Injection molding method of sealing ring for nail gun

Abstract

The invention discloses an injection molding method of a sealing ring for a nail gun, which comprises the following steps: injecting a first thermoplastic raw material into a first mold, and carrying out injection molding to obtain a sealing outer ring piece; a protruding part is formed on the inner ring face of the sealing outer ring piece. The rubber raw materials are treated through melting and wire drawing, rubber fibers are obtained, the protruding parts are coated with an adhesive, and the rubber fibers are attached to the protruding parts in the circumferential direction of the sealing outer ring piece; the rubber fibers are arranged on the protruding part at intervals in the axial direction of the sealing outer ring piece. Filling metal powder between two adjacent rubber fibers to form a metal layer; and the sealing outer ring piece is put into a second mold, a second thermoplastic raw material is injected, a sealing inner ring piece is obtained on the protruding part through injection molding, and the sealing outer ring piece and the sealing inner ring piece are connected to form the sealing ring for the nail gun. According to the scheme, the gaps are filled with the rubber fibers, so that the sealing effect is improved, and meanwhile, the rubber fibers are arranged on the protruding parts at intervals, so that the buffering effect is achieved during operation of the nail gun.

Description

Technical Field

[0001] The invention relates to the technical field of injection molding, and in particular to an injection molding method of a sealing ring for a nail gun. Background Art

[0002] The injection molding process is a manufacturing technology that uses heating and high pressure to inject plastic or other fusible materials into a mold to form a shape. It is widely used in the fields of automobiles, electronics, medical devices, and industrial seals. The traditional injection molding process mainly relies on the fluidity and cooling solidification characteristics of a single material, and various parts, such as sealing rings, are formed through one-time or multiple injection molding. However, for nail guns, the high-frequency and high-pressure environment in which they are located places higher requirements on sealing rings, but conventional injection molding processes are difficult to further improve sealing and durability; specifically, because nail guns need to withstand instantaneous high pressure and repeated mechanical shocks during operation, ordinary injection molding sealing rings often have limited elastic recovery ability of the material, resulting in reduced sealing performance. At the same time, the wear resistance and high temperature resistance of a single material are weak, making the sealing ring prone to wear, aging or deformation after long-term use, resulting in gas leakage or sealing failure.

[0003] On this basis, technicians in this field proposed dual-mold injection molding, that is, injecting two different materials into the same mold in sequence, so that the product has multiple material properties in one molding process, further improving the performance of injection molded products. However, for the sealing ring for nail guns, it relies on the fusion of two materials at the interface. Under the action of long-term high frequency and high pressure, the interface will peel or crack, resulting in a decrease in sealing performance and a limited overall service life.

[0004] Therefore, for the sealing ring for nail gun, a new injection molding method is needed to improve the sealing performance and durability. Summary of the invention

[0005] The purpose of the present invention is to provide an injection molding method for a sealing ring for a nail gun, so as to solve the problem that the sealing ring for a nail gun produced by the injection molding technology in the prior art has insufficient sealing performance and poor durability.

[0006] To achieve this object, the present invention adopts the following technical solutions: A method for injection molding a sealing ring for a nail gun, comprising: Step S100, injecting a first thermoplastic raw material into a first mold, and obtaining a sealing outer ring member by injection molding; a convex portion is formed on the inner ring surface of the sealing outer ring member; Step S200, applying adhesive to the raised portion, processing the rubber raw material by melt spinning to obtain rubber fiber filaments, and attaching the rubber fiber filaments to the raised portion along the circumferential direction of the sealing outer ring; the rubber fiber filaments are arranged on the raised portion at intervals along the axial direction of the sealing outer ring; Step S300, filling metal powder between two adjacent rubber fiber filaments to form a metal layer; Step S400, placing the sealing outer ring component into the second mold and injecting the second thermoplastic raw material, injection molding the raised portion to obtain the sealing inner ring component, and the sealing outer ring component and the sealing inner ring component are connected to form a sealing ring for a nail gun.

[0007] Optionally, the step S200 includes: Step S210, heating the rubber raw material to a melting temperature to form a uniform molten rubber; Step S220, feeding the molten rubber into a melt spinning device, and continuously extruding the molten rubber on the first surface of the protrusion through a spinning plate provided with a plurality of fine holes, and during the continuous extrusion process of the spinning plate, the spinning plate rotates in a circumferential direction to obtain rubber fiber filaments attached to the first surface; Step S230, turning over the sealing outer ring member, and continuously extruding the rubber fiber filaments on the second surface of the raised portion through a drawing plate provided with a plurality of fine holes, and during the continuous extrusion process of the drawing plate, the drawing plate rotates in a circumferential direction to obtain rubber fiber filaments attached to the second surface; The spacing between the plurality of fine channels matches the spacing between the plurality of rubber fiber filaments.

[0008] Optionally, before step S220, the step further includes: Step S211, preheating the sealing outer ring to a preheating temperature, wherein the preheating temperature is lower than the extrusion temperature of the molten rubber; Step S212, thermally spraying the adhesive uniformly on the surface of the protrusion, wherein the thermal spraying temperature is higher than the preheating temperature and lower than the extrusion temperature of the molten rubber; After step S230, the method further includes: Step S240, hot air baking the sealing outer ring component to adhere the rubber fiber filaments to the sealing outer ring component; Step S250, cooling the sealing outer ring and the rubber fiber filaments.

[0009] Optionally, the step S250 specifically includes: Step S251, placing the sealed outer ring component on a vibration cooling device and performing vibration cooling, while spraying cooling air on the surface of the sealed outer ring component, and the temperature of the cooling air is set to 20-30°C.

[0010] Optionally, the spacing density of the rubber fiber filaments increases gradually along the direction approaching the axis of the sealing outer ring.

[0011] Optionally, the step S300 includes: Step S310, placing a sealing outer ring member having rubber fiber threads attached to both the first surface and the second surface with the first surface facing upward, and spraying metal powder between two adjacent rubber fiber threads to form a first metal part; Step S320, covering the first surface with a protective bracket, wherein the protective bracket covers the first metal part; Step S330: Place the sealing outer ring member with rubber fiber threads attached to both the first surface and the second surface, with the second surface facing upward, and spray metal powder between two adjacent rubber fiber threads to form a second metal part.

[0012] Optionally, the process of spraying the metal powder between two adjacent rubber fiber filaments further includes: Apply low-frequency vibration to the sealing outer ring, and the frequency range of the low-frequency vibration is 20-50Hz; After step S310, the method further includes: Step S311, heating the first metal part and compacting the first metal part; After step S330, the method further includes: Step S331 , heating the second metal part and compacting the second metal part.

[0013] Optionally, the step S400 includes: Step S410, placing the sealing outer ring member with rubber fiber threads attached to both the first and second surfaces into a second mold with the second surface facing upward; the second mold is provided with an insert matching the contour of the protection bracket, and the protection bracket is sleeved outside the insert; Step S420, injecting a second thermoplastic material into the second mold to form a second inner ring portion on one side of the second surface of the protruding portion; Step S430, after removing the insert and the protective bracket, place the sealing outer ring member having rubber fiber threads attached to both the first surface and the second surface, and place it into the second mold with the first surface facing upward; Step S440: injecting a first thermoplastic material into the second mold to form a first inner ring portion on one side of the first surface of the protrusion.

[0014] Optionally, before step S440, the method further includes: Step S431, forming a micro-dimpled structure on the surface of the second inner ring portion; Step S432, depositing a polyurethane coating containing epoxy groups on the surface of the second inner ring portion, and spraying cooling air on the surface of the second inner ring portion at the same time, wherein the temperature of the cooling air is set to 20-30°C.

[0015] Optionally, a concave-convex structure is formed on the surface of the insert facing the second inner ring portion.

[0016] Compared with the prior art, the present invention has the following beneficial effects: The injection molding method of the sealing ring for a nail gun provided by the present invention is to set a protrusion between the sealing outer ring and the sealing inner ring, and arrange rubber fiber filaments at intervals on the protrusion along the circumferential direction of the sealing outer ring. Since the rubber fiber filaments have elasticity and flexibility, they can be deformed appropriately to fill the tiny gaps existing when under pressure, thereby providing a better sealing effect; at the same time, metal powder is filled between the rubber fiber filaments, which effectively improves the internal density and has little effect on the deformation of the rubber fiber filaments, which not only prevents the diffusion of high-pressure gas or liquid inside the sealing ring, but also is not easy to affect the rubber fiber filaments to fill the gaps, thereby improving the overall sealing performance. In addition, the rubber fiber filaments are arranged at intervals, which plays a buffering role when the nail gun is running, making the sealing ring more elastic during repeated extrusion, and not prone to local fatigue damage, thereby improving durability. Therefore, the injection molding method of the sealing ring for a nail gun can effectively improve the sealing performance and service life of the sealing ring for a nail gun. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0018] The structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification so as to facilitate understanding and reading by persons familiar with this technology. They are not used to limit the conditions under which the present invention can be implemented, and therefore have no substantive technical significance. Any structural modification, change in proportion or adjustment of size should still fall within the scope of the technical contents disclosed in the present invention without affecting the effects and purposes that can be achieved by the present invention.

[0019] Figure 1 A schematic flow chart of an injection molding method for a sealing ring for a nail gun provided in an embodiment of the present invention; Figure 2 is a schematic cross-sectional structure diagram of a sealing ring for a nail gun in an embodiment of the present invention; 100, sealing outer ring; 101, raised portion; 1011, first surface; 1012, second surface; 200, rubber fiber filament; 300, metal layer; 310, first metal portion; 320, second metal portion; 400, sealing inner ring; 410, first inner ring portion; 420, second inner ring portion. DETAILED DESCRIPTION

[0020] In order to make the purpose, features and advantages of the present invention more obvious and easy to understand, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described below are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0021] In the description of the present invention, it should be understood that the terms "upper", "lower", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. It should be noted that when a component is considered to be "connected" to another component, it may be directly connected to the other component or there may be a centrally arranged component at the same time.

[0022] The technical solution of the present invention is further described below with reference to the accompanying drawings and through specific implementation methods.

[0023] Embodiment 1: An embodiment of the present invention provides an injection molding method for a sealing ring for a nail gun. The injection molding method is suitable for producing sealing rings in high-frequency and high-pressure scenarios, and is particularly suitable for sealing rings for nail guns. The injection molding method can be applied to an injection molding device for sealing rings for nail guns. In this embodiment, the injection molding method is optimized so that the produced sealing ring for a nail gun has the advantages of strong sealing and high durability.

[0024] like Figure 1 As shown, the injection molding method of the sealing ring for the nail gun in this embodiment includes: Step S100, injecting a first thermoplastic raw material into a first mold, and obtaining a sealing outer ring member 100 by injection molding; a convex portion 101 is formed on the inner ring surface of the sealing outer ring member 100; Step S200, applying adhesive to the raised portion 101, processing the rubber raw material by melt spinning to obtain rubber fiber filaments 200, and attaching the rubber fiber filaments 200 to the raised portion 101 along the circumferential direction of the sealing outer ring 100; the rubber fiber filaments 200 are arranged on the raised portion 101 at intervals along the axial direction of the sealing outer ring 100; Step S300, filling metal powder between two adjacent rubber fiber filaments 200 to form a metal layer 300; Step S400, placing the sealing outer ring 100 into a second mold and injecting a second thermoplastic raw material, injection molding the raised portion 101 to obtain the sealing inner ring 400, and the sealing outer ring 100 and the sealing inner ring 400 are connected to form a sealing ring for a nail gun.

[0025] The first thermoplastic raw material is injected into the first mold, and the sealing outer ring 100 is obtained by injection molding. A protrusion 101 is formed on the inner ring surface of the sealing outer ring 100; the protrusion 101 increases the bonding area between the sealing outer ring 100 and the sealing inner ring 400, thereby improving the sealing performance. Next, a rubber fiber filament 200 and a metal layer 300 are arranged on the protrusion 101. The filling and spacing of the rubber fiber filament 200 can fill the tiny gap and improve the sealing performance; secondly, the filling of the metal powder enhances the internal density of the sealing ring for the nail gun and improves the high pressure resistance.

[0026] Specifically, this embodiment provides a raised portion 101 between the sealing outer ring 100 and the sealing inner ring 400, and arranges rubber fiber filaments 200 at intervals on the raised portion 101 along the circumferential direction of the sealing outer ring 100. Since the rubber fiber filaments 200 are elastic and flexible, they can be deformed appropriately to fill the tiny gaps that exist when under pressure, thereby providing a better sealing effect; at the same time, metal powder is filled between the rubber fiber filaments 200, which effectively increases the internal density and has little effect on the deformation of the rubber fiber filaments 200, which not only prevents the diffusion of high-pressure gas or liquid inside the sealing ring, but also does not easily affect the rubber fiber filaments 200 filling the gaps, thereby improving the overall sealing performance. In addition, the rubber fiber filaments 200 are arranged at intervals, which play a buffering role when the nail gun is running, making the sealing ring more elastic during repeated extrusion, less prone to local fatigue damage, and thus improving durability. Therefore, the injection molding method of the sealing ring for the nail gun can effectively improve the sealing performance and service life of the sealing ring for the nail gun.

[0027] Exemplarily, the first thermoplastic raw material can be thermoplastic polyurethane, and the second thermoplastic raw material can be polyamide. In the high-frequency and high-pressure working environment of the nail gun, thermoplastic polyurethane has excellent elasticity, wear resistance and chemical stability, and is suitable for the application of sealing rings with high elasticity and buffering effects; polyamide has good high temperature resistance, wear resistance and mechanical strength as the sealing inner ring 400, which can enhance the overall stability of the sealing ring for the nail gun.

[0028] Further, step S200 includes: Step S210, heating the rubber raw material to a melting temperature to form a uniform molten rubber; The rubber raw material is heated to the melting temperature to form a uniform molten rubber. The temperature of the molten rubber is controlled within an appropriate range to ensure that the rubber molecular chain will not be degraded due to excessive heating, while maintaining good fluidity to facilitate the subsequent spinning process.

[0029] Step S220, feeding the molten rubber into a melt spinning device, and continuously extruding the molten rubber on the first surface 1011 of the protrusion 101 through a spinning plate provided with a plurality of fine holes. During the continuous extrusion process of the spinning plate, the spinning plate rotates in a circumferential direction to obtain rubber fiber filaments 200 attached to the first surface 1011; wherein the melt spinning device is well known to those skilled in the art, and will not be specifically expanded in this embodiment, and is used to heat the raw material and generate a filamentary or tubular workpiece in the form of spinning, and in this embodiment, the focus is on generating the rubber fiber filaments 200; The molten rubber is fed into the melt spinning device and continuously extruded through a spinning plate provided with a plurality of fine holes; the diameter and spacing of the fine holes of the spinning plate should match the size and sealing requirements of the sealing ring, so that the spacing between the plurality of fine holes matches the spacing between the plurality of rubber fiber filaments 200. In addition, the spinning plate rotates in the circumferential direction while extruding the rubber fiber filaments 200, so that the rubber fiber filaments 200 are evenly attached to the first surface 1011 of the raised portion 101, ensuring that the rubber fiber filaments 200 are arranged closely and evenly, avoiding the problem of poor local sealing.

[0030] Step S230, turning over the sealing outer ring 100, and continuously extruding the rubber fiber filaments 200 on the second surface 1012 of the raised portion 101 through a drawing plate provided with a plurality of fine holes. During the continuous extrusion process, the drawing plate rotates in a circumferential direction to obtain rubber fiber filaments 200 attached to the second surface 1012; In step S230, in order to ensure that the sealing ring is subjected to balanced force during operation and improve the overall sealing performance, the sealing outer ring 100 is turned over, and through a similar melt-drawing process, rubber fiber filaments 200 are also attached to the second surface 1012 of the raised portion 101. By evenly attaching the rubber fiber filaments 200 to the first surface 1011 and the second surface 1012, the sealing ring for the nail gun can distribute stress more evenly when under pressure, while enhancing the sealing performance.

[0031] As a preferred embodiment, the spacing density of the rubber fiber filaments 200 increases along the direction close to the axis of the sealing outer ring 100. It is understandable that when the sealing ring for a nail gun is under pressure, the density of the rubber fiber filaments 200 changes, so that the sealing part can better adapt to and fill the tiny gaps in different stress areas, ensuring that the sealing effect under high pressure will not leak due to the expansion of the gap. Specifically, as the pressure on the sealing outer ring 100 increases, the part close to the outer ring is under greater pressure, while the central part is lighter; by increasing the spacing density of the rubber fiber filaments 200, the nail gun sealing ring can evenly distribute stress under the action of external pressure, avoiding fatigue or wear of local areas due to excessive pressure, thereby increasing the service life of the nail gun sealing ring.

[0032] Based on the above implementation, before step S220, the following steps are further included: Step S211, preheating the sealing outer ring 100 to a preheating temperature, which is lower than the extrusion temperature of the molten rubber; the sealing outer ring 100 needs to be preheated before the rubber fiber filament 200 is attached to ensure that the surface temperature of the sealing outer ring 100 matches the subsequent spraying temperature of the adhesive, thereby improving the adhesion effect of the adhesive.

[0033] Step S212, thermally spray the adhesive uniformly on the surface of the raised portion 101, the thermal spraying temperature is higher than the preheating temperature and lower than the extrusion temperature of the molten rubber; thermal spraying is used to ensure that it is evenly distributed on the surface of the raised portion 101 and has good fluidity under high temperature conditions, so that it can fully penetrate into the tiny gaps.

[0034] After step S230, the method further includes: Step S240, hot air baking the sealing outer ring 100 to adhere the rubber fiber filaments 200 to the sealing outer ring 100; the hot air baking temperature should be controlled at 150°C to 180°C and last for 5-10 seconds, combined with the extrusion temperature of the rubber fiber filaments 200, to ensure that the adhesive is cured in a shorter time and the rubber fiber filaments 200 can be firmly adhered to the surface of the sealing outer ring 100.

[0035] Step S250 , cooling the sealing outer ring 100 and the rubber fiber filaments 200 .

[0036] Among them, the adhesive is a hot-melt polyurethane adhesive, the preheating temperature is 170°C~175°C, the extrusion temperature is 220°C~225°C, the thermal spraying temperature is 190°C~195°C, and the hot air baking temperature is 150°C~180°C.

[0037] It is understandable that the hot melt polyurethane adhesive is selected to form a uniform coating between the rubber fiber filament 200 and the surface of the protrusion 101 by utilizing its fluidity at high temperature; at the same time, the hot melt polyurethane can provide strong adhesion under high temperature conditions and can be well combined with high temperature molten rubber at similar working temperatures.

[0038] Further, step S250 specifically includes: Step S251, placing the sealed outer ring component on a vibration cooling device and performing vibration cooling, while spraying cooling air on the surface of the sealed outer ring component, and the temperature of the cooling air is set to 20-30°C.

[0039] Among them, the vibration cooling equipment uses a vibration table, an ultrasonic vibration device or a vibration cooling fixture, and selects the appropriate vibration frequency and vibration amplitude according to the shape of the sealing outer ring 100. The vibration frequency is set to 20-50Hz, and the vibration amplitude is set to 1-5mm. The sealing outer ring 100 is placed on the vibration cooling equipment, and the equipment is started for vibration cooling. The vibration time is controlled between 5-10 seconds to ensure that the vibration can act evenly on the surface of the raised portion 101 of the sealing outer ring 100, so that the adhesive is evenly distributed during the cooling process. During the vibration process, cooling air is sprayed on the surface of the sealing outer ring 100 through a cooling airflow or a spray cooling system. The cooling air temperature is set to 20-30°C to accelerate the cooling process of the adhesive and prevent surface stress concentration caused by excessive cooling.

[0040] It is understandable that vibration can effectively break the bubbles or uneven cooling bands that may exist in the adhesive, promote the uniform distribution and rapid solidification of the adhesive, and promote the close bonding between the adhesive molecules at the microscopic level, thereby improving the adhesion. By controlling the cooling rate, the surface stress concentration caused by too fast cooling can be avoided, thereby avoiding the problem of cracking on the adhesive surface or interlayer separation. In other words, the vibration process accelerates the uniform solidification of the adhesive, so that any uneven problems in the solidification process are effectively solved. The adhesion and high temperature resistance of the adhesive are enhanced, and finally the overall quality of the nail gun seal is improved.

[0041] Further, step S300 includes: Step S310, the sealing outer ring 100 with rubber fiber filaments 200 attached to both the first surface 1011 and the second surface 1012 is arranged with the first surface 1011 facing upward, and metal powder is sprayed between two adjacent rubber fiber filaments 200 to form a first metal part 310; wherein the metal powder can be aluminum powder, copper powder or stainless steel powder, which has good thermal conductivity and strength, can provide additional support in a high temperature and high pressure environment, and enhance the structural stability and high pressure resistance of the sealing ring for the nail gun; Step S320, covering the first surface 1011 with a protective bracket, wherein the protective bracket covers the first metal part 310; Step S330 , the sealing outer ring 100 having the rubber fiber filaments 200 attached to both the first surface 1011 and the second surface 1012 is arranged with the second surface 1012 facing upward, and metal powder is sprayed between two adjacent rubber fiber filaments 200 to form a second metal part 320 .

[0042] It is understandable that after the filling of the first metal part 310 is completed, a protective bracket is then covered on the first surface 1011 to prevent the metal powder from loosening or shifting in the subsequent process, especially to prevent the metal powder from falling due to instability. Then, the sealing outer ring 100 is turned over so that the second surface 1012 faces upward, and the metal powder is sprayed again to fill between the two adjacent rubber fiber filaments 200 to form the second metal part 320; this process also uses a spraying process similar to step S310 to ensure that the metal powder is evenly filled between the two rubber fiber filaments 200 to form a complete metal layer 300. Through the above steps, the uniform spraying and filling of the metal powder is guaranteed, thereby ensuring the compactness of the metal layer 300, effectively improving the mechanical strength of the sealing ring, preventing the risk of gas or liquid leakage, and providing the sealing ring with additional pressure resistance and wear resistance.

[0043] As a supplementary embodiment, the process of spraying the metal powder between two adjacent rubber fiber filaments 200 further includes: Apply low-frequency vibration to the sealing outer ring 100, and the frequency range of the low-frequency vibration is 20-50Hz; the low-frequency vibration helps to break the aggregation phenomenon in the metal powder, so that the metal powder can be more evenly filled into the tiny gaps between the rubber fiber filaments 200. This not only improves the filling density, but also reduces the problem of structural instability or reduced sealing performance caused by uneven filling; After step S310, the method further includes: Step S311, heating the first metal part 310 and compacting the first metal part 310; After step S330, the method further includes: Step S331, heat the second metal part 320, and compact the second metal part 320. The heating temperature in step S311 and step S330 is not higher than the melting temperature of the metal powder, which promotes the uniform distribution of the metal powder. It can be understood that the subsequent heating and compaction treatments work together to avoid the accumulation or uneven distribution of the metal powder, thereby improving the overall strength and structural stability of the metal layer 300, making the metal layer 300 equivalent to the flexible filling of the gap between the rubber fiber filaments 200, improving the overall density of the sealing ring for the nail gun, not affecting the deformation of the rubber fiber filaments 200, and effectively preventing gas or liquid leakage, thereby improving the sealing effect of the sealing ring.

[0044] Further, step S400 includes: Step S410, the sealing outer ring 100 with the rubber fiber filaments 200 attached to the first surface 1011 and the second surface 1012 is placed into a second mold with the second surface 1012 facing upward; the second mold is provided with an insert matching the contour of the protection bracket, and the protection bracket is sleeved outside the insert; Step S420, injecting a second thermoplastic material into the second mold to form a second inner ring portion 420 on one side of the second surface 1012 of the protruding portion 101; Step S430, after removing the insert and the protective bracket, the sealing outer ring 100 with the rubber fiber filaments 200 attached to both the first surface 1011 and the second surface 1012 is placed into the second mold with the first surface 1011 facing upward; Step S440 , injecting a first thermoplastic material into the second mold to form a first inner ring portion 410 on one side of the first surface 1011 of the protruding portion 101 .

[0045] First, place the sealing outer ring 100 to which the rubber fiber filament 200 has been attached into the second mold, and place it in a manner that the second surface 1012 faces upward. At this time, an insert matching the contour of the protective bracket is provided in the second mold, and the protective bracket is sleeved outside the insert. The insert, on the one hand, ensures that the protective bracket remains stable during the injection molding process, and avoids displacement or deformation of the sealing outer ring 100 during the subsequent injection molding process, and also prevents the metal powder corresponding to the first surface 1011 from falling. Next, the sealing outer ring 100 after the protective bracket is removed is placed back into the second mold, and the first surface 1011 is placed upward at this time. Next, a second thermoplastic raw material is injected into the second mold to form a first inner ring portion 410 on one side of the first surface 1011 of the raised portion 101. Through this step, the connection between the sealing outer ring 100 and the sealing inner ring 400 is finally completed, ensuring the structural integrity and sealing of the sealing ring for the nail gun.

[0046] Based on the above implementation, before step S440, the method further includes: Step S431, forming a micro-dimpled structure on the surface of the second inner ring portion 420; forming the micro-dimpled structure on the surface of the second inner ring portion 420 helps to provide more surface area and enhance the contact and adhesion between the second inner ring portion 420 and the first inner ring portion 410. The micro-dimpled structure increases the surface roughness, so that the contact between the two inner ring portions is closer, thereby enhancing their connection and preventing peeling or delamination during use; wherein the formation of the micro-dimpled structure can be achieved by corrosion, laser micro-engraving, etc.; Step S432: depositing a polyurethane coating containing epoxy groups on the surface of the second inner ring portion 420, and spraying cooling air on the surface of the second inner ring portion 420, with the temperature of the cooling air set to 20-30° C. The epoxy groups can form strong chemical bonds with the surface of the second inner ring portion 420 and the surface of the first inner ring portion 410, ensuring a stronger connection between the inner ring portions.

[0047] A concavo-convex structure is formed on the surface of the insert facing the second inner ring portion 420. The concavo-convex structure is formed on the surface of the insert facing the second inner ring portion, further enhancing the surface roughness of the second inner ring portion 420. This concavo-convex structure helps to form a more secure mechanical connection between the inner ring portions, prevents coating peeling or internal failure, and thus improves the overall bonding force between the first inner ring portion 410 and the second inner ring portion 420.

[0048] Embodiment 2: This embodiment also provides an injection molding device for a sealing ring for a nail gun, which adopts the injection molding method in the first embodiment, and at least includes a first mold and a second mold, wherein the first mold is used to mold the sealing outer ring 100, and the second mold is used to mold the sealing inner ring 400 on the sealing outer ring 100. Regarding the installation of the rubber fiber filament 200, in addition to the melt drawing scheme, the rubber fiber filament 200 can also be purchased and then attached by a robot; regarding the spraying of the metal powder, in addition to the spraying scheme, a scheme similar to manual brushing of the metal powder can also be used. In this injection molding device, the focus is on molding the sealing outer ring 100 through the first mold, and then setting the rubber fiber filament 200 and the metal layer 300 before the secondary injection molding of the sealing outer ring 100, and then secondary injection molding the sealing outer ring 100 to obtain the sealing ring for the nail gun.

[0049] As described above, the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for injection molding a sealing ring for a nail gun, characterized in that: include: Step S100, injecting a first thermoplastic raw material into a first mold of an injection molding device, and injection molding to obtain a sealing outer ring component; A convex portion is formed on the inner ring surface of the sealing outer ring; Step S200, applying adhesive to the raised portion, processing the rubber raw material by melt spinning to obtain rubber fiber filaments, and attaching the rubber fiber filaments to the raised portion along the circumferential direction of the sealing outer ring; the rubber fiber filaments are arranged on the raised portion at intervals along the axial direction of the sealing outer ring; Step S300, filling metal powder between two adjacent rubber fiber filaments to form a metal layer; Step S400, placing the sealing outer ring component into the second mold of the injection molding device and injecting the second thermoplastic raw material, injection molding the sealing inner ring component on the protrusion, and connecting the sealing outer ring component with the sealing inner ring component to form a sealing ring for a nail gun.

2. The method for injection molding a sealing ring for a nail gun according to claim 1, characterized in that: The step S200 includes: Step S210, heating the rubber raw material to a melting temperature to form a uniform molten rubber; Step S220, feeding the molten rubber into a melt spinning device, and continuously extruding the molten rubber on the first surface of the protrusion through a spinning plate provided with a plurality of fine holes, and during the continuous extrusion process of the spinning plate, the spinning plate rotates in a circumferential direction to obtain rubber fiber filaments attached to the first surface; Step S230, turning over the sealing outer ring member, and continuously extruding the rubber fiber filaments on the second surface of the raised portion through a drawing plate provided with a plurality of fine holes, and during the continuous extrusion process of the drawing plate, the drawing plate rotates in a circumferential direction to obtain rubber fiber filaments attached to the second surface; The spacing between the plurality of fine channels matches the spacing between the plurality of rubber fiber filaments.

3. The method for injection molding a sealing ring for a nail gun according to claim 2, characterized in that: Before step S220, the following steps are also included: Step S211, preheating the sealing outer ring to a preheating temperature, wherein the preheating temperature is lower than the extrusion temperature of the molten rubber; Step S212, thermally spraying the adhesive uniformly on the surface of the protrusion, wherein the thermal spraying temperature is higher than the preheating temperature and lower than the extrusion temperature of the molten rubber; After step S230, the method further includes: Step S240, hot air baking the sealing outer ring component to adhere the rubber fiber filaments to the sealing outer ring component; Step S250, cooling the sealing outer ring and the rubber fiber filaments; Wherein, the adhesive is a hot-melt polyurethane adhesive.

4. The method for injection molding a sealing ring for a nail gun according to claim 3, characterized in that: The step S250 specifically includes: Step S251, placing the sealed outer ring component on a vibration cooling device and performing vibration cooling, while spraying cooling air on the surface of the sealed outer ring component, and the temperature of the cooling air is set to 20-30°C.

5. The method for injection molding a sealing ring for a nail gun according to claim 3, characterized in that: Along the direction approaching the axis of the sealing outer ring, the spacing density of the rubber fiber filaments increases.

6. The method for injection molding a sealing ring for a nail gun according to claim 2, characterized in that: The step S300 includes: Step S310, placing a sealing outer ring member having rubber fiber threads attached to both the first surface and the second surface with the first surface facing upward, and spraying metal powder between two adjacent rubber fiber threads to form a first metal part; Step S320, covering the first surface with a protective bracket, wherein the protective bracket covers the first metal part; Step S330: Place the sealing outer ring member with rubber fiber threads attached to both the first surface and the second surface, with the second surface facing upward, and spray metal powder between two adjacent rubber fiber threads to form a second metal part.

7. The method for injection molding a sealing ring for a nail gun according to claim 6, characterized in that: The process of spraying the metal powder between two adjacent rubber fiber filaments also includes: Apply low-frequency vibration to the sealing outer ring, and the frequency range of the low-frequency vibration is 20-50Hz; After step S310, the method further includes: Step S311, heating the first metal part and compacting the first metal part; After step S330, the method further includes: Step S331 , heating the second metal part and compacting the second metal part.

8. The method for injection molding a sealing ring for a nail gun according to claim 6, characterized in that: The step S400 includes: Step S410, placing the sealing outer ring member with rubber fiber threads attached to both the first and second surfaces into a second mold with the second surface facing upward; the second mold is provided with an insert matching the contour of the protection bracket, and the protection bracket is sleeved outside the insert; Step S420, injecting a second thermoplastic material into the second mold to form a second inner ring portion on one side of the second surface of the protruding portion; Step S430, after removing the insert and the protective bracket, place the sealing outer ring member having rubber fiber threads attached to both the first surface and the second surface, and place it into the second mold with the first surface facing upward; Step S440: injecting a first thermoplastic material into the second mold to form a first inner ring portion on one side of the first surface of the protrusion.

9. The method for injection molding a sealing ring for a nail gun according to claim 8, characterized in that: Before step S440, the method further includes: Step S431, forming a micro-dimpled structure on the surface of the second inner ring portion; Step S432, depositing a polyurethane coating containing epoxy groups on the surface of the second inner ring portion, and spraying cooling air on the surface of the second inner ring portion at the same time, wherein the temperature of the cooling air is set to 20-30°C.

10. The method for injection molding a sealing ring for a nail gun according to claim 8, characterized in that: A concave-convex structure is formed on the surface of the insert facing the second inner ring portion.

Images