Traceless product two-color mold, working method and traceless two-color plastic part

Abstract

The invention provides a traceless product double-color mold, a working method and a traceless double-color plastic part, and the traceless product double-color mold comprises a first mold which is arranged at a first station and comprises a first front mold core, a first rear mold core and a first inclined wedge; the second mold is arranged at the second station and comprises a second front mold core, a second rear mold core and a second inclined wedge; the public module can move between a first station and a second station and comprises a public rear mold and a public sliding block arranged on the outer side of the public rear mold in a sliding fit mode, and mold holes allowing the first rear mold core and the second rear mold core to be inserted therein are formed in the public rear mold; when the first mold is split, the first inclined wedge drives the public sliding block to be clamped, and a hard rubber product on the public rear mold is fixed; and when the first mold and the second mold are closed, the first wedge or the second wedge drives the common sliding block to loosen and realize avoidance. The traceless product double-color mold is compact in structure, small in size, high in production efficiency and good in product quality.

Description

Technical Field

[0001] This invention relates to molds, and particularly to a two-color mold for seamless products, a working method thereof, and a two-color plastic part for seamless products. Background Technology

[0002] Existing high-end, two-color medical syringe plungers are made of seamless two-color plastic parts, requiring the product to have no parting lines or ejector pin marks, achieving an extremely seamless appearance. This requirement is very difficult to meet with ordinary mold technology.

[0003] Currently available two-color molds all require that the product structure of the post-mold portion of the first and second injections be completely identical. This ensures that after the first injection, the post-mold can rotate to the second injection position without moving the product, thus completing the two-color molding.

[0004] If the product structure results in completely different mold sections for the first and second injections, traditional two-color mold technology cannot achieve this. The biggest obstacle lies in products with different mold sections. After the first injection, the product needs to leave space for the second injection, so the product cannot be completely fixed to the mold, making it impossible for traditional two-color molds to achieve products with different mold sections.

[0005] Given the above requirements, when the product needs to be seamless and have a completely different product structure between the first and second injection molds, the existing two-color mold technology is even less able to meet the product requirements.

[0006] While overmolding can achieve seamless two-color injection molding, it requires making a hard plastic part first and then manually placing it into a soft plastic mold, which is inefficient. Secondly, because of the removal and re-placement process, there are at most two injection points. Otherwise, due to product consistency and the movement error of the hard plastic part, the sealing part between the hard and soft plastic parts cannot be perfect, and the product will have flash defects. Therefore, overmolding is not a truly good solution. Summary of the Invention

[0007] The technical problem to be solved by the present invention is to provide a seamless product injection molded part with a compact structure, low manufacturing cost, reliable operation and high molding quality, a seamless product two-color mold and its working method.

[0008] The present application provides a kind of traceless double-color plastic parts, it includes hard glue structure and soft glue structure, the hard glue structure includes a rod body 41 and the circular press plate 43 of setting in the lower end of the rod body 41, the lower end surface of the press plate 43 is inwardly concave arc surface, the sidewall of the press plate 43 is inclined plane, and press plate 43 forms the inverted circular table structure of upper end big lower end small;The upper surface of the press plate 43 is provided with an annular groove, and the upper surface edge of the press plate 43 forms a ring-shaped protrusion 431, a plurality of through holes are penetrated between the annular groove and the arc surface;The soft glue structure includes the first soft glue layer 442 of setting on the arc surface, the second soft glue layer 441 of setting in the annular groove and the soft glue column 443 of setting in the through hole and connecting the first soft glue layer 442 and the second soft glue layer 441.

[0009] Meanwhile, the present application also provides a kind of traceless product double-color mould, it includes:

[0010] First mould, it is arranged in first station, is used for hard glue structure injection molding, including first front die 11, first back die 12 and first inclined wedge 14;

[0011] Second mould, it is arranged in second station, is used for soft glue structure injection molding, including second front die 21, second back die 22 and second inclined wedge 24;

[0012] Common module 3, as common end, can move between first station and second station, including common back die 32 and the common slider 31 of sliding fit in the outside of the common back die 32, the common back die 32 is opened on and is inserted with the die hole 320 of the first back die 12 and the second back die 22;

[0013] When the first mould is divided, the first inclined wedge 14 drives the common slider 31 clamping, and realizes the fixation of hard glue product on the common back die 32;

[0014] When the first mould and the second mould are closed, the first inclined wedge 14 or the second inclined wedge 24 drives the common slider 31 to loosen and realizes avoidance.

[0015] Further, the first inclined wedge 14 can move along the closing and dividing direction, and moves synchronously with the first front die 11 or first back die 12, and when the first mould is divided, the first inclined wedge 14 is separated from the common slider 31;The second inclined wedge 24 can move along the closing and dividing direction, and moves synchronously with the second front die 21 or second back die 22, and when the second mould is divided, the second inclined wedge 24 is separated from the common slider 31.

[0016] Further, the common slider 31 is provided with inclined guide holes corresponding to the first inclined wedge 14 and the second inclined wedge 24, and the first inclined wedge 14 and the second inclined wedge 24 are inserted into the inclined guide holes to drive the common slider 31 to slide and realize compression and release.

[0017] Further, the common slider 31 is provided with a first inclined guide hole 310 corresponding to the first inclined wedge 14 and a second inclined guide hole 311 corresponding to the second inclined wedge 24, and the first inclined guide hole 310 and the second inclined guide hole 311 are opposite in direction; the first inclined wedge 14 and the second inclined wedge 24 are arranged at the upper and lower ends of the common module respectively.

[0018] Further, the end surface of the back mold 32 is provided with a part of the forming surface of the hard rubber product and can support the hard rubber product after the first mold is opened.

[0019] Further, the part of the forming surface is used for the forming of the inclined side wall of the pressing plate.

[0020] Further, the end of the common slider 31 is provided with a pressing surface 312 facing the common back mold 32 and used for fitting the edge top surface of the hard rubber product.

[0021] Further, the side wall of the first mold and the second mold at the closing position is provided with a avoiding slot for avoiding the common slider 31.

[0022] Further, the closing direction of the first mold and the second mold is perpendicular to the horizontal plane, and the injection molding product after opening is in a vertical state.

[0023] Further, the first mold and the second mold are arranged in parallel, the common module 3 is connected with a rotating mechanism and can move between the first mold and the second mold, and the rotating axis of the common module 3 is parallel to the closing direction and the opening direction.

[0024] Further, the common module 3 is two groups and can move between the first mold and the second mold alternately.

[0025] Further, the upper end and / or the side wall of the back mold 32 is provided with a first limiting part, and the common slider 31 is provided with a second limiting part, and when the common slider 31 is in the pressing state, the second limiting part contacts the first part to realize limiting.

[0026] Further, the common slider 31 is provided with a sliding damping, or the contact surface between the common slider 31 and the common back mold 32 is a smooth surface and can be attracted when in contact.

[0027] Further, the common slider 31 is multiple and is distributed circumferentially.

[0028] Meanwhile, the application also provides a working method of the double-color mold without trace, which comprises the following steps.

[0029] S1, resetting, the common mold 3 moves to the first station and is located between the first front mold core 11 and the first rear mold core 12;

[0030] S2, primary mold closing, the first front mold core 11 and the first rear mold core 12 move towards each other to realize mold closing, after mold closing, the first rear mold core 12 is located in the mold hole 320 of the common rear mold 32, and the first rear mold core 12, the common rear mold 32 and the first front mold core 11 form a first forming cavity for hard glue structure forming;

[0031] During mold closing, the first inclined wedge 14 moves along the mold closing direction and is inserted into the inclined guide hole of the common slider 31, pushes the common slider 31 to move outward, realizes avoiding and provides space for mold closing of the first mold;

[0032] S3, primary injection, the first injection machine injects hard glue material into the first forming cavity to complete injection molding of the hard glue structure;

[0033] S4, primary cooling, the hard glue structure is cooled and shaped to ensure that the structure is stable and reaches the demolding strength;

[0034] S5, primary mold opening, the first front mold core 11 and the first rear mold core 12 move along the mold opening direction to realize mold opening, after mold opening, the first rear mold core 12 is located outside the mold hole 320 of the common rear mold 32, and the hard glue structure is left on the common rear mold 32;

[0035] During mold opening, the first inclined wedge 14 moves along the mold opening direction, drives the common slider 31 to move inward, and makes the pressing surface 312 at the end of the common slider 31 press the edge upper surface of the hard glue structure to realize fixing of the hard glue product;

[0036] After mold opening is completed, the first inclined wedge 14 and the common slider 31 are disengaged;

[0037] S6, shifting, the driving mechanism drives the common mold 3 with the hard glue product to move to the second station and is located between the second front mold core 21 and the second rear mold core 22;

[0038] S7, secondary mold closing, the second front mold core 21 and the second rear mold core 22 move towards each other to realize mold closing, after mold closing, the second rear mold core 22 extends into the mold hole 320 of the common rear mold 32, and the second rear mold core 22, the common rear mold 32 and the second front mold core 21 form a second forming cavity for soft glue structure forming;

[0039] During the clamping process, the second inclined wedge 24 moves along the clamping direction and is inserted into the inclined guide hole of the common slider 31, pushes the common slider 31 to move outward, releases the compression of the edge of the hard rubber product, and provides space for the clamping of the second mold;

[0040] S8, secondary injection, the second injection machine injects soft rubber material into the second forming cavity, so that the soft rubber material is wrapped on the surface of the hard rubber structure;

[0041] S9, secondary cooling, cooling and shaping the soft rubber product to ensure that the soft rubber and the hard rubber are fully combined and reach the demolding strength;

[0042] S14, secondary mold opening, the second front mold core 21 and the second rear mold core 22 move in the opposite direction of the mold opening, realize mold opening, and after mold opening, the second rear mold core 22 is located outside the mold hole 320 of the common rear mold 32, and the product of the soft rubber wrapped on the hard rubber is left on the common rear mold 32;

[0043] During the mold opening process, the second inclined wedge 24 moves along the mold opening direction and is disengaged from the common slider 31;

[0044] S11, blanking, the formed product is taken off from the common rear mold 32 by a mechanical hand or an air nozzle;

[0045] S12, resetting, the driving mechanism drives the common mold 3 to return to the first station.

[0046] Further, in step S5, the common slider 31 is attached to the common rear mold under the action of damping or smooth surface adsorption, so that displacement does not occur during the movement of the common mold 3.

[0047] The traceless product double-color mold of the application sets the common rear mold and the movable common slider in cooperation, realizes that the hard rubber is transferred to the second station for soft rubber wrapping forming after being formed in the first station, realizes zero displacement of the hard rubber, effectively guarantees the accurate alignment of the mold cavity in the two injection molding processes, and improves the product quality; when the common mold is transferred, the hard rubber product is fixed by the common slider, so that the product is not loosened due to vibration or displacement during the transfer process, the position of the hard rubber part is accurate and unchanged when entering the second station, and the product quality is improved; the whole process does not need manual taking and placing of the hard rubber part, the common mold is automatically displaced, the production cycle is short; the mold hole of the common rear mold can accommodate the insertion of the rear mold core of the first mold or the second mold with completely different forming surfaces, whether the rear mold is a skeleton forming surface or a wrapping forming surface, mold clamping injection can be realized, so that the double-color injection molding demand of various product structures is compatible, and the mold versatility is improved; the traceless product double-color mold of the application has compact structure, small size, high production efficiency and good product quality. BRIEF DESCRIPTION OF DRAWINGS

[0048] Figure 1 It is a structure diagram of a traceless double-color plastic part;

[0049] Figure 2 Structure diagram of the first mold of the present application;

[0050] Figure 3 Parting diagram of the first mold of the present application;

[0051] Figure 4 Structure diagram of the second mold of the present application; Figure 3 Enlarged view of A part;

[0052] Figure 5 Structure diagram of the second mold of the present application;

[0053] Figure 6 Clamping diagram of the second mold of the present application;

[0054] Figure 7 Structure diagram of the second mold of the present application; Figure 6 Enlarged view of B part;

[0055] Figure 8 Parting diagram of the second mold of the present application;

[0056] Figure 9 Parting diagram of the second mold of the present application;

[0057] Figure 10 Schematic diagram of the common mold located at the first station of the present application;

[0058] Figure 11 Working schematic diagram of the first mold of the present application.

[0059] In the figure: 11, first front mold core, 12, first back mold core, 14, first inclined wedge, 21, second front mold core, 22, second back mold core, 24, second inclined wedge, 3, common mold, 31, common sliding block, 32, common back mold, 310, first inclined guide hole, 311, second inclined guide hole, 312, pressing surface, 320, mold hole, 41, rod body, 43, pressing plate, 431, annular protrusion, 441, second soft rubber layer, 442, first soft rubber layer, 443, soft rubber column. DETAILED DESCRIPTION

[0060] The embodiments of the present application will be described in detail below with reference to the accompanying drawings.

[0061] Reference is made to Figure 1The present application provides a traceless double-color plastic part, in particular, a push rod of a medical syringe, comprising a hard glue structure and a soft glue structure, wherein the hard glue structure comprises a rod body 41 and a circular pressing plate 43 arranged at the lower end of the rod body 41, the lower end surface of the pressing plate 43 is an inwardly concave arc surface, the side wall of the pressing plate 43 is a slope, and thus the pressing plate 43 forms an inverted circular table structure with a large upper end and a small lower end; the upper surface of the pressing plate 43 is provided with an annular groove, which forms an annular protrusion 431 at the edge of the upper surface of the pressing plate 43, and a plurality of through holes are arranged between the annular groove and the arc surface, in the embodiment, the through holes are a plurality of through holes and are uniformly distributed in the circumferential direction; the soft glue structure comprises a first soft glue layer 442, a second soft glue layer 441 and a soft glue column 443, wherein the first soft glue layer 442 is arranged on the surface of the arc surface, the second soft glue layer 441 is arranged in the annular groove and extends to the upper surface of the annular protrusion 431 at the edge, and the soft glue column is arranged in the through hole and is used for connecting the first soft glue layer 442 and the second soft glue layer 441.

[0062] The traceless double-color plastic part covers the first soft glue layer on the arc concave surface at the lower end of the pressing plate, conforms to the ergonomic design, the contact between the fingers and the soft glue layer is more fitted and soft when the medical staff pushes the syringe, and the fatigue caused by long-time operation is reduced; the annular groove is arranged on the upper surface of the pressing plate, the second soft glue layer is arranged in the annular groove, and the soft glue column is arranged between the first soft glue layer and the second soft glue layer to connect them, thereby forming a soft glue structure that penetrates from top to bottom, and the bonding strength between the soft glue and the hard glue is greatly improved, and the soft glue layer is effectively prevented from falling off or tearing during use; meanwhile, the slope structure is arranged on the side wall of the pressing plate, so that the pressing plate as a whole has an inverted circular table shape with a large upper end and a small lower end, which facilitates the support and transfer of the common module during injection molding, and thus double-color (glue) injection molding is realized.

[0063] Meanwhile, the present application also provides a traceless product double-color mold, which comprises a first mold, a second mold and a common module 3, as shown in Figures 2-11 .

[0064] The first mold is arranged at a first station and is used for injection molding of the hard glue structure, the first mold comprises a first front mold core 11, a first rear mold core 12 and a first inclined wedge 14, and the first rear mold core 12 and the first front mold core 11 can move to realize mold opening and mold splitting.

[0065] The second mold is arranged at a second station and is used for injection molding of the soft glue structure, the second mold comprises a second front mold core 21, a second rear mold core 22 and a second inclined wedge 24, and the second rear mold core 22 and the second front mold core 21 can move to realize mold opening and mold splitting.

[0066] The common module 3 as a common end can move between the first station and the second station, comprising a common back die 32 and common sliders 31 fitted outside the common back die 32, the common sliders 31 are multiple and uniformly distributed in the circumference, in the embodiment, the sliding direction of the common sliders 31 is perpendicular to the closing or opening direction, a die hole 320 is formed on the common back die 32, the die hole 320 can accommodate the first back die core 12 and the second back die core 22 to be inserted, after being inserted, a complete forming surface is formed.

[0067] When the first mold is opened, the first wedge 14 drives the common sliders 31 to be clamped, so as to fix the hard rubber product on the common back die 32, avoiding the hard rubber product on the common sliders from being loosened in the moving process, and affecting the quality of the soft rubber forming at the back end.

[0068] When the first mold and the second mold are closed, the first wedge 14 or the second wedge 24 drives the common sliders 31 to be loosened and to avoid;

[0069] When the first mold and the second mold are completely opened, the first wedge 14 or the second wedge 24 is separated from the common sliders 31, at this time, the common module 3 is not connected with the first mold or the second mold, and can move between the first station and the second station to perform soft rubber or hard rubber injection molding.

[0070] The common back die is provided, and the common back die is matched with the movable common sliders to realize that the hard rubber is transferred to the second station to perform soft rubber over-molding after being formed at the first station, the hard rubber is shifted with zero offset, the accurate alignment of the mold cavity in the twice injection molding process is effectively ensured, and the product quality is improved.

[0071] The die hole 320 of the common back die 32 can accommodate the back die core of the first mold or the second mold with completely different forming surfaces to be inserted, whether the back die is a skeleton forming surface or an over-molding surface, the mold can be closed and injection molded, so that the double-color injection molding demand of various product structures is compatible, and the mold versatility is improved.

[0072] The sliders are automatically loosened when the mold is closed, the avoidance is realized, the smooth injection is ensured, the movement stroke of the sliders is reduced, and the response speed and the overall volume of the common module are improved.

[0073] When the mold is opened, the wedge is separated from the common sliders, the common module is separated from the first mold or the second mold without connection, and then the common module can be freely switched between the first station and the second station to complete different injection molding processes.

[0074] When the common module is transferred, the hard rubber product is fixed by the common sliders, the product is prevented from being loosened due to vibration or displacement in the transfer process, the position of the hard rubber part is ensured to be accurate and unchanged when entering the second station, the product quality is improved, the hard rubber parts do not need to be manually taken and placed in the whole process, the common module is automatically shifted, and the production cycle is short.

[0075] The present application realizes the whole transfer of the hard glue forming to the second station for soft glue covering through the cooperation of the common rear mold and the common slider, ensures the accurate alignment of the mold cavity between the two injection molding, effectively improves the product consistency and yield, and at the same time, the structure is compatible with the mold switching of different forming surfaces, meets the production needs of multiple types of two-color products, significantly enhances the mold versatility and production line flexibility, and has compact structure, small size and high flexibility.

[0076] In the present application, the first inclined wedge 14 can move in the direction of mold closing and mold opening, and it can move synchronously with the first front mold core 11 or the first rear mold core 12, and when the first mold is opened, the first inclined wedge 14 is separated from the common slider 31; the second inclined wedge 24 can move in the direction of mold closing and mold opening, and it can move synchronously with the second front mold core 21 or the second rear mold core 22, and when the second mold is opened, the second inclined wedge 24 is separated from the common slider 31.

[0077] The inclined wedge moves synchronously with the first and second front mold cores or rear mold cores, directly uses the rigid power of mold closing and mold opening to drive the slider to move, the inclined wedge inserts into the slider inclined guide hole to push away when the mold is closed, and the inclined wedge drives the slider to clamp when the mold is opened, without additional power device and control system, the mold structure is more compact, the overall volume and manufacturing cost are reduced, and the action reliability and response speed are improved; after the first and second molds are completely opened, the inclined wedge moves synchronously with the mold core and is separated from the inclined guide hole of the slider, the common module is not connected with the mold of the previous station, so that the common module can be freely moved to another station by rotary or linear drive, and the mold hole 320 can accommodate the front and rear mold cores with completely different structures, which breaks through the core limitation that the rear mold structure of the traditional two-color mold must be consistent.

[0078] In the present embodiment, inclined guide holes corresponding to the first inclined wedge 14 and the second inclined wedge 24 are formed on the common slider 31, and the first inclined wedge 14 and the second inclined wedge 24 can drive the common slider 31 to slide after being inserted into the inclined guide holes, thereby realizing the pressing and releasing; in the present embodiment, a first inclined guide hole 310 corresponding to the first inclined wedge 14 and a second inclined guide hole 311 corresponding to the second inclined wedge 24 are formed on the common slider 31, the first inclined guide hole 310 and the second inclined guide hole 311 are inclined holes, and the inclined directions are opposite; and the first inclined wedge 14 and the second inclined wedge 24 are arranged at the upper and lower ends of the common module respectively.

[0079] The slider driving mechanism of the traditional two-color mold needs to occupy the space of the side or end surface of the mold, which leads to the increase of the volume of the mold, and cannot adapt to the miniaturization of two-color products, while the present application utilizes the mold space vertically through the design of reverse inclined guide holes and upper and lower inclined wedges, without occupying the side space, which expands the application scenarios of the mold.

[0080] In the present application, the end face of the common back mold 32 is provided with a part of the forming surface for forming the hard rubber product, that is, when the first mold is closed, the part of the forming surface of the common back mold 32 is spliced with the first back mold to form the lower forming surface. In the present embodiment, the part of the forming surface is used to press the inclined side wall of the pressing plate, which has a radial width and an axial depth. At the same time, the part of the forming surface is used to support the hard rubber product after the first mold is opened. The end face of the common back mold 32 serves as the main supporting surface of the hard rubber product. After the mold is opened, the hard rubber product is on the end face, and the pressing is realized to move integrally, which is stable in support. Manual or additional mechanism is not needed for transfer, which reduces the labor intensity of workers and improves the degree of automation. At the same time, the product positioning deviation caused by secondary placement is avoided, the accurate covering of hard rubber and soft rubber is ensured, and the product quality is improved.

[0081] The end of the common slider 31 is provided with a pressing surface 312 facing the common back mold 32, which is used to fit the edge top surface of the hard rubber product, specifically, the top surface of the annular protrusion of the pressing plate edge. Through axial fitting contact, the pressing is fixed, which can make the bottom surface of the hard rubber structure always in contact with the common back mold 32, improving the positional accuracy after transfer. The top surface of the annular protrusion is a non-appearance area. In the later soft rubber injection molding, the top surface of the annular protrusion also serves as a covering surface. The pressing surface 312 only contacts this area, completely avoiding the appearance sensitive area, and realizing markless pressing. Axial pressing not only avoids the appearance surface, but also avoids the deformation, damage or positional deviation of the hard structure caused by radial pressing, ensuring the structural integrity and positioning accuracy of the hard rubber part during the transfer process, and effectively improving the stability and product yield of two-color injection molding.

[0082] In order to realize the quick response of the common slider during mold opening and closing, and reduce the sliding, even if the common slider is close to the forming cavity, in the present embodiment, the side wall of the closing position of the first mold and the second mold is provided with a avoiding groove for avoiding the common slider 31.

[0083] In the present application, the closing direction of the first mold and the second mold is perpendicular to the horizontal plane, which makes the injection molded product after mold opening in a vertical state, that is, the rod body of the hard rubber product is vertical, and the pressing plate is located directly below the rod body. It not only can eliminate the horizontal placement of the parting line, ensure the parting line free of the main part, and improve the appearance beauty of the product; at the same time, it is convenient for pressing and fixing and position transfer.

[0084] The first mold and the second mold are arranged in parallel, the common mold 3 is connected with a rotating mechanism, the common mold 3 can move between the first mold and the second mold, and the rotating axis of the common mold 3 is parallel to the closing direction and the opening direction; in order to improve the production efficiency, the common mold 3 is two groups in the embodiment, and can move between the first mold and the second mold alternately; the common mold 3 is driven by the rotating mechanism to realize 180-degree accurate rotation, the switching between two stations is completed, and the hard glue injection molding process and the soft glue injection molding process are continuously and efficiently carried out; the common mold is accurately positioned and stably runs in the rotating process, the mold is high-speed responded, the forming cycle is obviously shortened, and the production efficiency is high.

[0085] In order to improve the movement accuracy of the common mold, the first limiting part is arranged on the upper end and / or the side wall of the common back mold 32, and the second limiting part is arranged on the common slider 31; when the common slider 31 is in the pressing state, the second limiting part is in contact with the first part, so that the limiting is realized, the movement stroke of the common slider is ensured, the positioning deviation caused by the movement overshoot is avoided, the slider is accurately attached to the edge of the hard glue product when the mold is closed, and the stable pressing is realized; in order to prevent the common mold from deviating due to inertia or external force interference in the movement process, the sliding damping is arranged on the common slider 31, or the contact surface of the common slider 31 and the common back mold 32 is a smooth surface, and the smooth surface can be attracted when being attached; the sliding damping can absorb the impact energy when the wedge is driven, the shaking or impact is avoided when the slider is contacted, the rebound trend of the slider is offset, the displacement of the slider after pressing is ensured, and the pressing stability is improved. By arranging the smooth surface, the adsorption force can be formed when the two smooth surfaces are attached, the slider is loosened or deviated due to vibration or inertia in the transfer process is avoided, the stability of the pressing is ensured, the adsorption force can be overcome and the common slider can be driven when the wedge is inserted into the inclined hole of the common slider, and the structure is simple and compact, and no additional parts are needed.

[0086] Meanwhile, the application also provides a working method of the traceless product double-color mold, which comprises the following steps:

[0087] S1, resetting, the common mold 3 moves to the first station and is located between the first front mold core 11 and the first back mold core 12;

[0088] S2, one-time mold closing, the first front mold core 11 and the first back mold core 12 move towards each other to realize mold closing, after mold closing, the first back mold core 12 is located in the mold hole 320 of the common back mold 32, and a first forming cavity for hard glue structure forming is formed between the first back mold core 12, the common back mold 32 and the first front mold core 11;

[0089] During the mold closing process, the first wedge 14 moves along the mold closing direction and is inserted into the inclined guide hole of the common slider 31, pushes the common slider 31 to move outward, realizes the avoidance and provides space for the mold closing of the first mold;

[0090] S3, one injection, the first injection machine injects the first forming cavity with hard glue material, and the injection molding of the hard glue structure is completed;

[0091] S4, one cooling, the hard glue structure is cooled and shaped to ensure its stable structure and demolding strength;

[0092] S5, one mold opening, the first front mold core 11 and the first back mold core 12 move along the mold opening direction to realize mold opening. After mold opening, the first back mold core 12 is located outside the mold hole 320 of the common back mold 32, and the hard glue structure is left on the common back mold 32. Specifically, the inclined side wall of the pressing plate of the hard glue structure is in contact with the forming surface on the common mold to realize support;

[0093] During mold opening, the first inclined wedge 14 moves along the mold opening direction, drives the common slider 31 to move inward, and makes the pressing surface 312 at the end of the common slider 31 press the upper surface of the annular protrusion at the edge of the pressing plate, thereby fixing the hard glue product;

[0094] After mold opening is completed, the first inclined wedge 14 is disengaged from the common slider 31, so that the common mold and the first mold are disengaged from each other and do not interfere with each other, thereby ensuring smooth transfer of the position of the common mold;

[0095] The common slider 31 is attached to the common back mold under the action of damping or smooth surface adsorption, so as to ensure that the common mold does not displace during movement;

[0096] S6, displacement, the driving mechanism drives the common mold 3 with the hard glue product to move to the second station. In this embodiment, the driving structure is a rotating driving structure, so that the common mold is located between the second front mold core 21 and the second back mold core 22;

[0097] S7, second mold closing, the second front mold core 21 and the second back mold core 22 move towards each other to realize mold closing. After mold closing, the second back mold core 22 extends into the mold hole 320 of the common back mold 32, and the second back mold core 22, the common back mold 32 and the second front mold core 21 form a second forming cavity for forming a soft glue structure;

[0098] During mold closing, the second inclined wedge 24 moves along the mold closing direction and is inserted into the inclined guide hole of the common slider 31, drives the common slider 31 to move outward, releases the pressing of the edge of the hard glue product, and provides space for mold closing of the second mold;

[0099] S8, second injection, the second injection machine injects the soft glue material into the second forming cavity, so that the soft glue material covers the surface of the hard glue structure, specifically, covers the surface of the pressing plate, the through hole on the pressing plate is used to connect the soft glue layers on the upper and lower surfaces on one hand, and on the other hand, can contain the soft glue to flow from one end to the other end. In the embodiment, the soft glue flows from the lower end to the upper end.

[0100] S9, secondary cooling, the soft glue product is cooled and shaped to ensure that the soft glue and the hard glue are fully combined and reach the demolding strength;

[0101] S10, secondary mold opening, the second front mold core 21 and the second rear mold core 22 move in the parting direction to realize parting, and after parting, the second rear mold core 22 is located outside the mold hole 320 of the common rear mold 32, and the product with the soft glue covering the hard glue is left on the common rear mold 32 as a whole.

[0102] During the parting process, the second inclined wedge 24 moves in the parting direction and is disengaged from the common slider 31, so that the common module is disengaged from the second mold and does not interfere with each other, thereby ensuring the smooth transfer of the position of the common module;

[0103] S11, blanking, the formed product is taken off from the common rear mold 32 by the mechanical hand or the air nozzle;

[0104] S12, reset, the driving mechanism drives the common module 3 to return to the first station and reciprocates in turn.

[0105] The application discards the traditional mold design method, changes the product from the traditional horizontal placement to the vertical placement, and places all the glue positions of the main part in the front mold, so that the parting line of the horizontal placement is avoided, and the parting line mark of the main part is ensured. The product is finally ejected by blowing instead of the traditional ejector pin, so that the ejector pin mark of the product is avoided.

[0106] After the hard glue product of the first mold is formed, the mold is designed as a yielding structure to ensure that different rear molds are double-colored during the soft glue forming of the second mold. However, because of the yielding structure, the product cannot be fixed, and a glue-free slider structure is designed in the mold. After the first mold is formed and opened, the glue-free slider is pressed against the product under the action of the inclined wedge to fix the product. After rotating 180 degrees to the second mold, the glue-free slider is disengaged from the product under the action of the second mold inclined wedge to realize the soft glue injection of the second mold.

[0107] Because there is no glue position on the slider throughout the process, the slider only functions to fix the product, so the slider will not appear parting lines on the product, and the no-mark requirement of the product is realized.

[0108] The above merely describes the preferred embodiments of the present application, and it should be pointed out that, for those skilled in the art, several improvements and refinements can be made without departing from the technical principles of the present application, and these improvements and refinements should also be considered as the protection scope of the present application.

Claims

1. A seamless two-color plastic part, characterized in that: The device includes a hard rubber structure and a soft rubber structure. The hard rubber structure includes a rod and a circular pressing plate disposed at the lower end of the rod. The lower end surface of the pressing plate is an inwardly concave arc surface, and the side wall of the pressing plate is inclined, forming an inverted frustum structure with a larger upper end and a smaller lower end. The upper surface of the pressing plate is provided with an annular groove, and the edge of the upper surface of the pressing plate forms an annular protrusion. Multiple through holes penetrate between the annular groove and the arc surface. The soft rubber structure includes a first soft rubber layer disposed on the arc surface, a second soft rubber layer disposed in the annular groove, and a soft rubber column disposed in the through holes and connecting the first soft rubber layer and the second soft rubber layer.

2. A seamless product dual-color mold, characterized in that, include: The first mold, set at the first station, is used for injection molding of hard plastic structures, and includes a first front mold core, a first rear mold core, and a first wedge. The second mold, set at the second station, is used for injection molding of soft rubber structures, including a second front mold core, a second rear mold core, and a second wedge. The common module, as a common end, can move between the first station and the second station, including a common rear mold and a common slider that slides on the outside of the common rear mold. The common rear mold has a mold hole for inserting the first rear mold core and the second rear mold core. When the first mold is being separated, the first wedge drives the common slider to clamp and fix the hard plastic product on the common rear mold; When the first mold and the second mold are closed, the first wedge or the second wedge drives the common slider to release and achieve avoidance.

3. The seamless product dual-color mold as described in claim 1, characterized in that: The first wedge can move along the mold closing and mold opening direction and move synchronously with the first front mold core or the first rear mold core. After the first mold is opened, the first wedge disengages from the common slider. The second wedge can move along the mold closing and mold opening direction and move synchronously with the second front mold core or the second rear mold core. After the second mold is opened, the second wedge disengages from the common slider.

4. The seamless product dual-color mold as described in claim 1, characterized in that: The common slider has oblique guide holes corresponding to the first and second oblique wedges. After the first and second oblique wedges are inserted into the oblique guide holes, they can drive the common slider to slide and achieve pressing and releasing.

5. The seamless product dual-color mold as described in claim 1, characterized in that: The end face of the rear mold is provided with a partial forming surface for the hard plastic product and can support the hard plastic product after the first mold is separated.

6. The seamless product dual-color mold as described in claim 1, characterized in that: The end of the common slider is provided with a pressing surface facing the common rear mold and used to fit the top edge of the hard plastic product.

7. The seamless product dual-color mold as described in claim 1, characterized in that: The first mold and the second mold are perpendicular to the horizontal plane in the mold closing direction, so that the injection molded product after mold separation is in a vertical state; the first mold and the second mold are arranged in parallel, the common module is connected to a rotating mechanism and can move between the first mold and the second mold, and the rotation axis of the common module is parallel to the mold closing and mold separation direction.

8. The seamless product dual-color mold as described in claim 1, characterized in that: The common module consists of two sets and can move alternately between the first mold and the second mold.

9. The seamless product dual-color mold as described in claim 1, characterized in that: The common slider is provided with sliding damping, or the contact surface between the common slider and the common rear mold is a smooth surface and can be attracted when in contact.

10. A method for using a two-color mold for a seamless product, characterized in that, Includes the following steps: S1. Reset, the common module moves to the first station and is located between the first front mold core and the first rear mold core; S2. In the first mold closing, the first front mold core and the first rear mold core move towards each other to achieve mold closing. After mold closing, the first rear mold core is located in the mold hole of the common module, and a first molding cavity for hard plastic structure molding is formed between the first rear mold core, the common rear mold and the first front mold core. During the mold closing process, the first wedge moves along the mold closing direction and inserts into the inclined guide hole of the common slider, pushing the common slider to move outward, thereby avoiding collision and providing space for the first mold to close; S3. In a single injection, the first injection molding machine injects hard plastic material into the first molding cavity to complete the injection molding of the hard plastic structure. S4. First cooling: Cool and shape the hard plastic structure to ensure its structural stability and achieve demolding strength. S5. In one mold opening, the first front mold core and the first rear mold core move along the mold opening direction to achieve mold separation. After mold separation, the first rear mold core is located outside the mold hole of the common module, and the hard plastic structure remains on the common rear mold. During the mold parting process, the first wedge moves along the mold parting direction, causing the common slider to move inward and press the pressure surface at the end of the common slider against the upper edge of the hard plastic structure, thereby fixing the hard plastic product. Furthermore, after the mold parting is completed, the first wedge disengages from the common slider; S6, Shifting: The drive mechanism moves the common module, carrying the hard plastic product, to the second station and positions it between the second front mold core and the second rear mold core. S7. Secondary mold closing: The second front mold core and the second rear mold core move towards each other to achieve mold closing. After mold closing, the second rear mold core extends into the mold hole of the common rear mold, and a second molding cavity for molding soft rubber structure is formed between the second rear mold core, the common rear mold and the second front mold core. During the mold closing process, the second wedge moves along the mold closing direction and inserts into the inclined guide hole of the common slider, pushing the common slider to move outward, releasing the pressure on the edge of the hard plastic product, and providing space for the second mold to close; S8. Secondary injection: The second injection machine injects soft rubber material into the second molding cavity, so that it covers the surface of the hard rubber structure. S9. Secondary cooling: Cooling and shaping the soft rubber product to ensure that the soft rubber and hard rubber are fully bonded and reach the demolding strength. S10, Secondary mold opening: The second front mold core and the second rear mold core move in opposite directions to achieve mold separation. After mold separation, the second rear mold core is located outside the mold hole of the common rear mold, and the product with soft rubber covering hard rubber remains on the common rear mold. During the mold parting process, the second wedge moves along the mold parting direction and disengages from the common slider. S11. Unloading: The formed product is removed from the common rear mold by a robotic arm or air nozzle. S12, Reset, the drive mechanism drives the common module 3 back to the first station.

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