A vulcanization molding method and molding die for cable connectors

Abstract

This invention provides a method and mold for vulcanizing cable connectors. The vulcanization process includes: surface pretreatment for vulcanization, preforming a preform, and fixing the preform and unvulcanized cable connector to an injection molding vulcanization mold. The preform is placed in a first mold cavity formed between a first mold and a second mold. The injection molding mold injects adhesive using a fast-then-slow injection method, followed by a stepped heating process. Heating is then stopped, and the mold is allowed to cool down before demolding and product removal. This invention combines preforming with injection molding, avoiding the long injection time and the potential for cable deformation and displacement due to the pressure generated by the adhesive flow, which can affect the product's appearance. This method is applicable to various cable connector specifications.

Description

Technical Field

[0001] This invention relates to the field of cable connector manufacturing technology, and more specifically, to a vulcanization molding method and molding die for cable connectors. Background Technology

[0002] Cable connectors consist of three parts: the cable, the metal components, and the sealing layer. The sealing layer wraps around the cable to protect it, providing a seal and limiting displacement. Mechanical seals and elastomer sealing are the most common types. When using injection molding to form the sealing layer, especially when the sealing layer is large, the impact of the large flow of adhesive can easily cause the internal cable to shift, resulting in exposed cables and affecting the product's appearance. Prolonged injection time can also lead to uneven curing, affecting product quality, and resulting in low efficiency and wasted time and equipment.

[0003] The invention patent "A Method for Vulcanizing and Sealing Cable Outlet of an Electrical Connector" (application number: CN201610319135.3) proposes a method for cold vulcanizing and sealing cables at the outlet of an electrical connector. The mold is fixed to the outlet position by clamps, and then cold vulcanization is performed to obtain a sealed structure. The invention patent "Cable Connector and Its Manufacturing Method" (application number: CN02113027.2) proposes a cable connection device in which an outer preform, an inner preform, and a metal insert are placed in a mold cavity; the components are then bonded together using a thermoplastic elastomer. Neither of these examples involves the positioning of the metal parts and the cable, nor does it involve the vulcanization molding process. Summary of the Invention

[0004] To address the aforementioned issues, this invention provides a vulcanization molding method and mold suitable for cable connectors. By pre-forming a preform and then using injection molding to vulcanize the cable connector, a sealing layer is formed through injection molding. This is particularly beneficial when the sealing layer is large, preventing internal cables from shifting under the impact of large amounts of flowing adhesive, thus avoiding cable exposure and affecting product appearance. Furthermore, it shortens injection time, resulting in more uniform vulcanization, thereby improving product quality and efficiency while reducing production costs.

[0005] The first objective of this invention is to disclose a vulcanization molding method for cable connectors, comprising the following steps:

[0006] S1: Perform surface pretreatment for vulcanization on the areas of cables and metal parts to be vulcanized;

[0007] S2: Pre-forming mold pre-forms the plastic blank and demolds it;

[0008] S3: The preform and the unvulcanized cable connector are fixedly installed to the injection molding mold. The injection molding mold includes a first mold, a second mold, a metal end positioning block and a cable end positioning block. The metal end positioning block and the cable end positioning block are fixed on the metal part and the cable of the unvulcanized cable connector. The preform is applied to the first mold cavity formed between the first mold and the second mold.

[0009] S4: After confirming the mold closing, the injection vulcanizing mold is injected with glue in a fast-then-slow manner, and then the injection vulcanizing mold is heated in a step-by-step heating method.

[0010] S5: Stop heating and wait for the injection vulcanization molding mold to cool down before opening the mold and demolding the product.

[0011] Furthermore, in step S1, the metal part is made of 304, 316L, TC4 or TC6 alloy, and the metal part is provided with a wiring channel for the cable to enter and exit. The cable is directly inserted or stripped to obtain the core wire and then passed through the wiring channel. The areas of the cable and the metal part to be vulcanized are polished with sandpaper, and then the polished surfaces are cleaned with acetone using a non-woven cloth and allowed to air dry naturally.

[0012] Furthermore, in step S2, the rubber material is pressed and cut by an open mill to prepare rubber strips. The rubber strips are laid into the concave mold of the preforming mold. A release cloth is laid in the preforming mold for demolding the preform. After demolding, the preform is trimmed for later use.

[0013] Furthermore, in step S2, the preformed mold has two mirror-symmetrical cavities in its concave mold. When the preformed mold is closed, a U-shaped cavity is formed between the preformed mold's convex mold and the preformed mold's concave mold.

[0014] Furthermore, in step S3, an adhesive layer is coated on the metal part, and the adhesive layer is sandwiched between the interface of the metal part and the sealing layer.

[0015] Furthermore, step S3 details the steps as follows:

[0016] S31: Before molding the unvulcanized cable connector, fix the metal end positioning block to the metal part and the cable end positioning block to the cable.

[0017] S32: The preformed rubber blank is applied to the cavities of the first mold and the second mold; when the unvulcanized cable connector is installed, the limiting post of the metal end positioning block is embedded in the second groove of the second mold, and the limiting block is tightly attached to the metal part to fix it.

[0018] S33: The pressure block is fixedly installed on the first mold and the second mold, and at the same time the cable end positioning block is fixed on the second step of the second mold to seal the adhesive and limit the cable displacement.

[0019] S34: The vulcanizing equipment drives the first mold and / or the second mold to move, and the first groove and the first step of the first mold are respectively aligned with the protrusion of the metal end positioning block and the boss of the cable end positioning block, so that the injection vulcanizing molding mold is closed.

[0020] S35: In the closed state of the injection molding mold, the first mold, the second mold, the cable end positioning block, the metal end positioning block, the cable and the metal part form a first mold cavity. The first mold cavity is used to inject rubber material to form a cable connector. The pressure block is fixedly installed on the pressure block.

[0021] Furthermore, in step S3, there is one cable; or, there are multiple cables, which are arranged perpendicular to the cable end positioning block, and the multiple cables are one or more combinations of cables with various diameter specifications.

[0022] Furthermore, in step S3, the injection vulcanization molding die also includes a wire pressing block. When processing cables of different specifications and arrangements, the cable end positioning block and the wire pressing block with corresponding through holes are replaced to fix the cable.

[0023] Furthermore, in step S4, the injection molding mold uses a fast-then-slow injection method, including the following two stages:

[0024] The first stage of glue injection is V1, and the glue injection time t1 is 0.5t;

[0025] The second stage adhesive injection volume is V2, and the adhesive injection time t2 is 0.5t;

[0026] Where V1+V2=V; V1>V2; V is the total glue injection volume; t is the total glue injection time;

[0027] The heating method of step-by-step heating for injection vulcanization molding includes the following three stages:

[0028] The first stage heating temperature is T1, and the holding time is t3;

[0029] The second stage heating temperature is T2, and the holding time is t4;

[0030] The third stage heating temperature is T3, and heating is stopped after holding for t5.

[0031] Among them, T1 <T2<T3;t3<t4<t5。

[0032] The second objective of this invention discloses a vulcanization molding die for cable connectors, comprising: a base plate, a second mold, a first mold, and a first mold cavity. A metal end positioning block and a cable end positioning block are respectively provided at both ends of the first mold cavity. The metal end positioning block is used to limit and fix a metal component, and the cable end positioning block is used to limit and fix a cable. A pressure block and a wire-pressing block are provided on the outer side of the cable end positioning block. The cable passes through the through holes on the wire-pressing block and the cable end positioning block and is fixedly connected to the metal component. The metal component is connected to the limiting block, and the limiting block is fixed to the base plate to restrict the axial movement of the metal component.

[0033] Compared with existing technologies, the vulcanization molding method and molding die for cable connectors described in this invention have the following advantages:

[0034] 1. This invention uses a pre-forming combined with injection molding process to avoid the problems associated with a single injection molding process, which has a long injection time and the pressure generated by the flow of the adhesive can easily cause the cables inside the mold cavity to deform and shift, resulting in exposed cables and affecting the appearance of the product.

[0035] 2. This invention, by setting cable end positioning blocks and wire clamping blocks with variable through-hole size and quantity, can be adjusted according to actual conditions to be suitable for cables of various specifications.

[0036] 3. The present invention fixes the unvulcanized cable connector by setting a limiting block, a metal end positioning block, a cable end positioning block, a pressure block and a wire pressing block, thereby limiting the displacement of the metal parts and the cable in the mold cavity.

[0037] 4. This invention reduces the amount of glue injected by preforming the preform, greatly shortens the injection time, avoids uneven vulcanization caused by prolonged injection, and improves molding quality. Attached Figure Description

[0038] Figure 1 This is a schematic diagram of the structure of the vulcanization injection mold described in this invention;

[0039] Figure 2 This is a schematic diagram of the connector structure according to an embodiment of the present invention;

[0040] Figure 3 This is a front view of the connector according to an embodiment of the present invention;

[0041] Figure 4 This is a left view of the connector according to an embodiment of the present invention;

[0042] Figure 5 This is a schematic diagram of the pressure block and pressure block structure of the present invention;

[0043] Figure 6 This is a schematic diagram of the cable end positioning block, wire pressing block, and pressing block structure of the present invention;

[0044] Figure 7 This is a front view of the metal positioning block described in this invention;

[0045] Figure 8 This is a top view of the vulcanizing injection mold described in this invention;

[0046] Figure 9 This is a cross-sectional view of the preform mold of the present invention;

[0047] Figure 10 This is a top view of the preform mold of the present invention.

[0048] Explanation of reference numerals in the attached figures:

[0049] 1. Metal end positioning block; 101. Limiting post; 2. First mold; 201. First step; 202. First groove; 3. Cable end positioning block; 301. Boss; 302. First through hole; 4. Pressing block; 401. Upper pressing block; 402. Lower pressing block; 5. Wire pressing block; 501. First wire pressing block; 502. Second wire pressing block; 503. Second through hole; 6. Second mold; 601. Second step; 602. Second groove; 7. Limiting block; 8. Base plate; 9. Metal part; 901. Wiring terminal; 902. Body; 903. Fixed end; 10. Cable; 11. Flow channel; 12. Covering and sealing layer; 13. Punch; 14. Die; 15. U-shaped mold cavity; 16. First mold cavity. Detailed Implementation

[0050] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0051] The first objective of this invention is to provide a vulcanization molding method for cable connectors, comprising the following steps:

[0052] S1: Pre-treatment of vulcanized surface; The areas of the cable 10 and metal parts 9 to be vulcanized are sanded with sandpaper, and then the sanded surfaces are cleaned with anhydrous ethanol or acetone using a non-woven cloth and then air-dried.

[0053] S2: Pre-formed preform; the rubber material is pressed and cut by an open mill to prepare rubber strips, which are then laid into the concave mold of the pre-forming mold. A release cloth is laid in the pre-forming mold for demolding the preform. After demolding, the preform is trimmed and ready for use.

[0054] Preferably, the dimensions of a single chamber of the U-shaped mold cavity 15 are: 50mm≤e≤350mm, 20mm≤d≤160mm, 500mm≤f≤1000mm, and the wall thickness is 10~40mm;

[0055] S3: The pre-made rubber blank and the unvulcanized cable connector are fixedly installed in the mold; the specific steps are as follows:

[0056] S31: Before the unvulcanized cable connector is installed, fix the metal end positioning block 1 on the metal part 9 and fix the cable end positioning block 3 on the cable 10.

[0057] S32: The preformed rubber blank is applied to the cavity of the first mold 2 and the second mold 6; when the unvulcanized cable connector is installed, the limiting post 101 of the metal end positioning block 1 is embedded in the second groove 602 of the second mold 6, and the limiting block 7 is tightly attached to the metal part 9 to fix it.

[0058] S33: The pressure block 4 is fixedly installed on the first mold 2 and the second mold 6, and at the same time, the cable end positioning block 3 is fixed on the second step 601 of the second mold 6, which is used to seal the adhesive and limit the displacement of the cable 10.

[0059] S34: The vulcanizing equipment drives the first mold 2 and / or the second mold 6 to move. The first groove 202 and the first step 201 of the first mold 2 are respectively aligned with the protrusion of the metal end positioning block 1 and the boss 301 of the cable end positioning block 3, so that the injection vulcanizing molding mold is closed.

[0060] S35: In the closed state of the injection molding mold, the first mold 2, the second mold 6, the cable end positioning block 3, the metal end positioning block 1, the cable 10 and the metal part 9 form a first mold cavity 16, which is used to inject the rubber material to form the cable connector; the wire pressing block 5 is fixedly installed on the pressing block 4;

[0061] S4: Mold closing, injection molding, and pressure vulcanization; Specific operating steps:

[0062] S41: Control the injection speed during glue injection, and adopt a glue injection method of fast first and then slow;

[0063] S42: The injection vulcanizing mold is heated using a stepped heating method;

[0064] S5: Stop heating and wait for the injection molding mold to cool down before opening the mold and demolding the product.

[0065] Ideally, after heating is stopped, the injection molding vulcanization mold should be cooled down naturally.

[0066] By combining preforming with injection molding, the single injection molding process is avoided. This avoids the long injection time and the pressure generated by the flowing rubber material, which can cause deformation and displacement of the cables inside the first mold cavity 16, resulting in exposed cables and affecting the product's appearance. Simultaneously, preforming the rubber preform reduces the amount of rubber injected, significantly shortening the injection time and preventing uneven vulcanization caused by prolonged injection, thus improving molding quality. Rubber is a poor conductor of heat, and the uneven temperature rise inside and outside large products has always been a challenge in the field. Using segmented heating helps maintain temperature consistency inside and outside the product, ensuring uniform vulcanization and improving product quality.

[0067] Specifically, in step S1, the metal part 9 is made of 304, 316L, TC4, or TC6 alloy. The metal part 9 has a wiring channel for cable entry and exit. The cable 10 is inserted directly or after stripping the core wire, through the wiring channel. The areas of the cable 10 and the metal part 9 to be vulcanized are sanded using sandpaper, and then the sanded surfaces are cleaned with acetone using a non-woven cloth and allowed to air dry. This arrangement facilitates a secure connection between the metal part 9 and the cable 10, improving the reliability of the product connection.

[0068] Specifically, in step S2, the rubber compound is pressed into a sheet with a width of 400-600 mm and a length of 1000-1500 mm using an open mill. This sheet is then cut into strips with a length of 200-400 mm and a width of 40-80 mm. The vulcanizing equipment drives the punch 13 of the preforming mold to descend and close with the cavity 14 of the preforming mold, forming a U-shaped cavity 15. The rubber strips are laid in the cavity 14 of the preforming mold, and the preform is trimmed after demolding. Because chloroprene rubber and other rubber compounds have high viscosity, using a release cloth can better assist in demolding, avoiding the impact of release agents on subsequent injection vulcanization and ensuring the quality of fusion between the rubber compounds.

[0069] Specifically, in steps S2 and S4, the rubber compound is one or more of chloroprene rubber, chlorosulfonated polyethylene rubber, and nitrile rubber, used in combination. This configuration allows for the creation of products with diverse physical properties, better meeting the requirements of various working environments and occasions.

[0070] Specifically, in step S2, the preforming conditions for the preform include: time 15-25 min, temperature 50-60℃, and pressure 10-15 MPa. This setting helps to achieve the goal of rapidly processing and molding the preform that meets the requirements.

[0071] Specifically, in step S3, an adhesive layer is coated onto the metal part, and the adhesive layer is sandwiched between the metal part and the sealing layer. This adhesive layer can bond the rubber and metal through vulcanization, improve the bonding performance, ensure the connection quality between the rubber and the metal part 9, and improve the stability of the product.

[0072] Specifically, in step S2, the preforming mold has two mirror-symmetrical cavities in its concave mold. When the preforming mold is closed, a U-shaped cavity 15 is formed between the preforming mold's convex mold 13 and the preforming mold's concave mold 14. This design allows for the molding of two preforms at once, meeting the vulcanization requirements of a single connector. It features a simple structure, streamlined operation, and improved production efficiency.

[0073] Specifically, in step S3, there is one cable 10; or, there are multiple cables 10, which are set perpendicular to the cable end positioning block 3, and the multiple cables 10 are one or more combinations of cables with various diameter specifications.

[0074] Preferably, the number of cables 10 is 1 to 3, arranged horizontally or vertically, and the cables 10 have one or more combinations of diameters of 65±1.5mm, 55±1.5mm, 45±1.5mm, 35±1.5mm, and 25±1.5mm; each cable may have 1 to 3 internal cores. This arrangement can enrich the product range and meet the requirements of various working environments and occasions.

[0075] Specifically, in step S3, the injection molding vulcanization mold also includes a wire pressing block 5. When processing cables 10 of different specifications and arrangements, the cable end positioning block 3 and the wire pressing block 5 with corresponding through holes are replaced to fix the cable 10. This setting increases the restriction and fixation of the cable 10 by the wire pressing block 5, solves the problem of displacement that has occurred when the cable end positioning block 3 fixes the cable with a single hole, which is conducive to further improving product quality. At the same time, it is conducive to better molds according to product types, expanding the mold processing range, and reducing production costs.

[0076] Specifically, in step S4, the injection molding mold uses a fast-then-slow injection method, including the following two stages:

[0077] The first stage of glue injection is V1, and the glue injection time t1 is 0.5t;

[0078] The second stage adhesive injection volume is V2, and the adhesive injection time t2 is 0.5t;

[0079] Where V1+V2=V; V1>V2; V is the total glue injection volume; t is the total glue injection time;

[0080] The heating method of step-by-step heating for injection vulcanization molding includes the following three stages:

[0081] The first stage heating temperature is T1, and the holding time is t3;

[0082] The second stage heating temperature is T2, and the holding time is t4;

[0083] The heating temperature T3 in the third stage is maintained for a holding time t5 and then the heating is stopped;

[0084] Among them, T1 < T2 < T3; t3 < t4 < t5. The injection speed of the glue is first fast and then slow, which is beneficial to reducing the impact of the pressure generated by the flow of the glue on the cable, reducing the displacement of the internal cable 10, and further improving the product quality; as rubber is a poor conductor of heat, the problem of uneven temperature rise inside and outside the product with a large size has always been a difficult point in the field. Using staged stepped heating helps to maintain the consistency of the temperature inside and outside the product, ensure uniform vulcanization, and improve the product quality.

[0085] Preferably, the specific process of injecting glue is as follows: the injection volume V1 in the first stage is 0.6 - 0.8V, and the injection time t1 is 0.5t; the injection volume V2 in the second stage is 0.4 - 0.2V, and the injection time t2 is 0.5t; the total injection time t is 5 - 10 min.

[0086] Preferably, V1 is 0.7V and V2 is 0.3V.

[0087] Preferably, the specific heating process is as follows: the heating temperature T1 in the first stage: 50°C to 100°C, the holding time t3: 0.3 h to 1 h; the heating temperature T2 in the second stage: 70°C to 115°C, the holding time t4: 0.5 - 1.5 h; the heating temperature T3 in the third stage: 110°C to Y160°C, the holding time t5: 3 h - 6 h and then the heating is stopped.

[0088] The second object of the present invention is to disclose a vulcanization molding die suitable for a cable connector, including: a bottom plate 8, a second die 6, a first die 2, and a first die cavity 16. Metal end positioning blocks 1 and cable end positioning blocks 3 are respectively arranged at both ends of the first die cavity 16. The metal end positioning block 1 is used to limit and fix the metal part 9, and the cable end positioning block 3 is used to limit and fix the cable 10. A pressing block 4 and a wire pressing block 5 are arranged outside the cable end positioning block 3. The cable 10 passes through the through holes on the wire pressing block 5 and the cable end positioning block 3 and is fixedly connected to the metal part 9; the metal part 9 is connected to the limiting block 7, and the limiting block 7 is fixed on the bottom plate 8 to limit the axial movement of the metal part 9.

[0089] A metal end positioning block 1 is arranged at one end of the first die cavity 16, and the main body 902 of the metal part 9 is fixedly connected to the metal end positioning block 1, which is beneficial to better fixing the metal part 9, bearing the pressure generated by the flow of the glue during the injection and vulcanization process, and avoiding the displacement and deflection of the metal part 9 due to the acting force, which affects the appearance of the product; the metal part 9 further includes a wiring end 901. A cable end positioning block 3 arranged at the other end of the first die cavity 16 and the pressing block 4 and the wire pressing block 5 outside the cable end positioning block 3. The cable 10 passes through the through holes on the pressing block 4 and the wire pressing block 5 and is connected to the metal part 9. This setting helps to fix the cable 10 and avoid the deformation and displacement of the multi-strand cable 10 due to the pressure of the glue flow, resulting in the exposure of the cable 10.

[0090] Preferably, the contact surface between the limiting block 7 and the fixed end 903 of the metal part 9 is a curved surface or a flat surface. The limiting block 7 is fixed to the base plate 8 by screws to axially limit the metal part 9 and prevent the metal part 9 from axially displacing during vulcanization.

[0091] Specifically, the metal end positioning block 1, cable end positioning block 3, clamping block 4, and clamping block 5 are all modular structures. The modular design of each component facilitates mold replacement when producing cable connectors of different specifications and layouts, reducing mold changeover time and improving production efficiency.

[0092] Preferably, the metal end positioning block 1, the cable end positioning block 3, the pressure block 4, and the wire pressing block 5 are each horizontally or vertically symmetrical. This arrangement facilitates mold installation and use, reduces the number of parts, and streamlines production.

[0093] Preferably, the metal end positioning block 1 and the cable end positioning block 3 are connected by at least two screws to different sections; the pressure block 4 and the wire pressure block 5 are connected by at least six screws to different sections. The screw connection structure is simple, easy to install and disassemble, and low in cost; the multiple screw connections make the force on each part more even, which helps to improve the sealing of the first mold cavity 16 and ensure the quality of the injection vulcanized product.

[0094] Specifically, the first mold 2 is provided with a glue injection port, the first mold cavity 16 is provided with 3 to 5 flow channels 11, and the surfaces of the cavities of the first mold 2 and the second mold 6 are provided with 6 to 12 vent holes. The multiple flow channels 11 and vent holes help ensure uniform flow of the rubber material during the glue injection and vulcanization process, reducing the risk of excessive rubber flow pressure at a single injection port, which could affect the fixation of the cable 10 and the metal part 9. Simultaneously, it shortens the glue injection time, allowing the rubber material to fill the entire first mold cavity 16 more quickly, thus improving product quality and production efficiency.

[0095] Specifically, the axial cross-section of the first mold cavity 16 is rectangular, circular, straight, U-shaped, or L-shaped, consistent with the dimensions of the product's covering and sealing layer 12. This design can enrich product variety, meet the requirements of various working environments and occasions, expand the mold processing range, and help reduce production costs.

[0096] Preferably, the first mold cavity 16 consists of two mirror-symmetrical cavities, with a rectangular axial cross-section, a height of c, a width of b, and an axial length of a, wherein: 50mm≤b≤350mm, 50mm≤c≤350mm or 50mm≤b=c≤350mm, and 500mm≤a≤1000mm.

[0097] Specifically, the cable end positioning block 3 is provided with a ring of bosses 301. The first mold 2 and the second mold 6 are provided with a first step 201 and a second step 601 at corresponding positions. The bosses 301 cooperate with the first step 201 and the second step 601 to limit the radial displacement and right axial displacement of the cable end positioning block 3. This arrangement helps to install and fix the cable end positioning block 3 to the cable 10 and the injection vulcanization molding mold. The structure is simple, which helps to ensure the sealing of the first mold cavity 16. At the same time, it facilitates mold disassembly and installation and shortens the mold replacement time.

[0098] Specifically, the pressure block 4 has a through hole in the middle. The pressure block 4 is fixed to the first mold 2 and the second mold 6 by screws to limit the axial displacement of the cable end positioning block 3. This design facilitates the installation and fixation of the cable end positioning block 3 and improves the reliability of the sealing of the cable end positioning block 3.

[0099] Specifically, the pressure block 5 is fixed to the pressure block 4 with screws to limit the displacement of the cable 10 in the first mold cavity 16. This arrangement helps to fix the cable 10, prevents the cable 10 from being displaced due to the pressure generated by the flow of the adhesive, reduces the impact of the vibration of the cable 10 on the cable end positioning block 3, ensures the sealing of the first mold cavity 16, and facilitates mold disassembly and installation, shortening the mold replacement time.

[0100] The following describes in detail, with reference to the accompanying drawings, a method for vulcanizing and molding cable connectors and a molding die according to an embodiment of the present invention.

[0101] Example 1

[0102] The cable connector includes a sealing layer 12, a cable 10, and a metal part 9.

[0103] Specifically, metal part 9 is made of 316L stainless steel.

[0104] Specifically, there are 2 wiring channels, 10 vertically arranged cables, 2 cables, and a diameter of 65±1.5mm.

[0105] Specifically, the sealing layer 12 is in the shape of a straight line with a rectangular axial section, a height of c=180mm, a width of b=130mm, and an axial length of a=600mm.

[0106] Specifically, the sealing layer 12 is made of neoprene rubber.

[0107] Specifically, the adhesive layer sandwiched between the metal part 9 and the sealing layer 12 in the cable connector uses Chemlock 205 primer and 6150 surface treatment agent.

[0108] Specifically, step S1: vulcanization surface pretreatment; the areas of the cable 10 and metal parts 9 to be vulcanized are sanded with sandpaper, and then the sanded surfaces are cleaned with acetone using a non-woven cloth and allowed to air dry.

[0109] Specifically, step S2: Pre-forming preform; the rubber compound is pressed into a sheet with a width of 500mm and a length of 1000mm by an open mill, and then cut into strips with a length of 300mm and a width of 40mm; the vulcanizing equipment drives the upper forming punch 13 to descend and close with the lower forming die 14 to form a U-shaped mold cavity 15; the rubber strip is laid in the lower forming die 14, and the preform is trimmed after demolding.

[0110] Preforming conditions: time 20 min, temperature 60℃, pressure 12 MPa;

[0111] The dimensions of a single U-shaped mold cavity 15 are: e=130mm, d≤80mm, 500mm≤f=1000mm, and the wall thickness is 20mm.

[0112] Lay out a release liner to assist in demolding.

[0113] Specifically, step S3: The pre-made rubber blank and the unvulcanized cable connector are fixedly installed in the injection molding vulcanization mold; the specific steps are as follows:

[0114] S31: Before the unvulcanized cable connector is installed into the injection molding mold, the metal end positioning block 1 and the cable end positioning block 3 are fixed on the metal part 9 and the cable 10.

[0115] S32: The preformed rubber blank is applied to the cavity of the first mold 2 and the second mold 6; when the unvulcanized cable connector is installed, the limiting post 101 of the metal end positioning block 1 is embedded in the second groove 602 of the second mold 6, and the limiting block 7 is in close contact with the metal part 9 to fix the metal part 9.

[0116] S33: The upper pressure block 401 and the lower pressure block 402 of the pressure block 4 are respectively installed on the first mold 2 and the second mold 6 by screws. At the same time, the cable end positioning block 3 is fixed on the second step 601 of the second mold 6, which serves to seal the adhesive and limit the displacement of the cable 10.

[0117] S34: The vulcanizing equipment drives the first mold 2 to descend, and the first groove 202 and the first step 201 of the first mold 2 are respectively aligned with the protrusion of the metal end positioning block 1 and the boss 301 of the cable end positioning block 3, so that the injection vulcanizing molding mold is closed.

[0118] S35: When the injection molding vulcanization mold is closed, a first mold cavity 16 is formed between the first mold 2, the second mold 6, the cable end positioning block 3, the metal end positioning block 1, the cable 10 and the metal part 9. The first mold cavity 16 is used to inject rubber material to form a large cable connector. The first pressure block 501 and the second pressure block 502 of the pressure block 5 are respectively installed on the pressure block 4 by screws.

[0119] Specifically, step S4: mold closing, injection molding, and pressure vulcanization; operational steps:

[0120] S41: Specific process of glue injection: The first stage glue injection volume V1 is 0.7V, and the glue injection time t1 is 5min; the second stage glue injection volume V2 is 0.3V, and the glue injection time t2 is 5min;

[0121] S42: The specific heating process is as follows: the first stage is 80±2℃, held for 0.5h; the second stage is to raise the temperature to 100±2℃, held for 1h; the third stage is to raise the temperature to 120±2℃, held for 5h, and then stop heating.

[0122] S5: Demolding of the product; After heating is stopped, wait for the mold temperature to naturally drop below 60℃ before opening the mold and demolding the product.

[0123] Specifically, the injection molding vulcanization mold includes a base plate 8, a second mold 6, a first mold 2, a limiting block 7 set on the base plate 8, a metal end positioning block 1 and a cable end positioning block 3 set at both ends of the first mold cavity 16, and a pressing block 4 and a wire pressing block 5 set on the outside of the cable end positioning block 3.

[0124] Specifically, the cable 10 passes through the through holes of the cable end positioning block 3 and the wire clamping block 5, and the cable end positioning block 3 and the wire clamping block 5 are replaced to adapt to the cable 10 with a diameter of 65±1.5mm.

[0125] Specifically, the metal end positioning block 1, the cable end positioning block 3, and the wire clamping block 5 are vertically split structures; the clamping block 4 is a horizontally split structure. The different sections of the metal end positioning block 1 are connected by 2 screws, the different sections of the cable end positioning block 3 are connected by 3 screws, and the different sections of the clamping block 4 and the wire clamping block 5 are connected by 14 and 8 screws, respectively.

[0126] Specifically, the first mold 2 is provided with a glue injection port, and the glue injection port is provided with 3 flow channels 11 in the mold cavity. The mold cavity surfaces of the first mold 2 and the second mold 6 are provided with 12 venting holes.

[0127] Specifically, the contact surface between the limiting block 7 and the metal part 9 is curved or flat. The limiting block 7 is fixed to the base plate 8 by screws to axially limit the metal part 9 and prevent the metal part 9 from axially displacing during vulcanization.

[0128] Specifically, the metal end positioning block 1 is provided with 1 to 2 sets of limiting posts 101, and the first mold 2 and the second mold 6 are provided with a corresponding number of first grooves 202 and second grooves 602. The limiting posts 101 can be embedded in the first grooves 202 and the second grooves 602 to prevent the metal end positioning block 1 from moving axially.

[0129] Specifically, the cable end positioning block 3 is provided with a ring of bosses 301, and the first mold 2 and the second mold 6 are provided with a first step 201 and a second step 601 at corresponding positions, with the bosses 301 matching the first step 201 and the second step 601; the pressure block 4 and the wire pressing block 5 are provided with through holes, and the pressure block 4 is fixed on the first mold 2 and the second mold 6 by screws; the wire pressing block 5 is fixed on the pressure block 4 by screws, and at the same time, the cable end positioning block 3 is fixed between the first mold 2 and the second mold 6 to prevent the cable 10 from shifting in the first mold cavity 16.

[0130] It should be understood that the described embodiments are some, but not all, of the embodiments of the present invention. The specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. Although the invention has been disclosed above, it is not limited thereto. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the invention; therefore, the scope of protection of the invention should be determined by the scope defined in the claims.

Claims

1. A vulcanization molding method for cable connectors, characterized in that, Includes the following steps: S1: Perform surface pretreatment for vulcanization on the areas of cables and metal parts to be vulcanized; S2: Pre-forming mold pre-forms the plastic blank and demolds it; S3: The preform and the unvulcanized cable connector are fixedly installed to the injection molding mold, which includes a first mold (2), a second mold (6), a metal end positioning block (1) and a cable end positioning block (3). The metal end positioning block (1) and the cable end positioning block (3) are fixed on the metal part (9) and the cable (10) of the unvulcanized cable connector. The preform is applied to the first mold cavity (16) formed between the first mold (2) and the second mold (6). S31: Before the unvulcanized cable connector is installed, the metal end positioning block (1) is fixed on the metal part (9), and the cable end positioning block (3) is fixed on the cable (10); S32: The preformed rubber blank is applied to the cavity of the first mold (2) and the second mold (6); when the unvulcanized cable connector is installed, the limiting post (101) of the metal end positioning block (1) is embedded in the second groove (602) of the second mold (6), and the limiting block (7) is close to the metal part (9) to fix it. S33: The pressure block (4) is fixedly installed on the first mold (2) and the second mold (6), and the cable end positioning block (3) is fixed on the second step (601) of the second mold (6) to seal the adhesive and limit the displacement of the cable (10); S34: The vulcanizing equipment drives the first mold (2) and / or the second mold (6) to move. The first groove (202) and the first step (201) of the first mold (2) are respectively aligned with the protrusion (102) of the metal end positioning block (1) and the boss (301) of the cable end positioning block (3), so that the injection vulcanizing molding mold is closed. S35: When the injection molding mold is closed, a first mold cavity (16) is formed between the first mold (2), the second mold (6), the cable end positioning block (3), the metal end positioning block (1), the cable (10), and the metal part (9). The first mold cavity (16) is used to inject rubber material to form a cable connector. The wire pressing block (5) is fixedly installed on the pressing block (4). S4: After confirming the mold closing, the injection molding mold is injected with glue in a fast-then-slow manner, and then the injection molding mold is heated in a step-by-step heating method. S5: Stop heating and wait for the injection vulcanization molding mold to cool down before opening the mold and demolding the product.

2. The vulcanization molding method for cable connectors as described in claim 1, characterized in that, In step S1, the metal part is made of 304, 316L, TC4 or TC6 alloy. The metal part is provided with a wiring channel for the cable to enter and exit. The cable is directly inserted or stripped to obtain the core wire and then passed through the wiring channel. The area to be vulcanized of the cable and the metal part is polished with sandpaper. Then, the polished surface is cleaned with acetone using a non-woven cloth and then air-dried.

3. The vulcanization molding method for cable connectors as described in claim 1, characterized in that, In step S2, the rubber material of the preform is pressed and cut into rubber strips by an open mill. The rubber strips are laid into the concave mold of the preforming mold. A release cloth is laid in the preforming mold for demolding the preform. After demolding, the preform is trimmed and ready for use.

4. The vulcanization molding method for cable connectors as described in claim 3, characterized in that, In step S2, the preformed mold has two mirror-symmetrical cavities in the concave mold. When the preformed mold is closed, the preformed mold's punch (13) and the preformed mold's concave mold (14) form a U-shaped cavity (15).

5. The vulcanization molding method for cable connectors as described in claim 1, characterized in that, In step S3, an adhesive layer is coated on the metal part, and the adhesive layer is sandwiched between the interface of the metal part and the sealing layer.

6. The vulcanization molding method for cable connectors as described in claim 1, characterized in that, In step S3, the cable (10) is one; or, the cable (10) is multiple, the cable (10) is set perpendicular to the cable end positioning block (3), and the multiple cables (10) are one or more combinations of cables with various diameter specifications.

7. The vulcanization molding method for cable connectors as described in claim 1, characterized in that, In step S3, the injection vulcanization molding die also includes a wire pressing block (5). When processing cables (10) of different specifications and arrangements, the cable end positioning block (3) and the wire pressing block (5) with corresponding through holes are replaced to fix the cables (10).

8. The vulcanization molding method for cable connectors as described in claim 1, characterized in that, In step S4, the injection molding mold uses a fast-then-slow injection method, which includes the following two stages: The first stage of glue injection is V1, and the glue injection time t1 is 0.5t; The second stage adhesive injection volume is V2, and the adhesive injection time t2 is 0.5t; Where V1+V2=V; V1>V2; V is the total glue injection volume; t is the total glue injection time; The heating method of step-by-step heating for injection vulcanization molding includes the following three stages: The first stage heating temperature is T1, and the holding time is t3; The second stage heating temperature is T2, and the holding time is t4; The third stage heating temperature is T3, and heating is stopped after holding for t5. Among them, T1 <T2<T3;t3<t4<t5。

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