CN114474568A

CN114474568A - Conductive foam injection molding device and conductive foam injection molding process

Info

Publication number: CN114474568A
Application number: CN202210062642.9A
Authority: CN
Inventors: 张海兴; 孙爱祥; 窦兰月; 周晓燕
Original assignee: Shenzhen Hongfucheng New Material Co ltd
Current assignee: Shenzhen Hongfucheng New Material Co ltd
Priority date: 2022-01-19
Filing date: 2022-01-19
Publication date: 2022-05-13
Anticipated expiration: 2042-01-19
Also published as: CN114474568B

Abstract

The application relates to a cotton injection molding device of electrically conductive bubble and cotton injection molding technology of electrically conductive bubble relates to the cotton field of electrically conductive bubble. The conductive foam injection molding device comprises a feeding mechanism, an injection molding mechanism and a receiving mechanism which are sequentially arranged along the advancing direction of the conductive film; the injection molding mechanism comprises a conductive film molding assembly and a colloid injection molding assembly which are sequentially arranged along the advancing direction of the conductive film; the conductive film forming assembly is used for rolling and forming the conductive film; the colloid injection molding assembly is used for injecting colloid into the conductive film coating inner cavity and curing the colloid. Compared with the traditional preparation method of coating the conductive film on the prefabricated core strip, the preparation method of the conductive foam has the advantages that the conductive foam is prepared in an injection molding mode, and the colloid has a better filling effect in the coating inner cavity, so that the appearance of the product can be obviously improved, and the poor contact caused by the appearance structure problem can be further improved; in addition, the core strip and the conducting film have wide selectivity and can be produced in more modes.

Description

Conductive foam injection molding device and conductive foam injection molding process

Technical Field

The application relates to the field of conductive foam, in particular to a conductive foam injection molding device and a conductive foam injection molding process.

Background

The conductive foam is a conductive electronic shielding material, the main material of the conductive foam is a sponge core strip which is formed by extruding polyethylene or modified polyethylene, conductive filler and antistatic agent, then performing radiation crosslinking and high-temperature foaming, and then wrapping a layer of conductive cloth adhesive tape around the core strip by processing, so that the conductive foam has shielding performance and conductive performance. The SMT conductive foam is a conductive contact terminal which can be reflow-welded on a PCB board by an SMT technology and has excellent elasticity, is one of conductive foams and is used for EMI (electro-magnetic interference), grounding or conductive terminals, and a core strip of the SMT conductive foam can be made of materials such as silica gel and the like.

The SMT foam production commonly used at present mostly adopts the core strip of extrusion moulding in advance, then coats the conducting film shaping again through coating glue, adheres the conducting film on the core strip through glue. Because the core strip is made of a material with elastic compression performance, when the conductive foam is prepared by the method, the problem that the conductive film is not sufficient for coating is very easy to occur, and the core strip is very easy to pull in the coating forming process, so that the two ends of the cut product are recessed and retracted, the contact surface of the conductive film is reduced, and the product performance is influenced; meanwhile, the glue coating process in the preparation process is complicated and not easy to clean, and the production efficiency and the product quality are seriously influenced.

Disclosure of Invention

In order to promote the filling nature of conducting film cladding on the core strip, further promote the cotton performance of electrically conductive bubble and improve production efficiency, this application provides a cotton injection moulding device of electrically conductive bubble and cotton injection moulding technology of electrically conductive bubble.

In a first aspect, the present application provides a conductive foam injection molding device, which adopts the following technical scheme:

a conductive foam injection molding device comprises a feeding mechanism, an injection molding mechanism and a material receiving mechanism which are sequentially arranged along the advancing direction of a conductive film; the injection molding mechanism comprises a conductive film molding assembly and a colloid injection molding assembly which are sequentially arranged along the advancing direction of the conductive film; the conductive film forming assembly is used for rolling and forming a conductive film to obtain a conductive film coating cavity; the colloid injection molding assembly is used for injecting colloid into the conductive film coating inner cavity and curing the colloid.

By adopting the technical scheme, the conducting film is conveyed to the injection molding mechanism by the feeding mechanism, the conducting film is rolled and molded by the conducting film molding assembly to obtain the conducting film coating cavity, and then the liquid colloid is injected and filled into the rolled and molded conducting film coating cavity by the colloid injection molding assembly and is cured and molded. The conducting film passes through the in-process that receiving agencies drove and continuously move forward, and the colloid is injected in succession and is filled the conducting film cladding chamber, forms the cotton core strip of conducting bubble after the colloid solidification, and the core strip forms stable in structure's conducting bubble cotton together with the conducting film through the viscidity adhesion of colloid self. The cotton injection moulding device of electrically conductive bubble that this application technical scheme provided adopts colloid injection moulding mode, compares in traditional core cladding conductive film, and the electrically conductive bubble that makes is cotton has better abundant effect, can obviously improve the outward appearance of product, also can improve the contact failure because of the outward appearance structural problem brings simultaneously.

Optionally, the conductive film forming assembly includes a forming base, and a cavity with a U-shaped longitudinal section is horizontally formed in the forming base in a penetrating manner; and a mold core matched with the mold cavity is fixed on the molding base.

By adopting the technical scheme, the conducting film is led out from the feeding mechanism and then penetrates into the cavity on the forming base, the width of the cavity is designed to be smaller than that of the conducting film, on the basis, two sides of the conducting film can be upwards turned over through the matching of the cavity and the core, the conducting film is rolled into a U shape to form a conducting film coating cavity, and the conducting film is filled with colloid later.

Optionally, the cavity includes a feeding section, a necking section and a discharging section, which are continuously arranged along the advancing direction of the conductive film, and the width of the necking section is gradually reduced along the advancing direction of the conductive film.

By adopting the technical scheme, in the advancing process of the conductive film in the cavity, when the conductive film passes through the necking section, because the width of the necking section is gradually reduced, two sides of the conductive film are forced to be upwards folded and rolled to form the U-shaped conductive film coating cavity.

Optionally, the colloid molding assembly comprises a heating base and a glue injection needle cylinder fixed on the heating base, an electric heater is mounted on the heating base, and a temperature control sensor and a control system are matched with the electric heater; a material passing channel penetrates through the heating base along the advancing direction of the conductive film, and the top of the material passing channel is provided with a glue injection port communicated with a glue outlet of the glue injection needle cylinder; an inner core needle is detachably connected to the heating base and is located in the material passing channel.

By adopting the technical scheme, the conductive film enters the material passing channel on the heating base from the cavity on the forming base, the colloid is injected into the conductive film coating cavity through the glue injection needle cylinder, and the colloid is heated and cured in the heating base to form the core strip of the conductive foam in the process that the conductive film continuously advances. Because the inner core needle is arranged in the material passing channel, the inner core needle can be coated in the colloid injection process, and after colloid curing molding is taken out from the inner core needle, a structural cavity penetrating through the whole core strip in the length direction can be formed inside the colloid core strip, so that the prepared conductive foam has better compressibility.

Optionally, a through hole is formed in the inner core needle in an axially penetrating manner.

Through adopting above-mentioned technical scheme, through the inside compressibility that forms the structure chamber in order to strengthen the core strip of electrically conductive bubble cotton core strip of inner core needle, and break away from the back from inner core needle after the colloid solidification moulding, at the continuous injection moulding's of colloid in-process, the core strip inner chamber forms low pressure environment easily, leads to the core strip compressive deformation. After the through holes are axially arranged on the inner core needle in a penetrating manner, the colloid can continuously convey air to the inner cavity of the core strip in the process of pulling away from the inner core needle, so that the air pressure inside and outside the core strip is kept consistent, and the stability of the whole appearance structure of the conductive foam is ensured.

Optionally, a cold water cavity is further formed in the heating base, the cold water cavity is located below the glue injection needle cylinder, and the cold water cavity is communicated with an external water source.

Through adopting above-mentioned technical scheme, at the in-process of heating base heating curing colloid, the heat that the electric heater produced can conduct to injecting glue cylinder position, and at the in-process of heating for a long time, there is the risk that leads to injecting glue cylinder jam with the colloid solidification of injecting glue cylinder play jiao kou position. Through set up the cold water chamber on heating the base, insert outside cooling water in the cold water chamber, be the cooling of injecting glue cylinder position through the cooling water, avoid the colloid in the injecting glue cylinder to be heated the solidification. The cooling water can be cold water prepared by a cooling machine at 4-15 deg.C or normal temperature tap water.

Optionally, the feeding mechanism comprises a material placing frame, a feeding roller and a limiting roller are arranged on the material placing frame, a fixed-width buckle is arranged on the limiting roller, and the height of the discharging position on the fixed-width buckle is not higher than the height of the feeding hole of the conductive film forming assembly.

By adopting the technical scheme, the conducting film and/or the protective film coated on the outer side of the conducting film are conveyed to the conducting film forming mechanism through the feeding roller and the limiting roller, the feeding position of the conducting film and/or the protective film is limited through the width fixing buckle on the limiting roller, and the conducting film and/or the protective film are prevented from shifting in the feeding process.

Optionally, the receiving mechanism comprises a receiving platform and a traction crawler, and the traction crawler is located between the receiving platform and the injection molding mechanism; the traction caterpillar comprises an upper traction caterpillar and a lower traction caterpillar which rotate in opposite directions, and a gap which is used for the conductive foam to pass through and has adjustable height is reserved between the upper traction caterpillar and the lower traction caterpillar.

Through adopting above-mentioned technical scheme, the cotton back of making the shaping through injection moulding mechanism of electrically conductive bubble, long banding electrically conductive bubble is cotton by last track and the centre gripping of lower track of pulling to along with last track and the rotation of lower track of pulling and remove to receiving the material platform, accomplish follow-up receipts material work on receiving the material platform.

In a second aspect, the present application provides a conductive foam injection molding process, which adopts the following technical scheme:

a conductive foam injection molding process comprises the following steps:

feeding: placing the conductive film in a feeding mechanism, drawing the front end of the conductive film to sequentially pass through a conductive film forming assembly and a colloid injection forming assembly to a receiving mechanism, and rolling and forming the conductive film by the conductive film forming mechanism to obtain a conductive film coating cavity;

injection molding: starting the material receiving mechanism to drive the conductive film to move, and controlling the moving speed to be 0.5-2 m/min; injecting colloid with the viscosity of 80-2000 mPa.s into the conductive film coating cavity through a colloid injection molding assembly, and heating to 60-150 ℃ to solidify and mold the colloid; more preferably, the heating temperature is 120-.

Receiving: and (4) pulling the formed product to a material receiving mechanism, and slitting to obtain a product strip with a specified length.

By adopting the technical scheme, the conductive foam injection molding device is applied, and colloid is filled into the conductive film coating cavity in an injection molding mode to prepare the conductive foam. The conductive film can be a composite polymer film or conductive cloth with a conductive coating; the colloid can be liquid silica gel, silica gel glue or foam cotton. The conductive foam injection molding process provided by the application is matched with the conductive foam injection molding device, so that the production steps of the conductive foam can be effectively simplified, the production efficiency is improved, and the prepared conductive foam has better filling effect and product performance; in addition, the conductive foam injection molding process provided by the application has a wide selection range of conductive films and colloids, and can be applied to production and preparation of conductive foam in various production scenes.

In summary, the present application includes at least one of the following beneficial technical effects:

1. according to the conductive foam injection molding device and the conductive foam injection molding process, the conductive foam is prepared in an injection molding mode, compared with a traditional preparation method for coating a conductive film by a prefabricated core strip, a colloid has a better filling effect in a coating inner cavity, the appearance of a product can be obviously improved, and poor contact caused by the problem of appearance structure is further improved;

2. according to the technical scheme, an integrated molding technology is adopted, and the colloid is directly heated and molded after being injected into the conductive film coating cavity, so that the production process of conductive foam is effectively reduced, the occurrence of poor manufacturing can be effectively reduced, and the comprehensive yield of products is improved;

3. the conductive foam injection molding process provided by the application can be not limited to the core strip and the conductive film with specific structures and materials, has multiple production mode choices, and is wide in application range.

Drawings

Fig. 1 is a schematic overall structure diagram of a conductive foam injection molding device according to an embodiment of the present application.

Fig. 2 is a schematic structural view of the conductive film forming assembly of fig. 1.

Fig. 3 is a schematic structural view of the molded base of fig. 2.

Fig. 4 is a schematic view of the construction of the core of fig. 2.

Fig. 5 is a schematic view of the structure of the gel injection molding assembly of fig. 1.

Fig. 6 is a cross-sectional view of the injection nozzle portion of fig. 5.

Fig. 7 is a cross-sectional view of fig. 5.

Fig. 8 is a schematic view showing the structure of the inner core pin of fig. 5.

Fig. 9 is a schematic structural diagram of the conductive foam provided in application example 1.

Fig. 10 is a schematic mechanism diagram of the conductive foam provided in application example 2.

Fig. 11 is a schematic structural view of the conductive foam provided in application example 3.

Description of reference numerals: 1. a machine base; 2. a feeding mechanism; 21. a material placing frame; 22. a feeding roller; 221. a conductive film feeding roller; 222. a protective film feeding roller; 23. a limiting roller; 231. a conductive film limiting roller; 232. a protective film limiting roller; 24. fixing a width buckle; 3. an injection molding mechanism; 31. a forming table; 32. a conductive film forming assembly; 321. a support base; 322. forming a base; 323. a cavity; 3231. a feeding section; 3232. a necking section; 3233. a discharging section; 324. a core; 33. a gel injection molding assembly; 331. curing the assembly; 3311. heating the base; 33111. left heating mould; 33112. right heating mould; 3312. an electric heater; 3313. a temperature sensor; 3314. a material passing channel; 3315. heating the fixing cover; 3316. sealing a needle strip; 3317. an inner core needle; 33171. a through hole; 3318. an inner core needle fixing seat; 33181. mounting blocks; 33182. a sleeved rod; 3319. a glue injection port; 332. a cold water chamber; 333. a glue injection assembly; 3331. a glue injection needle cylinder; 3332. a glue injection nozzle; 33321. injecting a slit; 4. a material receiving mechanism; 41. a traction caterpillar; 411. an upper traction track; 412. a lower traction track; 42. a material receiving platform; 5. conductive foam; 51. a conductive film; 52. a protective film; 53. a conductive composite film; 531. coating the gap; 54. a silica gel core strip; 541. a half-height structural core; 542. filling a silica gel layer; 543. a full-size core bar; 544. an adhesive layer; 55. a structural cavity.

Detailed Description

The present application is described in further detail below with reference to figures 1-11.

The embodiment of the application discloses cotton injection moulding device of electrically conductive bubble.

Referring to fig. 1, the device for injection molding of the conductive foam includes a base 1, and a feeding mechanism 2, an injection molding mechanism 3, and a receiving mechanism 4 are sequentially disposed on the base 1 along a forward direction of a conductive film 51. Injection moulding mechanism 3 includes moulding platform 31, install conducting film shaping subassembly 32 and colloid injection moulding subassembly 33 on the moulding platform 31, conducting film 51 is from feed mechanism 2 material loading, it forms conducting film cladding chamber to be rolled up the shaping when the conducting film shaping subassembly 32, then through colloid injection moulding subassembly 33 with the colloid of preparing inject the conducting film cladding chamber in and solidification shaping obtains the electrically conductive bubble cotton 5, electrically conductive bubble cotton 5 draws through receiving agencies 4 and continues to remove, and accomplish follow-up cutting and packing operation at receiving agencies 4.

Referring to fig. 1, the feeding mechanism 2 includes a material placing frame 21 vertically fixed on the base 1, a feeding roller 22 and a limiting roller 23 are arranged on the material placing frame 21, and the limiting roller 23 is located below the feeding roller 22. The feeding roller 22 includes a conductive film feeding roller 221 and a protective film feeding roller 222, both rotatably connected to the discharging frame 21. The limiting roller 23 comprises a conductive film limiting roller 231 and a protective film limiting roller 232 which are fixedly connected to the material placing frame 21, the conductive film limiting roller 231 and the protective film limiting roller 232 are respectively connected with a fixed-width buckle 24 in a rotating mode, and the two fixed-width buckles 24 are aligned and horizontally arranged along the advancing direction of the conductive film 51.

Referring to fig. 2 and 3, the conductive film forming assembly 32 includes a supporting base 321 and a forming base 322, the supporting base 321 is fixedly mounted on the forming table 31, and the forming base 322 is fixedly mounted on the supporting base 321. The top of the forming base 322 is provided with a cavity 323 along the horizontal direction, and the longitudinal section of the cavity 323 is U-shaped. The cavity 323 is divided into a continuous feed section 3231, a necking section 3232 and a discharge section 3233 along the advancing direction of the conductive film 51, and the width of the necking section 3232 is gradually reduced along the advancing direction of the conductive film 51. The conductive film 51 enters the cavity 323 from the feeding section 3231, and the two sides of the conductive film 51 are folded upward into a U shape by the pressing action of the two side walls when passing through the necking section 3232. A core 324 which is matched with the cavity 323 is further fixed on the supporting base 321 through bolts, and the core 324 is positioned in the cavity 323 and has a width which does not exceed the width of the discharging section 3233. With reference to fig. 4, after the conductive film 51 passes through the necking section 3232, two sides of the conductive film are folded upwards to obtain a conductive film coating cavity with a U-shaped longitudinal section, then, under the cooperation of the cavity 323 and the core 324, two sides of the conductive film 51 are continuously and horizontally folded inwards, and a coating gap 531 with a certain width is formed between two sides of the conductive film 51 after the conductive film 51 is folded twice for injecting a glue.

The conductive film 51 passes through the conductive film forming assembly 32 and then moves to the glue injection forming assembly 33, referring to fig. 1, the glue injection forming assembly 33 includes a curing assembly 331 and a glue injection assembly 333 mounted on the curing assembly 331, the glue is injected into the conductive film coating cavity through the glue injection assembly 333, and then the glue is cured and formed through the curing assembly 331. Referring to fig. 5 and 6, the glue injection assembly 333 includes a glue injection syringe 3331 and a glue injection nozzle 3332 in threaded connection with the glue injection syringe 3331, the glue injection nozzle 3332 is hollow, the top of the glue injection nozzle 3332 is communicated with a glue outlet of the glue injection syringe 3331, a glue injection slit 33321 is formed in the bottom of the glue injection nozzle 3332, the width of the glue injection slit 33321 is not more than the width of the coating gap 531 at the top of the conductive film coating cavity, and the glue is injected into the conductive film coating cavity from the glue injection slit 33321 through the glue injection nozzle 3332 after being loaded into the glue injection syringe 3331.

Referring to fig. 7 and 8, the curing unit 331 includes a heating base 3311, a left heating mold 33111, and a right heating mold 33112, and an electric heater 3312 and a temperature sensor 3313 are mounted on the heating base 3311. The left heating mold 33111 and the right heating mold 33112 are fixedly mounted on the heating base 3311 by bolts, a material passing channel 3314 for passing the conductive film 51 is reserved between the left heating mold 33111 and the right heating mold 33112, and the material passing channel 3314 is located above the electric heater 3312 and is provided with an opening at the top. The longitudinal section of the material passing channel 3314 has a shape corresponding to the longitudinal section of the conductive film coating cavity formed by the second folding so as to ensure that the conductive film 51 is not deformed when moving in the material passing channel 3314. Still install a fixed lid 3315 of heating at left heating mould 33111 and right heating mould 33112 top, the fixed lid 3315 of heating passes through bolt and left heating mould 33111 and right heating mould 33112 fixed connection, be fixed with on the fixed lid 3315 of heating and seal needle strip 3316, the one end that goes up the needle strip 3316 and be close to the injection subassembly extends to injecting glue slit 33321 position, seal the open-top that material passageway 3314 is located the heating section through last needle strip 3316, avoid the colloid in the conducting film cladding chamber to spill over from the cladding gap at conducting film 51 top.

An inner core needle 3317 is further installed on the heating base 3311, the inner core needle 3317 is located in the material passing channel 3314, an inner core needle fixing base 3318 is fixed to one end of the inner core needle 3317 by a bolt, and the inner core needle fixing base 3318 is fixedly installed on the heating base 3311 by a bolt and located at one end of the heating base 3311 close to the conductive film forming component 32. Referring to fig. 9, the inner core needle fixing base 3318 includes an installation block 33181 and a sleeve rod 33182 which are integrally formed, the installation block 33181 is fixed on the heating base 3311 by a bolt, a sleeve hole matching with the outer shape of the inner core needle 3317 is axially formed on the sleeve rod 33182, and the inner core needle 3317 is fixedly connected to the sleeve rod 33182 by a bolt after being inserted into the sleeve hole. The shape of the socket rod 33182 fits the material passing channel 3314, and a gap for the conductive film 51 to pass through is reserved between the socket rod 33182 and the sidewall of the material passing channel 3314, and the conductive film 51 enters the gap between the material passing channel 3314 and the socket rod 33182 after being output from the conductive film forming assembly 32, so as to keep the shape of the conductive film coating cavity unchanged. Referring to fig. 8, a glue injection port 3319 for injecting glue is defined between the sleeving rod 33182 and the upper needle sealing strip 3316, and the glue injection port 3319 is communicated with the glue injection slit 33321. The conductive film 51 wraps the inner core pin 3317 in the conductive film coating cavity during the movement in the material passing channel 3314, and then the glue is injected into the conductive film coating cavity through the glue injection port 3319. After colloid is injected into the conductive film coating cavity, the conductive film coating cavity continuously moves forwards to pass through the heating base 3311, and the colloid is heated and cured to form a core strip, so that the conductive foam is obtained. Due to the existence of the inner core needle 3317, a structure cavity can be formed inside the core strip after the colloid is solidified, and the compression deformation of the conductive foam 5 is realized through the structure cavity.

In another embodiment, the outside of the core pins 3317 is further coated with a hard coating, which may be a hard teflon or titanium coating, to improve the smoothness of the surface of the core pins 3317, reduce the friction between the glue and the core pins 3317, and facilitate the separation of the glue from the core pins 3317 after the glue is cured.

The through hole 33171 has been seted up along the axial on the inner core needle 3317 through running through, the cotton 5 in-process that moves forward of electrically conductive bubble, continuously inputs the air to the inside structure chamber of core strip through hole 33171 for the atmospheric pressure of the inside and outside side of core strip keeps unanimous, avoids the cotton 5 of electrically conductive bubble to appear warping because of inside atmospheric pressure is lower.

A cold water cavity 332 is further formed in the heating base 3311, the cold water cavity 332 is located right below the glue injection nozzle 3332, and the cold water cavity 332 is connected with an external cooling water source. In the process of colloid injection molding, the position of the glue injection nozzle 3332 is cooled by accessing the circulating cooling water, and the colloid in the glue injection nozzle 3332 is prevented from being heated and solidified to influence the injection of the colloid.

Referring to fig. 1, the material receiving mechanism 4 includes a material receiving platform 42 and a traction crawler 41, and the traction crawler 41 is fixed on the frame 1. The traction caterpillar 41 comprises an upper traction caterpillar 411 and a lower traction caterpillar 412 which rotate in opposite directions, a gap exists between the upper traction caterpillar 411 and the lower traction caterpillar 412, the height of the gap is adjustable, the conductive foam 5 is clamped and driven by the upper traction caterpillar 411 and the lower traction caterpillar 412 to move forwards to the material receiving platform 42, and the conductive foam 5 is subjected to subsequent cutting, packaging and other operations on the material receiving platform 42.

In another embodiment, a cooling channel (not shown) is further disposed between the traction track 41 and the injection molding assembly, and the conductive foam 5 obtained through high-temperature solidification is cooled by the cooling channel and then reaches the material receiving platform 42 for subsequent operation.

According to the conductive foam injection molding device provided by the embodiment of the application, the conductive foam is prepared in an injection molding mode, and compared with a traditional preparation method for coating a conductive film on a prefabricated core strip, a colloid has a better filling effect in a coating inner cavity, the appearance of a product can be obviously improved, and poor contact caused by the problem of an appearance structure is further improved; in addition, according to the technical scheme of injection molding, the core strip is made of various materials selectively, the specification and the size of the conductive foam are selectable, and more production modes can be selected; the colloid is directly heated and formed after being injected into the conductive film coating cavity, so that the production process of the conductive foam is effectively reduced, the occurrence of poor processing can be effectively reduced, and the comprehensive yield of products is improved.

The technical solution of the present application is further described below with reference to specific application examples. The following non-specific ones are all performed under conventional conditions or conditions recommended by the manufacturer; the raw materials used in the following application examples are those available from ordinary commercial sources unless otherwise specified.

The types of some of the raw materials in the following application examples are shown in table 1 below:

table 1: part of raw material sources in application examples

Application example 1

Preparing raw materials: the colloid is liquid silica gel with the viscosity of 1000 mPa.s, a lubricant accounting for 3 percent of the total weight of the liquid silica gel, a flame retardant accounting for 15 percent of the total weight of the liquid silica gel and silica gel color paste accounting for 0.1 percent of the total weight of the liquid silica gel are added into the liquid silica gel, and the mixture is stirred and mixed uniformly; the conductive film 51 is a nickel-plated PI film with the thickness of 15 microns, and the insulating surface of the nickel-plated PI film is subjected to corona treatment, so that the wettability of the insulating surface of the nickel-plated PI film is improved, and the bonding strength between the liquid silica gel and the nickel-plated PI film is enhanced; the protective film is a PET protective film with the thickness of 25 mu m; and (4) coiling and cutting the nickel-plated PI film and the PET protective film to match with the specification of the conductive foam to be manufactured.

Feeding: hanging the nickel-plated PI film and the PET protective film on a material placing frame 21, adjusting a width fixing buckle 24 to align with a feed inlet of a cavity 323, attaching the PET protective film on a conductive surface of the nickel-plated PI film during loading to obtain a conductive composite film 53, enabling the conductive composite film 53 to form a U-shaped structure according to the inner curved surface structure of the cavity 323, enabling two sides of the conductive composite film to be turned inwards to form a semi-coated structure when the conductive composite film with the U-shaped structure passes through the position between a mold core and the cavity, and referring to fig. 9 in the specific structure; then the conductive composite film 53 is inserted into the traction caterpillar 41 along the structural shape formed by the inner core needle 3317 and the material passing channel 3314; the mixed and blended liquid silica gel is filled in an EFD glue injection needle cylinder 3331 which is pressed by a screw, and the glue injection needle cylinder 3331 is arranged on a glue injection nozzle 3332.

Equipment debugging: the position of the inner core needle 3317 is adjusted, the glue injection port 3319 is used for drawing the crawler 41 direction, and the length of the inner core needle 3317 is 60 mm (the length of the inner core needle can be adjusted according to the colloid molding effect); the heating temperature of the heating base 3311 is set to 150 deg.C by the temperature sensor 3313 and the electric heater 3312, and the cold water chamber 332 is connected with an external water source, and is filled with circulating cooling water of about 5 deg.C; the speed of the traction crawler 41 is adjusted to 100mm/8 sec.

Glue injection molding: starting the glue injection device, injecting the liquid silica gel in the glue injection syringe 3331 into the coating cavity of the conductive composite film 53 through the glue injection port 3319, drawing the liquid silica gel by the drawing crawler 41, and allowing the liquid silica gel and the conductive composite film 53 to enter the curing component 331 together for heating and curing; and continuously drawing the product strips subjected to heat curing out by the continuous drawing of the drawing crawler 41, and cutting the product strips to a specified length on the material receiving platform 42 to obtain the conductive foam 5 shown in the structure of fig. 9.

Through detection, the surface resistance of the prepared conductive foam is less than 0.05 omega/inch²The recovery rate is more than 90 percent, the welding strength is more than 1500gf/cm, and the instant temperature resistance can reach 400 ℃.

Application example 2

The conductive foam provided in application example 2 is prepared by adopting a half-height structure core strip and a liquid silica gel injection mode.

Preparing raw materials: the colloid is liquid silica gel with the viscosity of 2000 mPa.s, a flame retardant accounting for 15 percent of the total weight of the liquid silica gel and silica gel color paste accounting for 0.1 percent of the total weight of the liquid silica gel are added into the liquid silica gel, and the mixture is stirred and mixed uniformly; the conductive film 51 is a nickel-plated PI film with the thickness of 15 micrometers, a surface treatment agent is coated on the insulating surface of the nickel-plated PI film, the wettability of the insulating surface of the nickel-plated PI film is improved, and the bonding strength between the liquid silica gel and the nickel-plated PI film is enhanced; the protective film 52 is a PET protective film with the thickness of 25 μm; coiling and cutting the nickel-plated PI film and the PET protective film to match the specification of the conductive foam to be manufactured; half high structure core 541 chooses for use prefabricated half high silica gel core 54's inside has seted up structure chamber 55 along length direction.

Feeding: loosening the bolts on the fixing seat of the inner core needle 3317 to take the inner core needle 3317 off the heating base 3311; the nickel-plated PI film and the PET protective film 52 are hung on the material placing frame 21, the width fixing buckle 24 is adjusted to align with a feed inlet of the cavity 323, the PET protective film is attached to a conductive surface of the nickel-plated PI film during loading to obtain a conductive composite film 53, the conductive composite film 53 is made to form a U-shaped structure according to the inner curved surface structure of the cavity 323, the conductive composite film with the U-shaped structure passes through the position between the mold core and the cavity, and two sides of the conductive composite film are turned inwards to form a semi-coated structure, and the specific structure is shown in figure 10; then the conductive composite film 53 and the prefabricated half-height silica gel core strip 54 are penetrated together from the feed inlet of the material passing channel 3314 to the traction caterpillar band 41, and the conductive composite film 53 wraps the prefabricated half-height silica gel core strip 54; the mixed and blended liquid silica gel is filled in an EFD glue injection needle cylinder 3331 which is pressed by a screw, and the glue injection needle cylinder 3331 is arranged on a glue injection nozzle 3332.

Equipment debugging: the heating temperature of the heating base 3311 is set to 150 deg.C by the temperature sensor 3313 and the electric heater 3312, and the cold water chamber 332 is connected with an external water source, and is filled with circulating cooling water of about 5 deg.C; and adjusting the speed of the traction crawler 41 to be 90 mm/8 seconds.

Injecting glue and forming: starting the glue injection equipment, and injecting the liquid silica gel in the glue injection syringe 3331 into the upper part of the prefabricated half-height silica gel core strip 54 in the coating cavity of the conductive composite film 53 through the glue injection port 3319; the conductive composite film 53, the prefabricated half-height silica gel core strip 54 and the liquid silica gel are fed into the curing component 331 together for heating and curing under the traction of the traction crawler 41, and a silica gel filling layer 542 is formed after the liquid silica gel is cured; and continuously pulling the product strips subjected to heat curing out forwards through the continuous traction of the traction crawler 41, and cutting the product strips to a specified length on the material receiving platform 42 to obtain the conductive foam 5 shown in the structure of fig. 10.

Through detection, the surface resistance of the prepared conductive foam 5 is less than 0.05 omega/inch²The recovery rate is more than 90 percent, the welding strength is more than 1500gf/cm, and the instant temperature resistance can reach 400 ℃.

Application example 3

In application example 3, the conductive foam 5 is prepared by using a full-size core bar and a liquid silica gel glue injection method.

Preparing raw materials: the colloid is liquid silica gel with the viscosity of 100 mPa.s, and a flame retardant accounting for 15 percent of the total weight of the liquid silica gel is added into the liquid silica gel and is stirred and mixed uniformly; the conductive film 51 is a nickel-plated PI film with the thickness of 15 microns, and plasma treatment is performed on the insulating surface of the nickel-plated PI film, so that the wettability of the insulating surface of the nickel-plated PI film is improved, and the bonding strength between the liquid silica gel and the nickel-plated PI film is enhanced; the protective film 52 is a PET protective film with the thickness of 40 μm; coiling and cutting the nickel-plated PI film and the PET protective film to match the specification of the conductive foam to be manufactured; full-size core strip 543 chooses prefabricated full-size silica gel core strip for use, and the inside of prefabricated full-size silica gel core strip has seted up structure chamber 55 along length direction.

Feeding: loosening the bolts on the fixing seat of the inner core needle 3317 to take the inner core needle 3317 off the heating base 3311; the nickel-plated PI film and the PET protective film 52 are hung on the material placing frame 21, the width fixing buckle 24 is adjusted to align with a feed inlet of the cavity 323, the PET protective film is attached to a conductive surface of the nickel-plated PI film during loading to obtain a conductive composite film 53, the conductive composite film 53 is made to form a U-shaped structure according to the inner curved surface structure of the cavity 323, the conductive composite film with the U-shaped structure passes through the position between the mold core and the cavity, and two sides of the conductive composite film are turned inwards to form a semi-coated structure, and the specific structure is shown in figure 11; and then the conductive composite film 53 and the prefabricated full-size silica gel core strip are penetrated to the traction caterpillar band 41 from the feed inlet of the material passing channel 3314 together, the prefabricated full-size silica gel core strip is wrapped by the conductive composite film 53, the prepared liquid silica gel is filled in an EFD glue injection needle cylinder 3331 pressed by a screw, and the glue injection needle cylinder 3331 is installed on a glue injection nozzle 3332.

Equipment debugging: the heating temperature of the heating base 3311 is set to 150 deg.C by the temperature sensor 3313 and the electric heater 3312, and the cold water chamber 332 is connected with an external water source, and is filled with circulating cooling water of about 5 deg.C; the speed of the traction crawler 41 is adjusted to 1 m/min.

Injecting glue and forming: starting the glue injection device, injecting the liquid silica gel in the glue injection syringe 3331 into the conductive composite film 53 coating cavity through the glue injection port 3319, and filling the liquid silica gel in the gap between the full-size silica gel core strip and the conductive composite film 53 in a flowing manner to form an adhesive layer 544; the conductive composite film 53 and the prefabricated full-size silica gel core strip enter a curing component 331 together for heating and curing under the traction of a traction crawler 41; and continuously pulling the product strips subjected to heat curing out forwards through the continuous traction of the traction crawler 41, and cutting the product strips to a specified length on the material receiving platform 42 to obtain the conductive foam 5 shown in the structure of fig. 11.

Application example 4

Application example 4 is to prepare the conductive foam by using a foam material, colloid injection and conductive cloth coating, and the difference from application example 3 is as follows: selecting conductive cloth to replace a nickel-plated PI film; selecting foamed foam to replace a prefabricated full-size silica gel core strip; the liquid silica gel was replaced with a glue adhesive (KF-955 treating agent, X-93-1684A glue, CAT-PL-56B glue, and a binder obtained by mixing the three agents), and the balance was the same as in application example 3.

By combining the application examples, the conductive foam injection molding device and the conductive foam injection molding process provided by the technical scheme of the application have the advantages that the conductive film, the core strip and the colloid are various in selectivity, and the conductive film can be made of various film materials with conductive properties; the core strip material can be injected and filled with liquid colloid and cured for molding, and also can be coated and molded by selecting a slightly smaller prefabricated core strip produced by matching process. The method can effectively solve the problem of dimensional tolerance of the core body while improving the diversity of the production process of the product, and improve the comprehensive yield and the product performance of the product.

The above embodiments are preferred embodiments of the present application, and the protection scope of the present application is not limited by the above embodiments, so: all equivalent changes made according to the structure, shape and principle of the present application shall be covered by the protection scope of the present application.

Claims

1. The utility model provides a cotton injection moulding device of electrically conductive bubble which characterized in that: comprises a feeding mechanism (2), an injection molding mechanism (3) and a receiving mechanism (4) which are arranged in sequence along the advancing direction of a conductive film (51); the injection molding mechanism (3) comprises a conductive film molding component (32) and a colloid injection molding component (33) which are sequentially arranged along the advancing direction of the conductive film (51); the conductive film forming assembly (32) is used for rolling and forming the conductive film (51) to obtain a conductive film coating cavity; the colloid injection molding assembly (33) is used for injecting colloid into the conductive film coating cavity and curing and molding.

2. The device for injection molding conductive foam according to claim 1, wherein: the conductive film forming assembly (32) comprises a forming base (322), and a cavity (323) with a U-shaped longitudinal section horizontally penetrates through the forming base (322); and a core (324) matched with the cavity (323) is fixed on the forming base (322).

3. The device for injection molding of the conductive foam according to claim 2, wherein: the cavity (323) comprises a feeding section (3231), a necking section (3232) and a discharging section (3233) which are continuous along the advancing direction of the conductive film (51), and the width of the necking section (3232) is gradually reduced along the advancing direction of the conductive film (51).

4. The device for injection molding of the conductive foam according to claim 1, wherein: the colloid molding component comprises a heating base (3311) and a glue injection needle cylinder (3331) fixed on the heating base (3311), and an electric heater (3312) is arranged on the heating base (3311); a material passing channel (3314) penetrates through the heating base (3311) along the advancing direction of the conductive film (51), a glue injection port (3319) communicated with a glue outlet of the glue injection needle cylinder (3331) is formed in the top of the material passing channel (3314), and glue in the glue injection needle cylinder (3331) is injected into the conductive film coating cavity through the glue injection port (3319); an inner core needle (3317) is detachably connected to the heating base (3311), and the inner core needle (3317) is arranged in the material passing channel (3314) and is axially parallel to the material passing channel (3314).

5. The device for injection molding of the conductive foam according to claim 4, wherein: the inner core needle (3317) is provided with a through hole (33171) along the axial direction.

6. The device for injection molding of the conductive foam according to claim 4, wherein: the heating base (3311) is further provided with a cold water cavity (332), the cold water cavity (332) is located under the glue injection needle cylinder (3331), and the cold water cavity (332) is communicated with an external water source.

7. An injection molding device for conductive foam (5) according to claim 1, characterized in that: the feeding mechanism (2) comprises a feeding frame (21), a feeding roller (22) and a limiting roller (23) are arranged on the feeding frame (21), a width fixing buckle (24) is arranged on the limiting roller (23), and the height of the discharging position of the width fixing buckle (24) is not higher than that of the feeding hole of the conductive film forming assembly (32).

8. The device for injection molding of the conductive foam according to claim 1, wherein: the receiving mechanism (4) comprises a receiving platform (42) and a traction crawler (41), and the traction crawler (41) is positioned between the receiving platform (42) and the injection molding mechanism (3); the traction crawler (41) comprises an upper traction crawler (411) and a lower traction crawler (412) which rotate in opposite directions, and a gap which is used for the electric foam (5) to pass through and is adjustable in height is reserved between the upper traction crawler (411) and the lower traction crawler (412).

9. An injection molding process of conductive foam by using the device for injection molding of conductive foam according to any one of claims 1 to 8, comprising the steps of:

feeding: placing the conductive film (51) in the feeding mechanism (2), drawing the front end of the conductive film (51) to sequentially pass through the conductive film forming assembly (32) and the colloid injection molding assembly (33) to the receiving mechanism (4), and rolling and molding the conductive film (51) through the conductive film forming assembly (32) to obtain a conductive film coating cavity;

injection molding: starting the material receiving mechanism (4) to drive the conductive film (51) to move, and controlling the moving speed to be 0.5-2 m/min; injecting colloid with the viscosity of 80-2000 mPa.s into the conductive film coating cavity through a colloid injection molding assembly (33), and heating to 60-150 ℃ to solidify and mold the colloid;

receiving: and (5) dragging the formed product to a material receiving mechanism (4), and slitting to obtain a product strip with a specified length.