An underwater plug-in connector

Abstract

The application relates to an underwater plug connector, which comprises an outer shell, an outer balance capsule and a hole insulator, an insulating bushing is sleeved on the front end outer wall of the outer balance capsule, an insulating pressing plate is arranged in the inner part of the outer balance capsule, at least one jack contact assembly is arranged between the insulating pressing plate and the hole insulator, the jack contact assembly is used for pressing the insulating pressing plate against the inner wall front end surface of the outer balance capsule, the insulating bushing is used for axially positioning the outer balance capsule, a first contact piece hole position is arranged on the front end part of the outer balance capsule, a second contact piece hole position corresponding to the first contact piece hole position is arranged on the insulating pressing plate, a protrusion close to the second contact piece hole position is arranged on the front end of the insulating pressing plate, and a groove matched with the protrusion is arranged on the inner wall front end surface of the outer balance capsule. The application can reduce the position degree deviation of the contact piece hole position caused by the axial extrusion deformation of the outer balance capsule, and the eccentricity caused by the axial extrusion deformation and the radial interference deformation at each contact piece hole position can be reduced through the cooperation of the protrusion and the groove.

Description

Technical Field

[0001] This invention belongs to the field of watertight connector technology, and specifically relates to an underwater pluggable connector. Background Technology

[0002] Underwater wet-plug connectors are widely used in seabed observation networks and deep-sea oil and gas development, primarily for power and signal transmission between deep-sea devices, requiring the ability to be plugged in and out in deep-sea environments. The deep sea is a high-pressure environment, with pressure increasing by approximately 1 MPa per 100 meters of depth, posing a significant challenge to the sealing of the devices. Therefore, a pressure-balancing structure is needed to reduce the pressure difference between the inside and outside of the electrical connector device. The main principle of pressure-balancing technology is based on the compressibility of liquids; by changing the volume of the sealed cavity, the internal liquid is compressed, thereby increasing the internal pressure of the sealed cavity. Currently, research on pressure-balanced plug-in connectors in China is still in its early stages, and there are relatively few manufacturers capable of developing and producing this type of connector.

[0003] Existing pressure-balanced wet-mating electrical connectors are generally axially fixed and assembled by an insulator end cap, an outer balance chamber, and an insulating pressure plate arranged sequentially from front to back inside the connector housing. This ensures the sealing of the overall connector structure and the realization of the mating and unmating functions. The connector housing contains a socket contact assembly. Each of these three components—the insulator end cap, the outer balance chamber, and the insulating pressure plate—must have contact holes for the pins of the adapter connector to insert into. When the connector is not mated, the contact holes are sealed by a movable push rod axially positioned within the socket contact assembly to prevent external liquids from entering the inner balance chamber of the socket contact assembly. When the connector is mated, the pins of the adapter connector push the movable push rod into the contact holes, further establishing electrical communication with the socket contact assembly. The structure has the following disadvantages: (1) The contact holes on the three parts, namely the insulator end cap, the outer balance bladder and the insulating pressure plate, must be kept concentric. The coaxiality of the contact holes is very high, the processing accuracy is very high, and the processing is difficult. (2) After the outer balance bladder is axially squeezed between the insulator end cap and the insulating pressure plate, the corresponding contact holes on the three parts are not concentric. This makes it easy for the movable push rod to not rebound in time after the product is inserted or removed, resulting in water entering the balance bladder inside the product and affecting the product's lifespan. Summary of the Invention

[0004] To address the technical problems existing in the prior art, the present invention provides an underwater pluggable connector.

[0005] The objective of this invention and the technical problem it solves are achieved by the following technical solution. According to this invention, an underwater pluggable connector includes a housing, an outer balancing bladder, and a mounting insulator disposed within the housing. An annular insulating bushing is fitted onto the outer wall of the front end of the outer balancing bladder. An insulating pressure plate is disposed inside the outer balancing bladder. At least one pluggable contact assembly is provided between the insulating pressure plate and the mounting insulator. The pluggable contact assembly is used to axially press the insulating pressure plate forward against the front end face of the inner wall of the outer balancing bladder. The insulating bushing is fixed within the housing and used for axial positioning of the outer balancing bladder. A first contact hole is provided at the front end of the outer balancing bladder. A second contact hole corresponding to the first contact hole is provided on the insulating pressure plate. A protrusion is provided at the front end of the insulating pressure plate near the second contact hole. A groove cooperating with the protrusion is provided on the front end face of the inner wall of the outer balancing bladder.

[0006] The beneficial effects are as follows: This invention uses a ring-shaped insulating bushing, while the prior art uses a plate-shaped insulating bushing end cap covering the front end of the outer balance bladder. Therefore, compared with the prior art, the insulating bushing in this invention is changed from the entire axial plane extrusion method in the prior art to circumferential extrusion, avoiding the influence of hole eccentricity caused by the insulating bushing during connector mating, and effectively reducing the positional deviation of the contact hole caused by axial extrusion deformation of the outer balance bladder. Furthermore, the insulating pressure plate adds a protrusion at the front end of each contact hole, and the outer balance bladder adds a groove at the corresponding position. The cooperation between the protrusion and the groove helps to reduce the eccentricity caused by axial extrusion deformation and radial interference deformation at each contact hole.

[0007] Furthermore, the rear end of the insulating bushing has a limiting surface, and the outer side of the front end of the outer balance bag has a circumferentially extending stepped surface. The limiting surface and the stepped surface are axially stopped to restrict the forward movement of the outer balance bag.

[0008] Furthermore, the second contact hole has multiple protrusions, which are arranged in a ring array around the second contact hole.

[0009] Furthermore, the rear end of the external balancing bladder is sealed to the front outer wall of the perforated insulator.

[0010] Furthermore, the socket contact assembly includes a socket contact element, an inner balancing bladder, a movable push rod, and a conductive rod. The inner balancing bladder is fitted onto the outside of the socket contact element, and its front end is inserted into the insertion hole at the rear end of the insulating pressure plate. The movable push rod is slidably disposed within the socket contact element in the front-back direction. The conductive rod is connected to the rear end of the socket contact element. An elastic element is provided between the movable push rod and the conductive rod. The elastic element provides a forward pushing force to the movable push rod so that it closes the corresponding first and second contact hole positions when the connector is not inserted. The outer balancing bladder, the insulating pressure plate, and the socket insulator form a sealed cavity filled with pressure balancing fluid. The inner balancing bladder is located in the sealed cavity, and there is a deformation space between the outer balancing bladder and the outer shell.

[0011] Furthermore, the outer wall of the movable push rod is provided with a flange, which is used to axially stop and cooperate with the limiting platform provided on the inner wall of the insertion hole contact to prevent the movable push rod from dislodging forward from the insertion hole contact.

[0012] Furthermore, the front end of the socket contact is provided with an elastic inner sleeve for elastic contact and conduction with the pins of the adapter connector. The front end of the socket contact is also provided with an outer sleeve fitted on the elastic inner sleeve. The outer sleeve is used to radially support the front opening of the inner balance bladder. The socket contact pushes the inner balance bladder forward through the outer sleeve so that the inner balance bladder contacts and engages with the insulating pressure plate.

[0013] Furthermore, the conductive rod is threadedly connected to the socket contact to seal the rear end opening of the socket contact, the rear end of the inner balance bladder is sealed to the conductive rod, and the rear end of the conductive rod has a terminal that extends backward through the socket insulator.

[0014] Furthermore, at least one annular sealing protrusion is provided on the inner wall of the first contact hole, and at least one annular sealing protrusion is also provided on the inner wall of the front opening of the inner balance bladder that slides and seals with the movable push rod.

[0015] Furthermore, a retaining ring is embedded in the inner wall of the front end of the outer casing. The retaining ring is axially stopped by the insulating bushing to restrict the forward movement of the insulating bushing.

[0016] Furthermore, the movable push rod is made of PEEK material with self-lubricating function. The beneficial effect is that, since the movable push rod and the outer balance bladder achieve a dynamic seal through radial interference fit, after insertion and removal, in order to reduce the friction between the movable push rod and the outer balance bladder, the use of PEEK material with self-lubricating function for the movable push rod can reduce the coefficient of friction between the movable push rod and the outer balance bladder, which is beneficial for the smooth rebound of the movable push rod after the connector is inserted and removed.

[0017] By employing the above technical solution, the present invention has at least the following advantages compared with the prior art:

[0018] 1. The present invention changes the end cap structure of the front insulator to an insulating bushing structure, and changes the axial plane extrusion of the front end of the outer balance bladder to the circumferential extrusion of the outer wall, which can greatly reduce the positional deviation of the contact hole caused by the axial extrusion deformation of the outer balance bladder.

[0019] 2. In this invention, the insulating pressure plate has a protrusion at the front end of each contact hole, and the outer balance bladder has a groove at the corresponding position. The protrusion of the insulating pressure plate and the groove of the outer balance bladder cooperate to reduce the eccentricity caused by axial compression deformation and radial interference deformation at each contact hole, and further improve and maintain the coaxiality of the corresponding contact holes on the insulating pressure plate and the outer balance bladder.

[0020] 3. Since the movable push rod and the outer balance bladder achieve dynamic sealing through radial interference fit, in order to reduce the friction between the movable push rod and the outer balance bladder after insertion and removal, the movable push rod material in this invention is selected to have self-lubricating function PEEK, which can reduce the friction coefficient between the movable push rod and the outer balance bladder, and facilitate the smooth rebound of the movable push rod after the connector is inserted and separated.

[0021] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described in detail below with reference to the accompanying drawings. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the internal structure of an underwater pluggable connector according to the present invention.

[0023] Figure 2 This is a partially enlarged cross-sectional schematic diagram of an underwater pluggable connector according to the present invention.

[0024] Figure 3 This is a partial cross-sectional structural diagram of the external balance bladder in this invention.

[0025] Figure 4 This is a cross-sectional structural diagram of the insulating pressure plate in this invention.

[0026] Figure 5 This is a cross-sectional view of an underwater pluggable connector according to the present invention.

[0027] The markings in the diagram are: 1-outer shell, 2-insulating bushing, 3-outer balance bladder, 4-insulating pressure plate, 5-insulating body with mounting hole, 6-socket contact assembly, 7-retaining ring, 8-sealing cavity, 9-deformation space, 11-limiting boss, 12-drain hole, 21-limiting surface, 30-front end, 31-step surface, 32-first contact hole, 321-annular sealing protrusion, 33-front end face of inner wall, 34-groove, 35-inner convex sealing platform, 41-second contact hole, 42-protrusion, 51-sealing positioning groove, 61-socket contact, 62-inner balance bladder, 63-movable top rod, 64-conductive rod, 65-elastic element, 66-gap, 67-internal space, 68-elastic inner sleeve, 69-outer sleeve, 611-limiting platform, 621-front opening, 631-flange, 6311-through groove, 641-sealing ring. Detailed Implementation

[0028] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and preferred embodiments.

[0029] In the description of this invention, it should be understood that the terms "center", "upper", "lower", "front", "rear", "vertical", "horizontal", "top", "bottom", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0030] like Figures 1 to 5As shown, an underwater pluggable connector includes a housing 1, an insulating bushing 2, an outer balancing bladder 3, an insulating pressure plate 4, a mounting insulator 5, and a socket contact assembly 6. The front end of the underwater pluggable connector is the end that mates with the adapter connector. The outer balancing bladder 3 is installed inside the housing 1, and its outer peripheral surface, which is in interference contact with the housing 1, serves as a sealing surface to prevent external liquids from entering the housing 1 through the contact surface. The insulating bushing 2 is fitted onto the outer wall of the front end of the outer balancing bladder 3. A retaining ring 7 is embedded in the inner wall of the front end of the housing 1, and the retaining ring 7 and the insulating bushing 2 engage in a forward-moving stop to restrict the forward movement of the insulating bushing. A limiting surface 21 is provided at the rear end of the insulating bushing 2, and a stepped surface 31 is provided at the front end 30 of the outer balancing bladder 3. The stepped surface 31 extends circumferentially along the outer side of the front end 30 of the outer balancing bladder, and the limiting surface 21 and the stepped surface 31 engage axially to restrict the forward movement of the outer balancing bladder. The insulating bushing 2 is radially positioned between the housing 1 and the outer balancing bladder 3, and is located inside the front end of the housing 1. In this invention, the insulating bushing 2 is integrally fitted onto the outside of the outer balance bladder 3. Through the cooperation of the circumferentially extending limiting surface and the stepped surface, the axial planar compression of the entire front end face of the outer balance bladder by the insulator end cap in the prior art is improved to the circumferential compression at the outer edge of the outer balance bladder. This can greatly reduce the positional deviation of the corresponding contact hole positions caused by the axial compression deformation of the outer balance bladder. Furthermore, since the annular insulating bushing no longer completely covers the front end face of the outer balance bladder, there is no corresponding contact hole position on the insulating bushing that corresponds to the first contact hole position 32 on the outer balance bladder. Compared with the prior art, where corresponding, connected, and coaxial contact holes need to be provided on all three parts (insulator end cap, outer balance bladder, and insulating pressure plate), the technical solution of this invention directly eliminates the contact hole positions on the insulating bushing, thereby reducing the probability of misalignment of the corresponding contact holes on different parts during insertion and removal.

[0031] An insulating pressure plate 4 is disposed inside the outer balancing bladder 3. It not only radially supports the outer balancing bladder, maintaining the structural strength of its front end and ensuring tight contact between the bladder and the outer shell to improve sealing, but also enhances the structural strength of the connector's insertion point, allowing the front end of the outer balancing bladder to meet the requirements for repeated underwater insertion and removal. Furthermore, the insulating pressure plate presses the outer balancing bladder forward against the rear end of the insulating bushing. A socket contact assembly 6 is mounted on a socket insulator 5, which is installed inside the outer shell 1. The inner wall of the outer shell 1 has a limiting boss 11 that axially limits the socket insulator to prevent it from retracting. The front end of the socket contact assembly is connected to the insulating pressure plate, and the socket contact assembly axially presses the insulating pressure plate 4 forward against the front end face 33 of the inner wall of the outer balancing bladder 3 to achieve axial positioning of the insulating pressure plate, while simultaneously axially pressing the outer balancing bladder against the rear end of the insulating bushing to achieve axial fixation of the outer balancing bladder. The insulating pressure plate 4 is provided with a second contact hole 41, which is coaxial with the corresponding first contact hole 32. The front end of the insulating pressure plate 4 is provided with an axially extending protrusion 42, which is located close to the second contact hole 41. When there are multiple socket contact assemblies 6, the second contact holes 41 are also provided in the same number. Thus, the front end of the insulating pressure plate 4 is provided with a protrusion 42 at each second contact hole. Preferably, there are multiple protrusions at each second contact hole, and the multiple protrusions are distributed circumferentially or in a ring array around the second contact hole. The protrusion 42 can be columnar, plate-shaped, etc., and the present invention does not limit this. The outer balance bladder 3 has a groove 34 on the inner wall front surface 33 facing the front end of the insulating pressure plate, which corresponds to the protrusion. The groove is also adjacent to each first contact hole. The groove of the outer balance bladder and the protrusion of the insulating pressure plate are in a concave-convex fit, so that the outer balance bladder and the insulating pressure plate are in a radial upper limit fit, which effectively restricts the radial offset between the two. This helps to reduce the eccentricity caused by axial compression deformation and radial interference deformation at each contact hole. This ensures that each coaxially set first contact hole and second contact hole can maintain a very high coaxiality under various working conditions, which is beneficial for the insertion of pins in the adapter connector and the reset of the movable push rod when the head seat is separated.

[0032] In this embodiment, the socket contact assembly 6 includes a socket contact 61, an inner balancing bladder 62, a movable push rod 63, a conductive rod 64, and an elastic element 65. The inner balancing bladder 62 is fitted outside the socket contact 61, and the front end of the inner balancing bladder is inserted into the insertion hole 43 provided at the rear end of the insulating pressure plate 4, restricting the radial movement of the socket contact assembly. This insertion hole communicates with the corresponding second contact hole. The movable push rod 63 is slidably disposed inside the socket contact 61 in the front-back direction. The conductive rod 64 is connected to the rear end of the socket contact 61. The elastic element 65 is provided between the movable push rod 63 and the conductive rod 64. The elastic element 65 is used to provide a forward pushing force to the movable push rod so that the movable push rod closes the corresponding first and second contact holes when the connector is not inserted, preventing external liquid from entering the inner balancing bladder. The elastic element can be a spring, with its two ends respectively sleeved on the rear end post of the movable push rod and the front end post of the conductive rod. The outer wall of the movable push rod 63 is provided with a circumferentially extending flange 631. The flange 631 is used to axially stop and cooperate with the limiting platform 611 provided on the inner wall of the socket contact 61, so as to realize the reset limit of the movable push rod and prevent the movable push rod from dislodging forward from the socket contact. When the flange cooperates with the limiting platform, the outer peripheral surface of the movable push rod is sealed with the first contact hole and the second contact hole. The flange slides with the inner wall of the socket contact to guide the axial movement of the movable push rod. The gap 66 formed between the inner balance bladder 62 and the socket contact 61 is filled with pressure balancing fluid. The socket contact 61 has a slot to connect the gap 66 and the internal space 67 of the socket contact. The front end of the socket contact 61 is provided with an elastic inner sleeve 68. The elastic inner sleeve 68 is an elastic contact element. The elastic contact element is used to make elastic contact and conduct with the pin of the adapter connector. The elastic contact element can be a wire spring hole, crown spring, etc., to improve the contact stability between the pin and the socket contact. The front end of the socket contact 61 is further provided with an outer sleeve 69 that is fitted onto the elastic contact element. The outer sleeve 69 is used to radially support the inner balance bladder 62, maintain the shape of the front opening 621 of the inner balance bladder, and prevent the diameter of the front opening of the inner balance bladder from becoming too small, which would affect the insertion and removal of the connector or the reset of the movable push rod. The front opening and the movable push rod are in a sealed sliding fit. Furthermore, the flange 631 is provided with at least one axially through groove 6311. The through groove is used to connect the internal space 67 of the socket contact and the space where the elastic contact element is located. The space where the elastic contact element is located is the inner hole portion of the socket contact at the front end of its limiting platform 611, ensuring the flow of pressure balancing fluid in the inner balance bladder during the insertion process, so as to smoothly realize the connector insertion process.The conductive rod 64 and the socket contact 61 can be threaded together. After the conductive rod and the socket contact are threaded together, the rear end opening of the socket contact is sealed. The rear end of the inner balance bladder is interference-fitted with both the socket contact and the conductive rod to ensure a good seal and prevent leakage of the pressure balancing fluid in the inner balance bladder. In addition, a sealing ring 641 is provided between the conductive rod 64 and the socket insulator to further improve the sealing performance. The rear end of the conductive rod is provided with a terminal, which passes through the socket insulator and is used to connect wires.

[0033] The insulator provides forward support to the conductive rod, which in turn provides forward support to the socket contact. The socket contact, in turn, provides forward support to the inner balance bladder through the outer sleeve, thereby pressing the insulating pressure plate against the front end of the outer balance bladder.

[0034] At least one annular sealing protrusion 321 is provided on the inner wall of the first contact hole 32 of the outer balance bladder. When the present invention is inserted with the adapter connector, the annular sealing protrusion can scrape off external liquid carried on the pins of the adapter connector, preventing external liquid from entering the inner balance bladder during the connector insertion process. Similarly, annular sealing protrusions can also be provided on the inner wall of the front opening 621 of the inner balance bladder 62 and the movable push rod 63 in a sliding sealing fit.

[0035] Furthermore, the rear end of the outer balance bladder 3 is sealed and positioned with the front outer wall of the perforated insulator. Specifically, the rear end of the outer balance bladder 3 has a radially inwardly extending inwardly protruding sealing platform 35, and the outer outer wall of the front end of the perforated insulator 5 has a circumferentially extending sealing positioning groove 51. After the inwardly protruding sealing platform is engaged with the sealing positioning groove, an end face contact seal is formed, and the rear end of the outer balance bladder is squeezed and sealed between the outer shell and the perforated insulator. The outer balance bladder 3, the insulating pressure plate 4, and the perforated insulator 5 form a sealed cavity 8, in which the inner balance bladder is located. The sealed cavity is filled with pressure balancing fluid, and there is a deformation space 9 between the outer balance bladder and the outer shell for the outer balance bladder to expand when the connector is inserted. The pressure balancing fluid filled in the sealed cavity and the inner balance bladder can be silicone oil. When the connector is mated, the pins of the adapter connector push the movable push rod, the movable push rod retracts, the spring is compressed, and the pins enter the socket contact element and conduct through the elastic contact element, realizing the contact and conduction of the mating double-ended connector. At this time, the internal space of the inner balance bladder changes, and the inner balance bladder expands. The pressure is transmitted to the sealing cavity through the volume change of the inner balance bladder, and then the pressure is balanced by the deformation of the outer balance bladder. This facilitates the smooth underwater mating and unmating process of the connector and also reduces the sealing requirements of various sealing parts of the connector. In addition, the outer shell is provided with a drain hole 12 that connects the deformation space to the outside. External liquids can enter and exit the outer shell through the drain hole, further balancing the pressure changes in the sealing cavity during mating.

[0036] Since the movable push rod and the outer balance bladder achieve dynamic sealing through radial interference fit, in order to reduce the friction between the movable push rod and the outer balance bladder after the connector is inserted or removed, the material of the movable push rod is a PEEK material with self-lubricating function, which can reduce the friction coefficient between the movable push rod and the outer balance bladder, and facilitate the smooth rebound of the movable push rod after the connector is inserted and separated.

[0037] The above description is merely a preferred embodiment of the present invention, and all aspects not detailed herein are existing technologies. Any simple modifications, equivalent changes, and alterations made by those skilled in the art to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. An underwater pluggable connector, comprising a housing and an outer balancing bladder and a mounting hole insulator disposed within the housing, characterized in that: An insulating bushing is fitted on the outer wall of the front end of the outer balance bladder. An insulating pressure plate is provided inside the outer balance bladder. At least one insertion contact assembly is provided between the insulating pressure plate and the mounting insulator. The insertion contact assembly is used to press the insulating pressure plate axially forward against the front end face of the inner wall of the outer balance bladder. The insulating bushing is fixed in the outer shell and is used to axially position the outer balance bladder. A first contact hole is opened at the front end of the outer balance bladder. A second contact hole is provided on the insulating pressure plate corresponding to the first contact hole. A protrusion is provided at the front end of the insulating pressure plate near the second contact hole. A groove is provided on the front end face of the inner wall of the outer balance bladder to cooperate with the protrusion. The rear end of the insulating bushing has a limiting surface. The outer side of the front end of the outer balance bladder has a circumferentially extending stepped surface. The limiting surface and the stepped surface are axially stopped to restrict the forward movement of the outer balance bladder. The socket contact assembly includes a socket contact element, an inner balancing bladder, a movable push rod, and a conductive rod. The inner balancing bladder is fitted onto the outside of the socket contact element, and its front end is inserted into the insertion hole at the rear end of the insulating pressure plate. The movable push rod is slidably disposed within the socket contact element in the front-back direction. The conductive rod is connected to the rear end of the socket contact element. An elastic element is provided between the movable push rod and the conductive rod to provide a forward pushing force to the movable push rod, so that the movable push rod closes the corresponding first and second contact hole positions when the connector is not inserted. The outer balancing bladder, the insulating pressure plate, and the socket insulator form a sealed cavity filled with pressure balancing fluid. The inner balancing bladder is located in the sealed cavity, and there is a deformation space between the outer balancing bladder and the outer shell.

2. The underwater pluggable connector according to claim 1, characterized in that: The second contact hole has multiple protrusions, which are arranged in a ring array around the second contact hole.

3. The underwater pluggable connector according to claim 1, characterized in that: The rear end of the external balancing bladder is sealed to the front outer wall of the perforated insulator.

4. The underwater pluggable connector according to claim 1, characterized in that: The outer wall of the movable push rod is provided with a flange, which is used to axially stop the movable push rod from coming out of the socket contact member by engaging with the limiting platform provided on the inner wall of the socket contact member.

5. An underwater pluggable connector according to claim 1, characterized in that: The front end of the socket contact is provided with an elastic inner sleeve for elastic contact and conduction with the pins of the adapter connector. The front end of the socket contact is also provided with an outer sleeve fitted on the elastic inner sleeve. The outer sleeve is used to radially support the front opening of the inner balance bladder. The socket contact pushes the inner balance bladder forward through the outer sleeve so that the inner balance bladder contacts and engages with the insulating pressure plate.

6. An underwater pluggable connector according to claim 1, characterized in that: The conductive rod is threadedly connected to the socket contact to seal the rear end opening of the socket contact. The rear end of the inner balance bladder is sealed to the conductive rod. The rear end of the conductive rod has a terminal that extends backward through the socket insulator.

7. An underwater pluggable connector according to claim 1, characterized in that: At least one annular sealing protrusion is provided on the inner wall of the first contact hole, and at least one annular sealing protrusion is also provided on the inner wall of the front opening of the inner balance bladder and the movable push rod sliding sealing cooperation.

8. An underwater pluggable connector according to claim 1, characterized in that: A retaining ring is embedded in the inner wall of the front end of the outer casing. The retaining ring is axially stopped by the insulating bushing to restrict the forward movement of the insulating bushing.

9. An underwater pluggable connector according to any one of claims 1 to 8, characterized in that: The movable push rod is made of PEEK material with self-lubricating properties.

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