A cold shrink cable accessory forming device and method

Abstract

The application relates to the cable accessory forming field and particularly discloses a cold-shrink cable accessory forming device and a forming method, which comprises a machine body, an upper die and a lower die arranged on the machine body, a mandrel placed on the lower die and used for forming an inner wall of the cable accessory, a sealing positioning block penetrating through the mandrel and used for supporting and sealing the mandrel after the upper die and the lower die are closed, an extension ring fixed to one end of the sealing positioning block close to the cable accessory, a discharging ring slidably connected to the extension ring, an air passage provided between the extension ring and the discharging ring and connected with an air source, an adjusting mechanism used for adjusting the distance between the end of the sealing positioning block and the end of the discharging ring, a mounting and dismounting mechanism used for separating / assembling the mandrel on the lower die, and a feeding mechanism used for moving the sealing positioning block along the mandrel. The application has the effects of facilitating the discharging of the cold-shrink accessory and reducing the labor degree.

Description

Technical Field

[0001] This application relates to the field of cable accessory molding, and in particular to a cold shrink cable accessory molding apparatus and molding method. Background Technology

[0002] Cold shrink cable accessories are cable connection components made of elastomer materials such as silicone rubber and ethylene propylene rubber as the base material, which are expanded in diameter after injection vulcanization and lined with plastic spiral supports. They belong to the category of cable accessories for normal temperature installation. Cold shrink cable accessories typically include: terminals, joints, stress tubes, insulating tubes, and sealing tubes.

[0003] The manufacturing process of cold-shrink cable accessories (such as cable terminals) is as follows: raw material mixing - vulcanization molding - cable accessory expansion - installation of support core. In the vulcanization molding step, compression molding or injection molding is commonly used. Injection molding typically includes an upper mold, a lower mold, and a mandrel to form the internal hollow structure. During molding, the stress cone is first placed at the designated position on the mandrel. Then, after the mold is closed, liquid silicone rubber, after being metered and mixed, is injected into the mold cavity, and vulcanization is completed at the vulcanization temperature. After vulcanization, the mold is opened and the material is unloaded. Injection molding equipment usually uses a submerged gate, which automatically cuts off the gate material when the mandrel separates from the lower mold. Other waste materials such as flash and sprues are manually trimmed and processed together with the gate material. Once they meet the standards, they can be recycled.

[0004] Regarding the aforementioned technologies, the inventors believe that the following defects exist: Due to the high elasticity, high internal stress, and strong adhesion of silicone rubber cable accessories, the products are tightly attached to the mandrel after vulcanization, making it difficult to separate the cable accessories from the mandrel. Usually, workers need to use high-pressure air pipes to blow air between the cable accessories and the mandrel and simultaneously pull the cable accessories to unload them. The operation is relatively cumbersome and requires a high degree of manual labor. Summary of the Invention

[0005] To address the issues of cumbersome unloading processes and high levels of manual labor, this application provides a cold-shrink cable accessory forming device and forming method.

[0006] The technical solution provided in this application for a cold-shrink cable accessory forming device and forming method is as follows: A cold shrink cable accessory forming device includes a machine body, wherein an upper mold is vertically mounted on the machine body and a lower mold is horizontally movable. A mandrel, placed on the lower mold, is used to form the inner wall of the cable accessory; A sealing positioning block is inserted through the mandrel to support and seal the mandrel after the upper mold and the lower mold are closed. An extension ring is fixedly connected to the end of the sealing positioning block near the cable accessory, and a discharge ring is slidably connected to it from the inside to the outside. A vent is provided between the extension ring and the discharge ring, and an air source is connected to it. The inner circumferential wall of the discharge ring is narrowed from the end near the sealing positioning block to the other end. When the end of the discharge ring is pressed against the sealing positioning block, the vent is blocked. An adjustment mechanism is used to adjust the distance between the end of the sealing positioning block and the end of the unloading ring; A loading and unloading mechanism for separating / assembling the mandrel onto the lower mold; A feeding mechanism is used to push the sealing positioning block to move along the mandrel.

[0007] Optionally, the adjusting mechanism includes an air chamber formed in the sealing positioning block, an air inlet and an air outlet formed in the wall of the air chamber, a main air passage formed in the sealing positioning block, a piston fixed to one end of the unloading ring near the sealing positioning block, and an elastic member formed between the air chamber wall and the piston. The main air passage is connected to the air inlet, and the air passage is connected to the air outlet.

[0008] Optionally, a valve plate is elastically provided in the main air passage and between the air inlet and the air outlet. A stop block adapted to the valve plate is fixedly connected in the main air passage. When the valve plate is in a free state, the valve plate and the stop block are pressed together. When the valve plate and the stop block are separated, the main air passage is connected to the ventilation passage. The diameter of the main air passage is also larger than the diameter of the air inlet.

[0009] Optionally, the valve plate thickness is greater than the diameter of the air inlet, and when the valve plate is separated from the stop block, the valve plate moves to the air inlet.

[0010] Optionally, the loading and unloading mechanism includes a lifting platform that is lifted and lowered on the machine body, a lifting block fixed to the lifting platform, and a connecting block fixed to the end of the mandrel. There are two lifting platforms, which are located on both sides of the lower mold respectively. The lifting block and the connecting block are plugged into each other.

[0011] Optionally, the feeding mechanism includes a dual-axis bracket mounted on the lifting platform and a feeding block mounted on the dual-axis bracket. The bottom of the feeding block is concave and is inserted into and adapted to the sealing positioning block. The running direction of the dual-axis bracket is along the length direction of the spindle and the vertical direction.

[0012] Optionally, both the sealing positioning block and the outer peripheral wall of the unloading ring are provided with annular grooves.

[0013] A method for forming cold-shrink cable accessories includes the following steps: S1. Stress cone installation: Install the stress cone on the unloading ring, and after the sealing positioning block is moved to the designated position by the feeding mechanism, the stress cone is removed by evacuating air through the vent. S2, Mold Closing: Continue to drive the sealing positioning block to the end of the mandrel through the feeding mechanism, and then assemble the mandrel onto the lower mold through the loading and unloading mechanism. Then, drive the lower mold to move directly below the upper mold and lower the upper mold in sequence to close the upper mold and the lower mold. S3, Injection vulcanization molding: The machine is connected to an external material supply source, and the upper and lower molds are kept at a constant vulcanization temperature. The molten rubber is filled and vulcanized in the cavity after the mold is closed. S4. Mold Opening and Unloading: After the vulcanization time is reached, the upper mold and the lower mold are separated. The mandrel and the lower mold are separated by the loading and unloading mechanism. Then, the ventilation channel and the cable accessories are connected by the adjustment mechanism. Gas is injected into the cable accessories through the ventilation channel to separate the cable accessories from the mandrel. The sealing positioning block is pushed by the feeding mechanism to unload the cable accessories from the mandrel.

[0014] In summary, this application includes at least one of the following beneficial technical effects: 1. High-pressure airflow is injected into the venting channel, and the unloading ring is moved on the sealing positioning block by the adjustment mechanism, causing a misalignment between the end of the sealing positioning block and the end of the unloading ring. At this time, the airflow in the venting channel is ejected from the misalignment between the extension ring and the unloading ring. The ejected airflow enters between the cable accessory and the mandrel, separating the adhesion between the cable accessory and the mandrel and avoiding excessive friction caused by the vacuum between the cable accessory and the mandrel. While the venting channel is ventilated, the feeding mechanism pushes the sealing positioning block to move, so that the cable accessory is gradually detached from the mandrel. When the sealing positioning block moves to the end of the mandrel, the cable accessory can be manually pulled off the unloading ring. The unloading process is highly automated, simple, and requires less manual labor. 2. The high-pressure airflow injected from the main air passage enters the air chamber through the air inlet, gradually increasing the gas volume and pressure in the air chamber, which in turn pushes the piston to move. When the piston moves to the air outlet and continues to open the air outlet, airflow is ejected from the air outlet. At the same time, the piston also pushes the unloading ring to move, causing the ends of the unloading ring and the extension ring to misalign. This allows the airflow to enter between the cable accessory and the mandrel from the misalignment. After the cable accessory is completely separated from the mandrel, the air supply to the main air passage is stopped. At this time, the piston returns to its original position due to the elastic force of the elastic element. The gap between the unloading ring and the extension ring closes again, and the gap between the end of the unloading ring and the end of the sealing positioning block also closes, so as to facilitate the next vulcanization molding operation and prevent rubber material from entering the air passage. 3. When the stress cone needs to be installed, air is supplied between the stress cone and the mandrel through the air passage, and the stress cone is moved by the feeding mechanism. When the stress cone moves to the designated position, the air source instantly switches from blowing to sucking. Due to the large volume of the air chamber and the small diameter of the air inlet, it is difficult for a large amount of gas in the air chamber to be extracted from the air inlet quickly and instantly, causing the gas to push open the valve plate. The movement of the valve plate blocks part or even all of the air inlet, further reducing the outflow of gas in the air chamber. At this time, the piston's reset degree is limited, and there is still a gap between the extension ring and the unloading ring to allow the airflow to pass smoothly. This creates a vacuum between the stress cone and the mandrel, greatly increasing the friction between the mandrel and the stress cone. As the feeding mechanism drives the sealing positioning block to move continuously, the stress cone gradually disengages from the unloading ring to achieve the installation of the stress cone and reduce the degree of manual intervention during the stress cone installation process. 4. During the vulcanization process, the two annular grooves create two retaining rings on the cable accessory. When the unloading ring and the sealing positioning block move relative to each other, the annular groove on the sealing positioning block hooks onto the retaining ring of the cable accessory, and the corresponding retaining ring of the cable accessory on the unloading ring engages in the gap created by the relative movement of the unloading ring and the sealing positioning block. The two retaining rings prevent airflow from leaking from the end of the cable accessory near the sealing positioning block, and also prevent excessive airflow from blowing the end of the cable accessory near the sealing positioning block over. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the overall structure of an embodiment of this application; Figure 2 This is a structural diagram of the application after concealing the upper mold and the feeding mechanism; Figure 3 This application is mainly used to show the cross-sectional structural schematic diagram of the lower mold, sealing positioning block, extension ring, unloading ring, venting channel, annular groove, adjustment mechanism and cold shrink accessories during the vulcanization molding process; Figure 4 yes Figure 3 An enlarged schematic diagram of part A in the middle.

[0016] Reference numerals: 1. Machine body; 11. Upper mold; 12. Lower mold; 13. Mandrel; 2. Sealing and positioning block; 21. Extension ring; 22. Unloading ring; 23. Vent passage; 24. Annular groove; 3. Adjustment mechanism; 31. Air chamber; 32. Air inlet; 33. Air outlet; 34. Main air passage; 35. Piston; 36. Elastic element; 41. Valve plate; 42. Stop block; 5. Loading and unloading mechanism; 51. Lifting platform; 52. Lifting block; 53. Connecting block; 6. Feeding mechanism; 61. Dual-axis bracket; 62. Feeding block; 7. Cold shrink accessory. Detailed Implementation

[0017] The following is in conjunction with the appendix Figure 1-4This application will be described in further detail.

[0018] Example 1 This application discloses a cold-shrink cable accessory forming apparatus. (Refer to...) Figures 1-4 The cold shrink cable accessory forming device includes a body 1, an upper mold 11 that is raised and lowered and a lower mold 12 that is moved horizontally. Multiple hydraulic cylinders are installed between the body 1 and the upper mold 11, and between the body 1 and the lower mold 12. The movement of the upper mold 11 and the lower mold 12 is driven by the hydraulic cylinders connected to them. A mandrel 13 is placed on the lower mold 12 and is used to form the inner wall of the cable accessory 7. A sealing positioning block 2 passes through the mandrel 13. During the closing process of the upper mold 11, mandrel 13, and lower mold 12, the sealing positioning block 2 facilitates the guidance of the mandrel 13 to the corresponding positions on the upper mold 11 and lower mold 12. In the cavity of the mold, after the upper mold 11 and lower mold 12 are closed, the mandrel 13 is supported and sealed by the sealing positioning block 2 to prevent the glue from overflowing from the gap between the mandrel 13 and the upper mold 11 and lower mold 12. The sealing positioning block 2, near the end of the cable accessory 7, has an extension ring 21 integrally formed from the inside to the outside and a stripper ring 22 slidably connected thereto. A vent 23 with an external air source is provided between the extension ring 21 and the stripper ring 22. The inner peripheral wall of the stripper ring 22 is narrowed from the end near the sealing positioning block 2 to the other end. When the end of the stripper ring 22 abuts against the sealing positioning block 2, the vent 23 is blocked. This application also includes an adjustment mechanism 3 for adjusting the distance between the end of the sealing positioning block 2 and the end of the stripper ring 22; a loading and unloading mechanism 5 for separating / assembling the mandrel 13 onto the lower mold 12; and a feeding mechanism 6 for pushing the sealing positioning block 2 to move along the mandrel 13.

[0019] The stress cone is placed at the corresponding position on the mandrel 13. The mandrel 13 is then assembled onto the lower mold 12 via the loading and unloading mechanism 5. The lower mold 12 is then moved below the upper mold 11, and the upper mold 11 is lowered until it is pressed against the lower mold 12, completing the mold closing. Material is then fed to the machine body 1, and the upper mold 11 and lower mold 12 are heated to vulcanize and mold the rubber. After the cable accessory 7 is molded, the upper mold 11 is raised and the lower mold 12 is moved horizontally to a position that is easy for the staff to observe and operate. Then, the loading and unloading mechanism 5 raises the mandrel 13, separating the mandrel 13 from the lower mold 12. At this point, unloading can begin. Specifically, high-pressure airflow is injected into the ventilation channel 23, and the unloading ring 22 is moved on the sealing positioning block 2 by the adjusting mechanism 3, causing a misalignment between the end of the sealing positioning block 2 and the end of the unloading ring 22. At this time, the airflow in the ventilation channel 23 is ejected from the misalignment between the extension ring 21 and the unloading ring 22. The ejected airflow enters between the cable accessory 7 and the spindle 13, separating the adhesion between the cable accessory 7 and the spindle 13 and preventing excessive friction between the two due to the vacuum between the cable accessory 7 and the spindle 13. While the ventilation channel 23 is ventilated, the feeding mechanism 6 pushes the sealing positioning block 2 to move, causing the cable accessory 7 to gradually detach from the spindle 13 until the sealing positioning block 2 moves to the end of the spindle 13. Then, the cable accessory 7 can be manually pulled off the unloading ring 22. The unloading process is highly automated, simple, and requires less manual labor. After unloading, the cable accessory 7 can be finely repaired.

[0020] Reference Figure 3 and Figure 4 The adjusting mechanism 3 includes an air chamber 31 formed within the sealing positioning block 2, an air inlet 32 ​​and an air outlet 33 formed within the wall of the air chamber 31, a main air passage 34 formed within the sealing positioning block 2, a piston 35 fixed to one end of the unloading ring 22 near the sealing positioning block 2, and an elastic element 36 formed between the wall of the air chamber 31 and the piston 35. The elastic element 36 can be an elastic gasket or a spring. The main air passage 34 is connected to the air inlet 32, and the air passage 23 is connected to the air outlet 33. The air chamber 31 and the air passage 24 are connected to the main air passage 34. All three are circular in shape with the spindle 13 as the axis. Multiple air outlets 33 are evenly distributed on the peripheral wall of the air chamber 31, so that the ventilation channel 23 is indirectly connected to the external air source through the main air channel 34. The multiple air outlets 33 make the airflow ejected from the ventilation channel 23 more uniform in the circumferential direction, avoiding the cable accessory 7 from receiving excessive airflow in some areas while other areas receive little or no airflow. The air source can be a blower and suction pump, such as a fast-responding diaphragm pump, or it can be connected to a blower pump and a suction pump through a three-way pipe. The outer peripheral wall of the sealing positioning block 2 and the unloading ring 22 are both provided with annular grooves 24. The annular grooves 24 are inclined at one end facing the unloading direction of the cable accessory 7 and vertical at the other end.

[0021] During the vulcanization process, the two annular grooves 24 create two retaining rings on the cable accessory 7. High-pressure airflow injected from the main air passage 34 enters the air chamber 31 through the air inlet 32, gradually increasing the gas volume and pressure within the chamber. This drives the piston 35 to move. When the piston 35 moves to the air outlet 33 and continues to open it, airflow is ejected from the outlet 33. Simultaneously, the piston 35 also pushes the unloading ring 22 to move, causing misalignment between the ends of the unloading ring 22 and the extension ring 21. This allows airflow to enter between the cable accessory 7 and the mandrel 13 from the misaligned area. During this process, the annular grooves 24 on the sealing positioning block 2 hook onto the retaining rings of the cable accessory 7, and the annular grooves on the unloading ring 22... The corresponding cable accessory 7 retainer is engaged in the gap created by the relative movement of the unloading ring 22 and the sealing positioning block 2. The two retainers prevent airflow from leaking from the end of the cable accessory 7 near the sealing positioning block 2, and also prevent excessive airflow from blowing the end of the cable accessory 7 near the sealing positioning block 2 over. After the cable accessory 7 is completely separated from the mandrel 13, the air supply to the main air passage 34 is stopped. At this time, the piston 35 is reset due to the elastic force of the elastic element 36, and the gap between the unloading ring 22 and the extension ring 21 is closed again. The gap between the end of the unloading ring 22 and the end of the sealing positioning block 2 is also closed to facilitate the next vulcanization molding operation and prevent the rubber material from entering the air passage 23.

[0022] Reference Figure 3 and Figure 4 A valve plate 41 is elastically provided inside the main air passage 34 and between the air inlet 32 ​​and the air outlet 33. The valve plate 41 can also be connected to the inner wall of the main air passage 34 by an elastic washer or spring. A stop block 42 adapted to the valve plate 41 is fixed inside the main air passage 34. When the valve plate 41 is in a free state, the valve plate 41 and the stop block 42 are pressed together. When the valve plate 41 and the stop block 42 are separated, the main air passage 34 and the air passage 23 can be connected to the air outlet 33 without the air inlet 32. The diameter of the main air passage 34 is also larger than the diameter of the air inlet 32. The thickness of the valve plate 41 is larger than the diameter of the air inlet 32. When the valve plate 41 and the stop block 42 are separated, the valve plate 41 moves to the air inlet 32. When the end of the unloading ring 22 is pressed together with the end of the sealing positioning block 2, the end of the piston 35 near the sealing positioning block 2 is far from the air outlet 33.

[0023] When the stress cone needs to be installed, first open one end of the stress cone and put the opened end on the unloading ring 22. Air is supplied between the stress cone and the mandrel 13 through the air passage 23, and the stress cone is moved by the feeding mechanism 6. When the stress cone moves to the designated position, the air source instantly changes from blowing to sucking. Although the piston 35 returns to its original position to a certain extent due to the action of the elastic element 36 and the reduction of gas in the air chamber 31, the air in the air chamber 31 is large in volume and the air inlet 32 ​​has a small diameter, so the gas in the air chamber 31 cannot be quickly and massively drawn out instantly. The gas is drawn out from port 32, causing more gas to push open valve plate 41. The movement of valve plate 41 then blocks part or all of the gas inlet 32, further reducing the outflow of gas from the gas chamber 31. At this point, the piston 35 has a limited degree of reset, and a gap still exists between the extension ring 21 and the unloading ring 22, allowing airflow to pass smoothly. This creates a vacuum between the stress cone and the mandrel 13, greatly increasing the friction between the mandrel 13 and the stress cone. As the feeding mechanism 6 drives the sealing positioning block 2 to move continuously, the stress cone gradually disengages from the unloading ring 22, thus achieving the installation of the stress cone. After the stress cone disengages from the unloading ring 22, the gas source stops pumping, valve plate 41 resets, and the gas inlet 32, freed from the obstruction of valve plate 41, begins to exhaust gas in conjunction with the reset of piston 35, until the gap between the unloading ring 22 and the extension ring 21 disappears. The entire installation process of the stress cone is relatively simple, requires less manual intervention, and the installation position of the stress cone can be controlled simply by controlling the pumping period of the gas source.

[0024] If the staff finds that the installation position error of the stress cone is large or that it is difficult to quickly evacuate the stress cone and the mandrel 13, it is necessary to replace it with a gas source with a faster response speed. Alternatively, the extension ring 21 can be replaced, and a one-way valve can be installed at the outlet 33 of the new extension ring 21 so that the outlet 33 only allows the gas in the air chamber 31 to be discharged and prevents the gas from entering the air chamber 31 from the outlet 33.

[0025] Reference Figure 2 and Figure 3 The loading and unloading mechanism 5 includes a lifting platform 51 mounted on the machine body 1, a lifting block 52 fixed on the lifting platform 51, and a connecting block 53 fixed to the end of the mandrel 13. There are two lifting platforms 51, which are located on both sides of the lower mold 12. The lifting block 52 and the connecting block 53 are plugged into each other. This application is a three-station device, that is, three mandrels 13 are placed on one lower mold 12, and one connecting block 53 connects all the mandrels 13.

[0026] When it is necessary to separate the mandrel 13 from the lower mold 12, move the lower mold 12 to the lifting platform 51, and then raise the lifting platform 51 so that the lifting block 52 is inserted into the connecting block 53 and the connecting block 53 is raised. At this time, the mandrel 13 is separated from the lower mold 12, and there is no need to manually remove the mandrel 13.

[0027] Reference Figure 1and Figure 2 The feeding mechanism 6 includes a dual-axis bracket 61 mounted on the lifting platform 51 and a feeding block 62 mounted on the dual-axis bracket 61. The bottom of the feeding block 62 is concave and is inserted into and adapted to the sealing positioning block 2. The running direction of the dual-axis bracket 61 is along the length of the spindle 13 and vertically. The dual-axis bracket 61 is also hydraulically or pneumatically driven. When it is necessary to move the sealing positioning block 2, the feeding block 62 is driven to the sealing positioning block 2 by the dual-axis bracket 61 and inserted into the sealing positioning block 2. At this time, the sealing positioning block 2 can continue to be moved horizontally by the dual-axis bracket 61. The structure is simple and easy to maintain, and there is no need to manually move the sealing positioning blocks 2 one by one.

[0028] The implementation principle of the cold shrink cable accessory molding device and molding method in this application embodiment is as follows: First, one end of the stress cone is spread open and placed on the unloading ring 22. Air is supplied between the stress cone and the mandrel 13 through the air passage 23, and the stress cone is moved by the feeding mechanism 6. When the stress cone moves to the designated position, the air source instantly changes from blowing to sucking. The gas in the air chamber 31 is difficult to be quickly and massively extracted from the air inlet 32, causing the valve plate 41 to be pushed open. The movement of the valve plate 41 blocks part or even all of the air inlet 32, further reducing the outflow of gas in the air chamber 31. This limits the degree of piston 35 reset, thus leaving a gap between the extension ring 21 and the unloading ring 22 to allow airflow to pass smoothly, facilitating the vacuuming between the stress cone and the mandrel 13. As the feeding mechanism 6 drives the sealing positioning block 2 to move continuously, the stress cone gradually disengages from the unloading ring 22, thus achieving the installation of the stress cone.

[0029] After the stress cone detaches from the unloading ring 22, the air source stops sucking, the valve plate 41 resets, and the air inlet 32 ​​disengages from the obstruction of the valve plate 41 and starts to exhaust air in conjunction with the reset of the piston 35 until the gap between the unloading ring 22 and the extension ring 21 disappears. Then, the mandrel 13 is assembled onto the lower mold 12 through the loading and unloading mechanism 5, the lower mold 12 is driven to be directly below the upper mold 11, and then the upper mold 11 is lowered to complete the mold closing. Then, the material is fed to the machine body 1, and the upper mold 11 and the lower mold 12 are heated to vulcanize the rubber material. During the vulcanization process, the two annular grooves 24 cause two retaining rings to be generated on the cable accessory 7.

[0030] After the cable accessory 7 is formed, the upper mold 11 is raised and the lower mold 12 is moved to a position that is easy for the staff to observe and operate. Then, the loading and unloading mechanism 5 raises the mandrel 13. The high-pressure airflow injected from the main air passage 34 enters the air chamber 31 through the air inlet 32, which gradually increases the gas volume and pressure in the air chamber 31, thereby pushing the piston 35 to move. When the piston 35 moves to the air outlet 33 and continues to open the air outlet 33, the air outlet 33 ejects airflow. At the same time, the piston 35 also pushes the unloading ring 22 to move, causing the end of the unloading ring 22 to misalign with the end of the extension ring 21. The airflow enters between the cable accessory 7 and the spindle 13 from the misalignment, separating the adhesion between the cable accessory 7 and the spindle 13 and preventing excessive friction caused by the vacuum between the cable accessory 7 and the spindle 13. While the air passage 23 is ventilated, the feeding mechanism 6 pushes the sealing positioning block 2 to move, so that the cable accessory 7 gradually detaches from the spindle 13. When the sealing positioning block 2 moves to the end of the spindle 13, the cable accessory 7 can be manually pulled off the unloading ring 22. The unloading is highly automated, the unloading process is simple, and the degree of manual labor is low.

[0031] Example 2 This application discloses a method for molding cold-shrink cable accessories, referring to... Figures 1-3 The forming method for cold-shrink cable accessory 7 includes the following steps: S1. Stress cone installation: Install the stress cone on the unloading ring 22, and after the sealing positioning block 2 is moved to the designated position by the feeding mechanism 6, the stress cone is removed by evacuating air through the vent 23. S2, Mold closing: Continue to drive the sealing positioning block 2 to the end of the mandrel 13 through the feeding mechanism 6, and then assemble the mandrel 13 onto the lower mold 12 through the loading and unloading mechanism 5. Then drive the lower mold 12 to move directly below the upper mold 11 and lower the upper mold 11 so that the upper mold 11 and the lower mold 12 can close the mold. S3, Injection vulcanization molding: The machine body 1 is connected to an external material supply source, and the upper mold 11 and lower mold 12 are kept at a constant vulcanization temperature. The molten rubber is filled and vulcanized in the cavity after the mold is closed. S4. Mold opening and unloading: After the vulcanization time is reached, the upper mold 11 and the lower mold 12 are separated. The mandrel 13 and the lower mold 12 are separated by the loading and unloading mechanism 5. Then, the ventilation channel 23 is connected to the cable accessory 7 by the adjusting mechanism 3. Gas is injected into the cable accessory 7 through the ventilation channel 23 to separate the cable accessory 7 from the mandrel 13. The sealing positioning block 2 is pushed by the feeding mechanism 6 to unload the cable accessory 7 from the mandrel 13.

[0032] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A cold-shrink cable accessory forming device, characterized in that, include: The machine body (1) is provided with an upper mold (11) that is raised and lowered and a lower mold (12) that is moved horizontally. The mandrel (13) is placed on the lower mold (12) for forming the inner wall of the cable accessory (7); A sealing positioning block (2) is installed on the mandrel (13) to support and seal the mandrel (13) after the upper mold (11) and the lower mold (12) are closed. An extension ring (21) is fixedly connected to the end of the sealing positioning block (2) from the inside to the outside, and a discharge ring (22) is slidably connected to it. An air passage (23) with an external air source is provided between the extension ring (21) and the discharge ring (22). The inner circumferential wall of the discharge ring (22) is narrowed from the end near the sealing positioning block (2) to the other end. When the end of the discharge ring (22) abuts against the sealing positioning block (2), the air passage (23) is blocked. Adjustment mechanism (3) is used to adjust the distance between the end of the sealing positioning block (2) and the end of the unloading ring (22); The loading and unloading mechanism (5) is used to separate / assemble the mandrel (13) onto the lower mold (12); The feeding mechanism (6) is used to push the sealing positioning block (2) to move along the spindle (13); The adjustment mechanism (3) includes an air chamber (31) opened in the sealing positioning block (2), an air inlet (32) and an air outlet (33) opened in the wall of the air chamber (31), a main air passage (34) set in the sealing positioning block (2), a piston (35) fixed to the unloading ring (22) near the end of the sealing positioning block (2), and an elastic member (36) set between the wall of the air chamber (31) and the piston (35). The main air passage (34) is connected to the air inlet (32), and the air passage (23) is connected to the air outlet (33). A valve plate (41) is elastically provided in the main air passage (34) and between the air inlet (32) and the air outlet (33). A stop block (42) adapted to the valve plate (41) is fixedly connected in the main air passage (34). When the valve plate (41) is in a free state, the valve plate (41) and the stop block (42) are pressed together. When the valve plate (41) and the stop block (42) are separated, the main air passage (34) is connected to the ventilation passage (23). The aperture of the main air passage (34) is also larger than the aperture of the air inlet (32).

2. The cold shrink cable accessory forming device according to claim 1, characterized in that: The thickness of the valve plate (41) is greater than the diameter of the air inlet (32). When the valve plate (41) is separated from the stop block (42), the valve plate (41) moves to the air inlet (32).

3. The cold shrink cable accessory forming device according to claim 1, characterized in that: The loading and unloading mechanism (5) includes a lifting platform (51) that is lifted and lowered on the machine body (1), a lifting block (52) fixed on the lifting platform (51), and a connecting block (53) fixed on the end of the spindle (13). There are two lifting platforms (51) and they are located on both sides of the lower mold (12). The lifting block (52) and the connecting block (53) are plugged into each other.

4. The cold shrink cable accessory forming device according to claim 3, characterized in that: The feeding mechanism (6) includes a double-axis bracket (61) set on the lifting platform (51) and a feeding block (62) set on the double-axis bracket (61). The bottom of the feeding block (62) is concave and is inserted into and adapted to the sealing positioning block (2). The running direction of the double-axis bracket (61) is along the length direction of the spindle (13) and the vertical direction.

5. The cold shrink cable accessory forming device according to claim 1, characterized in that: Both the sealing positioning block (2) and the unloading ring (22) have annular grooves (24) on their outer peripheral walls.

6. A method for forming cold-shrink cable accessories, based on the cold-shrink cable accessory forming apparatus according to any one of claims 1-5, characterized in that, The steps include the following: S1. Stress cone installation: Install the stress cone on the unloading ring (22), and drive the sealing positioning block (2) to move to the designated position through the feeding mechanism (6), and then remove the stress cone by evacuating through the vent (23); S2, Mold closing: Continue to drive the sealing positioning block (2) to the end of the mandrel (13) through the feeding mechanism (6), and then assemble the mandrel (13) onto the lower mold (12) through the loading and unloading mechanism (5). Then drive the lower mold (12) to move directly below the upper mold (11) and lower the upper mold (11) so that the upper mold (11) and the lower mold (12) can close the mold. S3, Injection vulcanization molding: The machine body (1) is connected to an external material supply source, and the upper mold (11) and lower mold (12) are kept at a constant vulcanization temperature. The molten rubber is filled and vulcanized in the cavity after the mold is closed. S4. Mold opening and unloading: After the vulcanization time is reached, the upper mold (11) and the lower mold (12) are separated. The mandrel (13) and the lower mold (12) are separated by the loading and unloading mechanism (5). The ventilation channel (23) and the cable accessory (7) are connected by the adjustment mechanism (3). Gas is injected into the cable accessory (7) through the ventilation channel (23) to separate the cable accessory (7) from the mandrel (13). The sealing positioning block (2) is pushed by the feeding mechanism (6) so that the cable accessory (7) is unloaded from the mandrel (13).

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