Bottle caps and molding dies used for encapsulating liquid beverages in plastic bottles.

Abstract

This invention discloses a bottle cap and molding die for packaging liquid beverages in plastic bottles, belonging to the field of anti-theft plastic bottle cap design and manufacturing technology. It provides a bottle cap and molding die for packaging liquid beverages in plastic bottles with a relatively short manufacturing process and significantly reduced production costs. The bottle cap includes a plastic bottle body and a sealing cap. Corresponding tightening threads are provided on the bottle mouth wall of the plastic bottle body and the inner side wall of the sealing cap. From the outside in, at least one anti-theft ring and one anti-theft ring are sequentially provided at the open end of the sealing cap. A fixing protrusion is provided on the bottle mouth side wall below the tightening threads. The anti-theft ring, folded into the inner cavity of the sealing cap with the cooperation of the anti-theft ring, is a one-time injection molded pre-folded ring at the open end of the sealing cap. The anti-theft ring, after the liquid beverage packaging is completed, is fixed to the bottle mouth of the plastic bottle body by the anti-theft ring and the fixing protrusion.

Description

Technical Field

[0001] This invention relates to a bottle cap, and more particularly to a bottle cap for encapsulating liquid beverages in plastic bottles, belonging to the field of anti-theft plastic bottle cap design and manufacturing technology. This invention also relates to a molding die for manufacturing the aforementioned bottle cap for encapsulating liquid beverages in plastic bottles. Background Technology

[0002] Most plastic bottle caps currently used in beverage packaging have an tamper-evident ring on the open end to indicate whether the seal has been activated. When the cap is unscrewed, the tamper-evident ring is blocked by a retaining ring on the bottle neck, and the bridge between the tamper-evident ring and the cap begins to stretch until it cracks. The problem is that in the initial stage of opening the cap, the tamper-evident ring also rotates and rises simultaneously with the cap, and the bridge is not affected. However, at this point, the seal of the cap has already been broken, thus serving its purpose of indicating whether the seal has been activated.

[0003] To ensure a tight seal between the plastic bottle cap and the bottle opening, the following structural methods are currently commonly used. 1. A sealing gasket that fits axially against the bottle neck end. 2. A sealing ring that fits radially against the outer side of the bottle opening. 3. A hollow inner plug that fits radially against the inside of the bottle opening.

[0004] Because plastic materials lack sufficient resilience, all three sealing methods mentioned above require high manufacturing precision and sealing strength. Even so, the sealing effect is not as ideal as that of rubber stoppers used in pharmaceuticals. Even a slight deformation or angular misalignment of the cap and bottle opening under unintentional external force will compromise the sealing performance.

[0005] The tamper-evident ring and connecting bridge are formed by circumferential cutting of the bottom of the injection-molded bottle cap during subsequent processing. Simultaneously, the anti-reverse ring connects with the tamper-evident ring during injection molding, forming an outward V-shape. To ensure usability during filling, traditional folding caps require auxiliary equipment to cut the ring and fold the edge after injection molding before proceeding to the subsequent filling and sealing stages. The traditional reverse folding cap's reverse fold edge is molded downwards for easy demolding, and the sealing ring is a positive cone to facilitate product ejection. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide a bottle cap for packaging liquid beverages in plastic bottles with a relatively short manufacturing process and significantly reduced production cost. This application also provides a molding die for manufacturing the bottle cap for packaging liquid beverages in plastic bottles.

[0007] The technical solution adopted to solve the above-mentioned technical problems is as follows: a bottle cap for packaging liquid beverages in plastic bottles, comprising a plastic bottle and a bottle cap, wherein corresponding tightening threads are respectively provided on the bottle mouth wall of the plastic bottle and the inner side wall of the bottle cap, and at least one anti-theft ring and one anti-theft ring are respectively provided at the end of the open side of the bottle cap from the outside to the inside, and a fixing protrusion is provided on the bottle mouth side wall below the tightening threads. The anti-theft fixing ring, which is folded into the inner cavity of the bottle cap in cooperation with the anti-theft ring, is a one-time injection molded pre-folded at the end of the open side of the bottle cap; the anti-theft ring after the liquid beverage packaging is completed is limited to the bottle mouth of the plastic bottle by the anti-theft fixing ring in cooperation with the fixing protrusion.

[0008] Furthermore, the anti-theft ring and the reverse-folding fixing ring are flexibly connected by a ∠-shaped flexible ultra-thin pre-bent hook.

[0009] The preferred embodiment of the above scheme is that the tamper-evident ring and the open end of the bottle cap are intermittently connected by a circumferentially arranged tensile rib.

[0010] Furthermore, the tensile rib is formed in a single circumferential cut during the injection molding process of the bottle cap, between the tamper-evident ring and the open end of the bottle cap.

[0011] The preferred embodiment of the above scheme is that, along the circumferential direction, an axially extending anti-leakage protrusion is also provided on the inner side of the sealed end of the bottle cap.

[0012] Furthermore, a circumferentially extending inverted cone is provided at the root of the inner side of the leak-proof protrusion ring.

[0013] The molding die for manufacturing the bottle cap for packaging liquid beverages in plastic bottles includes an inner wall structure component, an outer wall structure component, and an ejector assembly. The injection cavity for packaging the bottle cap is constructed by the inner wall structure component and the outer wall structure component in cooperation with the ejector assembly. At the end of the inner wall of the injection cavity formed by the inner wall structure component, a reverse-folding fixing annular cavity communicating with the injection cavity is provided. The reverse-folding fixing annular cavity is formed in one injection molding process with the bottle cap during the injection molding process. The packaged bottle cap, after injection molding, is removed from the molding die by the ejector assembly in cooperation with the inner wall structure component.

[0014] A preferred embodiment of the above scheme is that the molding die further includes a ring-cut half block, which is arranged between the unloading ejector assembly and the outer wall structure assembly of the mold cavity in cooperation with the inner wall structure assembly of the mold cavity. The ring-cut groove between the anti-theft ring and the open end of the bottle cap is formed by the ring-cut half block in one go during the injection molding process.

[0015] Furthermore, the mold cavity inner wall structure components include an inner core, a sealing support core, a threaded core, and a reverse-folding core. The sealing support core is fitted onto the inner core, the threaded core is fitted onto the sealing support core, and the reverse-folding core is fitted onto the threaded core below the ring-cut half block. The anti-leakage annular cavity is constructed by the inner core and the threaded core in cooperation with the sealing support core. On the side wall of the inner core located at one end of the injection cavity, there are mutually adaptive ejection inverted cone protrusions extending circumferentially. The reverse-folding fixing ring cavity is constructed by the threaded core in cooperation with the reverse-folding core.

[0016] The preferred embodiment of the above scheme is that the ejector mold assembly consists of a set of ejector rings, the outer wall structure assembly of the mold cavity consists of a set of cavity modules, the cavity modules are provided with injection cavity recesses that form the outer wall of the encapsulated bottle cap, the inner side wall of the ring-cut half block is provided with ring-cut groove protrusions along the circumferential direction, the ejector ring sleeved on the reverse folding core is in contact with the lower end face of the ring-cut half block, and the lower end face of the cavity module is in contact with the upper end face of the ring-cut half block.

[0017] The beneficial effects of this invention are as follows: Based on existing plastic bottle bodies and bottle caps, this application incorporates the structural feature of providing corresponding tightening threads on the bottle mouth wall of the plastic bottle body and the inner side wall of the bottle cap. Then, from the outside in, at least one folding fixing ring and one anti-theft ring are sequentially provided at the end of the open side of the bottle cap. A fixing protrusion is further provided on the bottle mouth side wall below the tightening threads. The folding fixing ring, folded into the inner cavity of the bottle cap with the cooperation of the anti-theft ring, is pre-folded at the end of the open side of the bottle cap through a one-time injection molding process. Thus, after the liquid beverage packaging is completed, the anti-theft ring is fixed to the bottle mouth of the plastic bottle body by the folding fixing ring in cooperation with the fixing protrusion. This solves the problem in the prior art where at least one folding is required after the bottle cap is injection molded to form the folding fixing ring folded into the inner cavity of the bottle cap, thereby shortening the manufacturing process and significantly reducing production costs. Attached Figure Description

[0018] Figure 1 This is a three-dimensional structural diagram of the bottle cap used for packaging liquid beverages in plastic bottles according to the present invention; Figure 2 This is a front view of the bottle cap used for packaging liquid beverages in plastic bottles according to the present invention; Figure 3 for Figure 2 AA section view; Figure 4 This is a schematic cross-sectional view of the main section of the mold for manufacturing a bottle cap for packaging liquid beverages in plastic bottles according to the present invention. Figures 5-9The following is a schematic diagram of the process of manufacturing a bottle cap for packaging liquid beverages in plastic bottles according to the present invention: opening the mold cavity, opening the mold half block, first-stage ejection to accommodate the inner plug, second-stage ejection to disengage the thread and reverse fold, and thread and push ring ejection and reset. Figure 10 This invention provides a diagram of the inner core resetting process for a molding die used to manufacture bottle caps for packaging liquid beverages in plastic bottles. The process is as follows: due to the inverted design of the inner plug, the product remains on the inner core. The inner core is reset, and the product is pressed and shaped using a threaded core, while the product is simultaneously ejected.

[0019] The markings in the diagram are as follows: 1. Bottle cap; 2. Tightening thread; 3. Reverse folding fixing ring; 4. Anti-theft ring; 5. ∠-shaped flexible ultra-thin pre-bending hook; 6. Tension rib; 7. Leak-proof protruding ring; 8. Mold cavity outer wall structure assembly; 9. Unloading and ejection assembly; 10. Injection cavity; 11. Reverse folding fixing annular cavity; 12. Ring-cut half block; 13. Ring-cut groove; 14. Inner core; 15. Sealing support core; 16. Threaded core; 17. Reverse folding core; 18. Leak-proof protruding annular cavity; 19. Ejection inverted cone protrusion; 20. Ejection inverted cone. Detailed Implementation

[0020] like Figure 1 , Figure 2 , Figure 3 as well as Figure 4The illustration shows a bottle cap for packaging liquid beverages in plastic bottles, which has a relatively short manufacturing process and significantly reduced production costs, as provided by the present invention, and a molding die for manufacturing the bottle cap for packaging liquid beverages in plastic bottles. The bottle cap includes a plastic bottle body and a bottle cap 1. Corresponding tightening threads 2 are respectively provided on the bottle mouth wall of the plastic bottle body and the inner side wall of the bottle cap 1. From the outside in, at least one anti-theft ring 3 and one anti-theft ring 4 are sequentially provided at the end of the open side of the bottle cap. A fixing protrusion is provided on the bottle mouth side wall below the tightening threads. The anti-theft ring 3, folded into the inner cavity of the bottle cap with the cooperation of the anti-theft ring 4, is a one-time injection molded pre-folded ring at the end of the open side of the bottle cap. The anti-theft ring 4, after the liquid beverage packaging is completed, is fixed to the bottle mouth of the plastic bottle body by the anti-theft ring 3 and the fixing protrusion. This application is based on existing plastic bottle bodies and bottle caps. It incorporates the structural feature of appropriately fitted tightening threads on the bottle mouth wall of the plastic bottle and the inner wall of the bottle cap. Then, from the outside in, at least one fold-back fixing ring and one anti-theft ring are sequentially set at the end of the open side of the bottle cap. A fixing protrusion is then set on the bottle mouth side wall below the tightening threads. The fold-back fixing ring, folded into the inner cavity of the bottle cap with the cooperation of the anti-theft ring, is pre-folded at the end of the open side of the bottle cap through a one-time injection molding process. Thus, after the liquid beverage packaging is completed, the anti-theft ring is fixed to the bottle mouth of the plastic bottle body by the fold-back fixing ring and the fixing protrusion. This solves the problem in existing technologies where at least one fold is required after the bottle cap is injection molded to form the fold-back fixing ring folded into the inner cavity of the bottle cap, thereby shortening the manufacturing process and significantly reducing production costs.

[0021] Accordingly, to facilitate subsequent filling and sealing, while minimizing the process flow and reducing production costs, the tamper-evident ring 4 and the open end of the bottle cap 1 are intermittently connected by a circumferentially arranged tensile rib 6. Preferably, the tensile rib 6 is formed in a single circumferential cut during the injection molding process between the tamper-evident ring 4 and the open end of the bottle cap 1.

[0022] Meanwhile, to facilitate subsequent use by consumers and demolding during the injection molding process, the anti-theft ring 4 and the reverse-folding fixing ring 3 are flexibly connected by a ∠-shaped flexible ultra-thin pre-bending hook 5; and along the circumferential direction, an axially extending anti-leakage protrusion ring 7 is also provided on the inner side of the sealed end of the bottle cap. Preferably, an axially extending ejection inverted cone 20 is also provided at the root of the inner side of the anti-leakage protrusion ring 7, and the pre-bending hook has a smooth transition structure both inside and out.

[0023] Furthermore, in order to minimize the injection molding process in manufacturing, the molding die for manufacturing the bottle cap for packaging liquid beverages in plastic bottles provided in this application includes an inner wall structure component, an outer wall structure component 8, and an ejector mold component 9. The injection cavity 10 of the bottle cap 1 is constructed by the inner wall structure component and the outer wall structure component 8 in cooperation with the ejector mold component 9. The characteristic is that: at the end of the inner wall structure component forming the inner wall of the injection cavity, a reverse-folding fixing annular cavity 11 is provided, which communicates with the injection cavity 10. The reverse-folding fixing ring 3 is formed by injection molding the bottle cap 1 with the bottle cap 1 in one step during the injection molding process of the bottle cap 1 through the reverse-folding fixing annular cavity 11. The bottle cap 1 after injection molding is removed from the molding die by the ejector mold component 9 in cooperation with the inner wall structure component.

[0024] More specifically, the molding die also includes a ring-cut half-block 12. The ring-cut half-block 12, in cooperation with the inner wall structure assembly of the mold cavity, is arranged between the ejector assembly 9 and the outer wall structure assembly 8 of the mold cavity. The ring-cut groove 13 between the anti-theft ring 4 and the open end of the bottle cap is formed in one step during injection molding by the ring-cut half-block 12. Preferably, the inner wall structure assembly of the mold cavity includes an inner core 14, a sealing support core 15, a threaded core 16, and a reverse-folding core 17. The sealing support core 15 is sleeved on the inner core 14, the threaded core 16 is sleeved on the sealing support core 15, and the reverse-folding core 17 is sleeved on the threaded core 16 below the ring-cut half-block 12. The leak-proof annular cavity 18 is constructed by the inner core 14 and the threaded core 16 in cooperation with the sealing support core 15. A circumferentially extending groove is provided on the side wall of the inner core 14 at one end of the injection cavity 10. The ejector cone protrusions 19 are mutually adapted; the reverse folding fixing ring cavity 11 is constructed by the threaded core 16 in cooperation with the reverse folding core 17; the ejector mold assembly 9 is composed of a set of push rings; the mold cavity outer wall structure assembly 8 is composed of a set of cavity modules; the cavity module is provided with injection cavity recesses that form the outer wall of the encapsulated bottle cap; the ring-cut half block 12 is provided with ring-cut groove protrusions on the inner side wall along the circumference; the push ring sleeved on the reverse folding core 17 is in contact with the lower end face of the ring-cut half block 12; the lower end face of the cavity module is in contact with the upper end face of the ring-cut half block 12.

[0025] The process of ejecting the bottle cap after injection molding in this application is as follows: Figure 5-10 As shown.

[0026] In summary, the technical solution provided in this application also has the following advantages: 1. Compared to the traditional fold-over cap design, the new solution eliminates the ring cutting and edge folding processes, allowing direct entry into the subsequent filling and capping stages after injection molding. This significantly reduces equipment and labor costs.

[0027] 2. New type of folding cover, with the reverse folding edge pre-folded upwards, intermittent reverse folding facilitates demolding, and the top of the sealing ring has an inverted cone section for easy secondary reverse folding and shaping.

Claims

1. A bottle cap for packaging liquid beverages in plastic bottles, comprising a plastic bottle body and a bottle cap (1), wherein corresponding tightening threads (2) are respectively provided on the bottle mouth wall of the plastic bottle body and the inner side wall of the bottle cap (1), characterized in that: From the outside to the inside, at least one anti-theft ring (4) and one anti-theft ring (3) are respectively set at the end of the open side of the bottle cap. A fixing protrusion is set on the side wall of the bottle mouth below the tightening thread (2). The anti-theft ring (3) folds into the inner cavity of the bottle cap with the cooperation of the anti-theft ring (4). It is a one-time injection molded pre-folded anti-theft ring at the end of the open side of the bottle cap. The anti-theft ring (4) of the liquid beverage packaging is limited to the bottle mouth of the plastic bottle body by the anti-theft ring (3) with the cooperation of the fixing protrusion.

2. The bottle cap for packaging liquid beverages in plastic bottles according to claim 1, characterized in that: The anti-theft ring (4) and the reverse folding fixing ring (3) are flexibly connected by a ∠-shaped flexible ultra-thin pre-bent hook (5).

3. The bottle cap for packaging liquid beverages in plastic bottles according to claim 1 or 2, characterized in that: The anti-theft ring (4) is intermittently connected to the open end of the bottle cap (1) by a circumferentially intermittently arranged tie rod (6).

4. The bottle cap for packaging liquid beverages in plastic bottles according to claim 3, characterized in that: The tension rib (6) is formed by a one-time ring cut between the anti-theft ring (4) and the open end of the sealing bottle cap (1) during the injection molding process.

5. The bottle cap for packaging liquid beverages in plastic bottles according to claim 4, characterized in that: Along the circumferential direction, an axially extending anti-leakage protrusion (7) is also provided on the inner side of the sealed end of the bottle cap.

6. The bottle cap for packaging liquid beverages in plastic bottles according to claim 5, characterized in that: A circumferentially extending inverted cone (20) is also provided at the root of the leak-proof protruding ring (7).

7. A molding die for manufacturing a bottle cap for packaging liquid beverages in a plastic bottle as described in claim 6, comprising an inner wall structure assembly, an outer wall structure assembly (8), and an ejector assembly (9), wherein the injection cavity (10) for packaging the bottle cap (1) is constructed by the inner wall structure assembly and the outer wall structure assembly (8) in cooperation with the ejector assembly (9), characterized in that: At the end of the cavity wall of the injection molding cavity, which is formed by the cavity wall construction components, there is a reverse-folding fixed annular cavity (11) that communicates with the injection molding cavity (10). The reverse-folding fixed ring (3) is formed by injection molding with the bottle cap (1) in one step during the injection molding process of the bottle cap (1) through the reverse-folding fixed annular cavity (11). The bottle cap (1) after injection molding is removed from the mold by the ejector push mold assembly (9) in cooperation with the cavity wall construction components.

8. The molding die according to claim 7, characterized in that: The molding die also includes a ring-cut half block (12), which is arranged between the unloading push mold assembly (9) and the outer wall structure assembly (8) in cooperation with the inner wall structure assembly of the mold cavity. The ring-cut groove (13) between the anti-theft ring (4) and the open end of the bottle cap is formed by the ring-cut half block (12) in one go during the injection molding process.

9. The molding die according to claim 8, characterized in that: The cavity inner wall structure components include an inner core (14), a sealing support core (15), a threaded core (16), and a reverse core (17). The sealing support core (15) is fitted onto the inner core (14), the threaded core (16) is fitted onto the sealing support core (15), and the reverse core (17) is fitted onto the threaded core (16) below the ring-cut half block (12). The anti-leakage annular cavity (18) is constructed by the inner core (14) and the threaded core (16) in cooperation with the sealing support core (15). A circumferentially extending ejector cone protrusion (19) is provided on the side wall of the inner core (14) located at one end of the injection cavity (10). The reverse fixed ring cavity (11) is constructed by the threaded core (16) in cooperation with the reverse core (17).

10. The molding die according to claim 9, characterized in that: The ejector assembly (9) consists of a set of ejector rings, and the outer wall structure assembly (8) consists of a set of cavity modules. The cavity modules are provided with injection cavity recesses that form the outer wall of the bottle cap. The inner wall of the ring-cut half block (12) is provided with ring-cut groove protrusions along the circumferential direction. The ejector ring sleeved on the reverse core (17) is in contact with the lower end face of the ring-cut half block (12), and the lower end face of the cavity module is in contact with the upper end face of the ring-cut half block (12).

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