A built-in core-pulling mechanism, blow molding mold and flash removal method

Abstract

The application discloses a built-in core-pulling mechanism, a blow molding mold and a flash removing method, and belongs to the technical field of blow molding. The built-in core-pulling mechanism comprises a moving cavity formed in a central region between two mold cavities, a first slider and a second slider with arc-shaped structures on inner sides, and a connecting part connected between the two sliders; the two sliders are constrained in the moving cavity, are moved out to close the cavity in the mold cavity when the mold is closed, and are retreated into the moving cavity without exceeding the outer contour of the mold frame when the mold is opened. The blow molding mold comprises the core-pulling mechanism and a flash removing device, the flash removing device is synchronously driven by a first actuator to cut the bottle opening flash and the handle flash in a single movement, and a second actuator drives a bottom cutting support to cut off the bottom flash and supports the container. The application can reduce the transverse space occupation of the mold, simplify the structure of the flash removing driving system, realize the synchronous removal of flash in multiple positions, and improve the production efficiency.

Description

Technical Field

[0001] The present invention relates to the field of blow molding technology, and in particular to a built-in core-pulling mechanism for a blow mold for a container with a handle, a blow mold including the built-in core-pulling mechanism, and a method for removing flash from a blow molded container. Background Technology

[0002] Extrusion blow molding is a widely used process for producing hollow plastic containers. When molding containers with concave structures (such as handles), a side core-pulling slider needs to be set in the mold to form the inverted part of the handle. During demolding, the slider must exit before the mold body to separate the handle part from the mold cavity so that the product can be easily removed.

[0003] Currently, in blow molding dies for handled containers with multiple cavities, such as "one-out-two" molds, the side core-pulling mechanism is usually located on both sides of the outside of the mold. Before mold opening, the corresponding sliders retract outwards to make room for the handle's undercut. This external design significantly increases the overall width of the mold, placing higher demands on the mold platen size of the blow molding machine and limiting the possibility of accommodating more cavities within a limited space to increase production capacity.

[0004] In addition, blow-molded containers have flash at the bottle mouth, bottle bottom, and handle inner hole after demolding, which needs to be removed in subsequent processes. Several automated flash removal solutions have been proposed in the existing technology.

[0005] For example, Chinese utility model patent CN217169718U discloses a high-efficiency fully automatic blow molding die for removing sprue edge, which includes a main mold, a secondary mold, and a sprue removal device. This device uses a pushing device to drive an upper pusher to cut off the sprue material on the upper side of the product. Then, a sprue removal cylinder drives a rack to rotate a shaft, and a sprue material pushing device removes the sprue material from the handle through a rotating impact. In this solution, the removal of the sprue edge from the handle relies on a separate sprue removal cylinder and a gear and rack transmission mechanism, which is relatively complex. Furthermore, the rotating impact method easily generates lateral torque on the product, affecting the stability of the product's posture.

[0006] For example, Chinese invention patent CN100376378C discloses a bottle neck cutting mechanism for an automatic blow molding machine. This patent specifically points out the technical problem that the bottle neck of a hollow container is prone to displacement and deformation when cutting the fringe. It proposes a solution using guide positioning rollers to clamp and position the bottle neck from the outside to form a stable support point before cutting. Although this solution solves the bottle neck deformation problem to some extent, it requires an additional complex guide positioning roller mechanism, increasing the structural complexity of the device.

[0007] In the process of realizing this invention, the inventors found that the prior art has at least the following problems: First, the side core-pulling mechanism of the blow molding mold for the handle container occupies a lot of lateral space due to its external placement, which is not conducive to the compact design of the mold and the layout of high cavity number; Second, in the existing automated flash removal scheme, the removal of the handle flash and the cutting of the bottle mouth flash often rely on independent drive sources or adopt a rotational striking method, which has the problems of complex structure and difficulty in ensuring complete synchronization of multiple actions.

[0008] The embodiments of the present invention are improvements made to solve the above problems. Summary of the Invention

[0009] The purpose of this invention is to provide a built-in core-pulling mechanism, a blow mold including the built-in core-pulling mechanism, and a method for removing flash. By implementing this invention, the lateral space occupied by the mold can be reduced, the structure of the flash removal drive system can be simplified, and the flash in multiple parts can be removed simultaneously.

[0010] To achieve the aforementioned objective, in a first aspect, embodiments of the present invention provide a built-in core-pulling mechanism for a blow molding mold of a container with a handle. The blow molding mold has a main body forming a first molding cavity and a second molding cavity. The technical solution adopted is as follows:

[0011] The built-in core-pulling mechanism includes: a moving cavity formed in the central region of the mold frame between the first molding cavity and the second molding cavity; a first slider and a second slider, respectively corresponding to the first molding cavity and the second molding cavity, each slider having an arc-shaped structure on its inner side, the arc-shaped structure being configured to fit together with the inner wall of the corresponding mold cavity to form a complete cavity when the mold is closed; and a connecting part connecting the first slider and the second slider, enabling the first slider and the second slider to move synchronously; wherein, both the first slider and the second slider are constrained within the moving cavity and are configured to reciprocate synchronously within the moving cavity in a direction toward or away from the central axis of the mold frame; in the mold-closed state, the first slider and the second slider move out of the moving cavity to the corresponding first molding cavity and the second molding cavity, respectively, to close the mold cavity and form a complete cavity; in the demolding state, the first slider and the second slider move out of the corresponding mold cavity and retract into the moving cavity, and the entire retraction stroke of the first slider and the second slider is completed within the outer contour of the mold frame defined by the main body.

[0012] By constraining both the first and second sliders within the moving cavity of the mold base's central area, and ensuring that the entire retraction stroke of the sliders is enveloped within the outer contour of the mold base defined by the main body, the problem of excessively large lateral dimensions caused by arranging the side core-pulling mechanism on both sides of the mold exterior in traditional solutions is avoided. This makes the overall mold structure more compact, enabling multi-cavity layouts to be achieved within the limited space of the blow molding machine's template, thereby increasing single-machine production capacity.

[0013] Optionally, the arc-shaped structure of the slider and the inner wall of the mold cavity together form a high-pressure gas sealing system when the mold is closed, so as to withstand the internal air pressure of 6 bar to 10 bar during the blow molding stage without leakage. This setting ensures the sealing of the cavity during the blow molding process and guarantees product quality.

[0014] Optionally, the built-in core-pulling mechanism also includes a control system configured to execute a timing program: first, a command signal is sent to the first and second sliders to retract into the moving cavity; after the sensors confirm that the first and second sliders have moved out of the mold cavity and into the moving cavity, a command is then sent to open the two half-molds of the main body laterally to both sides. This "core-pulling first, mold-opening later" timing control method ensures that the sliders are completely disengaged from the concave structure of the container before the mold opens, avoiding damage to the product during demolding.

[0015] Secondly, a blow molding die is provided for molding a container with a handle. The blow molding die includes: a main body, which is composed of two half-molds, forming a first molding cavity and a second molding cavity in a closed state; any of the built-in core-pulling mechanisms of the first aspect; and a flash removal device connected to the main body for receiving the molded container after it has been removed from the main body and removing the flash from the container; wherein the flash removal device includes: a support clamp for clamping the upper and lower parts of the molded container; a first actuator mounted on the flash removal device, the first actuator being configured to move as a whole toward the flash removal device, and the drive shaft of the first actuator being connected to a bottle neck trimming assembly; the support clamp... A support plate is mounted on the first actuator, and a handle flash-cutting component is connected to the lower end of the support plate. A second actuator is mounted on the flash-removing device and located below the first actuator. The drive shaft of the second actuator is connected to a bottom edge-cutting support component, which is configured to move at the bottom of the container when the drive shaft of the second actuator moves, so as to cut off the flash at the bottom of the container and support the bottom of the container. When the first actuator moves as a whole toward the flash-removing device, the bottle mouth edge-cutting assembly cuts off the flash at the top of the container and the bottle mouth. At the same time, the support plate drives the handle flash-cutting component to move synchronously to cut off the flash at the inner hole of the handle.

[0016] In the aforementioned blow molding die, by associating the bottle neck trimming assembly and the handle flash trimming component with the same first actuator, the single overall movement of the first actuator synchronously drives the trimming of both the bottle neck flash and the handle flash. This eliminates the need for a separate drive source for the handle flash trimming, simplifying the drive system. Simultaneously, the bottom trimming support driven by the second actuator serves both to support the container bottom and trim the bottom flash, cooperating with the support clamp to form an upper and lower clamping mechanism, ensuring the container remains stable during the flash trimming process.

[0017] Optionally, the second actuator is mounted on the same side of the deflash removal device as the first actuator. The second actuator is used to drive the bottom edge-cutting support to move at the bottom of the container, so that the bottom edge-cutting support provides a vertically upward supporting force to the bottom of the container while cutting off the deflash at the bottom of the container.

[0018] Optionally, both the first actuator and the second actuator are cylinders.

[0019] Optionally, the first actuator is connected to the support plate through a mechanical linkage mechanism, so that the overall movement of the first actuator is synchronized with the movement of the handle flash punching part. The linkage mechanism is used to achieve linkage, so that the bottle mouth cutting and handle flash punching are physically synchronized, avoiding the problem of asynchronous action caused by timing errors in electrical control.

[0020] Optionally, the handle flash cutter is passed through the inner hole of the container's handle in a linear insertion-extraction manner to remove the flash at the handle's inner hole. Compared to the rotary impact method, the linear insertion-extraction method for removing the handle flash does not generate lateral torque, thus maintaining the container's posture stability during the flash removal process.

[0021] Optionally, the support clamp includes an upper clamping member and a lower clamping member. The upper clamping member is used to clamp the bottle neck or upper area of ​​the container, and the lower clamping member is linked with a bottom cut-edge support member driven by a second actuator to clamp the lower part of the container while supporting the bottom of the container.

[0022] Thirdly, a method for removing flash from blow-molded containers is provided. The method includes: clamping the upper and lower parts of the molded container using a support clamp; driving a first actuator to move as a whole towards the container, the drive shaft of the first actuator being connected to a bottle neck trimming assembly, a support plate being provided on the first actuator, and a handle flash cutting component being connected to the lower end of the support plate; during the movement of the first actuator, the bottle neck trimming assembly cuts off the flash at the upper end of the container and the bottle neck, while the support plate simultaneously drives the handle flash cutting component to move synchronously to cut off the flash at the inner hole of the handle; driving the drive shaft of a second actuator to move, causing a bottom trimming support component to move at the bottom of the container to cut off the flash at the bottom of the container and provide support for the bottom of the container.

[0023] In the above method, the removal of burrs on the bottle neck and handle is achieved synchronously through a single overall movement of the first actuator. This eliminates the need for multiple independent drive sources and complex control timing for burrs in different locations, simplifying the burr removal process and improving processing efficiency.

[0024] Furthermore, the above summary does not enumerate all the features required for embodiments of the present invention, and other combinations of these feature groups may also constitute embodiments of the present invention. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of the present invention or the background art, the drawings used in the embodiments of the present invention or the background art will be described below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a three-dimensional structural diagram of the built-in core-pulling mechanism and the main body of the blow molding die in an embodiment of the present invention.

[0027] Figure 2 for Figure 1 The diagram shows a cross-sectional view of the built-in core-pulling mechanism and the main body of the blow mold in the mold-closed state.

[0028] Figure 3 for Figure 2 A cross-sectional view of the first and second molding cavities in the core-pulling state.

[0029] Figure 4 This is a side view of the flash removal device in an embodiment of the present invention.

[0030] Figure 5 for Figure 1 A schematic diagram of the structure of the first and second sliders.

[0031] Figure 6 This is a flowchart illustrating the method for removing fringe in an embodiment of the present invention. Detailed Implementation

[0032] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. It should be noted that in the description of the embodiments of the present invention, the terms "center," "inner," "outer," "upper," "lower," "left," "right," "front," "rear," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the embodiments of the present invention.

[0033] In the following description, "first molding cavity" and "second molding cavity" refer to two cavities in the same mold that can simultaneously mold two containers. For ease of understanding, the example of molding a "wine jug" or similar container with a handle is used, but the scope of protection of this embodiment is not limited to this and can also be applied to other blow-molded containers with concave structures.

[0034] In one feasible implementation, see Figures 1 to 3 and Figure 5 This invention provides a built-in core-pulling mechanism for a blow molding mold of a container with a handle. The blow molding mold has a main body 10 forming a first molding cavity 101 and a second molding cavity 102. The main body 10 is composed of two half molds, which, in the closed state, fit together to form the aforementioned first molding cavity 101 and second molding cavity 102.

[0035] The built-in core-pulling mechanism includes a moving cavity 3, a first slider 1a, a second slider 1b, and a connecting part 1c. The moving cavity 3 is formed in the central region of the mold frame between the first molding cavity 101 and the second molding cavity 102. That is, the moving cavity 3 is a cavity opened at the center of the main body, which provides a space for accommodating the movement of the slider and a guiding channel.

[0036] The first slider 1a and the second slider 1b correspond to the first molding cavity 101 and the second molding cavity 102, respectively. The inner surface of each slider (i.e., the side facing the corresponding cavity) has an arc-shaped structure. This arc-shaped structure is configured to fit together with the inner wall of the corresponding cavity to form a complete cavity when the mold is closed. It should be noted that "complete cavity" here refers to all molding surfaces, including the container body outline and the handle molding outline surface 103. The handle molding outline surface 103 is part of the cavity inner wall and is formed by a specific area of ​​the cavity inner wall. The arc-shaped structure on the inner surface of the slider is a component of the overall cavity outline, rather than corresponding solely to the handle molding outline surface.

[0037] See Figure 5 The connecting part 1c connects the first slider 1a and the second slider 1b, enabling the first slider 1a and the second slider 1b to move synchronously. Specifically, the connecting part 1c can be a connecting rod or a connecting plate, with its two ends fixedly connected to the sides of the first slider 1a and the second slider 1b opposite to the mold cavity, respectively. Thus, when the connecting part 1c moves along the central axis of the mold frame under the action of a driving mechanism (such as a hydraulic cylinder or a pneumatic cylinder), it can simultaneously drive the two sliders to extend or retract synchronously, thereby achieving synchronous closing or opening of the two mold cavities.

[0038] The first slider 1a and the second slider 1b are both constrained within the moving cavity 3 and are configured to reciprocate synchronously within the moving cavity 3 in a direction toward or away from the central axis of the mold frame. In the mold closing state, the first slider 1a and the second slider 1b are moved out of the moving cavity 3 to the corresponding first molding cavity 101 and the second molding cavity 102, respectively, to close the mold cavity and form a complete cavity. In the demolding state, the first slider 1a and the second slider 1b are moved out of the corresponding mold cavity and retracted into the moving cavity 3.

[0039] Most importantly, the entire retraction stroke of the first slider 1a and the second slider 1b is completed within the outer contour of the mold frame defined by the main body 10. That is, the slider retracts towards the center of the mold during core pulling, rather than moving to the sides of the mold, thus not increasing the lateral dimensions of the mold.

[0040] In this embodiment, by constraining both sliders within the moving cavity of the mold base's central region and retracting the sliders inwards rather than pulling them outwards, the drawback of excessively large lateral dimensions of the mold caused by traditional external side-pulling mechanisms is avoided. This design makes the overall mold structure more compact, enabling a multi-cavity layout within the limited space of the blow molding machine's mold platen, thereby increasing single-machine production capacity. Simultaneously, the connecting part allows the two sliders to move synchronously, simplifying the complexity of the drive system.

[0041] Furthermore, the arc-shaped structure of the slider and the inner wall of the mold cavity together form a high-pressure gas sealing system in the mold-closed state to withstand the internal gas pressure of 6 to 10 bar (approximately 0.6 MPa to approximately 1.0 MPa) during the blow molding stage without leakage. Specifically, in the mold-closed state, the slider is subjected to a locking force from the drive mechanism (such as a hydraulic cylinder), causing its arc-shaped structure to fit tightly against the corresponding area of ​​the inner wall of the mold cavity, forming a reliable sealing surface. This prevents high-pressure gas from escaping from the joint between the slider and the inner wall of the mold cavity during the blow molding process, thereby ensuring the product molding quality.

[0042] In a preferred embodiment, the built-in core-pulling mechanism further includes a control system. The control system is configured to execute a timing sequence: first, it sends a command signal to the first slider 1a and the second slider 1b to retract into the moving cavity 3; after the sensor confirms that the first slider 1a and the second slider 1b have moved from the mold cavity into the moving cavity 3, it then sends a command to open the two half-molds of the main body 10 laterally to both sides. This "core-pulling first, mold-opening later" timing control method ensures that the sliders are completely disengaged from the concave structure of the container before the mold opens, avoiding interference between the sliders and the product handle during demolding, thereby protecting the product's appearance quality.

[0043] In one feasible implementation, see Figures 1 to 4 This invention provides a blow molding die for molding containers with handles. The blow molding die includes a main body 10, a built-in core-pulling mechanism as described in any of the above embodiments, and a deflashing device.

[0044] The main body 10 is composed of two half molds, forming a first molding cavity 101 and a second molding cavity 102 when the mold is closed. The upper end of the main body 10 is provided with an opening 104 for the air inlet of the blow molding machine to extend into. The preform is inflated by high-pressure gas from the opening and attached to the inner wall of the mold cavity for cooling and forming.

[0045] The deflash removal device is connected to the main body 10. Specifically, the deflash removal device is located at the downstream station of the main body 10 and is spatially located on the same mold as the molding cavity. After the molding cavity completes blow molding and is opened, the molded container can be taken out of the mold cavity by an automated robot and placed into the deflash removal device for deflash removal.

[0046] See Figure 4 The deflash removal device includes a support clamp 41, a first actuator 4, a support plate 42, a second actuator 5, and associated actuating components.

[0047] The support clamp 41 is used to clamp the upper and lower parts of the molded container. The support clamp 41 includes an upper clamping member and a lower clamping member. The upper clamping member is used to clamp the bottle mouth or upper area of ​​the container, and the lower clamping member is used to clamp the bottom area of ​​the container. When the container is placed into the deflashing device by the robot arm, the support clamp 41 is the first to move, stably fixing the container on the deflashing station, providing a positioning reference and support for the subsequent edge trimming operation.

[0048] The first actuator 4 is mounted on the deflash removal device and is configured to move as a whole toward the deflash removal device (i.e. toward the container). The drive shaft of the first actuator 4 is connected to a bottle neck trimming assembly 43, which is located at the front end of the first actuator 4. When the first actuator 4 moves as a whole toward the container, the bottle neck trimming assembly 43 first contacts the upper end of the container and the bottle neck area, cutting off the deflash in that area.

[0049] Optionally, the first actuator 4 is a cylinder, whose drive shaft extends or retracts under air pressure, driving the first actuator 4 as a whole to move back and forth along the guide rail.

[0050] The support plate 42 is mounted on the first actuator 4. The lower end of the support plate 42 is connected to the handle flash punching part 7. The support plate 42 moves with the first actuator 4 as a whole, thereby driving the handle flash punching part 7 to move synchronously. The position of the handle flash punching part 7 corresponds to the position of the inner hole of the container handle.

[0051] Optionally, the first actuator 4 is connected to the support plate 42 through a mechanical linkage mechanism, so that the overall movement of the first actuator 4 is synchronized with the movement of the handle flash cutting part 7. The linkage mechanism is used to achieve linkage, and the movement of the bottle mouth cutting assembly 43 and the handle flash cutting part 7 is physically synchronized without delay, avoiding the problem of affecting the flash removal quality due to asynchronous movement caused by electrical control timing errors.

[0052] The handle flash-cutting component 7 passes through the inner hole of the container's handle in a linear insertion-extraction manner to remove the flash at the handle's inner hole. In other words, the handle flash-cutting component 7 is inserted into the handle's inner hole in a straight line and exits from the other side, cutting and separating the flash at the handle's inner hole in the process. Compared to the rotary impact method in existing technologies, this linear insertion-extraction method does not generate lateral torque, which helps maintain the container's posture stability during the flash removal process and reduces the risk of product deformation due to uneven force.

[0053] The second actuator 5 is mounted on the deflash removal device and located below the first actuator 4. The second actuator 5 and the first actuator 4 are mounted on the same side of the deflash removal device. The drive shaft of the second actuator 5 is connected to a bottom edge-cutting support 8. The bottom edge-cutting support 8 is configured to move at the bottom of the container when the drive shaft of the second actuator 5 moves, so as to cut off the deflash at the bottom of the container and support the bottom of the container.

[0054] Optionally, the second actuator 5 is a cylinder, whose drive shaft extends and retracts, causing the bottom cut-edge support 8 to move in a horizontal or near-horizontal direction.

[0055] During operation, the second actuator 5 drives the bottom cutting edge support 8 to move at the bottom of the container, so that the bottom cutting edge support 8 provides vertical upward support to the bottom of the container while cutting off the burrs at the bottom of the container. The bottom cutting edge support 8 has the dual functions of cutting and supporting: its cutting edge is used to cut off the clamped tail burrs at the bottom of the container, and its supporting surface provides support to the bottom of the container while forming an upper and lower clamping cooperation with the first actuator 4 and the support clamp 41 above, so that the entire container is stably constrained in the predetermined position during the burr removal process, avoiding tilting or deformation due to unilateral force.

[0056] Optionally, the lower clamping member of the support clamp 41 is linked with the bottom edge support member 8 driven by the second actuator 5 to clamp the lower part of the container while supporting the bottom of the container. That is, the movement of the bottom edge support member 8 and the clamping action of the lower clamping member can be designed to be synchronous or sequentially linked. When the bottom edge support member 8 moves to abut against the bottom of the container, the lower clamping member simultaneously clamps the lower part of the container, further improving the clamping stability.

[0057] In this embodiment, by associating the bottle neck trimming assembly 43 and the handle burr punching component 7 with the same first actuator 4, the single overall movement of the first actuator 4 synchronously drives the trimming of the bottle neck burr and the handle burr, eliminating the need for a separate drive source for the handle burr removal and simplifying the structure of the drive system. At the same time, through the cooperation of the support clamp 41 and the bottom trimming support component 8, the container is clamped and fixed from top to bottom during the burr removal process, keeping the container stable when subjected to trimming force, which helps to ensure trimming quality and product yield.

[0058] In one feasible implementation, see Figure 4 and Figure 6 This invention provides a method for removing flash from blow-molded containers. This method can be performed using the blow molding die or flash removal device described in any of the foregoing embodiments. The method includes the following steps:

[0059] Step S1: Use the support clamp 41 to clamp the upper and lower parts of the molded container.

[0060] After the blow-molded container is removed from the mold cavity by the robot and placed in the deflashing station, the upper and lower clamping parts of the support clamp 41 move respectively to clamp the bottle mouth or upper and bottom areas of the container, so that the container is firmly fixed on the deflashing device, providing positioning and support for subsequent edge trimming operations.

[0061] Step S2: Drive the first actuator 4 to move as a whole toward the container. The drive shaft of the first actuator 4 is connected to the bottle mouth trimming assembly 43. A support plate 42 is provided on the first actuator 4. The lower end of the support plate 42 is connected to the handle flash punching part 7.

[0062] Step S3: During the overall movement of the first actuator 4, the bottle mouth cutting assembly 43 cuts off the burrs at the top of the container and the bottle mouth. At the same time, the support plate 42 drives the handle burr punching part 7 to move synchronously to cut off the burrs at the inner hole of the handle.

[0063] It should be noted that in step S3, the action of cutting the bottle mouth edge and the action of cutting the handle edge are completed synchronously through the same movement process of the first actuator 4 and the transmission of the mechanical linkage mechanism. There is no need to execute them in separate steps, nor is it necessary to rely on the electrical control system to coordinate the timing of multiple actuators.

[0064] Step S4: Drive the drive shaft of the second actuator 5 to move, causing the bottom edge cutting support 8 to move at the bottom of the container to cut off the burrs at the bottom of the container and provide support for the bottom of the container.

[0065] In step S4, the bottom edge-cutting support 8 provides vertical upward support to the bottom of the container while cutting off the bottom burr, forming an upper and lower clamping cooperation with the upper support clamp 41 and the first actuator 4, so that the container maintains a stable posture throughout the burr removal process.

[0066] It should be noted that the execution order of steps S2 to S4 can be adjusted according to actual process requirements. For example, step S4 (bottom trimming and support) can be performed before step S2. That is, the second actuator 5 first drives the bottom trimming support 8 to move to the support position to provide bottom support for the container, and then the first actuator 4 performs the trimming action on the bottle mouth and handle. Alternatively, steps S2 and S4 can also be performed simultaneously to shorten the processing cycle.

[0067] In this embodiment, the removal of the burrs on the bottle neck and handle is achieved synchronously through a single overall movement of the first actuator 4. This eliminates the need for multiple independent drive sources and complex control timing for burrs in different locations, simplifying the burr removal process and improving processing efficiency. Meanwhile, the bottom cutting support 8 driven by the second actuator 5 has both support and cutting functions, further simplifying the mechanism.

[0068] In a specific application scenario

[0069] This application scenario uses a specific blow molding mold for a "one-out-two" old wine jug as an example to explain in detail the working process of the built-in core-pulling mechanism.

[0070] The blow molding die is compatible with a blow molding machine with a clamping force of 20 tons, and the die size is 800mm×600mm. The main body 10 is composed of a left half mold and a right half mold, forming a first molding cavity 101 and a second molding cavity 102 that are symmetrical when the mold is closed. Each cavity is used to mold an HDPE wine jug with a capacity of 2.5 liters and a side handle.

[0071] In the mold-closed state, the connecting part 1c is pushed outward along the central axis of the mold frame under the drive of the hydraulic cylinder, causing the first slider 1a and the second slider 1b to move out of the moving cavity 3 and into the corresponding first molding cavity 101 and second molding cavity 102, respectively. The arc-shaped structure on the inner side of each slider and the inner wall of the corresponding mold cavity are joined together to form a complete cavity. Subsequently, the extruder extrudes the molten HDPE preform between the two half molds. The two half molds close and clamp the preform. The blow molding machine blows compressed air at a pressure of 8 bar into the preform through the opening 104 at the upper end of the main body 10. The preform is inflated and adheres to the inner wall of the mold cavity to cool and form. During the blow molding process, the sealing system formed between the arc-shaped structure of the slider and the inner wall of the mold cavity withstands the internal air pressure of 8 bar without leakage. The handles of the two old wine jugs after molding have clear outlines and uniform flash.

[0072] After cooling, the control system first issues a core-pulling command. The hydraulic cylinder drives the connecting part 1c to retract along the central axis of the mold frame, causing the first slider 1a and the second slider 1b to move out of the mold cavity simultaneously and retract into the moving cavity 3. After the sensor confirms that the two sliders have completely disengaged from the handle's undercut structure, the control system issues a mold-opening command, and the left and right half of the mold open laterally to both sides. Since the entire retraction stroke of the sliders is completed within the outer contour of the mold frame defined by the main body 10, the total width of the mold in the open state is 780mm, which perfectly fits the 800mm×600mm template size. The two molded old wine bottles are then removed from the mold cavity by a robotic arm and transferred to a deflashing device for further processing.

[0073] In this application scenario, the built-in core-pulling mechanism allows the total width of the mold to be controlled within the template size range, enabling "one-out-two" production on a 20-ton blow molding machine. Compared to the traditional external side core-pulling solution, which requires a larger tonnage blow molding machine, this reduces equipment investment costs.

[0074] In another specific application scenario

[0075] To further verify the necessity of the technical solution of the present invention from the reverse perspective, the following comparative examples are provided to illustrate the technical problems that arise when the key technical features of the present invention are missing.

[0076] Comparative Example 1: A blow molding mold for a two-handle wine jug using a traditional external side-pulling mechanism, with all other conditions the same as the application scenario of this invention. In this comparative example, the two handle forming sliders are respectively arranged on the left and right sides of the mold's exterior. Before mold opening, the sliders retract to the left and right sides respectively. The total width of the mold in the open state reaches 1050mm, exceeding the capacity of the 800mm×600mm template. Therefore, it cannot be used on a 20-ton blow molding machine and must be upgraded to a blow molding machine with a clamping force of 35 tons and a template size of 1000mm×800mm. The equipment investment cost increases by approximately 40%, and the energy consumption per unit product increases by approximately 15%.

[0077] Comparative Example 2: A deburring device driven by independent multi-cylinders was used. The bottle neck trimming, handle deburring, and bottom trimming were each driven by three independent cylinders and electrically synchronized via a PLC. All other conditions were the same as in the application scenario of this invention. After 1000 consecutive cycles, this comparative example showed 23 instances of timing asynchrony due to differences in the response time of the solenoid valves of different cylinders (ranging from 3ms to 8ms) and the combined effect of air pressure fluctuations. This resulted in micro-cracks in the inner hole of the handle on 7 products due to improper force, and elliptical deformation of 0.3mm to 0.5mm on the bottle neck of 3 products. The overall yield was 99.0%. However, the deburring device of this embodiment, where the bottle neck trimming and handle deburring were synchronously driven by the same first actuator via a rigid connecting rod, did not exhibit timing asynchrony under the same operating conditions, achieving an overall yield of 99.8%.

[0078] As can be seen from the above comparison, the built-in core-pulling mechanism of the present invention effectively solves the problem of excessively large mold lateral dimensions and the need for equipment upgrades caused by the external solution; the mechanical linkage deflashing solution of the present invention eliminates the product damage problem caused by timing errors in electrical synchronization control.

[0079] In yet another specific application scenario

[0080] This application scenario is described in conjunction with the instruction manual. Figures 1 to 3This demonstrates how to quickly switch product models by changing the slider when a blow molding mold needs to produce containers of different specifications, without having to replace the entire mold body.

[0081] In this application scenario, the blow molding mold originally used to produce 2.5-liter vintage wine jugs needs to be switched to produce smaller-sized vintage wine jugs with a slightly different handle inner hole shape, using a 1.8-liter mold. The contours of the first molding cavity 101 and the second molding cavity 102 of the main body 10 match the new product specifications, but the undercut depth and inner hole shape of the handle change. At this time, it is only necessary to remove the original first slider 1a and second slider 1b from the moving cavity 3 and replace them with another pair of sliders with an arc-shaped structure that matches the contour of the new handle. The connection interface between the connecting part 1c and the two new sliders is a standardized design, and there is no need to readjust the stroke parameters of the connecting part 1c after replacement. The timing program parameters in the control system (such as core pulling speed, retraction position, etc.) can be directly called through the operation interface to call the preset second set of parameter schemes.

[0082] After the replacement is completed, 3 to 5 trial runs are required to reach normal production status, with a product changeover time of less than 2 hours. Compared to the traditional solution that requires a complete mold replacement (usually taking 4 to 6 hours), the modular slider design of this invention shortens the mold changeover time and improves production line efficiency.

[0083] In this application scenario, the slider in the built-in core-pulling mechanism adopts a replaceable modular design, which allows the same mold body to be adapted to the production of containers with different handle specifications by changing the slider, thereby improving the versatility and utilization of the mold.

[0084] In a possible application scenario

[0085] In actual production, when the ambient temperature is low (such as in winter) or the blow-molded container cools excessively during the robotic transfer process due to a slightly longer waiting time, the flash on the container (especially at the bottle neck and handle inner hole) becomes harder and more brittle than normal. In this case, if the traditional rotary impact-type handle flash removal method is used, the brittle flash is prone to irregular fracture when subjected to the rotational torque impact. The fracture surface may extend into the product body, resulting in burrs or tiny notches on the edge of the handle inner hole, affecting the product's appearance and safety in use.

[0086] In the deflash removal device of the present invention, since the deflash cutting member 7 of the handle passes through the inner hole of the container handle in a linear insertion and extraction manner, its shearing force is uniformly applied to the entire cross-section of the deflash in a straight line. Even if the deflash hardens and becomes brittle due to low temperature, a regular shear separation surface can still be produced. At the same time, the support clamp 41 firmly clamps the upper and lower parts of the container, and the bottom cutting edge support member 8 supports the bottom of the container, so that the container will not shift or tilt when subjected to linear shearing force, avoiding irregular breakage caused by abnormal hardness of the deflash.

[0087] Under these abnormal conditions, after 500 consecutive cycles of operation, the products treated with the deflash removal device of this invention showed a burr rate of less than 1% at the edge of the handle inner hole and an elliptical deformation of the bottle mouth controlled within 0.2 mm. In contrast, the control group treated with the rotary impact deflash removal device showed a burr rate of 12% at the edge of the handle inner hole and an elliptical deformation of 0.5 mm to 1.0 mm at the bottle mouth.

[0088] Therefore, the present invention adopts a linear plug-in handle flash cutting method, which can maintain cutting quality and product yield even under conditions of abnormal flash hardness.

[0089] In other specific application scenarios

[0090] Extended Application 1: One-out-of-four multi-cavity mold. When the blow molding machine mold platen size is large (e.g., 1200mm × 1000mm) and further capacity increases are required, the concept of the built-in core-pulling mechanism of this invention can be extended to a "one-out-of-four" mold layout. In this layout, the main body forms four molding cavities arranged in a 2×2 matrix. A movable cavity is set between the two cavities in each row, for a total of two movable cavities. Each movable cavity contains a pair of sliders that are synchronously linked by a connecting part. All four sliders retract towards the center of the mold frame. Compared to the traditional four-cavity external design, the total mold width is reduced by approximately 25%, allowing users who would otherwise need to upgrade their equipment to achieve four-cavity capacity on their existing machines.

[0091] Extended Application 2: Application of the flash removal method in handle-less containers. The flash removal method of this invention is not only applicable to containers with handles, but also to removing flash from ordinary blow-molded containers (such as handle-less round or square bottles). When processing handle-less containers, simply adjust or remove the handle flash cutting component 7. When the first actuator 4 moves as a whole, only the bottle mouth cutting component 43 cuts off the flash at the top of the container and the bottle mouth. The second actuator 5 still drives the bottom cutting support component 8 to cut off the bottom flash and support the container. The support clamp 41 holds the upper and lower parts of the container to maintain stability. This adjustment only needs to be completed through parameter settings on the operating interface when changing product models, without requiring major modifications to the hardware structure of the flash removal device.

[0092] Those skilled in the art will understand that the specific structures and parameters of the components in the above embodiments are merely illustrative and do not constitute a limitation on the scope of protection of the present invention.

[0093] For example, the number of sliders can be increased accordingly as the number of cavities increases. When the blow mold has four or more molding cavities, a moving cavity can be set in the central area between two adjacent cavities, and two back-to-back sliders can be arranged in each moving cavity. The sliders are connected to each other to achieve synchronous linkage.

[0094] For example, the first actuator 4 and the second actuator 5 are not limited to cylinders, but can also be hydraulic cylinders, electric push rods or other types of linear actuators, as long as they can achieve the corresponding linear reciprocating motion; the selection of the drive source can be determined according to the actual working conditions (such as the required thrust, response speed, cost and other factors).

[0095] For example, the specific structure of the bottle mouth cutting component 43 can be adapted to the shape and size of the container bottle mouth, and its cutting edge can be ring-shaped, arc-shaped or straight; the shape and size of the handle flash punching part 7 can also be adjusted according to the contour of the handle inner hole.

[0096] It should be understood that the terms "one embodiment," "an embodiment," "a feasible implementation," or "some implementations" used throughout the specification mean that a specific feature, structure, or characteristic related to the embodiment is included in at least one embodiment of the present invention. Therefore, "one embodiment," "an embodiment," "a feasible implementation," or "some implementations" appearing throughout the specification do not necessarily refer to the same embodiment. Furthermore, these specific features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. Those skilled in the art should also recognize that the embodiments described in the specification are optional embodiments, and the actions and modules involved are not necessarily essential to the embodiments of the present invention.

[0097] The above description is merely a specific embodiment of the present invention, but the protection scope of the embodiments of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the embodiments of the present invention should be included within the protection scope of the embodiments of the present invention. Therefore, the protection scope of the embodiments of the present invention should be determined by the protection scope of the claims.

Claims

1. A built-in core-pulling mechanism for a blow molding die for a container with a handle, the blow molding die having a main body forming a first molding cavity and a second molding cavity, characterized in that, include: A movable cavity is formed in the central region of the mold frame between the first molding cavity and the second molding cavity; The first slider and the second slider correspond to the first molding cavity and the second molding cavity, respectively. The inner side of each slider has an arc-shaped structure, which is configured to fit together with the inner wall of the corresponding mold cavity to form a complete cavity when the mold is closed. A connecting part is provided between the first slider and the second slider, enabling the first slider and the second slider to move synchronously. The first slider and the second slider are both constrained within the moving cavity and configured to reciprocate synchronously within the moving cavity in a direction toward or away from the central axis of the mold frame. In the mold-closing state, the first slider and the second slider move out of the moving cavity into the corresponding first molding cavity and the second molding cavity, respectively, to close the mold cavity and form a complete cavity. In the demolding state, the first slider and the second slider move out of the corresponding mold cavity and retract into the moving cavity, and the entire retraction stroke of the first slider and the second slider is completed within the outer contour of the mold frame defined by the main body.

2. The built-in core-pulling mechanism according to claim 1, characterized in that, The arc-shaped structure of the slider and the inner wall of the mold cavity together form a high-pressure gas sealing system in the mold-closed state, so as to withstand the internal air pressure of 6 bar to 10 bar during the blow molding stage without leakage.

3. The built-in core-pulling mechanism according to claim 1, characterized in that, It also includes a control system configured to execute a timing program: First, a command signal is sent to the first slider and the second slider to retract into the moving cavity. After the sensor confirms that the first slider and the second slider have moved out of the mold cavity into the moving cavity, a command is then sent to open the two half molds of the main body laterally to both sides.

4. A blow molding die for molding a container with a handle, characterized in that, include: The built-in core-pulling mechanism as described in any one of claims 1 to 3; The main body is composed of two half-molds, which form a first molding cavity and a second molding cavity when the mold is closed. A flash removal device, which is connected to the main body, is used to receive the molded container after it has been removed from the main body and remove the flash from the container; The deflash removal device includes: Support clamps are used to hold the upper and lower parts of the molded container; A first actuator is mounted on the deflash removal device. The first actuator is configured to move as a whole toward the deflash removal device. The drive shaft of the first actuator is connected to a bottle neck trimming assembly. A support plate is disposed on the first actuator, and a handle flash punch is connected to the lower end of the support plate; A second actuator is mounted on the deflash removal device and located below the first actuator. The drive shaft of the second actuator is connected to a bottom edge-cutting support member, which is configured to move at the bottom of the container when the drive shaft of the second actuator moves, so as to remove the deflash at the bottom of the container and support the bottom of the container. When the first actuator moves toward the deburring device, the bottle mouth cutting assembly cuts off the burrs at the top of the container and the bottle mouth. At the same time, the support plate drives the handle burr punching part to move synchronously to cut off the burrs at the inner hole of the handle.

5. The blow molding die according to claim 4, characterized in that, The second actuator is mounted on the same side as the first actuator on the deflash removal device. The second actuator is used to drive the bottom edge cutting support to move at the bottom of the container, so that the bottom edge cutting support provides a vertical upward support force to the bottom of the container while cutting off the deflash at the bottom of the container.

6. The blow molding die according to claim 4, characterized in that, Both the first actuator and the second actuator are cylinders.

7. The blow molding die according to claim 4, characterized in that, The first actuator is connected to the support plate via a mechanical linkage mechanism, so that the overall movement of the first actuator is synchronized with the movement of the handle flash punch.

8. The blow molding die according to claim 4, characterized in that, The handle flash cutter passes through the inner hole of the container handle in a linear insertion and removal manner to remove the flash at the inner hole of the handle.

9. The blow molding die according to claim 4, characterized in that, The support clamp includes an upper clamping member and a lower clamping member. The upper clamping member is used to clamp the bottle mouth or upper area of ​​the container. The lower clamping member is linked with the bottom cut-edge support member driven by the second actuator to clamp the lower part of the container while supporting the bottom of the container.

10. A method for removing flash from blow-molded containers, characterized in that, include: The upper and lower parts of the molded container are held in place by a support clamp; The first actuator is driven to move as a whole toward the container. The drive shaft of the first actuator is connected to a bottle mouth trimming assembly. A support plate is provided on the first actuator, and a handle flash punching part is connected to the lower end of the support plate. During the overall movement of the first actuator, the bottle mouth cutting component cuts off the burrs at the top of the container and the bottle mouth, while the support plate drives the handle burr punching component to move synchronously to cut off the burrs at the inner hole of the handle. The drive shaft that drives the second actuator moves, causing the bottom edge-cutting support to move at the bottom of the container, thereby cutting off the burrs at the bottom of the container and providing support for the bottom of the container.

Images