An injection-molded overmolded structure

Abstract

This utility model provides an injection-molded overmolded structure, including a first base component; a plug placed inside the first base component; and a second base component, with the first base component placed inside the second base component, and the second base component covering the first base component and the plug. The first base component, as an inner load-bearing structure, is formed by injection molding into an injection-molded material frame with a specific cavity. A weight is precisely embedded in a preset position inside the frame, and the plug and the weight are mechanically connected to fix the spatial position. The second base component uses a secondary injection molding process to overmolded material onto the outside of the assembled component, forming a continuous and dense protective layer. Through the overmolding structure design of the first and second base components, combined with the injection molding process, it effectively replaces traditional zinc alloy materials, avoiding lead pollution and oxidation corrosion problems, while simplifying the production process, reducing production costs, and offering advantages such as environmental safety, high durability, and improved production efficiency.

Description

Technical Field

[0001] This utility model relates to the field of bathroom accessory manufacturing technology, and in particular to an injection molding overmolded structure. Background Technology

[0002] Existing bathroom fixtures, such as faucets and mixing valves, primarily use zinc alloys for cooling and showering. This material has significant technical drawbacks: First, zinc alloys contain lead, which may cause lead pollution during use, posing a potential threat to human health. Second, zinc alloys are prone to oxidation, leading to rust after prolonged use and severely impacting product lifespan. Furthermore, the market price of zinc alloy raw materials fluctuates greatly, making it difficult to control production costs. Traditional manufacturing processes involve long molding cycles and complex mold structures, all of which hinder improvements in product quality and production efficiency. To address these issues, there is an urgent need to develop a new type of overmolded structure that improves material selection and manufacturing processes, ensuring product appearance quality while enhancing environmental performance and lifespan. Existing technologies urgently require improvement to address these problems. Summary of the Invention

[0003] To overcome the shortcomings of existing technologies, this utility model provides an injection molding overmolding structure, comprising:

[0004] First basic component;

[0005] A plug, wherein the plug is disposed within the first base member;

[0006] The second base component is placed inside the first base component, and the second base component covers the first base component and the plug.

[0007] As an improvement of this utility model, the first base component includes a main body, and a first storage slot and a second storage slot are provided on both sides of the main body, with the first storage slot and the second storage slot being symmetrically positioned.

[0008] As an improvement to this utility model, it also includes a weight-adding component, which is placed inside the first base and connected to the plug; the weight-adding component includes a first weight-adding element and a second weight-adding element, the first weight-adding element being placed inside the first storage slot and the second weight-adding element being placed inside the second storage slot.

[0009] As an improvement of this utility model, the main body is further provided with a third storage slot and a fourth storage slot, the third storage slot and the fourth storage slot being symmetrically positioned; the third storage slot is located on one side of the first storage slot and communicates with the first storage slot, the fourth storage slot is located on one side of the second storage slot and communicates with the second storage slot; the plug includes a first plug and a second plug, the first plug is placed in the third storage slot and connected to the first weight-adding member, and the second plug is placed in the fourth storage slot and connected to the second weight-adding member.

[0010] As an improvement of this utility model, the main body is further provided with a first storage cavity and a second storage cavity with corresponding positions. The first storage cavity is located on one side of the third storage slot and communicates with the third storage slot. The second storage cavity is located on one side of the fourth storage slot and communicates with the fourth storage slot. A first nut is placed in the first storage cavity and a second nut is placed in the second storage cavity.

[0011] As an improvement of this utility model, the main body is further provided with a third storage cavity, and the third storage cavity is provided with a plurality of through holes; the plurality of through holes includes a first through hole, which communicates with the first storage groove; the plurality of through holes includes a second through hole, which communicates with the second storage groove; the plurality of through holes includes a third through hole and a fourth through hole, which are symmetrically positioned; the plurality of through holes includes a fifth through hole, one end of which is located at the top of the main body and the other end of which is located at the bottom of the main body.

[0012] As an improvement to this utility model, it also includes a valve core, which is placed in the third storage cavity; the bottom of the valve core is provided with a first protrusion and a second protrusion with corresponding positions, the first protrusion is placed in the third through hole, and the second protrusion is placed in the fourth through hole.

[0013] As an improvement of this utility model, a cavity is provided inside the second base member, and the first base member is placed inside the cavity; a sixth through hole and a seventh through hole are provided on the second base member, and the sixth through hole and the seventh through hole are respectively located at both ends of the second base member; the sixth through hole corresponds to the position of the first storage cavity, and the seventh through hole corresponds to the position of the second storage cavity.

[0014] As an improvement of this utility model, the second base is further provided with a first connecting member, the valve core is placed inside the first connecting member, and the first connecting member is provided with an internal thread; the second base is further provided with a second connecting member, the second connecting member is placed at the bottom of the second base; the second connecting member is provided with an external thread, and a third nut is connected to the second connecting member.

[0015] As an improvement to this utility model, both the first base component and the second base component are integrally molded by injection molding.

[0016] The beneficial effects of this utility model are: This utility model provides an injection molding overmolding structure, which effectively replaces the traditional zinc alloy material by using the overmolding structure design of the first base component and the second base component, combined with the injection molding process, avoiding lead pollution and oxidation and corrosion problems. At the same time, it simplifies the production process, reduces production costs, and has the advantages of being environmentally friendly and safe, highly durable, and improving production efficiency. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the following description of the embodiments will be briefly introduced. 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.

[0018] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0019] Figure 1 This is a schematic diagram of the structure of this utility model;

[0020] Figure 2 This is a schematic diagram of the structure of this utility model with the second base and the third nut removed;

[0021] Figure 3 This is a schematic diagram of the structure of the second base component of this utility model;

[0022] Figure 4 This is an exploded view of this utility model;

[0023] Figure 5 This is a schematic diagram of the structure of the first basic component of this utility model;

[0024] Figure 6 This is a structural schematic diagram of the first base component of this utility model from another angle;

[0025] Figure 7 This is a structural schematic diagram of the first base component of this utility model from another angle;

[0026] Figure 8 This is a structural schematic diagram of the weight-adding material and the plug of this utility model;

[0027] Figure 9 This is a schematic diagram of the valve core of this utility model. Detailed Implementation

[0028] refer to Figures 1 to 9An injection molding overmolded structure includes a first base 1; a plug 3 placed inside the first base 1; and a second base 4, in which the first base 1 is placed inside the second base 4, and the second base 4 covers the first base 1 and the plug 3.

[0029] Through the above structure, the first base component 1 serves as the inner load-bearing structure, forming a frame with a specific cavity through injection molding. The weight 2 is precisely embedded in a preset position inside the frame, and the plug 3 forms a mechanical connection with the weight 2 to fix its spatial position. The second base component 4 uses a secondary injection molding process to coat the assembled component with molten injection molding material, forming a continuous and dense protective layer. This structure achieves functional modularity through a split design. The inner frame ensures the precise positioning of the metal parts, while the outer coating layer isolates moisture and oxygen from contacting the metal surface, and provides a uniform substrate for subsequent electroplating processes. Through the above technical solution, this application effectively eliminates the risk of lead leaching from bathroom accessories, blocks the direct contact path between metal parts and environmental media, and reduces the probability of failure caused by oxidation and corrosion. By combining the injection molding material matrix with the metal weight and plug, the amount of metal material used is reduced while maintaining the product's counterweight requirements, enhancing the controllability of production costs. The coating layer formed by the secondary injection molding process provides a uniform base for surface electroplating treatment, achieving the same appearance and texture as metal products; the injection molding material can be plastic, glass fiber, or other materials.

[0030] In this embodiment, the first base component 1 includes a main body, with a first placement groove 11 and a second placement groove 12 arranged on both sides of the main body. The first placement groove 11 and the second placement groove 12 are symmetrically positioned. The main body forms a mirror-distributed load-bearing structure through the symmetrically arranged first placement groove 11 and second placement groove 12 on both sides. The weight 2 is respectively embedded in the first placement groove 11 and the second placement groove 12. The symmetrical arrangement of the groove structure keeps the weight 2 in a balanced stress state during the injection molding process. The symmetrical design of the placement groove can counteract the eccentric force generated by the weight during the overmolding process, avoiding uneven overmolding thickness due to center of gravity shift. This ensures that the overmolding layer of the second base component 4 has a consistent stress distribution after cooling and solidification; ensures that the weight 2 is always in a predetermined position during the overmolding process, avoiding localized thinning or cracking of the overmolding layer due to installation misalignment; and improves the uniformity of the overmolding layer thickness, thereby improving the overall structural strength and service life of the product.

[0031] In this embodiment, a weight-adding component 2 is also included. The weight-adding component 2 is placed inside the first base component 1 and connected to the plug 3. The weight-adding component 2 includes a first weight-adding component 21 and a second weight-adding component 22. The first weight-adding component 21 is placed inside the first storage slot 11, and the second weight-adding component 22 is placed inside the second storage slot 12. During the injection molding stage of the main body of the first base component 1, the first storage slot 11 and the second storage slot 12 are formed simultaneously through the mold cavity. During the assembly process, when the first weight-adding component 21 is embedded in the first storage slot 11, its bottom surface contacts the bottom plane of the slot, its two sides form a clearance fit with the slot wall, and its top is exposed outside the slot opening. After the second weight-adding component 22 is embedded in the second storage slot 12 in the same manner, the two weight-adding components are symmetrically distributed about the central axis of the base component. During the secondary injection molding process, the molten injection molding material covers the exposed part of the weight-adding component, and the clamping force generated by the cooling and shrinkage of the injection molding material fixes the weight-adding component in the storage slot. Because the two weight-adding components have equal mass and are symmetrically arranged, the center of mass of the base component coincides with its geometric center, avoiding differences in the thickness of the overlay layer caused by uneven weight distribution. This achieves precise balancing and reliable fixation of the weight-adding components within the base component, solving the product vibration problem caused by assembly deviations in traditional integral weight-adding structures. At the same time, it avoids the defect of uneven shrinkage of the overlay layer caused by unilateral weight-adding, giving the overlay-molded product better dynamic balance performance and structural stability.

[0032] In this embodiment, the main body is further provided with a third storage slot 13 and a fourth storage slot 14, which are symmetrically positioned. The third storage slot 13 is located on one side of the first storage slot 11 and communicates with it, while the fourth storage slot 14 is located on one side of the second storage slot 12 and communicates with it. The plug 3 includes a first plug 31 and a second plug 32. The first plug 31 is placed in the third storage slot 13 and connected to the first weight-adding member 21, while the second plug 32 is placed in the fourth storage slot 14 and connected to the second weight-adding member 22. The lateral communication between the third storage slot 13 and the first storage slot 11 forms an L-shaped continuous space, and the lateral communication between the fourth storage slot 14 and the second storage slot 12 forms a mirror-symmetrical L-shaped continuous space. After the weight-adding member is placed into the first storage slot 11 and the second storage slot 12, the symmetrical layout of the third storage slot 13 and the fourth storage slot 14 provides an axially extended accommodating area for subsequent nut installation. During the secondary injection molding process, the weight-adding component is placed in the first storage slot 11 and the second storage slot 12, and the plug is placed in the third storage slot 13 and the fourth storage slot 14 to prevent the molten injection material from entering the first storage slot 11, the second storage slot 12, the third storage slot 13 and the fourth storage slot 14 and blocking the first and second water channels.

[0033] In this embodiment, the main body is further provided with a first storage cavity 15 and a second storage cavity 16 in corresponding positions. The first storage cavity 15 is located on one side of the third storage slot 13 and communicates with the third storage slot 13. The second storage cavity 16 is located on one side of the fourth storage slot 14 and communicates with the fourth storage slot 14. A first nut 5 is placed in the first storage cavity 15, and a second nut 6 is placed in the second storage cavity 16. During the injection molding stage of the injection molding material inner liner, the symmetrical cavity structure of the first storage cavity 15 and the second storage cavity 16 is pre-formed by the mold. During the assembly process, the first nut 5 and the second nut 6 are respectively placed in the corresponding storage cavities and positioned and calibrated through the communication channels with the third storage slot 13 and the fourth storage slot 14. During the secondary injection molding overmolding, the overmolding material forms a wrapping and fixing of the nuts through flow filling. The symmetrical cavity structure ensures that the metal connectors remain in a stable position during the injection molding process, avoiding the displacement problem caused by uneven force. It realizes the precise positioning and fixing of the metal connectors in the injection molding material matrix and avoids the risk of lead pollution from zinc alloy materials. The symmetrical cavity structure ensures uniform material flow during injection molding and prevents uneven coating thickness caused by misalignment of metal parts. The interconnected design of the storage cavity and storage slot simplifies the nut assembly process and solves the installation difficulties caused by the enclosed internal space of the injection molded material liner.

[0034] In this embodiment, the main body is further provided with a third storage cavity 17, and the third storage cavity 17 is provided with a plurality of through holes; the plurality of through holes include a first through hole 171, which communicates with the first storage groove 11; the plurality of through holes include a second through hole 172, which communicates with the second storage groove 12; the plurality of through holes include a third through hole 173 and a fourth through hole 174, which are symmetrically positioned; the plurality of through holes include a fifth through hole 175, one end of which is placed at the top of the main body and the other end of which is placed at the bottom of the main body; the first through hole 171, the first storage groove 11, the third storage groove 13 and the first storage cavity 15 communicate with each other to form a first waterway; the second through hole 172, the second storage groove 12, the fourth storage groove 14 and the second storage cavity 16 communicate with each other to form a second waterway.

[0035] The third storage cavity 17 is horizontally connected to the first storage groove 11 through the first through hole 171, which constrains the weight-added part with material pressure from both sides during injection molding, preventing lateral displacement. The symmetrical connection between the second through hole 172 and the second storage groove 12 further enhances the bidirectional fixing effect of the weight-added part. The symmetrical arrangement of the third through hole 173 and the fourth through hole 174 forms a support channel in the longitudinal direction. When the overmolding material is injected, the material flows along the inside of the through hole to form a continuous internal support structure, effectively dispersing the injection pressure. The vertical penetration characteristic of the fifth through hole 175 allows the overmolding material to fill evenly along the main body axis, avoiding molding defects caused by uneven material accumulation. As the core node of the through hole system, the third storage cavity 17 constructs a three-dimensional limiting system through a multi-directional interconnected channel network, realizing multi-dimensional fixing of the weight-added part within a limited space; it achieves multi-directional mechanical constraint of the weight-added part during injection molding, preventing displacement or tilting due to material flow pressure. The multi-dimensional interconnected through-hole system provides a uniform penetration path for the overmolding material, ensuring that the molded structure is free of pores or incomplete filling defects. The symmetrically arranged through-hole design balances the internal stress generated during injection molding, avoiding uneven overmolding thickness caused by local deformation. The vertically penetrating channels enhance the axial structural strength while providing installation interfaces for subsequent assembly components such as valve core 7.

[0036] In this embodiment, a valve core 7 is also included, which is placed in the third storage cavity 17. The bottom of the valve core 7 is provided with a first protrusion 71 and a second protrusion 72, which are positioned correspondingly. The first protrusion 71 is placed inside the third through hole 173, and the second protrusion 72 is placed inside the fourth through hole 174. During assembly, the valve core 7 is precisely placed into the defined space of the third storage cavity 17. At this time, the first protrusion 71 and the second protrusion 72 are inserted horizontally into the third through hole 173 and the fourth through hole 174, respectively. Because the two sets of protrusions and through holes are symmetrically distributed, when the valve core 7 is subjected to external force, the protrusions on both sides generate a uniform contact reaction force with the wall surface of the through hole, effectively counteracting the lateral displacement trend. Meanwhile, the depth of the through hole can be set to 1.2-1.5 times the length of the protrusion, ensuring an appropriate gap between the end of the protrusion and the bottom of the through hole. This guarantees smooth assembly while avoiding stress concentration caused by excessive constraint. It also solves the sealing failure problem caused by insufficient installation stability of the valve core 7. Through the symmetrically distributed protrusion and through hole insertion structure, the valve core 7 maintains precise alignment under dynamic operating conditions, preventing media leakage due to misalignment. Furthermore, this structural design creates a mechanical interlock between the valve core 7 and the base, achieving reliable fixation without additional fasteners, significantly improving the overall structural strength and service life of the product.

[0037] In this embodiment, a cavity 41 is provided inside the second base member 4, and the first base member 1 is placed inside the cavity 41. The second base member 4 is provided with a sixth through hole 42 and a seventh through hole 43, which are respectively located at both ends of the second base member 4. The sixth through hole 42 corresponds to the position of the first storage cavity 15, and the seventh through hole 43 corresponds to the position of the second storage cavity 16. During the secondary injection molding process, the first base member 1 is pre-placed inside the cavity 41 of the second base member 4. The gap between the inner wall of the cavity 41 and the outer wall of the first base member 1 is filled with injection molding material to form a coating layer. The cavity structure restricts the displacement of the first base member 1 under injection pressure. The sixth through hole 42 and the seventh through hole 43 correspond to the positions of the first storage cavity 15 and the second storage cavity 16, respectively, allowing external bolts to pass through the through holes and directly screw into the first nut 5 and the second nut 6. The coating material between the nut and the through hole forms a sealing layer, preventing moisture penetration and rusting of the nut. The symmetrical distribution of through holes at both ends ensures that when external loads are transmitted to the nut via bolts, the force is evenly distributed along the axis of the through holes to the rubber coating, preventing localized stress concentration that could lead to cracking of the rubber coating. This also solves the problem of uneven rubber coating caused by positioning deviations of the base component during secondary injection molding. Furthermore, the axial alignment of the pre-set through holes with the built-in nut ensures the assembly accuracy of the external connection structure, preventing loosening due to thread misalignment. The symmetrical through-hole design further reduces the shear stress on the rubber coating from external loads, preventing cracking due to localized stress concentration.

[0038] In this embodiment, the second base 4 is further provided with a first connector 44, and the valve core 7 is placed inside the first connector 44, which has an internal thread 441. The second base 4 is also provided with a second connector 45, which is placed at the bottom of the second base 4. The second connector 45 has an external thread 451 and is connected to a third nut 8. The valve core 7 is assembled into the cavity of the internal thread 441 of the first connector 44. The friction generated by the thread engagement restricts the displacement of the valve core 7 during the injection molding process, and the thread engagement gap forms multiple sealing surfaces. The external thread 451 of the second connector 45 forms an integral structure with the second base 4 during injection molding. The external thread 451 is directly screwed into the external pipe joint. The third nut 8 is screwed to the end of the external thread and pressed against the flange face of the pipe joint to form a mechanical locking structure to prevent loosening. This dual connection method allows the valve core 7 to be fixed inside the rubber coating layer, while providing an adjustable assembly reference for the external interface; it solves the problem of sealing failure caused by displacement of the valve core 7 during the rubber coating process, and improves the installation stability of the valve core 7 through the engagement of the internal thread 441; the mating structure of the external thread 451 and the third nut 8 enhances the external connection's ability to resist vibration and loosening.

[0039] In this embodiment, both the first base component 1 and the second base component 4 are integrally injection molded. The first base component 1 forms an inner liner structure with a storage groove and through holes through the initial injection molding. The positioning cavity of the weight-adding component 2 and the connecting structure of the plug 3 are integrated during the mold design stage. In the second injection molding process, molten injection molding material is injected into the mold cavity containing the first base component 1. Under pressure, the molten injection molding material wraps around the outer surface of the first base component 1 and fills its structural gaps. After cooling, a seamless composite structure is formed. This molding method, through the continuous implementation of two injection molding processes, enables the inner and outer layers to form a molecular-level bonding interface, replacing the mechanical connection between the metal matrix and the injection molding material coating layer in the traditional process. It effectively eliminates the risk of heavy metal precipitation caused by traditional zinc alloy matrix in bathroom product applications and prevents surface corrosion defects caused by oxidation of the matrix material. The continuous implementation of the injection molding process reduces raw material loss during production. The integrated manufacturing of complex functional structures is achieved through the optimized design of the mold structure, simplifying the assembly process of the matrix and coating layer in the traditional overmolding process.

[0040] The above description provides one or more embodiments in conjunction with specific content, but it is not intended that the specific implementation of this utility model is limited to these descriptions. Any methods or structures that are similar to or identical to those of this utility model, or any technical deductions or substitutions made based on the concept of this utility model, should be considered within the scope of protection of this utility model.

Claims

1. An injection-molded overmolded structure, characterized in that, include: First base component (1); A plug (3) is placed inside the first base member (1); The second base (4) is placed inside the first base (1), and the second base (4) covers the first base (1) and the plug (3).

2. The injection molding overmolding structure according to claim 1, characterized in that, The first base component (1) includes a main body, and a first storage slot (11) and a second storage slot (12) are provided on both sides of the main body. The first storage slot (11) and the second storage slot (12) are symmetrically positioned.

3. The injection molding overmolding structure according to claim 2, characterized in that, It also includes a weight-adding component (2), which is placed inside the first base (1) and connected to the plug (3); the weight-adding component (2) includes a first weight-adding component (21) and a second weight-adding component (22), the first weight-adding component (21) is placed inside the first storage slot (11), and the second weight-adding component (22) is placed inside the second storage slot (12).

4. The injection molding overmolding structure according to claim 3, characterized in that, The main body is also provided with a third storage slot (13) and a fourth storage slot (14), the third storage slot (13) and the fourth storage slot (14) are symmetrical in position; the third storage slot (13) is located on one side of the first storage slot (11) and communicates with the first storage slot (11), the fourth storage slot (14) is located on one side of the second storage slot (12) and communicates with the second storage slot (12); the plug (3) includes a first plug (31) and a second plug (32), the first plug (31) is placed in the third storage slot (13) and connected to the first weight-adding member (21), the second plug (32) is placed in the fourth storage slot (14) and connected to the second weight-adding member (22).

5. The injection molding overmolding structure according to claim 4, characterized in that, The main body is also provided with a first storage cavity (15) and a second storage cavity (16) in corresponding positions. The first storage cavity (15) is located on one side of the third storage slot (13) and communicates with the third storage slot (13). The second storage cavity (16) is located on one side of the fourth storage slot (14) and communicates with the fourth storage slot (14). A first nut (5) is placed in the first storage cavity (15), and a second nut (6) is placed in the second storage cavity (16).

6. The injection molding overmolding structure according to claim 2, characterized in that, The main body is also provided with a third storage cavity (17), and the third storage cavity (17) is provided with a plurality of through holes; the plurality of through holes include a first through hole (171), which communicates with the first storage groove (11); the plurality of through holes include a second through hole (172), which communicates with the second storage groove (12); the plurality of through holes include a third through hole (173) and a fourth through hole (174), which are symmetrically positioned; the plurality of through holes include a fifth through hole (175), one end of which is placed at the top of the main body and the other end of which is placed at the bottom of the main body.

7. The injection molding overmolding structure according to claim 6, characterized in that, It also includes a valve core (7), which is placed in the third storage cavity (17); the bottom of the valve core (7) is provided with a first protrusion (71) and a second protrusion (72) with corresponding positions, the first protrusion (71) is placed in the third through hole (173), and the second protrusion (72) is placed in the fourth through hole (174).

8. The injection molding overmolding structure according to claim 5, characterized in that, The second base (4) is provided with a cavity (41), and the first base (1) is placed in the cavity (41); the second base (4) is provided with a sixth through hole (42) and a seventh through hole (43), the sixth through hole (42) and the seventh through hole (43) are respectively located at both ends of the second base (4); the sixth through hole (42) corresponds to the position of the first storage cavity (15), and the seventh through hole (43) corresponds to the position of the second storage cavity (16).

9. The injection molding overmolding structure according to claim 7, characterized in that, The second base (4) is also provided with a first connector (44), the valve core (7) is placed inside the first connector (44), and the first connector (44) is provided with an internal thread (441); the second base (4) is also provided with a second connector (45), the second connector (45) is placed at the bottom of the second base (4); the second connector (45) is provided with an external thread (451), and a third nut (8) is connected to the second connector (45).

10. The injection molding overmolding structure according to claim 1, characterized in that, Both the first base component (1) and the second base component (4) are integrally molded by injection molding.

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