A post-mold trim system and method for a component product

Abstract

This invention belongs to the field of injection molding technology, specifically a post-molding shaping system and method for injection molded products. The system includes a platform, four rectangularly distributed flipping pressure claw mechanisms, and a scissor-type cutting mechanism. The cutting mechanism's blades are equipped with a first detection unit to detect the force change at the moment of sprue breakage, and the flipping pressure blocks are equipped with a second detection unit to detect blade contact vibration and cutting vibration. The control unit receives the dual detection signals and determines whether the cutting is complete. This invention achieves real-time self-feedback of the cutting result through dual criteria of pressure mutation and vibration characteristics, eliminating the need for visual inspection. It features low hardware cost, strong anti-interference capabilities, and can accurately identify incompletely cut sprues and trigger recutting commands, effectively preventing defective products from flowing into the next process. It solves the technical problem of existing cutting methods lacking self-feedback functionality, which leads to rework and delayed delivery efficiency, significantly improving the cutting yield and production efficiency.

Description

Technical Field

[0001] This invention relates to the field of injection molding technology, and in particular to a post-molding shaping system and method for injection molded products. Background Technology

[0002] In the injection molding process, the removal of the sprue (i.e., the gate filler) is one of the key steps determining the final product's appearance quality and subsequent assembly accuracy. For relatively simple flat or symmetrical injection molded parts, the sprue can usually be located on the inner wall, bottom surface, or parting surface of the product, facilitating post-processing with conventional cutting tools. However, as industrial products become more functionally integrated and structurally complex, more and more injection molded shells or support brackets have complex internal structures such as reinforcing ribs, snap-fit ​​grooves, threaded pillars, and wiring channels, leaving insufficient space for the sprue. Therefore, the sprue must be designed on the outer wall surface of the product. These square shell products are often large in volume and weight. To ensure the filling speed and pressure holding effect of the molten plastic in the cavity, the sprue size must be increased accordingly, resulting in a significant increase in the thickness of the sprue filler section after molding.

[0003] In existing technologies, the cutting method for the outer wall sprue mainly uses pneumatic or electric gripper-type cutting devices, which achieve cutting by clamping two straight blades. However, due to the large thickness of the sprue, complete cutting and separation cannot be guaranteed every time. Current cutting methods lack a self-feedback function; if timely detection and feedback are not provided, it will lead to product rework and delay normal outbound efficiency.

[0004] Although there are other detection methods, such as visual inspection technology, the hardware procurement cost, technical debugging difficulty, and maintenance cost of this method are relatively high, making it not cost-effective. Summary of the Invention

[0005] The purpose of this invention is to provide a post-molding shaping system and method for injection molded products to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a post-molding shaping system for injection molded parts, comprising a platform for placing a shell workpiece to be trimmed of sprue marks, a clamping mechanism for pressing the shell workpiece onto the platform, and a cutting mechanism for trimming the sprue marks on the outer wall of the shell workpiece. The cutting mechanism includes two longitudinally hinged arms, a blade disposed at the front end of the hinged arms, and a drive assembly for driving the two hinged arms to open and close. The clamping mechanism comprises four clamping mechanisms, each disposed at one of the four corners of the platform. The flipping clamping mechanism includes a flipping clamping block and a flipping drive module for driving the flipping clamping block to flip to a clamping state. The system also includes: The first detection unit is disposed on the cutting mechanism and is used to detect the change in force at the moment of breakage of the sprue during the cutting process, and to determine whether the cutting is complete based on the change in force. The second detection unit is set on the flipping pressure block and is used to detect the contact vibration when the blade closes during the cutting process and the cutting vibration at the moment the sprue breaks, and to determine whether the cutting is complete based on the vibration signal. The control unit is connected to the first detection unit, the second detection unit, the drive component, and the flip drive module respectively, and is used to receive detection signals and control the operation of the drive component and the flip drive module.

[0007] The post-molding shaping system for injection molded parts of the present invention further includes a third detection unit disposed on one of its blades, which is used to detect in real time the distance between the two blades or the relative position between the blade and the workpiece being cut. If the two blades do not completely close after a cut, the third detection unit sends an abnormal spacing signal to the control unit, which then controls the drive assembly to perform a second cut based on the abnormal spacing signal.

[0008] The post-molding shaping system for injection molded parts of the present invention includes a third detection unit which is a ranging component disposed on one of the blades. The ranging component includes a heat insulation substrate and a ranging sensor disposed on the heat insulation substrate. The ranging sensor is a laser displacement sensor or an infrared ranging sensor, and its detection end is directed toward the other blade or toward the top of the sprue located between the two blades.

[0009] The post-molding shaping system for injection molded parts of the present invention includes a first detection unit that is a piezoelectric sheet embedded in the pushing member of the driving component. The pushing member is used to push the two hinged arms to separate. When the cut reaches the breakage of the sprue, the pressure on the piezoelectric sheet disappears. The control unit determines that the cut is complete based on the pressure change.

[0010] The post-molding shaping system for injection molded parts of the present invention includes a pushing member having two radially opposite inclined pushing portions at its front end. The two inclined pushing portions are arranged vertically opposite each other and their front ends are close to each other. The opposite sidewalls of the two hinge arms are provided with fitting inclined surfaces that cooperate with the inclined pushing portions. The inclined pushing portion includes an inclined platform and a heat insulation pad embedded in the inclined platform. The piezoelectric sheet is embedded in the heat insulation pad and is parallel to the fitting inclined surface.

[0011] The post-molding shaping system for injection molded parts of the present invention includes a blade that is bent and tilted at one end toward the hinge shaft, such that the working part at the front end of the blade is tilted and offset relative to the axis of the hinge arm; a cavity is provided on one side wall of the blade facing the bending direction, and when the two blades are closed, the two cavities together form a through cutting and discharge channel; the ranging component is located on the discharge side of the cavity.

[0012] The post-molding shaping system for injection molded parts of the present invention wherein the wall thickness of the cavity gradually decreases from both sides toward the blade closure line, so that the inner wall of the cavity forms a smooth arc-shaped transition surface.

[0013] The post-molding shaping system for injection molded parts of the present invention includes an electric heating element on at least one of the two blades. The electric heating element is arranged along the length direction of the blade and is used to heat the blade before and during cutting.

[0014] The post-molding shaping system for injection molded parts according to the present invention includes a flipping pressure claw mechanism that further comprises a base, a support, and a cylindrical structure, wherein the flipping pressure block is longitudinally hinged to the base via a flipping pivot. The flipping drive module includes a vertical linear drive assembly and a transmission connecting rod assembly. The transmission connecting rod assembly is located at the upper end of the linear drive assembly and is encapsulated by the cylindrical structure. The upper end of the transmission connecting rod assembly is hinged to the lower end of the flipping pressure block. When the linear drive assembly drives the transmission connecting rod assembly to rise, it pushes the flipping pressure block to flip around the flipping axis to a horizontal state.

[0015] Furthermore, the present invention also provides a method for post-molding shaping of injection-molded products, employing the post-molding shaping system for injection-molded products as described above, comprising the following steps: S1: Place the shell workpiece with the sprue to be cut on the platform. The control unit controls the flipping drive module of the four flipping pressure claw mechanisms to drive each flipping pressure block to flip to a horizontal state and press the shell workpiece onto the platform. S2: The control unit controls the drive component of the cutting mechanism to close the two hinged arms and drive the two blades to cut the sprue on the outer wall of the shell workpiece. S3: During the cutting process, the first detection unit detects the change in force at the moment the sprue breaks and feeds it back to the control unit; the second detection unit detects the contact vibration when the blade closes and the cutting vibration when the sprue breaks and feeds it back to the control unit. S4: If the first detection unit detects a change in force and the second detection unit detects contact vibration and cutting vibration, the control unit determines that the cutting is complete; S5: If the third detection unit detects an abnormal gap signal that the two blades are not completely closed after cutting and feeds it back to the control unit, the control unit controls the drive component to perform a second cut again. S6: After the cutting is completed, the control unit controls the flipping drive module to flip each of the flipping blocks to the initial state and remove the cut shell workpiece.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: By deploying two types of physical sensing elements at key action nodes, the process node of "whether the blade has truly and completely cut off the sprue" can be directly determined, rather than relying on external visual inspection or manual visual inspection.

[0017] Specifically, the first detection unit captures the sudden change in force caused by the chain reaction of internal stress release at the moment of sprue breakage. Its response speed can reach milliseconds and is unaffected by environmental factors such as light and dust. The second detection unit, based on the vibration time-domain characteristics, compares the contact vibration waveform generated by the blade closing impact with the impact vibration waveform generated when the sprue breaks. This effectively avoids misjudgments that may occur due to relying solely on the disappearance of pressure (for example, when the sprue is only partially cracked but not completely separated, the piezoelectric element may still output a pressure change signal due to deformation release). The two work together to virtually eliminate incomplete cutting, and the hardware cost is only one-tenth to one-fifth of that of a vision inspection system. It requires no complex optical debugging and algorithm training, is ready to use immediately, and is easy to maintain.

[0018] The introduction of the control unit enables the entire system to automatically obtain the judgment result after a single cutting action. Once an abnormality is detected, an alarm or recutting instruction is immediately triggered without manual intervention. This fundamentally solves the technical problem in the existing technology where defective products flow into the next process and rework delays the efficiency of outbound delivery due to the inability to provide real-time feedback on cutting results. Attached Figure Description

[0019] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0021] Figure 2 This is a structural diagram of the cutting mechanism of the present invention in the cutting state.

[0022] Figure 3This is an overall structural diagram of the cutting mechanism of the present invention in the view of the hinge axis.

[0023] Figure 4 This is a detailed connection structure diagram of the two hinged arms of the present invention.

[0024] Figure 5 yes Figure 4 Enlarged view of a local structure.

[0025] Figure 6 yes Figure 5 Axial sectional view.

[0026] Figure 7 This is a side view of the flipping pressure claw mechanism of the present invention.

[0027] Figure 8 for Figure 7 A longitudinal sectional view.

[0028] Figure 9 for Figure 8 Enlarged view of a local structure.

[0029] Figure 10 for Figure 8 Enlarged view of a local structure.

[0030] Figure 11 This is a control logic framework diagram of the present invention. Detailed Implementation

[0031] The terms "first," "second," "third," and "fourth," etc., used in the specification, claims, and accompanying drawings of this invention are used to distinguish different objects, not to describe a specific order. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or apparatuses.

[0032] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of the invention. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0033] "Multiple" refers to two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone. The character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0034] Furthermore, the terms indicating orientation, such as "up," "down," "left," "right," "upper end," "lower end," and "longitudinal," are all based on the posture and position of the device or equipment described in this solution during normal use.

[0035] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, a clear and complete description will be provided below in conjunction with the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the protection scope of the present invention.

[0036] like Figures 1 to 11 As shown, the post-molding shaping system for injection molded parts of the present invention mainly includes a platform 200 for placing a shell workpiece with sprue gates to be cut, a clamping mechanism for pressing the shell workpiece onto the platform 200, and a cutting mechanism 100 for cutting the sprue gates on the outer wall of the shell workpiece. Specifically, there are two cutting mechanisms 100 located at both ends of the platform, and both are brought close to and separated from the sprue gates via XY slides 400.

[0037] Specifically, the clamping mechanism consists of four rectangularly distributed flipping clamping claw mechanisms 300, which are respectively located near the four corners of the platform 200 to achieve balanced and stable clamping and positioning of the shell workpiece at the four corners.

[0038] The cutting mechanism 100 adopts a side-by-side hinged structure (not an X-shaped scissor structure), specifically including two hinged arms 1 that are hinged side-by-side, a blade 2 integrally set at the front end of the hinged arms 1, and a drive assembly 4 that drives the two hinged arms 1 to close or open. The two hinged arms 1 are hinged side-by-side through a hinge shaft 3.

[0039] The system also includes a first detection unit 500, a second detection unit 600, and a control unit. The first detection unit 500 is mounted on the cutting mechanism 100 and is used to detect the change in force at the moment the sprue breaks during the cutting process, and to determine whether the cutting is complete based on this force change. The second detection unit 600 is mounted on the flipping pressure block 302 and is used to detect the contact vibration when the blade 2 closes and the cutting vibration at the moment the sprue breaks during the cutting process, and to determine whether the cutting is complete based on the time-domain characteristics of the vibration signals. The control unit is connected to the first detection unit 500, the second detection unit 600, the drive assembly 4, and the flipping drive module 304, respectively, and is used to receive various detection signals and comprehensively control the drive assembly 4 and the flipping drive module 304 to operate according to a predetermined logical sequence.

[0040] This embodiment achieves direct determination of cutting completeness through dual physical criteria. It captures the sudden change in force caused by the chain release of internal stress at the moment of sprue breakage by the first detection unit 500, and compares and analyzes the contact vibration waveform generated by the blade closing impact with the impact vibration waveform generated when the sprue breaks by the second detection unit 600. It has a fast response speed and is not affected by environmental factors such as light and dust. The two work together to improve the accuracy of cutting completeness determination to over 99.9%. The hardware cost is only one-tenth to one-fifth of that of a vision inspection system. The control unit can automatically obtain the determination result after a single cutting action. Once an abnormality is detected, it immediately triggers a recutting command or alarm without manual intervention. This effectively solves the technical problem in the prior art where the inability to provide real-time feedback on cutting results leads to defective products flowing into the next process and rework delaying the outbound efficiency.

[0041] like Figure 2 As shown, the upper blade 2 in the cutting mechanism 100 is also equipped with a third detection unit, which is specifically a distance measuring component 6, used to detect in real time the distance between the two blades 2 or the relative positional relationship between the blade 2 and the workpiece being cut. The distance measuring component 6 is located on the bent side of the upper blade 2 and is vertically downward, with its detection end vertically facing the upper surface of the lower blade 2 or towards the top of the sprue located between the two blades 2, so as to accurately measure the gap value between the upper and lower blades 2 or the height difference between the blade 2 and the top surface of the sprue.

[0042] In actual operation, when the first detection unit 500 and the second detection unit 600 cannot make a clear judgment due to extreme working conditions (such as the thick-walled gate softening due to heat and causing ductile adhesion rather than brittle fracture), the ranging component 6 provides the most direct physical criterion. If adhesion occurs due to incomplete cutting caused by excessive gate thickness or improper temperature setting, and the upper and lower blades 2 cannot be fully closed, the ranging component 6 can immediately sense the abnormal spacing value and feed it back to the control unit. The control unit then controls the drive component 4 to perform a second recut. This third detection unit adopts a non-contact measurement method, avoiding mechanical collisions and wear, and provides reliable data support for the trigger threshold of the second recut, forming a closed-loop control link of "sensing-judgment-re-execution" to ensure that every product leaves the station in a fully cut state.

[0043] Furthermore, the ranging component 6 includes a heat-insulating base 61 and a ranging sensor 62 disposed on the heat-insulating base 61. The ranging sensor 62 is preferably a laser displacement sensor or a high-precision infrared ranging sensor. The upper blade 2, corresponding to the ranging component 6, has a mounting base 7 integrally formed at its end opposite to the lower blade 2 (i.e., the upper end of the upper blade 2). The mounting base 7 and the blade 2 are integrally forged from the same metal blank to ensure consistent connection strength and thermal conductivity. The ranging component 6 is fixedly mounted on the mounting base 7. Specifically, the heat-insulating base 61 is fixed to the upper or side surface of the mounting base 7 by fastening screws and positioning clips. A ceramic fiber layer is provided on the side of the heat insulation substrate 61 that is in contact with the mounting base 7. The ceramic fiber is specifically made of aluminum silicate cotton and is in the form of ceramic fiber paper or ceramic fiber felt. This effectively blocks the heat conduction from the high temperature at the mounting base 7 to the heat insulation substrate 61 and the internal ranging sensor 62, ensuring that the measuring accuracy of the ranging sensor 62 remains stable within ±0.02mm even when the blade 2 is heated to a high temperature of 130℃ to 230℃. The electric heating element 5 is embedded in the mounting base 7. The electric heating element 5 is preferably an electric heating tube or an electric heating rod, which is embedded in the mounting hole opened inside the mounting base 7 by compression or threading. Heat is evenly conducted from the mounting base 7 to the blade 2 that is integrated with it.

[0044] In this embodiment, the first detection unit 500 is a piezoelectric sheet 501 embedded in the pushing member 11 of the drive assembly 4. The pushing member 11 is used to squeeze between the two hinge arms 1 when the drive shaft 9 extends forward, forcing the rear ends of the two hinge arms 1 to rotate around the hinge shaft 3 and open, thereby driving the two blades 2 to close together to achieve cutting. When the cutting is carried out to the moment when the sprue is completely broken, the sprue suddenly breaks due to the release of internal stress, causing the reaction force on the piezoelectric sheet 501 to suddenly disappear. At this time, the control unit can determine that the cutting is complete based on the pressure drop signal; if there is no change in this front and back force within the predetermined stroke, it is determined that it has not been cut. This arrangement makes the piezoelectric sheet 501 extremely close to the cutting point, with a short signal transmission path and sensitive response. It can output an electrical signal change within the same control cycle (usually less than 20ms) when the break occurs, and does not require additional installation space on the blades 2 or hinge arms 1. The structure is compact and highly integrated.

[0045] Regarding the specific structure of the drive assembly 4, the drive assembly 4 includes a drive shaft 9 and a power unit body 10 that drives the drive shaft 9 to reciprocate axially. The power unit body 10 is preferably a cylinder body, which has a cylinder and a piston. The drive shaft 9 is the piston rod of the cylinder body, which reciprocates back and forth along its own axis under air pressure. The end of the drive shaft 9 is coaxially threaded with a push member 11 that pushes the two hinge arms 1 apart. When the drive shaft 9 extends forward, the push member 11 squeezes between the two hinge arms 1, forcing the two hinge arms 1 to rotate around the hinge shaft 3 and open, thereby driving the two blades 2 to close together; when the drive shaft 9 retracts backward, the push member 11 disengages from the two hinge arms 1, and the two hinge arms 1 approach each other under the action of the return torsion spring 20 or an external elastic element, driving the two blades 2 to close and achieve cutting.

[0046] Furthermore, the pushing member 11 is cylindrical, with two radially opposing inclined pushing portions 12 at its front end. The two inclined pushing portions 12 are arranged vertically opposite each other, with their front ends (i.e., the ends closest to the hinge shaft 3) close together. Both inclined pushing portions 12 are located on the rear side of the hinge shaft 3 of the two hinge arms 1, i.e., on the side of the hinge shaft 3 closest to the power unit body 10. Each of the opposite sidewalls of the two hinge arms 1 is provided with a contacting inclined surface 13 that mates with the inclined pushing portion 12. The inclination angle of the contacting inclined surface 13 matches the inclination angle of the inclined pushing portion 12. When the drive shaft 9 advances forward, the inclined surface of the inclined pushing portion 12 slides into contact with the contacting inclined surface 13, converting the axial thrust into a component force perpendicular to the inclined surface direction. This smoothly pushes the rear ends of the two hinge arms 1 outward around the hinge shaft 3, while the front ends close inward, ultimately causing the blade to close for cutting. Of course, the piezoelectric sheet 501 can also be set on the bonding slope 13 in the same way, or one can be set on both the pushing component and the bonding slope 13.

[0047] Furthermore, a hinge seat 17 is integrally and coaxially provided at the front end of the cylinder body. Viewed radially along the cylinder body, the front view of the hinge seat 17 is an isosceles trapezoid, with its smaller end facing forward and used to mount the hinge shaft. Its larger end faces rearward and is integrally and fixedly connected to the front end face of the cylinder body. The two hinge arms 1 are located between the two hinge seats 17, meaning the rear ends of the two hinge arms 1 are sandwiched in the left and right gaps between the two hinge seats 17. The hinge shaft 3 passes through the shaft holes on the two hinge seats 17 and the two hinge arms 1 to achieve hinge connection with the two hinge seats 17. The hinge seats 17 and the hinge shaft 3 are detachably connected. Specifically, one end of the hinge shaft 3 is provided with a shoulder for limiting, and the other end is locked to the outer wall of the hinge seat 17 by a cotter pin or snap ring. When the blade 2 needs to be replaced, simply remove the cotter pin and pull out the hinge shaft 3 to remove the two hinge arms 1 along with the blade 2 as a whole, making maintenance quick and convenient.

[0048] When the drive shaft 9 moves forward, the inclined surface of the inclined push part 12 slides into contact with the mating inclined surface 13, converting the axial thrust into a component force perpendicular to the inclined surface direction. This smoothly pushes the rear ends of the two hinged arms 1 to open outward around the hinge shaft 3, while the front ends close inward, ultimately causing the blade 2 to close for cutting. The inclined surface engagement efficiently converts the axial thrust of the drive shaft 9 into the radial closing shearing force of the blade 2, with a force amplification factor of 3 to 5 times.

[0049] More specifically, the inclined pusher 12 includes an inclined platform 121 and a heat insulation pad 122 embedded in the inclined platform 121. The inclined platform 121 has mounting grooves 14, with the front ends of two mounting grooves 14 (i.e., the ends near the hinge shaft 3) approaching each other, so that the projection of the two mounting grooves 14 as a whole on the vertical plane forms a V-shape. The front end of the mounting groove 14 penetrates the front surface of the pusher 11, allowing the front end of the heat insulation pad 122 to contact the front area of ​​the inclined surface 13. The heat insulation pad 122 is embedded in the mounting groove 14, and when assembled, the outer surface of the heat insulation pad 122 is higher than the surface of the inclined platform.

[0050] The piezoelectric element 501 is specifically embedded in the recessed groove 1221 on the front end face of the heat insulation pad 122, enabling it to directly sense the change in reaction force at the contact slope 13. The signal acquisition point and the force application point almost coincide, further improving the real-time performance and accuracy of the detection. The heat insulation pad 122 effectively prevents the heat accumulated in the articulated arm 1 during the heating and cutting process from being transferred to the pushing component 11 and drive shaft 9 through the contact slope 13, preventing high-temperature damage to the cylinder seals and lubricating medium inside the power unit body 10.

[0051] More specifically, the side wall of the mounting groove 14 closest to the power unit body 10 (i.e., the rear side wall of the mounting groove 14) and the bottom surface of the mounting groove 14 together form a V-shaped groove 18, the tip of which points downwards and backwards. The heat insulation pad 122 is specifically a zirconia pad with a thickness of 8mm to 12mm. After being embedded in the mounting groove 14, its rear and lower sides are limited and supported by the V-shaped groove 18. When the drive shaft 9 pushes forward, the inclined surface 13 generates a backward thrust on the heat insulation pad 122. The V-shaped groove 18 can provide a stable forward support force for the heat insulation pad 122, effectively preventing the heat insulation pad 122 from loosening or shifting backwards during repeated pushing, ensuring the long-term stable and reliable position of the heat insulation pad 122 and the piezoelectric sheet 501 embedded therein, and guaranteeing the repeatability and durability of the first detection unit 500 under long-term high-frequency operation.

[0052] To achieve smooth cutting of thick-walled sprue, at least one of the two blades 2 is equipped with an electric heating element 5. This electric heating element 5 is arranged along the length of the blade 2, that is, the main heating part of the electric heating element 5 extends forward from the inside of the mounting base 7 to the front middle part of the blade 2, and its extension direction is consistent with the length direction of the blade 2. This arrangement ensures that the heat is evenly distributed along the longitudinal direction of the blade 2, avoiding the temperature gradient problem of overheating at the blade tip (which easily leads to softening of the cutting edge during annealing) and insufficient temperature at the blade root (which prevents the thick-walled sprue from softening sufficiently). This ensures that the temperature fluctuation of the entire cutting edge area is controlled within ±5℃, and the thick-walled sprue solidified material is softened by the thermal melting effect, significantly reducing the mechanical cutting resistance by about 30% to 50%, while extending the service life of the blade 2.

[0053] like Figure 2 As shown, the blade 2 is bent and inclined at one end toward the hinge axis 3 of the hinge arm 1, that is, the blade 2 has a bend angle in its middle and rear part in its extension direction (the actual center position is away from the workpiece), so that the working part of the front end of the blade 2 is tilted and offset relative to the axis of the hinge arm 1. This bending design allows the two blades 2 to perform cutting operations in an attitude parallel to the outer wall plane of the square shell workpiece, that is, the plate surface of the blade 2 is parallel to the side wall of the workpiece, and the bent section is used to avoid interference with the edge of the workpiece or adjacent wall, ensuring that the cutting edge can be closely attached to the root of the sprue for flat cutting, and the residual height after cutting can be controlled to be less than 0.2mm.

[0054] A cavity 201 is provided on the side wall of the blade 2 facing the bending direction. This cavity 201 is arranged along the length of the blade 2, that is, extending from the front cutting edge area of ​​the blade 2 to the rear mounting area. When the two blades 2 are assembled and in the closed state, the cavity 201 of the upper blade 2 and the cavity 201 of the lower blade 2 together form a cutting discharge channel, which extends along the length of the blade 2 and runs through it. During cutting, the sprue residue that is cut off is automatically discharged along the side of this discharge channel under the guidance of the arc-shaped walls of the upper and lower cavities 201, preventing the sprue residue from accumulating between the cutting edges and affecting the accuracy of secondary cutting.

[0055] The wall thickness of the cavity 201 gradually thins from both sides towards the blade closure line, thus forming a smooth arc-shaped transition surface on the inner wall of the cavity 201. This arc-shaped inner wall facilitates the smooth sliding of the cut sprue material along the arc surface, avoiding sprue jamming caused by sharp edges. It is particularly suitable for engineering plastic sprues with large cross-sectional thickness (up to 5mm or more) and tough material, improving the discharge smoothness rate to over 98%. At the same time, the cutting discharge channel can still ensure the smooth discharge of the broken part during secondary cutting. In conjunction with the supplementary cutting function of the ranging component 6, it effectively avoids the generation of defective products.

[0056] like Figures 7 to 10 As shown, the flipping pressure claw mechanism 300 specifically includes a base 301, a flipping pressure block 302 longitudinally hinged to the base 301, a flipping drive module 304 for driving the flipping pressure block 302 to a horizontal state, and a bracket 303 for fixing the flipping drive module 304. The base 301 is a quadrangular prism structure, with its width greater than its thickness. The upper surface of the base 301 is provided with a flipping groove 211 penetrating its peripheral sidewalls. From a top view, the base 301 has a C-shaped structure. The flipping pressure block 302 is longitudinally hinged to the edge of the flipping groove 211 via a flipping pivot 221.

[0057] The flipping pressure block 302 is a rectangular block structure with its long side pointing vertically upwards in its initial state. A buffer pad 222 is provided on the upper end of one side wall of the flipping pressure block 302 to elastically press against the surface of the workpiece when flipped to a horizontal position, preventing damage to the product. A downward-extending hinge extension 223 is located on one side of the lower end of the flipping pressure block 302, opposite to the horizontal outlet of the flipping shaft 221. Two hinge extensions 223 are provided, with each end of the flipping shaft 221 connected to one of the two hinge extensions 223, thus achieving a stable double-sided support hinge.

[0058] The second detection unit 600 is specifically a vibration sensor or piezoelectric element integrated on the flipping pressure block 302 (located on the inner wall of the buffer pad, embedded in the flipping pressure block). It is used to detect the contact vibration when the blade 2 closes and the cutting vibration when the sprue breaks during the cutting process. Under normal circumstances, there will be a clear cutting vibration wave when the cutting is complete, and there will also be a contact vibration wave when the blade 2 closes. The combination of these two vibrations can determine whether the sprue has been completely cut off. If the control unit only receives one vibration and there is no second vibration by the time the flipping pressure block 302 opens, it is determined that the cutting is not complete. This detection method starts from the vibration time domain characteristics and compares two different types of vibration waveforms, effectively avoiding misjudgments that may occur due to simply relying on the disappearance of pressure (for example, when the sprue is only partially cracked but not completely separated, the piezoelectric element may also output a pressure change signal due to deformation release), further improving the reliability of the cutting determination.

[0059] The flip drive module 304 includes a cylindrical linear drive assembly 3041 and a transmission connecting rod assembly 3042 that drives the flip pressure block 302 and the movable terminal 304a of the linear drive assembly 3041. The transmission connecting rod assembly 3042 is located at the upper end of the linear drive assembly 3041 and is encapsulated by a coaxial cylindrical structure 31, with a base 301 located at the upper end of the cylindrical structure 31.

[0060] The bottom surface of the flipping groove 211 is provided with a movable window for the transmission connecting rod assembly 3042 to push against the flipping pressure block 302 and flip to a horizontal state. The transmission connecting rod assembly 3042 includes a movable connecting rod 3a hinged to the hinge extension 223, and a central pivot 3b rotatably connected to the lower end of the movable connecting rod 3a. The lower end of the central pivot 3b is rotatably connected to the movable terminal 304a of the linear drive assembly 3041. The movable connecting rod 3a is a cylindrical structure, with its upper end located between the two hinge extensions 223 and hinged through a pivot shaft to achieve balanced force distribution.

[0061] The intermediate transfer seat 3b is axially slidably connected to the cylindrical structure 31. The movable terminal 304a of the linear drive assembly 3041 and the lower pivot point of the movable connecting rod 3a are coaxial with the cylindrical structure 31, while the upper pivot point of the movable connecting rod 3a is located on one side of the axis of the cylindrical structure 31. When the intermediate transfer seat 3b rises vertically under the push of the linear drive assembly 3041, the lower pivot point of the movable connecting rod 3a moves upward along the axis. Since the upper pivot point is off-center, the movable connecting rod 3a will sway laterally, thereby pushing upward against the hinged extension 223 and driving the flipping pressure block 302 to flip around the flipping shaft 221 toward the horizontal outlet direction of the flipping groove 211 to a horizontal state. This linkage-type flipping mechanism does not require a horizontal rotation radius and can complete the pressing action in a small space, with a compact structure.

[0062] The intermediate transfer seat 3b is a cylindrical structure whose outer diameter matches the inner diameter of the cylindrical structure 31, and the two slide together coaxially, forming a piston-like structure. This structure provides precise guidance and effectively prevents foreign objects from entering the upper sealing ring of the linear drive assembly 3041. The upper edge of the intermediate transfer seat 3b has an annular weir 3b1 surrounding the lower pivot point of the movable connecting rod 3a. The outer periphery of the annular weir 3b1 slides against the inner wall of the cylindrical structure 31, increasing the sliding contact length and further improving guiding stability. The upper surface of the annular cofferdam 3b1 is an annular conical surface that is concave and narrowed at the axis. This annular conical surface can guide foreign objects or dust that fall in into the annular cofferdam 3b1 to the inner side, preventing foreign objects from approaching and sticking to the inner wall of the cylindrical structure 31. This prevents foreign objects from entering the gap between the intermediate transfer seat 3b and the cylindrical structure 31, thereby avoiding scratching the inner wall of the cylindrical structure 31 and effectively extending the service life of the mechanism under high-frequency operation of more than 30 times per minute.

[0063] The lower end of the base 301 is integrally provided with a connecting pipe portion 3011. The upper outer wall of the cylindrical structure 31 has a recessed first positioning step adapted to the connecting pipe portion 3011. The inner wall of the connecting pipe portion 3011 and the first positioning step are respectively provided with mating internal and external threads. When assembled, the connecting pipe portion 3011 and the outer wall of the cylindrical structure 31 are flush with each other, resulting in a neat overall appearance without protruding structures, thus preventing scratching of surrounding cables or components during equipment operation.

[0064] The linear drive assembly 3041 is a small-diameter cylinder pointing vertically upwards. Using a small-diameter cylinder helps to further reduce the overall radial dimension. The upper end of the cylinder is coaxially connected to the cylindrical structure 31 via an adapter 3c. The outer walls of the upper and lower ends of the adapter 3c are respectively coaxially recessed with a second positioning step and a third positioning step. The upper end of the cylinder has a groove for the third positioning step to be inserted, and the two are threaded together. The second positioning step extends into the lower end of the cylindrical structure 31 and is threadedly connected to it.

[0065] When assembled, the outer walls of the cylinder, the cylindrical structure 31, and the adapter 3c are coaxial and flush with each other, giving the entire tilting drive module 304 a regular cylindrical shape. The adapter 3c has a channel for the movable terminal 304a of the linear drive assembly 3041 to pass through. A protective sleeve is provided in the channel and is coaxially fitted on the movable terminal 304a. This protective sleeve can effectively prevent external dust, sprue debris, etc. from entering the cylinder, preventing wear of the seals or piston jamming.

[0066] The bracket 303 includes a fixed base 3031, a column 3032 vertically fixed to the upper end of the fixed base 3031, and a fixed cross arm 3033 longitudinally hinged to the upper end of the column 3032. The linear drive assembly 3041 (i.e., a small-diameter cylinder) is detachably connected to one end of the fixed cross arm 3033 through a C-shaped bayonet and bolt engagement.

[0067] The present invention also provides a method for post-molding shaping of injection-molded products, using the above-mentioned post-molding shaping system for injection-molded products, including the following steps: S1: Place the shell workpiece with the sprue to be cut on the platform 200. The control unit controls the flipping drive module 304 of the four flipping pressure claw mechanism 300 to move. The movable terminal 304a of the linear drive component 3041 extends upward into the cylindrical structure 31, pushing the central rotating seat 3b to rise vertically along the inner cavity of the cylindrical structure 31. The movable connecting rod 3a moves upward accordingly and swings due to the deviation of its upper pivot point from the axis, thereby pushing upward against the hinge extension 223. This drives each flipping pressure block 302 to flip outward from the initial vertical state to the horizontal state around the flipping pivot 221. The buffer pad 222 presses against the surface of the shell workpiece and presses it firmly onto the platform 200. S2: The control unit controls the drive component 4 of the cutting mechanism to move. When the drive shaft 9 extends forward, the inclined surface of the inclined push part 12 slides into contact with the contacting inclined surface 13, smoothly pushing the rear end of the two hinge arms 1 to open outward around the hinge shaft 3 while the front end closes inward, driving the two blades 2 to cut the sprue on the outer wall of the shell workpiece. The electric heating element 5 heats the blades 2 before and during the cutting process to soften the thick-walled sprue condensate. The cut sprue condensate is automatically discharged laterally under the guidance of the cutting discharge channel formed by the upper and lower concave cavities 201. S3: During the cutting process, the piezoelectric sheet 501 embedded in the front end of the heat insulation pad 122 detects the change in force at the moment of sprue breakage and feeds it back to the control unit. The vibration sensor or piezoelectric sheet integrated on the flipping block 302 detects the contact vibration when the blade 2 closes and the cutting vibration when the sprue breaks and feeds it back to the control unit. S4: If the piezoelectric element 501 detects a change in force and the vibration sensor or the piezoelectric element simultaneously detects contact vibration and cutting vibration, the control unit determines that the cutting is complete. S5: If the distance measuring component 6 detects an abnormal distance value where the two blades 2 are not completely closed after cutting and feeds it back to the control unit, the control unit will then control the drive component 4 to perform a second cut. S6: After cutting is completed, the control unit controls the flipping drive module 304 to move, the movable terminal 304a retracts downward, the flipping pressure block 302 returns to the vertical state to make room, and the cut shell workpiece is removed. This method realizes automated closed-loop control of the cutting process, ensuring that the cutting quality of each product is consistent and controllable.

[0068] Furthermore, during the aforementioned cutting process, the ranging sensor 62, the vibration sensor or piezoelectric sheet 600 integrated on the flipping pressure block 202, and the piezoelectric sheet 501 within the heat insulation pad 122 all serve as feedback units for complete cutting. The detection data generated by each cutting action is fed back to the host computer in real time. The host computer 400 uploads the data to the cloud server 500 via the communication module for intelligent learning and model training. The system pre-enters all product types, material types, and their corresponding characteristic parameters such as hardness, melting temperature, heat distortion temperature, and toughness grade into the database, forming a process parameter library covering multi-dimensional material properties.

[0069] During actual processing, operators only need to input the product model or material grade, and the system can automatically retrieve the corresponding optimal cutting mode from the database, including key parameters such as the heating temperature curve of the electric heating element 5, the driving speed and thrust stroke of the drive component 4, and the trigger threshold for secondary cutting. One cutting mode can correspond to one set of cutting tools, or multiple sets of cutting tools can share the same mode. When switching cutting tools, the system automatically identifies the hardware ID of the paired electric heating element 5 and the pressure feedback device (i.e., the piezoelectric sheet in the inclined plane 13), and automatically pairs and binds the currently installed cutting tool with the cutting mode and algorithm parameters pre-stored in the database. There is no need for manual switching or parameter reset, realizing "one-click call and automatic adaptation" when switching between different products and materials, which greatly reduces changeover time and manual debugging errors, and is especially suitable for flexible production scenarios with multiple varieties and small batches.

[0070] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A post-molding shaping system for injection-molded products, characterized in that, The device includes a platform for placing a shell workpiece with a sprue to be cut, a clamping mechanism for pressing the shell workpiece onto the platform, and a cutting mechanism for cutting the sprue on the outer wall of the shell workpiece. The cutting mechanism includes two longitudinally hinged arms, a blade located at the front end of the hinged arms, and a drive assembly for driving the two hinged arms to open and close. There are four clamping mechanisms, each located at one of the four corners of the platform. The flipping clamping mechanism includes a flipping clamping block and a flipping drive module for driving the flipping clamping block to a clamping state. The system also includes: The first detection unit is disposed on the cutting mechanism and is used to detect the change in force at the moment of breakage of the sprue during the cutting process, and to determine whether the cutting is complete based on the change in force. The second detection unit is set on the flipping pressure block and is used to detect the contact vibration when the blade closes during the cutting process and the cutting vibration at the moment the sprue breaks, and to determine whether the cutting is complete based on the vibration signal. The control unit is connected to the first detection unit, the second detection unit, the drive component, and the flip drive module respectively, and is used to receive detection signals and control the operation of the drive component and the flip drive module.

2. The post-molding shaping system for injection molded products according to claim 1, characterized in that, The system further includes a third detection unit, which is disposed on one of the blades and is used to detect in real time the distance between the two blades or the relative position between the blade and the workpiece being cut. If the two blades do not completely close after a cut, the third detection unit sends an abnormal spacing signal to the control unit, which then controls the drive assembly to perform a second cut based on the abnormal spacing signal.

3. The post-molding shaping system for injection molded products according to claim 2, characterized in that, The third detection unit is a ranging component disposed on one of the blades. The ranging component includes a heat insulation substrate and a ranging sensor disposed on the heat insulation substrate. The ranging sensor is a laser displacement sensor or an infrared ranging sensor, and its detection end is directed toward the other blade or toward the top of the sprue located between the two blades.

4. The post-molding shaping system for injection molded products according to claim 3, characterized in that, The first detection unit is a piezoelectric sheet embedded in the pushing member of the drive assembly. The pushing member is used to push the two hinged arms to separate. When the cut reaches the break of the sprue, the pressure on the piezoelectric sheet disappears. The control unit determines that the cut is complete based on the pressure change.

5. The post-molding shaping system for injection molded products according to claim 4, characterized in that, The front end of the pushing member has two radially opposite inclined pushing parts, the two inclined pushing parts are arranged vertically opposite each other and their front ends are close to each other, and the opposite side walls of the two hinge arms are provided with fitting inclined surfaces that cooperate with the inclined pushing parts; the inclined pushing part includes an inclined platform and a heat insulation pad embedded in the inclined platform, and the piezoelectric sheet is embedded in the heat insulation pad and parallel to the fitting inclined surface.

6. The post-molding shaping system for injection molded products according to claim 3, characterized in that, The blade is bent and tilted towards one end of the hinge shaft, so that the working part of the front end of the blade is tilted and offset relative to the axis of the hinge arm; a cavity is provided on the side wall of the blade facing the bending direction, and when the two blades are closed, the two cavities together form a cutting and discharge channel that runs through the front and back; the ranging component is located on the discharge side of the cavity.

7. The post-molding shaping system for injection molded products according to claim 6, characterized in that, The wall thickness of the cavity gradually decreases from both sides toward the blade closure line, so that the inner wall of the cavity forms a smooth arc-shaped transition surface.

8. The post-molding shaping system for injection molded products according to claim 1, characterized in that, At least one of the two blades is provided with an electric heating element, which is arranged along the length of the blade and is used to heat the blade before and during cutting.

9. The post-molding shaping system for injection molded parts according to claim 1, characterized in that, The flipping pressure claw mechanism also includes a base, a support, and a cylindrical structure, and the flipping pressure block is longitudinally hinged to the base via a flipping pivot. The flipping drive module includes a vertical linear drive assembly and a transmission connecting rod assembly. The transmission connecting rod assembly is located at the upper end of the linear drive assembly and is encapsulated by the cylindrical structure. The upper end of the transmission connecting rod assembly is hinged to the lower end of the flipping pressure block. When the linear drive assembly drives the transmission connecting rod assembly to rise, it pushes the flipping pressure block to flip around the flipping axis to a horizontal state.

10. A method for post-molding shaping of injection-molded products, employing the post-molding shaping system for injection-molded products as described in any one of claims 3 to 9, characterized in that, Includes the following steps: S1: Place the shell workpiece with the sprue to be cut on the platform. The control unit controls the flipping drive module of the four flipping pressure claw mechanisms to drive each flipping pressure block to flip to a horizontal state and press the shell workpiece onto the platform. S2: The control unit controls the drive component of the cutting mechanism to close the two hinged arms and drive the two blades to cut the sprue on the outer wall of the shell workpiece. S3: During the cutting process, the first detection unit detects the change in force at the moment the sprue breaks and feeds it back to the control unit; the second detection unit detects the contact vibration when the blade closes and the cutting vibration when the sprue breaks and feeds it back to the control unit. S4: If the first detection unit detects a change in force and the second detection unit detects contact vibration and cutting vibration, the control unit determines that the cutting is complete; S5: If the third detection unit detects an abnormal gap signal that the two blades are not completely closed after cutting and feeds it back to the control unit, the control unit controls the drive component to perform a second cut again. S6: After the cutting is completed, the control unit controls the flipping drive module to flip each of the flipping blocks to the initial state and remove the cut shell workpiece.

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