A multi-step split core mold

Abstract

The utility model discloses a kind of multi-step split-mold core-pulling moulds, including top plate, runner plate, upper die, lower die, backing plate, bottom plate sequentially arranged from top to bottom, a pair of support plate is arranged between the backing plate and bottom plate, and the left and right sides are supported to both, the runner plate is provided with the upper pull rod that can pull upper die downwards, the lower die core is provided with the male die insert;The male die insert is provided with first core-pulling assembly, and the lower die both sides are respectively provided with the limiting assembly for limiting the moving distance of lower die.The mould is designed by mechanical linkage, and the core-pulling and stripping of injection molding product are completed by the action of multi-step split-mold, without using any oil cylinder auxiliary operation, effectively control the use space of mould, achieve the purpose of energy saving and environmental protection.

Description

Technical Field

[0001] This utility model relates to the field of injection mold technology, and in particular to a multi-step parting and core-pulling mold. Background Technology

[0002] Injection molds are tools used for molding plastics. They inject molten plastic into a closed cavity, and after cooling and solidification, produce a plastic product that perfectly matches the shape of the cavity. It is a key piece of equipment in the plastic injection molding process, determining important characteristics such as the shape, size, precision, and surface quality of the plastic product. Demolding thin-walled products has always been a difficult problem to solve in injection molding, mainly because thin-walled products are prone to damage during demolding, such as… Figure 1 As shown, especially for thin-walled products with multiple grooves (a), the multi-groove structure itself is not easy to demold. Furthermore, when the inner undercut (b) requires a core-pulling structure, demolding cannot be achieved directly through the parting action of the upper and lower molds. The demolding action design for such products has extremely strict requirements. Existing designs generally employ a multi-core-pulling structure, using multiple hydraulic cylinders to drive the core-pulling structure for demolding, avoiding interference during subsequent mold parting, and then removing the product through the parting between the upper and lower molds. This existing design has two drawbacks: first, the multi-cylinder structure significantly increases energy consumption and results in an excessively large injection mold footprint, making installation difficult; second, while the core-pulling design is easy to implement for external core-pulling structures, it complicates the mold structure for internal undercut core-pulling structures, making the mold difficult to manufacture and hindering precision control. Therefore, we need an energy-efficient injection mold that can automatically demold and pull cores in stages, providing a new design direction for mold design of thin-walled products with internal undercut structures. Utility Model Content

[0003] The purpose of this invention is to address the shortcomings of existing technologies by proposing a multi-step parting and core-pulling mold.

[0004] To achieve the above objectives, a multi-step parting and core-pulling mold includes, from top to bottom, a top plate, a runner plate, an upper mold, a lower mold, a backing plate, and a bottom plate. A pair of support plates, separate on the left and right sides and supporting both, are provided between the backing plate and the bottom plate. The area between the support plates forms an ejector space. A fixed plate and an ejector pin plate are movably arranged vertically within the ejector space. The upper mold has an upper mold core, and the lower mold has a lower mold core. The runner plate has a downward-pointing upper pull rod that can pull the upper mold. The lower end of the upper pull rod has an upper pull rod head. The upper mold is equipped with a mechanism that allows the upper pull rod to move and controls the movement of the upper pull rod head. The upper pull rod hole restricts the movement of the mold. The lower mold core is provided with a punch insert. The punch insert is provided with a first core-pulling assembly, which includes a movable insert provided at the undercut position of the punch insert corresponding to the injection molded product. The pad is provided with an insert block that extends into the punch insert. The insert block is provided with a first inclined surface that slopes downward and outward. The movable insert is movably connected along the first inclined surface. Limiting components that restrict the movement distance of the lower mold are provided on both sides of the lower mold. The limiting components include a push block provided on one side of the lower mold and a push strip provided on one side of the ejector plate or fixed plate and extending towards the push block. A limiting block that restricts the stroke of the push block is provided on the pad.

[0005] The mold features a multi-step parting structure. The first stage involves the top plate and runner plate separating, removing the sprue material. The second stage involves the runner plate pulling the upper mold via a pull rod, thus causing the upper mold to separate. The third stage involves the injection molding machine driving the ejector plate, which, through a limiting assembly, drives the lower mold to separate. During this stage, the first core-pulling assembly performs the inner core-pulling operation of the molded product. The fourth stage involves the ejector plate continuing to move, ejecting the molded product through ejector pins. Through its mechanically linked design, the mold completes core-pulling and demolding of the injection molded product in a multi-step parting motion, eliminating the need for any hydraulic cylinders. This effectively controls the mold's usable space and achieves energy conservation and environmental protection.

[0006] Preferably, the first core-pulling assembly has a first slide rail with the same slope on the first inclined surface, the movable insert has a first slide groove that matches the first slide rail, the insert block has a first guide block perpendicular to the first inclined surface on both sides, and the punch insert has a first guide groove that corresponds to the first guide block and is perpendicular to the first inclined surface.

[0007] During the mold separation process, the movable insert moves inward under the traction of the first slide rail and guided by the first guide groove. The movable insert detaches from the injection molded product, completing the inner core pulling operation and realizing automatic core pulling through mechanical linkage.

[0008] Preferably, the limiting component has a limiting guide groove in the limiting block to accommodate the push bar and guide the push bar vertically upward. The lower mold has mounting grooves on both sides. The push block is movably disposed in the mounting groove. A limiting reset spring is provided in the mounting groove to support the push block. The limiting block has a limiting groove to restrict the upward movement of the push block.

[0009] The limit reset spring can push the end of the push block out of the mounting groove, so that the push bar can push the push block to drive the lower mold to separate. The limit groove restricts the stroke of the push block and controls the stroke of the lower mold to separate.

[0010] Preferably, the outer end of the push block is provided with a shrinking slope that slopes downwards and outwards, the limiting groove is provided with a shrinking guide surface corresponding to the shrinking slope, and the fixing plate is provided with multiple movable ejector pins whose ends can pass through the punch insert.

[0011] The shrinkage ramp and shrinkage guide surface are set to guide the movement. When the push block moves to the end of its stroke, the push bar continues to apply pressure, which can drive the push block to retract into the mounting groove. The push bar can continue to move forward, and the ejector plate drives the movable ejector to eject the injection molded product.

[0012] Preferably, the pad is provided with an upward pull rod, the upper end of the pull rod is provided with a pull rod head, and the lower mold is provided with a pull rod hole that allows the pull rod to move and limits the movement stroke of the pull rod head.

[0013] To ensure the stability of the lower die's position after the stroke reaches its end, a pull rod and a pull rod hole are designed to limit the lower die's stroke end point, which also facilitates the push bar to drive the push block back into the mounting slot.

[0014] Preferably, the punch insert is provided with a second core-pulling assembly on each of its left and right sides. The second core-pulling assembly includes a transverse slider disposed on either the left or right side of the punch insert and slidable left and right, and a transverse core-pulling component fixedly connected to the transverse slider. The transverse slider is provided with a second inclined surface that slopes outward and downward. The upper die is provided with a second guide surface corresponding to the second inclined surface. The upper die is provided with a slider guide rod with the same slope and direction as the second inclined surface. The transverse slider is provided with a guide through hole corresponding to the slider guide rod. The two sides of the transverse slider are respectively provided with a second slide rail with the same sliding direction. The lower die is provided with a second slide groove that matches the second slide rail.

[0015] The second core-pulling component allows for external core pulling on the left and right sides of the injection molded product. The horizontal slider moves outward under the traction of the slider guide rod when the upper mold is parted, driving the horizontal core-pulling component to pull the core. The core-pulling operation is achieved through mechanical linkage.

[0016] Preferably, the lower mold and the second inclined surface corresponding to the bottom of the horizontal slider are respectively provided with multiple wear-resistant plates, the bottom of the horizontal slider is provided with a horizontal positioning groove, the lower mold is provided with a horizontal positioning block that matches the horizontal positioning groove, and the horizontal positioning block and the lower mold are elastically connected in a retractable manner.

[0017] Considering that the horizontal slider can be used for partial core pulling operations or for covering the entire side of the injection molded product during mold parting, when the horizontal slider is large, the friction during mold parting and mold closing can easily cause wear on the surface of the horizontal slider. Therefore, wear-resistant plates are set to protect the horizontal slider. The retractable horizontal positioning block, in conjunction with the horizontal positioning groove, can accurately position the horizontal slider during mold closing.

[0018] Preferably, a third core-pulling assembly is provided on both the front and rear sides of the punch insert. The third core-pulling assembly includes a longitudinal slider disposed on either the front or rear side of the punch insert and capable of sliding forward, backward, or obliquely. A longitudinal core-pulling part is provided at the end of the longitudinal slider near the punch insert. The longitudinal slider is provided with an oblique sliding groove that slopes downward outward. The upper die is provided with an oblique guide block corresponding to the oblique sliding groove. A third slide rail is provided on both sides of the longitudinal slider in the same direction as its sliding. The lower die is provided with a third sliding groove that matches the third slide rail.

[0019] The third core-pulling component allows for external core pulling on the front and rear sides of the injection molded product. The longitudinal slider moves outward under the traction of the inclined guide block when the upper mold is parted, driving the longitudinal core-pulling part to pull the core. The core-pulling operation is achieved through mechanical linkage.

[0020] Preferably, the longitudinal slider has a mounting hole on the side near the punch insert, and a core-pulling return spring for supporting the longitudinal slider and the punch insert is provided in the mounting hole. The bottom of the longitudinal slider has a longitudinal positioning groove, and the lower die has a longitudinal positioning block that matches the longitudinal positioning groove. The longitudinal positioning block and the lower die are elastically connected in a telescopic manner.

[0021] Considering that the longitudinal slider is used for partial core pulling of injection molded products, the longitudinal slider is suitable for a small slider type. The core pulling return spring can help drive the longitudinal slider to move outward, while the telescopic longitudinal positioning block and the longitudinal positioning groove can accurately position the position of the transverse slider when the mold is closed.

[0022] Preferably, the fixed plate is provided with a buffer spring that passes through the pad and forms a support between the fixed plate and the lower mold, and the bottom of the ejector plate is provided with multiple anti-collision pads.

[0023] The buffer spring can cushion the movement of the ejector plate and drive the ejector plate to reset. The anti-collision pad prevents the ejector plate from directly impacting the base plate when it resets, thus mitigating the impact and preventing the moving ejector from being affected by excessive vibration over a long period of time, which could affect the positional accuracy.

[0024] Compared with the prior art, the beneficial effects of this utility model are:

[0025] This invention features a multi-step mold-parting structure. In the first stage, the top plate and runner plate separate, removing the sprue material. In the second stage, the runner plate pulls the upper mold via a pull rod, thus causing the upper mold to separate. In the third stage, the injection molding machine drives the ejector plate to move, which in turn drives the lower mold to separate via a limiting component. During this stage, as the lower mold separates, the first core-pulling component performs the inner core-pulling operation of the injection-molded product. In the fourth stage, the ejector plate continues to move, ejecting the injection-molded product through ejector pins. Through a mechanically linked design, the mold completes the core-pulling and demolding of the injection-molded product in a multi-step mold-parting action, eliminating the need for any hydraulic cylinders. This effectively controls the mold's usable space, achieving energy conservation and environmental protection. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the accompanying drawings used in the embodiments will be briefly introduced below.

[0027] Figure 1 This is a schematic diagram of the injection-molded product structure, which is the background technology of this utility model.

[0028] Figure 2 This is a schematic diagram of the structure of this utility model.

[0029] Figure 3 This is a partial structural schematic diagram of the present invention.

[0030] Figure 4 This is a schematic diagram of the upper mold structure of this utility model.

[0031] Figure 5 This is a schematic diagram of the lower mold in the closed state of this utility model.

[0032] Figure 6 This is a partial structural schematic diagram of the present invention.

[0033] Figure 7 This is a partial structural diagram of the second core-pulling component of this utility model in the mold-parting state.

[0034] Figure 8 This is a partial structural schematic diagram of the present invention.

[0035] Figure 9 This is a partial structural schematic diagram of the present invention.

[0036] Figure 10 This is a partial structural diagram of the third core-pulling component of this utility model in the mold-closed state.

[0037] Figure 11 This is a partial structural diagram of the third core-pulling component of this utility model.

[0038] Figure 12 This is a schematic diagram of the limiting component structure of this utility model.

[0039] Figure 13 This is a partial structural diagram of the limiting component of this utility model.

[0040] Figure 14 This is a partial structural diagram of the limiting component of this utility model.

[0041] Figure 15 This is a partial structural diagram of the limiting component of this utility model.

[0042] Figure 16 This is a partial structural schematic diagram of the present invention.

[0043] Figure 17 This is a schematic diagram of the first core-pulling component of this utility model.

[0044] Figure 18 This is a partial structural diagram of the first core-pulling component of this utility model.

[0045] Figure 19 This is a schematic diagram of the movable insert structure of this utility model. Detailed Implementation

[0046] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to specific embodiments and accompanying drawings. It should be understood that these descriptions are merely exemplary and not intended to limit the scope of this utility model. Furthermore, descriptions of well-known structures and technologies are omitted in the following description to avoid unnecessarily obscuring the concept of this utility model.

[0047] This utility model provides a multi-step parting and core-pulling mold, such as Figures 1-19As shown, the assembly includes, from top to bottom, a top plate 10, a flow channel plate 20, an upper mold 30, a lower mold 40, a pad plate 50, and a bottom plate 70. A pair of support plates 60, located on the left and right sides respectively, are provided between the pad plate 50 and the bottom plate 70 to support both. The area between the support plates 60 forms a top-loading space. Within this space, a fixed plate 80 and an ejector plate 90 are movably arranged vertically. The top plate 10 is fixedly connected to the flow channel plate 20, and the fixed plate 80 is fixedly connected to the ejector plate 90. The bottom plate 70 has multiple ejector rods that fall into the area of ​​the ejector plate 90. The injection molding machine can drive the ejector plate 90 to move towards the pad plate 50 through the ejector pin through the ejector pin hole (not shown in the figure). The upper mold 30 is provided with an upper mold core 31, the lower mold 40 is provided with a lower mold core 41, the lower mold core 41 is provided with a punch insert 42, the punch insert 42 is provided with a first core-pulling assembly 100, the punch insert 42 is provided with a second core-pulling assembly 200 on the left and right sides respectively, the punch insert 42 is provided with a third core-pulling assembly 300 on the front and rear sides respectively, and the lower mold 40 is provided with a limiting assembly 400 on both sides to limit the movement distance of the lower mold 40.

[0048] The flow channel plate 20 is provided with an upper pull rod 21 that is downward and can pull the upper mold 30. The lower end of the upper pull rod 21 is provided with an upper pull rod head 22. The upper mold 30 is provided with an upper pull rod hole 32 that allows the upper pull rod 21 to move and limits the movement stroke of the upper pull rod head 22.

[0049] During mold parting, the top plate 10 and the runner plate 20 separate first. The runner plate 20 drives the upper pull rod 21 to move. When the top plate 10 and the runner plate 20 have traveled a predetermined distance, the upper pull rod head 22 touches the limiting position in the upper pull rod hole 32, and the upper pull rod 21 drives the upper mold 30 to separate. The limiting position in the upper pull rod hole 32 can be implemented using any existing technology, such as by creating a stepped surface with a diameter smaller than that of the upper pull rod head 22.

[0050] The limiting component 400 includes a push block 401 disposed on one side of the lower mold 40 and a push strip 402 disposed on one side of the ejector plate 90 or the fixing plate 80 and extending towards the push block 401. The pad 50 is provided with a limiting block 403 to limit the stroke of the push block 401. Specifically, the limiting component 403 is provided with a limiting guide groove 404 to accommodate the push strip 402 and guide the push strip 402 vertically upward. The lower mold 40 is provided with mounting grooves 43 on both sides. The push block 401 is movably disposed in the mounting groove 43. A limiting return spring 405 is provided in the mounting groove 43 to support the push block 401. The limiting return spring 405 drives the push block 401 to partially extend out of the mounting groove 43. The limiting block 403 is provided with a limiting groove 406 to limit the upward movement stroke of the push block 401. The push block 401 extends out of the mounting groove 43 and falls into the limiting groove 406. This portion moves within the limiting groove 406 as the lower die 40 moves. When the lower die 40 reaches its end point, it cannot move further, thus limiting the travel distance of the lower die 40. The outer end of the push block 401 is provided with a contraction slope 407 that slopes downwards and outwards. The limiting groove 406 is provided with a contraction guide surface 408 corresponding to the contraction slope 407. The fixing plate 80 is provided with multiple movable ejector pins 81 whose ends can pass through the punch insert 42.

[0051] During mold parting, after the upper mold 30 separates, the injection molding machine drives the ejector plate 90 to move through the ejector pin hole. At this time, the pusher 402, fixed to one side of the ejector plate 90 or the fixed plate 80, moves with the ejector plate 90. The pusher 402 pushes the pusher block 401 to drive the lower mold 40 to move. During this stage, because the lower mold 40 and the ejector plate 90 move synchronously, the movable ejector pin 81 will not extend out of the punch insert 42 to eject the product. When the pusher block 401 reaches its end point, the lower mold 40 stops moving, and the ejector plate 90 continues to move. During this stage... As the pusher bar 402 continues to push the pusher block 401, the shrinking inclined surface 407 of the pusher block 401 is driven to fit against the shrinking guide surface 408 of the limiting groove 406. The pusher block 401 is guided by the shrinking guide surface 408 to shrink into the mounting groove 43. The limiting reset spring 405 is deformed by pressure, while the pusher bar 402 continues to move forward along the limiting guide groove 404. Since the lower mold 40 no longer moves, the distance between the ejector plate 90 and the lower mold 40 is shortened, and the movable ejector pin 81 passes through the punch insert 42 to eject the product.

[0052] The first core-pulling assembly 100 includes a movable insert 101 provided at the undercut position of the injection molded product corresponding to the punch insert 42. The number of the first core-pulling assemblies 100 is equal to the number of movable inserts 101 required for the corresponding injection molded product to pull the core at the undercut position. The pad 50 is provided with an insert block 102 that extends into the punch insert 42. The insert block 102 is provided with a first inclined surface 103 that slopes outward and downward. The movable insert 101 is movably connected along the first inclined surface 103. The first core-pulling assembly 100 is provided with a first slide rail 104 that has the same inclination as the first inclined surface 103. The movable insert 101 is provided with a first slide groove 105 that matches the first slide rail 104. The movable insert 101 can move along the first slide rail 104. The insert block 102 is provided with a first guide block 106 that is perpendicular to the first inclined surface 103 on both sides. The punch insert 42 is provided with a first guide groove 107 that corresponds to the first guide block 106 and is perpendicular to the first inclined surface 103. The movable insert 101 can move along the first guide groove 107.

[0053] During the stage from the start of the movement of the lower mold 40 to the end of its stroke, as the lower mold 40 separates, the distance between the insert block 102 and the lower mold 40 gradually increases. The lower mold 40 drives the movable insert 101 to move. At this time, the movable insert 101 moves towards the inside of the punch insert 42 under the guidance of the first slide rail 104, away from the injection molded product. The first guide groove 107 is set to further guide the movable insert 101 as it moves inward, and at the same time support the movable insert 101 to ensure the stability of the movement of the movable insert 101.

[0054] The second core-pulling assembly 200 includes a horizontal slider 201 disposed on either the left or right side of the punch insert 42 and slidable left and right, and a horizontal core-pulling component 202 fixedly connected to the horizontal slider 201. The horizontal slider 201 is provided with a second inclined surface 203 that slopes outward and downward. The upper mold 30 is provided with a second guide surface 33 corresponding to the second inclined surface 203. The upper mold 30 is provided with a slider guide rod 34 with the same slope and direction as the second inclined surface 203. The horizontal slider 201 is provided with a guide through hole 204 corresponding to the slider guide rod 34. The two sides of the horizontal slider 201 are respectively provided with a second slide rail 205 with the same sliding direction. The lower mold 40 is provided with a second slide groove 44 that matches the second slide rail 205. The lower mold 40 and the second inclined surface 203 corresponding to the bottom of the horizontal slider 201 are respectively provided with a plurality of wear-resistant plates 206. The bottom of the horizontal slider 201 is provided with a horizontal positioning groove 207. The lower mold 40 is provided with a horizontal positioning block 45 that matches the horizontal positioning groove 207. The horizontal positioning block 45 and the lower mold 10 are elastically connected in a retractable manner.

[0055] In one embodiment, during the separation stage of the upper mold 30, the slider guide rod 34 moves with the upper mold 30 and is withdrawn from the guide through hole 204. The slider guide rod 34 drives the transverse slider 201 to move outward. At this time, the matching of the second slide rail 205 and the second slide groove 44 guides and restricts the movement of the transverse slider 201, ensuring the stability of the movement of the transverse slider 201. During mold closing, the slider guide rod 34 drives the transverse slider 201 to move inward. During this stage, the transverse positioning block 45 is in a compressed state. When it reaches the mold closing end point, the transverse positioning block 45 aligns with the transverse positioning groove 207, and the transverse positioning block 45 springs up and embeds into the transverse positioning groove 207 to assist in mold closing positioning and ensure mold closing accuracy. The elastic extension and retraction of the transverse positioning block 45 can be achieved by any existing technology, such as opening a hole in the lower mold 40 and placing a spring inside to support the transverse positioning block 45, so that the transverse positioning block 45 can extend or retract into the hole.

[0056] The third core-pulling assembly 300 includes a longitudinal slider 301 disposed on either the front or rear side of the punch insert 42 and capable of sliding back and forth or obliquely. The longitudinal slider 301 has a longitudinal core-pulling part 302 at one end near the punch insert 42. The longitudinal slider 301 is provided with an oblique sliding groove 303 that slopes outward and downward. The upper die 30 is provided with an oblique guide block 35 corresponding to the oblique sliding groove 303. The longitudinal slider 301 is provided with a third slide rail 304 on both sides, which is consistent with its sliding direction. The lower die 30 is provided with a third sliding groove (not shown in the figure) that matches the third slide rail 304. The longitudinal slider 301 is provided with a mounting hole 305 on the side near the punch insert 42. A core-pulling return spring 306 for supporting the longitudinal slider 301 and the punch insert 42 is provided in the mounting hole 305. The bottom of the longitudinal slider 301 is provided with a longitudinal positioning groove 307. The lower die 40 is provided with a longitudinal positioning block 46 that matches the longitudinal positioning groove 307. The longitudinal positioning block 46 and the lower die 40 are elastically connected in a telescopic manner.

[0057] In one embodiment, during the separation stage of the upper mold 30, the inclined guide block 35 is withdrawn from the inclined slide groove 303, and the inclined guide block 35 drives the longitudinal slider 301 to move outward. At this time, the matching of the third slide rail 304 and the third slide groove guides and restricts the movement of the longitudinal slider 301, ensuring the stability of the movement of the longitudinal slider 301. During mold closing, the inclined guide block 35 drives the longitudinal slider 301 to move inward. During this stage, the longitudinal positioning block 46 is in a compressed state. When it reaches the mold closing end point, the longitudinal positioning block 46 aligns with the longitudinal positioning groove 307, and the longitudinal positioning block 46 springs up and embeds into the longitudinal positioning groove 307 to assist in mold closing positioning and ensure mold closing accuracy. The elastic extension and retraction of the longitudinal positioning block 46 can be achieved by any existing technology, such as opening a hole in the lower mold 40 and placing a spring inside to support the longitudinal positioning block 46, so that the longitudinal positioning block 46 can extend or retract into the hole.

[0058] The pad 50 is provided with an upward pull rod 51, and the upper end of the pull rod 51 is provided with a pull rod head 52. The lower mold 40 is provided with a pull rod hole 47 that allows the pull rod 51 to move and limits the travel of the pull rod head 52. The travel of the pull rod head 52 in the pull rod hole 47 is equal to the travel distance of the push block 401 in the limiting groove 406. During the separation process of the lower mold 40, the pull rod head 52 moves in the pull rod hole 47. After the lower mold 40 travels to a predetermined distance, the pull rod head 52 touches the limiting position in the pull rod hole 47, and the lower mold 40 can no longer move to separate. This setting forcibly limits the travel distance of the lower mold 40, ensuring that the push block 401 can retract into the mounting groove 43 under the guidance of the shrinkage guide surface 408 and the push of the push bar 402 after the end of its travel, avoiding interference, and also ensuring that the movable ejector pin 81 can continue to move to eject the injection molded product.

[0059] A buffer spring 82 is provided on the fixed plate 80, passing through the pad 50 and forming a support between the fixed plate 80 and the lower mold 40. Multiple anti-collision pads (not shown in the figure) are provided at the bottom of the ejector plate 90. The buffer spring 82 buffers the components associated with the movement of the ejector plate 90 and drives the ejector plate 90 to reset. The anti-collision pads prevent the ejector plate 90 from directly impacting the base plate 70 when resetting, mitigating the impact force and preventing the movable ejector pin 81 from being affected by excessive vibration over a long period, thus maintaining its positional accuracy.

[0060] Working principle:

[0061] The mold-making stage is completed in the following steps:

[0062] In the first step, the top plate 10 and the runner plate 20 are separated. At this time, the sprue material is carried away by the runner plate 20 and the sprue material is automatically removed from the injection molded product. The specific implementation can be achieved by any existing technology, such as setting a hook in the runner plate 20 to extend into the runner of the sprue material. After the sprue material is solidified, it can be pulled away by the hook.

[0063] In the second step, the runner plate 20 drives the upper pull rod 21 to move. When the upper pull rod head 22 reaches the corresponding limiting position of the upper pull rod hole 32, the upper pull rod 21 drives the upper mold 30 to separate. During the process of the upper mold 30 separating, the horizontal slider 201 of the second core pulling assembly 200 and the vertical slider 301 of the third core pulling assembly 300 move outward to pull the core. The upper mold 30 gradually travels to the end point. In this stage, the second core pulling assembly 200 and the third core pulling assembly 300 complete the core pulling work on the outside of the injection molded product.

[0064] In the third step, after the upper mold 30 completes its stroke, the injection molding machine drives the ejector plate 90 to move towards the pad plate 50. The pusher 402 drives the lower mold 40 to separate through the pusher block 401. The pusher block 401 travels along the limiting groove 406 to the end point. At this time, the pull rod head 52 also moves to the limiting position of the pull rod hole 47. The lower mold 40 no longer moves. In this stage, the sliding insert 101 of the first core-pulling assembly 100 retracts inward with the first slide rail 104 and the first guide groove 107 as guides. The injection molded product completes the internal core-pulling work.

[0065] Third, after the lower mold 40 stops moving, the ejector plate 90 continues to move. Under the push of the ejector bar 402 and the guidance of the shrinkage guide surface 408 and the shrinkage slope 407, the ejector block 401 retracts into the mounting groove 43. The ejector bar 402 continues to move without obstruction. At this time, the movable ejector pin 81 continues to move with the ejector plate 90 to complete the ejection of the core-pulling injection molded product.

[0066] Mold closing stage:

[0067] 1. The ejector plate 90 is reset under the elastic recovery action of the buffer spring 82. The push bar 402 moves with the ejector plate 90 and no longer presses the push block 401. The push block 401 returns to the pop-out position under the action of the limit reset spring 405, and its end falls into the limit groove 406. The movable ejector 81 is reset.

[0068] 2. The ejector plate 90 continues to reset, and the pull rod 51 drives the lower mold 40 to reset. During this stage, the movable insert 101 is reset under the traction of the first slide rail 104 and the guidance of the first guide groove 107.

[0069] 3. The injection molding machine drives the top plate 10 and the runner plate 20 to reset;

[0070] 4. Further, the injection molding machine drives the upper mold 30 to reset. At this stage, the transverse slider 201 of the second core-pulling assembly 200 is reset under the traction of the slider guide rod 34, and the longitudinal slider 301 of the third core-pulling assembly 300 is reset under the traction of the inclined guide block 35, thus completing the overall mold closing.

[0071] It should be understood that the specific embodiments described above are merely illustrative or explanatory of the principles of this utility model and do not constitute a limitation thereof. Therefore, any modifications, equivalent substitutions, improvements, etc., made without departing from the spirit and scope of this utility model should be included within its protection scope. Furthermore, the appended claims are intended to cover all variations and modifications falling within the scope and boundaries of the appended claims, or equivalent forms of such scope and boundaries.

Claims

1. A multi-step parting and core-pulling mold, characterized in that, The assembly includes, from top to bottom, a top plate, a runner plate, an upper mold, a lower mold, a backing plate, and a bottom plate. A pair of support plates, separate on the left and right sides and supporting both, are positioned between the backing plate and the bottom plate. The area between the support plates forms an ejector space. Within this ejector space, a fixed plate and an ejector pin plate are movably arranged vertically. The upper mold has an upper mold core, and the lower mold has a lower mold core. The runner plate has a downward-pointing upper pull rod that can pull the upper mold. The lower end of the upper pull rod has an upper pull rod head. The upper mold has an upper pull rod hole that allows the upper pull rod to move but limits the travel of the upper pull rod head. The lower mold core is provided with a punch insert; the punch insert is provided with a first core-pulling assembly, the first core-pulling assembly includes a movable insert provided at the undercut position of the punch insert corresponding to the undercut position of the injection molded product, the backing plate is provided with an insert block extending into the punch insert, the insert block is provided with a first inclined surface that slopes outward and downward, and the movable insert is movably connected along the first inclined surface; the lower mold is provided with limiting components on both sides to restrict the movement distance of the lower mold, the limiting components include a push block provided on one side of the lower mold and a push strip provided on one side of the ejector plate or fixed plate and extending towards the push block, and a limiting block is provided on the backing plate to restrict the stroke of the push block.

2. The multi-step parting and core-pulling mold according to claim 1, characterized in that, The first core-pulling assembly has a first slide rail with the same slope on the first inclined surface, the movable insert has a first slide groove that matches the first slide rail, the insert block has a first guide block perpendicular to the first inclined surface on both sides, and the punch insert has a first guide groove that corresponds to the first guide block and is perpendicular to the first inclined surface.

3. The multi-step parting and core-pulling mold according to claim 1, characterized in that, The limiting component has a limiting guide groove in the limiting block to accommodate the push bar and guide the push bar vertically upward. The lower mold has mounting grooves on both sides. The push block is movably disposed in the mounting groove. The mounting groove is provided with a limiting return spring to support the push block. The limiting block has a limiting groove to restrict the upward movement of the push block.

4. A multi-step parting and core-pulling mold according to claim 3, characterized in that, The outer end of the push block is provided with a shrinking slope that slopes outward and downward, the limiting groove is provided with a shrinking guide surface corresponding to the shrinking slope, and the fixing plate is provided with multiple movable ejector pins whose ends can pass through the punch insert.

5. A multi-step parting and core-pulling mold according to claim 1, characterized in that, The punch insert is provided with second core-pulling assemblies on its left and right sides respectively. The second core-pulling assembly includes a horizontal slider that is disposed on either the left or right side of the punch insert and can slide left and right, and a horizontal core-pulling component fixedly connected to the horizontal slider. The horizontal slider is provided with a second inclined surface that slopes outward and downward. The upper die is provided with a second guide surface corresponding to the second inclined surface. The upper die is provided with a slider guide rod that has the same slope and direction as the second inclined surface. The horizontal slider is provided with a guide through hole corresponding to the slider guide rod. The two sides of the horizontal slider are respectively provided with second slide rails that have the same sliding direction as the slider. The lower die is provided with a second slide groove that matches the second slide rails.

6. A multi-step parting and core-pulling mold according to claim 5, characterized in that, The lower mold and the second inclined surface corresponding to the bottom of the horizontal slider are respectively provided with multiple wear-resistant plates. The bottom of the horizontal slider is provided with a horizontal positioning groove. The lower mold is provided with a horizontal positioning block that matches the horizontal positioning groove. The horizontal positioning block and the lower mold are elastically connected in a retractable manner.

7. A multi-step parting and core-pulling mold according to claim 1, characterized in that, The punch insert is provided with a third core-pulling assembly on both the front and rear sides. The third core-pulling assembly includes a longitudinal slider that is located on either the front or rear side of the punch insert and can slide back and forth or obliquely. The longitudinal slider has a longitudinal core-pulling part at the end near the punch insert. The longitudinal slider has an oblique sliding groove that slopes outward and downward. The upper die is provided with an oblique guide block corresponding to the oblique sliding groove. The longitudinal slider has a third slide rail on both sides that is consistent with its sliding direction. The lower die has a third sliding groove that matches the third slide rail.

8. A multi-step parting and core-pulling mold according to claim 7, characterized in that, The longitudinal slider has a mounting hole on the side near the punch insert. A core-pulling return spring is installed in the mounting hole to support the longitudinal slider and the punch insert. The bottom of the longitudinal slider has a longitudinal positioning groove. The lower die has a longitudinal positioning block that matches the longitudinal positioning groove. The longitudinal positioning block and the lower die are elastically connected in a telescopic manner.

9. A multi-step parting and core-pulling mold according to claim 4, characterized in that, The pad is provided with an upward pull rod, the upper end of the pull rod is provided with a pull rod head, and the lower mold is provided with a pull rod hole that allows the pull rod to move and limits the movement of the pull rod head.

10. A multi-step parting and core-pulling mold according to claim 1, characterized in that, The fixed plate is provided with a buffer spring that passes through the pad and forms a support between the fixed plate and the lower mold, and the bottom of the ejector plate is provided with multiple anti-collision pads.

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