Sequential ejection structure for injection molded silicone products

Abstract

The utility model relates to the technical fields of injection mold, especially to a sequential demolding structure of injection molding silica gel product, including front mould assembly, rear mould assembly and core assembly, rear mould assembly is equipped with rear mould plate and rear mould kernel, front mould assembly is equipped with front mould plate and front mould kernel, and the inner wall of mould kernel through -hole is equipped with casing step, rear mould kernel includes mould kernel boss, the end of mould kernel boss and the inner top wall of hard glue casing body are in abutment, and the outer side wall and the inner side wall of hard glue casing body are inlaid, the end of mould kernel boss is equipped with mould kernel recess, and core assembly includes core rod, and one end of core rod passes through mould kernel boss and extends to mould kernel recess. In summary, the structure design is reasonable, and the forming precision, demolding safety and production efficiency are considered, the technical limitation of traditional rubber coating process in the complex soft glue structure of hard glue casing body inner top wall forming is broken through, and reliable mould solution scheme is provided for the large -scale production of high -precision composite injection molding product.

Description

Technical Field

[0001] This utility model relates to the technical field of injection molds, and in particular to a sequential demolding structure for injection molded silicone products. Background Technology

[0002] In the field of injection molding, the two-stage injection molding (overmolding) process is widely used in the production of electronic components, medical devices, and automotive parts because it can achieve a strong bond between a rigid plastic substrate and a soft plastic functional layer. This process typically involves first injection molding a rigid plastic part (such as a shell structure made of PP, ABS, or PC) using a first mold. After the rigid plastic part cools and is demolded, it is placed as an insert into a second mold (overmolding mold). Then, a soft material (such as thermoplastic elastomers like TPE, TPU, or TPV, or liquid silicone rubber LSR) is injected into the second mold, bonding the soft material to the surface of the rigid plastic part to form a composite product that combines the structural strength of rigid plastic with the tactile feel and cushioning properties of soft plastic.

[0003] However, when the product design requires injection molding of a soft rubber core into the top wall inside a hard rubber shell (especially when the soft rubber core needs to have complex structures such as clearance holes and concave and convex teeth), traditional overmolding molds and demolding processes face significant technical bottlenecks: Insufficient cavity positioning accuracy: After the hard plastic shell is placed into the overmolding mold as an insert, its axial and radial positions must be precisely fixed to avoid deviation in the molding position of the soft plastic core due to shell offset during injection molding. Traditional molds often use simple bosses or locating pins for limiting, which are difficult to adapt to the special molding space of the inner top wall of the hard plastic shell, and are prone to problems such as poor fit between the soft plastic core and the inner wall of the hard plastic shell, and glue overflow.

[0004] High Risk of Demolding Damage Due to Complex Soft Rubber Structures: To enhance the functional performance of soft rubber cores (such as increasing deformation capacity and improving friction with mating components), the outer wall of the soft rubber core is often designed with a first soft tooth, and the inner wall of the clearance hole is often designed with a second soft tooth. In traditional processes, the core rod used to form the clearance hole is often fixedly connected to the rear mold core. During demolding, the front mold assembly and the rear mold core separate simultaneously, causing the first soft tooth of the soft rubber core to be squeezed by the first groove of the mold core groove, and the second soft tooth to be squeezed by the second groove of the core rod, both from the inside and outside. Due to the low strength of the soft material itself, the extrusion force generated by simultaneous demolding can easily cause the soft teeth to be strained, deformed, or even broken, seriously affecting the product qualification rate and service life.

[0005] Poor stability of the core rod: During the injection molding process, the core rod needs to withstand the impact pressure of the molten soft rubber. If the core rod is only fixed on one side (such as only connected to the rear mold core), radial movement is likely to occur, resulting in deviation of the diameter of the soft rubber inner core clearance hole and uneven hole wall, which further reduces the molding accuracy of the product.

[0006] In view of the shortcomings of the above-mentioned traditional processes, there is no integrated mold structure in the existing technology that can simultaneously solve the problems of precise molding of soft rubber core on the top wall of hard rubber shell, non-destructive demolding of complex soft tooth structure and stable positioning of core rod. There is an urgent need to propose a special sequential demolding structure that is suitable for this type of product in order to break through the production bottleneck and meet the market demand for high-precision, complex structure rubber-coated products. Utility Model Content

[0007] To overcome the shortcomings mentioned above, this utility model aims to provide a technical solution that can solve the above problems.

[0008] This utility model provides a sequential demolding structure for injection-molded silicone products, including a front mold assembly, a rear mold assembly, and a core assembly. The rear mold assembly has a rear template and a rear core, and the front mold assembly has a front template and a front core. The front core has a core through hole, and the inner wall of the core through hole has a housing step facing the front mold assembly. The housing step is used to accommodate a hard plastic housing, and the open end of the hard plastic housing faces the rear mold assembly. The rear core includes a core protrusion, which is positioned corresponding to the core through hole and extends into the core through hole. The opening end of the rigid plastic shell abuts against the inner top wall of the rigid plastic shell, and the outer side wall fits against the inner side wall of the rigid plastic shell, so that the opening end of the rigid plastic shell is fitted onto the end of the mold core protrusion; the end of the mold core protrusion is provided with a mold core groove, and the core assembly includes a core rod, one end of which passes through the mold core protrusion and extends into the mold core groove. The mold core groove, the core rod, and the inner top wall of the rigid plastic shell together define an injection molding cavity for injection molding a soft plastic core into the inner top wall of the rigid plastic shell.

[0009] Furthermore: the inner wall of the mold core groove is provided with a first tooth groove for forming the first soft tooth of the outer wall of the soft rubber core; the end of the core rod extending into the mold core groove is provided with a second tooth groove for forming the second soft tooth of the inner wall of the soft rubber core clearance hole.

[0010] Furthermore: the rear mold core has a rod through hole corresponding to the core rod, the core rod passes through the rear mold core and forms a sliding connection with the rod through hole; the core assembly also has a core base, the end of the core rod away from the injection cavity is fixed to the core base, the rear mold plate has a first groove corresponding to the core base, the first groove is used to accommodate the core base when the mold is closed; the rear mold core has a second groove corresponding to the core base, the second groove is used to accommodate the core base when the mold is opened.

[0011] Furthermore: the front mold assembly is provided with a sprue plate and a sprue insert. The sprue plate is fixed to the side of the front mold plate facing away from the rear mold assembly by fasteners. The sprue plate is equipped with a gating system for injecting molten plastic into the injection cavity. The sprue insert is assembled between the front mold core and the sprue plate and is provided with an auxiliary runner for assisting the gating system in injecting molten plastic. The side of the sprue insert facing the front mold core is also provided with an auxiliary protrusion for abutting the end of the core rod extending into the groove of the mold core.

[0012] Furthermore, the side of the sprue insert facing the front mold core is also provided with a shallow relief groove and a deep relief groove. The shallow relief groove is set to correspond to the outer top wall of the hard plastic shell, and the deep relief groove is set to correspond to the outer top hollow column of the hard plastic shell.

[0013] Furthermore: the front template is provided with a mold core step, which is used to position the front mold core and provide demolding driving force when the mold is opened, so as to drive the front mold core to disengage from the mold core through hole.

[0014] Compared with the prior art, the beneficial effects of this utility model are: ① Improve the molding precision of the soft rubber core and ensure product consistency. The front mold core limits the side wall of the hard rubber shell through the shell steps on the inner wall of the mold core through hole. The mold core protrusion of the rear mold core penetrates into the opening end of the hard rubber shell and abuts against its inner side wall and inner top wall. At the same time, the shallow groove of the gate insert axially positions the outer top wall of the hard rubber shell and the deep groove avoids the outer top hollow column, forming a multi-dimensional positioning structure of "inner wall steps + protrusion fitting + outer wall clearance", which accurately fixes the axial and radial position of the hard rubber shell and avoids shell displacement during injection molding. The two ends of the core rod abut against the first groove of the rear mold plate through the core base and abut against and limit through the gate insert auxiliary protrusion, realizing bidirectional fixation of the core rod, effectively resisting the impact pressure of molten soft rubber, preventing the core rod from moving, ensuring the accuracy of the soft rubber core clearance hole diameter and the flatness of the hole wall, and significantly improving the product molding consistency.

[0015] ② Achieving non-destructive demolding of complex soft rubber structures and improving product qualification rate: An innovative sliding connection structure between the core rod and the rear mold core is designed (the core rod passes through the rod through hole of the rear mold core and can slide along the through hole). Combined with the first groove of the rear mold plate and the second groove of the rear mold core to accommodate and limit the core base, "step-by-step sequential demolding" is achieved: In the initial stage of demolding, the core rod moves synchronously with the soft rubber core, only completing the separation of the first soft tooth from the first tooth groove, avoiding simultaneous force on the second soft tooth; after the first soft tooth is completely separated, the core base abuts against the top of the second groove, the core rod stops moving, and then the second soft tooth separates from the second tooth groove. Step-by-step demolding allows the soft teeth of the soft rubber core to fully deform during demolding, completely eliminating the extrusion damage caused by synchronous demolding, reducing the soft tooth damage rate by more than 90%, and significantly improving the product qualification rate.

[0016] ③ Simplify the operation process and improve production efficiency. The front mold plate and the sprue plate, the front mold core and the sprue insert can be relatively separated and moved. After the mold is opened, the through hole of the mold core is in an open state, which makes it easy for operators to quickly place hard plastic inserts and take out the molded products, reducing the waiting time for mold opening and closing. The structural design of each component of the mold (such as the front mold core, the rear mold core, the core rod and the sprue insert) is adapted to standardized processing and assembly. It can be put into mass production without complicated debugging, reducing equipment debugging costs and production cycle.

[0017] ④ Enhance the reliability of the connection between the soft rubber core and the hard rubber shell. The top wall of the hard rubber shell is equipped with a through hollow column. The inner hollow column protruding from the inner top wall is wrapped and clamped by the soft rubber core during the injection molding process, forming a "mechanical interlocking" structure. Compared with the traditional connection method that only relies on surface bonding, the connection strength between the soft rubber core and the inner top wall of the hard rubber shell is increased by more than 30%, effectively avoiding the risk of the soft rubber core falling off or separating during long-term use.

[0018] In summary, this utility model has a reasonable structural design that balances molding accuracy, demolding safety, and production efficiency. It effectively breaks through the technical limitations of traditional overmolding processes in forming complex soft rubber structures on the top wall of a hard rubber shell, providing a reliable mold solution for the large-scale production of high-precision composite injection molded products.

[0019] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the overall structure of this utility model; Figure 2 This is a structural diagram of the front mold plate, rear mold core, and front mold core of this utility model in a separated state; Figure 3 This is a structural schematic diagram of the rear mold core, front mold core, and sprue insert of this utility model in a separated state; Figure 4 This is a structural schematic diagram of the sprue insert, core rod, and core base of this utility model; Figure 5 This is a schematic diagram of the structure of the hard plastic shell and the front mold core of this utility model in a separated state; Figure 6 This is a schematic diagram of the structure of the present invention with the hard plastic shell and the soft plastic core separated from each other. Figure 7 This is a cross-sectional schematic diagram of the sprue plate, front template, and rear template of this utility model; Figure 8 This is a cross-sectional schematic diagram of the mold core protrusion of this utility model in the demolding state; Figure 9 This is a cross-sectional schematic diagram of the core rod of this utility model in the demolding state.

[0022] The reference numerals and names in the figure are as follows: 10. Front mold assembly; 11. Front template; 12. Mold core step; 13. Front mold core; 14. Mold core through hole; 15. Shell step; 20. Sprue plate; 21. Sprue insert; 22. Auxiliary protrusion; 23. Shallow clearance groove; 24. Deep clearance groove; 30. Rear mold assembly; 31. Rear template; 32. First groove; 33. Rear mold core; 34. Second groove; 35. Mold core protrusion; 36. Mold core groove; 37. First tooth groove; 40. Core assembly; 41. Core rod; 42. Second tooth groove; 43. Core base; 50. Hard plastic shell; 51. Outer ejector hollow column; 52. Inner ejector hollow column; 53. Soft plastic inner core; 54. First soft tooth; 55. Clearance hole; 56. Second soft tooth; 61. Gating system; 62. Ejection system. Detailed Implementation

[0023] The technical solutions in the embodiments of this utility model will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0024] Please see Figures 1 to 9In this embodiment of the present invention, a sequential demolding structure for injection-molded silicone products includes a front mold assembly 10, a rear mold assembly 30, and a core assembly 40. The rear mold assembly 30 is provided with a rear template 31 and a rear core 33. The front mold assembly 10 is provided with a front template 11 and a front core 13. The front core 13 is provided with a core through hole 14. The inner wall of the core through hole 14 is provided with a housing step 15 facing the front mold assembly 10. The housing step 15 is used to accommodate a hard plastic housing 50 and to make the open end of the hard plastic housing 50 face the rear mold assembly 30. The rear core 33 includes a core protrusion 35, which is provided corresponding to the core through hole 14 and extends into the core. The through hole 14 passes through the opening end of the hard plastic shell 50, and its end abuts against the inner top wall of the hard plastic shell 50. Its outer side wall fits against the inner side wall of the hard plastic shell 50, so that the opening end of the hard plastic shell 50 is fitted onto the end of the mold core protrusion 35. The end of the mold core protrusion 35 is provided with a mold core groove 36. The core assembly 40 includes a core rod 41. One end of the core rod 41 passes through the mold core protrusion 35 and extends into the mold core groove 36. The mold core groove 36, the core rod 41 and the inner top wall of the hard plastic shell 50 together define an injection molding cavity for injection molding a soft plastic core 53 into the inner top wall of the hard plastic shell 50.

[0025] Specifically, the secondary injection molding process generally involves first injection molding a rigid plastic part in a first mold. After cooling, the rigid plastic part is removed and placed into a second mold (also known as an overmolding mold). In the second mold, a soft plastic material is injection molded and bonded to the rigid plastic part. For example, a rigid plastic shell 50 is first injection molded using a standard injection molding process using rigid plastics (such as PP, ABS, PC, etc.). This hard plastic shell 50 is then used as an insert and placed into the cavity of another injection mold. Next, a soft plastic (such as thermoplastic elastomers like TPE, TPU, TPV, or liquid silicone rubber LSR) is injected into this mold, causing it to be injection molded again onto the inner top wall of the rigid plastic shell 50, forming a soft plastic core 53 firmly bonded to the rigid plastic. Because the soft plastic core 53 needs to be injection molded onto the inner top wall of the rigid plastic shell 50, the traditional overmolding process cannot accomplish this well, thus requiring improvement.

[0026] This invention facilitates the placement of the pre-molded hard plastic shell 50 by providing a mold core through hole 14 in the front mold core 13 and a shell step 15 on the inner side wall of the mold core through hole 14. Simultaneously, a mold core protrusion 35 is provided in the rear mold core 33, extending into the mold core through hole 14 and penetrating the opening end of the hard plastic shell 50. The outer side wall of the mold core protrusion 35 abuts against the inner side wall of the hard plastic shell 50, while the end of the mold core protrusion 35 abuts against the inner top wall of the hard plastic shell 50, forming an assembly structure where the opening end of the hard plastic shell 50 is fitted onto the end of the mold core protrusion 35. This creates a basic cavity structure through the mold core groove 36 at the end of the mold core protrusion 35.

[0027] Since the soft rubber core 53 has a clearance hole 55, a core rod 41 is provided in the core assembly 40. The core rod 41 passes through the mold core protrusion 35 and extends into the mold core groove 36, cooperating with the inner sidewall of the mold core groove 36 to form part of the injection cavity, which is used to guide and limit the flow of molten plastic, thereby forming the clearance hole 55 of the soft rubber core 53.

[0028] Therefore, through the cooperation of the shell step 15 of the front mold core 13, the mold core protrusion 35 of the rear mold core 33, the mold core groove 36 of the mold core protrusion 35, and the core rod 41, the corresponding injection cavity is formed, ensuring the precise molding of the soft rubber core 53 on the top wall of the hard rubber shell 50.

[0029] like Figure 2 and Figure 4 As shown, preferably, the inner wall of the mold core groove 36 is provided with a first tooth groove 37 for forming a first soft tooth 54 on the outer wall of the soft rubber core 53; the end of the core rod 41 extending into the mold core groove 36 is provided with a second tooth groove 42 for forming a second soft tooth 56 on the inner wall of the soft rubber core 53 clearance hole 55.

[0030] Specifically, to increase the deformation capacity and friction of the soft rubber core 53, it is preferable to provide soft teeth on the outer side wall of the soft rubber core 53, and the inner side wall of its clearance hole 55 is also provided with soft teeth. In order to injection mold the corresponding soft teeth, a first tooth groove 37 needs to be provided on the inner side wall of the mold core groove 36, and a second tooth groove 42 needs to be provided at the end of the core rod 41 that extends into the mold core groove 36, so as to injection mold the corresponding first soft teeth 54 and second soft teeth 56.

[0031] Secondly, on the inner wall of the mold core groove 36, multiple first tooth grooves 37 are evenly distributed along the axial direction of the mold core groove 36, thereby forming multiple first soft teeth 54 on the outer wall of the soft rubber inner core 53. Similarly, multiple second tooth grooves 42 are also provided on the outer wall of one end of the core rod 41, thereby forming multiple second soft teeth 56 on the inner wall of the clearance hole 55 of the soft rubber inner core 53.

[0032] like Figures 2 to 4 As shown, preferably, the rear mold core 33 has a rod through hole corresponding to the core rod 41, and the core rod 41 passes through the rear mold core 33 and forms a sliding connection with the rod through hole; the core assembly 40 also has a core base 43, and the end of the core rod 41 away from the injection cavity is fixed to the core base 43; the rear mold plate 31 has a first groove 32 corresponding to the core base 43, and the first groove 32 is used to accommodate the core base 43 when the mold is closed; the rear mold core 33 has a second groove 34 corresponding to the core base 43, and the second groove 34 is used to accommodate the core base 43 when the mold is opened.

[0033] In the traditional structure, the core rod 41 is usually fixedly connected to the rear mold core 33 to form the second soft tooth 56. After injection molding, it is necessary to demold the integral product formed by the hard plastic shell 50 and the soft plastic core 53. The shell step 15 in the mold core through hole 14 of the front mold core 13 drives the side wall of the hard plastic shell 50 in the mold opening direction, so that the inner top wall of the hard plastic shell 50 drives the soft plastic core 53 to move for demolding, so that the soft plastic core 53 is separated from the injection cavity.

[0034] Since there is a limiting relationship between the first soft tooth 54 on the outer side wall of the soft rubber core 53 and the first tooth groove 37 of the mold core groove 36, and between the second soft tooth 56 on the inner side wall of the clearance hole 55 and the second tooth groove 42 of the core rod 41, if the front mold and the rear mold separate at the same time during the normal demolding process, the first soft tooth 54 and the second soft tooth 56 will be squeezed from both the inner and outer sides at the same time, which can easily cause the soft teeth to be pulled or damaged.

[0035] Therefore, in this invention, a rod through hole is provided on the rear mold core 33, and the core rod 41 passes through the rod through hole and slides with it. During the demolding process, the core rod 41 can move synchronously with the soft rubber inner core 53, thereby avoiding simultaneous force between the first soft tooth 54 and the first tooth groove 37, and between the second soft tooth 56 and the second tooth groove 42, realizing step-by-step demolding of the soft teeth and reducing the risk of dragging.

[0036] First, the demolding operation is performed between the first soft tooth 54 on the outer wall of the soft rubber core 53 and the first tooth groove 37 in the mold core groove 36. At this time, the core rod 41 remains on the inner wall of the clearance hole 55 of the soft rubber core 53 and demolds synchronously with the soft rubber core 53. That is, the core rod 41 drives the core base 43 to move into the second groove 34 of the rear mold core 33, so as not to restrict the demolding movement of the core rod 41.

[0037] Secondly, after the first soft tooth 54 and the first tooth groove 37 have completely separated, the demolding process continues, that is, the front mold assembly 10 and the rear mold assembly 30 continue to separate, and the demolding operation between the second soft tooth 56 on the inner wall of the soft rubber core 53's clearance hole 55 and the second tooth groove 42 on the core rod 41 continues. At this time, the top surface of the core base 43 abuts against the top of the second groove 34, so that the rear mold core 33 limits the core base 43, preventing the core rod 41 from continuing to move with the soft rubber core 53. Therefore, the core rod 41 can be smoothly removed from the clearance hole 55 of the soft rubber core 53. Through the above structural settings, the first soft tooth 54 and the second soft tooth 56 of the soft rubber core 53 can be demolded in sequence, so that the soft teeth can undergo greater deformation during demolding, preventing the risk of dragging.

[0038] like Figures 3 to 4 As shown, preferably, the front mold assembly 10 is provided with a sprue plate 20 and a sprue insert 21. The sprue plate 20 is fixed to the side of the front mold plate 11 facing away from the rear mold assembly 30 by fasteners. The sprue plate 20 is equipped with a gating system 61 for injecting molten plastic into the injection cavity. The sprue insert 21 is assembled between the front mold core 13 and the sprue plate 20 and is provided with an auxiliary runner for assisting the gating system 61 in injecting molten plastic. The side of the sprue insert 21 facing the front mold core 13 is also provided with an auxiliary protrusion 22 for abutting the end of the core rod 41 extending into the mold core groove 36.

[0039] Specifically, to improve the stability of the core rod 41 after mold closing, a limiting structure is preferably provided at the end of its extension into the mold core groove 36. This is achieved by using the auxiliary protrusion 22 of the sprue insert 21 to abut and limit its end. Essentially, after mold closing, one end of the core rod 41 is fixed to the core base 43, and the bottom of the core base 43 abuts against the bottom of the first groove 32 of the rear mold plate 31. Simultaneously, the other end of the core rod 41 extending into the mold core groove 36 is abutted by the auxiliary protrusion 22 of the sprue insert 21. Therefore, the abutment at both ends of the core rod 41 creates a stable limiting effect, fixing the core rod 41 within the injection cavity. In the mold-closed state, one end of the core rod 41 is fixed to the core base 43 and abuts against the bottom of the first groove 32 of the rear mold plate 31, while the other end extends into the mold core groove 36 and is abutted by the auxiliary protrusion 22 of the sprue insert 21, thus achieving limiting at both ends.

[0040] Secondly, in order to place the hard plastic shell 50 before injection molding and to remove the injection molded product after mold opening, preferably, the front mold plate 11 and the sprue plate 20 can be relatively separated and moved, and the front mold core 13 and the sprue insert 21 can also be relatively separated and moved, so that the mold core through hole 14 of the front mold core 13 is in an open state, which facilitates material feeding and unloading.

[0041] like Figure 4As shown, preferably, the side of the sprue insert 21 facing the front mold core 13 is also provided with a shallow relief groove 23 and a deep relief groove 24. The shallow relief groove 23 is provided corresponding to the outer top wall of the hard plastic shell 50, and the deep relief groove 24 is provided corresponding to the outer top hollow column 51 of the hard plastic shell 50.

[0042] Specifically, a through-type hollow column is provided on the top wall of the hard plastic shell 50. The portion protruding from the outer top wall is designated as the outer hollow column 51, used to assist in the installation or connection of the hard plastic shell 50 to external equipment. The portion protruding from the inner top wall is designated as the inner hollow column 52, used to assist in the injection molding connection of the soft plastic core 53. That is, during the injection molding process, the soft plastic core 53 clamps the inner hollow column 52, thereby strengthening the connection between the soft plastic core 53 and the inner top wall of the hard plastic shell 50. The shallow clearance groove 23 and the deep clearance groove 24 are designed to avoid the hollow column on the top wall of the hard plastic shell 50, ensuring mold closing accuracy and product structural integrity.

[0043] Secondly, in order to avoid the outer hollow ejector pin 51 of the hard plastic shell 50 during the injection molding process, preferably, a deep relief groove 24 is provided on the side of the sprue insert 21 facing the front mold core 13, so that the outer hollow ejector pin 51 passes through the deep relief groove 24 to achieve the relief effect. Similarly, a shallow relief groove 23 can also be provided to avoid and limit the top wall of the hard plastic shell 50, so that after the mold is closed, the top wall of the hard plastic shell 50 is just accommodated in the shallow relief groove 23. This not only abuts against the top wall of the hard plastic shell 50 to ensure that its axial position is in the preset position, but also limits the outer wall of the hard plastic shell 50 through the inner side wall of the shallow relief groove 23 to ensure that its radial position is in the preset position.

[0044] like Figure 2 As shown, preferably, the front template 11 is provided with a mold core step 12 for positioning the front mold core 13 and providing demolding driving force when the mold is opened, so as to drive the front mold core 13 to disengage from the mold core through hole 14.

[0045] Specifically, a cavity is provided in the center of the front mold plate 11 to accommodate the front mold core 13 and the rear mold core 33. To assemble and drive the front mold core 13, a mold core step 12 is provided in the direction facing the front mold core 13 from the cavity, so that the bottom edge of the front mold core 13 abuts against the mold core step 12 when the mold is closed, forming an assembly limit. During the mold opening stage, after the front mold plate 11 performs the mold opening action, the mold core step 12 drives the front mold core 13 in the demolding direction, causing the front mold core 13 to move during demolding.

[0046] In addition, it also includes corresponding components and structures of existing injection molds such as ejection system 62, guiding system, cooling system, and venting system, so as to form an integral injection mold.

[0047] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this invention.

Claims

1. A sequential demolding structure for injection-molded silicone products, characterized in that, The assembly includes a front mold assembly (10), a rear mold assembly (30), and a core assembly (40). The rear mold assembly (30) has a rear template (31) and a rear core (33). The front mold assembly (10) has a front template (11) and a front core (13). The front core (13) has a core through hole (14). The inner wall of the core through hole (14) has a housing step (15) facing the front mold assembly (10). The housing step (15) is used to accommodate a hard plastic housing (50) and to make the open end of the hard plastic housing (50) face the rear mold assembly (30). The rear core (33) includes a core protrusion (35). The core protrusion (35) is provided corresponding to the core through hole (14) and extends into the core through hole (14). The opening end of the hard plastic shell (50) abuts against the inner top wall of the hard plastic shell (50), and the outer side wall fits against the inner side wall of the hard plastic shell (50), so that the opening end of the hard plastic shell (50) is fitted onto the end of the mold core protrusion (35); the end of the mold core protrusion (35) is provided with a mold core groove (36), and the core assembly (40) includes a core rod (41). One end of the core rod (41) passes through the mold core protrusion (35) and extends into the mold core groove (36). The mold core groove (36), the core rod (41) and the inner top wall of the hard plastic shell (50) together define an injection cavity for injection molding a soft plastic core (53) on the inner top wall of the hard plastic shell (50).

2. The sequential demolding structure for injection-molded silicone products according to claim 1, characterized in that, The inner wall of the mold core groove (36) is provided with a first tooth groove (37) for forming the first soft tooth (54) on the outer wall of the soft rubber core (53); the end of the core rod (41) extending into the mold core groove (36) is provided with a second tooth groove (42) for forming the second soft tooth (56) on the inner wall of the soft rubber core (53) clearance hole (55).

3. The sequential demolding structure for injection-molded silicone products according to claim 1, characterized in that, The rear mold core (33) has a rod through hole corresponding to the core rod (41). The core rod (41) passes through the rear mold core (33) and forms a sliding connection with the rod through hole. The core assembly (40) also has a core base (43). The end of the core rod (41) away from the injection cavity is fixed to the core base (43). The rear mold plate (31) has a first groove (32) corresponding to the core base (43). The first groove (32) is used to accommodate the core base (43) when the mold is closed. The rear mold core (33) has a second groove (34) corresponding to the core base (43). The second groove (34) is used to accommodate the core base (43) when the mold is opened.

4. The sequential demolding structure for injection-molded silicone products according to claim 1, characterized in that, The front mold assembly (10) is provided with a sprue plate (20) and a sprue insert (21). The sprue plate (20) is fixed to the side of the front mold plate (11) facing away from the rear mold assembly (30) by fasteners. The sprue plate (20) is equipped with a gating system (61) for injecting molten plastic into the injection cavity. The sprue insert (21) is assembled between the front mold core (13) and the sprue plate (20) and is provided with an auxiliary runner for assisting the gating system (61) in injecting molten plastic. The side of the sprue insert (21) facing the front mold core (13) is also provided with an auxiliary protrusion (22) for abutting the end of the core rod (41) extending into the mold core groove (36).

5. The sequential demolding structure for injection-molded silicone products according to claim 4, characterized in that, The sprue insert (21) is provided with a shallow relief groove (23) and a deep relief groove (24) on the side facing the front mold core (13). The shallow relief groove (23) is provided corresponding to the outer top wall of the hard plastic shell (50), and the deep relief groove (24) is provided corresponding to the outer top hollow column (51) of the hard plastic shell (50).

6. The sequential demolding structure for injection-molded silicone products according to claim 1, characterized in that, The front template (11) is provided with a mold core step (12) for positioning the front mold core (13) and providing demolding driving force when the mold is opened, so as to drive the front mold core (13) to disengage from the mold core through hole (14).

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