally fixedly mounted thereon, and the mounting plate is aligned with the long rotating shaft. A proximity switch is fixedly mounted on the mounting plate, and the proximity switch is aligned with the code disc, and the proximity switch is electrically connected to the right-angle motor.

[0020] Preferably, four limit holes are provided at the position where the long rotating shaft and the frame are installed, the four limit holes are evenly arranged on the long rotating shaft, and the four limit holes are all on the same vertical plane, steel balls are provided inside the four limit holes, and spring 2 is provided between the four steel balls and the bottom of the limit holes, and four spherical slots for cooperating with the limit holes are provided on the frame.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] 1. Compared with the prior art, the plastic mold for producing PET plastic cups described in the present invention solves the problem of requiring a robot to unload the plastic cups by providing a convex mold that can move up and down for mold closing, a reversible double-sided concave mold and a two-way ejection mechanism. At the same time, it also solves the problem that injection molding cannot be performed during the unloading process, thereby eliminating the need for a robot, reducing the use cost and improving production efficiency.

[0023] 2. The plastic mold for producing PET plastic cups described in the present invention utilizes mold closing pressure to unload materials, and does not require an additional power source for unloading, thereby reducing the use cost.

[0024] 3. The plastic mold for producing PET plastic cups described in the present invention controls the rotation angle through a code disk and a proximity switch, and performs limit compensation through a spring, a steel ball and a spherical slot, thereby preventing the fixed mold from having a deviation in the rotation angle, resulting in insufficient matching accuracy between the fixed mold and the movable mold when the mold is closed, causing collisions between the molds and the plastic cups failing to meet the requirements, thereby improving the life of the equipment and production stability.

[0025] 4. The plastic mold for producing PET plastic cups described in the present invention cooperates with the support plate through the cylinder to provide an upward supporting force to the mold when the mold is closed, thereby reducing the force on the rotating shaft when the mold is closed, increasing the life of the rotating shaft, preventing the produced plastic cups from failing to meet the use requirements due to the bending of the rotating shaft when the mold is closed, and improving the production stability of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is a side view of the present invention;

[0027] Figure 2 It is a front view of the mold clamping state of the present invention;

[0028] Figure 3 For the present invention Figure 2 A cross-sectional view of the partial view A;

[0029] Figure 4 For the present invention Figure 3 A partial enlarged view of B in the middle;

[0030] Figure 5 It is a schematic diagram of the installation structure of the code disk and the proximity switch of the present invention;

[0031] Figure 6 It is a schematic diagram of the matching structure of the steel ball and the spherical slot of the present invention.

[0032] In the figure: 1. frame; 2. conveyor belt; 3. movable mold; 4. clamping cylinder; 5. material pipe; 6. fixed mold; 7. short rotating shaft; 8. long rotating shaft; 9. bearing; 10. right-angle motor; 11. mold cavity; 12. round hole; 13. rectangular groove; 14. spring groove; 15. through hole; 16. slide bar; 17. push plate; 18. limit plate; 19. spring one; 20. groove; 21. horizontal plate; 22. round rod; 23. ball groove; 24. ball; 25. preheating device; 26. disc; 27. round groove; 28. switch; 29. ​​support plate; 30. support cylinder; 31. hard rubber block; 32. code disk; 33. notch; 34. mounting plate; 35. proximity switch; 36. limit hole; 37. steel ball; 38. spring two; 39. spherical slot. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicating directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as limiting the present invention.

[0035] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "multiple" means two or more, unless otherwise clearly and specifically defined. In addition, the terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0036] See also Figures 1 to 6 The present invention provides a plastic mold for producing PET plastic cups, and the technical solution is as follows:

[0037] A plastic mold for producing PET plastic cups, comprising a frame 1, a conveyor belt 2 for conveying rough plastic cups is arranged at the lower side of the frame 1; a movable mold 3, four pressing cylinders 4 are fixed vertically downward on the top of the frame 1, and a movable mold 3 is fixedly installed on the output end of the pressing cylinder 4, a material pipe 5 is fixedly installed on the top of the movable mold 3, and the material pipe 5 passes through the top of the frame 1; a fixed mold 6, a fixed mold 6 that cooperates with the movable mold 3 is arranged in the middle of the frame 1, and the fixed mold 6 is located between the conveyor belt 2 and the movable mold 3. The fixed mold 6 has a mold cavity 11 on both the upper and lower surfaces for cooperating with the movable mold 3; the fixed mold 6 has a short rotating shaft 7 and a long rotating shaft 8 fixedly installed on the left and right sides respectively, the short rotating shaft 7 and the long rotating shaft 8 are both horizontally rotatably installed on the frame 1, and bearings 9 are installed between the long rotating shaft 8 and the short rotating shaft 7 and the frame 1, the right-angle motor 10 is fixed on the outside of the frame 1, and the end of the long rotating shaft 8 away from the fixed mold 6 is connected to the right-angle motor 10, and a two-way ejection mechanism is arranged inside the fixed mold 6.

[0038] The movable mold 3, the fixed mold 6 and the conveyor belt 2 for conveying the rough blank of the plastic cup are installed through the frame 1. The movable mold 3 is installed on the upper side of the frame 1, and the fixed mold 6 is rotatably installed in the middle part of the frame 1 through the short rotating shaft 7 and the long rotating shaft 8 thereon. The conveyor belt 2 is installed on the lower side of the frame 1. The upper surface of the conveyor belt 2 is about 5-10mm higher than the height of the rough blank of the plastic cup from the bottom of the fixed mold 6. At the beginning, the movable mold 3 is driven downward by four clamping cylinders 4 to close the mold with the fixed mold 6. The clamping cylinder 4 is a standard cylinder or other cylinders or devices that can realize linear extension and retraction and meet the use requirements. Then, the material pipe 5 injects molten plastic into the mold cavity 11, and after cooling, a rough plastic cup is obtained. Then, the movable mold 3 is controlled by four clamping cylinders 4 to move upward and return to the initial position. The right-angle motor 10 controls the long rotating shaft 8 to rotate 180°. The right-angle motor 10 is a rodless stepping motor. The long rotating shaft 8 finally controls the fixed mold 6 to rotate 180°. Then the movable mold 3 repeats the above steps again and is molded with another mold cavity 11 of the fixed mold 6 for injection molding. The cooled rough plastic cup is ejected by the two-way ejection mechanism onto the conveyor belt 2. Then, the rough plastic cup is continuously produced in this way. The problem that the original plastic cup injection mold cannot perform injection molding production at the same time during the unloading process is solved, and the production efficiency is improved.

[0039] As an embodiment of the present invention, refer to Figure 3 The fixed die 6 is a concave die, and the movable die 3 is a convex die that cooperates with the fixed die 6.

[0040] After the movable mold 3 and the fixed mold 6 are molded together for injection molding, the rough plastic cup remains inside the fixed mold 6, and then the long rotating shaft 8 is driven by the right-angle motor 10 to rotate 180 degrees, and then the long rotating shaft 8 drives the fixed mold 6 to rotate 180 degrees to open the rough plastic cup downward, and finally the rough plastic cup is ejected downward by the two-way ejection mechanism, and the rough plastic cup falls downward on the conveyor belt 2, and is transported to another station by the conveyor belt 2. This solves the problem that the original plastic cup mold needs a robot to place the rough plastic cup with its opening downward on the conveyor belt 2 after injection molding, thereby reducing production costs.

[0041] As an embodiment of the present invention, refer to Figure 3The bidirectional ejection mechanism includes two circular holes 12 penetrating the fixed mold 6, and the two circular holes 12 are symmetrical about the two mold cavities 11. A rectangular groove 13 is horizontally opened in the middle of the fixed mold 6, and the rectangular groove 13 connects the two circular holes 12. Circular spring grooves 14 are opened in the middle of the rectangular groove 13, and through holes 15 for connecting the rectangular groove 13 with the upper and lower mold cavities 11 are opened in the middle of the upper and lower spring grooves 14. Slide rods 16 are slidably installed in the middle of the two through holes 15. The two slide rods 16 extend into the interior of the rectangular groove 13 from the upper and lower mold cavities 11 respectively, and a push plate is fixedly installed at one end of the two slide rods 16 in the mold cavity 11 17, the bottom of the two mold cavities 11 are provided with grooves 20 for cooperating with the push plates 17, and one end of the two slide bars 16 in the rectangular groove 13 is fixedly installed with a limit plate 18, and the two slide bars 16 are evenly wound with springs 19, one end of the two springs 19 are respectively fixed to the bottom of the upper and lower spring grooves 14, and the other ends are respectively fixedly installed on the two limit plates 18, a cross plate 21 is horizontally arranged in the middle of the rectangular groove 13, the cross plate 21 is located between the two limit plates 18, and round rods 22 are fixedly installed on the left and right sides of the upper and lower surfaces of the cross plate 21, and the four round rods 22 can slide up and down in the two round holes 12.

[0042] When the mold is not closed, the two springs 19 pull the push plates 17 in the upper and lower mold cavities 11 toward the bottom of the mold cavity 11 through elastic force. At the same time, the cross plate 21 inside the rectangular groove 13 is limited by the two limit plates 18 under the elastic force of the two springs 19, and is kept in the middle of the rectangular groove 13 when not working. When a mold cavity 11 is closed for injection molding, the four round rods 22 are controlled to move downward in the round hole 12, and the round rods 22 drive the cross plate 21 to move downward, and a spring 19 located below is compressed and connected to it. A limit plate 18 moves downward and drives the slide bar 16 to slide downward in the through hole 15 below, and finally drives the push plate 17 below to move downward, pushing the rough plastic cup out of the mold cavity 11 below and onto the conveyor belt 2. When the right-angle motor 10 rotates 180°, the fixed mold 6 finally rotates 180°, and the mold cavity 11 originally located above becomes the mold cavity 11 below. Repeating the above steps can complete the continuous unloading of the rough plastic cup, solving the problem that both the upper and lower mold cavities 11 need to be unloaded, thereby improving production continuity and production efficiency.

[0043] As an embodiment of the present invention, refer to Figure 3 When not in operation, the ends of the four round rods 22 away from the rectangular groove 13 extend out of the upper and lower surfaces of the fixed mold 6 respectively.

[0044] When the movable mold 3 is driven by the four clamping cylinders 4 to close the mold downward, the movable mold 3 will push the round rod 22 extending from the upper surface downward, and the round rod 22 slides downward inside the round hole 12, and then drives the cross plate 21 downward, the cross plate 21 pushes the limit plate 18 downward, the limit plate 18 drives the slide bar 16, and finally drives the push plate 17 downward to push the rough plastic cup downward from the mold cavity 11 below to the conveyor belt 2 to complete unloading. When the upper and lower surfaces of the fixed mold 6 alternate, the above steps are repeated to complete unloading. By linking unloading with mold closing and utilizing the pressure during mold closing to unload, there is no need to add an additional power source to the unloading device, which improves energy utilization and reduces the cost increase caused by the use of an additional power source.

[0045] As an embodiment of the present invention, refer to Figure 3 A ball groove 23 is formed around the middle part of the four round rods 22, and balls 24 are arranged in the ball groove 23.

[0046] The ball 24 is made of steel. When the round rod 22 moves up and down, the ball 24 converts the sliding friction between the round rod 22 and the round hole 12 into rolling friction between the ball 24, reducing the wear and heat between the round rod 22 and the round hole 12, and avoiding the problem of damage to the round rod 22 after long-term work. At the same time, adding the ball 24 can also reduce the manufacturing accuracy and matching accuracy of the round hole 12 and the round rod 22, improve the stability of the equipment, and reduce the process cost of the mold.

[0047] As an embodiment of the present invention, refer to Figure 3 A preheating device 25 is installed around the two mold cavities 11, and a disc 26 is fixedly installed on one end of the four round rods 22 extending from the fixed mold 6. The fixed mold 6 has circular grooves 27 on the upper and lower surfaces for cooperating with the four discs 26. Switches 28 are installed at the bottom of the circular grooves 27 on the right sides of the upper and lower surfaces, and the switch 28 is electrically connected to the preheating device 25.

[0048] The above-mentioned preheating device 25 is an infrared heating tube, but is not limited to an infrared heating tube. Other devices that can help the mold to be heated and preheated are also acceptable. When the movable mold 3 is pressed down, the disc 26 on the round rod 22 extending from the upper surface of the fixed mold 6 moves downward, enters the circular groove 27 and presses the switch 28. At this time, the switch 28 inside the upper circular groove 27 controls the preheating device 25 around the lower mold cavity 11 to preheat the mold cavity 11 after the lower discharge, and at this time, the switch 28 in the lower circular groove 27 controls the preheating device 25 around the upper mold cavity 11. Since the switch 28 on the lower side is not The preheating device 25 around the upper mold cavity 11 is under pressure, so the preheating device 25 around the upper mold cavity 11 is not started. When the fixed mold 6 rotates 180° for mold closing and injection molding, the above steps will be repeated. Preheating devices 25 are set around the upper and lower mold cavities 11, and cross-control is performed using the switch 28 to achieve the effect of alternating preheating. While unloading on one side, it is equipped for the next injection molding in advance, thereby improving production efficiency. At the same time, the disc 26 increases the contact area between the round rod 22 and the movable mold 3, reduces the contact pressure concentration between the round rod 22 and the movable mold 3 when the mold is closed, and reduces the wear of the movable mold 3.

[0049] As an embodiment of the present invention, refer to Figure 1 , Figure 2 The frame 1 also includes a supporting device, which includes a supporting plate 29 that spans the conveyor belt 2 and is horizontally arranged between the conveyor belt 2 and the fixed mold 6. The supporting plate 29 is made of steel and has a thickness of 20 mm or more. Support cylinders 30 are arranged on the left and right sides of the lower surface of the support plate 29. The output ends of the two support cylinders 30 are arranged vertically upward. The output ends of the two support cylinders 30 are fixed to the lower surface of the support plate 29, and the two support cylinders 30 are installed on the frame 1 on the side opposite to the conveying direction of the conveyor belt 2.

[0050] The supporting cylinder 30 is a standard cylinder. Other cylinders or various structures and devices that can achieve linear extension and retraction and have a certain supporting effect and meet the use requirements can also be used. When the movable mold 3 and the fixed mold 6 are molded for injection, the two supporting cylinders 30 extend upward at the same time, and the supporting plate 29 is driven upward and fits against the lower surface of the fixed mold 6, giving the fixed mold 6 an upward supporting force. When the injection molding is completed, the two supporting cylinders 30 are retracted at the same time, and the supporting plate 29 moves downward to reset. The setting of the supporting device helps the short rotating shaft 7 and the long rotating shaft 8 share part of the pressure during the mold closing, reduces the deformation of the short rotating shaft 7 and the long rotating shaft 8 caused by the influence of long-term mold closing pressure, and ultimately makes the problem that the rough plastic cup does not meet the production standards, thereby improving the stability of the equipment.

[0051] As an embodiment of the present invention, refer to Figure 1 , Figure 2 A hard rubber block 31 is fixedly mounted on the upper surface of the support plate 29 .

[0052] The hard rubber block 31 can also be replaced by a hard material with low wear on metal, such as plastic. When the support plate 29 supports the fixed mold 6 upward, the original contact between the support plate 29 and the fixed mold 6 is changed to the contact between the hard rubber block 31 and the fixed mold 6, avoiding the wear caused by direct contact between the support plate 29 and the fixed mold 6.

[0053] As an embodiment of the present invention, refer to Figure 2 , Figure 5 A code disc 32 is fixedly installed on the long rotating shaft 8, and the code disc 32 is located between the fixed mold 6 and the frame 1. The code disc 32 is a metal disc, and two notches 33 are opened on the code disc 32. The two notches 33 are evenly distributed on the code disc 32 at 180°. The frame 1 is horizontally fixedly installed with a mounting plate 34 on one side of the long rotating shaft 8. The mounting plate 34 is aligned with the long rotating shaft 8. A proximity switch 35 is fixedly installed on the mounting plate 34. The proximity switch 35 is aligned with the code disc 32, and the proximity switch 35 is electrically connected to the right-angle motor 10.

[0054] The pause time of the right-angle motor 10 is set according to the time required for injection cooling and forming. The proximity switch 35 generates an electrical signal after detecting the gap 33 of the code disk 32. The signal is fed back to the right-angle motor 10, and the right-angle motor 10 pauses, injection molding and cooling are performed, and then the right-angle motor 10 is started. After the proximity switch 35 detects the gap 33 again, the right-angle motor 10 pauses again. This reciprocating process is used to realize the right-angle motor 10 controlling the fixed mold 6 to rotate and flip. This method of controlling the rotation of the right-angle motor 10 has good human-computer timely interaction. There is no need to set a computer to control the right-angle motor 10 and there is no need to set the stepping parameters of the rotation of the right-angle motor 10 in the computer controlling the right-angle motor 10 in advance and then perform complex programming. It is only necessary to control the power on and off of the right-angle motor 10 through the electrical signal generated by the proximity switch 35, thereby reducing the control cost.

[0055] As an embodiment of the present invention, refer to Figure 6 Four limiting holes 36 are provided at the position where the long rotating shaft 8 and the frame 1 are installed. The four limiting holes 36 are evenly arranged on the long rotating shaft 8, and the four limiting holes 36 are all on the same vertical plane. Steel balls 37 are provided inside the four limiting holes 36, and springs 38 are provided between the four steel balls 37 and the bottom of the limiting holes 36. Four spherical slots 39 for cooperating with the limiting holes 36 are provided on the frame 1.

[0056] When the long rotating shaft 8 has a slight deviation after the right-angle motor 10 stops rotating, the steel ball 37 will roll into the spherical slot 39 due to the relationship between the spherical slot 39, and drive the long rotating shaft 8 to rotate. The steel ball 37 entering the spherical slot 39 is pressed tightly in the spherical slot 39 under the action of the spring 2 38, and finally the fixed mold 6 reaches the specified clamping angle. When the right-angle motor 10 rotates, the torque brought by the right-angle motor 10 will force the steel ball 37 to leave the spherical slot 39, and then the steel ball 37 is pressed into the limit hole 36, and the spring 2 38 is also compressed accordingly, which solves the problem of slight deviation in the rotation angle of the fixed mold 6 caused by insufficient control accuracy of the code disk 32 and the proximity switch 35 on the right-angle motor 10, thereby improving the stability of the equipment.

[0057] Working principle: When not working, the four clamping cylinders 4 are in a retracted state, the movable mold 3 is fixed on the output ends of the four clamping cylinders 4, the fixed mold 6 is in a state where one cavity 11 is vertically upward and the other cavity 11 is vertically downward, the two supporting cylinders 30 are also in a retracted state, the supporting plate 29 is fixed on the output ends of the two supporting cylinders 30, the hard rubber block 31 is fixed on the upper surface of the supporting plate 29, and the conveyor belt 2 is in a stationary state. After the injection molding starts, the conveyor belt 2 starts to work, and the four clamping cylinders 4 drive the movable mold 3 to move downward and close the mold with the fixed mold 6. At the same time, the supporting cylinders 30 extend upward, driving the supporting plate 29 and the hard rubber block 31 to press upward against the bottom surface of the fixed mold 6, giving the fixed mold 6 an upward supporting force to share the load borne by the long rotating shaft 8 and the short rotating shaft 7. The movable mold 3 moves upward. When the lower mold is closed, the disc 26 is pushed downward to press the switch 28. The switch 28 controls the preheating device 25 around the lower mold cavity 11 to perform preheating. The first mold closing does not perform injection molding because the upper mold cavity 11 has not been preheated. After reaching the pause time required for injection molding set by the right-angle motor 10, the clamping cylinder 4 drives the movable mold 3 to retract, and the supporting cylinder 30 also drives the supporting plate 29 and the hard rubber block 31 to retract. The right-angle motor 10 starts to rotate, and drives the code disk 32 and the long shaft 8 and the short shaft 7 to rotate, and the fixed mold 6 also rotates accordingly. After rotating 180°, the right-angle motor 10 stops rotating when the proximity switch 35 detects the notch 33 of the code disk 32. If there is a slight deviation that causes the two planes of the fixed mold 6 with the mold cavity 11 to be not aligned, the right-angle motor 10 stops rotating. When the mold is horizontal, the steel ball 37 will roll into the spherical slot 39, thereby driving the long rotating shaft 8 and the short rotating shaft 7 to rotate, and finally adjusting the opening plane of the two mold cavities 11 to be horizontal, and then the clamping cylinder 4 and the supporting cylinder 30 will extend at the same time, the clamping cylinder 4 will drive the movable mold 3 and the fixed mold 6 to close the mold, and the supporting cylinder 30 will drive the supporting plate 29 and the hard rubber block 31 to support the fixed mold 6, and the molten plastic will be injected into the upper mold cavity 11 through the material pipe 5. At the same time, the switch 28 controls the preheating device 25 to preheat the lower mold cavity 11. After the rough plastic cup is cooled, the clamping cylinder 4 will drive the movable mold 3 to retract again, and the supporting cylinder 30 will also drive the supporting plate 29 and the hard rubber block 31 to retract. At this time, the rough plastic cup remains in the upper mold cavity 11 of the fixed mold 6, and the right-angle motor 10 will press the mold according to the code The disk 32 and the proximity switch 35 are controlled to rotate 180° again to swap the positions of the original upper and lower mold cavities 11. At this time, the mold cavity 11 with the rough plastic cup embryo is located in the lower half of the fixed mold 6. When the upper mold cavity 11 is molded again for injection molding, the movable mold 3 pushes the disc 26 downward to press the switch 28 downward to control the preheating device 25 in the lower half to preheat the lower mold cavity 11. At the same time, the disc 26 drives the four round rods 22 to move downward in the round hole 12, and finally drives the cross plate 21 to push the lower limit plate 18 downward. The lower limit plate 18 drives the slide bar 16 to slide downward, and drives the push plate 17 in the lower mold cavity 11 to push the rough plastic cup embryo downward. The opening of the rough plastic cup embryo falls downward on the conveyor belt 2, completing the process of unloading and injection molding at the same time.After the injection molding is completed and before the next injection molding is performed, the two horizontal plates 21 are kept in the middle of the rectangular groove 13 by the action of the two springs 19 and the limit plate 18, and the two push plates 17 are also tightly pulled to the bottom of the two mold cavities 11 by the action of the springs 19, and then the above process is repeated and the production is continuous.

[0058] The electrical components appearing in this article are all connected to the external main controller and 220V AC power through a transformer, and the main controller can be a conventional known device that controls a computer, etc. The product model provided by the present invention is only used for the technical solution according to the structural characteristics of the product. The product will be adjusted and modified after purchase to make it more matching and consistent with the technical solution of the present invention. It is a technical solution for the best application of the technical solution. The model of its product can be replaced and modified according to the required technical parameters, which is well known to technical personnel in this field. Therefore, technical personnel in this field can clearly obtain the corresponding use effect through the technical solution provided by the present invention.

[0059] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A plastic mold for producing PET plastic cups, include: A frame (1), wherein a conveyor belt (2) for conveying plastic cup rough blanks is arranged at the lower side of the frame (1); a movable mold (3), wherein four pressing cylinders (4) are fixed vertically downward on the top of the frame (1), and a movable mold (3) is fixedly installed on the output ends of the four pressing cylinders (4), and a material pipe (5) is fixedly installed on the top of the movable mold (3), and the material pipe (5) passes through the top of the frame (1); a fixed mold (6), wherein a fixed mold (6) cooperating with the movable mold (3) is arranged in the middle of the frame (1), and the fixed mold (6) is located between the conveyor belt (2) and the movable mold (3), and the fixed mold (6) both upper and lower surfaces are provided with mold cavities (11) for cooperating with the movable mold (3); the characteristics are as follows: a short rotating shaft (7) and a long rotating shaft (8) are respectively fixedly installed on the left and right sides of the fixed mold (6); the short rotating shaft (7) and the long rotating shaft (8) are both horizontally rotatably installed on the frame (1); bearings (9) are installed between the long rotating shaft (8) and the short rotating shaft (7) and the frame (1); a right-angle motor (10) is fixed on the outside of the frame (1); one end of the long rotating shaft (8) away from the fixed mold (6) is fixedly connected to the output end of the right-angle motor (10); and a two-way ejection mechanism is arranged inside the fixed mold (6); The fixed die (6) is a concave die, and the movable die (3) is a convex die that cooperates with the fixed die (6); The bidirectional ejection mechanism comprises two circular holes (12) penetrating the fixed mold (6), and the two circular holes (12) are symmetrical about the two mold cavities (11). A rectangular groove (13) is horizontally opened in the middle of the fixed mold (6), and the rectangular groove (13) connects the two circular holes (12). Circular spring grooves (14) are opened in the middle of the rectangular groove (13) at the upper and lower parts. A through hole (15) for connecting the rectangular groove (13) with the upper and lower mold cavities (11) is opened in the middle of the upper and lower spring grooves (14). A sliding rod (16) is slidably installed in the middle of the two through holes (15). The two sliding rods (16) extend into the rectangular groove (13) from the upper and lower mold cavities (11) respectively. One end of the two sliding rods (16) in the mold cavity (11) is fixedly installed with a push rod. The two mold cavities (11) are provided with grooves (20) at the bottom for cooperating with the push plate (17), and one end of the two slide bars (16) in the rectangular groove (13) is fixedly installed with a limit plate (18), and the two slide bars (16) are evenly wound with springs (19), one end of the two springs (19) is respectively fixed to the bottom of the upper and lower spring grooves (14), and the other end is respectively fixedly installed on the two limit plates (18), a cross plate (21) is horizontally arranged in the middle of the rectangular groove (13), and the cross plate (21) is located between the two limit plates (18), and round rods (22) are fixedly installed on the left and right sides of the upper and lower surfaces of the cross plate (21), and the four round rods (22) can slide up and down in the two round holes (12).

2. A plastic mold for producing PET plastic cups according to claim 1, Features: One end of the four round rods (22) away from the rectangular groove (13) extends out of the upper and lower surfaces of the fixed mold (6) respectively when not in operation.

3. A plastic mold for producing PET plastic cups according to claim 2, Features: A ball groove (23) is provided around the middle part of each of the four round rods (22), and balls (24) are arranged in the ball groove (23).

4. A plastic mold for producing a PET plastic cup according to claim 3, Features: A preheating device (25) is installed around the two mold cavities (11); a disc (26) is fixedly installed on one end of the four round rods (22) extending out of the fixed mold (6); circular grooves (27) for cooperating with the four discs (26) are opened on the upper and lower surfaces of the fixed mold (6); switches (28) are installed at the bottom of the circular grooves (27) on the right sides of the upper and lower surfaces; and the switch (28) is electrically connected to the preheating device (25).

5. A plastic mold for producing PET plastic cups according to claim 1, Features: The frame (1) also includes a supporting device, which includes a supporting plate (29) spanning the conveyor belt (2) and horizontally arranged between the conveyor belt (2) and the fixed mold (6), the supporting plate (29) is made of steel and has a thickness of 20 mm or more, and supporting cylinders (30) are arranged on the left and right sides of the lower plate surface of the supporting plate (29), and the output ends of the two supporting cylinders (30) are arranged vertically upward, and the output ends of the two supporting cylinders (30) are fixed to the lower plate surface of the supporting plate (29), and the two supporting cylinders (30) are installed on the frame (1) on the side opposite to the conveying direction of the conveyor belt (2); A hard rubber block (31) is fixedly mounted on the upper surface of the support plate (29); A code disc (32) is fixedly mounted on the long rotating shaft (8), and the code disc (32) is located between the fixed mold (6) and the frame (1). The code disc (32) is a metal disc, and two notches (33) are provided on the code disc (32). The two notches (33) are evenly distributed on the code disc (32) at an angle of 180°. A mounting plate (34) is horizontally fixedly mounted on one side of the long rotating shaft (8) of the frame (1), and the mounting plate (34) is aligned with the long rotating shaft (8). A proximity switch (35) is fixedly mounted on the mounting plate (34), and the proximity switch (35) is aligned with the code disc (32). The proximity switch (35) is electrically connected to the right-angle motor (10).

6. A plastic mold for producing PET plastic cups according to claim 5, Features: Four limiting holes (36) are provided at the position where the long rotating shaft (8) and the frame (1) are installed. The four limiting holes (36) are evenly arranged on the long rotating shaft (8), and the four limiting holes (36) are all on the same vertical plane. Steel balls (37) are arranged inside the four limiting holes (36), and springs (38) are arranged between the four steel balls (37) and the bottoms of the limiting holes (36). The frame (1) is provided with four spherical grooves (39) for cooperating with the limiting holes (36).

Images