A molding process applied to an injection mold

Abstract

The application relates to the technical field of die machining, and discloses a forming process applied to an injection mold, which comprises the following steps: S1, a milling machine and a lathe are used to implement rough machining on a mold blank to remove most of the machining allowance of the blank, and subsequent fine machining is conducted on the rough-machined blank through a grinding machine to control the size precision and surface flatness of the blank, so that a mold blank meeting the requirements of subsequent machining is finally obtained; and S2, the initial state of a mold blank closing surface is detected and confirmed, and the surface roughness of the closing surface and whether burrs, oxide skins and machining tool marks exist are checked. The forming process applied to the injection mold can effectively solve the problem in the prior art that trace ultrafine dust is generated in the laser polishing process, the dust is easy to accumulate in grooves and deep holes of the closing surface when the mold blank is horizontally placed, and the residual dust is sintered at high temperature in the subsequent laser scanning, so that secondary defects such as burns and micro-melt bumps occur on the closing surface.

Description

Technical Field

[0001] This invention relates to the field of mold processing technology, and more specifically to a molding process applied to injection molds. Background Technology

[0002] Injection molding, as an efficient and large-scale product manufacturing process, has been widely used in many industries such as electronics, automobiles, and home appliances. As the core equipment of this process, the performance and processing technology of injection molds directly determine the quality of molded products, production efficiency, and production costs.

[0003] The precision of the parting surface (mold surface) of an injection mold directly determines the molding quality of the injection molded product. If the parting surface has defects such as excessive surface roughness, burrs, or microcracks, it can easily lead to problems such as flash, overflow, or incomplete molding. With the increasing precision requirements of the precision injection molding industry, laser polishing technology has been widely used in the finishing process of the parting surface of injection molds due to its advantages such as high processing precision, small heat-affected zone, and adaptability to complex curved surfaces.

[0004] Currently, when laser polishing technology is used in the industry to process the mold parting surface of injection molds, the mold blank to be processed is placed horizontally in the laser processing platform. However, a small amount of ultrafine dust (originating from the vaporization and condensation of the material) is generated during the laser polishing process. When placed horizontally, this dust is easy to accumulate in the grooves and deep holes of the parting surface. The residual dust will be sintered by high temperature in the subsequent laser scanning, resulting in secondary defects such as burns and micro-melting nodules on the parting surface. Summary of the Invention

[0005] To address the aforementioned shortcomings of existing technologies, this invention provides a molding process for injection molds that effectively solves the problem that in existing technologies, a small amount of ultrafine dust (originating from material vaporization and condensation) is generated during laser polishing. When the mold blank is placed horizontally, this dust tends to accumulate in the grooves and deep holes of the mold parting surface. The residual dust will be sintered at high temperatures during subsequent laser scanning, leading to secondary defects such as burns and micro-melting nodules on the mold parting surface.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] This invention provides a molding process for injection molds, comprising:

[0008] S1. The mold blank is rough machined using a milling machine and a lathe to remove most of the machining allowance. Then, the rough machined blank is finished by a grinding machine to control the dimensional accuracy and surface flatness of the blank, and finally a mold blank that meets the requirements of subsequent processing is obtained.

[0009] S2. Inspect and confirm the initial state of the mold blank's mating surface, focusing on checking the surface roughness of the mating surface and whether there are burrs, oxide scale, and machining marks. Use a special fixture to accurately clamp and position the mold blank into the laser processing platform.

[0010] S3. Based on the physical properties of the mold blank material, the initial roughness value of the mold parting surface, and the preset target accuracy requirements, set the core parameters for laser processing, and generate the laser scanning path of the mold parting surface with the help of dedicated CNC programming software;

[0011] S4. Perform laser polishing on the mold surface. After the operation is completed, use high-pressure clean air to blow and clean the mold surface and the inside of the deep hole.

[0012] S5. A surface roughness meter is used to quantitatively detect the mold surface after purging and cleaning to obtain the actual surface roughness parameters of the mold surface. At the same time, the micro-morphology of the mold surface is observed by an optical microscope or a three-dimensional profile measuring instrument.

[0013] S6. Assemble the qualified mold parts according to the assembly requirements of the design drawings;

[0014] The special fixture in S2 includes a base assembled in the laser processing platform. A support plate is fixedly connected to the top of the base. Two support plates are provided and symmetrically distributed along the central surface of the base. A guide hole is provided in the support plate.

[0015] The base is rotatably connected to a bearing shaft via a bearing seat on its top, and the central axis of the bearing shaft coincides with the central axis of the guide hole. A bearing frame is fixedly connected to the outer circumference of the bearing shaft, and a U-shaped cavity for placing the mold blank is provided inside the bearing frame. A guide rod that fits against the inner wall of the guide hole is fixedly connected to the top of the bearing frame, and a bearing part for constraining the mold blank is provided inside the bearing frame.

[0016] The base is equipped with a drive component for driving the bearing shaft to rotate along its central axis.

[0017] Furthermore, the driving component includes a drive motor fixedly connected to the bottom of the base, and the output end of the drive motor is fixedly connected to a drive gear;

[0018] The end of the bearing shaft is fixedly connected to a driven gear that meshes with the driving gear.

[0019] Furthermore, a support frame is fixedly connected inside the bearing frame. The support frame has two sets and is symmetrically distributed from left to right along the center plane of the bearing frame. Each set of the support frame has two supports and is symmetrically distributed from top to bottom along the center plane of the bearing frame.

[0020] Furthermore, the supporting part includes a movable plate;

[0021] The movable plate is rotatably connected to the support frame by two pins located inside it and symmetrically distributed along the center plane of the movable plate. A torsion spring is fitted on the outer circumference of the pin. In the initial state, the torsion spring makes the movable plate and the support frame form a certain angle.

[0022] Furthermore, the two ends of the movable plate are respectively rotatably connected to constraint plates that penetrate the side wall of the support frame and extend into the U-shaped cavity. The bottom of the constraint plate near the base is designed with a slope. The two constraint plates on the side away from the base are connected by a connecting rod, and a wedge is fixedly connected to the outer circumference of the connecting rod.

[0023] Furthermore, the support frame is provided with a limiting plate that fits against the outer side of the mold blank, and there are two limiting plates that are symmetrically distributed along the central plane of the support frame. A movable rod assembly that penetrates the side wall of the support frame is fixedly connected inside the limiting plate. A wedge block two is fixedly connected to the end of the movable rod assembly, and the wedge block two is connected to the side wall of the support frame through a return spring set at its bottom.

[0024] Furthermore, the support frame is slidably connected to a counterweight block via a guide groove on its outer side, and the counterweight block is connected to the inner wall of the guide groove via a spring on its outer side. A compression rod that fits against the inclined surface of the wedge block is fixedly connected inside the counterweight block.

[0025] Furthermore, the support frame is slidably connected to a movable block via a groove formed inside it, and the movable block is connected to the inner wall of the groove via a spring two set on its outer side. Inside the movable block, a compression rod two is fixedly connected to fit against the inclined surface of the wedge two.

[0026] The technical solution provided by this invention has the following advantages compared with the prior art:

[0027] This invention comprises a support frame, a support shaft, and a support section. A drive component rotates the support shaft, switching the support frame from an initial tilted position to a vertical processing position. Metal chips and vaporized dust generated during laser grinding, under the vertical force of gravity, naturally fall along the complex structures such as grooves and deep holes on the mold surface, avoiding the accumulation of impurities that occurs with traditional horizontal placement. This design fundamentally prevents residual impurities from interacting with subsequent laser scanning, eliminating secondary defects such as burns and scratches on the mold surface and ensuring surface quality after grinding. Furthermore, during the rotation of the support frame, the gravity component of the counterweight drives the first extrusion rod, which in turn drives the connecting rod. Combined with the lever structure formed by the movable plate and the support frame (with a pin as the fulcrum and a torsion spring providing preload), the constraint plate adaptively switches. The switching process requires no additional power source, relying solely on the mechanical weight and elastic component transmission, adapting to the constraint requirements of the entire "feeding-processing-receiving" process. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without any creative effort.

[0029] Figure 1 This is a three-dimensional structural diagram of an embodiment of the present invention;

[0030] Figure 2 This is a schematic diagram of the three-dimensional separation structure of the base and support plate in an embodiment of the present invention;

[0031] Figure 3 This is a three-dimensional schematic diagram of the separated structure of the support frame and guide rod according to an embodiment of the present invention;

[0032] Figure 4 This is a schematic diagram of the three-dimensional separation structure of the support portion according to an embodiment of the present invention;

[0033] Figure 5 This is a schematic diagram of the planar structure of the support frame according to an embodiment of the present invention;

[0034] Figure 6 This is a cross-sectional view of the support frame according to an embodiment of the present invention;

[0035] Figure 7 This is a schematic diagram of the machining process of the mold blank according to an embodiment of the present invention;

[0036] Figure 8 This is a schematic diagram of the three-dimensional transformation structure of the support frame according to an embodiment of the present invention;

[0037] Figure 9 This is a schematic diagram of the three-dimensional state transformation structure of the constraint plate according to an embodiment of the present invention;

[0038] Figure 10 This is a flowchart of the injection mold forming process according to an embodiment of the present invention.

[0039] The labels in the diagram represent: 1. Base; 2. Support plate; 21. Guide hole; 3. Bearing shaft; 31. Driven gear; 4. Bearing frame; 41. Guide rod; 42. Support frame; 43. Limiting plate; 431. Movable rod assembly; 432. Wedge block two; 44. Counterweight block; 441. Pressing rod one; 45. Movable block; 451. Pressing rod two; 5. Bearing part; 51. Movable plate; 511. Pin shaft; 512. Torsion spring; 52. Constraint plate; 521. Connecting rod; 522. Wedge block one; 6. Driving component; 61. Drive motor; 62. Drive gear. Detailed Implementation

[0040] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. 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 scope of protection of the present invention.

[0041] The present invention will be further described below with reference to embodiments.

[0042] Example:

[0043] Please see Figures 1-10 This invention provides a technical solution: a molding process applied to injection molds, comprising:

[0044] S1. The mold blank is rough machined using a milling machine and a lathe to remove most of the machining allowance. Then, the rough machined blank is finished by a grinding machine to control the dimensional accuracy and surface flatness of the blank, and finally a mold blank that meets the requirements of subsequent processing is obtained.

[0045] S2. Inspect and confirm the initial state of the mold blank's mating surface, focusing on checking the surface roughness of the mating surface and whether there are burrs, oxide scale, and machining marks. Use a special fixture to accurately clamp and position the mold blank into the laser processing platform.

[0046] S3. Based on the physical properties of the mold blank material, the initial roughness value of the mold parting surface, and the preset target accuracy requirements, set the core parameters for laser processing, and generate the laser scanning path of the mold parting surface with the help of dedicated CNC programming software;

[0047] S4. Perform laser polishing on the mold surface. After the operation is completed, use high-pressure clean air to blow and clean the mold surface and the inside of the deep hole.

[0048] S5. A surface roughness meter is used to quantitatively detect the mold surface after purging and cleaning to obtain the actual surface roughness parameters of the mold surface. At the same time, the micro-morphology of the mold surface is observed by an optical microscope or a three-dimensional profile measuring instrument.

[0049] S6. Assemble the qualified mold parts according to the assembly requirements of the design drawings;

[0050] Among them, the special fixture in S2 includes a base 1 assembled in the laser processing platform, a support plate 2 fixedly connected to the top of the base 1, and two support plates 2 are provided and symmetrically distributed along the central surface of the base 1. A guide hole 21 is opened in the support plate 2.

[0051] The base 1 is rotatably connected to the bearing shaft 3 via a bearing seat on its top, and the central axis of the bearing shaft 3 coincides with the central axis of the guide hole 21. The outer circumferential surface of the bearing shaft 3 is fixedly connected to the bearing frame 4, and the bearing frame 4 is provided with a U-shaped cavity for placing the mold blank. The top of the bearing frame 4 is fixedly connected to the guide rod 41 that fits against the inner wall of the guide hole 21. The bearing frame 4 is provided with a bearing part 5 for constraining the mold blank.

[0052] The base 1 is equipped with a drive component 6 for driving the bearing shaft 3 to rotate along its central axis.

[0053] The driving component 6 includes a drive motor 61 fixedly connected to the bottom of the base 1, and the output end of the drive motor 61 is fixedly connected to a drive gear 62.

[0054] The end of the bearing shaft 3 is fixedly connected to a driven gear 31 that meshes with the driving gear 62.

[0055] The support frame 4 is fixedly connected to the bearing frame 4. There are two sets of support frames 42, which are symmetrically distributed on the left and right sides along the center plane of the bearing frame 4. Each set of support frames 42 has two, which are symmetrically distributed on the top and bottom along the center plane of the bearing frame 4.

[0056] The support unit 5 includes a movable plate 51;

[0057] The movable plate 51 is rotatably connected to the support frame 42 by a pin 511 set inside it. There are two pins 511 and they are symmetrically distributed along the center plane of the movable plate 51. A torsion spring 512 is sleeved on the outer circumference of the pin 511. In the initial state, the torsion spring 512 makes the movable plate 51 and the support frame 42 form a certain angle.

[0058] The two ends of the movable plate 51 are respectively rotatably connected to constraint plates 52 that penetrate the side wall of the support frame 4 and extend into the U-shaped cavity. The bottom of the constraint plate 52 on the side closer to the base 1 is designed with a slope. The two constraint plates 52 on the side away from the base 1 are connected by a connecting rod 521. A wedge block 522 is fixedly connected to the outer circumference of the connecting rod 521.

[0059] The support frame 4 is provided with a limiting plate 43 that fits against the outer side of the mold blank. There are two limiting plates 43 that are symmetrically distributed along the center plane of the support frame 4. A movable rod assembly 431 that penetrates the side wall of the support frame 4 is fixedly connected inside the limiting plate 43. A second wedge block 432 is fixedly connected to the end of the movable rod assembly 431. The second wedge block 432 is connected to the side wall of the support frame 4 through a return spring at its bottom.

[0060] The support frame 4 is slidably connected to a counterweight 44 through a guide groove on its outer side, and the counterweight 44 is connected to the inner wall of the guide groove through a spring on its outer side. A compression rod 441 that fits against the inclined surface of the wedge block 522 is fixedly connected inside the counterweight 44.

[0061] The support frame 4 is slidably connected to the movable block 45 through a groove opened inside it, and the movable block 45 is connected to the inner wall of the groove through a spring 2 set on its outer side. The movable block 45 is fixedly connected to the compression rod 451 that fits against the inclined surface of the wedge block 432.

[0062] The principle and advantages of this molding process applied to injection molds:

[0063] Under actual processing conditions, the support frame 4 maintains its initial posture, i.e., it maintains a preset tilt angle with the plane of the base 1, and is arranged at an inclination, through the guide hole 21 inside the support plate 2. At the same time, the pin 511 inside the movable plate 51 is kept in an inclined state under the elastic pre-tightening action of the strong torsion spring 512, ultimately achieving a differentiated layout of the double constraint plates 52: the constraint plate 52 on the side closer to the base 1 is embedded inside the U-shaped cavity of the support frame 4, providing an initial support base for the mold blank; the constraint plate 52 on the side farther from the base 1 is outside the U-shaped cavity, reserving mechanical stroke for subsequent switching of working states.

[0064] The external conveying device transports the mold blank to be ground to the feeding end of the support frame 4. During the feeding process, it is necessary to ensure that the surface of the mold blank to be processed faces the base 1. Because the support frame 4 is arranged at a preset angle, the constraint plate 52 embedded in the U-shaped cavity and the inner wall of the U-shaped cavity work together to form an open positioning space. When the mold blank enters the U-shaped cavity, under the action of its own gravity along the inclined direction, it gradually falls into the positioning space and completes the initial positioning constraint, thus preventing the blank from shifting.

[0065] After the material is loaded, the external transfer device is removed from the working area. Simultaneously, the drive motor 61 in the drive unit 6 drives its output end drive gear 62 to rotate at a constant speed. Through the meshing transmission between the drive gear 62 and the driven gear 31 at the end of the bearing shaft 3, the rotational torque is transmitted to the bearing shaft 3, causing the bearing shaft 3 to rotate around its central axis. This drives the bearing frame 4 to work with the guide rod 41 to complete the rotational movement along the guide hole 21 of the support plate 2, providing a power basis for subsequent limit and constraint switching.

[0066] As the inclination angle between the support frame 4 and the base 1 gradually increases until the preset sliding angle of the movable block 45 is reached, the component of the gravity of the movable block 45 along the slide groove gradually overcomes the sum of the friction between the movable block 45 and the slide groove and the elastic resistance of the second spring, causing the movable block 45 to undergo linear displacement along the slide groove. During the downward movement of the movable block 45, the second extrusion rod 451, which is fixed to it, applies an extrusion force to the inclined surface of the second wedge block 432. This extrusion force is transmitted through the inclined surface of the second wedge block 432 and converted into a thrust along the axis of the movable rod assembly 431, driving the limiting plate 43 to move towards the side wall of the mold blank until the two sets of limiting plates 43 are completely in contact with the side wall of the mold blank, thus achieving the initial limiting constraint on the blank.

[0067] As the support frame 4 continues to rotate, the angle between it and the base 1 further increases (but does not reach a vertical state), and the gravitational component of the movable block 45 is further increased. Because the limit plate 43 is pre-installed with a rubber buffer layer on the contact surface with the blank, under the continuous force of the extrusion rod 451 and the wedge 432, the limit plate 43 compresses the rubber buffer layer, and further increases the limiting and fastening force on the mold blank through elastic deformation. At this time, the movable block 45 reaches a state of force balance and stops sliding.

[0068] When the support frame 4 continues to rotate to a near-vertical state (not completely vertical), the component of the weight of the counterweight 44 along the guide groove overcomes the sum of the friction between the counterweight 44 and the guide groove and the elastic resistance of the spring, causing the counterweight 44 to undergo linear displacement along the guide groove. The pressing rod 441, which is fixed to the counterweight 44, applies a pressing force to the inclined surface of the wedge 522. This pressing force drives the wedge 522, in conjunction with the connecting rod 521, to move the constraint plate 52 on the side away from the base 1 into the U-shaped cavity. At the same time, the movable plate 51 and the support frame 42 form a lever transmission structure. Under the pushing action of the constraint plate 52 on the side away from the base 1, the constraint plate 52 on the side close to the base 1 is forced to exit the U-shaped cavity until the wedge 522 moves to its maximum stroke, completing the switching of the working state of the constraint plate 52: the constraint plate 52 on the side close to the base 1 completely exits the U-shaped cavity, and the constraint plate 52 on the side away from the base 1 is embedded in the U-shaped cavity, realizing the replacement of the constraint plate 52.

[0069] It is worth noting that both the counterweight 44 and the movable block 45 are made of high-density materials and have a large mass. Furthermore, the coefficient of friction between the counterweight 44 and the guide groove is much greater than that between the movable block 45 and the slide groove. Therefore, when the support frame 4 rotates to the preset sliding angle of the movable block 45, the movable block 45 can overcome the friction between itself and the slide groove to slide, while the counterweight 44 remains stationary due to frictional constraints. During the stage when the support frame 4 rotates from its initial position to the preset sliding angle of the movable block 45, the mold blank is supported by the constraint plate 52 near the base 1, and gravity mainly acts on this constraint plate 52. When the support frame 4 rotates from the preset angle to a near-vertical state, the weight of the mold blank is mainly supported by the inner wall of the U-shaped cavity, and the two sets of symmetrically arranged limiting plates 43 work together to achieve limiting constraints, effectively preventing the mold blank from detaching from the U-shaped cavity.

[0070] When the support frame 4 rotates to the vertical position, the constraint plate 52 completes the working state switch. The constraint plate 52, which originally blocked the surface of the mold blank to be processed, completely exits the processing area, and the laser processing unit starts the grinding process on the surface of the mold blank to be processed.

[0071] During laser polishing, laser energy rapidly heats a tiny area on the workpiece surface to its vaporization point. Some material vaporizes directly, forming tiny solid particles upon cooling. Incompletely vaporized molten material splashes due to surface tension and airflow, forming solid dust. Because the mold blank is placed vertically, gravity exerts a downward pull on the dust. The dust detaches from the workpiece surface and falls vertically, completely avoiding the accumulation of dust on the top or in the grooves of the blank when placed horizontally. This effectively prevents residual impurities from interacting with the laser during subsequent laser scanning, thus avoiding secondary defects such as burns and micro-melting nodules on the mold surface, significantly improving the polishing quality and processing accuracy of the mold.

[0072] It is worth noting that the limiting plate 43 has pre-set inclined surfaces on both sides, which form a specific gap between the inclined surfaces and the side wall of the mold blank to provide machining clearance. This design prevents the limiting plate 43 from completely fitting against the side wall of the mold blank, thus effectively avoiding direct laser beam irradiation of the limiting plate 43 when the laser processing unit grinds the edge area of ​​the mold blank near the limiting plate 43. This prevents damage to the limiting plate 43 due to laser energy and ensures the structural integrity and subsequent functional stability of the limiting plate 43.

[0073] After the mold blank grinding operation is completed, the laser processing unit leaves the processing area. Simultaneously, the drive component 6 drives the bearing shaft 3 to rotate along the original rotation direction again, causing the bearing frame 4 to continue to deflect in the same direction from the vertical state.

[0074] When the support frame 4 rotates to the preset reset angle of the movable block 45, the second spring connected to the movable block 45 releases its elastic reset force. Under the action of this elastic force, the movable block 45 completes the guided reset along the slide groove. As the movable block 45 resets, the degree of extrusion contact between the second extrusion rod 451 and the second wedge 432 connected to it gradually decreases. At the same time, under the action of the elastic driving force of the reset spring, the second wedge 432 drives the limiting plate 43 to gradually reset along the axis of the movable rod group 431 until the limiting plate 43 returns to its initial position, releasing the limiting constraint on the mold blank.

[0075] There are pre-set differences in the coefficient of friction between the slide and the movable block 45, and between the guide groove and the counterweight block 44 (the coefficient of friction between the slide and the movable block 45 is much smaller than that between the guide groove and the counterweight block 44). Therefore, during the reset process of the movable block 45, the counterweight block 44 remains stationary due to the constraint of greater frictional force and does not reset temporarily. At this stage, since the limiting plate 43 has been released from constraint, the supporting function of the mold blank is undertaken by the constraint plate 52 on the side away from the base 1.

[0076] When the support frame 4 continues to deflect to the preset feeding angle, the spring connected to the counterweight 44 releases its elastic restoring force. Under the action of this elastic force, the counterweight 44 completes the guided reset along the guide groove. As the counterweight 44 resets, the pressing rod 441 connected to it gradually releases its pressing and limiting effect on the wedge 522. At the same time, under the elastic pre-tightening force of the strong torsion spring 512, the lever structure formed by the movable plate 51, the constraint plate 52, and the support frame 42 starts the reset action, pushing the constraint plate 52 away from the base 1 to exit the U-shaped cavity, and the constraint plate 52 close to the base 1 to re-embed into the U-shaped cavity, completing the reset switch of the working state of the constraint plate 52.

[0077] After the constraint plate 52 is reset, the constraint plate 52 on the side away from the base 1 completely loses its supporting function for the mold blank, and the mold blank is released from the constraint state. At this time, the external material receiving unit accurately docks with the outlet of the U-shaped cavity of the bearing frame 4 and automatically collects the processed mold blank, thus completing the whole process of grinding the mold blank's mating surface.

[0078] During the material receiving process, the angle control of the support frame 4 and the positioning design of the receiving unit ensure that the processed mold blank always maintains an upward-facing mold-closing surface. This design avoids contact friction between the mold-closing surface and the receiving equipment or other components during the material receiving process, effectively preventing secondary wear on the mold-closing surface. Furthermore, the constraint plates 52 are all made of smooth materials with a high surface finish, low surface friction coefficient, and no sharp protrusions. This material selection avoids scratches or wear on the polished mold-closing surface caused by the constraint plates 52 during contact with the mold blank's mold-closing surface (especially during the support and reset stages), ensuring the machining accuracy and surface quality of the mold-closing surface.

[0079] The present invention employs a support frame 4, a support shaft 3, and a support part 5, which has the following advantages:

[0080] Firstly, dust is autonomously discharged, avoiding secondary defects on the mold parting surface. Driven by the drive component 6 (drive motor 61 + gear meshing transmission), the bearing shaft 3 rotates, causing the bearing frame 4 to switch from its initial tilted posture to a vertical processing posture. Metal chips and vaporized dust generated during laser polishing, under the vertical force of gravity, naturally fall along the complex structures of the mold parting surface, such as grooves and deep holes, avoiding the accumulation of impurities that occurs with traditional horizontal placement. This design fundamentally prevents residual impurities from interacting with subsequent laser scanning, eliminating secondary defects such as burns and scratches on the mold parting surface and ensuring surface quality after polishing.

[0081] Secondly, the constraint plate 52 adaptively switches its working state to meet the needs of the entire processing flow. During the rotation of the support frame 4, the gravity component of the counterweight block 44 drives the extrusion rod 441, and the extrusion wedge block 522 drives the connecting rod 521 for transmission. Combined with the lever structure formed by the movable plate 51 and the support frame 42 (with the pin shaft 511 as the fulcrum and the torsion spring 512 providing the reset preload), the constraint plate 52 achieves adaptive switching from "embedding into the U-shaped cavity to support the blank (loading stage) - exiting the U-shaped cavity to avoid processing (grinding stage) - resetting to support and assist in unloading (receiving stage)". The switching process does not require an additional power source, relying only on the mechanical weight and elastic component transmission, adapting to the constraint requirements of the entire "loading-processing-receiving" process.

[0082] Thirdly, the flexible limiting mechanism and machining avoidance design protect the mold and fixture structure. The limiting plate 43 has a built-in rubber buffer layer, which absorbs the clamping force through elastic deformation, avoiding damage to the side wall of the mold blank caused by rigid clamping. At the same time, the limiting plate 43 has a pre-set inclined surface machining avoidance space on both sides. When the laser scans the edge area of ​​the mold closing surface, it can avoid the laser beam from directly hitting the fixture (bearing frame 4, limiting plate 43), preventing the fixture from annealing and deformation due to laser heat, and ensuring the stability of the fixture structure and the machining accuracy of the blank edge.

[0083] Fourthly, the finished product receiving process is protected, avoiding secondary damage to the mold closing surface. During the receiving stage, when the support frame 4 returns to the unloading angle, the constraint plate 52 switches to the "release posture" through the reset force of the torsion spring 512. Under the action of gravity, the mold blank detaches from the U-shaped cavity, and the external receiving unit precisely connects with the outlet of the U-shaped cavity, ensuring that the blank always maintains the mold closing surface facing upwards, avoiding collision between the mold closing surface and the equipment during the receiving process. At the same time, the constraint plate 52 uses a high surface finish material with a low coefficient of friction to avoid scratches or wear when in contact with the mold closing surface, thoroughly protecting the surface quality of the already polished mold closing surface.

[0084] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions will not cause the essence of the corresponding technical solutions to deviate from the protection scope of the technical solutions of the embodiments of the present invention.

Claims

1. A fixture used in injection molding processes, characterized in that, include: A base is assembled inside a laser processing platform. A support plate is fixedly connected to the top of the base. Two support plates are provided and symmetrically distributed along the central surface of the base. Guide holes are provided in the support plates. The base is rotatably connected to a bearing shaft via a bearing seat on its top, and the central axis of the bearing shaft coincides with the central axis of the guide hole. A bearing frame is fixedly connected to the outer circumference of the bearing shaft, and a U-shaped cavity for placing the mold blank is provided inside the bearing frame. A guide rod that fits against the inner wall of the guide hole is fixedly connected to the top of the bearing frame, and a bearing part for constraining the mold blank is provided inside the bearing frame. The base is provided with a drive component for driving the bearing shaft to rotate along its central axis; The support frame is fixedly connected inside the bearing frame. The support frame is provided in two sets and is symmetrically distributed from left to right along the center plane of the bearing frame. Each set of the support frame has two support frames and is symmetrically distributed from top to bottom along the center plane of the bearing frame. The supporting part includes a movable plate; the movable plate is rotatably connected to the support frame by a pin provided inside it, and there are two pins symmetrically distributed along the center plane of the movable plate. A torsion spring is sleeved on the outer circumference of the pin. In the initial state, the torsion spring makes the movable plate and the support frame form a certain angle. The movable plate is rotatably connected to two ends of a constraint plate that penetrates the side wall of the support frame and extends into the U-shaped cavity. The bottom of the constraint plate on the side closer to the base is designed with a slope. The two constraint plates on the side away from the base are connected by a connecting rod, and a wedge is fixedly connected to the outer circumference of the connecting rod. The support frame is provided with a limiting plate that fits against the outer side of the mold blank. There are two limiting plates that are symmetrically distributed along the center plane of the support frame. A movable rod group that penetrates the side wall of the support frame is fixedly connected inside the limiting plate. A wedge block two is fixedly connected to the end of the movable rod group. The wedge block two is connected to the side wall of the support frame through a return spring set at its bottom. The support frame is slidably connected to a counterweight block via a guide groove on its outer side, and the counterweight block is connected to the inner wall of the guide groove via a spring on its outer side. A compression rod that fits against the inclined surface of the wedge block is fixedly connected inside the counterweight block. The support frame is slidably connected to a movable block through a groove inside it, and the movable block is connected to the inner wall of the groove through a spring two set on its outer side. A compression rod two that fits against the inclined surface of the wedge two is fixedly connected inside the movable block. Both the counterweight and the movable block are made of high-density materials and have a large mass. The coefficient of friction between the counterweight and the guide groove is much greater than that between the movable block and the slide. When the support frame rotates to the preset sliding angle of the movable block, the movable block can overcome the friction between it and the slide to slide, while the counterweight remains stationary due to the constraint of friction.

2. The fixture for injection molding process according to claim 1, characterized in that: The driving component includes a drive motor fixedly connected to the bottom of the base, and the output end of the drive motor is fixedly connected to a drive gear. The end of the bearing shaft is fixedly connected to a driven gear that meshes with the driving gear.

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